[Intel-gfx] [PATCH] drm/i915: Fix VLV DP RBR/HDMI/DAC PLL LPF coefficients

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

I just got confirmation that we're using some old values for the PLL
LPF coefficients for DP RBR/HDMI/DAC on VLV. The
VLV2A0_DP_eDP_HDMI_DPIO_driver_vbios_notes_9 document lists both values
by mistake, and apparently we had picked the wrong one. Change the
coefficients to the recommended values.

Changing the value doesn't appear to destabilize the VGA output picture
even with my sensitive HP ZR24w display. Also HDMI output to my TV still
works fine.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index fc2af13..b423432 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4448,7 +4448,7 @@ static void vlv_update_pll(struct intel_crtc *crtc)
 	    intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_ANALOG) ||
 	    intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_HDMI))
 		vlv_dpio_write(dev_priv, DPIO_LPF_COEFF(pipe),
-				 0x005f0021);
+				 0x009f0003);
 	else
 		vlv_dpio_write(dev_priv, DPIO_LPF_COEFF(pipe),
 				 0x00d0000f);
-- 
1.8.1.5