Re: [PATCH v15 09/10] drm/i915/display: Detect AuxCCS support via display parent interface

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Tue, Dec 09, 2025 at 11:42:35AM +0200, Ville Syrjälä wrote:
> On Mon, Dec 08, 2025 at 08:17:20PM +0100, Tvrtko Ursulin wrote:
> > From: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
> > 
> > Whether AuxCCS can be properly supported depends on the support both from
> > the display side and non-display side of the driver.
> > 
> > Let us therefore allow for the non-display part to be queried via the
> > display parent interface.
> > 
> > The new interface replaces the HAS_AUX_CCS macro and we also remove the
> > FIXME from skl_universal_plane_create since now the xe will not advertise
> > the AuxCCS caps to start with so they do not need to be removed after
> > enumeration.
> > 
> > Also, by removing this build specific FIXME we come a step closer to fully
> > de-coupling display and non-display.
> > 
> > Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
> > References: cf48bddd31de ("drm/i915/display: Disable AuxCCS framebuffers if built for Xe")
> > Cc: Jani Nikula <jani.nikula@intel.com>
> > Cc: José Roberto de Souza <jose.souza@intel.com>
> > Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display_device.h |  1 -
> >  drivers/gpu/drm/i915/display/intel_fb.c             |  3 ++-
> >  drivers/gpu/drm/i915/display/intel_parent.c         |  5 +++++
> >  drivers/gpu/drm/i915/display/intel_parent.h         |  2 ++
> >  drivers/gpu/drm/i915/display/skl_universal_plane.c  |  9 ++-------
> >  drivers/gpu/drm/i915/i915_driver.c                  | 10 ++++++++++
> >  include/drm/intel/display_parent_interface.h        |  3 +++
> >  7 files changed, 24 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h
> > index 11c2b2883f35..dc61c6560015 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_device.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_device.h
> > @@ -149,7 +149,6 @@ struct intel_display_platforms {
> >  #define HAS_4TILE(__display)		((__display)->platform.dg2 || DISPLAY_VER(__display) >= 14)
> >  #define HAS_ASYNC_FLIPS(__display)	(DISPLAY_VER(__display) >= 5)
> >  #define HAS_AS_SDP(__display)		(DISPLAY_VER(__display) >= 13)
> > -#define HAS_AUX_CCS(__display)		(IS_DISPLAY_VER(__display, 9, 12) || (__display)->platform.alderlake_p || (__display)->platform.meteorlake)
> >  #define HAS_BIGJOINER(__display)	(DISPLAY_VER(__display) >= 11 && HAS_DSC(__display))
> >  #define HAS_CASF(__display)		(DISPLAY_VER(__display) >= 20)
> >  #define HAS_CDCLK_CRAWL(__display)	(DISPLAY_INFO(__display)->has_cdclk_crawl)
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
> > index b34b4961fe1c..5b8e02ca2faf 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.c
> > @@ -21,6 +21,7 @@
> >  #include "intel_fb_bo.h"
> >  #include "intel_frontbuffer.h"
> >  #include "intel_panic.h"
> > +#include "intel_parent.h"
> >  #include "intel_plane.h"
> >  
> >  #define check_array_bounds(display, a, i) drm_WARN_ON((display)->drm, (i) >= ARRAY_SIZE(a))
> > @@ -558,7 +559,7 @@ static bool plane_has_modifier(struct intel_display *display,
> >  	 * where supported.
> >  	 */
> >  	if (intel_fb_is_ccs_modifier(md->modifier) &&
> > -	    HAS_AUX_CCS(display) != !!md->ccs.packed_aux_planes)
> > +	    intel_parent_has_auxccs(display) != !!md->ccs.packed_aux_planes)
> >  		return false;
> >  
> >  	if (md->modifier == I915_FORMAT_MOD_4_TILED_BMG_CCS &&
> > diff --git a/drivers/gpu/drm/i915/display/intel_parent.c b/drivers/gpu/drm/i915/display/intel_parent.c
> > index 2ea310cc3509..7a55def19836 100644
> > --- a/drivers/gpu/drm/i915/display/intel_parent.c
> > +++ b/drivers/gpu/drm/i915/display/intel_parent.c
> > @@ -94,3 +94,8 @@ void intel_parent_fence_priority_display(struct intel_display *display, struct d
> >  	if (display->parent->fence_priority_display)
> >  		display->parent->fence_priority_display(fence);
> >  }
> > +
> > +bool intel_parent_has_auxccs(struct intel_display *display)
> > +{
> > +	return display->parent->has_auxccs && display->parent->has_auxccs(display->drm);
> > +}
> > diff --git a/drivers/gpu/drm/i915/display/intel_parent.h b/drivers/gpu/drm/i915/display/intel_parent.h
> > index 8f91a6f75c53..f34ee81ed7a1 100644
> > --- a/drivers/gpu/drm/i915/display/intel_parent.h
> > +++ b/drivers/gpu/drm/i915/display/intel_parent.h
> > @@ -33,4 +33,6 @@ bool intel_parent_has_fenced_regions(struct intel_display *display);
> >  
> >  void intel_parent_fence_priority_display(struct intel_display *display, struct dma_fence *fence);
> >  
> > +bool intel_parent_has_auxccs(struct intel_display *display);
> > +
> >  #endif /* __INTEL_PARENT_H__ */
> > diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > index 6cd94f400e3f..7e5dce8cfec0 100644
> > --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > @@ -22,6 +22,7 @@
> >  #include "intel_fbc.h"
> >  #include "intel_frontbuffer.h"
> >  #include "intel_panic.h"
> > +#include "intel_parent.h"
> >  #include "intel_plane.h"
> >  #include "intel_psr.h"
> >  #include "intel_psr_regs.h"
> > @@ -1602,7 +1603,7 @@ icl_plane_update_noarm(struct intel_dsb *dsb,
> >  	}
> >  
> >  	/* FLAT CCS doesn't need to program AUX_DIST */
> > -	if (HAS_AUX_CCS(display))
> > +	if (intel_parent_has_auxccs(display))
> 
> This is wrong. This is also used for planar formats on
> pre-icl. I'd just leave it be so that we always write sensible
> o PLANE_AUX_DIST.

And maybe s/HAS_AUX_CCS/HAS_AUX_DIST/ or something?

-- 
Ville Syrjälä
Intel