diff options
| -rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index bdfac53dd945..96e6c41783df 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1724,6 +1724,13 @@ static void i9xx_enable_pll(struct intel_crtc *crtc) I915_READ(DPLL(!crtc->pipe)) | DPLL_DVO_2X_MODE); } + /* + * Apparently we need to have VGA mode enabled prior to changing + * the P1/P2 dividers. Otherwise the DPLL will keep using the old + * dividers, even though the register value does change. + */ + I915_WRITE(reg, 0); + I915_WRITE(reg, dpll); /* Wait for the clocks to stabilize. */ |