[Intel-gfx] [PATCH] drm/i915: Fix VLV DP RBR/HDMI/DAC PLL LPF coefficients

[Daniel Vetter]

On Tue, Jul 09, 2013 at 09:21:41AM -0700, Jesse Barnes wrote:
> On Fri,  5 Jul 2013 19:21:38 +0300
> ville.syrjala at linux.intel.com wrote:
> 
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > I just got confirmation that we're using some old values for the PLL
> > LPF coefficients for DP RBR/HDMI/DAC on VLV. The
> > VLV2A0_DP_eDP_HDMI_DPIO_driver_vbios_notes_9 document lists both values
> > by mistake, and apparently we had picked the wrong one. Change the
> > coefficients to the recommended values.
> > 
> > Changing the value doesn't appear to destabilize the VGA output picture
> > even with my sensitive HP ZR24w display. Also HDMI output to my TV still
> > works fine.
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_display.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > index fc2af13..b423432 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -4448,7 +4448,7 @@ static void vlv_update_pll(struct intel_crtc *crtc)
> >  	    intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_ANALOG) ||
> >  	    intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_HDMI))
> >  		vlv_dpio_write(dev_priv, DPIO_LPF_COEFF(pipe),
> > -				 0x005f0021);
> > +				 0x009f0003);
> >  	else
> >  		vlv_dpio_write(dev_priv, DPIO_LPF_COEFF(pipe),
> >  				 0x00d0000f);
> 
> Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>

Queued for -next, thanks for the patch.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch