[PATCH v6 5/8] bus: mhi: core: Handle firmware load using state worker

Bhaumik Bhatt
2020-05-05T22:47:35Z

Upon power up, driver queues firmware worker thread if the execution
environment is PBL. Firmware worker is blocked with a timeout until
state worker gets a chance to run and unblock firmware worker. An
endpoint power up failure can be seen if state worker gets a chance to
run after firmware worker has timed out. Remove this dependency and
handle firmware load directly using state worker thread.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
---
drivers/bus/mhi/core/boot.c | 18 +++---------------
drivers/bus/mhi/core/init.c | 1 -
drivers/bus/mhi/core/internal.h | 1 +
drivers/bus/mhi/core/pm.c | 6 +-----
include/linux/mhi.h | 2 --
5 files changed, 5 insertions(+), 23 deletions(-)

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index ebad5eb..17c636b 100644
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -377,30 +377,18 @@ static void mhi_firmware_copy(struct mhi_controller *mhi_cntrl,
}
}

-void mhi_fw_load_worker(struct work_struct *work)
+void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
{
- struct mhi_controller *mhi_cntrl;
const struct firmware *firmware = NULL;
struct image_info *image_info;
- struct device *dev;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
const char *fw_name;
void *buf;
dma_addr_t dma_addr;
size_t size;
int ret;

- mhi_cntrl = container_of(work, struct mhi_controller, fw_worker);
- dev = &mhi_cntrl->mhi_dev->dev;
-
- dev_dbg(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)) {
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
dev_err(dev, "Device MHI is not in valid state\n");
return;
}
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 1a93d24..6882206 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -835,7 +835,6 @@ 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 40c47f9..0965ca3 100644
--- a/drivers/bus/mhi/core/internal.h
+++ b/drivers/bus/mhi/core/internal.h
@@ -627,6 +627,7 @@ void mhi_ring_chan_db(struct mhi_controller *mhi_cntrl,
void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl);
void mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
struct image_info *img_info);
+void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl);
int mhi_prepare_channel(struct mhi_controller *mhi_cntrl,
struct mhi_chan *mhi_chan);
int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index e7c8318..3cc238a 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -528,7 +528,6 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
dev_dbg(dev, "Waiting for all pending threads to complete\n");
wake_up_all(&mhi_cntrl->state_event);
flush_work(&mhi_cntrl->st_worker);
- flush_work(&mhi_cntrl->fw_worker);

dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
device_for_each_child(mhi_cntrl->cntrl_dev, NULL, mhi_destroy_device);
@@ -643,7 +642,7 @@ void mhi_pm_st_worker(struct work_struct *work)
mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
write_unlock_irq(&mhi_cntrl->pm_lock);
if (MHI_IN_PBL(mhi_cntrl->ee))
- wake_up_all(&mhi_cntrl->state_event);
+ mhi_fw_load_handler(mhi_cntrl);
break;
case DEV_ST_TRANSITION_SBL:
write_lock_irq(&mhi_cntrl->pm_lock);
@@ -976,9 +975,6 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
next_state = MHI_IN_PBL(current_ee) ?
DEV_ST_TRANSITION_PBL : DEV_ST_TRANSITION_READY;

- if (next_state == DEV_ST_TRANSITION_PBL)
- schedule_work(&mhi_cntrl->fw_worker);
-
mhi_queue_state_transition(mhi_cntrl, next_state);

mutex_unlock(&mhi_cntrl->pm_mutex);
diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index e909b8f..2b20b9c 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -331,7 +331,6 @@ struct mhi_controller_config {
* @wlock: Lock for protecting device wakeup
* @mhi_link_info: Device bandwidth info
* @st_worker: State transition worker
- * @fw_worker: Firmware download worker
* @syserr_worker: System error worker
* @state_event: State change event
* @status_cb: CB function to notify power states of the device (required)
@@ -412,7 +411,6 @@ struct mhi_controller {
spinlock_t wlock;
struct mhi_link_info mhi_link_info;
struct work_struct st_worker;
- struct work_struct fw_worker;
struct work_struct syserr_worker;
wait_queue_head_t state_event;