There are some hardware logic under CX domain. For a successful
recovery, we should ensure cx headswitch collapses to ensure all the
stale states are cleard out. This is especially true to for a6xx family
where we can GMU co-processor.
Currently, cx doesn't collapse due to a devlink between gpu and its
smmu. So the *struct gpu device* needs to be runtime suspended to ensure
that the iommu driver removes its vote on cx gdsc.
Signed-off-by: Akhil P Oommen <[email protected]>
---
Changes in v3:
- Simplied the pm refcount drop since we have just a single refcount now
for all active submits
drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 24 +++++++++++++++++++++---
drivers/gpu/drm/msm/msm_gpu.c | 4 +---
2 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 42ed9a3..1b049c5 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -1193,7 +1193,7 @@ static void a6xx_recover(struct msm_gpu *gpu)
{
struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
- int i;
+ int i, active_submits;
adreno_dump_info(gpu);
@@ -1210,8 +1210,26 @@ static void a6xx_recover(struct msm_gpu *gpu)
*/
gmu_write(&a6xx_gpu->gmu, REG_A6XX_GMU_GMU_PWR_COL_KEEPALIVE, 0);
- gpu->funcs->pm_suspend(gpu);
- gpu->funcs->pm_resume(gpu);
+ pm_runtime_dont_use_autosuspend(&gpu->pdev->dev);
+
+ /* active_submit won't change until we make a submission */
+ mutex_lock(&gpu->active_lock);
+ active_submits = gpu->active_submits;
+ mutex_unlock(&gpu->active_lock);
+
+ /* Drop the rpm refcount from active submits */
+ if (active_submits)
+ pm_runtime_put(&gpu->pdev->dev);
+
+ /* And the final one from recover worker */
+ pm_runtime_put_sync(&gpu->pdev->dev);
+
+ pm_runtime_use_autosuspend(&gpu->pdev->dev);
+
+ if (active_submits)
+ pm_runtime_get(&gpu->pdev->dev);
+
+ pm_runtime_get_sync(&gpu->pdev->dev);
msm_gpu_hw_init(gpu);
}
diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 1945efb..07e55a6 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -426,9 +426,7 @@ static void recover_worker(struct kthread_work *work)
/* retire completed submits, plus the one that hung: */
retire_submits(gpu);
- pm_runtime_get_sync(&gpu->pdev->dev);
gpu->funcs->recover(gpu);
- pm_runtime_put_sync(&gpu->pdev->dev);
/*
* Replay all remaining submits starting with highest priority
@@ -445,7 +443,7 @@ static void recover_worker(struct kthread_work *work)
}
}
- pm_runtime_put_sync(&gpu->pdev->dev);
+ pm_runtime_put(&gpu->pdev->dev);
mutex_unlock(&gpu->lock);
--
2.7.4
On Sat, Jul 30, 2022 at 2:41 AM Akhil P Oommen <[email protected]> wrote:
>
> There are some hardware logic under CX domain. For a successful
> recovery, we should ensure cx headswitch collapses to ensure all the
> stale states are cleard out. This is especially true to for a6xx family
> where we can GMU co-processor.
>
> Currently, cx doesn't collapse due to a devlink between gpu and its
> smmu. So the *struct gpu device* needs to be runtime suspended to ensure
> that the iommu driver removes its vote on cx gdsc.
>
> Signed-off-by: Akhil P Oommen <[email protected]>
> ---
>
> Changes in v3:
> - Simplied the pm refcount drop since we have just a single refcount now
> for all active submits
>
> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 24 +++++++++++++++++++++---
> drivers/gpu/drm/msm/msm_gpu.c | 4 +---
> 2 files changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> index 42ed9a3..1b049c5 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> @@ -1193,7 +1193,7 @@ static void a6xx_recover(struct msm_gpu *gpu)
> {
> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
> struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
> - int i;
> + int i, active_submits;
>
> adreno_dump_info(gpu);
>
> @@ -1210,8 +1210,26 @@ static void a6xx_recover(struct msm_gpu *gpu)
> */
> gmu_write(&a6xx_gpu->gmu, REG_A6XX_GMU_GMU_PWR_COL_KEEPALIVE, 0);
>
> - gpu->funcs->pm_suspend(gpu);
> - gpu->funcs->pm_resume(gpu);
> + pm_runtime_dont_use_autosuspend(&gpu->pdev->dev);
> +
> + /* active_submit won't change until we make a submission */
> + mutex_lock(&gpu->active_lock);
> + active_submits = gpu->active_submits;
> + mutex_unlock(&gpu->active_lock);
> +
> + /* Drop the rpm refcount from active submits */
> + if (active_submits)
> + pm_runtime_put(&gpu->pdev->dev);
Couldn't this race with an incoming submit triggering active_submits
to transition 0 -> 1? Moving the mutex_unlock() would solve this.
Actually, maybe just move the mutex_unlock() to the end of the entire
sequence. You could also clear gpu->active_submits and restore it
before unlocking, so you can drop the removal of the WARN_ON_ONCE
(patch 6/8) which should otherwise be squashed into this patch to keep
things bisectable
> +
> + /* And the final one from recover worker */
> + pm_runtime_put_sync(&gpu->pdev->dev);
> +
> + pm_runtime_use_autosuspend(&gpu->pdev->dev);
> +
> + if (active_submits)
> + pm_runtime_get(&gpu->pdev->dev);
> +
> + pm_runtime_get_sync(&gpu->pdev->dev);
>
> msm_gpu_hw_init(gpu);
> }
> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> index 1945efb..07e55a6 100644
> --- a/drivers/gpu/drm/msm/msm_gpu.c
> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> @@ -426,9 +426,7 @@ static void recover_worker(struct kthread_work *work)
> /* retire completed submits, plus the one that hung: */
> retire_submits(gpu);
>
> - pm_runtime_get_sync(&gpu->pdev->dev);
> gpu->funcs->recover(gpu);
> - pm_runtime_put_sync(&gpu->pdev->dev);
Hmm, could this have some fallout on earlier gens?
I guess I should extend the igt msm_recovery test to run on things
prior to a6xx..
BR,
-R
>
> /*
> * Replay all remaining submits starting with highest priority
> @@ -445,7 +443,7 @@ static void recover_worker(struct kthread_work *work)
> }
> }
>
> - pm_runtime_put_sync(&gpu->pdev->dev);
> + pm_runtime_put(&gpu->pdev->dev);
>
> mutex_unlock(&gpu->lock);
>
> --
> 2.7.4
>
On 7/31/2022 9:52 PM, Rob Clark wrote:
> On Sat, Jul 30, 2022 at 2:41 AM Akhil P Oommen <[email protected]> wrote:
>> There are some hardware logic under CX domain. For a successful
>> recovery, we should ensure cx headswitch collapses to ensure all the
>> stale states are cleard out. This is especially true to for a6xx family
>> where we can GMU co-processor.
>>
>> Currently, cx doesn't collapse due to a devlink between gpu and its
>> smmu. So the *struct gpu device* needs to be runtime suspended to ensure
>> that the iommu driver removes its vote on cx gdsc.
>>
>> Signed-off-by: Akhil P Oommen <[email protected]>
>> ---
>>
>> Changes in v3:
>> - Simplied the pm refcount drop since we have just a single refcount now
>> for all active submits
>>
>> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 24 +++++++++++++++++++++---
>> drivers/gpu/drm/msm/msm_gpu.c | 4 +---
>> 2 files changed, 22 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> index 42ed9a3..1b049c5 100644
>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> @@ -1193,7 +1193,7 @@ static void a6xx_recover(struct msm_gpu *gpu)
>> {
>> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>> struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
>> - int i;
>> + int i, active_submits;
>>
>> adreno_dump_info(gpu);
>>
>> @@ -1210,8 +1210,26 @@ static void a6xx_recover(struct msm_gpu *gpu)
>> */
>> gmu_write(&a6xx_gpu->gmu, REG_A6XX_GMU_GMU_PWR_COL_KEEPALIVE, 0);
>>
>> - gpu->funcs->pm_suspend(gpu);
>> - gpu->funcs->pm_resume(gpu);
>> + pm_runtime_dont_use_autosuspend(&gpu->pdev->dev);
>> +
>> + /* active_submit won't change until we make a submission */
>> + mutex_lock(&gpu->active_lock);
>> + active_submits = gpu->active_submits;
>> + mutex_unlock(&gpu->active_lock);
>> +
>> + /* Drop the rpm refcount from active submits */
>> + if (active_submits)
>> + pm_runtime_put(&gpu->pdev->dev);
> Couldn't this race with an incoming submit triggering active_submits
> to transition 0 -> 1? Moving the mutex_unlock() would solve this.
>
> Actually, maybe just move the mutex_unlock() to the end of the entire
> sequence. You could also clear gpu->active_submits and restore it
> before unlocking, so you can drop the removal of the WARN_ON_ONCE
> (patch 6/8) which should otherwise be squashed into this patch to keep
> things bisectable
Because we are holding gpu->lock, there won't be any new submissions to
gpu. But I agree with your both suggestions.
-Akhil.
>
>> +
>> + /* And the final one from recover worker */
>> + pm_runtime_put_sync(&gpu->pdev->dev);
>> +
>> + pm_runtime_use_autosuspend(&gpu->pdev->dev);
>> +
>> + if (active_submits)
>> + pm_runtime_get(&gpu->pdev->dev);
>> +
>> + pm_runtime_get_sync(&gpu->pdev->dev);
>>
>> msm_gpu_hw_init(gpu);
>> }
>> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
>> index 1945efb..07e55a6 100644
>> --- a/drivers/gpu/drm/msm/msm_gpu.c
>> +++ b/drivers/gpu/drm/msm/msm_gpu.c
>> @@ -426,9 +426,7 @@ static void recover_worker(struct kthread_work *work)
>> /* retire completed submits, plus the one that hung: */
>> retire_submits(gpu);
>>
>> - pm_runtime_get_sync(&gpu->pdev->dev);
>> gpu->funcs->recover(gpu);
>> - pm_runtime_put_sync(&gpu->pdev->dev);
> Hmm, could this have some fallout on earlier gens?
>
> I guess I should extend the igt msm_recovery test to run on things
> prior to a6xx..
>
> BR,
> -R
No, because of patch 3/8 in this series.
-Akhil.
>
>> /*
>> * Replay all remaining submits starting with highest priority
>> @@ -445,7 +443,7 @@ static void recover_worker(struct kthread_work *work)
>> }
>> }
>>
>> - pm_runtime_put_sync(&gpu->pdev->dev);
>> + pm_runtime_put(&gpu->pdev->dev);
>>
>> mutex_unlock(&gpu->lock);
>>
>> --
>> 2.7.4
>>