[PATCH v34 0/7] firmware: imx: driver for NXP secure-enclave

[PATCH v34 0/7] firmware: imx: driver for NXP secure-enclave

[pankaj.gupta]

The NXP's i.MX EdgeLock Enclave, a HW IP creating an embedded secure
enclave within the SoC boundary to enable features like
- HSM
- SHE
- V2X

Communicates via message unit with linux kernel. This driver is
enables communication ensuring well defined message sequence protocol
between Application Core and enclave's firmware.

Driver configures multiple misc-device on the MU, for multiple
user-space applications can communicate on single MU.

It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.

-------
Changes in v34:
5/7:
Teardown vs. in-flight transaction (lost wakeup / unbind hang):
- se_if_probe_cleanup() now sets priv->going_away under clbk_rx_lock
  instead of se_if_cmd_lock. se_if_cmd_lock is held across the whole
  blocking transaction, so acquiring it during unbind could stall for a
  full receive timeout. clbk_rx_lock is the short spinlock the sender
  holds while arming a transaction, so setting going_away under it and
  then calling complete_all() makes teardown and arming mutually
  exclusive and closes the lost-wakeup window.
- complete_all() is issued before walking the device-context list so a
  waiter sleeping on the completion while holding dev_ctx->fops_lock is
  released before cleanup takes the same lock, avoiding an unbind hang.

ele_msg_send_rcv() arming:
- going_away and fw_busy are now evaluated under clbk_rx_lock together
  with reinit_completion() and the buffer publish, so a new transaction
  is never armed concurrently with teardown.
- going_away is checked before fw_busy so a caller racing unbind gets a
  permanent -ENODEV rather than a misleading retryable -EBUSY. fw_busy
  is only atomic_read() here, so no fw_busy_lock is taken and there is
  no deadlock. Teardown session/storage close commands issued on
  priv_dev_ctx are still let through so the kernel can resynchronise
  state with FW.

ele_msg_rcv() response classification:
- Add se_clbk_handle::rx_delivered, set by se_if_rx_callback() under
  clbk_rx_lock only after a real response is copied. ele_msg_rcv() uses
  it to tell a genuine firmware response apart from a teardown-forced
  complete_all() that wakes the waiter with no data. Without this a
  teardown-time close response could be mistaken for the forced abort,
  failing the close and leaking its DMA buffer, and a forced wakeup
  could be mistaken for a response while the enclave still DMAs into the
  shared buffer. The forced-abort path returns -ENODEV and arms the
  circuit breaker so the buffer is quarantined, not freed.

Session/storage handle tracking (ele_uapi_allowed_fw_cmd()):
- Reject a repeated ELE_SESSION_OPEN_REQ / ELE_STORAGE_OPEN_REQ with
  -EEXIST when a handle is already open, preventing a handle leak.
- Reject ELE_SESSION_CLOSE_REQ / ELE_STORAGE_CLOSE_REQ with -ENXIO when
  no handle is open.

se_close_session() / se_close_storage():
- Use __free(kfree) scope-based cleanup consistently and return directly
  instead of mixing it with goto-based cleanup.

Reference:
- Link to v33: https://lore.kernel.org/r/20260805-imx-se-if-v33-0-212e32ff0295@nxp.com

Changes in v33:
5/7: Sashiko AI comment disposition (5/7, 8 comments; 5 fixed, 3 no-change):

- [High] 32/64-bit ABI mismatch in struct se_ioctl_cmd_snd_rcv_rsp_info:
  FIXED. The members were ordered __u64 tx_buf, __u32 tx_buf_sz, __u64
  rx_buf, __u32 rx_buf_sz, so the second __u64 (rx_buf) forced 4 bytes of
  implicit padding after tx_buf_sz. That padding makes the struct size
  (and therefore the _IOWR() size baked into SE_IOCTL_CMD_SEND_RCV_RSP)
  differ between 32- and 64-bit userspace. The two __u64 members are now
  placed first, followed by the two __u32 members, giving a naturally
  packed, padding-free layout that is identical for 32- and 64-bit
  callers.
- [High] fops write/read/ioctl/open returned -EBUSY when the interruptible
  mutex acquisition was aborted by a signal: FIXED. scoped_cond_guard(
  mutex_intr, ...) and mutex_lock_interruptible() abort with an
  interrupted-wait status when a signal is pending, but the handlers
  anslated that into -EBUSY, which userspace cannot distinguish from a
  genuinely contended device and which defeats automatic syscall restart.
  The interrupted-acquire paths in se_if_fops_write(), se_if_fops_read(),
  se_if_fops_open() (both the gate->lock and priv_dev_ctx->fops_lock
  acquisitions) and se_ioctl() now return -ERESTARTSYS, so the kernel
  restarts the syscall or reports -EINTR per the caller's SA_RESTART
  disposition. The three remaining -EBUSY returns (command receiver
  already registered, and the two firmware-busy circuit-breaker checks)
  are genuine non-signal conditions and are intentionally left unchanged.

- [High] se_if_fops_read() could strand an already-consumed response when
  the fops_lock reacquire after the wait was interrupted: FIXED. The read
  path drops fops_lock while waiting for the firmware response and then
  reacquired it with mutex_lock_interruptible(), returning -ERESTARTSYS on
  a pending signal. By that point the message had already been received
  and committed, so aborting on a signal discarded a completed response
  that could not be re-fetched. The reacquire now uses an uninterruptible
  mutex_lock(); the wait itself stays interruptible, and the cleanup_done
  re-check under fops_lock is preserved.

- [High] TOCTOU / lost-wakeup between ele_msg_send_rcv() and
  se_if_probe_cleanup(): FIXED. ele_msg_send_rcv() checks going_away and
  arms the response completion under se_if_cmd_lock, but teardown set
  going_away and called complete_all() outside that lock. A thread parked
  on se_if_cmd_lock could therefore arm the completion after the teardown
  wakeup had already fired, then block for the full timeout while unbind
  waited on that thread's fops_lock. se_if_probe_cleanup() now sets
  going_away and calls complete_all() while holding se_if_cmd_lock, making
  teardown and the arming path mutually exclusive so the wakeup can no
  longer be lost. As part of tear-down, close-session & close-storage msg
  is sent to FW using priv_dev_ctx, to keep FW in sync.

- [High] NULL-pointer dereference on the init_misc_device_context() error
  path: FIXED. dev_ctx->priv was assigned only after the kasprintf() that
  builds devname, but the kasprintf() failure path jumps to a cleanup that
  calls cleanup_se_shared_mem(), which dereferences dev_ctx->priv->mem_pool.
  If kasprintf() failed, priv was still NULL and cleanup dereferenced NULL.
  The dev_ctx->priv = priv assignment is moved to immediately after the
  allocation succeeds, before any goto to the error path.

- [High] Unbounded per-open DMA allocation (device-context exhaustion):
  NO-CHANGE. Each open() reserves a MAX_DATA_SIZE_PER_USER (128 KB) buffer
  via dma_alloc_coherent(), but on these platforms the device is bound to
  a fixed no-map reserved DMA pool (the ele_reserved "shared-dma-pool"
  region attached with of_reserved_mem_device_init() in probe).
  Allocations are served exclusively from that bounded pool and cannot
  exhaust general system memory; once the pool is full dma_alloc_coherent()
  returns NULL, init_se_shared_mem() returns -ENOMEM and open() fails
  gracefully. The bounded pool together with the per-process RLIMIT_NOFILE
  is the real, self-adjusting limit, so no artificial open-count cap is
  added. No code change.

- [High] SE_IOCTL_CMD_SEND_RCV_RSP reports -EINTR for a successful but
  signal-interrupted transaction: NO-CHANGE. This is the intended Ctrl+C
  behaviour. The underlying firmware command is not idempotent and must
  not be silently re-issued, so once the wait is interrupted the
  deferred-signal path resynchronises the protocol and ele_msg_send_rcv()
  reports -ERESTARTSYS, which the handler surfaces as -EINTR to the
  interrupted application. Reporting plain success here would hide the
  interruption from the caller. No code change.

- [High] Use-after-free of the open gate / priv between open() and unbind:
  NO-CHANGE (false positive). misc_open() and misc_deregister() are
  serialised by misc_mtx, and the open path takes a reference on the stable
  se_if_open_gate with kref_get_unless_zero() and re-validates
  gate->dying / gate->priv under gate->lock before use, so it can never
  operate on a torn-down gate. No code change.

3/7
- Sample jiffies once. jiffies is volatile, so reading
  it separately for the deadline check and for the
  remaining-time subtraction would be a TOCTOU: a timer
  tick (or a NO_HZ/virtualized tick catch-up that jumps
  jiffies by several ticks) landing between the two
  reads could push jiffies past the deadline and make
  deadline_jiffies - jiffies underflow to a near
  ULONG_MAX timeout, hanging the wait. One snapshot
  keeps both uses consistent, so now < deadline_jiffies
  guarantees a strictly positive remainder.

Reference:
- Link to v32: https://lore.kernel.org/r/20260730-imx-se-if-v32-0-95f56dff4ba9@nxp.com

Changes in v32:
5/7:
- [Critical, new] Kernel panic while traversing the uninitialised
  mem_pool_buf_list head during device-context cleanup: FIXED.
  init_se_shared_mem() only ran INIT_LIST_HEAD() on mem_pool_buf_list
  when priv->mem_pool was non-NULL, but cleanup_se_shared_mem() called
  se_cleanup_mem_pool_buf() unconditionally, and that walks the head
  with list_for_each_entry_safe() on every close/teardown. On interfaces
  with no gen_pool (e.g. imx93, which has no pool_name so
  priv->mem_pool == NULL) the head stayed zero-filled (next/prev == NULL)
  and the cleanup walk dereferenced NULL. cleanup_se_shared_mem() now
  calls se_cleanup_mem_pool_buf() only when priv->mem_pool is non-NULL;
  interfaces without a pool have nothing to reclaim, so the walk is
  simply skipped.
- [High, new] SE_IOCTL_CMD_SEND_RCV_RSP returned a positive value to
  userspace on success, masking the plain-success contract: FIXED.
  ele_msg_send_rcv() returns a positive received-message size on success,
  so on the happy path err held that size and was returned as the ioctl
  result, making a successful transaction look like a positive (non-zero)
  return value. The handler now records the received size in
  rx_buf_sz (copied back to userspace in the response info) and
  normalises err to 0 so the ioctl reports plain success. The firmware
  response header/status is validated by se_val_rsp_hdr_n_status() and
  conveyed to userspace inside the response buffer itself; an -EFAULT
  copy_to_user() failure or a cleanup error still takes precedence over
  the success return.
- [High, new] slab-out-of-bounds read in se_val_rsp_hdr_n_status() when
  handling debug-dump responses with a small rx_buf_sz: FIXED. Commands
  that take the variable-length exception in check_hdr_exception_for_sz()
  bypass the header/size match check, so the caller's receive buffer may
  be smaller than the size the firmware header claims. Reading the status
  word msg->data[0] with an rx_buf_sz as small as SE_MU_HDR_SZ over-read
  the allocation. The status word is now read only when both the firmware
  header count (header->size) and the received size in words (sz >> 2)
  exceed the header word SE_MU_HDR_WORD_SZ, so a debug-dump response whose
  received buffer is too small to hold the status word skips the read
  instead of over-reading the allocation.
- [High, pre-existing] Internal kernel HW ops (IMEM save/restore during
  suspend/resume) fail spuriously with -ERESTARTSYS when a signal is
  pending, breaking PM transitions: FIXED. All internal kernel-initiated
  transactions run on priv->priv_dev_ctx (probe-time get_info/ping,
  firmware authentication, and the PM IMEM export/import). These are not
  issued on behalf of a restartable userspace syscall, so ele_msg_rcv()
  now waits uninterruptibly whenever dev_ctx == priv->priv_dev_ctx. The
  freezer's fake signals raised during a system PM transition can no
  longer abort them with -ERESTARTSYS; only genuine userspace ioctl/read
  waiters remain interruptible and use the existing deferred-signal path.
- [Critical, new] Userspace can construct raw command payloads and embed
  unvalidated DMA addresses (confused-deputy): NO-CHANGE. Passing
  physical/DMA addresses inside the message body is inherent to the
  firmware ABI this interface exposes, and is constrained by
  se_chk_tx_msg_hdr() -> ele_uapi_allowed_base_cmd()/
  ele_uapi_allowed_fw_cmd(), which restrict the command set to a
  vetted allow-list (power-management, reset, BBSM, RNG init, FW
  re-init, CAAM resource release and SE internal memory management are
  all blocked). The enclave firmware is the trust boundary that
  validates addresses against the caller's provisioned resources;
  per-command address bounds-checking in the kernel would duplicate that
  policy without owning the authoritative resource map. No code change.
- [High, new] Firmware commands to the command receiver can overwrite an
  unprocessed command (se_if_rx_callback() cmd_tag branch memcpy+complete
  unconditionally): NO-CHANGE. The NVM command-receiver protocol is
  half-duplex: the firmware issues one storage/NVM command at a time and
  waits for the userspace daemon's response before issuing the next, so
  there is no in-flight command to overwrite. The receiver uses a
  dedicated long-lived buffer and clbk_rx_lock already serialises the
  callback against se_if_fops_read(). No code change.
- [High, new] TOCTOU race between ele_msg_send_rcv() checking going_away
  and se_if_probe_cleanup() forcing wakeup (lost wakeup / deadlock):
  NO-CHANGE. The ordering is already safe: se_if_probe_cleanup() sets
  going_away before complete_all() (with an explicit ordering comment),
  ele_msg_send_rcv() reads going_away under se_if_cmd_lock and bails with
  -ENODEV before reinit_completion(), and ele_msg_rcv() re-checks
  going_away after the wake and returns -ENODEV so a teardown-forced
  completion is never mistaken for a real response. No code change.

4/7:
- moved the cleanup of priv_dev_ctx->dev_name & priv_dev_ctx, in the end of
  se_if_probe_cleanup(), after priv->rx_chan freed.
  Though it gets replaced in the next patch.

Reference:
- Link to v31: https://lore.kernel.org/r/20260729-imx-se-if-v31-0-e59af7adb784@nxp.com

Changes in v31:
7/7
- Kernel is free to choose the exact placement of the 1 MiB block, as long
  as it lands inside the ELE-accessible window. This avoids hardcoding a
  fixed address.
- Adds a new shared imx8ulp-firmware.dtsi that also enables the hsm0
  node and wires up its memory-region, so every i.MX8ULP board can bring up
  the enclave with a single include instead of duplicating the reserved
  memory node. Include it from imx8ulp-evk.

6/7:
- Keep the node disabled in the SoC dtsi so it does not impose a
  reserved-memory requirement on every board. Boards enable the enclave and
  provide its memory-region by including imx8ulp-firmware.dtsi.

5/7:
- [Critical, new] Driver unbind forcefully wakes waiting ioctls and
  clears firmware-busy state, causing DMA use-after-free by hardware:
  FIXED. ele_msg_rcv() detects the teardown-forced wake
  (is_rsp_wait_with_timeout && going_away), clears rx_msg, arms the
  circuit breaker via se_mark_fw_busy() and returns -ENODEV; the woken
  thread no longer treats the forced wake as success and does not free
  the buffer. se_clear_fw_busy() quarantines (does not reclaim) the DMA
  buffer during teardown.
- [High, new] Late mailbox interrupt schedules fw_busy_work after
  cancel_work_sync(), use-after-free of priv: FIXED.
  se_if_probe_cleanup() now frees the rx mailbox channel
  (mbox_free_channel) before cancel_work_sync(&priv->fw_busy_work), so
  no further se_if_rx_callback() can re-arm the work; the cancel is
  final.
- [High, new] Unbind deadlock/hang: a concurrent ioctl blocked on
  se_if_cmd_lock misses complete_all(), re-arms and waits the full
  timeout while unbind blocks on fops_lock: FIXED. going_away is set at
  the very start of teardown before complete_all(); ele_msg_send_rcv()
  checks going_away under se_if_cmd_lock and returns -ENODEV before
  reinit_completion(), so the thread bails out instead of re-arming.
= [Medium, new] 128 KB DMA shared-memory buffer of the internal
  priv_dev_ctx permanently leaked on unbind: FIXED. New
  se_shared_mem_mgmt_info.mem_pool_buf_list plus
  se_get_mem_pool_buf()/se_cleanup_mem_pool_buf() track pool
  allocations; se_if_priv_release() reclaims the internal context
  directly so the buffer is released deterministically (except the
  intentional fw_busy quarantine from the Critical fix above).
- [High, pre-existing] Race between se_if_rx_callback() and
  se_if_fops_read() on the shared rx_msg command-receiver buffer, data
  corruption: FIXED. se_if_fops_read() bounces the payload into a local
  u8 rx_msg_snap[MAX_NVM_MSG_LEN] under clbk_rx_lock, then
  copy_to_user() from the private copy after unlocking. copy_len is
  bounded by MAX_NVM_MSG_LEN so the stack buffer cannot overflow.
- [High, pre-existing] Dangling priv->dev passed to
  dma_free_coherent()/dev_warn() if an fd is closed after device unbind:
  FIXED. get_device(priv->dev) in se_if_probe() pins the parent device
  for the lifetime of priv and is balanced by put_device(priv->dev) in
  se_if_priv_release(), so priv->dev stays valid for a late close().

4/7:
-  add the cleanup of priv_dev_ctx->dev_name & priv_dev_ctx, as part of
   se_if_probe_cleanup(). Though it gets replaced in the next patch.

3/7:
- ele_msg_send_rcv(): publish rx_msg/rx_msg_sz under clbk_rx_lock so
  se_if_rx_callback() cannot observe a torn pair. This change is part
  of 5/7, already.
- ele_msg_rcv(): engage the fw_busy breaker on the deadline path, like
  the ret==0 path, so a hung FW is fenced.
- ele_get_info(): zero the gen_pool_dma_alloc() buffer, which is not
  zeroed on allocation.

Two findings need no code change:
- DMA free on timeout: -ETIMEDOUT means FW is fenced by fw_busy, so the
  free is safe.
- -ERESTARTSYS after a completed transaction: the command is not
  re-sent and the ioctl path converts it to -EINTR.

References:
- Link to v30: https://lore.kernel.org/r/20260724-imx-se-if-v30-0-ce8ba256692c@nxp.com

Changes in v30:

3/7
This change dispositions all six findings from the Sashiko AI review:
- Five are code fixes (three in se_ctrl.c, two in ele_common.c);
- One is documented as intentional protocol-synchronization behavior.

Addressed (drivers/firmware/imx/se_ctrl.c):
- [High] Incorrect devres registration order (UAF / NULL pointer deref
  in the mailbox RX callback):
- [Medium] priv structure leak on early probe failure paths:
  The cleanup action is now registered before the channel requests, so
  priv is released even if se_if_request_channel() fails early.
- [Medium] soc_device singleton lifecycle tied to the first probed MU
  interface (data race and premature sysfs deletion):
  Decouple the singleton from the first-probed MU interface. Track it in
  var_se_info.soc_dev_regn and release it once at module unload via an
  explicit module_init()/module_exit() pair instead of a devm action on
  priv->dev. Serialize soc_dev registration state under se_var_info_lock;
  se_soc_device_unregister() now takes the lock via guard(mutex).

Addressed (drivers/firmware/imx/ele_common.c):
- [High] Data race on rx_msg_sz in se_if_rx_callback():
  Move the read of the expected response size (exp_rx_msg_sz =
  se_clbk_hdl->rx_msg_sz) to after clbk_rx_lock is acquired, so it can no
  longer be observed stale relative to a concurrent transaction updating
  rx_msg_sz under the lock. This prevents copying truncated or corrupted
  response data.
- [Medium] ele_msg_rcv() reset the timeout after a signal instead of
  accounting for elapsed time:
  For the response-waiter path, compute an absolute deadline_jiffies once
  and derive remaining_jiffies from it on every iteration. After a signal
  falls back to an uninterruptible wait, the wait no longer restarts the
  full timeout; the deadline is honored and -ETIMEDOUT is returned when it
  elapses.

Documented as intentional, no code change (drivers/firmware/imx/ele_common.c):
- [Medium] "Unsafe syscall restart on completed non-idempotent hardware
  operations" in ele_msg_send_rcv():
  This is intentional protocol-synchronization behavior, not a
  re-execution bug. A signal is deliberately not acted on while a firmware
  message exchange is in progress; ele_msg_rcv() defers it until the
  response path completes and the FW/kernel protocol state is synchronized
  again, so Linux and firmware never diverge on message ownership. Only
  after synchronization is the interrupted wait surfaced to userspace via
  -ERESTARTSYS. The command/response ABI must treat this as an interrupted
  operation after synchronization; it is not permission for the kernel
  driver to re-send the command, so the enclave never receives it twice.
  Clarified with an expanded code comment.

4/7: Sashiko AI issues resolved in this patch; no functional change
     required beyond a cosmetic whitespace cleanup:

- [High][NEW] Accessing se_clbk_hdl->dev_ctx->devname outside
  clbk_rx_lock in the cmd_tag path (UAF / NULL deref):
  Already fixed. In se_if_rx_callback(), the cmd_tag path holds
  clbk_rx_lock across the dev_dbg() that reads dev_ctx->devname and only
  proceeds after the explicit "!se_clbk_hdl->dev_ctx" check. The devname
  used by the post-unlock dev_err() is cached into a local (devname)
  while the lock is still held, so no dev_ctx dereference happens outside
  the lock.
- [High] Incorrect devm registration order frees priv while the RX
  mailbox channel is still active (NULL deref):
  Already fixed in drivers/firmware/imx/se_ctrl.c. se_if_probe()
  registers devm_add_action_or_reset(dev, se_if_probe_cleanup, pdev)
  before requesting the tx/rx mailbox channels, so LIFO teardown frees
  the channels (se_if_probe_cleanup) before priv is released.
- [High] Memory leak of priv when early probe steps fail:
  Already fixed by the same change. priv is allocated, stored via
  dev_set_drvdata(), and its release is tied to se_if_probe_cleanup(),
  which is registered early; any subsequent probe failure unwinds through
  the devres action that frees priv.
- [High] Unprotected read of rx_msg_sz creates a TOCTOU race leading to
  response truncation on late interrupts:
  Already fixed. The rsp_tag path in se_if_rx_callback() reads
  exp_rx_msg_sz = se_clbk_hdl->rx_msg_sz only after acquiring
  clbk_rx_lock (and after confirming rx_msg != NULL), so the size cannot
  change between the check and the memcpy().

5/7:
[High] Overwriting a successful firmware transaction with -ERESTARTSYS
  leads to double execution with zeroed DMA buffers.
  Fixed. se_ioctl_cmd_snd_rcv_rsp_handler() now converts the deferred
  -ERESTARTSYS returned by ele_msg_send_rcv() into -EINTR before returning
  to userspace. -EINTR is not auto-restarted by the VFS, so the ioctl is
  not silently re-run against the already cleaned-up (zeroed) shared input
  buffers. Userspace decides whether to reissue the command.

[High] Unbind deadlock/hang caused by incorrect ordering of complete_all()
  and fops_lock.
  Fixed. In se_if_probe_cleanup(), complete_all() on the response waiter is
  now issued before the dev_ctx_list cleanup loop. The blocked ioctl waiter
  sleeps in ele_msg_rcv() while holding its dev_ctx->fops_lock, and
  cleanup_dev_ctx() takes the same lock; waking the waiter first lets it
  drop fops_lock so teardown can proceed instead of hanging.

[High] NULL pointer dereference in se_if_rx_callback().
  Fixed in 3/7. se_if_rx_callback() now checks priv (dev_get_drvdata()) for
  NULL before use. A late mailbox interrupt can be delivered during tear-
  down; the callback returns early instead of dereferencing a cleared
  drvdata.

[High] Out-of-bounds read/write in se_if_rx_callback() by trusting the
  unvalidated firmware payload length.
  Fixed in 3/7. Both the cmd_tag and rsp_tag paths now clamp the memcpy()
  length to min(firmware-declared size, destination buffer capacity). The
  copy never trusts the firmware size beyond what fits in either buffer; a
  size mismatch is still reported after the lock is dropped.

[High] Premature freeing of the gen_pool DMA buffer on timeout.
  Fixed. ele_get_info_cleanup() now guards the gen_pool_free() path with
  se_is_fw_busy_ctx(), mirroring the existing guard on the shared-memory
  path. If the probe-time transaction timed out and firmware may still
  write the SRAM buffer, the buffer is not returned to the pool (it is
  reclaimed with the device on unbind) to avoid pool corruption.

[Medium] Lockdep false positive "possible recursive locking detected" on
  fops_lock.
  Fixed. The internal priv_dev_ctx fops_lock is given a distinct lockdep
  class via lockdep_set_class(). Taking it while an open context's
  fops_lock is held (e.g. a firmware load triggered from an ioctl) is
  valid hierarchical locking and is no longer misreported.

[Medium] Early device exposure to userspace before probe completes.
  Fixed. misc_register() is deferred out of init_misc_device_context() into
  se_if_misc_register(), called at the very end of se_if_probe() after SoC
  info is fetched and the encrypted-IMEM buffer is allocated. The dev_ctx
  and its shared memory are still set up early because the internal
  probe-time ELE_GET_INFO transaction uses priv->priv_dev_ctx directly. A
  new se_if_open_gate.registered flag ensures se_if_probe_cleanup() only
  calls misc_deregister() when registration actually succeeded.

[Critical] Arbitrary physical memory read/write (Confused Deputy) via
  SE_IOCTL_CMD_SEND_RCV_RSP.
  By design, no code change. The SE messaging-unit protocol legitimately
  carries firmware-owned physical DMA addresses inside command payloads, so
  the kernel cannot treat those addresses as the trust boundary. The node is
  root-only (0600); the ELE firmware and the SoC memory-domain/xRDC hardware
  enforce which physical regions the enclave may access, and
  se_chk_tx_msg_hdr() already restricts the permitted command set (power,
  reset, BBSM, FW re-init, RNG init, CAAM release and SE internal memory
  management are all blocked from user-space).

[High] Use-After-Free of gate and miscdev due to a race between unbind and
  VFS open.
  Already safe, documented as defense-in-depth; no code change. misc_open()
  invokes file->f_op->open() while holding misc_mtx, and misc_deregister()
  acquires the same misc_mtx before removing the node, so open() is fully
  serialized against deregistration. The gate is additionally kref-counted
  and se_if_fops_open() takes its reference via kref_get_unless_zero(), so a
  VFS-resolved but not-yet-run open() can never observe a freed gate or
  miscdev.

[Low] Implicit compiler padding in UAPI struct se_ioctl_cmd_snd_rcv_rsp_info.
  WONTFIX, no code change. include/uapi/linux/se_ioctl.h is a stable ABI that
  has shipped to NXP customers for around two years; the member order cannot
  be changed without breaking existing user-space. The 4-byte hole after
  tx_buf_sz is part of the established, frozen layout. The struct uses only
  fixed-width __u64/__u32 members, and the ARM AAPCS aligns 64-bit types to
  8 bytes on both the 32-bit (AArch32) and 64-bit (AArch64) ABIs this i.MX
  driver targets, so the layout (members at offsets 0/8/16/24, sizeof 32) is
  identical for 32-bit and 64-bit user-space and needs no compat-ioctl
  translation.

Reference:
- Link to v29: https://lore.kernel.org/r/20260721-imx-se-if-v29-0-04a362f4fcca@nxp.com

Changes in v29:
5/7:
- Fix ele_get_info() mem_pool path by initializing get_info_len before
  gen_pool_dma_alloc() and checking allocation failure before using the
  returned buffer.

- Add a probe-time comment for ELE_GET_INFO timeout cleanup. The SRAM buffer is
  used only during probe, and a timeout means the secure-enclave interface is
  considered unsynchronized and probe fails.

- Serialize internal priv_dev_ctx shared-memory allocation by taking
  priv_dev_ctx->fops_lock in ele_get_info() and load_firmware().

- Move load_firmware() to use priv_dev_ctx shared memory instead of a temporary
  dma_alloc_coherent() buffer, and skip shared-memory cleanup while priv_dev_ctx
  is marked fw_busy.

- Fix init_misc_device_context() error handling so gate allocation failure sets
  ret = -ENOMEM and releases previously allocated shared memory before freeing
  the device context.

- Release priv_dev_ctx resources through cleanup_dev_ctx() before freeing
  priv_dev_ctx during priv release.

- Guard cleanup_se_shared_mem() against being called before coherent shared
  memory was allocated.

- Fix se_if_fops_read() initialization by assigning priv before first use.

- Avoid modifying command-receiver rx_msg_sz when read() is called from a
  non-command-receiver context.

- Rework se_if_fops_read() to reacquire fops_lock after ele_msg_rcv() returns
  before accessing shared-memory lists or command-receiver state.

- Snapshot the command-receiver rx_msg under clbk_rx_lock and hold modify_lock
  while copying it to userspace, preventing concurrent command-receiver teardown
  from freeing the buffer.

- Clear command-receiver rx_msg_sz under clbk_rx_lock only after consuming the
  message.

- Keep shared-memory cleanup in the read path under fops_lock.

- Mark priv_dev_ctx cleanup_done under fops_lock during probe cleanup so open()

- Register se_if_probe_cleanup after mailbox channel requests so devres LIFO
  ordering runs misc-device cleanup before mailbox channel release.

- Initialize firmware-load state before exposing the misc device to userspace.

4/7:
- priv->waiting_rsp_clbk_hdl.dev_ctx, priv->waiting_rsp_clbk_hdl.rx_msg,
  priv->waiting_rsp_clbk_hdl.rx_msg_sz will be updated after
  acquiring the clbk_rx_lock.
- Create a local variable "const char *devname" and assigned its value
   under the clbk_rx_lock in se_if_rx_callback().

3/7:
- Remove file descriptor, shared-memory setup, and userspace send/receive
  working from the initial Kconfig help text, because the misc-device UAPIs
  added later in the series.

- Replace unaligned u32 pointer access in GET_SERIAL_NUM_FROM_UID() with
  get_unaligned_le32(), avoiding undefined behavior when parsing UID data
  from byte-aligned buffers.

- Add SE_RCV_MSG_DEFAULT_TIMEOUT_MS and set the default response timeout to
  3000 ms.

- Replace MAX_SCHEDULE_TIMEOUT in ele_msg_rcv() with a bounded default response
  timeout using SE_RCV_MS_DEFAULT_TIMEOUT_MS.

- Start handling mailbox messages with IS_ERR_OR_NULL() in se_if_rx_callback()
  before dereferencing msg.

- Fix SoC revision string formatting to print major.minor instead of
  mijor.major.

Fixes for issues reported by Sashiko AI bot on 5/7:
- Move se_if_probe_cleanup devres registration right after mailbox channel
  requests.

- Split the changes into two so that:
  - Initialize load_fw_lock and firmware-load state before the misc device can be
    registered or exposed to userspace in 5/7. Setting load_fw->se_fw_img_nm and
    load_fw->is_fw_tobe_loaded before possible userspace access to the misc device.

  - Keep IMEM management independent from runtime firmware loading metadata.
    Add imem_state_mgmt to struct se_soc_info to separate IMEM save/restore
    buffer management from firmware image availability. Enable IMEM state
    management explicitly for i.MX8ULP by setting imem_state_mgmt = true.
    Allocate encrypted IMEM buffer based on imem_state_mgmt instead of tying it
    to prim_fw_nm_in_rfs.

Reference:
- Link to v28: https://lore.kernel.org/r/20260717-imx-se-if-v28-0-0a9659c7e69d@nxp.com

Changes in v28:

5/7: Fix 10 of the 13 issues reported by Sashiko AI review

- [High] se_ctrl.c: se_if_fops_read(): reacquire fops_lock after
ele_msg_rcv() returns before accessing pending lists or rx_msg.
fops_lock is dropped before the blocking wait; a concurrent close could
free the DMA buffers and pending lists while the read is blocked, leading
to UAF and list corruption. Re-check cleanup_done under fops_lock before
touching any shared state.

- [High] ele_common.c: se_val_rsp_hdr_n_status(): guard msg->data[0] read
with if (header->size > SE_MU_HDR_WORD_SZ). A header-only response (1
word) is valid; the unconditional read caused a KASAN slab-out-of-bounds.

- [High] ele_common.h: reduce SE_RCV_MSG_DEFAULT_TIMEOUT from 5000 s to
3000 ms. After a signal interrupts the interruptible wait, ele_msg_rcv()
switches to TASK_UNINTERRUPTIBLE. A 5000-second uninterruptible sleep
reliably triggers the hung-task watchdog. 3000 ms is well below the
default 120 s threshold.

- [High] se_ctrl.c: cleanup_se_shared_mem(): call
se_dev_ctx_shared_mem_cleanup() to free se_buf_desc list entries before
releasing the DMA backing memory, fixing a leak when the fd is closed
with pending I/O buffers.

- [High] se_ctrl.c: se_dev_ctx_shared_mem_cleanup(): skip memset of DMA
buffers when the context is the fw_busy one (command timed out). The
firmware may still be actively accessing the buffer; zeroing it would
corrupt the in-flight DMA transaction.

- [High] se_ctrl.c: cleanup_se_shared_mem(): guard against calling
dma_free_coherent() with a NULL ptr (probe failure before DMA alloc
succeeded).

- [High] The command-receiver rx_msg_sz update is now done under
cmd_receiver_clbk_hdl.clbk_rx_lock. The read path also validates
cmd_receiver_clbk_hdl.dev_ctx, rx_msg, and rx_msg_sz under the same callback
lock before consuming the message.

- [High] se_ctrl.c: se_if_probe_cleanup(): call se_clear_fw_busy() before
cancel_work_sync(). A late mailbox interrupt arriving between the two
calls would see fw_busy still set and schedule work on the already-
cancelled fw_busy_work, causing a use-after-free.

- [Medium] se_ctrl.c: cleanup_dev_ctx(): remove goto from inside a
scoped_guard() block. Use a local already_done flag instead to keep the
cleanup path flat and avoid confusing ownership semantics.

- [Misc] se_ctrl.c: se_ctrl.h: add SE_MU_HDR_WORD_SZ = 1 constant.
Make se_is_fw_busy_ctx(), se_dev_ctx_shared_mem_cleanup() and
get_shared_mem_slot() non-static so they can be called from ele_common.c
and future callers.

4/7: Fix init_misc_device_context() to return 0 on the success path.

- The helper initialized ret to -ENOMEM and returned ret even after
successfully allocating and initializing priv_dev_ctx. This caused
se_if_probe() to treat a successful init_misc_device_context() call as a
failure and abort probe. Return 0 after assigning *new_dev_ctx.

- Avoid a possible NULL pointer dereference in se_if_rx_callback() after
waking the synchronous response waiter. The response callback used
se_clbk_hdl->dev_ctx->devname after calling complete() and dropping
clbk_rx_lock. The awakened ele_msg_send_rcv() cleanup path can clear
waiting_rsp_clbk_hdl.dev_ctx under the same lock before the size-mismatch
dev_err() is emitted. Snapshot devname while clbk_rx_lock is still held and
use the local copy after dropping the lock.

3/7: Fix several issues reported by Sashiko in the ELE driver:

- Add cleanup helper for ele_get_info() and remove the goto-based cleanup path
  that mixed manual cleanup with scoped __free(kfree) objects.

- Document the mailbox TX buffer lifetime assumption in ele_msg_send().
  The i.MX MU mailbox controller copies message payload words into MU
  registers synchronously and does not retain the caller-provided tx_msg
  pointer after mbox_send_message() returns.

- Replace se_get_msg_chksum() with se_update_msg_chksum(), which validates
  the message pointer and size, calculates the checksum, and updates the
  checksum word directly.

- Remove the stale ret check after se_fill_cmd_msg_hdr(), since
  se_fill_cmd_msg_hdr() now returns void.

- Validate the encrypted IMEM export size returned by firmware against
  ELE_IMEM_SIZE before storing it in imem->size for later resume-time import.

- Add a mutex to serialize population of common SoC-level information stored
  in var_se_info.

- Add NULL checks for devm_kasprintf() results before passing revision and
  serial-number strings to soc_device_register().

- Set a 32-bit DMA/coherent mask to make the ELE 32-bit firmware address
  constraint explicit, while still relying on the reserved memory region for
  ELE-accessible DMA memory.

