Commit 2f350dda authored by Simon Ser's avatar Simon Ser Committed by Alex Deucher
Browse files

drm/amdgpu: check tiling flags when creating FB on GFX8- 

On GFX9+, format modifiers are always enabled and ensure the
frame-buffers can be scanned out at ADDFB2 time.

On GFX8-, format modifiers are not supported and no other check
is performed. This means ADDFB2 IOCTLs will succeed even if the
tiling isn't supported for scan-out, and will result in garbage
displayed on screen [1].

Fix this by adding a check for tiling flags for GFX8 and older.
The check is taken from radeonsi in Mesa (see how is_displayable
is populated in gfx6_compute_surface).

Changes in v2: use drm_WARN_ONCE instead of drm_WARN (Michel)

[1]: https://github.com/swaywm/wlroots/issues/3185



Signed-off-by: default avatarSimon Ser <contact@emersion.fr>
Acked-by: default avatarMichel Dänzer <mdaenzer@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Cc: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent ce9c1d8c

drivers/gpu/drm/amd/amdgpu/amdgpu_display.c

+31 −0
Original line number Diff line number Diff line
@@ -837,6 +837,28 @@ static int convert_tiling_flags_to_modifier(struct amdgpu_framebuffer *afb) 
	return 0;

}



/* Mirrors the is_displayable check in radeonsi's gfx6_compute_surface */

static int check_tiling_flags_gfx6(struct amdgpu_framebuffer *afb)

{

	u64 micro_tile_mode;



	/* Zero swizzle mode means linear */

	if (AMDGPU_TILING_GET(afb->tiling_flags, SWIZZLE_MODE) == 0)

		return 0;



	micro_tile_mode = AMDGPU_TILING_GET(afb->tiling_flags, MICRO_TILE_MODE);

	switch (micro_tile_mode) {

	case 0: /* DISPLAY */

	case 3: /* RENDER */

		return 0;

	default:

		drm_dbg_kms(afb->base.dev,

			    "Micro tile mode %llu not supported for scanout\n",

			    micro_tile_mode);

		return -EINVAL;

	}

}



static void get_block_dimensions(unsigned int block_log2, unsigned int cpp,

				 unsigned int *width, unsigned int *height)

{
@@ -1103,6 +1125,7 @@ int amdgpu_display_framebuffer_init(struct drm_device *dev, 
				    const struct drm_mode_fb_cmd2 *mode_cmd,

				    struct drm_gem_object *obj)

{

	struct amdgpu_device *adev = drm_to_adev(dev);

	int ret, i;



	/*
@@ -1122,6 +1145,14 @@ int amdgpu_display_framebuffer_init(struct drm_device *dev, 
	if (ret)

		return ret;



	if (!dev->mode_config.allow_fb_modifiers) {

		drm_WARN_ONCE(dev, adev->family >= AMDGPU_FAMILY_AI,

			      "GFX9+ requires FB check based on format modifier\n");

		ret = check_tiling_flags_gfx6(rfb);

		if (ret)

			return ret;

	}



	if (dev->mode_config.allow_fb_modifiers &&

	    !(rfb->base.flags & DRM_MODE_FB_MODIFIERS)) {

		ret = convert_tiling_flags_to_modifier(rfb);