drm/i915: set the correct eDP aux channel clock divider on DDI

The cdclk frequency is not always the same, so the value here should be adjusted to match it. Version 2: call intel_ddi_get_cdclk_freq instead of reading CDCLK_FREQ, because the register is just for earlier HW steppings. Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
git-mirror · Oct 26, 2012 · b8fc2f6 · b8fc2f6
1 parent e6f0bfc
commit b8fc2f6
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Showing 3 changed files with 5 additions and 2 deletions.
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1239,7 +1239,7 @@ void intel_disable_ddi(struct intel_encoder *encoder)
 	/* This will be needed in the future, so leave it here for now */
 }
 
-static int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv)
+int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv)
 {
 	if (I915_READ(HSW_FUSE_STRAP) & HSW_CDCLK_LIMIT)
 		return 450;

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
@@ -370,7 +370,9 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 	 * clock divider.
 	 */
 	if (is_cpu_edp(intel_dp)) {
-		if (IS_VALLEYVIEW(dev))
+		if (IS_HASWELL(dev))
+			aux_clock_divider = intel_ddi_get_cdclk_freq(dev_priv) >> 1;
+		else if (IS_VALLEYVIEW(dev))
 			aux_clock_divider = 100;
 		else if (IS_GEN6(dev) || IS_GEN7(dev))
 			aux_clock_divider = 200; /* SNB & IVB eDP input clock at 400Mhz */

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
@@ -608,6 +608,7 @@ extern bool intel_ddi_get_hw_state(struct intel_encoder *encoder,
 extern void intel_ddi_mode_set(struct drm_encoder *encoder,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode);
+extern int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv);
 extern void intel_ddi_pll_init(struct drm_device *dev);
 extern void intel_ddi_enable_pipe_func(struct drm_crtc *crtc);
 extern void intel_ddi_disable_transcoder_func(struct drm_i915_private *dev_priv,