It's only for the low rates that the divider value should be 0.
v2: remove unconditional write (Jesse)
check for pixel rate properly (Jesse)
v3: give up, the DAC divider apparently doesn't work, and low res modes
work ok (Jesse)
remove debug msg (Jesse)
Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
drivers/gpu/drm/i915/intel_display.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 6504337..59c2114 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4425,10 +4425,13 @@ static void vlv_update_pll(struct intel_crtc *crtc)
mdiv |= ((bestp1 << DPIO_P1_SHIFT) | (bestp2 << DPIO_P2_SHIFT));
mdiv |= ((bestn << DPIO_N_SHIFT));
mdiv |= (1 << DPIO_K_SHIFT);
- if (intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_HDMI) ||
- intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_EDP) ||
- intel_pipe_has_type(&crtc->base, INTEL_OUTPUT_DISPLAYPORT))
- mdiv |= (DPIO_POST_DIV_HDMIDP << DPIO_POST_DIV_SHIFT);
+
+ /*
+ * Post divider depends on pixel clock rate, DAC vs digital (and LVDS,
+ * but we don't support that).
+ * Note: don't use the DAC post divider as it seems unstable.
+ */
+ mdiv |= (DPIO_POST_DIV_HDMIDP << DPIO_POST_DIV_SHIFT);
intel_dpio_write(dev_priv, DPIO_DIV(pipe), mdiv);
mdiv |= DPIO_ENABLE_CALIBRATION;
--
1.7.10.4
