[PATCH 08/16] bus: mhi: core: Add support for downloading firmware over BHIe

Manivannan Sadhasivam
2020-01-23T11:19:16Z

MHI supports downloading the device firmware over BHI/BHIe (Boot Host
Interface) protocol. Hence, this commit adds necessary helpers, which
will be called during device power up stage.

This is based on the patch submitted by Sujeev Dias:
https://lkml.org/lkml/2018/7/9/989

Signed-off-by: Sujeev Dias <sdias@codeaurora.org>
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>
[mani: splitted the data transfer patch and cleaned up for upstream]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
drivers/bus/mhi/core/boot.c | 268 ++++++++++++++++++++++++++++++++
drivers/bus/mhi/core/init.c | 1 +
drivers/bus/mhi/core/internal.h | 1 +
3 files changed, 270 insertions(+)

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index 0996f18c4281..36956fb6eff2 100644
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -20,6 +20,121 @@
#include <linux/wait.h>
#include "internal.h"

+/* Download AMSS image to device */
+static int mhi_fw_load_amss(struct mhi_controller *mhi_cntrl,
+ const struct mhi_buf *mhi_buf)
+{
+ void __iomem *base = mhi_cntrl->bhie;
+ rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
+ u32 tx_status, sequence_id;
+
+ read_lock_bh(pm_lock);
+ if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+ read_unlock_bh(pm_lock);
+ return -EIO;
+ }
+
+ mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_HIGH_OFFS,
+ upper_32_bits(mhi_buf->dma_addr));
+
+ mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_LOW_OFFS,
+ lower_32_bits(mhi_buf->dma_addr));
+
+ mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len);
+
+ sequence_id = prandom_u32() & BHIE_TXVECSTATUS_SEQNUM_BMSK;
+ mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS,
+ BHIE_TXVECDB_SEQNUM_BMSK, BHIE_TXVECDB_SEQNUM_SHFT,
+ sequence_id);
+ read_unlock_bh(pm_lock);
+
+ /* Wait for the image download to complete */
+ wait_event_timeout(mhi_cntrl->state_event,
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
+ mhi_read_reg_field(mhi_cntrl, base,
+ BHIE_TXVECSTATUS_OFFS,
+ BHIE_TXVECSTATUS_STATUS_BMSK,
+ BHIE_TXVECSTATUS_STATUS_SHFT,
+ &tx_status) || tx_status,
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+ return -EIO;
+
+ return (tx_status == BHIE_TXVECSTATUS_STATUS_XFER_COMPL) ? 0 : -EIO;
+}
+
+/* Download SBL image to device */
+static int mhi_fw_load_sbl(struct mhi_controller *mhi_cntrl,
+ dma_addr_t dma_addr,
+ size_t size)
+{
+ u32 tx_status, val, session_id;
+ int i, ret;
+ void __iomem *base = mhi_cntrl->bhi;
+ rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
+ struct {
+ char *name;
+ u32 offset;
+ } error_reg[] = {
+ { "ERROR_CODE", BHI_ERRCODE },
+ { "ERROR_DBG1", BHI_ERRDBG1 },
+ { "ERROR_DBG2", BHI_ERRDBG2 },
+ { "ERROR_DBG3", BHI_ERRDBG3 },
+ { NULL },
+ };
+
+ read_lock_bh(pm_lock);
+ if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+ read_unlock_bh(pm_lock);
+ goto invalid_pm_state;
+ }
+
+ /* Start SBL download via BHI protocol */
+ mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
+ mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
+ upper_32_bits(dma_addr));
+ mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
+ lower_32_bits(dma_addr));
+ mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
+ session_id = prandom_u32() & BHI_TXDB_SEQNUM_BMSK;
+ mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
+ read_unlock_bh(pm_lock);
+
+ /* Wait for the image download to complete */
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
+ mhi_read_reg_field(mhi_cntrl, base, BHI_STATUS,
+ BHI_STATUS_MASK, BHI_STATUS_SHIFT,
+ &tx_status) || tx_status,
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+ goto invalid_pm_state;
+
+ if (tx_status == BHI_STATUS_ERROR) {
+ dev_err(mhi_cntrl->dev, "Image transfer failed\n");
+ read_lock_bh(pm_lock);
+ if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+ for (i = 0; error_reg[i].name; i++) {
+ ret = mhi_read_reg(mhi_cntrl, base,
+ error_reg[i].offset, &val);
+ if (ret)
+ break;
+ dev_err(mhi_cntrl->dev, "Reg: %s value: 0x%x\n",
+ error_reg[i].name, val);
+ }
+ }
+ read_unlock_bh(pm_lock);
+ goto invalid_pm_state;
+ }
+
+ return (!ret) ? -ETIMEDOUT : 0;
+
+invalid_pm_state:
+
+ return -EIO;
+}
+
void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl,
struct image_info *image_info)
{
@@ -87,3 +202,156 @@ int mhi_alloc_bhie_table(struct mhi_controller *mhi_cntrl,

