[Intel-gfx] [PATCH] drm/i915: Support FP16 compressed formats on MTL

[Lobo, Melanie]

> -----Original Message-----
> From: Jani Nikula <jani.nikula at linux.intel.com>
> Sent: Wednesday, October 11, 2023 3:52 PM
> To: Lobo, Melanie <melanie.lobo at intel.com>; intel-gfx at lists.freedesktop.org
> Cc: Heikkila, Juha-pekka <juha-pekka.heikkila at intel.com>
> Subject: Re: [Intel-gfx] [PATCH] drm/i915: Support FP16 compressed formats
> on MTL
> 
> On Wed, 11 Oct 2023, Melanie Lobo <melanie.lobo at intel.com> wrote:
> > MTL supports FP16 format which is a binary floating-point computer
> > number format that occupies 16 bits in computer memory.Platform shall
> > render compression in display engine to receive FP16 compressed formats.
> >
> > This kernel change was tested with IGT patch,
> > https://patchwork.freedesktop.org/patch/562014/
> >
> > Test-with: 20231011095520.10768-1-melanie.lobo at intel.com
> >
> > Signed-off-by: Melanie Lobo <melanie.lobo at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_fb.c            | 2 ++
> >  drivers/gpu/drm/i915/display/skl_universal_plane.c | 3 +--
> >  2 files changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.c
> > b/drivers/gpu/drm/i915/display/intel_fb.c
> > index e7678571b0d7..868cfc75e687 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.c
> > @@ -91,6 +91,8 @@ static const struct drm_format_info
> gen12_ccs_formats[] = {
> >  	{ .format = DRM_FORMAT_P016, .num_planes = 4,
> >  	  .char_per_block = { 2, 4, 1, 1 }, .block_w = { 1, 1, 2, 2 }, .block_h = { 1,
> 1, 1, 1 },
> >  	  .hsub = 2, .vsub = 2, .is_yuv = true },
> > +	{ .format = DRM_FORMAT_XRGB16161616F, .depth = 64,
> .num_planes = 2,
> > +	  .char_per_block = { 4, 1}, .block_w = { 1, 2}, .block_h = { 1, 1},
> > +.hsub = 1, .vsub = 1 },
> >  };
> >
> >  /*
> > diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > index 245a64332cc7..64c1d6c2bd76 100644
> > --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > @@ -2122,8 +2122,7 @@ static bool
> gen12_plane_format_mod_supported(struct drm_plane *_plane,
> >  	case DRM_FORMAT_Y216:
> >  	case DRM_FORMAT_XVYU12_16161616:
> >  	case DRM_FORMAT_XVYU16161616:
> > -		if (!intel_fb_is_ccs_modifier(modifier))
> > -			return true;
> > +		return true;
> >  		fallthrough;
> 
> This becomes nop.

Thank you for your suggestion. I will float the next version by removing "fallthrough" statement.

Regards,
Melanie Lobo

> 
> BR,
> Jani.
> 
> >  	default:
> >  		return false;
> 
> --
> Jani Nikula, Intel