drm/i915: Unify SKL cdclk init paths

Currently we initialize cdclk on SKL from two different places,
depending on whether it's during driver init or resume. Let's
unify it to happen from the same place always, and that place will be
the display core init function.

To do this we first run through the cdclk sanitation code, which will
first verify that the PLL is programmed correctly, after which we can
read out the current cdclk frequency, and once the cdclk is known we
verify that the cdclk "decimal" frequency is programmed correctly. If
any of these fail we will force a cdclk change, and to be safe we also
force the PLL to be turned off and on again. If the sanitation step
didn't notice anything amiss, we'll skip the cdclk programming which
will prevent cdclk reprogramming when the displays might be active.

We can also toss in a few WARNs about the register values into
skl_update_dpll0() since we now know that the PLL state should
always be sane when that function is called.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463172100-24715-11-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 2bee217e6ae5..3854b2ee1077 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1279,7 +1279,6 @@ void bxt_enable_dc9(struct drm_i915_private *dev_priv);
 void bxt_disable_dc9(struct drm_i915_private *dev_priv);
 void gen9_enable_dc5(struct drm_i915_private *dev_priv);
 void skl_init_cdclk(struct drm_i915_private *dev_priv);
-int skl_sanitize_cdclk(struct drm_i915_private *dev_priv);
 void skl_uninit_cdclk(struct drm_i915_private *dev_priv);
 unsigned int skl_cdclk_get_vco(unsigned int freq);
 void skl_enable_dc6(struct drm_i915_private *dev_priv);