[Intel-gfx] [PATCH v3] drm/i915/psr: Update PSR2 resolution check for Cannonlake

[Pandiyan, Dhinakaran]

On Tue, 2018-03-06 at 22:38 +0200, Ville Syrjälä wrote:
> On Tue, Mar 06, 2018 at 12:33:55PM -0800, Dhinakaran Pandiyan wrote:
> > In fact, apply the Cannonlake resolution check for all >= Gen-10 platforms
> > to be safe.
> > 
> > v3: Update GLK too. (Ville)
> >     Longer variable names.
> >     if-else in place of ternary operator.
> > v2: Use local variables for resolution limits and print them (Ville)
> > 
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > Cc: Elio Martinez Monroy <elio.martinez.monroy at intel.com>
> > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_psr.c | 21 +++++++++++++++------
> >  1 file changed, 15 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
> > index 05770790a4e9..23175c5c4a50 100644
> > --- a/drivers/gpu/drm/i915/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/intel_psr.c
> > @@ -451,8 +451,9 @@ static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
> >  {
> >  	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> >  	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> > -	const struct drm_display_mode *adjusted_mode =
> > -		&crtc_state->base.adjusted_mode;
> > +	int crtc_hdisplay = crtc_state->base.adjusted_mode.crtc_hdisplay;
> > +	int crtc_vdisplay = crtc_state->base.adjusted_mode.crtc_vdisplay;
>             ^^^^^
> The crtc_ prefix is pretty much redundant.

display_mode has members named vdisplay and hdisplay and this avoids any
potential confusion.


> 
> > +	int psr_max_h = 0, psr_max_v = 0;
> 
> And this still reads as "max height" to my brain, but meh.

And here I thought this version leaves no room for confusion :) I should
just ask someone else to write this patch.

> 
> >  
> >  	/*
> >  	 * FIXME psr2_support is messed up. It's both computed
> > @@ -462,10 +463,18 @@ static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
> >  	if (!dev_priv->psr.psr2_support)
> >  		return false;
> >  
> > -	/* PSR2 is restricted to work with panel resolutions up to 3640x2304 */
> > -	if (adjusted_mode->crtc_hdisplay > 3640 ||
> > -	    adjusted_mode->crtc_vdisplay > 2304) {
> > -		DRM_DEBUG_KMS("PSR2 not enabled, panel resolution too big\n");
> > +	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) {
> > +		psr_max_h = 4096;
> > +		psr_max_v = 2304;
> > +	} else if (IS_GEN9(dev_priv)) {
> > +		psr_max_h = 3640;
> > +		psr_max_v = 2304;
> > +	}
> 
> pre-SKL?

No PSR2 on pre-skl

If we do somehow end up here, returning false and printing a debug
message will be useful.

> 
> > +
> > +	if (crtc_hdisplay > psr_max_h || crtc_vdisplay > psr_max_v) {
> > +		DRM_DEBUG_KMS("PSR2 not enabled, resolution %dx%d > max supported %dx%d\n",
> > +			      crtc_hdisplay, crtc_vdisplay,
> > +			      psr_max_h, psr_max_v);
> >  		return false;
> >  	}
> >  
> > -- 
> > 2.14.1
>