[PATCH] drm/amd/display: disable SG displays on cyan skillfish

[Harry Wentland]

On 2024-10-04 10:30, Alex Deucher wrote:
> These parts were mainly for compute workloads, but they have
> a display that was available for the console.  These chips
> should support SG display, but I don't know that the support
> was ever validated on Linux so disable it by default. It can
> still be enabled by setting sg_display=1 for those that
> want to play with it.  These systems also generally had large
> carve outs so SG display was less of a factor.
> 
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3356
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>

Reviewed-by: Harry Wentland <harry.wentland at amd.com>

Harry

> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 +++++-
>  1 file changed, 5 insertions(+), 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 7616d7a509b9..84fdfb4c8bd0 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1886,7 +1886,11 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
>  		else
>  			init_data.flags.gpu_vm_support = (amdgpu_sg_display != 0);
>  	} else {
> -		init_data.flags.gpu_vm_support = (amdgpu_sg_display != 0) && (adev->flags & AMD_IS_APU);
> +		if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(2, 0, 3))
> +			init_data.flags.gpu_vm_support = (amdgpu_sg_display == 1);
> +		else
> +			init_data.flags.gpu_vm_support =
> +				(amdgpu_sg_display != 0) && (adev->flags & AMD_IS_APU);
>  	}
>  
>  	adev->mode_info.gpu_vm_support = init_data.flags.gpu_vm_support;