- Keep mutable firmware-load and IMEM state per device in struct se_if_priv,
  while var_se_info only caches immutable SoC-level revision data.

- Keep the SoC device unregister devres action and devm-managed IMEM coherent
  memory handling from v27.

Reference:
- Link to v27: https://lore.kernel.org/r/20260715-imx-se-if-v27-0-bb7c45952f06@nxp.com

Changes in v27:

Address Sashiko findings around:
Changes in v27:

Address Sashiko findings around:
- Encrypted IMEM DMA address handling, response waiter cleanup,
  service-swap address validation, SoC device unregister,
  devm-managed IMEM cleanup, timeout classification, signal
  handling, firmware-load serialization, UAPI compatibility, and
  timed-out firmware transaction cleanup.

- Use dma_addr_t for ELE firmware authentication and IMEM service-swap
  buffers, store the encrypted IMEM DMA handle in the IMEM state, and pass
  imem->daddr to IMEM save/restore.

- Reject ELE service-swap addresses whose upper 32 bits are set before
  placing the address into the 32-bit firmware message field.

- Clear waiting_rsp_clbk_hdl state under clbk_rx_lock on all send/receive
  exit paths, including ele_msg_send() failure.

- Keep mailbox TX completion handled by the mailbox controller/core with
  knows_txdone set to false. The i.MX MU controller copies the message
  payload into hardware registers synchronously.

- Move mutable firmware-load and IMEM state to per-device storage in
  struct se_if_priv.

- Register a devres cleanup action to unregister the SoC device returned by
  soc_device_register().

- Remove manual freeing of the devm-managed encrypted IMEM coherent buffer
  from probe cleanup.

- Fix response-wait timeout classification by basing timeout handling on
  the callback handle being waited on, not on command-receiver file context
  identity.

- Use fixed-width UAPI fields and u64_to_user_ptr() to support 32-bit
  userspace compatibility.

- Add compat_ioctl support for the misc-device UAPI.

- Bound userspace-provided message sizes before memdup_user().

- Track timed-out firmware transactions with the corresponding dev_ctx so
  coherent DMA memory is not freed while firmware may still access it.

- Serialize firmware loading state with load_fw_lock to avoid concurrent
  firmware authentication requests.

- Fix get_se_soc_id() to use the correct match-data type.

- Fix command-receiver lifecycle handling by clearing command-receiver
  callback state under clbk_rx_lock and freeing rx_msg only after dropping
  the lock.

- Avoid unbind/remove deadlock by not holding dev_ctx->fops_lock across the
  blocking command-receiver read wait.

- Initialize dev_ctx reference counting with kref_init().

- Add ELE FW API command filtering through ele_uapi_allowed_fw_cmd().

- Move FW API command IDs and FW API-specific state transitions into
  ele_fw_api.c/ele_fw_api.h.

- Allow command-receiver registration/unregistration through the supported
  storage open/close FW API flow.

- Refactor shared-memory slot allocation and rollback in
  se_ioctl_setup_iobuf_handler().

- Fix hsm0 device tree indentation reported by Sashiko.

- Address Lothar Waßmann's review comments:
  - make se_fill_cmd_msg_hdr() return void and remove dead error checks;
  - remove the trailing comma after the final empty of_device_id sentinel.

- Validate the series with checkpatch, sparse, W=1/W=2 builds, coccicheck,
  dt_binding_check for fsl,imx-se.yaml, CHECK_DTBS=y for imx8ulp-evk.dtb,
  and headers_install for include/uapi/linux/se_ioctl.h.

Reference:
- Link to v26: https://lore.kernel.org/r/20260629-imx-se-if-v26-0-146446285744@nxp.com

Changes in v26:
- Folded kernel test robot and Sashiko-bot fixes into the series.
- Added MAILBOX dependency for COMPILE_TEST builds.
- Hardened response waiter timeout handling and late-response processing.
- Serialized command receiver registration and callback-visible receiver state.
- Added iobuf round_up() overflow detection.
- Rolled back iobuf shared-memory reservation on setup failures.
- Bounded userspace-controlled response buffer size.
- Preserved ioctl operation errors across cleanup.
- Added explicit priv/dev_ctx lifetime handling and teardown/open serialization.

Testing:
- checkpatch.pl --strict: no warnings
- sparse: no warnings
- coccicheck on drivers/firmware/imx/: no driver-specific warnings

Reference:
- Link to v25: https://lore.kernel.org/r/20260122-imx-se-if-v25-0-5c3e3e3b69a8@nxp.com

Changes in v25:
5/7
- removes kernel bot reported warning errors.

3/7
- fix checkpatch --strict error.

1/2, 2/7, 4/7, 6/7 & 7/7
- No changes

Reference:
- Link to v24: https://lore.kernel.org/r/20260121-imx-se-if-v24-0-c5222df51cc2@nxp.com

Changes in v24:
5/7 & 3/7
- removes kernel bot reported warning errors.

1/2, 2/7, 4/7, 6/7 & 7/7
- No changes

Reference:
- Link to v23: https://lore.kernel.org/r/20251219-imx-se-if-v23-0-5c6773d00318@nxp.com

Changes in v23:
5/7
- removed un-neccessary 'kfree' from the func se_ioctl_cmd_snd_rcv_rsp_handler().

1/2, 2/7, 3/7, 4/7, 6/7 & 7/7
- No changes

Reference:
- Link to v22: https://lore.kernel.org/r/20251218-imx-se-if-v22-0-07418c872509@nxp.com

Changes in v22:
3/7 & 5/7
- reverted to previous change of using "__free(kfree)", by declare-and-initialize __free() vars next to their allocations.

1/7
- rename the se_fw.c to se_ctrl.c

2/7, 4/7, 5/7 & 7/7
- No changes.

Reference:
- Link to v21: https://lore.kernel.org/r/20251212-imx-se-if-v21-0-ee7d6052d848@nxp.com

Changes in v21:
3/7
- smatch warning fixes.
- Added "COMPILE_TEST" into "depends on IMX_MBOX && ARCH_MXC && ARM64"
- removed "__free(kfree)" & added kfree();

5/7
- removed "__free(kfree)" & added kfree();

1/2, 2/7, 4/7, & 7/7
- No changes

Reference:
- Link to v20: https://lore.kernel.org/r/20251203-imx-se-if-v20-0-a04a25c4255f@nxp.com

Changes in v20:
5/7:
- adds a func "se_chk_tx_msg_hdr", to check the validity of the in-coming message from usersapce.

1/2, 2/7, 3/7, 4/7, 6/7 & 7/7
- No changes

Reference:
- Link to v19: https://lore.kernel.org/r/20250927-imx-se-if-v19-0-d1e7e960c118@nxp.com

Changes in v19:

1/7
- Added 9 lines to the Introduction from line 73-82.

3/7
-  Update the commit message for " For i.MX9x SoC(s) there is at least one
dedicated ELE MU(s) for each world - Linux(one or more) and OP-TEE OS (one or
more), that needs to be shared between them.."

Reference:
- Link to v18: https://lore.kernel.org/r/20250619-imx-se-if-v18-0-c98391ba446d@nxp.com

Changes in v18:

1/7
- Wrap both diagrams above in literal code block by using double-colon

3/7 & 5/7
- Collected Frank's R-b tag.

2/7, 4/7, 6/7 & 7/7
- No changes

Reference:
- Link to v17: https://lore.kernel.org/r/20250426-imx-se-if-v17-0-0c85155a50d1@nxp.com

Changes in v17:
- Changes to 3/7 & 5/7: to wrap code text at 80 character whereever possible.

Reference:
- Link to v16: https://lore.kernel.org/r/20250409-imx-se-if-v16-0-5394e5f3417e@nxp.com

Changes in v16:
- commit 3/7 and 4/7 are moved to end commits making them as 6/7 and 7/7 respectively.
- No change in 1/7 & 2/7.

7/7
- Collected Frank's R-b tag.

6/7
- commit message is updated to wrap at 75 characters.

5/7
- func add_b_desc_to_pending_list, removed the initialization of b_desc to
  NULL.
- variable timeout in func ele_msg_rcv(), is renamed to timeout_ms.
- struct se_if_priv, member variable se_rcv_msg_timeout, is renamed to
  se_rcv_msg_timeout_ms.
- in func load_firmware, move the label exit after dma_free_coherent.

4/7
- commit message is updated to wrap at 75 characters.

3/7
- ele_debug_dump, updated the assignment of keep_logging.
- ele_fw_authenticate function definition is updated to take two address
  as arguments.

Reference:
- Link to v15: https://lore.kernel.org/r/20250407-imx-se-if-v15-0-e3382cecda01@nxp.com

Changes in v15:
- Patch 3/6 is split into two:
  - 3/7: arm64: dts: imx8ulp-evk: add reserved memory property
  - 4/7: arm64: dts: imx8ulp: add nxp secure enclave firmware
- No change in 1/7 & 2/7.

7/7
- removed the se_intance_id structure member variable.
- replace variable name from wait to timeout.
- used 'goto' to follow the common exit path calling "release_firmware(fw);" in case of error path.
- removed TBD string.
- Used ARRAY_SIZE(pending_lists).
- moved init_device_context after init_misc_device_context.
- defined err as long to avoid force convert in func
- added se_rcv_msg_timeout to priv, to control probe/suspend/resume per interface.

6/7
- removed the se_intance_id structure member variable.
- Added dev_ctx to the structure se_clbk_handle, too.
- Collected Frank's R-b tag.

5/7
- removed the se_intance_id structure member variable.
- since added se_if_probe_cleanup to devm, se_if_remove() is redundant. hence removed it.
- rename se_add_msg_chksum to se_get_msg_chksum
- added check if msg-size is 4 byte aligned.
- Fixed multiline comments.
- ele_debug_dump api is updated as part of comment disposition like single setting of flag "keep_logging" & adding if (ret).
- moved dev_err to dev_dbg, for imem save/restore functions.
- moved func get_se_if_name, from 7/7 to here.

3/7
- Updated the commit message.
- split the current patch into two:
  -- 3/7 for board dts, and
  -- 4/7 for chip dts

Reference:
- Link to v14: https://lore.kernel.org/r/20250327-imx-se-if-v14-0-2219448932e4@nxp.com

Changes in v14:

- Patch 5/5 is split into two:
  - firmware: drivers: imx: adds miscdev
  - Introduce dev-ctx dedicated to private.
    -- Base patch before enabling misc-device context, to have the send-receive path, based on device context.
- No change in 1/6 & 2/6.
- Copied change logs from individual commits.

6/6
- moved definition of func se_load_firmware, from 4/6 patch to this patch.
- split init_device_context to init_misc_device_context.
- Different value of se_rcv_msg_timeout is required to be set. Receiving the response of 4K RSA operation can to take upto 3 minutes.
  This long value cannot be set during Linux: boot-up and suspend-resume.
  Hence, it will be set to default small-value during Linux: boot-up and suspend-resume.
- func se_dev_ctx_cpy_out_data(), in either case: do_cpy true or false, the clean-up needs to be done and it is implemented like wise.
  Once do_cpy is false, no need to continue copy to user buffer. But continue to do clean-up. hence cannot return.
  And every dev-ctx operation is done after taking the lock. Hence, two operations with same dev-ctx is not possible in parallel.
- func "init_device_context", for 0th misc dev_ctx, which is created at the time of probe, the device memory management is required. hence there is a difference.
- func "init_device_context", dev_er is replaced with return dev_err_probe.
- func "init_device_context", devm_add_action is replaced by devm_add_action_reset.
- removed type-cast from func se_ioctl_get_se_soc_info_handler().
- used scoped_cond_guard(mutex, _intr, return -EBUSY, &<mutex_lock>)
- combined dev_err & dev_dbg to one dev_err in se_if_fops_read().
- removed the structure member "se_shared_mem_mgmt->secure_mem".

4/6
- trimmed the ele_fetch_soc_info.
- removed the function ptr "se_info->se_fetch_soc_info" and replaced with ele_fetch_soc_info.
- moved definition of func se_load_firmware, to 6/6 patch.
- Different SoC, different ways to fetch soc_info. Generic function declaration for ele_fetch_soc_info() is needed. Hence wrapping ele_get_info() in it.
- Updated Kconfig help text for assertive tone.
- func ele_debug_dump is updated, to remove constructing the format string.
- removed the macro usage for SOC_ID_MASK.
- used low case hex number.
- Condition will never occur, where msg_len satisfy the following condition "msg_len % 4 != 0". Err msg is added if it occurs.
- Function description is added to se_add_msg_crc.
- timeout is added to function ele_msg_rcv, in 5/5 patch.
- local variable "header" is initialized with "tx_msg" and replaced "return err" with "return tx_msg_sz" in func ele_msg_send().
- replace function name from "exception_for_size" to "check_hdr_exception_for_sz"
- replaced "return ret > 0 ? 0 : -1;" with "return ret > 0 ? 0 : ret;" in func "se_save_imem_state".
- func "se_restore_imem_state", to return if the condition is false to proceed.
- removed casting by (void *).
- removed devm_kasprintf and done direct allocatiion for attr->soc_id = "i.MX8ULP" & attr->soc_id = "i.MX8ULP", & attr->family.
- Followed Reverse christmas tree order, whereever missing.
- There is no return if ele_fw_authenticate fails. Execution flow continue forward and execute the fucn dma_free_coherent().
- The loop is not for retry. The loop is needed to load secondary fw followed by loading primary fw, first. This is the case when ELE also got reset.
- dev_err_probe is corrected in func "se_if_request_channel".

3/6
-

Reference:
- Link to v13: https://lore.kernel.org/r/20250311-imx-se-if-v13-0-9cc6d8fd6d1c@nxp.com

Changes in v13:

5/5
- Updated the commit message for imperative mood.
- Remove the usage of macros- NODE_NAME, GET_ASCII_TO_U8, GET_IDX_FROM_DEV_NODE_NAME.
- Clean-up the return path by replacing "ret = -<err>; return ret;" with "return -<err>;"
- Clean-up the return path by replacing "ret = -<err>; goto exit;" with "return -<err>;"
- Removed goto statements from the entire driver, where there is no common code at function's exit.
- Fixes the check-patch erros reported with flag "--strict"
- Replaced devm_add_action, with devm_add_action_or_reset
- Removed the un-necesary and obvious code comments.
- Removed dev_probe_err at the exit of function se_if_probe().

4/5
- Clean-up the return path by replacing "ret = -<err>; return ret;" with "return -<err>;"
- Clean-up the return path by replacing "ret = -<err>; goto exit;" with "return -<err>;"
- Removed goto statements from the entire driver, where there is no common code at function's exit.
- fixes the check-patch erros reported with flag "--strict"
- removed the un-necesary and obvious code comments.
- variable received msg timeout to be different at boot-up & suspend/resume and send/recv ioctlis.

3/5
- compatible string is modified from "fsl,imx8ulp-se" to "fsl,imx8ulp-se-ele-hsm".
- updated the alias name.

2/5
- compatible string is modified from "fsl,imx8ulp-se" to "fsl,imx8ulp-se-ele-hsm".
- compatible string is modified from "fsl,imx93-se" to "fsl,imx93-se-ele-hsm".
- compatible string is modified from "fsl,imx95-se" to "fsl,imx95-se-ele-hsm".
- Mis-understood the +1 from Conor. Hence dropped the Reviewed-by tag.
- Collected Rob's R-b tag on v7 (https://lore.kernel.org/all/172589152997.4184616.5889493628960272898.robh@kernel.org/)

1/5
- No change

Reference:
- Link to v12: https://lore.kernel.org/r/20250120-imx-se-if-v12-0-c5ec9754570c@nxp.com

Changes in v12:

5/5
- increased the wait-timeout.

4/5
- rename flag "handle_susp_resm" to "imem_mgmt"
- moved the buffer allocation ot load_fw->imem.buf, to se_probe_if.
- setting imem state at initialization.

3/5
- No change

2/5
- No change

1/5
- No change

Reference:
- Link to v11: https://lore.kernel.org/r/20241220-imx-se-if-v11-0-0c7e65d7ae7b@nxp.com

Changes in v11:

5/5
- devname is constructed by concatinating get_se_if_name(se_if_id) & se_if_instance_id.
- ele_rcv_msg(), is updated to add the wait_interruptible_timeout for the non-NVM-Daemon message exchanges, such that in case of no response from FW,
  Linux donot hangs.
- added a new helper function get_se_if_name(), to return the secure-enclave interface owner's name string.
- added a new helper function get_se_soc_id(), to return the secure-enclave's SoC id.

4/5
- moved the se_if_node_info member "soc_register", to the struct "se_if_node_info_list"; as soc registration done once, not per interface.
- moved the se_if_node_info member "se_fetch_soc_info", to the struct "se_if_node_info_list"; as soc info fetching is done once, not per interface.
- Added two member variable se_if_id and se_if_instance_id to struct se_if_defines.
- removed the member "se_name" from struct "se_if_node_info". Rather, it will constructed by concatinating get_se_if_name(se_if_id) & se_if_instance_id.
- moved the static global variable "se_version", to the newly created structure "struct se_var_info".
- moved the member "struct se_fw_load_info load_fw" of "se_if_node_info_list", to the newly created structure "struct se_var_info".
- Replaced RUNTIME_PM_OPS with SET_SYSTEM_SLEEP_PM_OPS, in power-managment ops.

3/5
- No change

2/5
- No change

1/5
- No change

Reference:
- Link to v10: https://lore.kernel.org/r/20241104-imx-se-if-v10-0-bf06083cc97f@nxp.com

v10: firmware: imx: driver for NXP secure-enclave

Changes in v10:
5/5
- replaced the u8, u16, u32, u64, with __u8, __u16, __u32, __u64 in
  'include/uapi/linux/se_ioctl.h'.

4/5
- No change

3/5
- No change

2/5
- No change

1/5
- No change

Reference:
- Link to v9: https://lore.kernel.org/r/20241016-imx-se-if-v9-0-fd8fa0c04eab@nxp.com

Changes in v9:

4/5
- change se_if_remove function signature, required after rebase to v6.12-rc1.
- move the info->macros to a structure "struct se_if_defines if_defs".
- Removed "info" from "struct se_if_defines if_defs".
- Moved "mem_pool" from "struct se_if_defines if_defs" to "priv".
- Fetching "info" using container-of.

5/5
- Fetching "info" using container-of.
- Fixed issue reported by sparse.

Reference:
- Link to v8: https://lore.kernel.org/r/20241015-imx-se-if-v8-0-915438e267d3@nxp.com

Changes in v8:

5/5
- Remove the check for SE_IF_CTX_OPENED.
- replaced dev_ctx->priv-dev, priv->dev, whereever possible.
- func "if_misc_deregister" moved before func "init_device_context".
- func "init_device_context" before func "se_ioctl_cmd_snd_rcv_rsp_handler".
- func "se_if_fops_write" and "se_if_fops_read", are moved after func "se_ioctl_get_mu_info".
- non static functions "se_dev_ctx_cpy_out_data, se_dev_ctx_shared_mem_cleanup & init_device_context" are moved static and local scope.
- Removed back & forth between the two structs "struct se_if_device_ctx *dev_ctx" and "struct se_shared_mem_mgmt_info *se_shared_mem_mgmt"
- removed the NULL check for bdesc.
- fops_open, is corrected for acquiring the fops_lock.
- Fops_close, mutex unlock is removed. Infact check for waiting_rsp_clbk_hdl.dev_ctx, is removed.
- sema_init(&dev_ctx->fops_lock, 1);, replaced with Mutex.
- structure member se_notify, is removed.

4/5
- removed initializing err to zero in func ele_fetch_soc_info(),
- replaced 'return 0', with 'goto exit', if the condition (!priv->mem_pool) is true.
- replaced "struct *dev" with "struct se_if_priv *priv", in base_message API(s) and others.
- Created a separate structure "struct se_if_defines" to maintain interface's fixed values like cmd_tag, rsp_tag, success_tag etc.
- removed the macros "WORD_SZ", "SOC_VER_MASK", "DEFAULT_IMX_SOC_VER", "RESERVED_DMA_POOL".
- Added handling for "ctrl+c", by postponing the interrupt, till the response to the "command in flight" is received.
- Removed the mutext lock "se_if_lock".
- furnction prototype for "se_save_imem_state" and "se_restore_imem_state", is changed to pass "imem" by reference.
- Added a new structure "struct se_fw_load_info", dedicated to contain FW loading relevant info. It is a member of struct info_list.
- split "imem_mgmt_file_in_rfs" into two "prim_fw_nm_in_rfs" and "seco_fw_nm_in_rfs", to be part of "struct se_fw_load_info".
- moved the function "se_load_firmware" prior to func "if_mbox_free_channel".
- function "se_load_firmware" is updated to use "request_firmware", instead of "request_firmware_no_wait".
- function "se_load_firmware" is updated to load "primary" fw image, if the imem_state is not BAD. Then load the "secondary FW" image.
- Added a new mutex_lock in the function "se_load_firmware", for ensuring FW loading done once, when there are multiple application are in play.
- instead of "wait_queue_head_t wq", used "sruct completion".
- add devm_add_action with action as se_if_probe_cleanup.

Reference:
- Link to v7: https://lore.kernel.org/r/20240904-imx-se-if-v7-0-5afd2ab74264@nxp.com

Changes in v7:

5/5
- struct se_clbk_handle, is added with a member struct se_if_device_ctx *dev_ctx.
- func call to ele_miscdev_msg_rcv() & ele_miscdev_msg_send(), are removed.
- func se_ioctl_cmd_snd_rcv_rsp_handler(), is modified to remove the func call to ele_miscdev_msg_rcv() & ele_miscdev_msg_send()
- func se_ioctl_cmd_snd_rcv_rsp_handler is callig func ele_msg_send_rcv(), instead.
- Mutext "se_cmd_if_lock", handling is removed from this patch.
- func ele_miscdev_msg_send() is replaced with func ele_msg_send(), in fops_write.
- func ele_miscdev_msg_rcv() is replaced with func ele_msg_rcv(), in fops_read.
- fops_open is modified to create the new dev_ctx instance (using func init_device_context()), which is not registered as miscdev.
- Only one dev_ctx is registered as miscdev and its reference is stored in the struct se_if_priv, as priv_dev_ctx.
- Separate func cleanup_se_shared_mem() & func init_se_shared_mem(), for shared memory handling part of struct dev_ctx.
- Input param for func(s) ele_msg_rcv(), ele_msg_send() & ele_msg_send_rcv(), is replaced from struct se_if_priv to struct se_if_device_ctx.

4/5
- A new structure is defined name struct "se_clbk_handle", to contain members processed in mailbox call-back function.
- "struct se_if_priv" is modified to contain the two structures of "se_clbk_handle" - waiting_rsp_clbk_hdl & cmd_receiver_clbk_hdl.
- func ele_msg_rcv() is modified to take a new additional input reference param "struct se_clbk_handle *se_clbk_hdl".
- func ele_msg_send() is modified to take a new additional input tx_msg_sz.
- func ele_msg_send_rcv(), is modified to take 2 more inputs - tx_msg_sz & exp_rx_msg_sz.
- func se_val_rsp_hdr_n_status(), is modified to take input of rx_msg buffer, instead of header value, as input param.
- each caller of the func ele_msg_send_rcv(), is sending these two additional input params.
- func se_if_callback(), is modified to work on two structures of "se_clbk_handle" - waiting_rsp_clbk_hdl & cmd_receiver_clbk_hdl.
- Variable "max_dev_ctx", is removed from info & priv struture, as well its usage.
- New member variable "se_img_file_to_load", is added to structure "priv".
- Other member variables - rx_msg(ptr), rx_msg_sz, completion done & list of dev_ctxs, is removed from priv struture, along with their usage.
- func se_resume(), updated to wakeup the two "wq", part of "struct se_clbk_handle": priv->waiting_rsp_clbk_hdl & priv->cmd_receiver_clbk_hdl.

3/5
- Node name is changed from senclave-firmware@0 to "secure-enclave"

2/5
- Node name is changed to "secure-enclave".

Reference:
- Link to v6: https://lore.kernel.org/r/20240722-imx-se-if-v6-0-ee26a87b824a@nxp.com

Changes in v6:

5/5
- replaced scope_gaurd with gaurd.

4/5
- replaced scope_gaurd with gaurd.
- remove reading the regs property from dtb.
- Added NULL check for priv data fetched from device, as a sanity check, for ele_base_msg apis)

3/5
- replace firmware with senclave-firmware.

2/5
- replace firmware with senclave-firmware.
- drop description for mbox
- Replaced "items:" with maxItems:1 for "memory-region"
- Replaced "items:" with maxItems:1 for "sram"
- remove regs property.
- remove "$nodename"

Reference:
- Link to v5: https://lore.kernel.org/r/20240712-imx-se-if-v5-0-66a79903a872@nxp.com

Changes in v5:

2/5
- updated the description of mboxes
- updated the description & items for mbox-names.
- updated the description of memory-region
- move "additional properties: false" after allOf block.
- removed other example except one.

4/5
- Corrected the indentation in Kconfig.
- info members:mbox_tx_name & mbox_rx_name, are replaced with macros.

5/5
- Replaced "for  secure enclaves", with "for secure enclaves"
- Replaced "user space" with "userspace".
- End the line "[include]<linux/firmware/imx/ele_mu_ioctl.h>" with a period.

Reference:
- Link to v4: https://lore.kernel.org/r/20240705-imx-se-if-v4-0-52d000e18a1d@nxp.com

Changes in v4:

1/5
a. Removed - from EdgeLock Enclave.

b. Removed , after "Each of the above feature,"

c. replace "can exists" with "can exist".

d.
-messaging units(MU) per SE. Each co-existing 'se' can have one or multiple exclusive
-MU(s), dedicated to itself. None of the MU is shared between two SEs.
+messaging units(MU) per SE. Each co-existing SE can have one or multiple exclusive
+MUs, dedicated to itself. None of the MU is shared between two SEs.
 Communication of the MU is realized using the Linux mailbox driver.

e.
-All those SE interfaces 'se-if' that is/are dedicated to a particular SE, will be
-enumerated and provisioned under the very single 'SE' node.
+Although MU(s) is/are not shared between SE(s). But for SoC like i.MX95 which has
+multiple SE(s) like HSM, V2X-HSM, V2X-SHE; all the SE(s) and their interfaces 'se-if'
+that is/are dedicated to a particular SE will be enumerated and provisioned using the
+single compatible node("fsl,imx95-se").

f. Removed ",". Replaced for "Each 'se-if'," with "Each se-if'.

g. removed ","
-  This layer is responsible for ensuring the communication protocol, that is defined
+  This layer is responsible for ensuring the communication protocol that is defined

h. removed "-"
-  - FW can handle one command-message at a time.
+  - FW can handle one command message at a time.

i.
-  Using these multiple device contexts, that are getting multiplexed over a single MU,
-  user-space application(s) can call fops like write/read to send the command-message,
-  and read back the command-response-message to/from Firmware.
-  fops like read & write uses the above defined service layer API(s) to communicate with
+  Using these multiple device contexts that are getting multiplexed over a single MU,
+  userspace application(s) can call fops like write/read to send the command message,
+  and read back the command response message to/from Firmware.
+  fops like read & write use the above defined service layer API(s) to communicate with
   Firmware.

j. Uppercase for word "Linux".

2/5
a. Rephrased the description to remove list of phandles.

b. Moved required before allOf:
+required:
+  - compatible
+  - reg
+  - mboxes
+  - mbox-names
+
+additionalProperties: false
+
 allOf:

c. replaced not: required: with properties: <property-name>: false.
   # memory-region
-      not:
-        required:
-          - memory-region
+      properties:
+        memory-region: false

   # sram
-    else:
-      not:
-        required:
-          - sram

d. Reduced examples. keeping example of i.MX95.
e. node-name is changed to "firmware@<hex>"

3/5
- node name changed to "firmware@<hex>".

4/5
- used sizeof(*s_info)
- return early, rather than doing goto exit, in ele_get_info().
- Use upper_32_bits() and lower_32_bits()
- use rx_msg here instead of priv->rx_msg
- Moved the status check to validate_rsp_hdr. Rename the function to "se_val_rsp_hdr_n_status"
- typecasting removed header = (struct se_msg_hdr *) msg;
- Converted the API name with prefix imx_ele_* or imx_se_*, to ele_* and se_*, respectively.
- Removed the functions definition & declaration for: free_phybuf_mem_pool() & get_phybuf_mem_pool()
- removed the mbox_free_channel() calls from clean-up.
- Flag "priv->flags" is removed.
- Converted the int se_if_probe_cleanup() to void se_if_probe_cleanup().
- Replaced NULL initialization of structure members: priv->cmd_receiver_dev & priv->waiting_rsp_dev , with comments.
- Removed the function's declaration get_phy_buf_mem_pool1

5/5
Changes to Documentation/ABI/testing/se-cdev.
a. Removed "-" from "secure-enclave" and "file-descriptor".

b. Removed "-" from "shared-library"

c. Replaced "get" with "getting".

d. Added description for the new IOCTL "send command and receive command response"

e. Replaced "wakeup_intruptible" with "wait_event_interruptible"

f. Removed ";"

g. Removd "," from "mailbox_lock,"

h. Replaced "free" with "frees"

i. In mailbox callback function, checking the buffer size before
copying.

Reference:
- Link to v3: https://lore.kernel.org/r/20240617-imx-se-if-v3-0-a7d28dea5c4a@nxp.com

Changes in v3:
5/5:
- Initialize tx_msg with NULL.
- memdup_user() returns an error pointer, not NULL. correct it by adding check for err_ptr.
- new IOCTL is added to send & recieve the message.
- replaced the while loop till list is empty, with list_for_each_entry.
- replaced __list_del_entry, with list_del.
- Removed the dev_err message from copy to user.
- Removed the casting of void *.
- corrected the typcasting in copy to user.
- removed un-necessary goto statement.
- Removed dead code for clean-up of memory.
- Removed un-mapping of secured memory
- Passing se_if_priv structure to init_device_context.
- Updated the below check to replace io.length with round_up(io.length).
	if (shared_mem->size < shared_mem->pos|| io.length >= shared_mem->size - shared_mem->pos)
- Created a function to cleanup the list of shared memory buffers.
- Used list_for_each_entry_safe(). created a separate functions: se_dev_ctx_cpy_out_data() & se_dev_ctx_shared_mem_cleanup()

4/5
- Changed the compatible string to replace "-ele", to "-se".
- Declaration of imx_se_node_info, is done as const in the whole file
- Remove the unused macros from ele_base_msg.h
- Remove the function declaration get_phy_buf_mem_pool1, from the header file.
- Replace the use of dmam_alloc_coherent to dma_alloc_coherent
- Check for function pointer, before calling the fucntion pointer in imx_fetch_se_soc_info
- Removed the unused flag for SE_MU_IO_FLAGS_USE_SEC_MEM.
-  Removed the unused macros WORD_SZ
- instead of struct device *dev, struct se_if_priv *priv, is used as argument to the funtions:se_save_imem_state, se_restore_imem_state, imx_fetch_se_soc_info
- Removed ret from validate_rsp_hdr.
- changed the prefix of the funtion: plat_add_msg_crc and plat_fill_cmd_msg_hdr.
- indentation correction for info structures.
- remove the check for priv not null from se_if_probe_cleanup
- Removed the casting of void *.
- se_load_firmware function is corrected for not freeing the buffer when allocation fails.
- Checking if get_imx_se_node_info() can return NULL, in se_if_probe()
- imem.size has type u32. return value from se_save_imem_state() will be assigned to imem.size in case of success only.
- removed the flag un-setting in case of failure. priv->flags &= (~RESERVED_DMA_POOL);
- removed the function call for devm_of_platform_populate(dev);
- Checking for not-NULL,  before calling the funtion pointer se_fetch_soc_info.
- Removed the checking for reserved memory flag, before freeing up the reserved memory, in se_probe_if_cleanup.

3/5
- Changed the compatible string to replace "-ele", to "-se".

2/5
- to fix the warning error, replaced the "-ele" & "-v2x" in compatible string, to "-se".
- Added an example for ele@0 for compatible string "fsl,imx95-se"

Reference
- Link to v2: https://lore.kernel.org/r/20240523-imx-se-if-v2-0-5a6fd189a539@nxp.com

Changes in v2:

4/4
- Split this patch into two: 1. base driver & 2. Miscdev
- Initialize the return variable "err" as 0, before calling 'return err', in the file ele_common.c
- Fix the usage of un-iniitialized pointer variable, by initializing them with NULL, in ele_base_msg.c.
- Fix initializing the ret variable, to return the correct error code in case of issue.
- replaced dmam_alloc_coherent with dma_alloc_coherent.
- Replace the use of ELE_GET_INFO_READ_SZ, with sizeof(soc_info).
- Replaced -1 with -EPERM
- Removed the safety check on func-input param, in ele_get_info().
- fix the assigning data[1] with lower 32 address, rather than zero, for ele_fw_authenticate API.
- Correctly initializing the function's return error code, for file  ele_base_msg.c.
- replaced 'return' with 'goto'.
- Use length in bytes.
- Corrected the structure se_msg_hdr.
- Moved setting of rx_msg  to priv, into the function imx_ele_msg_send_rcv
- Will add lockdep_assert_held, to receive path, in v2.
- corrected the spacing at "ret  = validate_rsp_hdr"
- FIELD_GET() used for RES_STATUS
- Re-write the structure soc_info, matching the information provided in response to this api.
- The "|" goes to the end of the previous line.
- Moved the locking and unlocking of the command lock to the caller of the function.
- removed the safety check for device private data.
- Structure memory reference, used to read message header.
- In the interrupt call back function, remove assigning waiting_rsp_dev to NULL, in case of response message rcv from FW.
- do while removed.
- replaced BIT(1) for RESERVED_DMA_POOL, to BIT(0)
- The backslash is removed while assigning the file name with absolute path to structure variable.fw_name_in_rfs =.
- Update the 'if' condition by removing "idx < 0".
- mbox_request_channel_byname() uses a "char" for the name not a u8. Corrected.
- devm managed resources, are not cleaned now, in function se_probe_if_cleanup
- Used dev_err_probe().
- Used %pe to print error string.
- remove "__maybe_unused" for "struct platform_device *enum_plat_dev __maybe_unused;"
- used FIELD_GET(), for  RES_STATUS. Removed the use of MSG_TAG, MSG_COMMAND, MSG_SIZE, MSG_VER.
- Depricated the used of member of struct se_if_priv, bool no_dev_ctx_used;
- Moved the text explaing the synchronization logic via mutexes, from patch 1/4 to se_ctrl.h.
- removed the type casting of info_list = (struct imx_se_node_info_list *) device_get_match_data(dev->parent);
- Used static variable priv->soc_rev in the se_ctrl.c, replaced the following condition: if (info_list->soc_rev) to if (priv->soc_rev) for checking if this flow is already executed or not.
- imx_fetch_soc_info will return failure if the get_info function fails.
- Removed devm_free from imx_fetch_soc_info too.

3/3
- Made changes to move all the properties to parent node, without any child node.

2/4
- Use Hex pattern string.
- Move the properties to parent node, with no child node.
- Add i.MX95-ele to compatible nodes to fix the warning "/example-2/v2x: failed to match any schema with compatible: ['fsl,imx95-v2x']"

1/1
- Corrected the spelling from creats to creates.
- drop the braces around the plural 's' for interfaces
- written se in upper case SE.
- Replace "multiple message(s)" with messages.
- Removed too much details about locks.

Testing
- make CHECK_DTBS=y freescale/imx8ulp-evk.dtb;
- make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j8  dt_binding_check DT_SCHEMA_FILES=fsl,imx-se.yaml
- make C=1 CHECK=scripts/coccicheck drivers/firmware/imx/*.* W=1 > r.txt
- ./scripts/checkpatch.pl --git <>..HEAD
- Tested the Image and .dtb, on the i.MX8ULP.

Reference
- Link to v1: https://lore.kernel.org/r/20240510-imx-se-if-v1-0-27c5a674916d@nxp.com

---
Pankaj Gupta (7):
      Documentation/firmware: add imx/se to other_interfaces
      dt-bindings: arm: fsl: add imx-se-fw binding doc
      firmware: imx: add driver for NXP EdgeLock Enclave
      firmware: imx: device context dedicated to priv
      firmware: imx: adds miscdev
      arm64: dts: imx8ulp: add secure enclave node
      arm64: dts: imx8ulp: add reserved memory for EdgeLock Enclave

 Documentation/ABI/testing/se-cdev                  |   44 +
 .../devicetree/bindings/firmware/fsl,imx-se.yaml   |   91 +
 .../driver-api/firmware/other_interfaces.rst       |  133 ++
 arch/arm64/boot/dts/freescale/imx8ulp-evk.dts      |    3 +-
 .../arm64/boot/dts/freescale/imx8ulp-firmware.dtsi |   31 +
 arch/arm64/boot/dts/freescale/imx8ulp.dtsi         |   12 +-
 drivers/firmware/imx/Kconfig                       |   12 +
 drivers/firmware/imx/Makefile                      |    2 +
 drivers/firmware/imx/ele_base_msg.c                |  327 +++
 drivers/firmware/imx/ele_base_msg.h                |  119 ++
 drivers/firmware/imx/ele_common.c                  |  615 ++++++
 drivers/firmware/imx/ele_common.h                  |   50 +
 drivers/firmware/imx/ele_fw_api.c                  |  186 ++
 drivers/firmware/imx/ele_fw_api.h                  |   29 +
 drivers/firmware/imx/se_ctrl.c                     | 2105 ++++++++++++++++++++
 drivers/firmware/imx/se_ctrl.h                     |  211 ++
 include/linux/firmware/imx/se_api.h                |   14 +
 include/uapi/linux/se_ioctl.h                      |   97 +
 18 files changed, 4078 insertions(+), 3 deletions(-)
---
base-commit: f5098b6bae761e346ebcd9da7f95622c04733cff
change-id: 20240507-imx-se-if-a40055093dc6

Best regards,
-- 
Pankaj Gupta <pankaj.gupta@nxp.com>

[PATCH v34 1/7] Documentation/firmware: add imx/se to other_interfaces

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Documents i.MX SoC's Service layer and C_DEV driver for selected SoC(s)
that contains the NXP hardware IP(s) for Secure Enclaves(se) like:
- NXP EdgeLock Enclave on i.MX93 & i.MX8ULP

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 .../driver-api/firmware/other_interfaces.rst       | 133 +++++++++++++++++++++
 1 file changed, 133 insertions(+)

diff --git a/Documentation/driver-api/firmware/other_interfaces.rst b/Documentation/driver-api/firmware/other_interfaces.rst
index 06ac89adaafb..6c6fa9a0ba1d 100644
--- a/Documentation/driver-api/firmware/other_interfaces.rst
+++ b/Documentation/driver-api/firmware/other_interfaces.rst
@@ -49,3 +49,136 @@ of the requests on to a secure monitor (EL3).
 
 .. kernel-doc:: drivers/firmware/stratix10-svc.c
    :export:
+
+NXP Secure Enclave Firmware Interface
+=====================================
+
+Introduction
+------------
+The NXP's i.MX HW IP like EdgeLock Enclave, V2X etc., creates an embedded secure
+enclave within the SoC boundary to enable features like:
+
+- Hardware Security Module (HSM)
+- Security Hardware Extension (SHE)
+- Vehicular to Anything (V2X)
+
+Each of the above features is enabled through dedicated NXP H/W IP on the SoC.
+On a single SoC, multiple hardware IP (or can say more than one secure enclave)
+can exist.
+
+NXP SoCs enabled with the such secure enclaves(SEs) IPs are:
+i.MX93, i.MX8ULP
+
+To communicate with one or more co-existing SE(s) on SoC, there is/are dedicated
+messaging units(MU) per SE. Each co-existing SE can have one or multiple exclusive
+MUs, dedicated to itself. None of the MU is shared between two SEs. Communication
+of the MU is realized using the mailbox driver. Each secure enclave can cater to
+multiple clients by virtue of these exclusive MUs. Also, they can distinguish
+transactions originating from these clients based on the MU used and core security
+state. The communication between the clients and secure enclaves is in the form of
+a command/response mechanism. Each client could expose a specific set of secure enclave
+features to the higher layers, based on the commands supported by that client. For
+example, the secure enclave could simultaneously support an OPTEE TA and Linux
+middleware as clients. Each of these clients can expose a specific set of secure
+enclave features based on the command set supported by them.
+
+NXP Secure Enclave(SE) Interface
+--------------------------------
+MU(s) is/are not shared between SE(s). But for an SoC like i.MX95 which has
+multiple SE(s) like HSM, V2X-HSM, V2X-SHE, all the SE(s) and their interfaces 'se-if'
+that is/are dedicated to a particular SE will be enumerated and provisioned using the
+single compatible node("fsl,imx95-se").
+
+Each 'se-if' comprises two layers:
+
+- (C_DEV Layer) User-Space software-access interface.
+- (Service Layer) OS-level software-access interface.
+
+::
+
+   +--------------------------------------------+
+   |            Character Device(C_DEV)         |
+   |                                            |
+   |   +---------+ +---------+     +---------+  |
+   |   | misc #1 | | misc #2 | ... | misc #n |  |
+   |   |  dev    | |  dev    |     | dev     |  |
+   |   +---------+ +---------+     +---------+  |
+   |        +-------------------------+         |
+   |        | Misc. Dev Synchr. Logic |         |
+   |        +-------------------------+         |
+   |                                            |
+   +--------------------------------------------+
+
+   +--------------------------------------------+
+   |               Service Layer                |
+   |                                            |
+   |      +-----------------------------+       |
+   |      | Message Serialization Logic |       |
+   |      +-----------------------------+       |
+   |          +---------------+                 |
+   |          |  imx-mailbox  |                 |
+   |          |   mailbox.c   |                 |
+   |          +---------------+                 |
+   |                                            |
+   +--------------------------------------------+
+
+- service layer:
+  This layer is responsible for ensuring the communication protocol that is defined
+  for communication with firmware.
+
+  FW Communication protocol ensures two things:
+
+  - Serializing the messages to be sent over an MU.
+  - FW can handle one command message at a time.
+
+- c_dev:
+  This layer offers character device contexts, created as '/dev/<se>_mux_chx'.
+  Using these multiple device contexts that are multiplexed over a single MU,
+  userspace application(s) can call fops like write/read to send the command message,
+  and read back the command response message to/from Firmware.
+  fops like read & write use the above defined service layer API(s) to communicate with
+  Firmware.
+
+  Misc-device(/dev/<se>_mux_chn) synchronization protocol::
+
+                                Non-Secure               +   Secure
+                                                         |
+                                                         |
+                +-----------+      +-------------+       |
+                | se_ctrl.c +<---->+imx-mailbox.c|       |
+                |           |      |  mailbox.c  +<-->+------+    +------+
+                +-----+-----+      +-------------+    | MU X +<-->+ ELE |
+                      |                               +------+    +------+
+                      +----------------+                 |
+                      |                |                 |
+                      v                v                 |
+                  logical           logical              |
+                  receiver          waiter               |
+                     +                 +                 |
+                     |                 |                 |
+                     |                 |                 |
+                     |            +----+------+          |
+                     |            |           |          |
+                     |            |           |          |
+              device_ctx     device_ctx     device_ctx   |
+                                                         |
+                User 0        User 1       User Y        |
+                +------+      +------+     +------+      |
+                |misc.c|      |misc.c|     |misc.c|      |
+   kernel space +------+      +------+     +------+      |
+                                                         |
+   +---------------------------------------------------- |
+                    |             |           |          |
+   userspace   /dev/ele_muXch0    |           |          |
+                          /dev/ele_muXch1     |          |
+                                        /dev/ele_muXchY  |
+                                                         |
+
+When a user sends a command to the firmware, it registers its device_ctx
+as waiter of a response from firmware.
+
+Enclave's Firmware owns the storage management over a Linux filesystem.
+For this c_dev provisions a dedicated slave device called "receiver".
+
+.. kernel-doc:: drivers/firmware/imx/se_ctrl.c
+   :export:

-- 
2.43.0

Re: [PATCH v34 1/7] Documentation/firmware: add imx/se to other_interfaces

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The kernel-doc directive references a non-existent file 'drivers/firmware/imx/se_ctrl.c', which breaks documentation builds.
--

--- Patch [1]: [PATCH v34 1/7] Documentation/firmware: add imx/se to other_interfaces ---
commit 2a1a9962f9352382d58e5f7ad151d5b2fd1a395f
Author: Pankaj Gupta <pankaj.gupta@nxp.com>

Documentation/firmware: add imx/se to other_interfaces

Documents the i.MX SoC Service layer and C_DEV driver for selected SoCs
containing NXP hardware IPs for Secure Enclaves.

> diff --git a/Documentation/driver-api/firmware/other_interfaces.rst b/Documentation/driver-api/firmware/other_interfaces.rst
> --- a/Documentation/driver-api/firmware/other_interfaces.rst
> +++ b/Documentation/driver-api/firmware/other_interfaces.rst
[ ... ]
> +When a user sends a command to the firmware, it registers its device_ctx
> +as waiter of a response from firmware.
> +
> +Enclave's Firmware owns the storage management over a Linux filesystem.
> +For this c_dev provisions a dedicated slave device called "receiver".
> +
> +.. kernel-doc:: drivers/firmware/imx/se_ctrl.c
> +   :export:

[Severity: Low]
Does drivers/firmware/imx/se_ctrl.c exist in the source tree at this commit? 
It appears this directive references a file that is not present, which will 
cause warnings or failures during documentation builds.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-imx-se-if-v34-0-7e4713d14e0a@nxp.com?part=1

[PATCH v34 2/7] dt-bindings: arm: fsl: add imx-se-fw binding doc

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

The NXP security hardware IP(s) like: i.MX EdgeLock Enclave, V2X etc.,
creates an embedded secure enclave within the SoC boundary to enable
features like:
- HSM
- SHE
- V2X

Secure-Enclave(s) communication interface are typically via message
unit, i.e., based on mailbox linux kernel driver. This driver enables
communication ensuring well defined message sequence protocol between
Application Core and enclave's firmware.

Driver configures multiple misc-device on the MU, for multiple
user-space applications, to be able to communicate over single MU.

It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 .../devicetree/bindings/firmware/fsl,imx-se.yaml   | 91 ++++++++++++++++++++++
 1 file changed, 91 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml b/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml
new file mode 100644
index 000000000000..fa81adbf9b80
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml
@@ -0,0 +1,91 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/fsl,imx-se.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP i.MX HW Secure Enclave(s) EdgeLock Enclave
+
+maintainers:
+  - Pankaj Gupta <pankaj.gupta@nxp.com>
+
+description: |
+  NXP's SoC may contain one or multiple embedded secure-enclave HW
+  IP(s) like i.MX EdgeLock Enclave, V2X etc. These NXP's HW IP(s)
+  enables features like
+    - Hardware Security Module (HSM),
+    - Security Hardware Extension (SHE), and
+    - Vehicular to Anything (V2X)
+
+  Communication interface to the secure-enclaves(se) is based on the
+  messaging unit(s).
+
+properties:
+  compatible:
+    enum:
+      - fsl,imx8ulp-se-ele-hsm
+      - fsl,imx93-se-ele-hsm
+      - fsl,imx95-se-ele-hsm
+
+  mboxes:
+    items:
+      - description: mailbox phandle to send message to se firmware
+      - description: mailbox phandle to receive message from se firmware
+
+  mbox-names:
+    items:
+      - const: tx
+      - const: rx
+
+  memory-region:
+    maxItems: 1
+
+  sram:
+    maxItems: 1
+
+required:
+  - compatible
+  - mboxes
+  - mbox-names
+
+allOf:
+  # memory-region
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - fsl,imx8ulp-se-ele-hsm
+              - fsl,imx93-se-ele-hsm
+    then:
+      required:
+        - memory-region
+    else:
+      properties:
+        memory-region: false
+
+  # sram
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - fsl,imx8ulp-se-ele-hsm
+    then:
+      required:
+        - sram
+
+    else:
+      properties:
+        sram: false
+
+additionalProperties: false
+
+examples:
+  - |
+    secure-enclave {
+      compatible = "fsl,imx95-se-ele-hsm";
+      mboxes = <&ele_mu0 0 0>, <&ele_mu0 1 0>;
+      mbox-names = "tx", "rx";
+    };
+...

-- 
2.43.0

[PATCH v34 3/7] firmware: imx: add driver for NXP EdgeLock Enclave

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Add MU-based communication interface for secure enclave.

NXP hardware IP(s) for secure-enclaves like Edgelock Enclave(ELE), are
embedded in the SoC to support the features like HSM, SHE & V2X, using
message based communication interface.

The secure enclave FW communicates with Linux over single or multiple
dedicated messaging unit(MU) based interface(s).
Exists on i.MX SoC(s) like i.MX8ULP, i.MX93, i.MX95 etc.

For i.MX9x SoC(s) there is at least one dedicated ELE MU(s) for each
world - Linux(one or more) and OPTEE-OS (one or more).

Other dependent kernel drivers will be:
- NVMEM: that supports non-volatile devices like EFUSES,
  managed by NXP's secure-enclave.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
Changes from v32 to v33
- Sample jiffies once. jiffies is volatile, so reading
  it separately for the deadline check and for the
  remaining-time subtraction would be a TOCTOU: a timer
  tick (or a NO_HZ/virtualized tick catch-up that jumps
  jiffies by several ticks) landing between the two
  reads could push jiffies past the deadline and make
  deadline_jiffies - jiffies underflow to a near
  ULONG_MAX timeout, hanging the wait. One snapshot
  keeps both uses consistent, so now < deadline_jiffies
  guarantees a strictly positive remainder.

Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260121-imx-se-if-v32-0-c5222df51cc2@nxp.com?part=3
---
 drivers/firmware/imx/Kconfig        |  12 +
 drivers/firmware/imx/Makefile       |   2 +
 drivers/firmware/imx/ele_base_msg.c | 282 ++++++++++++++++++++
 drivers/firmware/imx/ele_base_msg.h | 100 +++++++
 drivers/firmware/imx/ele_common.c   | 492 ++++++++++++++++++++++++++++++++++
 drivers/firmware/imx/ele_common.h   |  45 ++++
 drivers/firmware/imx/se_ctrl.c      | 507 ++++++++++++++++++++++++++++++++++++
 drivers/firmware/imx/se_ctrl.h      | 112 ++++++++
 include/linux/firmware/imx/se_api.h |  14 +
 9 files changed, 1566 insertions(+)

diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig
index 127ad752acf8..93ac339800e2 100644
--- a/drivers/firmware/imx/Kconfig
+++ b/drivers/firmware/imx/Kconfig
@@ -55,3 +55,15 @@ config IMX_SCMI_MISC_DRV
 	  core that could provide misc functions such as board control.
 
 	  This driver can also be built as a module.
+
+config IMX_SEC_ENCLAVE
+	tristate "i.MX Embedded Secure Enclave - EdgeLock Enclave Firmware driver."
+	depends on MAILBOX && ((IMX_MBOX && ARCH_MXC && ARM64) || COMPILE_TEST)
+	select FW_LOADER
+	default m if ARCH_MXC
+
+	help
+	  Exposes APIs supported by the iMX Secure Enclave HW IP called:
+	  - EdgeLock Enclave Firmware (for i.MX8ULP, i.MX93),
+	    like base, HSM, V2X & SHE using the SAB protocol via the shared Messaging
+	    Unit.
diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 3bbaffa6e347..4412b15846b1 100644
--- a/drivers/firmware/imx/Makefile
+++ b/drivers/firmware/imx/Makefile
@@ -4,3 +4,5 @@ obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o imx-scu-irq.o rm.o imx-scu-soc.o
 obj-${CONFIG_IMX_SCMI_CPU_DRV}	+= sm-cpu.o
 obj-${CONFIG_IMX_SCMI_MISC_DRV}	+= sm-misc.o
 obj-${CONFIG_IMX_SCMI_LMM_DRV}	+= sm-lmm.o
+sec_enclave-objs		= se_ctrl.o ele_common.o ele_base_msg.o
+obj-${CONFIG_IMX_SEC_ENCLAVE}	+= sec_enclave.o
diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
new file mode 100644
index 000000000000..724f6e913ce7
--- /dev/null
+++ b/drivers/firmware/imx/ele_base_msg.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2025 NXP
+ */
+
+#include <linux/types.h>
+
+#include <linux/cleanup.h>
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/genalloc.h>
+
+#include "ele_base_msg.h"
+#include "ele_common.h"
+
+#define FW_DBG_DUMP_FIXED_STR		"ELE"
+
+static void ele_get_info_cleanup(struct se_if_priv *priv, u32 *buf, dma_addr_t d_addr,
+				 size_t size)
+{
+	if (priv->mem_pool)
+		gen_pool_free(priv->mem_pool, (unsigned long)buf, size);
+	else
+		dma_free_coherent(priv->dev, size, buf, d_addr);
+}
+
+int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
+{
+	dma_addr_t get_info_addr = 0;
+	void *get_info_data = NULL;
+	u32 get_info_len;
+	int ret = 0;
+
+	if (!priv)
+		return -EINVAL;
+
+	memset(s_info, 0x0, sizeof(*s_info));
+
+	struct se_api_msg *tx_msg __free(kfree) =
+		kzalloc(ELE_GET_INFO_REQ_MSG_SZ, GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	struct se_api_msg *rx_msg __free(kfree) =
+		kzalloc(ELE_GET_INFO_RSP_MSG_SZ, GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	get_info_len = ELE_GET_INFO_BUFF_SZ;
+	if (priv->mem_pool)
+		get_info_data = gen_pool_dma_alloc(priv->mem_pool,
+						   get_info_len,
+						   &get_info_addr);
+	else
+		get_info_data = dma_alloc_coherent(priv->dev,
+						   get_info_len,
+						   &get_info_addr,
+						   GFP_KERNEL);
+	if (!get_info_data) {
+		dev_err(priv->dev,
+			"%s: Failed to allocate get_info_addr.", __func__);
+		return -ENOMEM;
+	}
+
+	/* gen_pool_dma_alloc() does not zero the buffer. */
+	memset(get_info_data, 0, get_info_len);
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_GET_INFO_REQ, ELE_GET_INFO_REQ_MSG_SZ, true);
+
+	tx_msg->data[0] = upper_32_bits(get_info_addr);
+	tx_msg->data[1] = lower_32_bits(get_info_addr);
+	tx_msg->data[2] = sizeof(*s_info);
+	ret = ele_msg_send_rcv(priv, tx_msg, ELE_GET_INFO_REQ_MSG_SZ, rx_msg,
+			       ELE_GET_INFO_RSP_MSG_SZ);
+	if (ret < 0) {
+		ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);
+		return ret;
+	}
+
+	ret = se_val_rsp_hdr_n_status(priv, rx_msg, ELE_GET_INFO_REQ,
+				      ELE_GET_INFO_RSP_MSG_SZ, true);
+	if (ret < 0) {
+		ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);
+		return ret;
+	}
+
+	memcpy(s_info, get_info_data, sizeof(*s_info));
+
+	ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);
+
+	return ret;
+}
+
+int ele_fetch_soc_info(struct se_if_priv *priv, void *data)
+{
+	return ele_get_info(priv, (struct ele_dev_info *)data);
+}
+
+int ele_ping(struct se_if_priv *priv)
+{
+	int ret = 0;
+
+	if (!priv)
+		return -EINVAL;
+
+	struct se_api_msg *tx_msg __free(kfree) = kzalloc(ELE_PING_REQ_SZ,
+							  GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	struct se_api_msg *rx_msg __free(kfree) = kzalloc(ELE_PING_RSP_SZ,
+							  GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_PING_REQ, ELE_PING_REQ_SZ, true);
+
+	ret = ele_msg_send_rcv(priv, tx_msg, ELE_PING_REQ_SZ, rx_msg,
+			       ELE_PING_RSP_SZ);
+	if (ret < 0)
+		return ret;
+
+	ret = se_val_rsp_hdr_n_status(priv, rx_msg, ELE_PING_REQ,
+				      ELE_PING_RSP_SZ, true);
+
+	return ret;
+}
+
+int ele_service_swap(struct se_if_priv *priv,
+		     dma_addr_t addr,
+		     u32 addr_size, u16 flag)
+{
+	int ret = 0;
+
+	if (!priv)
+		return -EINVAL;
+
+	if (upper_32_bits(addr)) {
+		dev_err(priv->dev,
+			"ELE service-swap address exceeds 32-bit range: %pad\n",
+			&addr);
+		return -ERANGE;
+	}
+
+	struct se_api_msg *tx_msg __free(kfree)	=
+		kzalloc(ELE_SERVICE_SWAP_REQ_MSG_SZ, GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	struct se_api_msg *rx_msg __free(kfree) =
+		kzalloc(ELE_SERVICE_SWAP_RSP_MSG_SZ, GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_SERVICE_SWAP_REQ, ELE_SERVICE_SWAP_REQ_MSG_SZ, true);
+
+	tx_msg->data[0] = flag;
+	tx_msg->data[1] = addr_size;
+	tx_msg->data[2] = ELE_NONE_VAL;
+	tx_msg->data[3] = lower_32_bits(addr);
+	ret = se_update_msg_chksum((u32 *)&tx_msg[0], ELE_SERVICE_SWAP_REQ_MSG_SZ);
+	if (ret)
+		return -EINVAL;
+
+	ret = ele_msg_send_rcv(priv, tx_msg, ELE_SERVICE_SWAP_REQ_MSG_SZ,
+			       rx_msg, ELE_SERVICE_SWAP_RSP_MSG_SZ);
+	if (ret < 0)
+		return ret;
+
+	ret = se_val_rsp_hdr_n_status(priv, rx_msg, ELE_SERVICE_SWAP_REQ,
+				      ELE_SERVICE_SWAP_RSP_MSG_SZ, true);
+	if (ret)
+		return ret;
+
+	if (flag == ELE_IMEM_EXPORT)
+		ret = rx_msg->data[1];
+	else
+		ret = 0;
+
+	return ret;
+}
+
+int ele_fw_authenticate(struct se_if_priv *priv, dma_addr_t contnr_addr,
+			dma_addr_t img_addr)
+{
+	int ret = 0;
+
+	if (!priv)
+		return -EINVAL;
+
+	if (upper_32_bits(contnr_addr) || upper_32_bits(img_addr)) {
+		dev_err(priv->dev, "Wrong address: %pap %pap\n", &contnr_addr, &img_addr);
+		return -EINVAL;
+	}
+
+	struct se_api_msg *tx_msg __free(kfree)	=
+		kzalloc(ELE_FW_AUTH_REQ_SZ, GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	struct se_api_msg *rx_msg __free(kfree) =
+		kzalloc(ELE_FW_AUTH_RSP_MSG_SZ, GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_FW_AUTH_REQ, ELE_FW_AUTH_REQ_SZ, true);
+
+	tx_msg->data[0] = lower_32_bits(contnr_addr);
+	tx_msg->data[1] = 0;
+	tx_msg->data[2] = lower_32_bits(img_addr);
+
+	ret = ele_msg_send_rcv(priv, tx_msg, ELE_FW_AUTH_REQ_SZ, rx_msg,
+			       ELE_FW_AUTH_RSP_MSG_SZ);
+	if (ret < 0)
+		return ret;
+
+	ret = se_val_rsp_hdr_n_status(priv, rx_msg, ELE_FW_AUTH_REQ,
+				      ELE_FW_AUTH_RSP_MSG_SZ, true);
+
+	return ret;
+}
+
+int ele_debug_dump(struct se_if_priv *priv)
+{
+	bool keep_logging;
+	int msg_ex_cnt;
+	int ret = 0;
+	int i;
+
+	if (!priv)
+		return -EINVAL;
+
+	struct se_api_msg *tx_msg __free(kfree) = kzalloc(ELE_DEBUG_DUMP_REQ_SZ,
+							  GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	struct se_api_msg *rx_msg __free(kfree)	= kzalloc(ELE_DEBUG_DUMP_RSP_SZ,
+							  GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, &tx_msg->header, ELE_DEBUG_DUMP_REQ,
+			    ELE_DEBUG_DUMP_REQ_SZ, true);
+
+	msg_ex_cnt = 0;
+	do {
+		memset(rx_msg, 0x0, ELE_DEBUG_DUMP_RSP_SZ);
+
+		ret = ele_msg_send_rcv(priv, tx_msg, ELE_DEBUG_DUMP_REQ_SZ,
+				       rx_msg, ELE_DEBUG_DUMP_RSP_SZ);
+		if (ret < 0)
+			return ret;
+
+		ret = se_val_rsp_hdr_n_status(priv, rx_msg, ELE_DEBUG_DUMP_REQ,
+					      ELE_DEBUG_DUMP_RSP_SZ, true);
+		if (ret) {
+			dev_err(priv->dev, "Dump_Debug_Buffer Error: %x.", ret);
+			break;
+		}
+		keep_logging = (rx_msg->header.size >= (ELE_DEBUG_DUMP_RSP_SZ >> 2) &&
+				msg_ex_cnt < ELE_MAX_DBG_DMP_PKT);
+
+		rx_msg->header.size -= 2;
+
+		if (rx_msg->header.size > 2)
+			rx_msg->header.size--;
+
+		for (i = 0; i < rx_msg->header.size; i += 2)
+			dev_info(priv->dev, "%s%02x_%02x: 0x%08x 0x%08x",
+				 FW_DBG_DUMP_FIXED_STR,	msg_ex_cnt, i,
+				 rx_msg->data[i + 1], rx_msg->data[i + 2]);
+
+		msg_ex_cnt++;
+	} while (keep_logging);
+
+	return ret;
+}
diff --git a/drivers/firmware/imx/ele_base_msg.h b/drivers/firmware/imx/ele_base_msg.h
new file mode 100644
index 000000000000..d532c3f49449
--- /dev/null
+++ b/drivers/firmware/imx/ele_base_msg.h
@@ -0,0 +1,100 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2025 NXP
+ *
+ * Header file for the EdgeLock Enclave Base API(s).
+ */
+
+#ifndef ELE_BASE_MSG_H
+#define ELE_BASE_MSG_H
+
+#include <linux/unaligned.h>
+#include <linux/device.h>
+#include <linux/types.h>
+
+#include "se_ctrl.h"
+
+#define ELE_NONE_VAL			0x0
+
+#define ELE_GET_INFO_REQ		0xda
+#define ELE_GET_INFO_REQ_MSG_SZ		0x10
+#define ELE_GET_INFO_RSP_MSG_SZ		0x08
+
+#define MAX_UID_SIZE                     (16)
+#define DEV_GETINFO_ROM_PATCH_SHA_SZ     (32)
+#define DEV_GETINFO_FW_SHA_SZ            (32)
+#define DEV_GETINFO_OEM_SRKH_SZ          (64)
+#define DEV_GETINFO_MIN_VER_MASK	0xff
+#define DEV_GETINFO_MAJ_VER_MASK	0xff00
+#define ELE_DEV_INFO_EXTRA_SZ		0x60
+
+struct dev_info {
+	u8  cmd;
+	u8  ver;
+	u16 length;
+	u16 soc_id;
+	u16 soc_rev;
+	u16 lmda_val;
+	u8  ssm_state;
+	u8  dev_atts_api_ver;
+	u8  uid[MAX_UID_SIZE];
+	u8  sha_rom_patch[DEV_GETINFO_ROM_PATCH_SHA_SZ];
+	u8  sha_fw[DEV_GETINFO_FW_SHA_SZ];
+};
+
+struct dev_addn_info {
+	u8  oem_srkh[DEV_GETINFO_OEM_SRKH_SZ];
+	u8  trng_state;
+	u8  csal_state;
+	u8  imem_state;
+	u8  reserved2;
+};
+
+struct ele_dev_info {
+	struct dev_info d_info;
+	struct dev_addn_info d_addn_info;
+};
+
+#define ELE_GET_INFO_BUFF_SZ		(sizeof(struct ele_dev_info) \
+						+ ELE_DEV_INFO_EXTRA_SZ)
+
+#define GET_SERIAL_NUM_FROM_UID(x, uid_word_sz) ({\
+	const u8 *__x = (const u8 *)(x); \
+	size_t __sz = (uid_word_sz); \
+	((u64)get_unaligned_le32(__x + (__sz - 1) * sizeof(u32)) << 32) | \
+		get_unaligned_le32(__x); \
+	})
+
+#define ELE_MAX_DBG_DMP_PKT		50
+#define ELE_DEBUG_DUMP_REQ		0x21
+#define ELE_DEBUG_DUMP_REQ_SZ		0x4
+#define ELE_DEBUG_DUMP_RSP_SZ		0x5c
+
+#define ELE_PING_REQ			0x01
+#define ELE_PING_REQ_SZ			0x04
+#define ELE_PING_RSP_SZ			0x08
+
+#define ELE_SERVICE_SWAP_REQ		0xdf
+#define ELE_SERVICE_SWAP_REQ_MSG_SZ	0x18
+#define ELE_SERVICE_SWAP_RSP_MSG_SZ	0x0c
+#define ELE_IMEM_SIZE			0x10000
+#define ELE_IMEM_STATE_OK		0xca
+#define ELE_IMEM_STATE_BAD		0xfe
+#define ELE_IMEM_STATE_WORD		0x27
+#define ELE_IMEM_STATE_MASK		0x00ff0000
+#define ELE_IMEM_EXPORT			0x1
+#define ELE_IMEM_IMPORT			0x2
+
+#define ELE_FW_AUTH_REQ			0x02
+#define ELE_FW_AUTH_REQ_SZ		0x10
+#define ELE_FW_AUTH_RSP_MSG_SZ		0x08
+
+int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info);
+int ele_fetch_soc_info(struct se_if_priv *priv, void *data);
+int ele_ping(struct se_if_priv *priv);
+int ele_service_swap(struct se_if_priv *priv, dma_addr_t addr,
+		     u32 addr_size, u16 flag);
+int ele_fw_authenticate(struct se_if_priv *priv, dma_addr_t contnr_addr,
+			dma_addr_t img_addr);
+int ele_debug_dump(struct se_if_priv *priv);
+#endif
diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
new file mode 100644
index 000000000000..bc08ea2dcd87
--- /dev/null
+++ b/drivers/firmware/imx/ele_common.c
@@ -0,0 +1,492 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2025 NXP
+ */
+
+#include "ele_base_msg.h"
+#include "ele_common.h"
+
+/*
+ * se_update_msg_chksum() - calculate and update message checksum word.
+ * @msg: message buffer.
+ * @msg_len: message length in bytes.
+ *
+ * The message length must be 4-byte aligned. The last word is treated as the
+ * checksum field and is not included in the checksum calculation.
+ *
+ * Return:
+ * 0 on success, negative errno on failure.
+ */
+int se_update_msg_chksum(u32 *msg, u32 msg_len)
+{
+	u32 nb_words;
+	u32 chksum = 0;
+	u32 i;
+
+	if (!msg)
+		return -EINVAL;
+
+	if (msg_len % SE_MSG_WORD_SZ) {
+		pr_err("Msg-len is not 4-byte aligned.\n");
+		return -EINVAL;
+	}
+
+	nb_words = msg_len / sizeof(*msg);
+	if (nb_words < 5)
+		return -EINVAL;
+
+	/* Last word is the checksum word, so skip it. */
+	nb_words--;
+
+	for (i = 0; i < nb_words; i++)
+		chksum ^= msg[i];
+
+	msg[nb_words] = chksum;
+
+	return 0;
+}
+
+int ele_msg_rcv(struct se_if_priv *priv, struct se_clbk_handle *se_clbk_hdl)
+{
+	bool is_rsp_wait_with_timeout = false;
+	bool wait_uninterruptible = false;
+	unsigned long remaining_jiffies;
+	unsigned long deadline_jiffies;
+	unsigned long flags;
+	int ret;
+
+	remaining_jiffies = msecs_to_jiffies(SE_RCV_MSG_DEFAULT_TIMEOUT_MS);
+	if (se_clbk_hdl == &priv->waiting_rsp_clbk_hdl) {
+		is_rsp_wait_with_timeout = true;
+		deadline_jiffies = jiffies + remaining_jiffies;
+	}
+
+	do {
+		if (is_rsp_wait_with_timeout) {
+			unsigned long now = jiffies;
+
+			if (time_after_eq(now, deadline_jiffies)) {
+				/* Deadline hit: fence hung FW, like the ret==0 path. */
+				spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+				se_clbk_hdl->rx_msg = NULL;
+				if (!completion_done(&se_clbk_hdl->done))
+					atomic_set(&priv->fw_busy, 1);
+				spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+				ret = -ETIMEDOUT;
+				break;
+			}
+			remaining_jiffies = deadline_jiffies - now;
+		}
+
+		if (wait_uninterruptible)
+			ret = wait_for_completion_timeout(&se_clbk_hdl->done,
+							  remaining_jiffies);
+		else
+			ret = wait_for_completion_interruptible_timeout(&se_clbk_hdl->done,
+									remaining_jiffies);
+		if (ret == -ERESTARTSYS) {
+			/*
+			 * Record that a signal was observed, then continue waiting non-
+			 * interruptibly until the response arrives or the timeout
+			 * expires. The caller can surface the interruption to userspace
+			 * after the protocol transaction is brought back to a
+			 * synchronized state.
+			 */
+			if (is_rsp_wait_with_timeout &&
+			    READ_ONCE(se_clbk_hdl->rx_msg)) {
+				WRITE_ONCE(se_clbk_hdl->signal_rcvd, true);
+				wait_uninterruptible = true;
+				continue;
+			}
+			break;
+		}
+
+		if (ret == 0) {
+			/*
+			 * The response buffer belongs to the caller of ele_msg_send_rcv()
+			 * and may be freed as soon as this function returns. Clear rx_msg
+			 * under clbk_rx_lock so that a late se_if_rx_callback() can
+			 * observe that the waiter has timed out and must not copy into
+			 * the stale buffer.
+			 *
+			 * If the completion has not yet been signaled, mark the firmware
+			 * path busy. This acts as a circuit breaker: reject new
+			 * command/response transactions until the delayed response
+			 * arrives and the callback closes the breaker.
+			 */
+
+			spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+			se_clbk_hdl->rx_msg = NULL;
+			if (!completion_done(&se_clbk_hdl->done))
+				atomic_set(&priv->fw_busy, 1);
+
+			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+			ret = -ETIMEDOUT;
+			dev_err(priv->dev,
+				"Fatal Error: SE interface %s0, hangs indefinitely.\n",
+				get_se_if_name(priv->if_defs->se_if_type));
+			break;
+		}
+		ret = se_clbk_hdl->rx_msg_sz;
+		break;
+	} while (ret < 0);
+
+	return ret;
+}
+
+int ele_msg_send(struct se_if_priv *priv,
+		 void *tx_msg,
+		 int tx_msg_sz)
+{
+	struct se_msg_hdr *header = tx_msg;
+	int err;
+
+	/*
+	 * Check that the size passed as argument matches the size
+	 * carried in the message.
+	 */
+	if (header->size << 2 != tx_msg_sz) {
+		dev_err(priv->dev,
+			"User buf hdr: 0x%x, sz mismatced with input-sz (%d != %d).",
+			*(u32 *)header, header->size << 2, tx_msg_sz);
+		return -EINVAL;
+	}
+
+	/*
+	 * The i.MX MU mailbox controller copies the payload words into MU
+	 * registers synchronously from its send path. It does not retain the
+	 * caller-provided tx_msg pointer after mbox_send_message() returns, so
+	 * the caller-owned buffer may be released after a successful send.
+	 */
+	err = mbox_send_message(priv->tx_chan, tx_msg);
+	if (err < 0) {
+		dev_err(priv->dev, "Error: mbox_send_message failure.\n");
+		return err;
+	}
+
+	return tx_msg_sz;
+}
+
+static void ele_msg_send_rcv_cleanup(struct se_if_priv *priv)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+	priv->waiting_rsp_clbk_hdl.rx_msg = NULL;
+	priv->waiting_rsp_clbk_hdl.rx_msg_sz = 0;
+	spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+}
+
+/* API used for send/receive blocking call. */
+int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
+		     void *rx_msg, int exp_rx_msg_sz)
+{
+	unsigned long flags;
+	int err;
+
+	guard(mutex)(&priv->se_if_cmd_lock);
+
+	if (atomic_read(&priv->fw_busy)) {
+		dev_dbg(priv->dev, "ELE became unresponsive.\n");
+		return -EBUSY;
+	}
+	reinit_completion(&priv->waiting_rsp_clbk_hdl.done);
+	/* Publish rx_msg/rx_msg_sz under the lock read by se_if_rx_callback(). */
+	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+	priv->waiting_rsp_clbk_hdl.rx_msg_sz = exp_rx_msg_sz;
+	priv->waiting_rsp_clbk_hdl.rx_msg = rx_msg;
+	spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+
+	err = ele_msg_send(priv, tx_msg, tx_msg_sz);
+	if (err < 0) {
+		ele_msg_send_rcv_cleanup(priv);
+		return err;
+	}
+
+	err = ele_msg_rcv(priv, &priv->waiting_rsp_clbk_hdl);
+
+	if (priv->waiting_rsp_clbk_hdl.signal_rcvd) {
+		/*
+		 * Signal was deferred until the FW/kernel protocol resynchronized.
+		 * On success report -ERESTARTSYS for the interrupted wait; the
+		 * command is not re-sent. Keep real errors like -ETIMEDOUT.
+		 */
+		if (err > 0)
+			err = -ERESTARTSYS;
+		priv->waiting_rsp_clbk_hdl.signal_rcvd = false;
+		dev_dbg(priv->dev, "Err[0x%x]:Interrupted by signal.", err);
+	}
+
+	ele_msg_send_rcv_cleanup(priv);
+
+	return err;
+}
+
+static bool check_hdr_exception_for_sz(struct se_if_priv *priv,
+				       struct se_msg_hdr *header)
+{
+	/*
+	 * List of API headers that can accept a variable length response buffer.
+	 */
+	if (header->command == ELE_DEBUG_DUMP_REQ &&
+	    header->ver == priv->if_defs->base_api_ver &&
+	    header->size >= 2 && header->size <= (ELE_DEBUG_DUMP_RSP_SZ / 4))
+		return true;
+
+	return false;
+}
+
+/*
+ * Callback called by mailbox FW, when data is received.
+ */
+void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
+{
+	struct se_clbk_handle *se_clbk_hdl;
+	struct device *dev = mbox_cl->dev;
+	struct se_msg_hdr *header;
+	bool sz_mismatch = false;
+	struct se_if_priv *priv;
+	unsigned long flags;
+	u32 rx_msg_sz;
+
+	priv = dev_get_drvdata(dev);
+	if (!priv)
+		return;
+
+	/* The function can be called with NULL msg */
+	if (IS_ERR_OR_NULL(msg)) {
+		dev_err(dev, "Message is invalid\n");
+		return;
+	}
+
+	header = msg;
+	rx_msg_sz = header->size << 2;
+
+	/* Incoming command: wake up the receiver if any. */
+	if (header->tag == priv->if_defs->cmd_tag) {
+		se_clbk_hdl = &priv->cmd_receiver_clbk_hdl;
+		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+		if (!se_clbk_hdl->rx_msg) {
+			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+			dev_warn(dev, "No command receiver registered for message: %.8x\n",
+				 *((u32 *)header));
+			return;
+		}
+
+		/*
+		 * cmd_tag messages are delivered only to the explicitly registered
+		 * command receiver. Unlike the synchronous response waiter path, the
+		 * command receiver uses a dedicated long-lived buffer installed by
+		 * SE_IOCTL_ENABLE_CMD_RCV and is not subject to the timeout/circuit-
+		 * breaker handling used for rsp_tag messages.
+		 */
+		dev_dbg(dev, "Selecting cmd receiver: for mesg header:0x%x.",
+			*(u32 *)header);
+
+		/*
+		 * Pre-allocated buffer of MAX_NVM_MSG_LEN
+		 * as the NVM command are initiated by FW.
+		 * Size is revealed as part of this call function.
+		 */
+
+		if (rx_msg_sz > MAX_NVM_MSG_LEN)
+			sz_mismatch = true;
+
+		/*
+		 * Clamp the copy length to the pre-allocated receiver buffer (MAX_NVM_MSG_LEN).
+		 */
+		se_clbk_hdl->rx_msg_sz = min_t(u32, rx_msg_sz, MAX_NVM_MSG_LEN);
+		memcpy(se_clbk_hdl->rx_msg, msg, se_clbk_hdl->rx_msg_sz);
+		complete(&se_clbk_hdl->done);
+		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+		if (sz_mismatch)
+			dev_err(dev,
+				"CMD-RCVER NVM: hdr(0x%x) with different sz(%d != %d).\n",
+				*(u32 *)header,
+				(header->size << 2), rx_msg_sz);
+	} else if (header->tag == priv->if_defs->rsp_tag) {
+		bool exception_for_sz_mismatch = check_hdr_exception_for_sz(priv, header);
+		u32 exp_rx_msg_sz = 0;
+
+		/*
+		 * rx_msg and rx_msg_sz are owned by the sender under clbk_rx_lock.
+		 * Read both under the lock: drop a late response instead of copying
+		 * into freed memory, and avoid a stale size. A late response also
+		 * closes the firmware-busy circuit breaker.
+		 */
+		se_clbk_hdl = &priv->waiting_rsp_clbk_hdl;
+		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+		if (!se_clbk_hdl->rx_msg) {
+			/* Close circuit breaker on spinlock race */
+			atomic_set(&priv->fw_busy, 0);
+			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+			dev_info(dev, "ELE responded (late), recovery FW available.");
+			return;
+		}
+		exp_rx_msg_sz = se_clbk_hdl->rx_msg_sz;
+		dev_dbg(dev, "Selecting resp waiter: for mesg header:0x%x.",
+			*(u32 *)header);
+
+		/*
+		 * For rsp_tag traffic, the sender provides the expected response
+		 * buffer size. If firmware returns a different size, clamp the copy
+		 * length to the caller's buffer capacity before memcpy() and report the
+		 * mismatch after dropping the spinlock.
+		 */
+		if (rx_msg_sz != exp_rx_msg_sz && !exception_for_sz_mismatch)
+			sz_mismatch = true;
+
+		se_clbk_hdl->rx_msg_sz = min(rx_msg_sz, exp_rx_msg_sz);
+		memcpy(se_clbk_hdl->rx_msg, msg, se_clbk_hdl->rx_msg_sz);
+		complete(&se_clbk_hdl->done);
+		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+
+		if (sz_mismatch)
+			dev_err(dev,
+				"Rsp to CMD: hdr(0x%x) with different sz(%d != %d).\n",
+				*(u32 *)header,
+				(header->size << 2), exp_rx_msg_sz);
+	} else {
+		dev_err(dev, "Failed to select a device for message: %.8x\n",
+			*((u32 *)header));
+	}
+}
+
+int se_val_rsp_hdr_n_status(struct se_if_priv *priv, struct se_api_msg *msg,
+			    u8 msg_id, u8 sz, bool is_base_api)
+{
+	struct se_msg_hdr *header = &msg->header;
+	u32 status;
+
+	if (header->tag != priv->if_defs->rsp_tag) {
+		dev_dbg(priv->dev, "MSG[0x%x] Hdr: Resp tag mismatch. (0x%x != 0x%x)",
+			msg_id, header->tag, priv->if_defs->rsp_tag);
+		return -EINVAL;
+	}
+
+	if (header->command != msg_id) {
+		dev_dbg(priv->dev, "MSG Header: Cmd id mismatch. (0x%x != 0x%x)",
+			header->command, msg_id);
+		return -EINVAL;
+	}
+
+	if ((sz % 4) || (header->size != (sz >> 2) &&
+			 !check_hdr_exception_for_sz(priv, header))) {
+		dev_dbg(priv->dev, "MSG[0x%x] Hdr: Cmd size mismatch. (0x%x != 0x%x)",
+			msg_id, header->size, (sz >> 2));
+		return -EINVAL;
+	}
+
+	if (is_base_api && header->ver != priv->if_defs->base_api_ver) {
+		dev_dbg(priv->dev,
+			"MSG[0x%x] Hdr: Base API Vers mismatch. (0x%x != 0x%x)",
+			msg_id, header->ver, priv->if_defs->base_api_ver);
+		return -EINVAL;
+	} else if (!is_base_api && header->ver != priv->if_defs->fw_api_ver) {
+		dev_dbg(priv->dev,
+			"MSG[0x%x] Hdr: FW API Vers mismatch. (0x%x != 0x%x)",
+			msg_id, header->ver, priv->if_defs->fw_api_ver);
+		return -EINVAL;
+	}
+
+	if (header->size > SE_MU_HDR_WORD_SZ) {
+		status = RES_STATUS(msg->data[0]);
+		if (status != priv->if_defs->success_tag) {
+			dev_dbg(priv->dev, "Command Id[%x], Response Failure = 0x%x",
+				header->command, status);
+			return -EPERM;
+		}
+	}
+
+	return 0;
+}
+
+int se_save_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem)
+{
+	struct ele_dev_info s_info = {0};
+	int ret;
+
+	ret = ele_get_info(priv, &s_info);
+	if (ret) {
+		dev_err(priv->dev, "Failed to get info from ELE.\n");
+		return ret;
+	}
+
+	/* Check for the imem-state before continue to save imem state. */
+	if (s_info.d_addn_info.imem_state == ELE_IMEM_STATE_BAD)
+		return 0;
+
+	/*
+	 * EXPORT command will save encrypted IMEM to given address,
+	 * so later in resume, IMEM can be restored from the given
+	 * address.
+	 *
+	 * Size must be at least 64 kB.
+	 */
+	ret = ele_service_swap(priv, imem->daddr, ELE_IMEM_SIZE, ELE_IMEM_EXPORT);
+	if (ret < 0) {
+		dev_err(priv->dev, "Failed to export IMEM.");
+		imem->size = 0;
+	} else if (ret > ELE_IMEM_SIZE) {
+		dev_err(priv->dev, "Invalid exported IMEM size %d.", ret);
+		imem->size = 0;
+		ret = -EIO;
+	} else {
+		dev_dbg(priv->dev,
+			"Exported %d bytes of encrypted IMEM.",
+			ret);
+		imem->size = ret;
+	}
+
+	return ret > 0 ? 0 : ret;
+}
+
+int se_restore_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem)
+{
+	struct ele_dev_info s_info;
+	int ret;
+
+	/* get info from ELE */
+	ret = ele_get_info(priv, &s_info);
+	if (ret) {
+		dev_err(priv->dev, "Failed to get info from ELE.");
+		return ret;
+	}
+	imem->state = s_info.d_addn_info.imem_state;
+
+	/* Check for the imem-state and imem-size before continue to
+	 * restore imem state.
+	 */
+	if (s_info.d_addn_info.imem_state != ELE_IMEM_STATE_BAD || !imem->size)
+		return 0;
+
+	/*
+	 * IMPORT command will restore IMEM from the given
+	 * address, here size is the actual size returned by ELE
+	 * during the export operation
+	 */
+	ret = ele_service_swap(priv, imem->daddr, imem->size, ELE_IMEM_IMPORT);
+	if (ret) {
+		dev_err(priv->dev, "Failed to import IMEM");
+		return ret;
+	}
+
+	/*
+	 * After importing IMEM, check if IMEM state is equal to 0xCA
+	 * to ensure IMEM is fully loaded and
+	 * ELE functionality can be used.
+	 */
+	ret = ele_get_info(priv, &s_info);
+	if (ret) {
+		dev_err(priv->dev, "Failed to get info from ELE.");
+		return ret;
+	}
+	imem->state = s_info.d_addn_info.imem_state;
+
+	if (s_info.d_addn_info.imem_state == ELE_IMEM_STATE_OK)
+		dev_dbg(priv->dev, "Successfully restored IMEM.");
+	else
+		dev_err(priv->dev, "Failed to restore IMEM.");
+
+	return ret;
+}
diff --git a/drivers/firmware/imx/ele_common.h b/drivers/firmware/imx/ele_common.h
new file mode 100644
index 000000000000..7bf2febefc45
--- /dev/null
+++ b/drivers/firmware/imx/ele_common.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2025 NXP
+ */
+
+#ifndef __ELE_COMMON_H__
+#define __ELE_COMMON_H__
+
+#include "se_ctrl.h"
+
+#define SE_RCV_MSG_DEFAULT_TIMEOUT_MS	3000
+
+#define ELE_SUCCESS_IND			0xD6
+
+#define IMX_ELE_FW_DIR                 "imx/ele/"
+
+int se_update_msg_chksum(u32 *msg, u32 msg_len);
+
+int ele_msg_rcv(struct se_if_priv *priv, struct se_clbk_handle *se_clbk_hdl);
+
+int ele_msg_send(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz);
+
+int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
+		     void *rx_msg, int exp_rx_msg_sz);
+
+void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg);
+
+int se_val_rsp_hdr_n_status(struct se_if_priv *priv, struct se_api_msg *msg,
+			    u8 msg_id, u8 sz, bool is_base_api);
+
+/* Fill a command message header with a given command ID and length in bytes. */
+static inline void se_fill_cmd_msg_hdr(struct se_if_priv *priv, struct se_msg_hdr *hdr,
+				       u8 cmd, u32 len, bool is_base_api)
+{
+	hdr->tag = priv->if_defs->cmd_tag;
+	hdr->ver = (is_base_api) ? priv->if_defs->base_api_ver : priv->if_defs->fw_api_ver;
+	hdr->command = cmd;
+	hdr->size = len >> 2;
+}
+
+int se_save_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem);
+
+int se_restore_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem);
+
+#endif /*__ELE_COMMON_H__ */
diff --git a/drivers/firmware/imx/se_ctrl.c b/drivers/firmware/imx/se_ctrl.c
new file mode 100644
index 000000000000..53091cc37e7e
--- /dev/null
+++ b/drivers/firmware/imx/se_ctrl.c
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2026 NXP
+ */
+
+#include <linux/bitfield.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/firmware.h>
+#include <linux/firmware/imx/se_api.h>
+#include <linux/genalloc.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sys_soc.h>
+
+#include "ele_base_msg.h"
+#include "ele_common.h"
+#include "se_ctrl.h"
+
+#define MAX_SOC_INFO_DATA_SZ		256
+#define MBOX_TX_NAME			"tx"
+#define MBOX_RX_NAME			"rx"
+
+#define SE_TYPE_STR_DBG			"dbg"
+#define SE_TYPE_STR_HSM			"hsm"
+
+#define SE_TYPE_ID_DBG			0x1
+
+#define SE_TYPE_ID_HSM			0x2
+
+struct se_soc_dev_regn {
+	bool soc_dev_registered;
+	struct soc_device *soc_dev;
+	struct soc_device_attribute *soc_dev_attr;
+};
+
+struct se_var_info {
+	u16 soc_rev;
+	struct se_soc_dev_regn soc_dev_regn;
+	/* To serialize populating common SoC level info. */
+	struct mutex se_var_info_lock;
+};
+
+/* contains fixed information */
+struct se_soc_info {
+	const u16 soc_id;
+	const char *soc_name;
+	const struct se_fw_img_name se_fw_img_nm;
+	bool imem_state_mgmt;
+};
+
+struct se_if_node {
+	struct se_soc_info *se_info;
+	u8 *pool_name;
+	bool reserved_dma_ranges;
+	struct se_if_defines if_defs;
+};
+
+/* common for all the SoC. */
+static struct se_var_info var_se_info = {
+	.soc_rev = 0,
+	.se_var_info_lock = __MUTEX_INITIALIZER(var_se_info.se_var_info_lock)
+};
+
+static struct se_soc_info se_imx8ulp_info = {
+	.soc_id = SOC_ID_OF_IMX8ULP,
+	.soc_name = "i.MX8ULP",
+	.se_fw_img_nm = {
+		.prim_fw_nm_in_rfs = IMX_ELE_FW_DIR
+			"mx8ulpa2-ahab-container.img",
+		.seco_fw_nm_in_rfs = IMX_ELE_FW_DIR
+			"mx8ulpa2ext-ahab-container.img",
+	},
+	.imem_state_mgmt = true,
+};
+
+static struct se_if_node imx8ulp_se_ele_hsm = {
+	.se_info = &se_imx8ulp_info,
+	.pool_name = "sram",
+	.reserved_dma_ranges = true,
+	.if_defs = {
+		.se_if_type = SE_TYPE_ID_HSM,
+		.cmd_tag = 0x17,
+		.rsp_tag = 0xe1,
+		.success_tag = ELE_SUCCESS_IND,
+		.base_api_ver = MESSAGING_VERSION_6,
+		.fw_api_ver = MESSAGING_VERSION_7,
+	},
+};
+
+static struct se_soc_info se_imx93_info = {
+	.soc_id = SOC_ID_OF_IMX93,
+};
+
+static struct se_if_node imx93_se_ele_hsm = {
+	.se_info = &se_imx93_info,
+	.reserved_dma_ranges = true,
+	.if_defs = {
+		.se_if_type = SE_TYPE_ID_HSM,
+		.cmd_tag = 0x17,
+		.rsp_tag = 0xe1,
+		.success_tag = ELE_SUCCESS_IND,
+		.base_api_ver = MESSAGING_VERSION_6,
+		.fw_api_ver = MESSAGING_VERSION_7,
+	},
+};
+
+static const struct of_device_id se_match[] = {
+	{ .compatible = "fsl,imx8ulp-se-ele-hsm", .data = &imx8ulp_se_ele_hsm },
+	{ .compatible = "fsl,imx93-se-ele-hsm", .data = &imx93_se_ele_hsm },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, se_match);
+
+char *get_se_if_name(u8 se_if_id)
+{
+	switch (se_if_id) {
+	case SE_TYPE_ID_DBG: return SE_TYPE_STR_DBG;
+	case SE_TYPE_ID_HSM: return SE_TYPE_STR_HSM;
+	}
+
+	return "unknown";
+}
+
+static struct se_fw_load_info *get_load_fw_instance(struct se_if_priv *priv)
+{
+	return &priv->load_fw;
+}
+
+static void se_soc_device_unregister(struct se_soc_dev_regn *soc_dev_regn)
+{
+	guard(mutex)(&var_se_info.se_var_info_lock);
+
+	if (soc_dev_regn->soc_dev) {
+		soc_device_unregister(soc_dev_regn->soc_dev);
+		soc_dev_regn->soc_dev = NULL;
+	}
+
+	if (soc_dev_regn->soc_dev_attr) {
+		/*
+		 * revision and serial_number are the only kasprintf()-allocated
+		 * strings. machine points into the DT, and soc_id/family are
+		 * constants, so they must not be freed.
+		 */
+		kfree(soc_dev_regn->soc_dev_attr->revision);
+		kfree(soc_dev_regn->soc_dev_attr->serial_number);
+		kfree(soc_dev_regn->soc_dev_attr);
+		soc_dev_regn->soc_dev_attr = NULL;
+	}
+
+	soc_dev_regn->soc_dev_registered = false;
+}
+
+/*
+ * Build and register a soc_device entry for this SoC. Separated from
+ * get_se_soc_info() so that the firmware-fetch path and the sysfs
+ * registration path can be reasoned about independently.
+ */
+static int se_soc_dev_register(struct se_if_priv *priv, u16 soc_rev,
+			       const char *soc_name, const u8 *uid)
+{
+	struct soc_device_attribute *attr;
+	struct soc_device *sdev;
+	int err;
+
+	if (!soc_rev || !soc_name || !uid)
+		return -EINVAL;
+
+	attr = kzalloc_obj(*attr, GFP_KERNEL);
+	if (!attr)
+		return -ENOMEM;
+
+	if (FIELD_GET(DEV_GETINFO_MIN_VER_MASK, soc_rev))
+		attr->revision = kasprintf(GFP_KERNEL, "%x.%x",
+					   FIELD_GET(DEV_GETINFO_MAJ_VER_MASK, soc_rev),
+					   FIELD_GET(DEV_GETINFO_MIN_VER_MASK, soc_rev));
+	else
+		attr->revision = kasprintf(GFP_KERNEL, "%x",
+					   FIELD_GET(DEV_GETINFO_MAJ_VER_MASK, soc_rev));
+
+	if (!attr->revision) {
+		err = -ENOMEM;
+		goto err_free_attr;
+	}
+
+	attr->soc_id = soc_name;
+
+	err = of_property_read_string(of_root, "model", &attr->machine);
+	if (err) {
+		err = -EINVAL;
+		goto err_free_rev;
+	}
+
+	attr->family = "Freescale i.MX";
+
+	attr->serial_number = kasprintf(GFP_KERNEL, "%016llX",
+					GET_SERIAL_NUM_FROM_UID(uid, MAX_UID_SIZE >> 2));
+	if (!attr->serial_number) {
+		err = -ENOMEM;
+		goto err_free_rev;
+	}
+
+	sdev = soc_device_register(attr);
+	if (IS_ERR(sdev)) {
+		err = PTR_ERR(sdev);
+		goto err_free_serial;
+	}
+
+	/*
+	 * Publish the singleton. Freed once, at module unload, by
+	 * se_soc_device_unregister(). Caller holds se_var_info_lock.
+	 */
+	var_se_info.soc_dev_regn.soc_dev = sdev;
+	var_se_info.soc_dev_regn.soc_dev_attr = attr;
+
+	/* Mark registration complete so get_se_soc_info() skips this path on retry. */
+	var_se_info.soc_dev_regn.soc_dev_registered = true;
+
+	return 0;
+
+err_free_serial:
+	kfree(attr->serial_number);
+err_free_rev:
+	kfree(attr->revision);
+err_free_attr:
+	kfree(attr);
+
+	return err;
+}
+
+static int get_se_soc_info(struct se_if_priv *priv, const struct se_soc_info *se_info)
+{
+	struct se_fw_load_info *load_fw = get_load_fw_instance(priv);
+	u8 data[MAX_SOC_INFO_DATA_SZ];
+	struct ele_dev_info *s_info;
+	int err;
+
+	guard(mutex)(&var_se_info.se_var_info_lock);
+
+	/*
+	 * Early exit: both objectives already complete, nothing to do.
+	 */
+	if (var_se_info.soc_rev &&
+	    (!se_info->soc_name || var_se_info.soc_dev_regn.soc_dev_registered))
+		return 0;
+
+	err = ele_fetch_soc_info(priv, &data);
+	if (err < 0)
+		return dev_err_probe(priv->dev, err, "Failed to fetch SoC Info.");
+
+	s_info = (struct ele_dev_info *)data;
+
+	if (!var_se_info.soc_rev) {
+		var_se_info.soc_rev = s_info->d_info.soc_rev;
+
+		/*
+		 * Only update IMEM state when the load_fw path is active;
+		 * on SoCs without IMEM management (e.g. i.MX93) the field
+		 * is not meaningful.
+		 */
+		if (load_fw->imem_mgmt)
+			load_fw->imem.state = s_info->d_addn_info.imem_state;
+	}
+
+	if (se_info->soc_name && !var_se_info.soc_dev_regn.soc_dev_registered) {
+		err = se_soc_dev_register(priv, var_se_info.soc_rev,
+					  se_info->soc_name, s_info->d_info.uid);
+		if (err < 0)
+			return dev_err_probe(priv->dev, err,
+					     "Failed to register SE SoC device.");
+	}
+
+	return 0;
+}
+
+static int se_if_request_channel(struct device *dev, struct mbox_chan **chan,
+				 struct mbox_client *cl, const char *name)
+{
+	struct mbox_chan *t_chan;
+
+	t_chan = mbox_request_channel_byname(cl, name);
+	if (IS_ERR(t_chan))
+		return dev_err_probe(dev, PTR_ERR(t_chan),
+				     "Failed to request %s channel.", name);
+
+	*chan = t_chan;
+
+	return 0;
+}
+
+static void se_if_probe_cleanup(void *plat_dev)
+{
+	struct platform_device *pdev = plat_dev;
+	struct device *dev = &pdev->dev;
+	struct se_if_priv *priv;
+
+	priv = dev_get_drvdata(dev);
+	if (!priv)
+		return;
+
+	if (priv->rx_chan)
+		mbox_free_channel(priv->rx_chan);
+	if (priv->tx_chan)
+		mbox_free_channel(priv->tx_chan);
+
+	/*
+	 * Being device managed buffer, no need to free the buffer allocated
+	 * in se probe to store encrypted IMEM.
+	 */
+
+	/*
+	 * No need to check, if reserved memory is allocated
+	 * before calling for its release. Or clearing the
+	 * un-set bit.
+	 */
+	of_reserved_mem_device_release(dev);
+
+	dev_set_drvdata(dev, NULL);
+
+	kfree(priv);
+}
+
+static int se_if_probe(struct platform_device *pdev)
+{
+	const struct se_soc_info *se_info;
+	const struct se_if_node *if_node;
+	struct se_fw_load_info *load_fw;
+	struct device *dev = &pdev->dev;
+	struct se_if_priv *priv;
+	int ret;
+
+	if_node = device_get_match_data(dev);
+	if (!if_node)
+		return -EINVAL;
+
+	se_info = if_node->se_info;
+
+	priv = kzalloc_obj(*priv, GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+	priv->if_defs = &if_node->if_defs;
+	dev_set_drvdata(dev, priv);
+
+	mutex_init(&priv->se_if_cmd_lock);
+	spin_lock_init(&priv->cmd_receiver_clbk_hdl.clbk_rx_lock);
+	spin_lock_init(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock);
+	atomic_set(&priv->fw_busy, 0);
+	init_completion(&priv->waiting_rsp_clbk_hdl.done);
+	init_completion(&priv->cmd_receiver_clbk_hdl.done);
+
+	ret = devm_add_action_or_reset(dev, se_if_probe_cleanup, pdev);
+	if (ret)
+		return ret;
+
+	/* Mailbox client configuration */
+	priv->se_mb_cl.dev		= dev;
+	priv->se_mb_cl.tx_block		= false;
+	priv->se_mb_cl.knows_txdone	= false;
+	priv->se_mb_cl.rx_callback	= se_if_rx_callback;
+
+	ret = se_if_request_channel(dev, &priv->tx_chan, &priv->se_mb_cl, MBOX_TX_NAME);
+	if (ret)
+		return ret;
+
+	ret = se_if_request_channel(dev, &priv->rx_chan, &priv->se_mb_cl, MBOX_RX_NAME);
+	if (ret)
+		return ret;
+
+	if (if_node->pool_name) {
+		priv->mem_pool = of_gen_pool_get(dev->of_node, if_node->pool_name, 0);
+		if (!priv->mem_pool)
+			return dev_err_probe(dev, -ENOMEM,
+					     "Unable to get sram pool = %s.",
+					     if_node->pool_name);
+	}
+
+	if (if_node->reserved_dma_ranges) {
+		ret = of_reserved_mem_device_init(dev);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					    "Failed to init reserved memory region.");
+	}
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to set 32-bit coherent DMA mask.");
+
+	/*
+	 * Initialize load_fw_lock before registering the misc device.
+	 * A userspace process could open the device and trigger se_load_firmware()
+	 * via IOCTL immediately after misc_register(), so the mutex must be ready
+	 * before the device becomes visible.
+	 */
+	if (se_info->se_fw_img_nm.seco_fw_nm_in_rfs) {
+		load_fw = get_load_fw_instance(priv);
+		mutex_init(&load_fw->load_fw_lock);
+		load_fw->se_fw_img_nm = &se_info->se_fw_img_nm;
+		load_fw->is_fw_tobe_loaded = true;
+	}
+
+	/* By default, there is no pending FW to be loaded.*/
+	if (se_info->imem_state_mgmt) {
+		load_fw = get_load_fw_instance(priv);
+
+		/* allocate buffer where SE store encrypted IMEM */
+		load_fw->imem.buf = dmam_alloc_coherent(priv->dev, ELE_IMEM_SIZE,
+							&load_fw->imem.daddr,
+							GFP_KERNEL);
+		if (!load_fw->imem.buf)
+			return dev_err_probe(dev, -ENOMEM,
+					     "dmam-alloc-failed: To store encr-IMEM.");
+		load_fw->imem_mgmt = true;
+	}
+
+	if (if_node->if_defs.se_if_type == SE_TYPE_ID_HSM) {
+		ret = get_se_soc_info(priv, se_info);
+		if (ret)
+			return dev_err_probe(dev, ret, "Failed to fetch SoC Info.");
+	}
+
+	dev_info(dev, "i.MX secure-enclave: %s0 interface to firmware, configured.",
+		 get_se_if_name(priv->if_defs->se_if_type));
+
+	return ret;
+}
+
+static int se_suspend(struct device *dev)
+{
+	struct se_if_priv *priv = dev_get_drvdata(dev);
+	struct se_fw_load_info *load_fw;
+	int ret = 0;
+
+	load_fw = get_load_fw_instance(priv);
+
+	if (load_fw->imem_mgmt) {
+		ret = se_save_imem_state(priv, &load_fw->imem);
+		if (ret)
+			dev_warn(dev, "Failure saving IMEM state[0x%x]", ret);
+	}
+
+	return 0;
+}
+
+static int se_resume(struct device *dev)
+{
+	struct se_if_priv *priv = dev_get_drvdata(dev);
+	struct se_fw_load_info *load_fw;
+	int ret = 0;
+
+	load_fw = get_load_fw_instance(priv);
+
+	if (load_fw->imem_mgmt) {
+		ret = se_restore_imem_state(priv, &load_fw->imem);
+		if (ret)
+			dev_warn(dev, "Failure restoring IMEM state[0x%x]", ret);
+	}
+
+	return 0;
+}
+
+DEFINE_SIMPLE_DEV_PM_OPS(se_pm, se_suspend, se_resume);
+
+static struct platform_driver se_driver = {
+	.driver = {
+		.name = "fsl-se",
+		.of_match_table = se_match,
+		.pm = pm_sleep_ptr(&se_pm),
+	},
+	.probe = se_if_probe,
+};
+
+static int __init se_init(void)
+{
+	return platform_driver_register(&se_driver);
+}
+module_init(se_init);
+
+static void __exit se_exit(void)
+{
+	platform_driver_unregister(&se_driver);
+
+	/*
+	 * The soc_device is a module-scoped singleton that outlives any single
+	 * MU interface bind/unbind. Release it here, once, after every interface
+	 * has been unbound, so its lifetime is tied to the module rather than to
+	 * the first-probed interface.
+	 */
+	se_soc_device_unregister(&var_se_info.soc_dev_regn);
+}
+module_exit(se_exit);
+
+MODULE_AUTHOR("Pankaj Gupta <pankaj.gupta@nxp.com>");
+MODULE_DESCRIPTION("iMX Secure Enclave Driver.");
+MODULE_LICENSE("GPL");
diff --git a/drivers/firmware/imx/se_ctrl.h b/drivers/firmware/imx/se_ctrl.h
new file mode 100644
index 000000000000..54b2a262a2c3
--- /dev/null
+++ b/drivers/firmware/imx/se_ctrl.h
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2026 NXP
+ */
+
+#ifndef SE_CTRL_H
+#define SE_CTRL_H
+
+#include <linux/bitfield.h>
+#include <linux/miscdevice.h>
+#include <linux/mailbox_client.h>
+#include <linux/semaphore.h>
+
+#define MAX_FW_LOAD_RETRIES		50
+#define SE_MSG_WORD_SZ			0x4
+
+#define RES_STATUS(x)			FIELD_GET(0x000000ff, x)
+#define MAX_NVM_MSG_LEN			(256)
+#define MESSAGING_VERSION_6		0x6
+#define MESSAGING_VERSION_7		0x7
+
+struct se_clbk_handle {
+	struct completion done;
+	bool signal_rcvd;
+	u32 rx_msg_sz;
+	/*
+	 * Assignment of the rx_msg buffer to held till the
+	 * received content as part callback function, is copied.
+	 */
+	struct se_api_msg *rx_msg;
+	/*
+	 * Serialise the timeout path in ele_msg_rcv() against
+	 * se_if_rx_callback() so that the callback can never
+	 * memcpy into a buffer that the timeout path has already
+	 * freed.
+	 */
+	spinlock_t clbk_rx_lock;
+};
+
+struct se_imem_buf {
+	u8 *buf;
+	dma_addr_t daddr;
+	u32 size;
+	u32 state;
+};
+
+/* Header of the messages exchange with the EdgeLock Enclave */
+struct se_msg_hdr {
+	u8 ver;
+	u8 size;
+	u8 command;
+	u8 tag;
+}  __packed;
+
+#define SE_MU_HDR_SZ		4
+#define SE_MU_HDR_WORD_SZ	1
+
+struct se_api_msg {
+	struct se_msg_hdr header;
+	u32 data[];
+};
+
+struct se_if_defines {
+	const u8 se_if_type;
+	u8 cmd_tag;
+	u8 rsp_tag;
+	u8 success_tag;
+	u8 base_api_ver;
+	u8 fw_api_ver;
+};
+
+struct se_fw_img_name {
+	const char *prim_fw_nm_in_rfs;
+	const char *seco_fw_nm_in_rfs;
+};
+
+struct se_fw_load_info {
+	const struct se_fw_img_name *se_fw_img_nm;
+	bool is_fw_tobe_loaded;
+	bool imem_mgmt;
+	struct se_imem_buf imem;
+	/* to serialize the fw load state */
+	struct mutex load_fw_lock;
+};
+
+struct se_if_priv {
+	struct device *dev;
+
+	struct se_clbk_handle cmd_receiver_clbk_hdl;
+	/*
+	 * Update to the waiting_rsp_dev, to be protected
+	 * under se_if_cmd_lock.
+	 */
+	struct se_clbk_handle waiting_rsp_clbk_hdl;
+	/*
+	 * prevent new command to be sent on the se interface while previous
+	 * command is still processing. (response is awaited)
+	 */
+	struct mutex se_if_cmd_lock;
+
+	struct mbox_client se_mb_cl;
+	struct mbox_chan *tx_chan, *rx_chan;
+
+	struct gen_pool *mem_pool;
+	const struct se_if_defines *if_defs;
+	struct se_fw_load_info load_fw;
+
+	atomic_t fw_busy;
+};
+
+char *get_se_if_name(u8 se_if_id);
+#endif
diff --git a/include/linux/firmware/imx/se_api.h b/include/linux/firmware/imx/se_api.h
new file mode 100644
index 000000000000..b1c4c9115d7b
--- /dev/null
+++ b/include/linux/firmware/imx/se_api.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2025 NXP
+ */
+
+#ifndef __SE_API_H__
+#define __SE_API_H__
+
+#include <linux/types.h>
+
+#define SOC_ID_OF_IMX8ULP		0x084d
+#define SOC_ID_OF_IMX93			0x9300
+
+#endif /* __SE_API_H__ */

-- 
2.43.0

Re: [PATCH v34 3/7] firmware: imx: add driver for NXP EdgeLock Enclave

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Critical] The DMA buffer passed to the enclave firmware is freed unconditionally on timeout, creating a window where delayed firmware operations will corrupt memory.
- [Medium] The core messaging function `ele_msg_send_rcv` incorrectly returns `-ERESTARTSYS` when a firmware command completes successfully, but a signal was received during the wait. This causes non-idempotent operations to be incorrectly reported as interrupted and potentially re-executed.
--

--- Patch [3]: [PATCH v34 3/7] firmware: imx: add driver for NXP EdgeLock Enclave ---
commit 33c1a4b0c7dcc5a0ad9f6bb5fbdd591b9371ef2d
Author: Pankaj Gupta <pankaj.gupta@nxp.com>
Subject: firmware: imx: add driver for NXP EdgeLock Enclave

Add MU-based communication interface for secure enclave. The secure enclave
FW communicates with Linux over single or multiple dedicated messaging
unit(MU) based interface(s). Exists on i.MX SoC(s) like i.MX8ULP, i.MX93,
i.MX95 etc.

Closes: https://sashiko.dev/#/patchset/20260121-imx-se-if-v32-0-c5222df51cc2@nxp.com?part=3

> diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
> index 0000000000000..724f6e913ce79
> --- /dev/null
> +++ b/drivers/firmware/imx/ele_base_msg.c

[ ... ]

> +static void ele_get_info_cleanup(struct se_if_priv *priv, u32 *buf, dma_addr_t d_addr,
> +				 size_t size)
> +{
> +	if (priv->mem_pool)
> +		gen_pool_free(priv->mem_pool, (unsigned long)buf, size);
> +	else
> +		dma_free_coherent(priv->dev, size, buf, d_addr);
> +}
> +
> +int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
> +{

[ ... ]

> +	ret = ele_msg_send_rcv(priv, tx_msg, ELE_GET_INFO_REQ_MSG_SZ, rx_msg,
> +			       ELE_GET_INFO_RSP_MSG_SZ);
> +	if (ret < 0) {
> +		ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);

[Severity: Critical]
If ele_msg_send_rcv() times out and returns -ETIMEDOUT, does this unconditionally
free the DMA buffer while the firmware might still be active?

If the firmware is merely slow and responds after the timeout, it could write
up to 160 bytes into this physical memory after it has been returned to the
page allocator or gen_pool, potentially causing memory corruption. 

Should we avoid freeing this buffer if the firmware transaction has not been safely
aborted?

> +		return ret;
> +	}

> diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
> index 0000000000000..bc08ea2dcd87d
> --- /dev/null
> +++ b/drivers/firmware/imx/ele_common.c

[ ... ]

> +int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
> +		     void *rx_msg, int exp_rx_msg_sz)
> +{

[ ... ]

> +	if (priv->waiting_rsp_clbk_hdl.signal_rcvd) {
> +		/*
> +		 * Signal was deferred until the FW/kernel protocol resynchronized.
> +		 * On success report -ERESTARTSYS for the interrupted wait; the
> +		 * command is not re-sent. Keep real errors like -ETIMEDOUT.
> +		 */
> +		if (err > 0)
> +			err = -ERESTARTSYS;

[Severity: Medium]
If a signal is received but the firmware successfully completes the command
(err > 0), replacing the result with -ERESTARTSYS discards the hardware
response data. 

Could this cause issues if the operation is exposed to userspace later? The
VFS would restart the syscall and re-execute the firmware operation, which
might not be idempotent. 

Is it intentional to discard a successful response here?

> +		priv->waiting_rsp_clbk_hdl.signal_rcvd = false;
> +		dev_dbg(priv->dev, "Err[0x%x]:Interrupted by signal.", err);
> +	}
> +
> +	ele_msg_send_rcv_cleanup(priv);
> +
> +	return err;
> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-imx-se-if-v34-0-7e4713d14e0a@nxp.com?part=3

[PATCH v34 4/7] firmware: imx: device context dedicated to priv

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Add priv_dev_ctx to prepare enabling misc-device context based send-receive
path, to communicate with FW.

No functionality change.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/firmware/imx/ele_base_msg.c | 15 +++++-----
 drivers/firmware/imx/ele_common.c   | 55 +++++++++++++++++++++----------------
 drivers/firmware/imx/ele_common.h   |  8 +++---
 drivers/firmware/imx/se_ctrl.c      | 41 +++++++++++++++++++++++++++
 drivers/firmware/imx/se_ctrl.h      |  9 ++++++
 5 files changed, 94 insertions(+), 34 deletions(-)

diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
index 724f6e913ce7..b70e3ef88a16 100644
--- a/drivers/firmware/imx/ele_base_msg.c
+++ b/drivers/firmware/imx/ele_base_msg.c
@@ -71,8 +71,9 @@ int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
 	tx_msg->data[0] = upper_32_bits(get_info_addr);
 	tx_msg->data[1] = lower_32_bits(get_info_addr);
 	tx_msg->data[2] = sizeof(*s_info);
-	ret = ele_msg_send_rcv(priv, tx_msg, ELE_GET_INFO_REQ_MSG_SZ, rx_msg,
-			       ELE_GET_INFO_RSP_MSG_SZ);
+
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_GET_INFO_REQ_MSG_SZ,
+			       rx_msg, ELE_GET_INFO_RSP_MSG_SZ);
 	if (ret < 0) {
 		ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);
 		return ret;
@@ -117,8 +118,8 @@ int ele_ping(struct se_if_priv *priv)
 	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
 			    ELE_PING_REQ, ELE_PING_REQ_SZ, true);
 
-	ret = ele_msg_send_rcv(priv, tx_msg, ELE_PING_REQ_SZ, rx_msg,
-			       ELE_PING_RSP_SZ);
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_PING_REQ_SZ,
+			       rx_msg, ELE_PING_RSP_SZ);
 	if (ret < 0)
 		return ret;
 
@@ -165,7 +166,7 @@ int ele_service_swap(struct se_if_priv *priv,
 	if (ret)
 		return -EINVAL;
 
-	ret = ele_msg_send_rcv(priv, tx_msg, ELE_SERVICE_SWAP_REQ_MSG_SZ,
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_SERVICE_SWAP_REQ_MSG_SZ,
 			       rx_msg, ELE_SERVICE_SWAP_RSP_MSG_SZ);
 	if (ret < 0)
 		return ret;
@@ -213,7 +214,7 @@ int ele_fw_authenticate(struct se_if_priv *priv, dma_addr_t contnr_addr,
 	tx_msg->data[1] = 0;
 	tx_msg->data[2] = lower_32_bits(img_addr);
 
-	ret = ele_msg_send_rcv(priv, tx_msg, ELE_FW_AUTH_REQ_SZ, rx_msg,
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_FW_AUTH_REQ_SZ, rx_msg,
 			       ELE_FW_AUTH_RSP_MSG_SZ);
 	if (ret < 0)
 		return ret;
@@ -251,7 +252,7 @@ int ele_debug_dump(struct se_if_priv *priv)
 	do {
 		memset(rx_msg, 0x0, ELE_DEBUG_DUMP_RSP_SZ);
 
-		ret = ele_msg_send_rcv(priv, tx_msg, ELE_DEBUG_DUMP_REQ_SZ,
+		ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_DEBUG_DUMP_REQ_SZ,
 				       rx_msg, ELE_DEBUG_DUMP_RSP_SZ);
 		if (ret < 0)
 			return ret;
diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
index bc08ea2dcd87..707fb69431ba 100644
--- a/drivers/firmware/imx/ele_common.c
+++ b/drivers/firmware/imx/ele_common.c
@@ -46,8 +46,9 @@ int se_update_msg_chksum(u32 *msg, u32 msg_len)
 	return 0;
 }
 
-int ele_msg_rcv(struct se_if_priv *priv, struct se_clbk_handle *se_clbk_hdl)
+int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk_hdl)
 {
+	struct se_if_priv *priv = dev_ctx->priv;
 	bool is_rsp_wait_with_timeout = false;
 	bool wait_uninterruptible = false;
 	unsigned long remaining_jiffies;
@@ -134,7 +135,7 @@ int ele_msg_rcv(struct se_if_priv *priv, struct se_clbk_handle *se_clbk_hdl)
 	return ret;
 }
 
-int ele_msg_send(struct se_if_priv *priv,
+int ele_msg_send(struct se_if_device_ctx *dev_ctx,
 		 void *tx_msg,
 		 int tx_msg_sz)
 {
@@ -146,9 +147,9 @@ int ele_msg_send(struct se_if_priv *priv,
 	 * carried in the message.
 	 */
 	if (header->size << 2 != tx_msg_sz) {
-		dev_err(priv->dev,
-			"User buf hdr: 0x%x, sz mismatced with input-sz (%d != %d).",
-			*(u32 *)header, header->size << 2, tx_msg_sz);
+		dev_err(dev_ctx->priv->dev,
+			"%s: User buf hdr: 0x%x, sz mismatched with input-sz (%d != %d).",
+			dev_ctx->devname, *(u32 *)header, header->size << 2, tx_msg_sz);
 		return -EINVAL;
 	}
 
@@ -158,9 +159,10 @@ int ele_msg_send(struct se_if_priv *priv,
 	 * caller-provided tx_msg pointer after mbox_send_message() returns, so
 	 * the caller-owned buffer may be released after a successful send.
 	 */
-	err = mbox_send_message(priv->tx_chan, tx_msg);
+	err = mbox_send_message(dev_ctx->priv->tx_chan, tx_msg);
 	if (err < 0) {
-		dev_err(priv->dev, "Error: mbox_send_message failure.\n");
+		dev_err(dev_ctx->priv->dev,
+			"%s: Error: mbox_send_message failure.", dev_ctx->devname);
 		return err;
 	}
 
@@ -172,38 +174,41 @@ static void ele_msg_send_rcv_cleanup(struct se_if_priv *priv)
 	unsigned long flags;
 
 	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+	priv->waiting_rsp_clbk_hdl.dev_ctx = NULL;
 	priv->waiting_rsp_clbk_hdl.rx_msg = NULL;
 	priv->waiting_rsp_clbk_hdl.rx_msg_sz = 0;
 	spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
 }
 
-/* API used for send/receive blocking call. */
-int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
-		     void *rx_msg, int exp_rx_msg_sz)
+/* API used for send/receive blocking calls. */
+int ele_msg_send_rcv(struct se_if_device_ctx *dev_ctx, void *tx_msg,
+		     int tx_msg_sz, void *rx_msg, int exp_rx_msg_sz)
 {
+	struct se_if_priv *priv = dev_ctx->priv;
 	unsigned long flags;
 	int err;
 
 	guard(mutex)(&priv->se_if_cmd_lock);
 
 	if (atomic_read(&priv->fw_busy)) {
-		dev_dbg(priv->dev, "ELE became unresponsive.\n");
+		dev_dbg(priv->dev, "%s: ELE became unresponsive.\n", dev_ctx->devname);
 		return -EBUSY;
 	}
 	reinit_completion(&priv->waiting_rsp_clbk_hdl.done);
 	/* Publish rx_msg/rx_msg_sz under the lock read by se_if_rx_callback(). */
 	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+	priv->waiting_rsp_clbk_hdl.dev_ctx = dev_ctx;
 	priv->waiting_rsp_clbk_hdl.rx_msg_sz = exp_rx_msg_sz;
 	priv->waiting_rsp_clbk_hdl.rx_msg = rx_msg;
 	spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
 
-	err = ele_msg_send(priv, tx_msg, tx_msg_sz);
+	err = ele_msg_send(dev_ctx, tx_msg, tx_msg_sz);
 	if (err < 0) {
 		ele_msg_send_rcv_cleanup(priv);
 		return err;
 	}
 
-	err = ele_msg_rcv(priv, &priv->waiting_rsp_clbk_hdl);
+	err = ele_msg_rcv(dev_ctx, &priv->waiting_rsp_clbk_hdl);
 
 	if (priv->waiting_rsp_clbk_hdl.signal_rcvd) {
 		/*
@@ -214,7 +219,8 @@ int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
 		if (err > 0)
 			err = -ERESTARTSYS;
 		priv->waiting_rsp_clbk_hdl.signal_rcvd = false;
-		dev_dbg(priv->dev, "Err[0x%x]:Interrupted by signal.", err);
+		dev_dbg(priv->dev, "%s: Err[0x%x]:Interrupted by signal.",
+			dev_ctx->devname, err);
 	}
 
 	ele_msg_send_rcv_cleanup(priv);
@@ -243,6 +249,7 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 {
 	struct se_clbk_handle *se_clbk_hdl;
 	struct device *dev = mbox_cl->dev;
+	const char *devname = NULL;
 	struct se_msg_hdr *header;
 	bool sz_mismatch = false;
 	struct se_if_priv *priv;
@@ -266,7 +273,7 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 	if (header->tag == priv->if_defs->cmd_tag) {
 		se_clbk_hdl = &priv->cmd_receiver_clbk_hdl;
 		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
-		if (!se_clbk_hdl->rx_msg) {
+		if (!se_clbk_hdl->dev_ctx || !se_clbk_hdl->rx_msg) {
 			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 			dev_warn(dev, "No command receiver registered for message: %.8x\n",
 				 *((u32 *)header));
@@ -280,8 +287,8 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 		 * SE_IOCTL_ENABLE_CMD_RCV and is not subject to the timeout/circuit-
 		 * breaker handling used for rsp_tag messages.
 		 */
-		dev_dbg(dev, "Selecting cmd receiver: for mesg header:0x%x.",
-			*(u32 *)header);
+		dev_dbg(dev, "Selecting cmd receiver:%s for mesg header:0x%x.",
+			se_clbk_hdl->dev_ctx->devname,  *(u32 *)header);
 
 		/*
 		 * Pre-allocated buffer of MAX_NVM_MSG_LEN
@@ -296,13 +303,14 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 		 * Clamp the copy length to the pre-allocated receiver buffer (MAX_NVM_MSG_LEN).
 		 */
 		se_clbk_hdl->rx_msg_sz = min_t(u32, rx_msg_sz, MAX_NVM_MSG_LEN);
+		devname = se_clbk_hdl->dev_ctx->devname;
 		memcpy(se_clbk_hdl->rx_msg, msg, se_clbk_hdl->rx_msg_sz);
 		complete(&se_clbk_hdl->done);
 		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 		if (sz_mismatch)
 			dev_err(dev,
-				"CMD-RCVER NVM: hdr(0x%x) with different sz(%d != %d).\n",
-				*(u32 *)header,
+				"%s: CMD-RCVER NVM: hdr(0x%x) with different sz(%d != %d).\n",
+				devname, *(u32 *)header,
 				(header->size << 2), rx_msg_sz);
 	} else if (header->tag == priv->if_defs->rsp_tag) {
 		bool exception_for_sz_mismatch = check_hdr_exception_for_sz(priv, header);
@@ -324,8 +332,8 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 			return;
 		}
 		exp_rx_msg_sz = se_clbk_hdl->rx_msg_sz;
-		dev_dbg(dev, "Selecting resp waiter: for mesg header:0x%x.",
-			*(u32 *)header);
+		dev_dbg(dev, "Selecting resp waiter:%s for mesg header:0x%x.",
+			se_clbk_hdl->dev_ctx->devname, *(u32 *)header);
 
 		/*
 		 * For rsp_tag traffic, the sender provides the expected response
@@ -337,14 +345,15 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 			sz_mismatch = true;
 
 		se_clbk_hdl->rx_msg_sz = min(rx_msg_sz, exp_rx_msg_sz);
+		devname = se_clbk_hdl->dev_ctx->devname;
 		memcpy(se_clbk_hdl->rx_msg, msg, se_clbk_hdl->rx_msg_sz);
 		complete(&se_clbk_hdl->done);
 		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 
 		if (sz_mismatch)
 			dev_err(dev,
-				"Rsp to CMD: hdr(0x%x) with different sz(%d != %d).\n",
-				*(u32 *)header,
+				"%s: Rsp to CMD: hdr(0x%x) with different sz(%d != %d).\n",
+				devname, *(u32 *)header,
 				(header->size << 2), exp_rx_msg_sz);
 	} else {
 		dev_err(dev, "Failed to select a device for message: %.8x\n",
diff --git a/drivers/firmware/imx/ele_common.h b/drivers/firmware/imx/ele_common.h
index 7bf2febefc45..07e6b6a1bafa 100644
--- a/drivers/firmware/imx/ele_common.h
+++ b/drivers/firmware/imx/ele_common.h
@@ -16,12 +16,12 @@
 
 int se_update_msg_chksum(u32 *msg, u32 msg_len);
 
-int ele_msg_rcv(struct se_if_priv *priv, struct se_clbk_handle *se_clbk_hdl);
+int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk_hdl);
 
-int ele_msg_send(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz);
+int ele_msg_send(struct se_if_device_ctx *dev_ctx, void *tx_msg, int tx_msg_sz);
 
-int ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, int tx_msg_sz,
-		     void *rx_msg, int exp_rx_msg_sz);
+int ele_msg_send_rcv(struct se_if_device_ctx *dev_ctx, void *tx_msg,
+		     int tx_msg_sz, void *rx_msg, int exp_rx_msg_sz);
 
 void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg);
 
diff --git a/drivers/firmware/imx/se_ctrl.c b/drivers/firmware/imx/se_ctrl.c
index 53091cc37e7e..a8974eef190b 100644
--- a/drivers/firmware/imx/se_ctrl.c
+++ b/drivers/firmware/imx/se_ctrl.c
@@ -284,6 +284,36 @@ static int get_se_soc_info(struct se_if_priv *priv, const struct se_soc_info *se
 	return 0;
 }
 
+static int init_misc_device_context(struct se_if_priv *priv, int ch_id,
+				    struct se_if_device_ctx **new_dev_ctx)
+{
+	const char *err_str = "Failed to allocate memory";
+	struct se_if_device_ctx *dev_ctx;
+	int ret = -ENOMEM;
+
+	dev_ctx = kzalloc_obj(*dev_ctx, GFP_KERNEL);
+
+	if (!dev_ctx)
+		return ret;
+
+	dev_ctx->devname = kasprintf(GFP_KERNEL, "%s0_ch%d",
+				     get_se_if_name(priv->if_defs->se_if_type),
+				     ch_id);
+	if (!dev_ctx->devname)
+		goto exit;
+
+	dev_ctx->priv = priv;
+	*new_dev_ctx = dev_ctx;
+
+	return 0;
+exit:
+	*new_dev_ctx = NULL;
+
+	kfree(dev_ctx->devname);
+	kfree(dev_ctx);
+	return dev_err_probe(priv->dev, ret, "%s", err_str);
+}
+
 static int se_if_request_channel(struct device *dev, struct mbox_chan **chan,
 				 struct mbox_client *cl, const char *name)
 {
@@ -328,6 +358,11 @@ static void se_if_probe_cleanup(void *plat_dev)
 
 	dev_set_drvdata(dev, NULL);
 
+	if (priv->priv_dev_ctx) {
+		kfree(priv->priv_dev_ctx->devname);
+		kfree(priv->priv_dev_ctx);
+	}
+
 	kfree(priv);
 }
 
@@ -425,6 +460,12 @@ static int se_if_probe(struct platform_device *pdev)
 		load_fw->imem_mgmt = true;
 	}
 
+	ret = init_misc_device_context(priv, 0, &priv->priv_dev_ctx);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Failed[0x%x] to create device contexts.",
+				     ret);
+
 	if (if_node->if_defs.se_if_type == SE_TYPE_ID_HSM) {
 		ret = get_se_soc_info(priv, se_info);
 		if (ret)
diff --git a/drivers/firmware/imx/se_ctrl.h b/drivers/firmware/imx/se_ctrl.h
index 54b2a262a2c3..dd4a1ea7e35a 100644
--- a/drivers/firmware/imx/se_ctrl.h
+++ b/drivers/firmware/imx/se_ctrl.h
@@ -20,6 +20,7 @@
 #define MESSAGING_VERSION_7		0x7
 
 struct se_clbk_handle {
+	struct se_if_device_ctx *dev_ctx;
 	struct completion done;
 	bool signal_rcvd;
 	u32 rx_msg_sz;
@@ -44,6 +45,12 @@ struct se_imem_buf {
 	u32 state;
 };
 
+/* Private struct for each char device instance. */
+struct se_if_device_ctx {
+	struct se_if_priv *priv;
+	const char *devname;
+};
+
 /* Header of the messages exchange with the EdgeLock Enclave */
 struct se_msg_hdr {
 	u8 ver;
@@ -106,6 +113,8 @@ struct se_if_priv {
 	struct se_fw_load_info load_fw;
 
 	atomic_t fw_busy;
+
+	struct se_if_device_ctx *priv_dev_ctx;
 };
 
 char *get_se_if_name(u8 se_if_id);

-- 
2.43.0

Re: [PATCH v34 4/7] firmware: imx: device context dedicated to priv

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] In `ele_get_info()`, a physical DMA buffer (`get_info_data`) is allocated and mapped for the firmware to write its response. If the firmware takes too long to respond, `ele_msg_send_rcv()` times out and returns `-ETIMEDOUT`, setting the firmware state to busy. However, on this error path, `ele_get_info()` calls `ele_get_info_cleanup()`, which unconditionally frees the DMA buffer (via `dma_free_coherent()` or `gen_pool_free()`). Because the firmware may still be processing the command, it could eventually finish and write its response to the now-freed physical address, leading to a DMA Use-After-Free that corrupts memory. The buffer must be quarantined (leaked) if the firmware is unresponsive.
--

--- Patch [4]: [PATCH v34 4/7] firmware: imx: device context dedicated to priv ---
commit c0e62ad2fda653db9c2508807fbec3d62a1f2511
Author: Pankaj Gupta <pankaj.gupta@nxp.com>

firmware: imx: device context dedicated to priv

This patch adds a private device context to se_if_priv to prepare for
misc-device context-based send-receive paths. It updates several firmware
message passing functions to take the new priv_dev_ctx instead of the
top-level priv structure.

> diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
> --- a/drivers/firmware/imx/ele_base_msg.c
> +++ b/drivers/firmware/imx/ele_base_msg.c
> @@ -71,8 +71,9 @@ int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
>  	tx_msg->data[0] = upper_32_bits(get_info_addr);
>  	tx_msg->data[1] = lower_32_bits(get_info_addr);
>  	tx_msg->data[2] = sizeof(*s_info);
> -	ret = ele_msg_send_rcv(priv, tx_msg, ELE_GET_INFO_REQ_MSG_SZ, rx_msg,
> -			       ELE_GET_INFO_RSP_MSG_SZ);
> +
> +	ret = ele_msg_send_rcv(priv->priv_dev_ctx, tx_msg, ELE_GET_INFO_REQ_MSG_SZ,
> +			       rx_msg, ELE_GET_INFO_RSP_MSG_SZ);
>  	if (ret < 0) {
>  		ele_get_info_cleanup(priv, get_info_data, get_info_addr, get_info_len);
>  		return ret;

[Severity: High]
If ele_msg_send_rcv() times out and returns -ETIMEDOUT, the firmware state is
marked as busy, but this error path calls ele_get_info_cleanup() which
unconditionally frees the DMA buffer get_info_data:

ele_get_info_cleanup(struct se_if_priv *priv, u32 *buf, dma_addr_t d_addr,
				 size_t size)
{
	if (priv->mem_pool)
		gen_pool_free(priv->mem_pool, (unsigned long)buf, size);
	else
		dma_free_coherent(priv->dev, size, buf, d_addr);
}

If the firmware is just slow and later completes the command, will it write
its response into this now-freed physical address, causing a DMA
use-after-free and memory corruption?

Should this buffer be quarantined instead of freed when the firmware is
unresponsive?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-imx-se-if-v34-0-7e4713d14e0a@nxp.com?part=4

[PATCH v34 5/7] firmware: imx: adds miscdev

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Adds the driver for communication interface to secure-enclave, that
enables exchanging messages with NXP secure enclave HW IP(s)
like EdgeLock Enclave, from:
- User-Space Applications via character driver.

ABI documentation for the NXP secure-enclave driver.

User-space library using this driver:
- i.MX Secure Enclave library:
  -- URL: https://github.com/nxp-imx/imx-secure-enclave.git,
- i.MX Secure Middle-Ware:
  -- URL: https://github.com/nxp-imx/imx-smw.git

Following checks are performed on the incoming msg-header,
to block exchanging invalid arbitrary commands:
- maximum allowed words,
- check if command-tag & response-tag are valid
- version,
- command id validation check, to allow limited base-line API(s)
  and restrict following:
  - exchanging power management commands.
  - reset requests.
  - BBSM configuration requests.
  - re-initializing the FW.
  - RNG init
  - CAAM resource release management
  - SE's internal memory management.
from user-space.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
---
Changes from v33 to v34:

Teardown vs. in-flight transaction (lost wakeup / unbind hang):
 - se_if_probe_cleanup() now sets priv->going_away under clbk_rx_lock
   instead of se_if_cmd_lock. se_if_cmd_lock is held across the whole
   blocking transaction, so acquiring it during unbind could stall for a
   full receive timeout. clbk_rx_lock is the short spinlock the sender
   holds while arming a transaction, so setting going_away under it and
   then calling complete_all() makes teardown and arming mutually
   exclusive and closes the lost-wakeup window.
 - complete_all() is issued before walking the device-context list so a
   waiter sleeping on the completion while holding dev_ctx->fops_lock is
   released before cleanup takes the same lock, avoiding an unbind hang.

ele_msg_send_rcv() arming:
 - going_away and fw_busy are now evaluated under clbk_rx_lock together
   with reinit_completion() and the buffer publish, so a new transaction
   is never armed concurrently with teardown.
 - going_away is checked before fw_busy so a caller racing unbind gets a
   permanent -ENODEV rather than a misleading retryable -EBUSY. fw_busy
   is only atomic_read() here, so no fw_busy_lock is taken and there is
   no deadlock. Teardown session/storage close commands issued on
   priv_dev_ctx are still let through so the kernel can resynchronise
   state with FW.

ele_msg_rcv() response classification:
 - Add se_clbk_handle::rx_delivered, set by se_if_rx_callback() under
   clbk_rx_lock only after a real response is copied. ele_msg_rcv() uses
   it to tell a genuine firmware response apart from a teardown-forced
   complete_all() that wakes the waiter with no data. Without this a
   teardown-time close response could be mistaken for the forced abort,
   failing the close and leaking its DMA buffer, and a forced wakeup
   could be mistaken for a response while the enclave still DMAs into the
   shared buffer. The forced-abort path returns -ENODEV and arms the
   circuit breaker so the buffer is quarantined, not freed.

Session/storage handle tracking (ele_uapi_allowed_fw_cmd()):
 - Reject a repeated ELE_SESSION_OPEN_REQ / ELE_STORAGE_OPEN_REQ with
   -EEXIST when a handle is already open, preventing a handle leak.
 - Reject ELE_SESSION_CLOSE_REQ / ELE_STORAGE_CLOSE_REQ with -ENXIO when
   no handle is open.

se_close_session() / se_close_storage():
 - Use __free(kfree) scope-based cleanup consistently and return directly
   instead of mixing it with goto-based cleanup.

Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260805-imx-se-if-v33-0-212e32ff0295@nxp.com?part=5

Reference:
- Link to v33: https://lore.kernel.org/r/20260805-imx-se-if-v33-0-212e32ff0295@nxp.com
---
 Documentation/ABI/testing/se-cdev   |   44 +
 drivers/firmware/imx/Makefile       |    2 +-
 drivers/firmware/imx/ele_base_msg.c |   84 +-
 drivers/firmware/imx/ele_base_msg.h |   19 +
 drivers/firmware/imx/ele_common.c   |  130 ++-
 drivers/firmware/imx/ele_common.h   |    5 +
 drivers/firmware/imx/ele_fw_api.c   |  186 ++++
 drivers/firmware/imx/ele_fw_api.h   |   29 +
 drivers/firmware/imx/se_ctrl.c      | 1601 ++++++++++++++++++++++++++++++++++-
 drivers/firmware/imx/se_ctrl.h      |   90 ++
 include/uapi/linux/se_ioctl.h       |   97 +++
 11 files changed, 2236 insertions(+), 51 deletions(-)

diff --git a/Documentation/ABI/testing/se-cdev b/Documentation/ABI/testing/se-cdev
new file mode 100644
index 000000000000..c6b8e16bda78
--- /dev/null
+++ b/Documentation/ABI/testing/se-cdev
@@ -0,0 +1,44 @@
+What:		/dev/<se>_mu[0-9]+_ch[0-9]+
+Date:		Mar 2025
+KernelVersion:	6.8
+Contact:	linux-imx@nxp.com, pankaj.gupta@nxp.com
+Description:
+		NXP offers multiple hardware IP(s) for secure enclaves like EdgeLock-
+		Enclave(ELE), SECO. The character device file descriptors
+		/dev/<se>_mu*_ch* are the interface between userspace NXP's secure-
+		enclave shared library and the kernel driver.
+
+		The ioctl(2)-based ABI is defined and documented in
+		[include]<linux/firmware/imx/ele_mu_ioctl.h>.
+		ioctl(s) are used primarily for:
+
+			- shared memory management
+			- allocation of I/O buffers
+			- getting mu info
+			- setting a dev-ctx as receiver to receive all the commands from FW
+			- getting SoC info
+			- send command and receive command response
+
+		The following file operations are supported:
+
+		open(2)
+		  Currently the only useful flags are O_RDWR.
+
+		read(2)
+		  Every read() from the opened character device context is waiting on
+		  wait_event_interruptible, that gets set by the registered mailbox callback
+		  function, indicating a message received from the firmware on message-
+		  unit.
+
+		write(2)
+		  Every write() to the opened character device context needs to acquire
+		  mailbox_lock before sending message on to the message unit.
+
+		close(2)
+		  Stops and frees up the I/O contexts that were associated
+		  with the file descriptor.
+
+Users:		https://github.com/nxp-imx/imx-secure-enclave.git,
+		https://github.com/nxp-imx/imx-smw.git,
+		crypto/skcipher,
+		drivers/nvmem/imx-ocotp-ele.c
diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 4412b15846b1..3f41131a0fdc 100644
--- a/drivers/firmware/imx/Makefile
+++ b/drivers/firmware/imx/Makefile
@@ -4,5 +4,5 @@ obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o imx-scu-irq.o rm.o imx-scu-soc.o
 obj-${CONFIG_IMX_SCMI_CPU_DRV}	+= sm-cpu.o
 obj-${CONFIG_IMX_SCMI_MISC_DRV}	+= sm-misc.o
 obj-${CONFIG_IMX_SCMI_LMM_DRV}	+= sm-lmm.o
-sec_enclave-objs		= se_ctrl.o ele_common.o ele_base_msg.o
+sec_enclave-objs		= se_ctrl.o ele_common.o ele_base_msg.o ele_fw_api.o
 obj-${CONFIG_IMX_SEC_ENCLAVE}	+= sec_enclave.o
diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
index b70e3ef88a16..2da8817af092 100644
--- a/drivers/firmware/imx/ele_base_msg.c
+++ b/drivers/firmware/imx/ele_base_msg.c
@@ -15,13 +15,57 @@
 
 #define FW_DBG_DUMP_FIXED_STR		"ELE"
 
+int ele_uapi_allowed_base_cmd(struct se_if_priv *priv,
+			      struct se_msg_hdr *header)
+{
+	switch (header->command) {
+	case ELE_PING_REQ: return 0;
+	case ELE_DEBUG_DUMP_REQ: return 0;
+	case ELE_OEM_AUTH_CONTAINER_REQ: return 0;
+	case ELE_OEM_VERIFY_IMAGE_REQ: return 0;
+	case ELE_OEM_REL_CONTAINER_REQ: return 0;
+	case ELE_FW_LIFE_CYCLE_REQ: return 0;
+	case ELE_READ_FUSE_REQ: return 0;
+	case ELE_GET_FW_VERS_REQ: return 0;
+	case ELE_RETURN_LIFE_CYCLE_REQ: return 0;
+	case ELE_GET_EVENT_REQ: return 0;
+	case ELE_COMMIT_REQ: return 0;
+	case ELE_GEN_KEY_BLOB_REQ: return 0;
+	case ELE_GET_FW_STATUS_REQ: return 0;
+	case ELE_XIP_DECRYPT_REQ: return 0;
+	case ELE_WRITE_FUSE: return 0;
+	case ELE_GET_INFO_REQ: return 0;
+	case ELE_DEV_ATTEST_REQ: return 0;
+	case ELE_WRITE_SHADOW_FUSE_REQ: return 0;
+	case ELE_READ_SHADOW_FUSE_REQ: return 0;
+	default:
+		return -EACCES;
+	}
+}
+
 static void ele_get_info_cleanup(struct se_if_priv *priv, u32 *buf, dma_addr_t d_addr,
 				 size_t size)
 {
-	if (priv->mem_pool)
-		gen_pool_free(priv->mem_pool, (unsigned long)buf, size);
-	else
-		dma_free_coherent(priv->dev, size, buf, d_addr);
+	/* For the case when priv->mem_pool != NULL:
+	 *
+	 *   If this probe-time transaction timed out, the firmware may
+	 *   still write into the SRAM buffer after this function returns.
+	 *   Do not release it back to the pool while the firmware-busy
+	 *   circuit breaker still marks this context as owning an
+	 *   outstanding transaction. The buffer is reclaimed with the
+	 *   device on unbind; leaking this fixed-size probe buffer is
+	 *   preferable to letting the firmware corrupt reused pool memory.
+	 *   This mirrors the guard already applied on the shared-memory
+	 *   cleanup path below.
+	 */
+
+	if (priv->mem_pool) {
+		if (se_is_fw_busy_ctx(priv->priv_dev_ctx))
+			return;
+		se_cleanup_mem_pool_buf(priv->priv_dev_ctx, true);
+	} else {
+		se_dev_ctx_shared_mem_cleanup(priv->priv_dev_ctx);
+	}
 }
 
 int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
@@ -34,6 +78,7 @@ int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
 	if (!priv)
 		return -EINVAL;
 
+	guard(mutex)(&priv->priv_dev_ctx->fops_lock);
 	memset(s_info, 0x0, sizeof(*s_info));
 
 	struct se_api_msg *tx_msg __free(kfree) =
@@ -47,24 +92,23 @@ int ele_get_info(struct se_if_priv *priv, struct ele_dev_info *s_info)
 		return -ENOMEM;
 
 	get_info_len = ELE_GET_INFO_BUFF_SZ;
-	if (priv->mem_pool)
-		get_info_data = gen_pool_dma_alloc(priv->mem_pool,
-						   get_info_len,
-						   &get_info_addr);
-	else
-		get_info_data = dma_alloc_coherent(priv->dev,
-						   get_info_len,
-						   &get_info_addr,
-						   GFP_KERNEL);
-	if (!get_info_data) {
-		dev_err(priv->dev,
-			"%s: Failed to allocate get_info_addr.", __func__);
-		return -ENOMEM;
+	if (priv->mem_pool) {
+		ret = se_get_mem_pool_buf(priv->priv_dev_ctx, &get_info_data,
+					  &get_info_addr, get_info_len);
+		if (ret) {
+			dev_err(priv->dev, "Failed[0x%x] to alloc from gen_pool.\n", ret);
+			return -ENOMEM;
+		}
+	} else {
+		ret = get_shared_mem_slot(priv->priv_dev_ctx,
+					  &get_info_len, &get_info_addr,
+					  &get_info_data);
+		if (ret) {
+			dev_err(priv->dev, "Failed to allocate buffer.\n");
+			return -ENOMEM;
+		}
 	}
 
-	/* gen_pool_dma_alloc() does not zero the buffer. */
-	memset(get_info_data, 0, get_info_len);
-
 	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
 			    ELE_GET_INFO_REQ, ELE_GET_INFO_REQ_MSG_SZ, true);
 
diff --git a/drivers/firmware/imx/ele_base_msg.h b/drivers/firmware/imx/ele_base_msg.h
index d532c3f49449..475074580dd7 100644
--- a/drivers/firmware/imx/ele_base_msg.h
+++ b/drivers/firmware/imx/ele_base_msg.h
@@ -16,6 +16,23 @@
 
 #define ELE_NONE_VAL			0x0
 
+#define ELE_OEM_AUTH_CONTAINER_REQ	0x87
+#define ELE_OEM_VERIFY_IMAGE_REQ	0x88
+#define ELE_OEM_REL_CONTAINER_REQ	0x89
+#define ELE_FW_LIFE_CYCLE_REQ		0x95
+#define ELE_READ_FUSE_REQ		0x97
+#define ELE_GET_FW_VERS_REQ		0x9d
+#define ELE_RETURN_LIFE_CYCLE_REQ	0xa0
+#define ELE_GET_EVENT_REQ		0xa2
+#define ELE_COMMIT_REQ			0xa8
+#define ELE_GEN_KEY_BLOB_REQ		0xaf
+#define ELE_GET_FW_STATUS_REQ		0xc5
+#define ELE_XIP_DECRYPT_REQ		0xc6
+#define ELE_WRITE_FUSE                  0xd6
+#define ELE_DEV_ATTEST_REQ              0xdb
+#define ELE_WRITE_SHADOW_FUSE_REQ       0xf2
+#define ELE_READ_SHADOW_FUSE_REQ        0xf3
+
 #define ELE_GET_INFO_REQ		0xda
 #define ELE_GET_INFO_REQ_MSG_SZ		0x10
 #define ELE_GET_INFO_RSP_MSG_SZ		0x08
@@ -97,4 +114,6 @@ int ele_service_swap(struct se_if_priv *priv, dma_addr_t addr,
 int ele_fw_authenticate(struct se_if_priv *priv, dma_addr_t contnr_addr,
 			dma_addr_t img_addr);
 int ele_debug_dump(struct se_if_priv *priv);
+int ele_uapi_allowed_base_cmd(struct se_if_priv *priv,
+			      struct se_msg_hdr *header);
 #endif
diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
index 707fb69431ba..73548451b762 100644
--- a/drivers/firmware/imx/ele_common.c
+++ b/drivers/firmware/imx/ele_common.c
@@ -5,6 +5,27 @@
 
 #include "ele_base_msg.h"
 #include "ele_common.h"
+#include "ele_fw_api.h"
+#include "se_ctrl.h"
+
+int se_chk_tx_msg_hdr(struct se_if_device_ctx *dev_ctx, struct se_msg_hdr *header)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	if (!header->size || header->size > MAX_WORD_SIZE)
+		return -EINVAL;
+
+	if (header->tag != priv->if_defs->cmd_tag &&
+	    header->tag != priv->if_defs->rsp_tag)
+		return -EINVAL;
+
+	if (header->ver == priv->if_defs->base_api_ver)
+		return ele_uapi_allowed_base_cmd(priv, header);
+	else if (header->ver == priv->if_defs->fw_api_ver)
+		return ele_uapi_allowed_fw_cmd(dev_ctx, header);
+
+	return -EINVAL;
+}
 
 /*
  * se_update_msg_chksum() - calculate and update message checksum word.
@@ -46,6 +67,25 @@ int se_update_msg_chksum(u32 *msg, u32 msg_len)
 	return 0;
 }
 
+static void se_mark_fw_busy(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->fw_busy_lock, flags);
+	if (!priv->fw_busy_dev_ctx) {
+		kref_get(&dev_ctx->refcount);
+		priv->fw_busy_dev_ctx = dev_ctx;
+		atomic_set(&priv->fw_busy, 1);
+	}
+	spin_unlock_irqrestore(&priv->fw_busy_lock, flags);
+}
+
+void set_se_rcv_msg_timeout(struct se_if_device_ctx *dev_ctx, u32 timeout_ms)
+{
+	dev_ctx->rcv_msg_timeout_jiffies = msecs_to_jiffies(timeout_ms);
+}
+
 int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk_hdl)
 {
 	struct se_if_priv *priv = dev_ctx->priv;
@@ -56,10 +96,20 @@ int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk
 	unsigned long flags;
 	int ret;
 
-	remaining_jiffies = msecs_to_jiffies(SE_RCV_MSG_DEFAULT_TIMEOUT_MS);
+	remaining_jiffies = dev_ctx->rcv_msg_timeout_jiffies;
 	if (se_clbk_hdl == &priv->waiting_rsp_clbk_hdl) {
 		is_rsp_wait_with_timeout = true;
 		deadline_jiffies = jiffies + remaining_jiffies;
+
+		/*
+		 * Internal kernel transactions run on priv_dev_ctx (probe
+		 * get_info/ping, FW auth, PM IMEM swap). They are not tied to a
+		 * restartable syscall, so wait uninterruptibly: PM freezer fake
+		 * signals must not abort them with -ERESTARTSYS. Userspace
+		 * waiters stay interruptible via the deferred-signal path below.
+		 */
+		if (se_clbk_hdl->dev_ctx == priv->priv_dev_ctx)
+			wait_uninterruptible = true;
 	}
 
 	do {
@@ -71,7 +121,7 @@ int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk
 				spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
 				se_clbk_hdl->rx_msg = NULL;
 				if (!completion_done(&se_clbk_hdl->done))
-					atomic_set(&priv->fw_busy, 1);
+					se_mark_fw_busy(dev_ctx);
 				spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 				ret = -ETIMEDOUT;
 				break;
@@ -119,7 +169,7 @@ int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk
 			spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
 			se_clbk_hdl->rx_msg = NULL;
 			if (!completion_done(&se_clbk_hdl->done))
-				atomic_set(&priv->fw_busy, 1);
+				se_mark_fw_busy(dev_ctx);
 
 			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 			ret = -ETIMEDOUT;
@@ -128,8 +178,35 @@ int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk
 				get_se_if_name(priv->if_defs->se_if_type));
 			break;
 		}
+
+		/*
+		 * A positive wait return normally means a real response. During
+		 * teardown, se_if_probe_cleanup() forces this wait to return via
+		 * complete_all() with no response, while the enclave may still
+		 * DMA into the shared buffer. Treat that as a failed transaction
+		 * and arm the circuit breaker so the buffer is quarantined, not
+		 * freed.
+		 *
+		 * rx_delivered tells the two apart: se_if_rx_callback() sets it
+		 * under clbk_rx_lock only after copying a real response. This
+		 * keeps teardown-time session/storage close responses from being
+		 * mistaken for the forced abort, which would fail the close and
+		 * leak its DMA buffer.
+		 */
+		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+		if (is_rsp_wait_with_timeout && atomic_read(&priv->going_away) &&
+		    !se_clbk_hdl->rx_delivered) {
+			se_clbk_hdl->rx_msg = NULL;
+			se_mark_fw_busy(dev_ctx);
+			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+			ret = -ENODEV;
+			break;
+		}
+		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+
 		ret = se_clbk_hdl->rx_msg_sz;
 		break;
+
 	} while (ret < 0);
 
 	return ret;
@@ -190,16 +267,42 @@ int ele_msg_send_rcv(struct se_if_device_ctx *dev_ctx, void *tx_msg,
 
 	guard(mutex)(&priv->se_if_cmd_lock);
 
+	/*
+	 * Arm the transaction under clbk_rx_lock. se_if_probe_cleanup() sets
+	 * going_away under this same lock, then complete_all()s, so checking
+	 * going_away and arming (reinit_completion() + publish) together makes
+	 * teardown and arming mutually exclusive and closes the lost-wakeup
+	 * window. priv_dev_ctx teardown-close commands are still let through.
+	 *
+	 * Check going_away before fw_busy so a caller racing unbind gets
+	 * -ENODEV, not a misleading retryable -EBUSY. fw_busy is only
+	 * atomic_read() here, so no fw_busy_lock is taken and there is no
+	 * deadlock.
+	 */
+	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+	if (atomic_read(&priv->going_away) &&
+	    (dev_ctx != priv->priv_dev_ctx ||
+	    !is_msg_xchng_for_tdown(tx_msg))) {
+		spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
+		return -ENODEV;
+	}
+
 	if (atomic_read(&priv->fw_busy)) {
+		spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
 		dev_dbg(priv->dev, "%s: ELE became unresponsive.\n", dev_ctx->devname);
 		return -EBUSY;
 	}
+
 	reinit_completion(&priv->waiting_rsp_clbk_hdl.done);
-	/* Publish rx_msg/rx_msg_sz under the lock read by se_if_rx_callback(). */
-	spin_lock_irqsave(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
 	priv->waiting_rsp_clbk_hdl.dev_ctx = dev_ctx;
 	priv->waiting_rsp_clbk_hdl.rx_msg_sz = exp_rx_msg_sz;
 	priv->waiting_rsp_clbk_hdl.rx_msg = rx_msg;
+	/*
+	 * Arm a fresh transaction: clear the delivered flag so a stale value
+	 * from a previous response cannot make ele_msg_rcv() mistake a
+	 * teardown-forced complete_all() for a genuine firmware response.
+	 */
+	priv->waiting_rsp_clbk_hdl.rx_delivered = false;
 	spin_unlock_irqrestore(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock, flags);
 
 	err = ele_msg_send(dev_ctx, tx_msg, tx_msg_sz);
@@ -248,6 +351,7 @@ static bool check_hdr_exception_for_sz(struct se_if_priv *priv,
 void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 {
 	struct se_clbk_handle *se_clbk_hdl;
+	bool schedule_fw_busy_work = false;
 	struct device *dev = mbox_cl->dev;
 	const char *devname = NULL;
 	struct se_msg_hdr *header;
@@ -325,9 +429,13 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 		se_clbk_hdl = &priv->waiting_rsp_clbk_hdl;
 		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
 		if (!se_clbk_hdl->rx_msg) {
-			/* Close circuit breaker on spinlock race */
-			atomic_set(&priv->fw_busy, 0);
+			if (atomic_read(&priv->fw_busy))
+				schedule_fw_busy_work = true;
 			spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+
+			if (schedule_fw_busy_work)
+				schedule_work(&priv->fw_busy_work);
+
 			dev_info(dev, "ELE responded (late), recovery FW available.");
 			return;
 		}
@@ -347,6 +455,12 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
 		se_clbk_hdl->rx_msg_sz = min(rx_msg_sz, exp_rx_msg_sz);
 		devname = se_clbk_hdl->dev_ctx->devname;
 		memcpy(se_clbk_hdl->rx_msg, msg, se_clbk_hdl->rx_msg_sz);
+		/*
+		 * Mark that a genuine firmware response was delivered. ele_msg_rcv()
+		 * reads this under clbk_rx_lock to avoid mistaking this response for
+		 * a teardown-forced complete_all() wakeup.
+		 */
+		se_clbk_hdl->rx_delivered = true;
 		complete(&se_clbk_hdl->done);
 		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
 
@@ -398,7 +512,7 @@ int se_val_rsp_hdr_n_status(struct se_if_priv *priv, struct se_api_msg *msg,
 		return -EINVAL;
 	}
 
-	if (header->size > SE_MU_HDR_WORD_SZ) {
+	if (header->size > SE_MU_HDR_WORD_SZ && (sz >> 2) > SE_MU_HDR_WORD_SZ) {
 		status = RES_STATUS(msg->data[0]);
 		if (status != priv->if_defs->success_tag) {
 			dev_dbg(priv->dev, "Command Id[%x], Response Failure = 0x%x",
diff --git a/drivers/firmware/imx/ele_common.h b/drivers/firmware/imx/ele_common.h
index 07e6b6a1bafa..b63a3fbf087a 100644
--- a/drivers/firmware/imx/ele_common.h
+++ b/drivers/firmware/imx/ele_common.h
@@ -9,11 +9,15 @@
 #include "se_ctrl.h"
 
 #define SE_RCV_MSG_DEFAULT_TIMEOUT_MS	3000
+#define SE_RCV_MSG_LONG_TIMEOUT_MS	5000000
 
 #define ELE_SUCCESS_IND			0xD6
 
 #define IMX_ELE_FW_DIR                 "imx/ele/"
 
+#define MAX_WORD_SIZE			0x20
+
+void set_se_rcv_msg_timeout(struct se_if_device_ctx *dev_ctx, u32 val);
 int se_update_msg_chksum(u32 *msg, u32 msg_len);
 
 int ele_msg_rcv(struct se_if_device_ctx *dev_ctx, struct se_clbk_handle *se_clbk_hdl);
@@ -42,4 +46,5 @@ int se_save_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem);
 
 int se_restore_imem_state(struct se_if_priv *priv, struct se_imem_buf *imem);
 
+int se_chk_tx_msg_hdr(struct se_if_device_ctx *dev_ctx, struct se_msg_hdr *header);
 #endif /*__ELE_COMMON_H__ */
diff --git a/drivers/firmware/imx/ele_fw_api.c b/drivers/firmware/imx/ele_fw_api.c
new file mode 100644
index 000000000000..2e98f36f0697
--- /dev/null
+++ b/drivers/firmware/imx/ele_fw_api.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2026 NXP
+ */
+
+#include "se_ctrl.h"
+#include "ele_common.h"
+#include "ele_fw_api.h"
+
+static bool se_cmd_receiver_allowed_cmd(u8 cmd)
+{
+	switch (cmd) {
+	case ELE_SESSION_CLOSE_REQ:
+	case ELE_STORAGE_CLOSE_REQ:
+	case ELE_STORAGE_MASTER_IMPORT_REQ:
+		return true;
+	default:
+		return false;
+	}
+}
+
+int ele_uapi_allowed_fw_cmd(struct se_if_device_ctx *dev_ctx, struct se_msg_hdr *header)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	bool is_cmd_receiver = false;
+	int ret = 0;
+
+	scoped_guard(mutex, &priv->modify_lock)
+		if (dev_ctx == priv->cmd_receiver_clbk_hdl.dev_ctx)
+			is_cmd_receiver = true;
+
+	if (header->tag == priv->if_defs->cmd_tag) {
+		if (is_cmd_receiver && !se_cmd_receiver_allowed_cmd(header->command))
+			return -EOPNOTSUPP;
+	}
+
+	if (header->tag == priv->if_defs->rsp_tag && !is_cmd_receiver)
+		return -EOPNOTSUPP;
+
+	switch (header->command) {
+	case ELE_SESSION_OPEN_REQ:
+		/* Might be cleared as part of tear down. */
+		ret = dev_ctx->sess_hdl ? -EEXIST : 0;
+		break;
+	case ELE_SESSION_CLOSE_REQ:
+		/* Might be cleared as part of tear down. */
+		ret = dev_ctx->sess_hdl ? 0 : -ENXIO;
+		break;
+	case ELE_STORAGE_OPEN_REQ:
+		/* Might be cleared as part of tear down. */
+		ret = dev_ctx->strg_hdl ? -EEXIST : 0;
+		break;
+	case ELE_STORAGE_CLOSE_REQ:
+		/* Might be cleared as part of tear down. */
+		ret = dev_ctx->strg_hdl ? 0 : -ENXIO;
+		break;
+	}
+
+	return ret;
+}
+
+void fw_api_specific_ops(struct se_if_device_ctx *dev_ctx, struct se_api_msg *rx_msg)
+{
+	struct se_msg_hdr *header = &rx_msg->header;
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	switch (header->command) {
+	case ELE_SESSION_OPEN_REQ:
+		dev_ctx->sess_hdl = rx_msg->data[1];
+		break;
+	case ELE_SESSION_CLOSE_REQ:
+		dev_ctx->sess_hdl = 0;
+		break;
+	case ELE_STORAGE_CLOSE_REQ:
+		scoped_guard(mutex, &priv->modify_lock)
+			unset_dev_ctx_as_command_receiver(dev_ctx);
+		dev_ctx->strg_hdl = 0;
+		break;
+	case ELE_STORAGE_OPEN_REQ: {
+		int rc = 0;
+
+		rc = set_dev_ctx_as_command_receiver(dev_ctx);
+		if (rc) {
+			dev_err(priv->dev,
+				"Failed to register %s as CMD-Receiver: %d\n",
+				dev_ctx->devname, rc);
+			break;
+		}
+		dev_ctx->strg_hdl = rx_msg->data[1];
+		break;
+	}
+	default:
+		dev_dbg(priv->dev, "%s: Unknown command = 0x%x.",
+			dev_ctx->devname, header->command);
+	}
+}
+
+/*
+ * Return true when tx_msg is one of the close requests the driver issues
+ * from its own teardown path (session/storage close). ele_msg_send_rcv()
+ * uses this to let those close messages through even after going_away is
+ * set, so the kernel can still resynchronise session/storage state with FW.
+ */
+bool is_msg_xchng_for_tdown(void *tx_msg)
+{
+	struct se_msg_hdr *header = &((struct se_api_msg *)tx_msg)->header;
+
+	return (header->command == ELE_SESSION_CLOSE_REQ ||
+		header->command == ELE_STORAGE_CLOSE_REQ);
+}
+
+int se_close_session(struct se_if_priv *priv, u32 session_hdl)
+{
+	struct se_api_msg *tx_msg __free(kfree) = NULL;
+	struct se_api_msg *rx_msg __free(kfree) = NULL;
+	int ret;
+
+	if (!priv || !priv->priv_dev_ctx)
+		return -EINVAL;
+
+	tx_msg = kzalloc(ELE_SESSION_CLOSE_REQ_SZ, GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	rx_msg = kzalloc(ELE_SESSION_CLOSE_RSP_SZ, GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_SESSION_CLOSE_REQ, ELE_SESSION_CLOSE_REQ_SZ, true);
+
+	tx_msg->data[0] = session_hdl;
+
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx,
+			       tx_msg,
+			       ELE_SESSION_CLOSE_REQ_SZ,
+			       rx_msg,
+			       ELE_SESSION_CLOSE_RSP_SZ);
+	if (ret < 0)
+		return ret;
+
+	ret = se_val_rsp_hdr_n_status(priv,
+				      rx_msg,
+				      ELE_SESSION_CLOSE_REQ,
+				      ELE_SESSION_CLOSE_RSP_SZ,
+				      false);
+	return ret;
+}
+
+int se_close_storage(struct se_if_priv *priv, u32 storage_hdl)
+{
+	struct se_api_msg *tx_msg __free(kfree) = NULL;
+	struct se_api_msg *rx_msg __free(kfree) = NULL;
+	int ret;
+
+	if (!priv || !priv->priv_dev_ctx)
+		return -EINVAL;
+
+	tx_msg = kzalloc(ELE_STORAGE_CLOSE_REQ_SZ, GFP_KERNEL);
+	if (!tx_msg)
+		return -ENOMEM;
+
+	rx_msg = kzalloc(ELE_STORAGE_CLOSE_RSP_SZ, GFP_KERNEL);
+	if (!rx_msg)
+		return -ENOMEM;
+
+	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
+			    ELE_STORAGE_CLOSE_REQ, ELE_STORAGE_CLOSE_REQ_SZ, true);
+
+	tx_msg->data[0] = storage_hdl;
+
+	ret = ele_msg_send_rcv(priv->priv_dev_ctx,
+			       tx_msg,
+			       ELE_STORAGE_CLOSE_REQ_SZ,
+			       rx_msg,
+			       ELE_STORAGE_CLOSE_RSP_SZ);
+	if (ret < 0)
+		return ret;
+
+	ret = se_val_rsp_hdr_n_status(priv,
+				      rx_msg,
+				      ELE_STORAGE_CLOSE_REQ,
+				      ELE_STORAGE_CLOSE_RSP_SZ,
+				      false);
+	return ret;
+}
diff --git a/drivers/firmware/imx/ele_fw_api.h b/drivers/firmware/imx/ele_fw_api.h
new file mode 100644
index 000000000000..c84fd583ad20
--- /dev/null
+++ b/drivers/firmware/imx/ele_fw_api.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2026 NXP
+ */
+
+#ifndef ELE_FW_API_H
+#define ELE_FW_API_H
+#include "se_ctrl.h"
+
+#define ELE_SESSION_OPEN_REQ            0x10u
+
+#define ELE_SESSION_CLOSE_REQ_SZ	0x08u
+#define ELE_SESSION_CLOSE_RSP_SZ	0x08u
+#define ELE_SESSION_CLOSE_REQ           0x11u
+
+#define ELE_STORAGE_OPEN_REQ            0xE0u
+
+#define ELE_STORAGE_CLOSE_REQ_SZ	0x08u
+#define ELE_STORAGE_CLOSE_RSP_SZ	0x08u
+#define ELE_STORAGE_CLOSE_REQ           0xE1u
+
+#define ELE_STORAGE_MASTER_IMPORT_REQ   0xE2u
+
+int ele_uapi_allowed_fw_cmd(struct se_if_device_ctx *dev_ctx, struct se_msg_hdr *header);
+void fw_api_specific_ops(struct se_if_device_ctx *dev_ctx, struct se_api_msg *rx_msg);
+bool is_msg_xchng_for_tdown(void *tx_msg);
+int se_close_session(struct se_if_priv *priv, u32 session_hdl);
+int se_close_storage(struct se_if_priv *priv, u32 storage_hdl);
+#endif /* ELE_FW_API_H */
diff --git a/drivers/firmware/imx/se_ctrl.c b/drivers/firmware/imx/se_ctrl.c
index a8974eef190b..207219804b14 100644
--- a/drivers/firmware/imx/se_ctrl.c
+++ b/drivers/firmware/imx/se_ctrl.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/bitfield.h>
+#include <linux/cleanup.h>
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/dev_printk.h>
@@ -15,6 +16,7 @@
 #include <linux/genalloc.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/kref.h>
 #include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
@@ -23,22 +25,21 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/sys_soc.h>
+#include <uapi/linux/se_ioctl.h>
 
 #include "ele_base_msg.h"
 #include "ele_common.h"
+#include "ele_fw_api.h"
 #include "se_ctrl.h"
 
+/* Maximum response buffer size in bytes for debug-dump replies. */
+#define MAX_ALLOWED_RX_MSG_SZ		ELE_DEBUG_DUMP_RSP_SZ
+#define MAX_ALLOWED_TX_MSG_SZ		SZ_4K
+
 #define MAX_SOC_INFO_DATA_SZ		256
 #define MBOX_TX_NAME			"tx"
 #define MBOX_RX_NAME			"rx"
 
-#define SE_TYPE_STR_DBG			"dbg"
-#define SE_TYPE_STR_HSM			"hsm"
-
-#define SE_TYPE_ID_DBG			0x1
-
-#define SE_TYPE_ID_HSM			0x2
-
 struct se_soc_dev_regn {
 	bool soc_dev_registered;
 	struct soc_device *soc_dev;
@@ -133,6 +134,13 @@ char *get_se_if_name(u8 se_if_id)
 	return "unknown";
 }
 
+static u32 get_se_soc_id(struct se_if_priv *priv)
+{
+	const struct se_if_node *if_node = device_get_match_data(priv->dev);
+
+	return if_node->se_info->soc_id;
+}
+
 static struct se_fw_load_info *get_load_fw_instance(struct se_if_priv *priv)
 {
 	return &priv->load_fw;
@@ -284,11 +292,319 @@ static int get_se_soc_info(struct se_if_priv *priv, const struct se_soc_info *se
 	return 0;
 }
 
+static int load_firmware(struct se_if_priv *priv, const u8 *se_img_file_to_load)
+{
+	const struct firmware *fw = NULL;
+	dma_addr_t se_fw_dma_addr;
+	u32 se_fw_buf_len;
+	void *se_fw_buf;
+	int ret;
+
+	if (!se_img_file_to_load) {
+		dev_err(priv->dev, "FW image is not provided.");
+		return -EINVAL;
+	}
+	ret = request_firmware(&fw, se_img_file_to_load, priv->dev);
+	if (ret)
+		return ret;
+
+	if (fw->size > U32_MAX) {
+		ret = -EFBIG;
+		release_firmware(fw);
+		return ret;
+	}
+	dev_info(priv->dev, "loading firmware %s.", se_img_file_to_load);
+
+	/*
+	 * Serialize access to priv_dev_ctx shared memory to prevent pos
+	 * corruption if two driver-internal callers run concurrently (e.g.
+	 * ele_get_info() racing with load_firmware()).
+	 */
+	scoped_guard(mutex, &priv->priv_dev_ctx->fops_lock) {
+		se_fw_buf_len = fw->size;
+		ret = get_shared_mem_slot(priv->priv_dev_ctx,
+					  &se_fw_buf_len, &se_fw_dma_addr,
+					  &se_fw_buf);
+		if (ret) {
+			dev_err(priv->dev, "Failed to allocate firmware shared buffer: %d\n",
+				ret);
+			release_firmware(fw);
+			return ret;
+		}
+
+		memcpy(se_fw_buf, fw->data, fw->size);
+		ret = ele_fw_authenticate(priv, se_fw_dma_addr, se_fw_dma_addr);
+		if (ret < 0) {
+			dev_err(priv->dev,
+				"Error %pe: Authenticate & load SE firmware %s.",
+				ERR_PTR(ret), se_img_file_to_load);
+			ret = -EPERM;
+		}
+		if (!se_is_fw_busy_ctx(priv->priv_dev_ctx))
+			se_dev_ctx_shared_mem_cleanup(priv->priv_dev_ctx);
+	}
+
+	release_firmware(fw);
+
+	return ret;
+}
+
+static int se_load_firmware(struct se_if_priv *priv)
+{
+	struct se_fw_load_info *load_fw = get_load_fw_instance(priv);
+	int ret = 0;
+
+	guard(mutex)(&load_fw->load_fw_lock);
+	if (!load_fw->is_fw_tobe_loaded)
+		return 0;
+
+	if (load_fw->imem.state == ELE_IMEM_STATE_BAD) {
+		ret = load_firmware(priv, load_fw->se_fw_img_nm->prim_fw_nm_in_rfs);
+		if (ret) {
+			dev_err(priv->dev, "Failed to load boot firmware.");
+			return -EPERM;
+		}
+	}
+
+	ret = load_firmware(priv, load_fw->se_fw_img_nm->seco_fw_nm_in_rfs);
+	if (ret) {
+		dev_err(priv->dev, "Failed to load runtime firmware.");
+		return -EPERM;
+	}
+
+	load_fw->is_fw_tobe_loaded = false;
+
+	return ret;
+}
+
+static int init_se_shared_mem(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	INIT_LIST_HEAD(&se_shared_mem_mgmt->pending_out);
+	INIT_LIST_HEAD(&se_shared_mem_mgmt->pending_in);
+
+	if (priv->mem_pool)
+		INIT_LIST_HEAD(&se_shared_mem_mgmt->mem_pool_buf_list);
+
+	se_shared_mem_mgmt->non_secure_mem.ptr =
+			dma_alloc_coherent(priv->dev, MAX_DATA_SIZE_PER_USER,
+					   &se_shared_mem_mgmt->non_secure_mem.dma_addr,
+					   GFP_KERNEL);
+	if (!se_shared_mem_mgmt->non_secure_mem.ptr)
+		return -ENOMEM;
+
+	se_shared_mem_mgmt->non_secure_mem.size = MAX_DATA_SIZE_PER_USER;
+	se_shared_mem_mgmt->non_secure_mem.pos = 0;
+
+	return 0;
+}
+
+static void cleanup_se_shared_mem(struct se_if_device_ctx *dev_ctx, bool reclaim)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_if_priv *priv = dev_ctx->priv;
+	bool free_dma_buf;
+
+	/*
+	 * mem_pool_buf_list is only initialised for interfaces that own a
+	 * gen_pool (priv->mem_pool != NULL). On interfaces without a pool
+	 * (e.g. imx93, which has no pool_name) the list head is left
+	 * zero-filled, so se_cleanup_mem_pool_buf() must not walk it here or
+	 * list_for_each_entry_safe() would dereference a NULL head and panic
+	 * the kernel on close/teardown. Skip the pool cleanup entirely when
+	 * there is no pool; there is nothing to reclaim in that case.
+	 */
+	if (priv->mem_pool)
+		se_cleanup_mem_pool_buf(dev_ctx, reclaim);
+
+	/* Guard against being called before shared memory was ever allocated
+	 * (e.g. probe failure before dma_alloc_coherent succeeded).
+	 */
+	if (!se_shared_mem_mgmt->non_secure_mem.ptr)
+		return;
+
+	/*
+	 * Decide whether the DMA buffer can be released before touching the
+	 * pending lists. se_dev_ctx_shared_mem_cleanup() resets
+	 * non_secure_mem.pos, so the "nothing staged" test must be sampled
+	 * here first. When reclaim is false the buffer is released only if no
+	 * data is still staged for the firmware; otherwise the enclave may
+	 * still be DMA-ing into it and the buffer is deliberately leaked to
+	 * avoid a DMA-after-free.
+	 */
+	free_dma_buf = reclaim || !se_shared_mem_mgmt->non_secure_mem.pos;
+
+	/*
+	 * Free any se_buf_desc items that were never consumed (e.g. when the
+	 * fd is closed while pending I/O buffers are still listed). This must
+	 * happen before the DMA backing memory is released to avoid a leak.
+	 */
+	se_dev_ctx_shared_mem_cleanup(dev_ctx);
+
+	if (free_dma_buf) {
+		dma_free_coherent(priv->dev, MAX_DATA_SIZE_PER_USER,
+				  se_shared_mem_mgmt->non_secure_mem.ptr,
+				  se_shared_mem_mgmt->non_secure_mem.dma_addr);
+	}
+
+	/*
+	 * Drop the host-side tracking unconditionally. On the reclaim path the
+	 * buffer has been freed. On the deliberate-leak path the buffer is
+	 * abandoned on purpose, so clearing the pointer here guarantees a later
+	 * cleanup pass (e.g. se_if_priv_release()) cannot double-free it.
+	 */
+	se_shared_mem_mgmt->non_secure_mem.ptr = NULL;
+	se_shared_mem_mgmt->non_secure_mem.dma_addr = 0;
+	se_shared_mem_mgmt->non_secure_mem.size = 0;
+	se_shared_mem_mgmt->non_secure_mem.pos = 0;
+}
+
+static int se_dev_ctx_cpy_out_data(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_buf_desc *b_desc, *temp;
+	bool do_cpy = true;
+
+	list_for_each_entry_safe(b_desc, temp, &se_shared_mem_mgmt->pending_out, link) {
+		if (b_desc->usr_buf_ptr && b_desc->shared_buf_ptr && do_cpy) {
+			dev_dbg(priv->dev, "Copying output data to user.");
+			if (do_cpy && copy_to_user(b_desc->usr_buf_ptr,
+						   b_desc->shared_buf_ptr,
+						   b_desc->size)) {
+				dev_err(priv->dev, "Failure copying output data to user.");
+				do_cpy = false;
+			}
+		}
+
+		if (b_desc->shared_buf_ptr)
+			memset(b_desc->shared_buf_ptr, 0, b_desc->size);
+
+		list_del(&b_desc->link);
+		kfree(b_desc);
+	}
+
+	return do_cpy ? 0 : -EFAULT;
+}
+
+/*
+ * Clean the used Shared Memory space,
+ * whether its Input Data copied from user buffers, or
+ * Data received from FW.
+ */
+void se_dev_ctx_shared_mem_cleanup(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct list_head *pending_lists[] = {&se_shared_mem_mgmt->pending_in,
+						&se_shared_mem_mgmt->pending_out};
+	struct se_buf_desc *b_desc, *temp;
+	bool is_fw_busy_dev_ctx;
+	int i;
+
+	/*
+	 * If this context is the one that caused a firmware timeout the shared
+	 * DMA buffers may still be actively read/written by the firmware.
+	 */
+	is_fw_busy_dev_ctx = se_is_fw_busy_ctx(dev_ctx);
+
+	for (i = 0; i < ARRAY_SIZE(pending_lists); i++) {
+		list_for_each_entry_safe(b_desc, temp, pending_lists[i], link) {
+			if (!is_fw_busy_dev_ctx && b_desc->shared_buf_ptr)
+				memset(b_desc->shared_buf_ptr, 0, b_desc->size);
+
+			list_del(&b_desc->link);
+			kfree(b_desc);
+		}
+	}
+
+	/*
+	 * Keep non_secure_mem.pos non-zero while this context still owns an
+	 * outstanding firmware transaction. A non-zero pos is the marker that
+	 * data is still staged for the enclave, which cleanup_se_shared_mem()
+	 * uses to decide the buffer must be leaked rather than freed. Resetting
+	 * it here would let a later teardown pass free a buffer the enclave may
+	 * still be DMA-ing into.
+	 */
+	if (!is_fw_busy_dev_ctx)
+		se_shared_mem_mgmt->non_secure_mem.pos = 0;
+}
+
+static struct se_buf_desc *add_b_desc_to_pending_list(void *shared_ptr_with_pos,
+						      struct se_ioctl_setup_iobuf *io,
+						      struct se_if_device_ctx *dev_ctx)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_buf_desc *b_desc = NULL;
+
+	b_desc = kzalloc_obj(*b_desc, GFP_KERNEL);
+	if (!b_desc)
+		return ERR_PTR(-ENOMEM);
+
+	b_desc->shared_buf_ptr = shared_ptr_with_pos;
+	b_desc->usr_buf_ptr = u64_to_user_ptr(io->user_buf);
+	b_desc->size = io->length;
+
+	if (io->flags & SE_IO_BUF_FLAGS_IS_INPUT) {
+		/*
+		 * buffer is input:
+		 * add an entry in the "pending input buffers" list so
+		 * that copied data can be cleaned from shared memory
+		 * later.
+		 */
+		list_add_tail(&b_desc->link, &se_shared_mem_mgmt->pending_in);
+	} else {
+		/*
+		 * buffer is output:
+		 * add an entry in the "pending out buffers" list so data
+		 * can be copied to user space when receiving Secure-Enclave
+		 * response.
+		 */
+		list_add_tail(&b_desc->link, &se_shared_mem_mgmt->pending_out);
+	}
+
+	return b_desc;
+}
+
+static void se_if_open_gate_release(struct kref *kref)
+{
+	struct se_if_open_gate *gate =
+		container_of(kref, struct se_if_open_gate, refcount);
+
+	kfree(gate);
+}
+
+static bool se_if_open_gate_get(struct se_if_open_gate *gate)
+{
+	if (!gate)
+		return false;
+
+	return kref_get_unless_zero(&gate->refcount);
+}
+
+static void se_if_open_gate_put(struct se_if_open_gate *gate)
+{
+	if (gate)
+		kref_put(&gate->refcount, se_if_open_gate_release);
+}
+
+/*
+ * Distinct lockdep class for the internal priv_dev_ctx fops_lock. Taking it
+ * while an open context's fops_lock is held (for example a firmware load
+ * triggered from an ioctl) is valid hierarchical locking, but shares the same
+ * class as the per-open fops_lock and would otherwise be misreported as
+ * recursive locking by lockdep.
+ */
+static struct lock_class_key se_priv_ctx_fops_key;
+
 static int init_misc_device_context(struct se_if_priv *priv, int ch_id,
-				    struct se_if_device_ctx **new_dev_ctx)
+				    struct se_if_device_ctx **new_dev_ctx,
+				    const struct file_operations *se_if_fops)
 {
 	const char *err_str = "Failed to allocate memory";
 	struct se_if_device_ctx *dev_ctx;
+	struct se_if_open_gate *gate = NULL;
 	int ret = -ENOMEM;
 
 	dev_ctx = kzalloc_obj(*dev_ctx, GFP_KERNEL);
@@ -296,19 +612,57 @@ static int init_misc_device_context(struct se_if_priv *priv, int ch_id,
 	if (!dev_ctx)
 		return ret;
 
+	dev_ctx->priv = priv;
 	dev_ctx->devname = kasprintf(GFP_KERNEL, "%s0_ch%d",
 				     get_se_if_name(priv->if_defs->se_if_type),
 				     ch_id);
 	if (!dev_ctx->devname)
 		goto exit;
 
-	dev_ctx->priv = priv;
+	mutex_init(&dev_ctx->fops_lock);
+	lockdep_set_class(&dev_ctx->fops_lock, &se_priv_ctx_fops_key);
+
+	kref_init(&dev_ctx->refcount);
+	dev_ctx->cleanup_done = false;
 	*new_dev_ctx = dev_ctx;
+	set_se_rcv_msg_timeout(dev_ctx, SE_RCV_MSG_DEFAULT_TIMEOUT_MS);
+
+	ret = init_se_shared_mem(dev_ctx);
+	if (ret < 0)
+		goto exit;
+
+	gate = kzalloc_obj(*gate, GFP_KERNEL);
+	if (!gate) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	mutex_init(&gate->lock);
+	kref_init(&gate->refcount);    /* device-owned reference */
+	gate->priv = priv;
+	gate->dying = false;
+	priv->open_gate = gate;
+
+	/*
+	 * The miscdevice storage is now owned by the open gate object.
+	 * priv->priv_dev_ctx still keeps a pointer to that miscdevice.
+	 */
+	dev_ctx->miscdev = &gate->miscdev;
+
+	dev_ctx->miscdev->name = dev_ctx->devname;
+	dev_ctx->miscdev->minor = MISC_DYNAMIC_MINOR;
+	dev_ctx->miscdev->fops = se_if_fops;
+	dev_ctx->miscdev->parent = priv->dev;
 
 	return 0;
 exit:
 	*new_dev_ctx = NULL;
 
+	if (gate) {
+		priv->open_gate = NULL;
+		se_if_open_gate_put(gate);
+	}
+	cleanup_se_shared_mem(dev_ctx, true);
 	kfree(dev_ctx->devname);
 	kfree(dev_ctx);
 	return dev_err_probe(priv->dev, ret, "%s", err_str);
@@ -329,9 +683,25 @@ static int se_if_request_channel(struct device *dev, struct mbox_chan **chan,
 	return 0;
 }
 
+/*
+ * Forward declarations. se_if_probe_cleanup() and se_if_probe() are kept
+ * together as the teardown/probe pair, but several helpers, the file
+ * operations table and the firmware-busy work handler they reference are
+ * defined further down in this file.
+ */
+static void dlink_dev_ctx(struct se_if_device_ctx *dev_ctx);
+static void cleanup_dev_ctx(struct se_if_device_ctx *dev_ctx, bool is_fclose);
+static void se_clear_fw_busy(struct se_if_priv *priv);
+static void se_if_dev_ctx_release(struct kref *kref);
+static void se_if_priv_release(struct kref *kref);
+static int se_if_misc_register(struct se_if_priv *priv);
+static void se_fw_busy_work(struct work_struct *work);
+static const struct file_operations se_if_fops;
+
 static void se_if_probe_cleanup(void *plat_dev)
 {
 	struct platform_device *pdev = plat_dev;
+	struct se_if_device_ctx *dev_ctx;
 	struct device *dev = &pdev->dev;
 	struct se_if_priv *priv;
 
@@ -339,31 +709,122 @@ static void se_if_probe_cleanup(void *plat_dev)
 	if (!priv)
 		return;
 
+	/*
+	 * Announce teardown, then wake any in-flight waiter. going_away makes
+	 * ele_msg_send_rcv() bail out instead of arming a new transaction and
+	 * lets ele_msg_rcv() tell a teardown-forced completion apart from a
+	 * real response; it must be set before complete_all().
+	 *
+	 * Set it under clbk_rx_lock, not se_if_cmd_lock: se_if_cmd_lock is held
+	 * across the whole blocking transaction, so taking it here would stall
+	 * unbind for a full receive-timeout. clbk_rx_lock is the short spinlock
+	 * ele_msg_send_rcv() holds while arming, so this closes the lost-wakeup
+	 * window - the sender either sees going_away and bails before arming, or
+	 * armed first and this store (and complete_all()) is ordered after its
+	 * reinit_completion() - and supplies the ordering the relaxed atomics do
+	 * not.
+	 */
+	scoped_guard(spinlock_irqsave, &priv->waiting_rsp_clbk_hdl.clbk_rx_lock)
+		atomic_set(&priv->going_away, 1);
+	/*
+	 * Wake the waiter before iterating the device-context list. It sleeps on
+	 * this completion holding dev_ctx->fops_lock, which cleanup_dev_ctx()
+	 * below also takes, so completing first avoids an unbind hang. Runs
+	 * outside clbk_rx_lock; the going_away store above already orders it
+	 * against the arming path.
+	 */
+	complete_all(&priv->waiting_rsp_clbk_hdl.done);
+
+	/*
+	 * Mark the private device context as cleanup_done first.
+	 * This prevents new device contexts from being created in open().
+	 */
+	if (priv->priv_dev_ctx) {
+		/*
+		 * Mark cleanup_done under fops_lock so that se_if_fops_open(),
+		 * which checks cleanup_done while holding fops_lock, cannot
+		 * race past this and add a new device context after teardown.
+		 */
+		scoped_guard(mutex, &priv->priv_dev_ctx->fops_lock)
+			priv->priv_dev_ctx->cleanup_done = true;
+
+		if (priv->open_gate) {
+			scoped_guard(mutex, &priv->open_gate->lock) {
+				priv->open_gate->dying = true;
+				priv->open_gate->priv = NULL;
+			}
+		}
+
+		/*
+		 * misc_register() is deferred to the end of probe, so the
+		 * device may have a miscdev set up but never registered if
+		 * probe failed before se_if_misc_register(). Only deregister
+		 * when registration actually succeeded.
+		 */
+		if (priv->open_gate && priv->open_gate->registered &&
+		    priv->priv_dev_ctx->miscdev)
+			misc_deregister(priv->priv_dev_ctx->miscdev);
+	}
+
+	while (true) {
+		dev_ctx = NULL;
+
+		scoped_guard(mutex, &priv->modify_lock) {
+			if (list_empty(&priv->dev_ctx_list))
+				goto out_done;
+
+			dev_ctx = list_first_entry(&priv->dev_ctx_list,
+						   struct se_if_device_ctx, link);
+
+			/* pin this context so close() cannot free it under us */
+			kref_get(&dev_ctx->refcount);
+			dlink_dev_ctx(dev_ctx);
+		}
+
+		/*
+		 * Local cleanup outside the global lock avoids ABBA deadlock
+		 * with paths that already take dev_ctx->fops_lock first.
+		 */
+		cleanup_dev_ctx(dev_ctx, false);
+		kref_put(&dev_ctx->refcount, se_if_dev_ctx_release);
+	}
+out_done:
+
+	/*
+	 * Free the rx mailbox channel before cancelling fw_busy_work.
+	 * se_if_rx_callback() runs from the rx channel and can schedule
+	 * fw_busy_work when a late response arrives. If the channel were still
+	 * live after cancel_work_sync(), a callback could re-arm the work and
+	 * later dereference priv after it has been freed. Releasing the rx
+	 * channel first guarantees no further callbacks, so the subsequent
+	 * cancel_work_sync() is final.
+	 */
 	if (priv->rx_chan)
 		mbox_free_channel(priv->rx_chan);
 	if (priv->tx_chan)
 		mbox_free_channel(priv->tx_chan);
 
 	/*
-	 * Being device managed buffer, no need to free the buffer allocated
-	 * in se probe to store encrypted IMEM.
+	 * A timed-out synchronous command may have retained a dev_ctx through
+	 * priv->fw_busy_dev_ctx even after the fd was closed and the context was
+	 * removed from dev_ctx_list. If no late response arrived, release that
+	 * retained context during driver teardown.
+	 *
+	 * se_clear_fw_busy() is idempotent and internally checks
+	 * priv->fw_busy_dev_ctx under fw_busy_lock.
 	 */
+	se_clear_fw_busy(priv);
+	cancel_work_sync(&priv->fw_busy_work);
 
 	/*
-	 * No need to check, if reserved memory is allocated
-	 * before calling for its release. Or clearing the
-	 * un-set bit.
+	 * Being device managed buffer, no need to free the buffer allocated
+	 * in se probe to store encrypted IMEM.
 	 */
-	of_reserved_mem_device_release(dev);
 
 	dev_set_drvdata(dev, NULL);
 
-	if (priv->priv_dev_ctx) {
-		kfree(priv->priv_dev_ctx->devname);
-		kfree(priv->priv_dev_ctx);
-	}
-
-	kfree(priv);
+	/* Drop the initial reference - priv will be freed when last fd closes */
+	kref_put(&priv->refcount, se_if_priv_release);
 }
 
 static int se_if_probe(struct platform_device *pdev)
@@ -386,15 +847,30 @@ static int se_if_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	priv->dev = dev;
+	/*
+	 * Pin the parent device for the lifetime of priv. A file descriptor may
+	 * stay open after the device is unbound; close() then still passes
+	 * priv->dev to dma_free_coherent()/dev_warn(). Without this reference
+	 * the struct device could be freed while priv->dev still points at it,
+	 * so the reference is dropped in se_if_priv_release() via put_device().
+	 */
+	get_device(priv->dev);
+	kref_init(&priv->refcount);
 	priv->if_defs = &if_node->if_defs;
 	dev_set_drvdata(dev, priv);
 
 	mutex_init(&priv->se_if_cmd_lock);
+	mutex_init(&priv->modify_lock);
 	spin_lock_init(&priv->cmd_receiver_clbk_hdl.clbk_rx_lock);
 	spin_lock_init(&priv->waiting_rsp_clbk_hdl.clbk_rx_lock);
 	atomic_set(&priv->fw_busy, 0);
+	spin_lock_init(&priv->fw_busy_lock);
+	priv->fw_busy_dev_ctx = NULL;
+	INIT_WORK(&priv->fw_busy_work, se_fw_busy_work);
+
 	init_completion(&priv->waiting_rsp_clbk_hdl.done);
 	init_completion(&priv->cmd_receiver_clbk_hdl.done);
+	INIT_LIST_HEAD(&priv->dev_ctx_list);
 
 	ret = devm_add_action_or_reset(dev, se_if_probe_cleanup, pdev);
 	if (ret)
@@ -460,7 +936,7 @@ static int se_if_probe(struct platform_device *pdev)
 		load_fw->imem_mgmt = true;
 	}
 
-	ret = init_misc_device_context(priv, 0, &priv->priv_dev_ctx);
+	ret = init_misc_device_context(priv, 0, &priv->priv_dev_ctx, &se_if_fops);
 	if (ret)
 		return dev_err_probe(dev, ret,
 				     "Failed[0x%x] to create device contexts.",
@@ -472,12 +948,1093 @@ static int se_if_probe(struct platform_device *pdev)
 			return dev_err_probe(dev, ret, "Failed to fetch SoC Info.");
 	}
 
+	/*
+	 * All probe-time initialization is complete; expose the
+	 * interface to userspace last so that an open()/ioctl cannot
+	 * race against a not-yet-initialized device.
+	 */
+	ret = se_if_misc_register(priv);
+	if (ret)
+		return ret;
+
 	dev_info(dev, "i.MX secure-enclave: %s0 interface to firmware, configured.",
 		 get_se_if_name(priv->if_defs->se_if_type));
 
 	return ret;
 }
 
+/*
+ * Expose the interface to userspace. Deferred until the end of probe so
+ * the device node only becomes openable after SoC info has been fetched
+ * and, on SoCs with IMEM management, the encrypted-IMEM buffer has been
+ * allocated. This prevents userspace from opening the node and issuing
+ * commands against a partially initialized interface.
+ */
+static int se_if_misc_register(struct se_if_priv *priv)
+{
+	int ret;
+
+	ret = misc_register(priv->priv_dev_ctx->miscdev);
+	if (ret)
+		return dev_err_probe(priv->dev, ret,
+				     "Failed to register misc device.");
+
+	priv->open_gate->registered = true;
+
+	return 0;
+}
+
+static void se_if_priv_release(struct kref *kref)
+{
+	struct se_if_priv *priv = container_of(kref, struct se_if_priv, refcount);
+
+	/* Free priv_dev_ctx if it exists */
+	if (priv->priv_dev_ctx) {
+		/*
+		 * miscdev storage belongs to open_gate, not directly to
+		 * priv_dev_ctx. The gate should already have been detached
+		 * from priv during teardown.
+		 *
+		 * Reclaim the internal context's shared memory directly here
+		 * instead of through cleanup_dev_ctx(). Teardown already set
+		 * cleanup_done on priv_dev_ctx, so cleanup_dev_ctx() would
+		 * short-circuit and leak the host descriptors and the coherent
+		 * buffer. By this point the device is fully unbound; if this
+		 * context ever armed the firmware-busy breaker, se_clear_fw_busy()
+		 * has already run with reclaim=false and freed the host
+		 * descriptors, emptied the pool list and cleared
+		 * non_secure_mem.ptr. A reclaim=true pass here is therefore both
+		 * safe and idempotent: it releases the buffers for a normal
+		 * context and is a no-op for the abandoned firmware-busy one.
+		 */
+		scoped_guard(mutex, &priv->priv_dev_ctx->fops_lock)
+			cleanup_se_shared_mem(priv->priv_dev_ctx, true);
+
+		kfree(priv->priv_dev_ctx->devname);
+		kfree(priv->priv_dev_ctx);
+		priv->priv_dev_ctx = NULL;
+	}
+	/*
+	 * No need to check, if reserved memory is allocated
+	 * before calling for its release. Or clearing the
+	 * un-set bit.
+	 */
+	of_reserved_mem_device_release(priv->dev);
+
+	/*
+	 * Be defensive: if teardown did not already drop the device-owned
+	 * gate reference for some reason, release it here.
+	 */
+	if (priv->open_gate) {
+		se_if_open_gate_put(priv->open_gate);
+		priv->open_gate = NULL;
+	}
+
+	/*
+	 * Drop the reference on priv->dev taken in se_if_probe(). The device was
+	 * pinned so that a file descriptor closed after device unbind can still
+	 * safely pass priv->dev to dma_free_coherent()/dev_warn().
+	 */
+	put_device(priv->dev);
+
+	/* Free any remaining resources that weren't devm-managed */
+	kfree(priv);
+}
+
+static void se_if_dev_ctx_release(struct kref *kref)
+{
+	struct se_if_device_ctx *dev_ctx =
+		container_of(kref, struct se_if_device_ctx, refcount);
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	kfree(dev_ctx);
+
+	/* drop the priv reference owned by this device context */
+	kref_put(&priv->refcount, se_if_priv_release);
+}
+
+static void se_clear_fw_busy(struct se_if_priv *priv)
+{
+	struct se_if_device_ctx *dev_ctx = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->fw_busy_lock, flags);
+	dev_ctx = priv->fw_busy_dev_ctx;
+	priv->fw_busy_dev_ctx = NULL;
+	atomic_set(&priv->fw_busy, 0);
+	spin_unlock_irqrestore(&priv->fw_busy_lock, flags);
+
+	if (!dev_ctx)
+		return;
+
+	/*
+	 * The circuit breaker is cleared from two places, which need opposite
+	 * memory-reclaim policies:
+	 *
+	 *   1. se_fw_busy_work(): a late firmware response actually arrived.
+	 *      going_away is not set and the enclave has finished with the
+	 *      buffer, so a full reclaim (reclaim=true) is safe. Only do this
+	 *      once the owning fd has been closed (cleanup_done); while the fd
+	 *      is still open the buffer belongs to that context and is released
+	 *      on its normal close path.
+	 *
+	 *   2. se_if_probe_cleanup(): teardown. going_away is set and no
+	 *      response has been confirmed, so the enclave may still be
+	 *      DMA-writing into the shared buffer. Freeing it here would be a
+	 *      DMA-after-free. Pass reclaim=false so cleanup_se_shared_mem()
+	 *      frees only the host-side descriptors and deliberately leaks the
+	 *      DMA buffer that the enclave might still touch.
+	 */
+	scoped_guard(mutex, &dev_ctx->fops_lock) {
+		if (atomic_read(&priv->going_away)) {
+			/*
+			 * Fatal, but deliberately non-panic: the enclave is
+			 * unresponsive at unbind with a transaction still in
+			 * flight. Both the coherent staging buffer and any
+			 * gen_pool buffers this context owns are abandoned
+			 * (host descriptors freed, DMA-visible memory leaked)
+			 * to avoid a DMA-after-free while the enclave may still
+			 * be writing. Emit one headline error here rather than
+			 * per-buffer so the count of faulted contexts is clear.
+			 * Do not use WARN/BUG: this path is recoverable and
+			 * panic_on_warn kernels must not be brought down by it.
+			 */
+			dev_err(priv->dev,
+				"%s: FATAL: enclave stuck at unbind, DMA leaked.\n",
+				dev_ctx->devname);
+			cleanup_se_shared_mem(dev_ctx, false);
+		} else if (dev_ctx->cleanup_done) {
+			cleanup_se_shared_mem(dev_ctx, true);
+		}
+	}
+
+	kref_put(&dev_ctx->refcount, se_if_dev_ctx_release);
+}
+
+void unset_dev_ctx_as_command_receiver(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_api_msg *old_rx_msg = NULL;
+	struct se_clbk_handle *se_clbk_hdl;
+	unsigned long flags;
+
+	lockdep_assert_held(&priv->modify_lock);
+
+	se_clbk_hdl = &priv->cmd_receiver_clbk_hdl;
+
+	if (se_clbk_hdl->dev_ctx == dev_ctx) {
+		spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+		old_rx_msg = se_clbk_hdl->rx_msg;
+		se_clbk_hdl->dev_ctx = NULL;
+		se_clbk_hdl->rx_msg = NULL;
+		se_clbk_hdl->rx_msg_sz = 0;
+		spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+
+		kfree(old_rx_msg);
+		complete_all(&se_clbk_hdl->done);
+	}
+}
+
+int set_dev_ctx_as_command_receiver(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_api_msg *new_rx_msg = NULL;
+	struct se_clbk_handle *se_clbk_hdl;
+	unsigned long flags;
+
+	se_clbk_hdl = &priv->cmd_receiver_clbk_hdl;
+	guard(mutex)(&priv->modify_lock);
+	if (se_clbk_hdl->dev_ctx == dev_ctx)
+		return 0;
+
+	if (se_clbk_hdl->dev_ctx)
+		return -EBUSY;
+
+	if (!se_clbk_hdl->rx_msg) {
+		new_rx_msg = kzalloc(MAX_NVM_MSG_LEN, GFP_KERNEL);
+		if (!new_rx_msg)
+			return -ENOMEM;
+	}
+	spin_lock_irqsave(&se_clbk_hdl->clbk_rx_lock, flags);
+	if (new_rx_msg)
+		se_clbk_hdl->rx_msg = new_rx_msg;
+	reinit_completion(&se_clbk_hdl->done);
+	se_clbk_hdl->rx_msg_sz = MAX_NVM_MSG_LEN;
+	se_clbk_hdl->dev_ctx = dev_ctx;
+	dev_ctx->rcv_msg_timeout_jiffies = MAX_SCHEDULE_TIMEOUT;
+	spin_unlock_irqrestore(&se_clbk_hdl->clbk_rx_lock, flags);
+
+	return 0;
+}
+
+static void dlink_dev_ctx(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	unset_dev_ctx_as_command_receiver(dev_ctx);
+
+	if (!list_empty(&dev_ctx->link)) {
+		list_del_init(&dev_ctx->link);
+		priv->active_devctx_count--;
+	}
+}
+
+bool se_is_fw_busy_ctx(struct se_if_device_ctx *dev_ctx)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	unsigned long flags;
+	bool match;
+
+	spin_lock_irqsave(&priv->fw_busy_lock, flags);
+	match = priv->fw_busy_dev_ctx == dev_ctx;
+	spin_unlock_irqrestore(&priv->fw_busy_lock, flags);
+
+	return match;
+}
+
+static void cleanup_dev_ctx(struct se_if_device_ctx *dev_ctx, bool is_fclose)
+{
+	bool already_done;
+
+	scoped_guard(mutex, &dev_ctx->fops_lock) {
+		already_done = dev_ctx->cleanup_done;
+		if (!already_done) {
+			/*
+			 * Ask FW to drop this context's session and storage so
+			 * the kernel and FW stay in sync. Done here, under this
+			 * context's fops_lock only (not the global modify_lock),
+			 * because both close requests block on a firmware
+			 * round-trip; issuing them while modify_lock was held
+			 * would stall every other context for the FW timeout.
+			 *
+			 * Skip the round-trips once the FW path is marked busy.
+			 * fw_busy is armed when a synchronous transaction times
+			 * out; while it is set ele_msg_send_rcv() rejects further
+			 * commands with -EBUSY without waiting. It is only cleared
+			 * by se_clear_fw_busy(), which during unbind runs once
+			 * after this loop (or earlier from fw_busy_work only if a
+			 * genuine late FW response arrives). On a hung FW no late
+			 * response comes, so the breaker stays set for the rest of
+			 * the loop and the remaining closes would just return
+			 * -EBUSY and log spurious "failed to close" errors. Skip
+			 * them and emit a single warning instead.
+			 */
+			if (atomic_read(&dev_ctx->priv->fw_busy)) {
+				if (dev_ctx->strg_hdl || dev_ctx->sess_hdl)
+					dev_warn(dev_ctx->priv->dev,
+						 "%s: skipping session/storage close, FW is busy\n",
+						 dev_ctx->devname);
+			} else {
+				if (dev_ctx->strg_hdl && se_close_storage(dev_ctx->priv,
+									  dev_ctx->strg_hdl))
+					dev_err(dev_ctx->priv->dev, "failed to close storage.\n");
+				if (dev_ctx->sess_hdl && se_close_session(dev_ctx->priv,
+									  dev_ctx->sess_hdl))
+					dev_err(dev_ctx->priv->dev, "failed to close session.\n");
+			}
+			/*
+			 * fw_busy is caused by one timed-out synchronous transaction.
+			 * Only that transaction's dev_ctx may still have coherent
+			 * memory referenced by FW. Do not skip cleanup for unrelated
+			 * contexts while fw_busy is set.
+			 */
+			if (se_is_fw_busy_ctx(dev_ctx))
+				dev_warn(dev_ctx->priv->dev,
+					 "%s: deferring shared memory cleanup while FW is busy\n",
+					 dev_ctx->devname);
+			else
+				cleanup_se_shared_mem(dev_ctx, true);
+
+			kfree(dev_ctx->devname);
+			dev_ctx->devname = NULL;
+			dev_ctx->cleanup_done = true;
+		}
+	}
+
+	if (is_fclose)
+		kref_put(&dev_ctx->refcount, se_if_dev_ctx_release);
+}
+
+static void dlink_n_cleanup_dev_ctx(struct se_if_device_ctx *dev_ctx, bool is_fclose)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+
+	if (is_fclose) {
+		scoped_guard(mutex, &priv->modify_lock)
+			dlink_dev_ctx(dev_ctx);
+	}
+
+	cleanup_dev_ctx(dev_ctx, is_fclose);
+}
+
+static int init_device_context(struct se_if_priv *priv, int ch_id,
+			       struct se_if_device_ctx **new_dev_ctx)
+{
+	struct se_if_device_ctx *dev_ctx;
+	int ret = 0;
+
+	dev_ctx = kzalloc_obj(*dev_ctx, GFP_KERNEL);
+
+	if (!dev_ctx)
+		return -ENOMEM;
+
+	dev_ctx->devname = kasprintf(GFP_KERNEL, "%s0_ch%d",
+				     get_se_if_name(priv->if_defs->se_if_type),
+				     ch_id);
+	if (!dev_ctx->devname) {
+		kfree(dev_ctx);
+		return -ENOMEM;
+	}
+
+	mutex_init(&dev_ctx->fops_lock);
+	kref_init(&dev_ctx->refcount);
+	dev_ctx->priv = priv;
+	dev_ctx->cleanup_done = false;
+	INIT_LIST_HEAD(&dev_ctx->link);
+	set_se_rcv_msg_timeout(dev_ctx, SE_RCV_MSG_LONG_TIMEOUT_MS);
+	*new_dev_ctx = dev_ctx;
+
+	ret = init_se_shared_mem(dev_ctx);
+	if (ret < 0) {
+		kfree(dev_ctx->devname);
+		kfree(dev_ctx);
+		*new_dev_ctx = NULL;
+
+		return ret;
+	}
+
+	/* Take a reference to priv for this device context */
+	kref_get(&priv->refcount);
+
+	scoped_guard(mutex, &priv->modify_lock) {
+		list_add_tail(&dev_ctx->link, &priv->dev_ctx_list);
+		priv->active_devctx_count++;
+	}
+
+	return ret;
+}
+
+static int se_ioctl_cmd_snd_rcv_cleanup(struct se_if_device_ctx *dev_ctx, void __user *uarg,
+					struct se_ioctl_cmd_snd_rcv_rsp_info *cmd_snd_rcv_rsp_info)
+{
+	/* shared memory is allocated before this IOCTL */
+	se_dev_ctx_shared_mem_cleanup(dev_ctx);
+
+	if (cmd_snd_rcv_rsp_info->rx_buf_sz &&
+	    copy_to_user(uarg, cmd_snd_rcv_rsp_info, sizeof(*cmd_snd_rcv_rsp_info))) {
+		dev_err(dev_ctx->priv->dev, "%s: Failed to copy cmd_snd_rcv_rsp_info to user.",
+			dev_ctx->devname);
+		return -EFAULT;
+	}
+
+	return 0;
+}
+
+static int se_ioctl_cmd_snd_rcv_rsp_handler(struct se_if_device_ctx *dev_ctx,
+					    void __user *uarg)
+{
+	struct se_ioctl_cmd_snd_rcv_rsp_info cmd_snd_rcv_rsp_info = {0};
+	struct se_if_priv *priv = dev_ctx->priv;
+	int rsp_status_err = 0;
+	int cleanup_err = 0;
+	int err = 0;
+
+	if (copy_from_user(&cmd_snd_rcv_rsp_info, uarg,
+			   sizeof(cmd_snd_rcv_rsp_info))) {
+		dev_err(priv->dev,
+			"%s: Failed to copy cmd_snd_rcv_rsp_info from user.",
+			dev_ctx->devname);
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return -EFAULT;
+	}
+
+	if (cmd_snd_rcv_rsp_info.tx_buf_sz < SE_MU_HDR_SZ ||
+	    cmd_snd_rcv_rsp_info.tx_buf_sz > MAX_ALLOWED_TX_MSG_SZ) {
+		dev_err(priv->dev, "%s: User buffer too small/large(%d < %d)",
+			dev_ctx->devname, cmd_snd_rcv_rsp_info.tx_buf_sz,
+			cmd_snd_rcv_rsp_info.tx_buf_sz < SE_MU_HDR_SZ ? SE_MU_HDR_SZ :
+								MAX_ALLOWED_TX_MSG_SZ);
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return -ENOSPC;
+	}
+
+	struct se_api_msg *tx_msg __free(kfree) =
+		memdup_user(u64_to_user_ptr(cmd_snd_rcv_rsp_info.tx_buf),
+			    cmd_snd_rcv_rsp_info.tx_buf_sz);
+	if (IS_ERR(tx_msg)) {
+		err = PTR_ERR(tx_msg);
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return err;
+	}
+
+	err = se_chk_tx_msg_hdr(dev_ctx, &tx_msg->header);
+	if (err) {
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return err;
+	}
+
+	if (cmd_snd_rcv_rsp_info.rx_buf_sz < SE_MU_HDR_SZ ||
+	    cmd_snd_rcv_rsp_info.rx_buf_sz > MAX_ALLOWED_RX_MSG_SZ) {
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return -EINVAL;
+	}
+
+	if (tx_msg->header.tag != priv->if_defs->cmd_tag) {
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return -EINVAL;
+	}
+
+	if (tx_msg->header.ver == priv->if_defs->fw_api_ver &&
+	    get_load_fw_instance(priv)->is_fw_tobe_loaded) {
+		err = se_load_firmware(priv);
+		if (err) {
+			dev_err(priv->dev, "Could not send msg as FW is not loaded.");
+			se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+			return -EPERM;
+		}
+	}
+
+	struct se_api_msg *rx_msg __free(kfree) =
+		kzalloc(cmd_snd_rcv_rsp_info.rx_buf_sz, GFP_KERNEL);
+	if (!rx_msg) {
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+		return -ENOMEM;
+	}
+
+	err = ele_msg_send_rcv(dev_ctx, tx_msg, cmd_snd_rcv_rsp_info.tx_buf_sz,
+			       rx_msg, cmd_snd_rcv_rsp_info.rx_buf_sz);
+	if (err < 0) {
+		se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+
+		/*
+		 * -ERESTARTSYS here means the wait was interrupted by a signal
+		 * after the command had already been handed to (and possibly
+		 * executed by) the firmware. Returning -ERESTARTSYS lets the VFS
+		 * transparently restart the ioctl, which would re-run the command
+		 * with the just cleaned-up (zeroed) shared input buffers. Report
+		 * -EINTR instead so the syscall is not auto-restarted; userspace
+		 * can decide whether to reissue it.
+		 */
+		if (err == -ERESTARTSYS)
+			err = -EINTR;
+
+		return err;
+	}
+
+	/*
+	 * ele_msg_send_rcv() returns a positive received-message size on
+	 * success. Returning that raw size as the ioctl result would make a
+	 * successful transaction look like a positive (non-zero) return value
+	 * to userspace. Record the actual received size in rx_buf_sz for the
+	 * response copied back to userspace, then normalise err to 0 so the
+	 * ioctl reports plain success; the firmware status is conveyed to
+	 * userspace inside the response buffer itself.
+	 */
+	cmd_snd_rcv_rsp_info.rx_buf_sz = err;
+	err = 0;
+
+	dev_dbg(priv->dev, "%s: %s %s.", dev_ctx->devname, __func__,
+		"message received, start transmit to user");
+
+	rsp_status_err =
+		se_val_rsp_hdr_n_status(priv, rx_msg, tx_msg->header.command,
+					cmd_snd_rcv_rsp_info.rx_buf_sz,
+					tx_msg->header.ver == priv->if_defs->base_api_ver);
+
+	if (!rsp_status_err) {
+		err = se_dev_ctx_cpy_out_data(dev_ctx);
+		if (err < 0) {
+			se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+			return err;
+		}
+	}
+
+	/* Copy data from the buffer */
+	print_hex_dump_debug("to user ", DUMP_PREFIX_OFFSET, 4, 4, rx_msg,
+			     cmd_snd_rcv_rsp_info.rx_buf_sz, false);
+
+	if (copy_to_user(u64_to_user_ptr(cmd_snd_rcv_rsp_info.rx_buf), rx_msg,
+			 cmd_snd_rcv_rsp_info.rx_buf_sz)) {
+		dev_err(priv->dev, "%s: Failed to copy to user.", dev_ctx->devname);
+		err = -EFAULT;
+	}
+
+	cleanup_err = se_ioctl_cmd_snd_rcv_cleanup(dev_ctx, uarg, &cmd_snd_rcv_rsp_info);
+
+	if (cleanup_err && !err)
+		err = cleanup_err;
+
+	if (!err && !rsp_status_err)
+		fw_api_specific_ops(dev_ctx, rx_msg);
+
+	return err;
+}
+
+static int se_ioctl_get_mu_info(struct se_if_device_ctx *dev_ctx,
+				void __user *uarg)
+{
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_ioctl_get_if_info if_info;
+	struct se_if_node *if_node;
+	int err = 0;
+
+	if_node = container_of(priv->if_defs, typeof(*if_node), if_defs);
+
+	if_info.se_if_id = 0;
+	if_info.interrupt_idx = 0;
+	if_info.tz = 0;
+	if_info.did = 0;
+	if_info.cmd_tag = priv->if_defs->cmd_tag;
+	if_info.rsp_tag = priv->if_defs->rsp_tag;
+	if_info.success_tag = priv->if_defs->success_tag;
+	if_info.base_api_ver = priv->if_defs->base_api_ver;
+	if_info.fw_api_ver = priv->if_defs->fw_api_ver;
+
+	dev_dbg(priv->dev, "%s: info [se_if_id: %d, irq_idx: %d, tz: 0x%x, did: 0x%x].",
+		dev_ctx->devname, if_info.se_if_id, if_info.interrupt_idx, if_info.tz,
+		if_info.did);
+
+	if (copy_to_user(uarg, &if_info, sizeof(if_info))) {
+		dev_err(priv->dev, "%s: Failed to copy mu info to user.",
+			dev_ctx->devname);
+		err = -EFAULT;
+	}
+
+	return err;
+}
+
+static void rollback_shared_mem_pos(struct se_if_device_ctx *dev_ctx, u32 length)
+{
+	struct se_shared_mem *shared_mem = NULL;
+
+	shared_mem = &dev_ctx->se_shared_mem_mgmt.non_secure_mem;
+
+	if (WARN_ON_ONCE(length > shared_mem->pos)) {
+		shared_mem->pos = 0;
+		return;
+	}
+
+	shared_mem->pos -= length;
+}
+
+int get_shared_mem_slot(struct se_if_device_ctx *dev_ctx,
+			u32 *length, dma_addr_t *ele_dma_addr, void **ptr)
+{
+	struct se_shared_mem *shared_mem = NULL;
+	bool is_fw_busy_dev_ctx;
+	size_t aligned_len = 0;
+	u32 pos;
+
+	/*
+	 * If this context is the one that caused a firmware timeout the shared
+	 * DMA buffers may still be actively read/written by the firmware.
+	 */
+	is_fw_busy_dev_ctx = se_is_fw_busy_ctx(dev_ctx);
+	if (is_fw_busy_dev_ctx)
+		return -EBUSY;
+
+	aligned_len = round_up((size_t)*length, 8);
+	if (aligned_len < *length) {
+		dev_err(dev_ctx->priv->dev, "%s: Invalid buffer length.",
+			dev_ctx->devname);
+		return -EINVAL;
+	}
+
+	/* No specific requirement for this buffer. */
+	shared_mem = &dev_ctx->se_shared_mem_mgmt.non_secure_mem;
+
+	/* Check there is enough space in the shared memory. */
+	dev_dbg(dev_ctx->priv->dev, "%s: req_size = %zd, max_size= %d, curr_pos = %d",
+		dev_ctx->devname, aligned_len, shared_mem->size,
+		shared_mem->pos);
+
+	if (shared_mem->size < shared_mem->pos ||
+	    aligned_len > (shared_mem->size - shared_mem->pos)) {
+		dev_err(dev_ctx->priv->dev, "%s: Not enough space in shared memory.",
+			dev_ctx->devname);
+		return -ENOMEM;
+	}
+
+	/* Allocate space in shared memory. 8 bytes aligned. */
+	pos = shared_mem->pos;
+	shared_mem->pos += aligned_len;
+	*ele_dma_addr = (u64)shared_mem->dma_addr + pos;
+	*ptr = shared_mem->ptr + pos;
+	*length = aligned_len;
+
+	memset(shared_mem->ptr + pos, 0, aligned_len);
+
+	return 0;
+}
+
+/*
+ * Copy a buffer of data to/from the user and return the address to use in
+ * messages
+ */
+static int se_ioctl_setup_iobuf_handler(struct se_if_device_ctx *dev_ctx,
+					void __user *uarg)
+{
+	struct se_ioctl_setup_iobuf io = {0};
+	struct se_buf_desc *b_desc = NULL;
+	void *dma_buf_ptr = NULL;
+	dma_addr_t ele_dma_addr;
+	u32 aligned_len = 0;
+	int err = 0;
+
+	if (copy_from_user(&io, uarg, sizeof(io))) {
+		dev_err(dev_ctx->priv->dev, "%s: Failed copy iobuf config from user.",
+			dev_ctx->devname);
+		return -EFAULT;
+	}
+
+	dev_dbg(dev_ctx->priv->dev, "%s: io [buf: %p(%d) flag: %x].", dev_ctx->devname,
+		u64_to_user_ptr(io.user_buf), io.length, io.flags);
+
+	if (io.length == 0 || !io.user_buf) {
+		/*
+		 * Accept NULL pointers since some buffers are optional
+		 * in FW commands. In this case we should return 0 as
+		 * pointer to be embedded into the message.
+		 * Skip all data copy part of code below.
+		 */
+		io.ele_addr = 0;
+		goto copy;
+	}
+
+	aligned_len = io.length;
+	err = get_shared_mem_slot(dev_ctx, &aligned_len, &ele_dma_addr, &dma_buf_ptr);
+	if (err)
+		return err;
+
+	io.ele_addr = ele_dma_addr;
+	if ((io.flags & SE_IO_BUF_FLAGS_IS_INPUT) ||
+	    (io.flags & SE_IO_BUF_FLAGS_IS_IN_OUT)) {
+		/*
+		 * buffer is input:
+		 * copy data from user space to this allocated buffer.
+		 */
+		if (copy_from_user(dma_buf_ptr, u64_to_user_ptr(io.user_buf),
+				   io.length)) {
+			dev_err(dev_ctx->priv->dev,
+				"%s: Failed copy data to shared memory.",
+				dev_ctx->devname);
+			err = -EFAULT;
+			goto rollback;
+		}
+	}
+
+	b_desc = add_b_desc_to_pending_list(dma_buf_ptr, &io, dev_ctx);
+	if (IS_ERR(b_desc)) {
+		err = PTR_ERR(b_desc);
+		dev_err(dev_ctx->priv->dev, "%s: Failed to allocate/link b_desc.",
+			dev_ctx->devname);
+		goto rollback;
+	}
+
+copy:
+	/* Provide the EdgeLock Enclave address to user space only if success.*/
+	if (copy_to_user(uarg, &io, sizeof(io))) {
+		dev_err(dev_ctx->priv->dev, "%s: Failed to copy iobuff setup to user.",
+			dev_ctx->devname);
+		err = -EFAULT;
+		goto rollback;
+	}
+	return err;
+
+rollback:
+	if (!IS_ERR_OR_NULL(b_desc)) {
+		list_del(&b_desc->link);
+		kfree(b_desc);
+	}
+
+	if (dma_buf_ptr && aligned_len) {
+		memset(dma_buf_ptr, 0, aligned_len);
+		rollback_shared_mem_pos(dev_ctx, aligned_len);
+	}
+
+	return err;
+}
+
+/* IOCTL to provide SoC information */
+static int se_ioctl_get_se_soc_info_handler(struct se_if_device_ctx *dev_ctx,
+					    void __user *uarg)
+{
+	struct se_ioctl_get_soc_info soc_info;
+	int err = -EINVAL;
+
+	soc_info.soc_id = get_se_soc_id(dev_ctx->priv);
+	soc_info.soc_rev = var_se_info.soc_rev;
+
+	err = copy_to_user(uarg, (u8 *)(&soc_info), sizeof(soc_info));
+	if (err) {
+		dev_err(dev_ctx->priv->dev, "%s: Failed to copy soc info to user.",
+			dev_ctx->devname);
+		err = -EFAULT;
+	}
+
+	return err;
+}
+
+/*
+ * File operations for user-space
+ */
+
+/* Write a message to the MU. */
+static ssize_t se_if_fops_write(struct file *fp, const char __user *buf,
+				size_t size, loff_t *ppos)
+{
+	struct se_if_device_ctx *dev_ctx = fp->private_data;
+	struct se_if_priv *priv;
+	int err;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &dev_ctx->fops_lock) {
+		if (dev_ctx->cleanup_done)
+			return -ENODEV;
+
+		priv = dev_ctx->priv;
+
+		dev_dbg(priv->dev, "%s: write from buf (%p)%zu, ppos=%lld.", dev_ctx->devname,
+			buf, size, ((ppos) ? *ppos : 0));
+
+		if (dev_ctx != priv->cmd_receiver_clbk_hdl.dev_ctx) {
+			se_dev_ctx_shared_mem_cleanup(dev_ctx);
+			return -EINVAL;
+		}
+
+		if (size < SE_MU_HDR_SZ || size > MAX_ALLOWED_TX_MSG_SZ) {
+			dev_err(priv->dev, "%s: User buffer too small/large(%zu < %d)",
+				dev_ctx->devname, size,
+				size < SE_MU_HDR_SZ ? SE_MU_HDR_SZ :
+								MAX_ALLOWED_TX_MSG_SZ);
+			return -ENOSPC;
+		}
+
+		struct se_api_msg *tx_msg __free(kfree) = memdup_user(buf, size);
+		if (IS_ERR(tx_msg))
+			return PTR_ERR(tx_msg);
+
+		err = se_chk_tx_msg_hdr(dev_ctx, &tx_msg->header);
+		if (err)
+			return err;
+
+		print_hex_dump_debug("from user ", DUMP_PREFIX_OFFSET, 4, 4,
+				     tx_msg, size, false);
+
+		err = ele_msg_send(dev_ctx, tx_msg, size);
+
+		return err;
+	}
+}
+
+/*
+ * Read a message from the MU.
+ * Blocking until a message is available.
+ */
+static ssize_t se_if_fops_read(struct file *fp, char __user *buf, size_t size,
+			       loff_t *ppos)
+{
+	struct se_if_device_ctx *dev_ctx = fp->private_data;
+	u8 rx_msg_snap[MAX_NVM_MSG_LEN];
+	struct se_if_priv *priv;
+	unsigned long flags;
+	size_t copy_len;
+	int err;
+
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &dev_ctx->fops_lock) {
+		priv = dev_ctx->priv;
+
+		if (dev_ctx->cleanup_done)
+			return -ENODEV;
+
+		dev_dbg(priv->dev, "%s: read to buf %p(%zu), ppos=%lld.", dev_ctx->devname,
+			buf, size, ((ppos) ? *ppos : 0));
+
+		mutex_lock(&priv->modify_lock);
+		if (dev_ctx != priv->cmd_receiver_clbk_hdl.dev_ctx) {
+			mutex_unlock(&priv->modify_lock);
+			se_dev_ctx_shared_mem_cleanup(dev_ctx);
+			return -EINVAL;
+		}
+		mutex_unlock(&priv->modify_lock);
+	}
+
+	err = ele_msg_rcv(dev_ctx, &priv->cmd_receiver_clbk_hdl);
+	if (err < 0) {
+		if (err != -ERESTARTSYS)
+			dev_err(priv->dev,
+				"%s: Er[0x%x]: Signal Interrupted. Current act-dev-ctx count: %d.",
+				dev_ctx->devname, err, dev_ctx->priv->active_devctx_count);
+		return err;
+	}
+
+	/*
+	 * Reacquire fops_lock before touching any dev_ctx state (pending lists,
+	 * rx_msg) after the blocking wait. fops_lock was dropped before calling
+	 * ele_msg_rcv(). If cleanup_dev_ctx() ran concurrently it could have
+	 * freed the DMA buffers and the pending lists, leading to UAF and list
+	 * corruption. Re-checking cleanup_done under fops_lock prevents that.
+	 */
+	mutex_lock(&dev_ctx->fops_lock);
+
+	if (dev_ctx->cleanup_done) {
+		mutex_unlock(&dev_ctx->fops_lock);
+		return -ENODEV;
+	}
+
+	/*
+	 * Snapshot rx_msg pointer under clbk_rx_lock before releasing it.
+	 * unset_dev_ctx_as_command_receiver() can acquire the lock, NULL out
+	 * rx_msg, and free the buffer at any time after the unlock; using a
+	 * stale pointer from the shared field after the unlock is a UAF.
+	 */
+	scoped_guard(mutex, &priv->modify_lock) {
+		spin_lock_irqsave(&priv->cmd_receiver_clbk_hdl.clbk_rx_lock, flags);
+		if (priv->cmd_receiver_clbk_hdl.dev_ctx != dev_ctx ||
+		    !priv->cmd_receiver_clbk_hdl.rx_msg ||
+		    !priv->cmd_receiver_clbk_hdl.rx_msg_sz) {
+			spin_unlock_irqrestore(&priv->cmd_receiver_clbk_hdl.clbk_rx_lock, flags);
+			mutex_unlock(&dev_ctx->fops_lock);
+			return -ENODEV;
+		}
+		/* Taking snapshot is enough for the one common pre-allocated buffer. */
+		copy_len = min(size, priv->cmd_receiver_clbk_hdl.rx_msg_sz);
+		memcpy(rx_msg_snap, priv->cmd_receiver_clbk_hdl.rx_msg, copy_len);
+		priv->cmd_receiver_clbk_hdl.rx_msg_sz = 0;
+		spin_unlock_irqrestore(&priv->cmd_receiver_clbk_hdl.clbk_rx_lock, flags);
+
+		/* We may need to copy the output data to user before
+		 * delivering the completion message.
+		 */
+		err = se_dev_ctx_cpy_out_data(dev_ctx);
+		if (err < 0) {
+			se_dev_ctx_shared_mem_cleanup(dev_ctx);
+			mutex_unlock(&dev_ctx->fops_lock);
+			return err;
+		}
+		/* Copy data from the buffer using the snapshot taken under the lock. */
+		print_hex_dump_debug("to user ", DUMP_PREFIX_OFFSET, 4, 4,
+				     rx_msg_snap, copy_len, false);
+
+		err = copy_len;
+		if (copy_to_user(buf, rx_msg_snap, copy_len))
+			err = -EFAULT;
+
+		se_dev_ctx_shared_mem_cleanup(dev_ctx);
+		mutex_unlock(&dev_ctx->fops_lock);
+	}
+
+	return err;
+}
+
+/* Open a character device. */
+static int se_if_fops_open(struct inode *nd, struct file *fp)
+{
+	struct miscdevice *miscdev = fp->private_data;
+	struct se_if_open_gate *gate;
+	struct se_if_device_ctx *misc_dev_ctx;
+	struct se_if_device_ctx *dev_ctx;
+	struct se_if_priv *priv;
+	int err = 0;
+
+	gate = container_of(miscdev, struct se_if_open_gate, miscdev);
+
+	if (!se_if_open_gate_get(gate))
+		return -ENODEV;
+
+	if (mutex_lock_interruptible(&gate->lock)) {
+		se_if_open_gate_put(gate);
+		return -ERESTARTSYS;
+	}
+
+	if (gate->dying || !gate->priv ||
+	    !kref_get_unless_zero(&gate->priv->refcount)) {
+		err = -ENODEV;
+		goto out_unlock_gate;
+	}
+
+	priv = gate->priv;
+	mutex_unlock(&gate->lock);
+
+	misc_dev_ctx = priv->priv_dev_ctx;
+
+	if (mutex_lock_interruptible(&misc_dev_ctx->fops_lock)) {
+		err = -ERESTARTSYS;
+		goto out_put_priv;
+	}
+
+	if (misc_dev_ctx->cleanup_done) {
+		err = -ENODEV;
+		goto out_unlock_misc;
+	}
+
+	priv->dev_ctx_mono_count++;
+	err = init_device_context(priv, priv->dev_ctx_mono_count, &dev_ctx);
+	if (err) {
+		dev_err(priv->dev, "Failed[0x%x] to create dev-ctx.", err);
+		goto out_unlock_misc;
+	}
+
+	fp->private_data = dev_ctx;
+
+out_unlock_misc:
+	mutex_unlock(&misc_dev_ctx->fops_lock);
+out_put_priv:
+	kref_put(&priv->refcount, se_if_priv_release);
+	se_if_open_gate_put(gate);
+	return err;
+out_unlock_gate:
+	mutex_unlock(&gate->lock);
+	se_if_open_gate_put(gate);
+	return err;
+}
+
+/* Close a character device. */
+static int se_if_fops_close(struct inode *nd, struct file *fp)
+{
+	struct se_if_device_ctx *dev_ctx = fp->private_data;
+
+	dlink_n_cleanup_dev_ctx(dev_ctx, true);
+
+	return 0;
+}
+
+/* IOCTL entry point of a character device */
+static long se_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+	struct se_if_device_ctx *dev_ctx = fp->private_data;
+	struct se_if_priv *priv;
+	void __user *uarg = (void __user *)arg;
+	long err;
+
+	/* Prevent race during change of device context */
+	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &dev_ctx->fops_lock) {
+		if (dev_ctx->cleanup_done)
+			return -ENODEV;
+
+		priv = dev_ctx->priv;
+
+		switch (cmd) {
+		case SE_IOCTL_ENABLE_CMD_RCV: {
+			err = set_dev_ctx_as_command_receiver(dev_ctx);
+			if (err)
+				dev_err(priv->dev, "Failed to register %s as CMD-Receiver: %ld\n",
+					dev_ctx->devname, err);
+		break;
+		}
+		case SE_IOCTL_GET_MU_INFO:
+			err = se_ioctl_get_mu_info(dev_ctx, uarg);
+			break;
+		case SE_IOCTL_SETUP_IOBUF:
+			err = se_ioctl_setup_iobuf_handler(dev_ctx, uarg);
+			break;
+		case SE_IOCTL_GET_SOC_INFO:
+			err = se_ioctl_get_se_soc_info_handler(dev_ctx, uarg);
+			break;
+		case SE_IOCTL_CMD_SEND_RCV_RSP:
+			err = se_ioctl_cmd_snd_rcv_rsp_handler(dev_ctx, uarg);
+			break;
+		default:
+			err = -ENOTTY;
+			dev_dbg(priv->dev, "%s: IOCTL %.8x not supported.",
+				dev_ctx->devname, cmd);
+		}
+	}
+
+	return err;
+}
+
+/* Char driver setup */
+static const struct file_operations se_if_fops = {
+	.open		= se_if_fops_open,
+	.owner		= THIS_MODULE,
+	.release	= se_if_fops_close,
+	.unlocked_ioctl = se_ioctl,
+	.compat_ioctl   = compat_ptr_ioctl,
+	.read		= se_if_fops_read,
+	.write		= se_if_fops_write,
+};
+
+int se_get_mem_pool_buf(struct se_if_device_ctx *dev_ctx, void **buf,
+			dma_addr_t *daddr, u32 len)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_buf_desc *b_desc = NULL;
+
+	lockdep_assert_held(&dev_ctx->fops_lock);
+
+	if (se_is_fw_busy_ctx(dev_ctx))
+		return -EBUSY;
+
+	b_desc = kzalloc_obj(*b_desc, GFP_KERNEL);
+	if (!b_desc)
+		return -ENOMEM;
+
+	/*
+	 * gen_pool is internally thread-safe, so contexts may allocate
+	 * concurrently. The buffer is tracked on this context's own
+	 * mem_pool_buf_list and released on its cleanup path.
+	 */
+	*buf = gen_pool_dma_alloc(priv->mem_pool, len, daddr);
+	if (!*buf) {
+		dev_err(priv->dev, "Failed to alloc from gen_pool.\n");
+		kfree(b_desc);
+		return -ENOMEM;
+	}
+
+	/* gen_pool_dma_alloc() does not zero the buffer. */
+	memset(*buf, 0, len);
+	b_desc->shared_buf_ptr = *buf;
+	b_desc->size = len;
+
+	list_add_tail(&b_desc->link, &se_shared_mem_mgmt->mem_pool_buf_list);
+
+	return 0;
+}
+
+void se_cleanup_mem_pool_buf(struct se_if_device_ctx *dev_ctx, bool reclaim)
+{
+	struct se_shared_mem_mgmt_info *se_shared_mem_mgmt = &dev_ctx->se_shared_mem_mgmt;
+	struct se_if_priv *priv = dev_ctx->priv;
+	struct se_buf_desc *b_desc, *temp;
+
+	/*
+	 * Free only the buffers this context allocated. A context that never
+	 * used the pool has an empty list, so this is a no-op for it.
+	 *
+	 * Unlike the coherent staging buffer, the pool path needs no
+	 * "nothing staged" (pos) gate on the reclaim=false leg. Pool buffers
+	 * are ephemeral, per-transaction allocations: se_get_mem_pool_buf()
+	 * refuses to allocate once the context is fw_busy, ele_msg_send_rcv()
+	 * refuses to start a new command while fw_busy, and the success path
+	 * frees the whole list via se_cleanup_mem_pool_buf(reclaim=true)
+	 * before returning. se_if_cmd_lock serialises synchronous commands, so
+	 * at most one transaction is outstanding. The only way to reach here
+	 * with reclaim=false and a non-empty list is the single fw_busy
+	 * context still owning the buffer(s) from the one timed-out
+	 * transaction. Those buffers are exactly the in-flight ones the
+	 * enclave may still be DMA-ing into, so leaving them on the list (no
+	 * gen_pool_free) deliberately leaks them to avoid a DMA-after-free -
+	 * there are no already-consumed pool buffers to reclaim on this leg.
+	 */
+	list_for_each_entry_safe(b_desc, temp, &se_shared_mem_mgmt->mem_pool_buf_list, link) {
+		if (reclaim)
+			gen_pool_free(priv->mem_pool,
+				      (unsigned long)b_desc->shared_buf_ptr,
+				      b_desc->size);
+		list_del(&b_desc->link);
+		kfree(b_desc);
+	}
+}
+
+static void se_fw_busy_work(struct work_struct *work)
+{
+	struct se_if_priv *priv =
+		container_of(work, struct se_if_priv, fw_busy_work);
+
+	se_clear_fw_busy(priv);
+}
+
 static int se_suspend(struct device *dev)
 {
 	struct se_if_priv *priv = dev_get_drvdata(dev);
diff --git a/drivers/firmware/imx/se_ctrl.h b/drivers/firmware/imx/se_ctrl.h
index dd4a1ea7e35a..35389095ed1c 100644
--- a/drivers/firmware/imx/se_ctrl.h
+++ b/drivers/firmware/imx/se_ctrl.h
@@ -10,20 +10,40 @@
 #include <linux/miscdevice.h>
 #include <linux/mailbox_client.h>
 #include <linux/semaphore.h>
+#include <linux/workqueue.h>
 
 #define MAX_FW_LOAD_RETRIES		50
 #define SE_MSG_WORD_SZ			0x4
 
 #define RES_STATUS(x)			FIELD_GET(0x000000ff, x)
+#define MAX_DATA_SIZE_PER_USER		(128 * 1024)
 #define MAX_NVM_MSG_LEN			(256)
 #define MESSAGING_VERSION_6		0x6
 #define MESSAGING_VERSION_7		0x7
 
+struct se_if_open_gate {
+	struct miscdevice miscdev;
+	struct se_if_priv *priv;
+	/* to lock to update the structure */
+	struct mutex lock;
+	struct kref refcount;
+	bool dying;
+	/* set once misc_register() has succeeded (deferred to probe end) */
+	bool registered;
+};
+
 struct se_clbk_handle {
 	struct se_if_device_ctx *dev_ctx;
 	struct completion done;
 	bool signal_rcvd;
+	/*
+	 * Set under clbk_rx_lock once a real response is copied into rx_msg,
+	 * cleared when a new transaction is armed. Lets ele_msg_rcv() tell a
+	 * genuine response from a teardown-forced complete_all() with no data.
+	 */
+	bool rx_delivered;
 	u32 rx_msg_sz;
+
 	/*
 	 * Assignment of the rx_msg buffer to held till the
 	 * received content as part callback function, is copied.
@@ -45,10 +65,46 @@ struct se_imem_buf {
 	u32 state;
 };
 
+struct se_buf_desc {
+	u8 *shared_buf_ptr;
+	void __user *usr_buf_ptr;
+	u32 size;
+	struct list_head link;
+};
+
+struct se_shared_mem {
+	dma_addr_t dma_addr;
+	u32 size;
+	u32 pos;
+	u8 *ptr;
+};
+
+struct se_shared_mem_mgmt_info {
+	struct list_head mem_pool_buf_list;
+	struct list_head pending_in;
+	struct list_head pending_out;
+
+	struct se_shared_mem non_secure_mem;
+};
+
 /* Private struct for each char device instance. */
 struct se_if_device_ctx {
 	struct se_if_priv *priv;
+	struct miscdevice *miscdev;
 	const char *devname;
+	u32 sess_hdl;
+	u32 strg_hdl;
+	bool cleanup_done;
+	unsigned long rcv_msg_timeout_jiffies;
+
+	/* process one file operation at a time. */
+	struct mutex fops_lock;
+
+	struct se_shared_mem_mgmt_info se_shared_mem_mgmt;
+	struct list_head link;
+
+	/* Add reference counting */
+	struct kref refcount;
 };
 
 /* Header of the messages exchange with the EdgeLock Enclave */
@@ -113,9 +169,43 @@ struct se_if_priv {
 	struct se_fw_load_info load_fw;
 
 	atomic_t fw_busy;
+	/*
+	 * Set once teardown begins. New synchronous transactions are rejected
+	 * and a teardown-forced completion is not mistaken for a real firmware
+	 * response.
+	 */
+	atomic_t going_away;
+	/*
+	 * Serialise the fw_busy_dev_ctx and fw_busy state updates between the
+	 * timeout path, late-response callback/work, and teardown.
+	 */
+	spinlock_t fw_busy_lock;
+	struct se_if_device_ctx *fw_busy_dev_ctx;
+	struct work_struct fw_busy_work;
 
 	struct se_if_device_ctx *priv_dev_ctx;
+	struct list_head dev_ctx_list;
+
+	/* prevent modifying priv member variable in parallel. */
+	struct mutex modify_lock;
+	u32 active_devctx_count;
+	u32 dev_ctx_mono_count;
+
+	/* Add reference counting */
+	struct kref refcount;
+
+	/* stable gate used by .open() */
+	struct se_if_open_gate *open_gate;
 };
 
 char *get_se_if_name(u8 se_if_id);
+void unset_dev_ctx_as_command_receiver(struct se_if_device_ctx *dev_ctx);
+int set_dev_ctx_as_command_receiver(struct se_if_device_ctx *dev_ctx);
+bool se_is_fw_busy_ctx(struct se_if_device_ctx *dev_ctx);
+void se_dev_ctx_shared_mem_cleanup(struct se_if_device_ctx *dev_ctx);
+int get_shared_mem_slot(struct se_if_device_ctx *dev_ctx,
+			u32 *length, dma_addr_t *ele_dma_addr, void **ptr);
+int se_get_mem_pool_buf(struct se_if_device_ctx *dev_ctx, void **buf,
+			dma_addr_t *daddr, u32 len);
+void se_cleanup_mem_pool_buf(struct se_if_device_ctx *dev_ctx, bool reclaim);
 #endif
diff --git a/include/uapi/linux/se_ioctl.h b/include/uapi/linux/se_ioctl.h
new file mode 100644
index 000000000000..6302ff66034f
--- /dev/null
+++ b/include/uapi/linux/se_ioctl.h
@@ -0,0 +1,97 @@
+/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause*/
+/*
+ * Copyright 2025 NXP
+ */
+
+#ifndef SE_IOCTL_H
+#define SE_IOCTL_H
+
+#include <linux/types.h>
+
+#define SE_TYPE_STR_DBG			"dbg"
+#define SE_TYPE_STR_HSM			"hsm"
+#define SE_TYPE_ID_UNKWN		0x0
+#define SE_TYPE_ID_DBG			0x1
+#define SE_TYPE_ID_HSM			0x2
+/* IOCTL definitions. */
+
+struct se_ioctl_setup_iobuf {
+	__u64 user_buf;
+	__u32 length;
+	__u32 flags;
+	__u64 ele_addr;
+};
+
+struct se_ioctl_shared_mem_cfg {
+	__u32 base_offset;
+	__u32 size;
+};
+
+struct se_ioctl_get_if_info {
+	__u8 se_if_id;
+	__u8 interrupt_idx;
+	__u8 tz;
+	__u8 did;
+	__u8 cmd_tag;
+	__u8 rsp_tag;
+	__u8 success_tag;
+	__u8 base_api_ver;
+	__u8 fw_api_ver;
+};
+
+struct se_ioctl_cmd_snd_rcv_rsp_info {
+	__u64 tx_buf;
+	__u64 rx_buf;
+	__u32 tx_buf_sz;
+	__u32 rx_buf_sz;
+};
+
+struct se_ioctl_get_soc_info {
+	__u16 soc_id;
+	__u16 soc_rev;
+};
+
+/* IO Buffer Flags */
+#define SE_IO_BUF_FLAGS_IS_OUTPUT	(0x00u)
+#define SE_IO_BUF_FLAGS_IS_INPUT	(0x01u)
+#define SE_IO_BUF_FLAGS_USE_SEC_MEM	(0x02u)
+#define SE_IO_BUF_FLAGS_USE_SHORT_ADDR	(0x04u)
+#define SE_IO_BUF_FLAGS_IS_IN_OUT	(0x10u)
+
+/* IOCTLS */
+#define SE_IOCTL			0x0A /* like MISC_MAJOR. */
+
+/*
+ * ioctl to designated the current fd as logical-reciever.
+ * This is ioctl is send when the nvm-daemon, a slave to the
+ * firmware is started by the user.
+ */
+#define SE_IOCTL_ENABLE_CMD_RCV	_IO(SE_IOCTL, 0x01)
+
+/*
+ * ioctl to get the buffer allocated from the memory, which is shared
+ * between kernel and FW.
+ * Post allocation, the kernel tagged the allocated memory with:
+ *  Output
+ *  Input
+ *  Input-Output
+ *  Short address
+ *  Secure-memory
+ */
+#define SE_IOCTL_SETUP_IOBUF	_IOWR(SE_IOCTL, 0x03, struct se_ioctl_setup_iobuf)
+
+/*
+ * ioctl to get the mu information, that is used to exchange message
+ * with FW, from user-spaced.
+ */
+#define SE_IOCTL_GET_MU_INFO	_IOR(SE_IOCTL, 0x04, struct se_ioctl_get_if_info)
+/*
+ * ioctl to get SoC Info from user-space.
+ */
+#define SE_IOCTL_GET_SOC_INFO      _IOR(SE_IOCTL, 0x06, struct se_ioctl_get_soc_info)
+
+/*
+ * ioctl to send command and receive response from user-space.
+ */
+#define SE_IOCTL_CMD_SEND_RCV_RSP _IOWR(SE_IOCTL, 0x07, struct se_ioctl_cmd_snd_rcv_rsp_info)
+#endif

-- 
2.43.0

Re: [PATCH v34 5/7] firmware: imx: adds miscdev

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 5 potential issue(s) to consider:
- [High] Mismatch in API version parameters when sending and validating session/storage close requests, causing the teardown cleanup to unconditionally fail.
- [High] Firmware storage handle is permanently leaked if command receiver registration fails after a successful ELE_STORAGE_OPEN_REQ.
- [High] Missing payload validation allows cross-process session/storage disruption and handle leaks via spoofed close requests.
- [High] Concurrent close() can race with device unbind, leading to a use-after-free of mailbox channels in mbox_send_message because se_close_session bypasses the going_away safeguard.
- [Medium] Discarding successful firmware responses on interrupted wait causes firmware resource leaks.
--

--- Patch [5]: [PATCH v34 5/7] firmware: imx: adds miscdev ---
commit 4fe94a5b9918db6ab33badde78a9ca4fc596c70c
Author: Pankaj Gupta <pankaj.gupta@nxp.com>
Subject: firmware: imx: adds miscdev

Adds the driver for communication interface to secure-enclave, that enables
exchanging messages with NXP secure enclave HW IP(s). Includes command
validation, session tracking, and teardown management.

Link: https://lore.kernel.org/r/20260805-imx-se-if-v33-0-212e32ff0295@nxp.com

> diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
> --- a/drivers/firmware/imx/ele_common.c
> +++ b/drivers/firmware/imx/ele_common.c
[ ... ]
> @@ -288,6 +288,14 @@ int ele_msg_send_rcv(struct se_if_device_ctx *dev_ctx, void *tx_msg,
>  	if (priv->waiting_rsp_clbk_hdl.signal_rcvd) {
>  		/*
>  		 * Signal was deferred until the FW/kernel protocol resynchronized.
>  		 * On success report -ERESTARTSYS for the interrupted wait; the
>  		 * command is not re-sent. Keep real errors like -ETIMEDOUT.
>  		 */
>  		if (err > 0)
>  			err = -ERESTARTSYS;

[Severity: Medium]
Is it possible this discards a successful firmware response?

In ele_msg_send_rcv(), if a signal interrupted the wait but the firmware
successfully processed a request (like ELE_SESSION_OPEN_REQ), err is
converted to -ERESTARTSYS. This causes se_ioctl_cmd_snd_rcv_rsp_handler()
to return -EINTR without calling fw_api_specific_ops(). As a result, the
successfully allocated session handle is never recorded by the kernel and
gets leaked permanently in the firmware.

> diff --git a/drivers/firmware/imx/ele_fw_api.c b/drivers/firmware/imx/ele_fw_api.c
> --- /dev/null
> +++ b/drivers/firmware/imx/ele_fw_api.c
[ ... ]
> @@ -46,6 +46,10 @@ int ele_uapi_allowed_fw_cmd(struct se_if_device_ctx *dev_ctx, struct se_msg_hdr
>  	case ELE_SESSION_CLOSE_REQ:
>  		/* Might be cleared as part of tear down. */
>  		ret = dev_ctx->sess_hdl ? 0 : -ENXIO;
>  		break;

[Severity: High]
Does this validation allow one process to close another process's handle?

In ele_uapi_allowed_fw_cmd(), the code only verifies that the calling
context has some handle open (dev_ctx->sess_hdl is non-zero). It does not
check if the handle ID provided in the user's payload (tx_msg->data[0])
actually matches the context's dev_ctx->sess_hdl. A malicious user with one
valid handle could send a spoofed close request with another process's handle
ID, disrupting the victim and leaking their own handle.

[ ... ]
> @@ -79,15 +83,16 @@ void fw_api_specific_ops(struct se_if_device_ctx *dev_ctx, struct se_api_msg *rx
>  	case ELE_STORAGE_OPEN_REQ: {
>  		int rc = 0;
>  
>  		rc = set_dev_ctx_as_command_receiver(dev_ctx);
>  		if (rc) {
>  			dev_err(priv->dev,
>  				"Failed to register %s as CMD-Receiver: %d\n",
>  				dev_ctx->devname, rc);
>  			break;
>  		}
>  		dev_ctx->strg_hdl = rx_msg->data[1];
>  		break;
>  	}

[Severity: High]
Can this leak a newly opened storage handle on registration failure?

If set_dev_ctx_as_command_receiver() fails (e.g. returning -EBUSY because a
receiver is already registered), the code breaks early and skips assigning
rx_msg->data[1] to dev_ctx->strg_hdl. Because the ioctl still returns success
to userspace and dev_ctx->strg_hdl remains 0, the kernel will not track the
handle for teardown, resulting in a permanent firmware resource leak.

[ ... ]
> @@ -113,19 +118,22 @@ int se_close_session(struct se_if_priv *priv, u32 session_hdl)
>  
>  	se_fill_cmd_msg_hdr(priv, (struct se_msg_hdr *)&tx_msg->header,
>  			    ELE_SESSION_CLOSE_REQ, ELE_SESSION_CLOSE_REQ_SZ, true);
>  
>  	tx_msg->data[0] = session_hdl;
>  
>  	ret = ele_msg_send_rcv(priv->priv_dev_ctx,
>  			       tx_msg,
>  			       ELE_SESSION_CLOSE_REQ_SZ,
>  			       rx_msg,
>  			       ELE_SESSION_CLOSE_RSP_SZ);

[Severity: High]
Could this cause a use-after-free of mailbox channels during device unbind?

By hardcoding priv->priv_dev_ctx here instead of using the user's actual
device context, this unconditionally bypasses the teardown safeguard in
ele_msg_send_rcv() (which allows priv_dev_ctx teardown messages through).
If a user calls close() concurrently with driver unbind, and the unbind
thread frees priv->tx_chan, the concurrent close() thread will skip the
going_away check and attempt a transmission on the freed channel.

>  	if (ret < 0)
>  		return ret;
>  
>  	ret = se_val_rsp_hdr_n_status(priv,
>  				      rx_msg,
>  				      ELE_SESSION_CLOSE_REQ,
>  				      ELE_SESSION_CLOSE_RSP_SZ,
>  				      false);
>  	return ret;
>  }

[Severity: High]
Is there a version mismatch causing cleanup to unconditionally fail?

When formatting the request earlier in se_close_session(),
se_fill_cmd_msg_hdr() is called with is_base_api = true. But here,
se_val_rsp_hdr_n_status() is called with is_base_api = false, which strictly
expects the response version to match fw_api_ver. This mismatch causes
validation to fail with -EINVAL, leaking firmware resources since the kernel
considers the close operation to have failed. This identical mismatch also
exists in se_close_storage().

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-imx-se-if-v34-0-7e4713d14e0a@nxp.com?part=5

[PATCH v34 6/7] arm64: dts: imx8ulp: add secure enclave node

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Add the EdgeLock Enclave (ELE) secure-enclave node to the i.MX8ULP SoC
dtsi, together with a label for sram@2201f000 that the node references.

Keep the node disabled in the SoC dtsi so it does not impose a
reserved-memory requirement on every board. Boards enable the enclave and
provide its memory-region by including imx8ulp-firmware.dtsi.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8ulp.dtsi | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
index c6d1bb9edf38..38233dd74ee3 100644
--- a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
 /*
- * Copyright 2021 NXP
+ * Copyright 2021, 2025 NXP
  */
 
 #include <dt-bindings/clock/imx8ulp-clock.h>
@@ -153,7 +153,7 @@ sosc: clock-sosc {
 		#clock-cells = <0>;
 	};
 
-	sram@2201f000 {
+	sram0: sram@2201f000 {
 		compatible = "mmio-sram";
 		reg = <0x0 0x2201f000 0x0 0x1000>;
 
@@ -185,6 +185,14 @@ scmi_sensor: protocol@15 {
 				#thermal-sensor-cells = <1>;
 			};
 		};
+
+		hsm0: secure-enclave {
+			compatible = "fsl,imx8ulp-se-ele-hsm";
+			mbox-names = "tx", "rx";
+			mboxes = <&s4muap 0 0>, <&s4muap 1 0>;
+			sram = <&sram0>;
+			status = "disabled";
+		};
 	};
 
 	cm33: remoteproc-cm33 {

-- 
2.43.0

Re: [PATCH v34 6/7] arm64: dts: imx8ulp: add secure enclave node

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing strictly required property `memory-region` in the disabled `secure-enclave` node will trigger `dt-validate` schema errors.
--

--- Patch [6]: [PATCH v34 6/7] arm64: dts: imx8ulp: add secure enclave node ---
commit 0fca804b5890d1b30a2a6c7de7313c46555323fc
Author: Pankaj Gupta <pankaj.gupta@nxp.com>

arm64: dts: imx8ulp: add secure enclave node

Add the EdgeLock Enclave (ELE) secure-enclave node to the i.MX8ULP SoC dtsi.
The node is kept disabled so it does not impose a reserved-memory requirement
on every board.

> diff --git a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
> index c6d1bb9edf388..38233dd74ee33 100644
> --- a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi

[ ... ]

> @@ -185,6 +185,14 @@ scmi_sensor: protocol@15 {
>  				#thermal-sensor-cells = <1>;
>  			};
>  		};
> +
> +		hsm0: secure-enclave {
> +			compatible = "fsl,imx8ulp-se-ele-hsm";
> +			mbox-names = "tx", "rx";
> +			mboxes = <&s4muap 0 0>, <&s4muap 1 0>;
> +			sram = <&sram0>;
> +			status = "disabled";
> +		};

[Severity: Medium]
Will this node definition trigger dt-validate schema errors during make
dtbs_check?

Looking at Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml, the
schema unconditionally requires the memory-region property for this compatible:

  - if:
      properties:
        compatible:
          contains:
            enum:
              - fsl,imx8ulp-se-ele-hsm
              - fsl,imx93-se-ele-hsm
    then:
      required:
        - memory-region

Since dt-validate checks all nodes regardless of their status = "disabled"
property, omitting memory-region here means any board devicetree that includes
imx8ulp.dtsi but leaves this node disabled will fail validation.

>  	};
>  
>  	cm33: remoteproc-cm33 {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-imx-se-if-v34-0-7e4713d14e0a@nxp.com?part=6

[PATCH v34 7/7] arm64: dts: imx8ulp: add reserved memory for EdgeLock Enclave

[pankaj.gupta]

From: Pankaj Gupta <pankaj.gupta@nxp.com>

Reserve 1MB of DDR for the EdgeLock Enclave. The enclave hardware can only
access DDR in the 0x80000000 - 0xafffffff window, so constrain the pool to
that range with alloc-ranges and let the kernel choose the placement rather
than hardcoding an address.

Provide this as a shared imx8ulp-firmware.dtsi that also enables the hsm0
node and wires up its memory-region, so every i.MX8ULP board can bring up
the enclave with a single include instead of duplicating the reserved
memory node. Include it from imx8ulp-evk.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8ulp-evk.dts      |  3 ++-
 .../arm64/boot/dts/freescale/imx8ulp-firmware.dtsi | 31 ++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts b/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts
index 5dea66c1e7aa..885242fd07ce 100644
--- a/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts
@@ -1,11 +1,12 @@
 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
 /*
- * Copyright 2021 NXP
+ * Copyright 2021, 2025 NXP
  */
 
 /dts-v1/;
 
 #include "imx8ulp.dtsi"
+#include "imx8ulp-firmware.dtsi"
 
 / {
 	model = "NXP i.MX8ULP EVK";
diff --git a/arch/arm64/boot/dts/freescale/imx8ulp-firmware.dtsi b/arch/arm64/boot/dts/freescale/imx8ulp-firmware.dtsi
new file mode 100644
index 000000000000..e4bc352f68af
--- /dev/null
+++ b/arch/arm64/boot/dts/freescale/imx8ulp-firmware.dtsi
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2025 NXP
+ *
+ * Default reserved memory and EdgeLock Enclave (ELE) enablement shared by
+ * i.MX8ULP boards. Include this from a board dts to bring up the secure
+ * enclave without having to duplicate the reserved-memory node. The ELE
+ * hardware can only access DDR in the 0x80000000 - 0xafffffff window, so the
+ * pool is constrained to that range with alloc-ranges and the kernel is left
+ * to place the 1 MiB region.
+ */
+
+/ {
+	reserved-memory {
+		#address-cells = <2>;
+		#size-cells = <2>;
+		ranges;
+
+		ele_reserved: ele-reserved {
+			compatible = "shared-dma-pool";
+			alloc-ranges = <0 0x80000000 0 0x30000000>;
+			size = <0 0x100000>;
+			no-map;
+		};
+	};
+};
+
+&hsm0 {
+	memory-region = <&ele_reserved>;
+	status = "okay";
+};

-- 
2.43.0