drm/i915: Fix port_clock and adjusted_mode.clock readout all over

Now that adjusted_mode.clock no longer contains the pixel_multiplier, we
can kill the get_clock() callback and instead do the clock readout
in get_pipe_config().

Also i9xx_crtc_clock_get() can now extract the frequency of the PCH
DPLL, so use it to populate port_clock accurately for PCH encoders.
For DP in port A the encoder is still responsible for filling in
port_clock. The FDI adjusted_mode.clock extraction is kept in place
for some extra sanity checking, but we no longer need to pretend it's
also the port_clock.

In the encoder get_config() functions fill out adjusted_mode.clock
based on port_clock and other details such as the DP M/N values,
HDMI 12bpc and SDVO pixel_multiplier. For PCH encoders we will then
do an extra sanity check to make sure the dotclock we derived from
the FDI configuratiuon matches the one we derive from port_clock.

DVO doesn't exist on PCH platforms, so it doesn't need to anything
but assign adjusted_mode.clock=port_clock. And DDI is HSW only, so
none of the changes apply there.

v2: Use hdmi_reg color format to detect 12bpc HDMI case
v3: Set adjusted_mode.clock for LVDS too
v4: Rename ironlake_crtc_clock_get to ironlake_pch_clock_get,
    eliminate the useless link_freq variable.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 831a5c021c4..05e5485a630 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -92,6 +92,7 @@ static void intel_lvds_get_config(struct intel_encoder *encoder,
 	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 lvds_reg, tmp, flags = 0;
+	int dotclock;
 
 	if (HAS_PCH_SPLIT(dev))
 		lvds_reg = PCH_LVDS;
@@ -116,6 +117,13 @@ static void intel_lvds_get_config(struct intel_encoder *encoder,
 
 		pipe_config->gmch_pfit.control |= tmp & PANEL_8TO6_DITHER_ENABLE;
 	}
+
+	dotclock = pipe_config->port_clock;
+
+	if (HAS_PCH_SPLIT(dev_priv->dev))
+		ironlake_check_encoder_dotclock(pipe_config, dotclock);
+
+	pipe_config->adjusted_mode.clock = dotclock;
 }
 
 /* The LVDS pin pair needs to be on before the DPLLs are enabled.