Re: [Intel-gfx] [PATCH] drm/i915/psr: Remove inappropriate DSC slice alignment warning

["Souza, Jose" <jose.souza@intel.com>]

On Tue, 2022-11-01 at 20:55 +0000, Hogander, Jouni wrote:
> On Tue, 2022-11-01 at 20:00 +0000, Souza, Jose wrote:
> > On Fri, 2022-10-21 at 08:49 +0300, Jouni Högander wrote:
> > > Selective update area is now aligned with DSC slice height when
> > > DSC is enabled. Remove inappropriate warning about missing DSC
> > > alignment.
> > > 
> > > Cc: José Roberto de Souza <jose.souza@intel.com>
> > > Cc: Mika Kahola <mika.kahola@intel.com>
> > > 
> > > Fixes: 47d4ae2192cb ("drm/i915/mtl: Extend PSR support")
> > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/7212
> > > Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
> > > Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_psr.c | 3 ---
> > >  1 file changed, 3 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > > b/drivers/gpu/drm/i915/display/intel_psr.c
> > > index 904a1049eff3..64e9e134fdca 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > > @@ -1678,9 +1678,6 @@ static void
> > > intel_psr2_sel_fetch_pipe_alignment(const struct intel_crtc_state
> > > *c
> > >         pipe_clip->y1 -= pipe_clip->y1 % y_alignment;
> > >         if (pipe_clip->y2 % y_alignment)
> > >                 pipe_clip->y2 = ((pipe_clip->y2 / y_alignment) + 1)
> > > * y_alignment;
> > > -
> > > -       if (IS_ALDERLAKE_P(dev_priv) && crtc_state-
> > > > dsc.compression_enable)
> > > -               drm_warn(&dev_priv->drm, "Missing PSR2 sel fetch
> > > alignment with DSC\n");
> > 
> > It is necessary check if DSC alignment and PSR2 alignment matches, if
> > not PSR2 can't be enabled.
> 
> This check is there at the begin of
> intel_psr2_sel_fetch_pipe_alignment:
> 
> /* ADLP aligns the SU region to vdsc slice height in case dsc is
> enabled */
> if (crtc_state->dsc.compression_enable &&
> 	(IS_ALDERLAKE_P(dev_priv) || DISPLAY_VER(dev_priv) >= 14))
> 		y_alignment = vdsc_cfg->slice_height;

This is still wrong.
There is no guarantee that required PSR2 alignment matches vdsc_cfg->slice_height.

> 
> For some reason when this got merged warning was still left there. Now
> just removing the warning as well.
> 
> > 
> > >  }
> > >  
> > >  /*
> > 
>