diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_display.c')
-rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 123cce1ae470..db4c38700951 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2814,6 +2814,46 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc, link_bw, &m_n); } + /* Ironlake: try to setup display ref clock before DPLL + * enabling. This is only under driver's control after + * PCH B stepping, previous chipset stepping should be + * ignoring this setting. + */ + if (IS_IGDNG(dev)) { + temp = I915_READ(PCH_DREF_CONTROL); + /* Always enable nonspread source */ + temp &= ~DREF_NONSPREAD_SOURCE_MASK; + temp |= DREF_NONSPREAD_SOURCE_ENABLE; + I915_WRITE(PCH_DREF_CONTROL, temp); + POSTING_READ(PCH_DREF_CONTROL); + + temp &= ~DREF_SSC_SOURCE_MASK; + temp |= DREF_SSC_SOURCE_ENABLE; + I915_WRITE(PCH_DREF_CONTROL, temp); + POSTING_READ(PCH_DREF_CONTROL); + + udelay(200); + + if (is_edp) { + if (dev_priv->lvds_use_ssc) { + temp |= DREF_SSC1_ENABLE; + I915_WRITE(PCH_DREF_CONTROL, temp); + POSTING_READ(PCH_DREF_CONTROL); + + udelay(200); + + temp &= ~DREF_CPU_SOURCE_OUTPUT_MASK; + temp |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD; + I915_WRITE(PCH_DREF_CONTROL, temp); + POSTING_READ(PCH_DREF_CONTROL); + } else { + temp |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD; + I915_WRITE(PCH_DREF_CONTROL, temp); + POSTING_READ(PCH_DREF_CONTROL); + } + } + } + if (IS_IGD(dev)) { fp = (1 << clock.n) << 16 | clock.m1 << 8 | clock.m2; if (has_reduced_clock) |