drm/i915/bdw: get the correct LCPLL frequency on Broadwell

v2: Rebased onto Paulo's MHz->kHz change.

v3: Rebased on top of the Haswell pc8+ adjustements.

v4: Use the exact 337.5MHz clock, should have been done as part of v2.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> (v1)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

2 files changed, 21 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index a4a41f5df469..0b7983b87ce8 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5315,6 +5315,9 @@
 #define  LCPLL_PLL_LOCK                 (1<<30)
 #define  LCPLL_CLK_FREQ_MASK            (3<<26)
 #define  LCPLL_CLK_FREQ_450             (0<<26)
+#define  LCPLL_CLK_FREQ_54O_BDW         (1<<26)
+#define  LCPLL_CLK_FREQ_337_5_BDW       (2<<26)
+#define  LCPLL_CLK_FREQ_675_BDW         (3<<26)
 #define  LCPLL_CD_CLOCK_DISABLE         (1<<25)
 #define  LCPLL_CD2X_CLOCK_DISABLE       (1<<23)
 #define  LCPLL_POWER_DOWN_ALLOW         (1<<22)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 0598669f84e8..060add6468ec 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1158,18 +1158,29 @@ static void intel_disable_ddi(struct intel_encoder *intel_encoder)
 
 int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv)
 {
+        struct drm_device *dev = dev_priv->dev;
         uint32_t lcpll = I915_READ(LCPLL_CTL);
+        uint32_t freq = lcpll & LCPLL_CLK_FREQ_MASK;
 
-        if (lcpll & LCPLL_CD_SOURCE_FCLK)
+        if (lcpll & LCPLL_CD_SOURCE_FCLK) {
                 return 800000;
-        else if (I915_READ(HSW_FUSE_STRAP) & HSW_CDCLK_LIMIT)
+        } else if (I915_READ(HSW_FUSE_STRAP) & HSW_CDCLK_LIMIT) {
                 return 450000;
-        else if ((lcpll & LCPLL_CLK_FREQ_MASK) == LCPLL_CLK_FREQ_450)
+        } else if (freq == LCPLL_CLK_FREQ_450) {
                 return 450000;
-        else if (IS_ULT(dev_priv->dev))
-                return 337500;
-        else
-                return 540000;
+        } else if (IS_HASWELL(dev)) {
+                if (IS_ULT(dev))
+                        return 337500;
+                else
+                        return 540000;
+        } else {
+                if (freq == LCPLL_CLK_FREQ_54O_BDW)
+                        return 540000;
+                else if (freq == LCPLL_CLK_FREQ_337_5_BDW)
+                        return 337500;
+                else
+                        return 675000;
+        }
 }
 
 void intel_ddi_pll_init(struct drm_device *dev)