[PATCH] drm/i915/display: Workaround for odd panning for planar yuv

[Garg, Nemesa]

> -----Original Message-----
> From: Pottumuttu, Sai Teja <sai.teja.pottumuttu at intel.com>
> Sent: Tuesday, September 10, 2024 10:06 PM
> To: Garg, Nemesa <nemesa.garg at intel.com>; intel-xe at lists.freedesktop.org
> Subject: Re: [PATCH] drm/i915/display: Workaround for odd panning for planar
> yuv
> 
> 
> On 10-09-2024 20:07, Nemesa Garg wrote:
> > Disable the support for odd x pan for NV12 format as underrun issue is
> > seen.
> >
> > WA: 16024459452
> >
> > v2: Replace HSD with WA in commit message [Suraj]
> >      Modified the condition for handling odd panning
> >
> > v3: Simplified the condition for checking hsub
> >      Using older framework for wa as rev1[Jani]
> >
> > Signed-off-by: Nemesa Garg <nemesa.garg at intel.com>
> > ---
> >   drivers/gpu/drm/i915/display/intel_atomic_plane.c | 7 ++++++-
> >   1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > index e979786aa5cf..4afe808f128c 100644
> > --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > @@ -1029,8 +1029,13 @@ int intel_plane_check_src_coordinates(struct
> intel_plane_state *plane_state)
> >   		 * This allows NV12 and P0xx formats to have odd size and/or
> odd
> >   		 * source coordinates on DISPLAY_VER(i915) >= 20
> >   		 */
> > -		hsub = 1;
> >   		vsub = 1;
> > +		/*
> > +		 * Wa_16023981245 for display version 20.
> > +		 * Do not support odd x-panning for NV12.
> > +		 */
> > +		if (IS_LUNARLAKE(i915) && fb->format->format !=
> DRM_FORMAT_NV12)
> > +			hsub = 1;
> 1. Shouldn't it be:
> 
> if (!(IS_LUNARLAKE(i915) && fb->format->format == DRM_FORMAT_NV12))
>      hsub = 1
> Thank you Sai Teja for pointing it out.
> 2. Will you be adding the "disable even xsize" part as a separate patch?
> Will update in the same patch.
> 
> >   	} else {
> >   		hsub = fb->format->hsub;
> >   		vsub = fb->format->vsub;
> 
> Thank You
> Sai Teja