return -ENOMEM;
}
+
+static void mhi_firmware_copy(struct mhi_controller *mhi_cntrl,
+ const struct firmware *firmware,
+ struct image_info *img_info)
+{
+ size_t remainder = firmware->size;
+ size_t to_cpy;
+ const u8 *buf = firmware->data;
+ int i = 0;
+ struct mhi_buf *mhi_buf = img_info->mhi_buf;
+ struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
+
+ while (remainder) {
+ to_cpy = min(remainder, mhi_buf->len);
+ memcpy(mhi_buf->buf, buf, to_cpy);
+ bhi_vec->dma_addr = mhi_buf->dma_addr;
+ bhi_vec->size = to_cpy;
+
+ buf += to_cpy;
+ remainder -= to_cpy;
+ i++;
+ bhi_vec++;
+ mhi_buf++;
+ }
+}
+
+void mhi_fw_load_worker(struct work_struct *work)
+{
+ int ret;
+ struct mhi_controller *mhi_cntrl;
+ const char *fw_name;
+ const struct firmware *firmware = NULL;
+ struct image_info *image_info;
+ void *buf;
+ dma_addr_t dma_addr;
+ size_t size;
+
+ mhi_cntrl = container_of(work, struct mhi_controller, fw_worker);
+
+ dev_dbg(mhi_cntrl->dev, "Waiting for device to enter PBL from: %s\n",
+ TO_MHI_EXEC_STR(mhi_cntrl->ee));
+
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ MHI_IN_PBL(mhi_cntrl->ee) ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ dev_err(mhi_cntrl->dev, "Device MHI is not in valid state\n");
+ return;
+ }
+
+ /* If device is in pass through, do reset to ready state transition */
+ if (mhi_cntrl->ee == MHI_EE_PTHRU)
+ goto fw_load_ee_pthru;
+
+ fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
+ mhi_cntrl->edl_image : mhi_cntrl->fw_image;
+
+ if (!fw_name || (mhi_cntrl->fbc_download && (!mhi_cntrl->sbl_size ||
+ !mhi_cntrl->seg_len))) {
+ dev_err(mhi_cntrl->dev,
+ "No firmware image defined or !sbl_size || !seg_len\n");
+ return;
+ }
+
+ ret = request_firmware(&firmware, fw_name, mhi_cntrl->dev);
+ if (ret) {
+ dev_err(mhi_cntrl->dev, "Error loading firmware: %d\n",
+ ret);
+ return;
+ }
+
+ size = (mhi_cntrl->fbc_download) ? mhi_cntrl->sbl_size : firmware->size;
+
+ /* SBL size provided is maximum size, not necessarily the image size */
+ if (size > firmware->size)
+ size = firmware->size;
+
+ buf = mhi_alloc_coherent(mhi_cntrl, size, &dma_addr, GFP_KERNEL);
+ if (!buf) {
+ release_firmware(firmware);
+ return;
+ }
+
+ /* Download SBL image */
+ memcpy(buf, firmware->data, size);
+ ret = mhi_fw_load_sbl(mhi_cntrl, dma_addr, size);
+ mhi_free_coherent(mhi_cntrl, size, buf, dma_addr);
+
+ if (!mhi_cntrl->fbc_download || ret || mhi_cntrl->ee == MHI_EE_EDL)
+ release_firmware(firmware);
+
+ /* Error or in EDL mode, we're done */
+ if (ret || mhi_cntrl->ee == MHI_EE_EDL)
+ return;
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_cntrl->dev_state = MHI_STATE_RESET;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ /*
+ * If we're doing fbc, populate vector tables while
+ * device transitioning into MHI READY state
+ */
+ if (mhi_cntrl->fbc_download) {
+ ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image,
+ firmware->size);
+ if (ret)
+ goto error_alloc_fw_table;
+
+ /* Load the firmware into BHIE vec table */
+ mhi_firmware_copy(mhi_cntrl, firmware, mhi_cntrl->fbc_image);
+ }
+
+fw_load_ee_pthru:
+ /* Transitioning into MHI RESET->READY state */
+ ret = mhi_ready_state_transition(mhi_cntrl);
+
+ if (!mhi_cntrl->fbc_download)
+ return;
+
+ if (ret)
+ goto error_read;
+
+ /* Wait for the SBL event */
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->ee == MHI_EE_SBL ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ dev_err(mhi_cntrl->dev, "MHI did not enter SBL\n");
+ goto error_read;
+ }
+
+ /* Start full firmware image download */
+ image_info = mhi_cntrl->fbc_image;
+ ret = mhi_fw_load_amss(mhi_cntrl,
+ /* Vector table is the last entry */
+ &image_info->mhi_buf[image_info->entries - 1]);
+
+ release_firmware(firmware);
+
+ return;
+
+error_read:
+ mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
+ mhi_cntrl->fbc_image = NULL;
+
+error_alloc_fw_table:
+ release_firmware(firmware);
+}
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 7fff92e9661b..2f06bf958f58 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -753,6 +753,7 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
spin_lock_init(&mhi_cntrl->wlock);
INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
INIT_WORK(&mhi_cntrl->syserr_worker, mhi_pm_sys_err_worker);
+ INIT_WORK(&mhi_cntrl->fw_worker, mhi_fw_load_worker);
init_waitqueue_head(&mhi_cntrl->state_event);

mhi_cmd = mhi_cntrl->mhi_cmd;
diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h
index d920264ded21..eab9c051ca5e 100644
--- a/drivers/bus/mhi/core/internal.h
+++ b/drivers/bus/mhi/core/internal.h
@@ -590,6 +590,7 @@ int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
enum dev_st_transition state);
void mhi_pm_st_worker(struct work_struct *work);
void mhi_pm_sys_err_worker(struct work_struct *work);
+void mhi_fw_load_worker(struct work_struct *work);
int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl);
void mhi_ctrl_ev_task(unsigned long data);
int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl);
--
2.17.1