[Intel-gfx] [PATCH 05/19] drm/i915: Allow downscale factor of <3.0 on glk+ for all formats

[Ville Syrjälä]

On Wed, Sep 11, 2019 at 11:53:54AM +0200, Maarten Lankhorst wrote:
> Op 08-07-2019 om 14:53 schreef Ville Syrjala:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >
> > Bspec says that glk+ max downscale factor is <3.0 for all pixel formats.
> > Older platforms had a max of <2.0 for NV12. Update the code to deal with
> > this.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c | 9 ++++++---
> >  1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index ee93577bdf95..2b8a6a84605c 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -14472,7 +14472,7 @@ skl_max_scale(const struct intel_crtc_state *crtc_state,
> >  {
> >  	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
> >  	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> > -	int max_scale, mult;
> > +	int max_scale;
> >  	int crtc_clock, max_dotclk, tmpclk1, tmpclk2;
> >  
> >  	if (!crtc_state->base.enable)
> > @@ -14493,8 +14493,11 @@ skl_max_scale(const struct intel_crtc_state *crtc_state,
> >  	 *            or
> >  	 *    cdclk/crtc_clock
> >  	 */
> > -	mult = drm_format_info_is_yuv_semiplanar(format) ? 2 : 3;
> > -	tmpclk1 = (1 << 16) * mult - 1;
> > +	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv) ||
> > +	    !drm_format_info_is_yuv_semiplanar(format))
> > +		tmpclk1 = 0x30000 - 1;
> > +	else
> > +		tmpclk1 = 0x20000 - 1;
> >  	tmpclk2 = (1 << 8) * ((max_dotclk << 8) / crtc_clock);
> >  	max_scale = min(tmpclk1, tmpclk2);
> >  
> 
> For this patch and 4, 6, 7, 8:
> 
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> 
> Patch 4 seems to be exactly the same as the patch I wrote for it, so lets upstream this ASAP before someone else does as well. ;)

Almost the same, except the 'if (fourcc && ...)' part in the readout.
IIRC otherwise it would WARN when we try to look up the format info
w/ fourcc==0.

Thanks for the review.

-- 
Ville Syrjälä
Intel