diff options
author | Zhenyu Wang <zhenyuw@linux.intel.com> | 2009-11-02 07:52:30 +0000 |
---|---|---|
committer | Eric Anholt <eric@anholt.net> | 2009-11-05 14:03:28 -0800 |
commit | d8a2d0e00c0d5a0d55e14b884bff034205015e51 (patch) | |
tree | 6a997424c636e447f79a09ab334b7744592ffec5 | |
parent | 4bfe6b6876a036d26a960320f1ab0bbd752c19bf (diff) |
drm/i915: HDMI hardware workaround for Ironlake
This brings some hardware workaround for HDMI port on PCH (Ibex Peak),
which fixes unstable issues like during rotation.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
-rw-r--r-- | drivers/gpu/drm/i915/intel_hdmi.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c index 663ab6de0b5..c33451aec1b 100644 --- a/drivers/gpu/drm/i915/intel_hdmi.c +++ b/drivers/gpu/drm/i915/intel_hdmi.c @@ -77,14 +77,32 @@ static void intel_hdmi_dpms(struct drm_encoder *encoder, int mode) struct intel_hdmi_priv *hdmi_priv = intel_output->dev_priv; u32 temp; - if (mode != DRM_MODE_DPMS_ON) { - temp = I915_READ(hdmi_priv->sdvox_reg); + temp = I915_READ(hdmi_priv->sdvox_reg); + + /* HW workaround, need to toggle enable bit off and on for 12bpc, but + * we do this anyway which shows more stable in testing. + */ + if (IS_IGDNG(dev)) { I915_WRITE(hdmi_priv->sdvox_reg, temp & ~SDVO_ENABLE); + POSTING_READ(hdmi_priv->sdvox_reg); + } + + if (mode != DRM_MODE_DPMS_ON) { + temp &= ~SDVO_ENABLE; } else { - temp = I915_READ(hdmi_priv->sdvox_reg); - I915_WRITE(hdmi_priv->sdvox_reg, temp | SDVO_ENABLE); + temp |= SDVO_ENABLE; } + + I915_WRITE(hdmi_priv->sdvox_reg, temp); POSTING_READ(hdmi_priv->sdvox_reg); + + /* HW workaround, need to write this twice for issue that may result + * in first write getting masked. + */ + if (IS_IGDNG(dev)) { + I915_WRITE(hdmi_priv->sdvox_reg, temp); + POSTING_READ(hdmi_priv->sdvox_reg); + } } static void intel_hdmi_save(struct drm_connector *connector) |