On Mon, Sep 27, 2021 at 11:09 AM Simon Ser <contact@xxxxxxxxxxx> wrote: > > 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: Simon Ser <contact@xxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Acked-by: Michel Dänzer <mdaenzer@xxxxxxxxxx> > Cc: Alex Deucher <alexander.deucher@xxxxxxx> > Cc: Harry Wentland <hwentlan@xxxxxxx> > Cc: Nicholas Kazlauskas <Nicholas.Kazlauskas@xxxxxxx> > Cc: Bas Nieuwenhuizen <bas@xxxxxxxxxxxxxxxxxxx> Applied. Thanks. Alex > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 31 +++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c > index 58bfc7f00d76..5faf3ef28080 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c > @@ -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); > -- > 2.33.0 > >