Re: [PATCH] drm/amdgpu: Skip access GRBM_CNTL under SRIOV on gfx_v11

[Alex Deucher]

On Tue, Oct 25, 2022 at 5:06 AM Yifan Zha  wrote:
>
> [Why]
> GRBM_CNTL is a PF_only register on gfx_v11.
> RLCG interface will return "out of range" under SRIOV VF.
>
> [How]
> Skip access GRBM_CNTL under gfx_v11 SRIOV VF.
>
> Signed-off-by: Yifan Zha 

Acked-by: Alex Deucher 

> ---
>  drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c 
> b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
> index e3842dc100d6..1330768df0b1 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
> @@ -1626,7 +1626,8 @@ static void gfx_v11_0_constants_init(struct 
> amdgpu_device *adev)
> u32 tmp;
> int i;
>
> -   WREG32_FIELD15_PREREG(GC, 0, GRBM_CNTL, READ_TIMEOUT, 0xff);
> +   if (!amdgpu_sriov_vf(adev))
> +   WREG32_FIELD15_PREREG(GC, 0, GRBM_CNTL, READ_TIMEOUT, 0xff);
>
> gfx_v11_0_setup_rb(adev);
> gfx_v11_0_get_cu_info(adev, &adev->gfx.cu_info);
> --
> 2.25.1
>

[PATCH] drm/amdgpu: Skip access GRBM_CNTL under SRIOV on gfx_v11

[Yifan Zha]

[Why]
GRBM_CNTL is a PF_only register on gfx_v11.
RLCG interface will return "out of range" under SRIOV VF.

[How]
Skip access GRBM_CNTL under gfx_v11 SRIOV VF.

Signed-off-by: Yifan Zha 
---
 drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c 
b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
index e3842dc100d6..1330768df0b1 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c
@@ -1626,7 +1626,8 @@ static void gfx_v11_0_constants_init(struct amdgpu_device 
*adev)
u32 tmp;
int i;
 
-   WREG32_FIELD15_PREREG(GC, 0, GRBM_CNTL, READ_TIMEOUT, 0xff);
+   if (!amdgpu_sriov_vf(adev))
+   WREG32_FIELD15_PREREG(GC, 0, GRBM_CNTL, READ_TIMEOUT, 0xff);
 
gfx_v11_0_setup_rb(adev);
gfx_v11_0_get_cu_info(adev, &adev->gfx.cu_info);
-- 
2.25.1