Re: [Intel-gfx] [PATCH 06/12] drm/i915: Extract intel_crtc_compute_pipe_src()

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Feb 16, 2022 at 11:35:39AM -0800, Navare, Manasi wrote:
> On Tue, Feb 15, 2022 at 08:32:02PM +0200, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > 
> > intel_crtc_compute_config() doesn't really tell a unified story.
> > Let's chunk it up into pieces. We'll start with
> > intel_crtc_compute_pipe_src().
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
> 
> with just one clarification below
> 
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c | 62 ++++++++++++--------
> >  1 file changed, 39 insertions(+), 23 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index 19417ff975c6..3d3fddd3f452 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -2798,18 +2798,55 @@ static void intel_encoder_get_config(struct intel_encoder *encoder,
> >  	intel_crtc_readout_derived_state(crtc_state);
> >  }
> >  
> > +static int intel_crtc_compute_pipe_src(struct intel_crtc_state *crtc_state)
> > +{
> > +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> > +	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> > +
> > +	if (crtc_state->bigjoiner)
> > +		crtc_state->pipe_src_w /= 2;
> > +
> > +	/*
> > +	 * Pipe horizontal size must be even in:
> > +	 * - DVO ganged mode
> > +	 * - LVDS dual channel mode
> > +	 * - Double wide pipe
> > +	 */
> > +	if (crtc_state->pipe_src_w & 1) {
> > +		if (crtc_state->double_wide) {
> > +			drm_dbg_kms(&i915->drm,
> > +				    "[CRTC:%d:%s] Odd pipe source width not supported with double wide pipe\n",
> > +				    crtc->base.base.id, crtc->base.name);
> > +			return -EINVAL;
> > +		}
> > +
> > +		if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_LVDS) &&
> > +		    intel_is_dual_link_lvds(i915)) {
> > +			drm_dbg_kms(&i915->drm,
> > +				    "[CRTC:%d:%s] Odd pipe source width not supported with dual link LVDS\n",
> > +				    crtc->base.base.id, crtc->base.name);
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  static int intel_crtc_compute_config(struct intel_crtc *crtc,
> >  				     struct intel_crtc_state *crtc_state)
> >  {
> >  	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> >  	struct drm_display_mode *pipe_mode = &crtc_state->hw.pipe_mode;
> >  	int clock_limit = i915->max_dotclk_freq;
> > +	int ret;
> > +
> > +	ret = intel_crtc_compute_pipe_src(crtc_state);
> 
> Here crtc_state->pipe_src_w would already have been populated right?
> Just wanted to double check since we are moving this earlier in the function

Yeah it's initially set up already in intel_modeset_pipe_config()
before even calling the encoder compute_config() hooks, and
intel_crtc_compute_config() gets called after those.

I'd actually prefer to calculate it completely here, but we
currently set up the panel fitter stuff already in the 
encoder->compute_config() hook. So the order has to as is,
for the moment at least.

-- 
Ville Syrjälä
Intel