In general lgtm.

Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>

Mark Yacoub, do you have any comment?

On 04/05, Qingqing Zhuo wrote:
> This reverts commit 9f81b5d40ca2c689334ad8288a4ddca4722a6e10.
> 
> The original commit was found to cause the following two issues
> on sienna cichlid:
> 1. Refresh rate locked during vrrdemo
> 2. Display sticks on flipped landscape mode after changing
>    orientation, and cannot be changed back to regular landscape
> 
> Signed-off-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_display.c    | 13 -------------
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c  | 18 +++---------------
>  2 files changed, 3 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> index 0f17984fdea4..6304a49b02fd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> @@ -908,19 +908,6 @@ int amdgpu_display_gem_fb_verify_and_init(
>  					 &amdgpu_fb_funcs);
>  	if (ret)
>  		goto err;
> -	/* Verify that the modifier is supported. */
> -	if (!drm_any_plane_has_format(dev, mode_cmd->pixel_format,
> -				      mode_cmd->modifier[0])) {
> -		struct drm_format_name_buf format_name;
> -		drm_dbg_kms(dev,
> -			    "unsupported pixel format %s / modifier 0x%llx\n",
> -			    drm_get_format_name(mode_cmd->pixel_format,
> -						&format_name),
> -			    mode_cmd->modifier[0]);
> -
> -		ret = -EINVAL;
> -		goto err;
> -	}
>  
>  	ret = amdgpu_display_framebuffer_init(dev, rfb, mode_cmd, obj);
>  	if (ret)
> 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 54ef0f3f37b7..ac6ab35f89b2 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -4299,7 +4299,6 @@ static bool dm_plane_format_mod_supported(struct drm_plane *plane,
>  {
>  	struct amdgpu_device *adev = drm_to_adev(plane->dev);
>  	const struct drm_format_info *info = drm_format_info(format);
> -	int i;
>  
>  	enum dm_micro_swizzle microtile = modifier_gfx9_swizzle_mode(modifier) & 3;
>  
> @@ -4307,22 +4306,11 @@ static bool dm_plane_format_mod_supported(struct drm_plane *plane,
>  		return false;
>  
>  	/*
> -	 * We always have to allow these modifiers:
> -	 * 1. Core DRM checks for LINEAR support if userspace does not provide modifiers.
> -	 * 2. Not passing any modifiers is the same as explicitly passing INVALID.
> +	 * We always have to allow this modifier, because core DRM still
> +	 * checks LINEAR support if userspace does not provide modifers.
>  	 */
> -	if (modifier == DRM_FORMAT_MOD_LINEAR ||
> -	    modifier == DRM_FORMAT_MOD_INVALID) {
> +	if (modifier == DRM_FORMAT_MOD_LINEAR)
>  		return true;
> -	}
> -
> -	/* Check that the modifier is on the list of the plane's supported modifiers. */
> -	for (i = 0; i < plane->modifier_count; i++) {
> -		if (modifier == plane->modifiers[i])
> -			break;
> -	}
> -	if (i == plane->modifier_count)
> -		return false;
>  
>  	/*
>  	 * The arbitrary tiling support for multiplane formats has not been hooked
> -- 
> 2.17.1
> 

-- 
Rodrigo Siqueira
https://siqueira.tech