> -----Original Message-----
> From: Cavitt, Jonathan <jonathan.cav...@intel.com>
> Sent: Wednesday, September 3, 2025 4:51 AM
> To: Shankar, Uma <uma.shan...@intel.com>; intel-gfx@lists.freedesktop.org;
> intel...@lists.freedesktop.org
> Cc: ville.syrj...@linux.intel.com; Govindapillai, Vinod
> <vinod.govindapil...@intel.com>; Shankar, Uma <uma.shan...@intel.com>;
> Cavitt, Jonathan <jonathan.cav...@intel.com>
> Subject: RE: [PATCH 1/1] drm/i915/display: Remove FBC modulo 4 restriction for
> ADL+
>
> -----Original Message-----
> From: Intel-xe <intel-xe-boun...@lists.freedesktop.org> On Behalf Of Uma
> Shankar
> Sent: Tuesday, September 2, 2025 4:36 AM
> To: intel-gfx@lists.freedesktop.org; intel...@lists.freedesktop.org
> Cc: ville.syrj...@linux.intel.com; Govindapillai, Vinod
> <vinod.govindapil...@intel.com>; Shankar, Uma <uma.shan...@intel.com>
> Subject: [PATCH 1/1] drm/i915/display: Remove FBC modulo 4 restriction for
> ADL+
> >
> > FBC restriction where FBC is disabled for non-modulo 4 plane size
> > (including plane size + yoffset) is fixed from ADL onwards in h/w.
> > WA:22010751166
> >
> > Relax the restriction for the same.
> >
> > v2: Update the macro for display version check (Vinod)
> >
> > Credits-to: Vidya Srinivas <vidya.srini...@intel.com>
>
> I saw an earlier comment about how Credits-to: is not a trailer we should be
> using.
> Of the given alternatives, I'd recommend using Suggested-by.
>
Sure, will go with the same.
> > Reviewed-by: Vinod Govindapillai <vinod.govindapil...@intel.com>
>
> Reviewed-bys should go below Signed-off-bys.
Sure, will update.
> > Signed-off-by: Uma Shankar <uma.shan...@intel.com>
>
> The commit message here is the same as the commit message for the associated
> IGT patch, and all my comments there apply here as well. But for the sake of
> completeness:
>
> 1.
> s/ADL/ADL-P
>
> 2.
> The phrasing here is a bit difficult to parse and sort of implies the WA is
> the fix to
> the FBC restriction for ADL onwards, which is not the case. Try [for the
> first
> paragraph]:
>
> """
> WA:22010751166 does not apply past display version 12. Or, in other words,
> the
> FBC restriction where FBC is disabled for non-modulo 4 plane sizes (including
> plane size + yoffset) is fixed from display version 13 and onwards.
> """
Thanks for the review and feedback Jonathan, will fix and send updated version.
Regards,
Uma Shankar
> -Jonathan Cavitt
>
> > ---
> > drivers/gpu/drm/i915/display/intel_fbc.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c
> > b/drivers/gpu/drm/i915/display/intel_fbc.c
> > index d4c5deff9cbe..9e097ed80bd1 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > @@ -1550,14 +1550,14 @@ static int intel_fbc_check_plane(struct
> intel_atomic_state *state,
> > * having a Y offset that isn't divisible by 4 causes FIFO underrun
> > * and screen flicker.
> > */
> > - if (DISPLAY_VER(display) >= 9 &&
> > + if (IS_DISPLAY_VER(display, 9, 12) &&
> > plane_state->view.color_plane[0].y & 3) {
> > plane_state->no_fbc_reason = "plane start Y offset misaligned";
> > return 0;
> > }
> >
> > /* Wa_22010751166: icl, ehl, tgl, dg1, rkl */
> > - if (DISPLAY_VER(display) >= 11 &&
> > + if (IS_DISPLAY_VER(display, 9, 12) &&
> > (plane_state->view.color_plane[0].y +
> > (drm_rect_height(&plane_state->uapi.src) >> 16)) & 3) {
> > plane_state->no_fbc_reason = "plane end Y offset misaligned";
> > --
> > 2.42.0
> >
> >
