[PATCH 1/1] Revert "drm/amd/display: fix bandwidth validation failure on DCN 2.1"

[Melissa Wen]

On 01/06, LIPSKI, IVAN wrote:
> [AMD Official Use Only - General]
> 
> @Siqueira, Rodrigo<mailto:Rodrigo.Siqueira at amd.com>
> ________________________________
> From: LIPSKI, IVAN <IVAN.LIPSKI at amd.com>
> Sent: January 5, 2024 7:40 PM
> To: amd-gfx at lists.freedesktop.org <amd-gfx at lists.freedesktop.org>
> Cc: rodrigo.siquiera at amd.com <rodrigo.siquiera at amd.com>; Choi, Nicholas <Nicholas.Choi at amd.com>; Deucher, Alexander <Alexander.Deucher at amd.com>; Koenig, Christian <Christian.Koenig at amd.com>; Wentland, Harry <Harry.Wentland at amd.com>; LIPSKI, IVAN <IVAN.LIPSKI at amd.com>; Melissa Wen <mwen at igalia.com>; Mahfooz, Hamza <Hamza.Mahfooz at amd.com>
> Subject: [PATCH 1/1] Revert "drm/amd/display: fix bandwidth validation failure on DCN 2.1"
> 
> From: Ivan Lipski <ivlipski at amd.com>
> 
> This commit causes dmesg-warn on several IGT tests on DCN 3.1.6:
> *ERROR* link_enc_cfg_validate: Invalid link encoder assignments - 0x1c
> 
> Affected IGT tests include:
> amdgpu/[amd_assr|amd_plane|amd_hotplug]
> kms_atomic
> kms_color
> kms_flip
> kms_properties
> kms_universal_plane
> 
> and some other tests
> 
> This reverts commit b7ebd39e2922f642c7ee63ade4a4a5a1ef675d84.

I'm not opposed to reverting this in the short term, but I don't see the
connection between doing a full validation and link encoder assignment
errors. It seems more like the change unveiled an underlying issue
rather than causing the error. I don't see those errors on DCN 2.1 and
3.0.1.

Unfortunately, I don't have a DCN 3.1.6 for debugging :( It'd deserve
further investigation.

Melissa

> 
> Cc: Melissa Wen <mwen at igalia.com>
> Cc: Hamza Mahfooz <hamza.mahfooz at amd.com>
> 
> Signed-off-by: Ivan Lipski <ivlipski at amd.com>
> 
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index d77fc79f3542..111c6f51f0ae 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -10752,7 +10752,7 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>                          DRM_DEBUG_DRIVER("drm_dp_mst_atomic_check() failed\n");
>                          goto fail;
>                  }
> -               status = dc_validate_global_state(dc, dm_state->context, false);
> +               status = dc_validate_global_state(dc, dm_state->context, true);
>                  if (status != DC_OK) {
>                          DRM_DEBUG_DRIVER("DC global validation failure: %s (%d)",
>                                         dc_status_to_str(status), status);
> --
> 2.34.1
>