[PATCH] drm/i915/vdsc: Add bpc check in intel_dsc_compute_params

[Kandpal, Suraj]

> -----Original Message-----
> From: Borah, Chaitanya Kumar <chaitanya.kumar.borah at intel.com>
> Sent: Thursday, September 26, 2024 10:30 AM
> To: Kandpal, Suraj <suraj.kandpal at intel.com>; intel-
> gfx at lists.freedesktop.org
> Cc: Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>; Kandpal, Suraj
> <suraj.kandpal at intel.com>
> Subject: RE: [PATCH] drm/i915/vdsc: Add bpc check in
> intel_dsc_compute_params
> 
> Hello Suraj
> 
> > -----Original Message-----
> > From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of
> > Suraj Kandpal
> > Sent: Thursday, September 26, 2024 10:04 AM
> > To: intel-gfx at lists.freedesktop.org
> > Cc: Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>; Kandpal, Suraj
> > <suraj.kandpal at intel.com>
> > Subject: [PATCH] drm/i915/vdsc: Add bpc check in
> > intel_dsc_compute_params
> >
> > DSC does not support bpc under 8. Return an error if that happens to
> > be the case.
> >
> > Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_vdsc.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c
> > b/drivers/gpu/drm/i915/display/intel_vdsc.c
> > index 8158e3702ed5..39bf8bee106c 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> > @@ -297,6 +297,11 @@ int intel_dsc_compute_params(struct
> > intel_crtc_state *pipe_config)
> >
> >  	vdsc_cfg->bits_per_pixel = pipe_config->dsc.compressed_bpp_x16;
> >
> > +	if (vdsc_cfg->bites_per_pixel < 8) {

> 
> Typo: bits_per_pixel
> 
Yes that should be component

> Any Bspec link for this limitation?

In DSC1.2a under 2)requirements the input bpc can be 8,10,12,14 and 16

Regards,
Suraj Kandpal
> 
> Regards
> 
> Chaitanya
> 
> > +		drm_dbg_kms(&dev_priv->drm, "DSC bpc requirements not
> > met\n");
> > +		return -EINVAL;
> > +	}
> > +
> >  	/*
> >  	 * According to DSC 1.2 specs in Section 4.1 if native_420 is set
> >  	 * we need to double the current bpp.
> > --
> > 2.43.2