2021-03-25 03:40:22

by Rob Clark

Subject: [PATCH 1/2] drm/msm: Fix a5xx/a6xx timestamps

From: Rob Clark <[email protected]>

They were reading a counter that was configured to ALWAYS_COUNT (ie.
cycles that the GPU is doing something) rather than ALWAYS_ON. This
isn't the thing that userspace is looking for.

Signed-off-by: Rob Clark <[email protected]>
---
drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 4 ++--
drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
index a5af223eaf50..bb82fcd9df81 100644
--- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
@@ -1241,8 +1241,8 @@ static int a5xx_pm_suspend(struct msm_gpu *gpu)

static int a5xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
{
- *value = gpu_read64(gpu, REG_A5XX_RBBM_PERFCTR_CP_0_LO,
- REG_A5XX_RBBM_PERFCTR_CP_0_HI);
+ *value = gpu_read64(gpu, REG_A5XX_RBBM_ALWAYSON_COUNTER_LO,
+ REG_A5XX_RBBM_ALWAYSON_COUNTER_HI);

return 0;
}
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 130661898546..59718c304488 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -1173,8 +1173,8 @@ static int a6xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
/* Force the GPU power on so we can read this register */
a6xx_gmu_set_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);

- *value = gpu_read64(gpu, REG_A6XX_RBBM_PERFCTR_CP_0_LO,
- REG_A6XX_RBBM_PERFCTR_CP_0_HI);
+ *value = gpu_read64(gpu, REG_A6XX_CP_ALWAYS_ON_COUNTER_LO,
+ REG_A6XX_CP_ALWAYS_ON_COUNTER_HI);

a6xx_gmu_clear_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);
return 0;
--
2.29.2

2021-04-02 14:50:47

by Jordan Crouse

Subject: Re: [Freedreno] [PATCH 1/2] drm/msm: Fix a5xx/a6xx timestamps

On Wed, Mar 24, 2021 at 06:23:52PM -0700, Rob Clark wrote:
> From: Rob Clark <[email protected]>
>
> They were reading a counter that was configured to ALWAYS_COUNT (ie.
> cycles that the GPU is doing something) rather than ALWAYS_ON. This
> isn't the thing that userspace is looking for.

Acked-by: Jordan Crouse <[email protected]>

> Signed-off-by: Rob Clark <[email protected]>
> ---
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 4 ++--
> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 4 ++--
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> index a5af223eaf50..bb82fcd9df81 100644
> --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> @@ -1241,8 +1241,8 @@ static int a5xx_pm_suspend(struct msm_gpu *gpu)
>
> static int a5xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
> {
> - *value = gpu_read64(gpu, REG_A5XX_RBBM_PERFCTR_CP_0_LO,
> - REG_A5XX_RBBM_PERFCTR_CP_0_HI);
> + *value = gpu_read64(gpu, REG_A5XX_RBBM_ALWAYSON_COUNTER_LO,
> + REG_A5XX_RBBM_ALWAYSON_COUNTER_HI);
>
> return 0;
> }
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> index 130661898546..59718c304488 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> @@ -1173,8 +1173,8 @@ static int a6xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
> /* Force the GPU power on so we can read this register */
> a6xx_gmu_set_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);
>
> - *value = gpu_read64(gpu, REG_A6XX_RBBM_PERFCTR_CP_0_LO,
> - REG_A6XX_RBBM_PERFCTR_CP_0_HI);
> + *value = gpu_read64(gpu, REG_A6XX_CP_ALWAYS_ON_COUNTER_LO,
> + REG_A6XX_CP_ALWAYS_ON_COUNTER_HI);
>
> a6xx_gmu_clear_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);
> return 0;
> --
> 2.29.2
>
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