[Intel-gfx] [PATCH 03/12] drm/i915: Use adjusted_mode in HDMI 12bpc clock check

[Daniel Vetter]

On Mon, Sep 02, 2013 at 10:05:26PM +0300, Ville Syrjälä wrote:
> On Mon, Sep 02, 2013 at 08:39:45PM +0200, Daniel Vetter wrote:
> > On Mon, Sep 02, 2013 at 09:13:30PM +0300, ville.syrjala at linux.intel.com wrote:
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > The pixel clock should come from adjusted_mode not requested_mode.
> > > In this case the two should be the same as we don't currently
> > > overwrite the clock in the case of HDMI. But let's make the code
> > > safe against such things happening in the future.
> > > 
> > > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > Atm only the encoder overrides the adjusted_mode at all, so I think I
> > prefer the current code flow as clearer ...
> 
> And I'd atually prefer to kill requested_mode. It's confusing.
> 
> Only hdisplay/vdisplay are always valid. Well even that's not true
> as can be seen from my double wide series.
> 
> The clock and timings can be trusted only at the very beginning of the
> compute config step. And at that point adjusted_mode contains the exact
> same information. Also apart from the clock, we never use the other
> timings from requested_mode, so keeping the whole thing around seems
> more or less pointless.

Ok, count me slightly convinced. I agree that after the pipe config
compute stage the only thing we can rely on is h/vdisplay (it's also the
only thing we actually cross-check). So I guess ditching
config->requested_mode is a good goal. If you throw a patch on top to add
a bit of documentation for the adjusted_mode and the pipe_src_h|w fields
I'll even be happy ;-)

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch