Commit d8a2d0e0 authored by Zhenyu Wang's avatar Zhenyu Wang Committed by Eric Anholt

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: default avatarZhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: default avatarEric Anholt <eric@anholt.net>
parent 4bfe6b68
......@@ -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)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment