[PATCH v3 5/5] firmware: imx: adds miscdev

Pankaj Gupta
2024-06-17T07:33:17Z

Adds the driver for communication interface to secure-enclave,
for 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

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
---
Documentation/ABI/testing/se-cdev | 42 +++
drivers/firmware/imx/ele_common.c | 153 ++++++++-
drivers/firmware/imx/ele_common.h | 4 +
drivers/firmware/imx/se_ctrl.c | 694 ++++++++++++++++++++++++++++++++++++++
drivers/firmware/imx/se_ctrl.h | 49 +++
include/uapi/linux/se_ioctl.h | 94 ++++++
6 files changed, 1034 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/se-cdev b/Documentation/ABI/testing/se-cdev
new file mode 100644
index 000000000000..699525af6b86
--- /dev/null
+++ b/Documentation/ABI/testing/se-cdev
@@ -0,0 +1,42 @@
+What: /dev/<se>_mu[0-9]+_ch[0-9]+
+Date: May 2024
+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 user-space 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
+ - get mu info
+ - setting a dev-ctx as receiver that is slave to fw
+ - get SoC info
+
+ 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
+ wakeup_intruptible, 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 free up the I/O contexts that was 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/ele_common.c b/drivers/firmware/imx/ele_common.c
index 0139748f7150..3d608a851962 100644
--- a/drivers/firmware/imx/ele_common.c
+++ b/drivers/firmware/imx/ele_common.c
@@ -78,12 +78,146 @@ int imx_ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, void *rx_msg)
return err;
}

+int imx_ele_miscdev_msg_rcv(struct se_if_device_ctx *dev_ctx,
+ void *rx_buf,
+ int rx_buf_sz)
+{
+ struct se_msg_hdr *header;
+ u32 size_to_copy;
+ int err;
+
+ err = wait_event_interruptible(dev_ctx->wq, dev_ctx->pending_hdr != 0);
+ if (err)
+ dev_err(dev_ctx->dev,
+ "%s: Err[0x%x]:Interrupted by signal.\n",
+ dev_ctx->miscdev.name, err);
+
+ header = (struct se_msg_hdr *) dev_ctx->temp_resp;
+
+ if (header->tag == dev_ctx->priv->rsp_tag) {
+ if (dev_ctx->priv->waiting_rsp_dev != dev_ctx) {
+ dev_warn(dev_ctx->dev,
+ "%s: Device context waiting for response mismatch.\n",
+ dev_ctx->miscdev.name);
+ err = -EPERM;
+ }
+ }
+
+ dev_dbg(dev_ctx->dev,
+ "%s: %s %s\n",
+ dev_ctx->miscdev.name,
+ __func__,
+ "message received, start transmit to user");
+
+ /*
+ * Check that the size passed as argument is larger than
+ * the one carried in the message.
+ */
+ size_to_copy = dev_ctx->temp_resp_size << 2;
+ if (size_to_copy > rx_buf_sz) {
+ dev_dbg(dev_ctx->dev,
+ "%s: User buffer too small (%d < %d)\n",
+ dev_ctx->miscdev.name,
+ rx_buf_sz, size_to_copy);
+ size_to_copy = rx_buf_sz;
+ }
+
+ /* 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)
+ goto exit;
+
+ /* Copy data from the buffer */
+ print_hex_dump_debug("to user ", DUMP_PREFIX_OFFSET, 4, 4,
+ dev_ctx->temp_resp, size_to_copy, false);
+ if (copy_to_user(rx_buf, dev_ctx->temp_resp, size_to_copy)) {
+ dev_err(dev_ctx->dev,
+ "%s: Failed to copy to user\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+ err = size_to_copy;
+exit:
+
+ /* free memory allocated on the shared buffers. */
+ dev_ctx->secure_mem.pos = 0;
+ dev_ctx->non_secure_mem.pos = 0;
+
+ dev_ctx->pending_hdr = 0;
+ se_dev_ctx_shared_mem_cleanup(dev_ctx);
+
+ return err;
+}
+
+int imx_ele_miscdev_msg_send(struct se_if_device_ctx *dev_ctx,
+ void *tx_msg, int tx_msg_sz)
+{
+ struct se_if_priv *priv = dev_ctx->priv;
+ struct se_msg_hdr *header;
+ u32 size_to_send;
+ int err;
+
+ header = (struct se_msg_hdr *) tx_msg;
+
+ /*
+ * Check that the size passed as argument matches the size
+ * carried in the message.
+ */
+ size_to_send = header->size << 2;
+
+ if (size_to_send != tx_msg_sz) {
+ err = -EINVAL;
+ dev_err(priv->dev,
+ "%s: User buffer header size mismatced with input size.\n",
+ dev_ctx->miscdev.name);
+ goto exit;
+ }
+ /* Check the message is valid according to tags */
+ if (header->tag == priv->rsp_tag) {
+ /* Check the device context can send the command */
+ if (dev_ctx != priv->cmd_receiver_dev) {
+ dev_err(priv->dev,
+ "%s: Channel not configured to send resp to FW.",
+ dev_ctx->miscdev.name);
+ err = -EPERM;
+ goto exit;
+ }
+ } else if (header->tag == priv->cmd_tag) {
+ if (priv->waiting_rsp_dev != dev_ctx) {
+ dev_err(priv->dev,
+ "%s: Channel not configured to send cmd to FW.",
+ dev_ctx->miscdev.name);
+ err = -EPERM;
+ goto exit;
+ }
+ lockdep_assert_held(&priv->se_if_cmd_lock);
+ } else {
+ dev_err(priv->dev,
+ "%s: The message does not have a valid TAG\n",
+ dev_ctx->miscdev.name);
+ err = -EINVAL;
+ goto exit;
+ }
+ err = imx_ele_msg_send(priv, tx_msg);
+ if (err < 0)
+ goto exit;
+
+ err = size_to_send;
+exit:
+ return err;
+}
+
/*
* Callback called by mailbox FW, when data is received.
*/
void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
{
struct device *dev = mbox_cl->dev;
+ struct se_if_device_ctx *dev_ctx;
struct se_if_priv *priv;
struct se_msg_hdr *header;

@@ -97,8 +231,15 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)

header = (struct se_msg_hdr *) msg;

- if (header->tag == priv->rsp_tag) {
- if (!priv->waiting_rsp_dev) {
+ /* Incoming command: wake up the receiver if any. */
+ if (header->tag == priv->cmd_tag) {
+ dev_dbg(dev, "Selecting cmd receiver\n");
+ dev_ctx = priv->cmd_receiver_dev;
+ } else if (header->tag == priv->rsp_tag) {
+ if (priv->waiting_rsp_dev) {
+ dev_dbg(dev, "Selecting rsp waiter\n");
+ dev_ctx = priv->waiting_rsp_dev;
+ } else {
/*
* Reading the EdgeLock Enclave response
* to the command, sent by other
@@ -116,6 +257,14 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
*((u32 *) header));
return;
}
+ /* Init reception */
+ memcpy(dev_ctx->temp_resp, msg, header->size << 2);
+
+ dev_ctx->temp_resp_size = header->size;
+
+ /* Allow user to read */
+ dev_ctx->pending_hdr = 1;
+ wake_up_interruptible(&dev_ctx->wq);
}

int validate_rsp_hdr(struct se_if_priv *priv,
diff --git a/drivers/firmware/imx/ele_common.h b/drivers/firmware/imx/ele_common.h
index 24569ad29a1f..ea443a9f7ad0 100644
--- a/drivers/firmware/imx/ele_common.h
+++ b/drivers/firmware/imx/ele_common.h
@@ -14,6 +14,10 @@
#define IMX_ELE_FW_DIR "imx/ele/"

uint32_t imx_se_add_msg_crc(uint32_t *msg, uint32_t msg_len);
+int imx_ele_miscdev_msg_rcv(struct se_if_device_ctx *dev_ctx,
+ void *rx_msg, int rx_msg_sz);
+int imx_ele_miscdev_msg_send(struct se_if_device_ctx *dev_ctx,
+ void *tx_msg, int tx_msg_sz);
int imx_ele_msg_rcv(struct se_if_priv *priv);
int imx_ele_msg_send(struct se_if_priv *priv, void *tx_msg);
int imx_ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, void *rx_msg);
diff --git a/drivers/firmware/imx/se_ctrl.c b/drivers/firmware/imx/se_ctrl.c
index a7a7cacb4416..c018a4f728d0 100644
--- a/drivers/firmware/imx/se_ctrl.c
+++ b/drivers/firmware/imx/se_ctrl.c
@@ -23,6 +23,7 @@
#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"
@@ -236,6 +237,605 @@ static int imx_fetch_se_soc_info(struct se_if_priv *priv,
return 0;
}

+static int se_ioctl_cmd_snd_rcv_rsp_handler(struct se_if_device_ctx *dev_ctx,
+ u64 arg)
+{
+ struct se_if_priv *priv = dev_get_drvdata(dev_ctx->dev);
+ struct se_ioctl_cmd_snd_rcv_rsp_info cmd_snd_rcv_rsp_info;
+ struct se_api_msg *tx_msg __free(kfree) = NULL;
+ struct se_api_msg *rx_msg __free(kfree) = NULL;
+ int err = 0;
+
+ if (copy_from_user(&cmd_snd_rcv_rsp_info, (u8 *)arg,
+ sizeof(struct se_ioctl_cmd_snd_rcv_rsp_info))) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed to copy cmd_snd_rcv_rsp_info from user\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+ if (cmd_snd_rcv_rsp_info.tx_buf_sz < SE_MU_HDR_SZ) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: User buffer too small(%d < %d)\n",
+ dev_ctx->miscdev.name,
+ cmd_snd_rcv_rsp_info.tx_buf_sz,
+ SE_MU_HDR_SZ);
+ err = -ENOSPC;
+ goto exit;
+ }
+
+ rx_msg = kzalloc(cmd_snd_rcv_rsp_info.rx_buf_sz, GFP_KERNEL);
+ if (!rx_msg) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ tx_msg = memdup_user(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);
+ goto exit;
+ }
+
+ if (tx_msg->header.tag != priv->cmd_tag) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ scoped_guard(mutex, &priv->se_if_cmd_lock);
+ priv->waiting_rsp_dev = dev_ctx;
+
+ /* Device Context that is assigned to be a
+ * FW's command receiver, has pre-allocated buffer.
+ */
+ if (dev_ctx != priv->cmd_receiver_dev)
+ dev_ctx->temp_resp = rx_msg;
+
+ err = imx_ele_miscdev_msg_send(dev_ctx,
+ tx_msg,
+ cmd_snd_rcv_rsp_info.tx_buf_sz);
+ cmd_snd_rcv_rsp_info.tx_buf_sz = err;
+ if (err < 0)
+ goto exit;
+
+ err = imx_ele_miscdev_msg_rcv(dev_ctx,
+ cmd_snd_rcv_rsp_info.rx_buf,
+ cmd_snd_rcv_rsp_info.rx_buf_sz);
+
+ cmd_snd_rcv_rsp_info.rx_buf_sz = err;
+ priv->waiting_rsp_dev = NULL;
+ if (dev_ctx != priv->cmd_receiver_dev)
+ dev_ctx->temp_resp = NULL;
+
+exit:
+ if (copy_to_user((void *)arg, &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 from user\n",
+ dev_ctx->miscdev.name);
+ 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_api_msg *tx_msg __free(kfree) = NULL;
+ struct se_if_device_ctx *dev_ctx;
+ struct se_if_priv *priv;
+ int err;
+
+ dev_ctx = container_of(fp->private_data,
+ struct se_if_device_ctx,
+ miscdev);
+ priv = dev_ctx->priv;
+ dev_dbg(priv->dev,
+ "%s: write from buf (%p)%zu, ppos=%lld\n",
+ dev_ctx->miscdev.name,
+ buf, size, ((ppos) ? *ppos : 0));
+
+ if (down_interruptible(&dev_ctx->fops_lock))
+ return -EBUSY;
+
+ if (dev_ctx->status != SE_IF_CTX_OPENED) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ if (size < SE_MU_HDR_SZ) {
+ dev_err(priv->dev,
+ "%s: User buffer too small(%zu < %d)\n",
+ dev_ctx->miscdev.name,
+ size, SE_MU_HDR_SZ);
+ err = -ENOSPC;
+ goto exit;
+ }
+ tx_msg = memdup_user(buf, size);
+ if (IS_ERR(tx_msg)) {
+ err = PTR_ERR(tx_msg);
+ goto exit;
+ }
+
+ print_hex_dump_debug("from user ", DUMP_PREFIX_OFFSET, 4, 4,
+ tx_msg, size, false);
+
+ err = imx_ele_miscdev_msg_send(dev_ctx, tx_msg, size);
+
+exit:
+ up(&dev_ctx->fops_lock);
+ 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;
+ struct se_if_priv *priv;
+ int err;
+
+ dev_ctx = container_of(fp->private_data,
+ struct se_if_device_ctx,
+ miscdev);
+ priv = dev_ctx->priv;
+ dev_dbg(priv->dev,
+ "%s: read to buf %p(%zu), ppos=%lld\n",
+ dev_ctx->miscdev.name,
+ buf, size, ((ppos) ? *ppos : 0));
+
+ if (down_interruptible(&dev_ctx->fops_lock))
+ return -EBUSY;
+
+ if (dev_ctx->status != SE_IF_CTX_OPENED) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ err = imx_ele_miscdev_msg_rcv(dev_ctx, buf, size);
+
+exit:
+ up(&dev_ctx->fops_lock);
+ return err;
+}
+
+static int se_ioctl_get_mu_info(struct se_if_device_ctx *dev_ctx,
+ u64 arg)
+{
+ struct se_if_priv *priv = dev_get_drvdata(dev_ctx->dev);
+ struct imx_se_node_info *if_node_info;
+ struct se_ioctl_get_if_info info;
+ int err = 0;
+
+ if_node_info = (struct imx_se_node_info *)priv->info;
+
+ info.se_if_id = if_node_info->se_if_id;
+ info.interrupt_idx = 0;
+ info.tz = 0;
+ info.did = if_node_info->se_if_did;
+ info.cmd_tag = if_node_info->cmd_tag;
+ info.rsp_tag = if_node_info->rsp_tag;
+ info.success_tag = if_node_info->success_tag;
+ info.base_api_ver = if_node_info->base_api_ver;
+ info.fw_api_ver = if_node_info->fw_api_ver;
+
+ dev_dbg(priv->dev,
+ "%s: info [se_if_id: %d, irq_idx: %d, tz: 0x%x, did: 0x%x]\n",
+ dev_ctx->miscdev.name,
+ info.se_if_id, info.interrupt_idx, info.tz, info.did);
+
+ if (copy_to_user((u8 *)arg, &info, sizeof(info))) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed to copy mu info to user\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+exit:
+ return err;
+}
+
+/* Need to copy the output data to user-device context.
+ */
+int se_dev_ctx_cpy_out_data(struct se_if_device_ctx *dev_ctx)
+{
+ struct se_buf_desc *b_desc, *temp;
+
+ list_for_each_entry_safe(b_desc, temp, &dev_ctx->pending_out, link) {
+ if (b_desc->usr_buf_ptr && b_desc->shared_buf_ptr) {
+
+ dev_dbg(dev_ctx->dev,
+ "%s: Copy output data to user\n",
+ dev_ctx->miscdev.name);
+ if (copy_to_user(b_desc->usr_buf_ptr,
+ b_desc->shared_buf_ptr,
+ b_desc->size)) {
+ dev_err(dev_ctx->dev,
+ "%s: Failure copying output data to user.",
+ dev_ctx->miscdev.name);
+ return -EFAULT;
+ }
+ }
+
+ 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 0;
+}
+
+/*
+ * 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 list_head *dev_ctx_lists[] = {&dev_ctx->pending_in,
+ &dev_ctx->pending_out};
+ struct se_buf_desc *b_desc, *temp;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ list_for_each_entry_safe(b_desc, temp,
+ dev_ctx_lists[i], link) {
+
+ if (!b_desc)
+ continue;
+
+ if (b_desc->shared_buf_ptr)
+ memset(b_desc->shared_buf_ptr, 0, b_desc->size);
+
+ list_del(&b_desc->link);
+ kfree(b_desc);
+ }
+ }
+}
+
+/*
+ * 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,
+ u64 arg)
+{
+ struct se_shared_mem *shared_mem = NULL;
+ struct se_ioctl_setup_iobuf io = {0};
+ struct se_buf_desc *b_desc = NULL;
+ int err = 0;
+ u32 pos;
+
+ if (copy_from_user(&io, (u8 *)arg, sizeof(io))) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed copy iobuf config from user\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+ dev_dbg(dev_ctx->priv->dev,
+ "%s: io [buf: %p(%d) flag: %x]\n",
+ dev_ctx->miscdev.name,
+ 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;
+ }
+
+ /* Select the shared memory to be used for this buffer. */
+ if (io.flags & SE_MU_IO_FLAGS_USE_SEC_MEM) {
+ /* App requires to use secure memory for this buffer.*/
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed allocate SEC MEM memory\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ } else {
+ /* No specific requirement for this buffer. */
+ shared_mem = &dev_ctx->non_secure_mem;
+ }
+
+ /* Check there is enough space in the shared memory. */
+ if (shared_mem->size < shared_mem->pos ||
+ round_up(io.length, 8u) >= (shared_mem->size - shared_mem->pos)) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Not enough space in shared memory\n",
+ dev_ctx->miscdev.name);
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ /* Allocate space in shared memory. 8 bytes aligned. */
+ pos = shared_mem->pos;
+ shared_mem->pos += round_up(io.length, 8u);
+ io.ele_addr = (u64)shared_mem->dma_addr + pos;
+
+ if ((io.flags & SE_MU_IO_FLAGS_USE_SEC_MEM) &&
+ !(io.flags & SE_MU_IO_FLAGS_USE_SHORT_ADDR)) {
+ /*Add base address to get full address.*/
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed allocate SEC MEM memory\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+ memset(shared_mem->ptr + pos, 0, io.length);
+ 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(shared_mem->ptr + pos, io.user_buf,
+ io.length)) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed copy data to shared memory\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+ }
+
+ b_desc = kzalloc(sizeof(*b_desc), GFP_KERNEL);
+ if (!b_desc) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+copy:
+ /* Provide the EdgeLock Enclave address to user space only if success.*/
+ if (copy_to_user((u8 *)arg, &io, sizeof(io))) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed to copy iobuff setup to user\n",
+ dev_ctx->miscdev.name);
+ kfree(b_desc);
+ err = -EFAULT;
+ goto exit;
+ }
+
+ if (b_desc) {
+ b_desc->shared_buf_ptr = shared_mem->ptr + pos;
+ b_desc->usr_buf_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, &dev_ctx->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, &dev_ctx->pending_out);
+ }
+ }
+
+exit:
+ return err;
+}
+
+/* IOCTL to provide SoC information */
+static int se_ioctl_get_se_soc_info_handler(struct se_if_device_ctx *dev_ctx,
+ u64 arg)
+{
+ struct imx_se_node_info_list *info_list;
+ struct se_ioctl_get_soc_info soc_info;
+ int err = -EINVAL;
+
+ info_list = (struct imx_se_node_info_list *)
+ device_get_match_data(dev_ctx->priv->dev);
+ if (!info_list)
+ goto exit;
+
+ soc_info.soc_id = info_list->soc_id;
+ soc_info.soc_rev = dev_ctx->priv->soc_rev;
+
+ err = (int)copy_to_user((u8 *)arg, (u8 *)(&soc_info), sizeof(soc_info));
+ if (err) {
+ dev_err(dev_ctx->priv->dev,
+ "%s: Failed to copy soc info to user\n",
+ dev_ctx->miscdev.name);
+ err = -EFAULT;
+ goto exit;
+ }
+
+exit:
+ return err;
+}
+
+/* Open a character device. */
+static int se_if_fops_open(struct inode *nd, struct file *fp)
+{
+ struct se_if_device_ctx *dev_ctx = container_of(fp->private_data,
+ struct se_if_device_ctx,
+ miscdev);
+ int err = 0;
+
+ /* Avoid race if opened at the same time */
+ if (down_trylock(&dev_ctx->fops_lock))
+ return -EBUSY;
+
+ /* Authorize only 1 instance. */
+ if (dev_ctx->status != SE_IF_CTX_FREE) {
+ err = -EBUSY;
+ goto exit;
+ }
+
+ /*
+ * Allocate some memory for data exchanges with S40x.
+ * This will be used for data not requiring secure memory.
+ */
+ dev_ctx->non_secure_mem.ptr = dmam_alloc_coherent(dev_ctx->dev,
+ MAX_DATA_SIZE_PER_USER,
+ &dev_ctx->non_secure_mem.dma_addr,
+ GFP_KERNEL);
+ if (!dev_ctx->non_secure_mem.ptr) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ dev_ctx->non_secure_mem.size = MAX_DATA_SIZE_PER_USER;
+ dev_ctx->non_secure_mem.pos = 0;
+ dev_ctx->status = SE_IF_CTX_OPENED;
+
+ dev_ctx->pending_hdr = 0;
+
+ goto exit;
+
+ dmam_free_coherent(dev_ctx->priv->dev, MAX_DATA_SIZE_PER_USER,
+ dev_ctx->non_secure_mem.ptr,
+ dev_ctx->non_secure_mem.dma_addr);
+
+exit:
+ up(&dev_ctx->fops_lock);
+ 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 = container_of(fp->private_data,
+ struct se_if_device_ctx,
+ miscdev);
+ struct se_if_priv *priv = dev_ctx->priv;
+
+ /* Avoid race if closed at the same time */
+ if (down_trylock(&dev_ctx->fops_lock))
+ return -EBUSY;
+
+ /* The device context has not been opened */
+ if (dev_ctx->status != SE_IF_CTX_OPENED)
+ goto exit;
+
+ /* check if this device was registered as command receiver. */
+ if (priv->cmd_receiver_dev == dev_ctx) {
+ priv->cmd_receiver_dev = NULL;
+ kfree(dev_ctx->temp_resp);
+ }
+
+ /* check if this device was registered as waiting response. */
+ if (priv->waiting_rsp_dev == dev_ctx) {
+ priv->waiting_rsp_dev = NULL;
+ mutex_unlock(&priv->se_if_cmd_lock);
+ }
+
+ /* Unmap secure memory shared buffer. */
+ if (dev_ctx->secure_mem.ptr)
+ devm_iounmap(dev_ctx->dev, dev_ctx->secure_mem.ptr);
+
+ dev_ctx->secure_mem.ptr = NULL;
+ dev_ctx->secure_mem.dma_addr = 0;
+ dev_ctx->secure_mem.size = 0;
+ dev_ctx->secure_mem.pos = 0;
+
+ /* Free non-secure shared buffer. */
+ dmam_free_coherent(dev_ctx->priv->dev, MAX_DATA_SIZE_PER_USER,
+ dev_ctx->non_secure_mem.ptr,
+ dev_ctx->non_secure_mem.dma_addr);
+
+ dev_ctx->non_secure_mem.ptr = NULL;
+ dev_ctx->non_secure_mem.dma_addr = 0;
+ dev_ctx->non_secure_mem.size = 0;
+ dev_ctx->non_secure_mem.pos = 0;
+ se_dev_ctx_shared_mem_cleanup(dev_ctx);
+ dev_ctx->status = SE_IF_CTX_FREE;
+
+exit:
+ up(&dev_ctx->fops_lock);
+ 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 = container_of(fp->private_data,
+ struct se_if_device_ctx,
+ miscdev);
+ struct se_if_priv *se_if_priv = dev_ctx->priv;
+ int err = -EINVAL;
+
+ /* Prevent race during change of device context */
+ if (down_interruptible(&dev_ctx->fops_lock))
+ return -EBUSY;
+
+ switch (cmd) {
+ case SE_IOCTL_ENABLE_CMD_RCV:
+ if (!se_if_priv->cmd_receiver_dev) {
+ err = 0;
+ se_if_priv->cmd_receiver_dev = dev_ctx;
+ dev_ctx->temp_resp = kzalloc(MAX_NVM_MSG_LEN, GFP_KERNEL);
+ if (!dev_ctx->temp_resp)
+ err = -ENOMEM;
+ }
+ break;
+ case SE_IOCTL_GET_MU_INFO:
+ err = se_ioctl_get_mu_info(dev_ctx, arg);
+ break;
+ case SE_IOCTL_SETUP_IOBUF:
+ err = se_ioctl_setup_iobuf_handler(dev_ctx, arg);
+ break;
+ case SE_IOCTL_GET_SOC_INFO:
+ err = se_ioctl_get_se_soc_info_handler(dev_ctx, arg);
+ break;
+ case SE_IOCTL_CMD_SEND_RCV_RSP:
+ err = se_ioctl_cmd_snd_rcv_rsp_handler(dev_ctx, arg);
+ break;
+
+ default:
+ err = -EINVAL;
+ dev_dbg(se_if_priv->dev,
+ "%s: IOCTL %.8x not supported\n",
+ dev_ctx->miscdev.name,
+ cmd);
+ }
+
+ up(&dev_ctx->fops_lock);
+ return (long)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,
+ .read = se_if_fops_read,
+ .write = se_if_fops_write,
+};
+
+/* interface for managed res to unregister a character device */
+static void if_misc_deregister(void *miscdevice)
+{
+ misc_deregister(miscdevice);
+}
+
/* interface for managed res to free a mailbox channel */
static void if_mbox_free_channel(void *mbox_chan)
{
@@ -274,6 +874,7 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct se_if_priv *priv;
int ret = 0;
+ int i;

priv = dev_get_drvdata(dev);

@@ -293,6 +894,17 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
priv->imem.buf = NULL;
}

+ if (priv->ctxs) {
+ for (i = 0; i < priv->max_dev_ctx; i++) {
+ if (priv->ctxs[i]) {
+ devm_remove_action(dev,
+ if_misc_deregister,
+ &priv->ctxs[i]->miscdev);
+ misc_deregister(&priv->ctxs[i]->miscdev);
+ }
+ }
+ }
+
/* No need to check, if reserved memory is allocated
* before calling for its release. Or clearing the
* un-set bit.
@@ -303,6 +915,74 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
return ret;
}

+static int init_device_context(struct se_if_priv *priv)
+{
+ const struct imx_se_node_info *info = priv->info;
+ struct se_if_device_ctx *dev_ctx;
+ u8 *devname;
+ int ret = 0;
+ int i;
+
+ priv->ctxs = devm_kzalloc(priv->dev, sizeof(dev_ctx) * priv->max_dev_ctx,
+ GFP_KERNEL);
+
+ if (!priv->ctxs) {
+ ret = -ENOMEM;
+ return ret;
+ }
+
+ /* Create users */
+ for (i = 0; i < priv->max_dev_ctx; i++) {
+ dev_ctx = devm_kzalloc(priv->dev, sizeof(*dev_ctx), GFP_KERNEL);
+ if (!dev_ctx) {
+ ret = -ENOMEM;
+ return ret;
+ }
+
+ dev_ctx->dev = priv->dev;
+ dev_ctx->status = SE_IF_CTX_FREE;
+ dev_ctx->priv = priv;
+
+ priv->ctxs[i] = dev_ctx;
+
+ /* Default value invalid for an header. */
+ init_waitqueue_head(&dev_ctx->wq);
+
+ INIT_LIST_HEAD(&dev_ctx->pending_out);
+ INIT_LIST_HEAD(&dev_ctx->pending_in);
+ sema_init(&dev_ctx->fops_lock, 1);
+
+ devname = devm_kasprintf(priv->dev, GFP_KERNEL, "%s_ch%d",
+ info->se_name, i);
+ if (!devname) {
+ ret = -ENOMEM;
+ return ret;
+ }
+
+ dev_ctx->miscdev.name = devname;
+ dev_ctx->miscdev.minor = MISC_DYNAMIC_MINOR;
+ dev_ctx->miscdev.fops = &se_if_fops;
+ dev_ctx->miscdev.parent = priv->dev;
+ ret = misc_register(&dev_ctx->miscdev);
+ if (ret) {
+ dev_err(priv->dev, "failed to register misc device %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = devm_add_action(priv->dev, if_misc_deregister,
+ &dev_ctx->miscdev);
+ if (ret) {
+ dev_err(priv->dev,
+ "failed[%d] to add action to the misc-dev\n",
+ ret);
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
static void se_load_firmware(const struct firmware *fw, void *context)
{
struct se_if_priv *priv = (struct se_if_priv *) context;
@@ -463,6 +1143,16 @@ static int se_if_probe(struct platform_device *pdev)
ret = 0;
}

+ if (info->max_dev_ctx) {
+ ret = init_device_context(priv);
+ if (ret) {
+ dev_err(dev,
+ "Failed[0x%x] to create device contexts.\n",
+ ret);
+ goto exit;
+ }
+ }
+
dev_info(dev, "i.MX secure-enclave: %s interface to firmware, configured.\n",
info->se_name);
return ret;
@@ -507,6 +1197,10 @@ static int se_resume(struct device *dev)
{
struct se_if_priv *priv = dev_get_drvdata(dev);
const struct imx_se_node_info *info = priv->info;
+ int i;
+
+ for (i = 0; i < priv->max_dev_ctx; i++)
+ wake_up_interruptible(&priv->ctxs[i]->wq);

if (info && info->imem_mgmt)
se_restore_imem_state(priv);
diff --git a/drivers/firmware/imx/se_ctrl.h b/drivers/firmware/imx/se_ctrl.h
index 7d4f439a6158..7d7469348f1d 100644
--- a/drivers/firmware/imx/se_ctrl.h
+++ b/drivers/firmware/imx/se_ctrl.h
@@ -13,15 +13,62 @@
#define MAX_FW_LOAD_RETRIES 50

#define RES_STATUS(x) FIELD_GET(0x000000ff, x)
+#define MAX_DATA_SIZE_PER_USER (65 * 1024)
+#define MAX_NVM_MSG_LEN (256)
#define MESSAGING_VERSION_6 0x6
#define MESSAGING_VERSION_7 0x7

+#define SE_MU_IO_FLAGS_USE_SEC_MEM (0x02u)
+#define SE_MU_IO_FLAGS_USE_SHORT_ADDR (0x04u)
+
struct se_imem_buf {
u8 *buf;
phys_addr_t phyaddr;
u32 size;
};

+struct se_buf_desc {
+ u8 *shared_buf_ptr;
+ u8 *usr_buf_ptr;
+ u32 size;
+ struct list_head link;
+};
+
+/* Status of a char device */
+enum se_if_dev_ctx_status_t {
+ SE_IF_CTX_FREE,
+ SE_IF_CTX_OPENED
+};
+
+struct se_shared_mem {
+ dma_addr_t dma_addr;
+ u32 size;
+ u32 pos;
+ u8 *ptr;
+};
+
+/* Private struct for each char device instance. */
+struct se_if_device_ctx {
+ struct device *dev;
+ struct se_if_priv *priv;
+ struct miscdevice miscdev;
+
+ enum se_if_dev_ctx_status_t status;
+ wait_queue_head_t wq;
+ struct semaphore fops_lock;
+
+ u32 pending_hdr;
+ struct list_head pending_in;
+ struct list_head pending_out;
+
+ struct se_shared_mem secure_mem;
+ struct se_shared_mem non_secure_mem;
+
+ struct se_api_msg *temp_resp;
+ u32 temp_resp_size;
+ struct notifier_block se_notify;
+};
+
/* Header of the messages exchange with the EdgeLock Enclave */
struct se_msg_hdr {
u8 ver;
@@ -96,4 +143,6 @@ void free_phybuf_mem_pool(struct device *dev,
u8 *mem_pool_name,
u32 *buf,
u32 size);
+int se_dev_ctx_cpy_out_data(struct se_if_device_ctx *dev_ctx);
+void se_dev_ctx_shared_mem_cleanup(struct se_if_device_ctx *dev_ctx);
#endif
diff --git a/include/uapi/linux/se_ioctl.h b/include/uapi/linux/se_ioctl.h
new file mode 100644
index 000000000000..c2d0a92ef626
--- /dev/null
+++ b/include/uapi/linux/se_ioctl.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause*/
+/*
+ * Copyright 2024 NXP
+ */
+
+#ifndef SE_IOCTL_H
+#define SE_IOCTL_H
+
+/* IOCTL definitions. */
+
+struct se_ioctl_setup_iobuf {
+ u8 *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 {
+ u32 *tx_buf;
+ int tx_buf_sz;
+ u32 *rx_buf;
+ int 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

--
2.34.1