[PATCH] Revert "drm/amdgpu: enable mcbp by default on gfx9"

[Alex Deucher]

On Wed, Jul 12, 2023 at 2:47 PM Alex Deucher <alexander.deucher at amd.com> wrote:
>
> This reverts commit 50a7c8765ca69543ffdbf855de0fd69aea769ccf.
>
> This breaks some SQA tests on gfx9 dGPUs.  Chistian
> also reported problems.

Apparently this is a bug in mesa which this change uncovered:
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24082/diffs

Alex

>
> Cc: candice.li at amd.com
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 5 -----
>  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    | 6 +++---
>  2 files changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index bbe4ea93db611..3673015a7f93a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -3699,11 +3699,6 @@ static void amdgpu_device_set_mcbp(struct amdgpu_device *adev)
>         if (amdgpu_mcbp == 1)
>                 adev->gfx.mcbp = true;
>
> -       if ((adev->ip_versions[GC_HWIP][0] >= IP_VERSION(9, 0, 0)) &&
> -           (adev->ip_versions[GC_HWIP][0] < IP_VERSION(10, 0, 0)) &&
> -           adev->gfx.num_gfx_rings)
> -               adev->gfx.mcbp = true;
> -
>         if (amdgpu_sriov_vf(adev))
>                 adev->gfx.mcbp = true;
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 33e370d998a87..f829a80e52924 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -180,7 +180,7 @@ uint amdgpu_dc_feature_mask = 2;
>  uint amdgpu_dc_debug_mask;
>  uint amdgpu_dc_visual_confirm;
>  int amdgpu_async_gfx_ring = 1;
> -int amdgpu_mcbp = -1;
> +int amdgpu_mcbp;
>  int amdgpu_discovery = -1;
>  int amdgpu_mes;
>  int amdgpu_mes_kiq;
> @@ -635,10 +635,10 @@ module_param_named(async_gfx_ring, amdgpu_async_gfx_ring, int, 0444);
>
>  /**
>   * DOC: mcbp (int)
> - * It is used to enable mid command buffer preemption. (0 = disabled, 1 = enabled, -1 auto (default))
> + * It is used to enable mid command buffer preemption. (0 = disabled (default), 1 = enabled)
>   */
>  MODULE_PARM_DESC(mcbp,
> -       "Enable Mid-command buffer preemption (0 = disabled, 1 = enabled), -1 = auto (default)");
> +       "Enable Mid-command buffer preemption (0 = disabled (default), 1 = enabled)");
>  module_param_named(mcbp, amdgpu_mcbp, int, 0444);
>
>  /**
> --
> 2.41.0
>