On Thu, Apr 10, 2025 at 10:27:45PM +0300, Laurent Pinchart wrote:
> Hi Ville,
>
> Thank you for the patch.
>
> On Thu, Apr 10, 2025 at 07:32:00PM +0300, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrj...@linux.intel.com>
> >
> > Decouple .get_format_info() from struct drm_mode_fb_cmd2 and just
> > pass the pixel format+modifier combo in by hand.
> >
> > We may want to use .get_format_info() outside of the normal
> > addfb paths where we won't have a struct drm_mode_fb_cmd2, and
> > creating a temporary one just for this seems silly.
> >
> > Cc: Harry Wentland <harry.wentl...@amd.com>
> > Cc: Leo Li <sunpeng...@amd.com>
> > Cc: Rodrigo Siqueira <sique...@igalia.com>
> > Cc: Alex Deucher <alexander.deuc...@amd.com>
> > Cc: amd-...@lists.freedesktop.org
> > Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
> > ---
> > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c | 4 ++--
> > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.h | 2 +-
> > drivers/gpu/drm/drm_fourcc.c | 3 ++-
> > drivers/gpu/drm/i915/display/intel_fb.c | 9 +++++----
> > drivers/gpu/drm/i915/display/intel_fb.h | 2 +-
> > include/drm/drm_mode_config.h | 2 +-
> > 6 files changed, 12 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> > index 3e0f45f1711c..69d715b6abd3 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> > @@ -92,9 +92,9 @@ enum dm_micro_swizzle {
> > MICRO_SWIZZLE_R = 3
> > };
> >
> > -const struct drm_format_info *amdgpu_dm_plane_get_format_info(const struct
> > drm_mode_fb_cmd2 *cmd)
> > +const struct drm_format_info *amdgpu_dm_plane_get_format_info(u32
> > pixel_format, u64 modifier)
> > {
> > - return amdgpu_lookup_format_info(cmd->pixel_format, cmd->modifier[0]);
> > + return amdgpu_lookup_format_info(pixel_format, modifier);
> > }
> >
> > void amdgpu_dm_plane_fill_blending_from_plane_state(const struct
> > drm_plane_state *plane_state,
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.h
> > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.h
> > index 615d2ab2b803..ea2619b507db 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.h
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.h
> > @@ -58,7 +58,7 @@ int amdgpu_dm_plane_init(struct amdgpu_display_manager
> > *dm,
> > unsigned long possible_crtcs,
> > const struct dc_plane_cap *plane_cap);
> >
> > -const struct drm_format_info *amdgpu_dm_plane_get_format_info(const struct
> > drm_mode_fb_cmd2 *cmd);
> > +const struct drm_format_info *amdgpu_dm_plane_get_format_info(u32
> > pixel_format, u64 modifier);
> >
> > void amdgpu_dm_plane_fill_blending_from_plane_state(const struct
> > drm_plane_state *plane_state,
> > bool *per_pixel_alpha, bool
> > *pre_multiplied_alpha,
> > diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
> > index 3a94ca211f9c..f79fff8209fd 100644
> > --- a/drivers/gpu/drm/drm_fourcc.c
> > +++ b/drivers/gpu/drm/drm_fourcc.c
> > @@ -395,7 +395,8 @@ drm_get_format_info(struct drm_device *dev,
> > const struct drm_format_info *info = NULL;
> >
> > if (dev->mode_config.funcs->get_format_info)
> > - info = dev->mode_config.funcs->get_format_info(mode_cmd);
> > + info =
> > dev->mode_config.funcs->get_format_info(mode_cmd->pixel_format,
> > +
> > mode_cmd->modifier[0]);
> >
> > if (!info)
> > info = drm_format_info(mode_cmd->pixel_format);
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.c
> > b/drivers/gpu/drm/i915/display/intel_fb.c
> > index 2b0e0f220442..b83c42fe3233 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.c
> > @@ -421,21 +421,22 @@ unsigned int intel_fb_modifier_to_tiling(u64
> > fb_modifier)
> >
> > /**
> > * intel_fb_get_format_info: Get a modifier specific format information
> > - * @cmd: FB add command structure
> > + * @pixel_format: pixel format
> > + * @modifier: modifier
> > *
> > * Returns:
> > * Returns the format information for @cmd->pixel_format specific to
> > @cmd->modifier[0],
> > * or %NULL if the modifier doesn't override the format.
>
> This needs to be updated too.
>
> > */
> > const struct drm_format_info *
> > -intel_fb_get_format_info(const struct drm_mode_fb_cmd2 *cmd)
> > +intel_fb_get_format_info(u32 pixel_format, u64 modifier)
> > {
> > - const struct intel_modifier_desc *md =
> > lookup_modifier_or_null(cmd->modifier[0]);
> > + const struct intel_modifier_desc *md =
> > lookup_modifier_or_null(modifier);
> >
> > if (!md || !md->formats)
> > return NULL;
> >
> > - return lookup_format_info(md->formats, md->format_count,
> > cmd->pixel_format);
> > + return lookup_format_info(md->formats, md->format_count, pixel_format);
> > }
> >
> > static bool plane_caps_contain_any(u8 caps, u8 mask)
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.h
> > b/drivers/gpu/drm/i915/display/intel_fb.h
> > index bdd76b372957..7d1267fbeee2 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.h
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.h
> > @@ -47,7 +47,7 @@ u64 *intel_fb_plane_get_modifiers(struct intel_display
> > *display,
> > bool intel_fb_plane_supports_modifier(struct intel_plane *plane, u64
> > modifier);
> >
> > const struct drm_format_info *
> > -intel_fb_get_format_info(const struct drm_mode_fb_cmd2 *cmd);
> > +intel_fb_get_format_info(u32 pixel_format, u64 modifier);
> >
> > bool
> > intel_format_info_is_yuv_semiplanar(const struct drm_format_info *info,
> > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
> > index 4b8f0370b79b..6fca0362bc31 100644
> > --- a/include/drm/drm_mode_config.h
> > +++ b/include/drm/drm_mode_config.h
> > @@ -95,7 +95,7 @@ struct drm_mode_config_funcs {
> > * The format information specific to the given fb metadata, or
> > * NULL if none is found.
>
> And here too. The full documentation block states
>
> /**
> * @get_format_info:
> *
> * Allows a driver to return custom format information for special
> * fb layouts (eg. ones with auxiliary compression control planes).
> *
> * RETURNS:
> *
> * The format information specific to the given fb metadata, or
> * NULL if none is found.
> */
>
> Updating the RETURNS section is easy, but the text before that is
> problematic. If the intent was to support formats with auxialiary
> compression control planes, this won't be possible anymore if we pass
> cmd->modifier[0] only. Is that an issue, or was this a foreseen use case
> that never materialized ? If we don't need to support this anymore then
> the code change is fine, and the documentation should be updated
> accordingly.
There is actually only one modifier despite having an array of
modifiers in the uapi struct. framebuffer_check() will enforce
modifier[N]==modifier[0] for all N.
--
Ville Syrjälä
Intel
