[Intel-gfx] [PATCH] drm/i915: Use the real FDI frequency for determining b/w

[Chris Wilson]

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_reg.h      |    1 +
 drivers/gpu/drm/i915/intel_display.c |    9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index c00bde7..72233fc 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2392,6 +2392,7 @@
 #define  RR_HW_HIGH_POWER_FRAMES_MASK   0xff00
 
 #define FDI_PLL_BIOS_0  0x46000
+#define  FDI_PLL_FB_CLOCK_MASK  0xf
 #define FDI_PLL_BIOS_1  0x46004
 #define FDI_PLL_BIOS_2  0x46008
 #define DISPLAY_PORT_PLL_BIOS_0         0x4600c
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 719e210..45fafe3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -342,6 +342,13 @@ static bool
 intel_find_pll_ironlake_dp(const intel_limit_t *, struct drm_crtc *crtc,
 			   int target, int refclk, intel_clock_t *best_clock);
 
+static inline u32 /* units of 100MHz */
+intel_fdi_link_freq(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	return (I915_READ(FDI_PLL_BIOS_0) & FDI_PLL_FB_CLOCK_MASK) + 2;
+}
+
 static const intel_limit_t intel_limits_i8xx_dvo = {
         .dot = { .min = I8XX_DOT_MIN,		.max = I8XX_DOT_MAX },
         .vco = { .min = I8XX_VCO_MIN,		.max = I8XX_VCO_MAX },
@@ -3667,7 +3674,7 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 				target_clock = mode->clock;
 			else
 				target_clock = adjusted_mode->clock;
-			link_bw = 270000;
+			link_bw = intel_fdi_link_freq(dev) * 10000;
 		}
 
 		/* determine panel color depth */
-- 
1.7.1