[PATCH v2] drm/amdgpu: fix that issue that the number of the crtc of the 3250c is not correct

[Paul Menzel]

Dear Tsung-Hua,


Thank you for your patch.

Am 30.03.22 um 04:46 schrieb Ryan Lin:

The commit message summary is quite long and confusing. Maybe:

Use 3 CRTC for 3250c to get internal display working

> [Why]
> External displays take priority over internal display when there are fewer
> display controllers than displays.

This causes the internal display to not work on the Chromebook google/zork.

> [How]
> The root cause is because of that number of the crtc is not correct.

The root cause is the incorrect number of four configured CRTCs.

> The number of the crtc on the 3250c is 3, but on the 3500c is 4.
> On the source code, we can see that number of the crtc has been fixed at 4.
> Needs to set the num_crtc to 3 for 3250c platform.

Please do not wrap lines after each sentence, and use a text width of 75 
characters.

> v2:
>     - remove unnecessary comments and Id
> 
> Signed-off-by: Ryan Lin <tsung-hua.lin at amd.com>
> 
> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 12 +++++++++---
>   1 file changed, 9 insertions(+), 3 deletions(-)
> 
> 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 40c91b448f7da..455a2c45e8cda 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -2738,9 +2738,15 @@ static int dm_early_init(void *handle)
>   		break;
>   #if defined(CONFIG_DRM_AMD_DC_DCN1_0)
>   	case CHIP_RAVEN:
> -		adev->mode_info.num_crtc = 4;
> -		adev->mode_info.num_hpd = 4;
> -		adev->mode_info.num_dig = 4;
> +		if (adev->rev_id >= 8) {

Is there some define for that number? Maybe add a comment, that it’s for 
3250c?


Kind regards,

Paul


> +			adev->mode_info.num_crtc = 3;
> +			adev->mode_info.num_hpd = 3;
> +			adev->mode_info.num_dig = 3;
> +		} else {
> +			adev->mode_info.num_crtc = 4;
> +			adev->mode_info.num_hpd = 4;
> +			adev->mode_info.num_dig = 4;
> +		}
>   		break;
>   #endif
>   #if defined(CONFIG_DRM_AMD_DC_DCN2_0)