[v1,6/7] bus: mhi: core: Wait for MHI READY state in most scenarios
diff mbox series

Message ID 1617067704-28850-7-git-send-email-bbhatt@codeaurora.org
State Accepted
Commit e72919cebd19618b7341e69034b4d9f7120ff4de
Headers show
Series
  • MHI Emergency download and flash programmer support
Related show

Commit Message

Bhaumik Bhatt March 30, 2021, 1:28 a.m. UTC
When moving from SYS_ERROR transition to a different execution
environment, MHI host relies on the BHI register read to spawn
the next image download or wait for READY -> M0 states. The
device can at times move the execution environment to mission
mode when a pass through is expected, which can result in a
stall. Initiate a wait for MHI READY and write M0 such that the
device can proceed with state change event updates for any new
execution environment being entered. This allows us to remove
conditionals in handling firmware load for PBL modes and keeps
the execution environment out of the picture as it can change at
any time.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 drivers/bus/mhi/core/boot.c | 4 ++--
 drivers/bus/mhi/core/pm.c   | 3 +--
 2 files changed, 3 insertions(+), 4 deletions(-)

Comments

Loic Poulain March 30, 2021, 8:03 a.m. UTC | #1
On Tue, 30 Mar 2021 at 03:28, Bhaumik Bhatt <bbhatt@codeaurora.org> wrote:
>
> When moving from SYS_ERROR transition to a different execution
> environment, MHI host relies on the BHI register read to spawn
> the next image download or wait for READY -> M0 states. The
> device can at times move the execution environment to mission
> mode when a pass through is expected, which can result in a
> stall. Initiate a wait for MHI READY and write M0 such that the
> device can proceed with state change event updates for any new
> execution environment being entered. This allows us to remove
> conditionals in handling firmware load for PBL modes and keeps
> the execution environment out of the picture as it can change at
> any time.
>
> Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>

Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Manivannan Sadhasivam March 31, 2021, 11:13 a.m. UTC | #2
On Mon, Mar 29, 2021 at 06:28:23PM -0700, Bhaumik Bhatt wrote:
> When moving from SYS_ERROR transition to a different execution
> environment, MHI host relies on the BHI register read to spawn
> the next image download or wait for READY -> M0 states. The
> device can at times move the execution environment to mission
> mode when a pass through is expected, which can result in a
> stall. Initiate a wait for MHI READY and write M0 such that the
> device can proceed with state change event updates for any new
> execution environment being entered. This allows us to remove
> conditionals in handling firmware load for PBL modes and keeps
> the execution environment out of the picture as it can change at
> any time.
> 
> Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thanks,
Mani

> ---
>  drivers/bus/mhi/core/boot.c | 4 ++--
>  drivers/bus/mhi/core/pm.c   | 3 +--
>  2 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
> index 0f0ae88..8100cf5 100644
> --- a/drivers/bus/mhi/core/boot.c
> +++ b/drivers/bus/mhi/core/boot.c
> @@ -416,8 +416,8 @@ void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
>  		}
>  	}
>  
> -	/* If device is in pass through, do reset to ready state transition */
> -	if (mhi_cntrl->ee == MHI_EE_PTHRU)
> +	/* wait for ready on pass through or any other execution environment */
> +	if (mhi_cntrl->ee != MHI_EE_EDL && mhi_cntrl->ee != MHI_EE_PBL)
>  		goto fw_load_ready_state;
>  
>  	fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
> diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
> index 7ac9dfe..b6920a5 100644
> --- a/drivers/bus/mhi/core/pm.c
> +++ b/drivers/bus/mhi/core/pm.c
> @@ -763,8 +763,7 @@ void mhi_pm_st_worker(struct work_struct *work)
>  			if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
>  				mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
>  			write_unlock_irq(&mhi_cntrl->pm_lock);
> -			if (MHI_IN_PBL(mhi_cntrl->ee))
> -				mhi_fw_load_handler(mhi_cntrl);
> +			mhi_fw_load_handler(mhi_cntrl);
>  			break;
>  		case DEV_ST_TRANSITION_SBL:
>  			write_lock_irq(&mhi_cntrl->pm_lock);
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>

Patch
diff mbox series

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index 0f0ae88..8100cf5 100644
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -416,8 +416,8 @@  void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
 		}
 	}
 
-	/* If device is in pass through, do reset to ready state transition */
-	if (mhi_cntrl->ee == MHI_EE_PTHRU)
+	/* wait for ready on pass through or any other execution environment */
+	if (mhi_cntrl->ee != MHI_EE_EDL && mhi_cntrl->ee != MHI_EE_PBL)
 		goto fw_load_ready_state;
 
 	fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 7ac9dfe..b6920a5 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -763,8 +763,7 @@  void mhi_pm_st_worker(struct work_struct *work)
 			if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
 				mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
 			write_unlock_irq(&mhi_cntrl->pm_lock);
-			if (MHI_IN_PBL(mhi_cntrl->ee))
-				mhi_fw_load_handler(mhi_cntrl);
+			mhi_fw_load_handler(mhi_cntrl);
 			break;
 		case DEV_ST_TRANSITION_SBL:
 			write_lock_irq(&mhi_cntrl->pm_lock);