From: Paulo Zanoni <paulo.r.zanoni at intel.com> Because the register does not exist in gen5+. This patch solves "unclaimed register" messages on Haswell after suspend/resume. Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com> --- drivers/gpu/drm/i915/i915_suspend.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c index 63d4d30..95c0582 100644 --- a/drivers/gpu/drm/i915/i915_suspend.c +++ b/drivers/gpu/drm/i915/i915_suspend.c @@ -620,7 +620,8 @@ static void i915_save_display(struct drm_device *dev) struct drm_i915_private *dev_priv = dev->dev_private; /* Display arbitration control */ - dev_priv->regfile.saveDSPARB = I915_READ(DSPARB); + if (INTEL_INFO(dev)->gen <= 4) + dev_priv->regfile.saveDSPARB = I915_READ(DSPARB); /* This is only meaningful in non-KMS mode */ /* Don't regfile.save them in KMS mode */ @@ -707,7 +708,8 @@ static void i915_restore_display(struct drm_device *dev) struct drm_i915_private *dev_priv = dev->dev_private; /* Display arbitration */ - I915_WRITE(DSPARB, dev_priv->regfile.saveDSPARB); + if (INTEL_INFO(dev)->gen <= 4) + I915_WRITE(DSPARB, dev_priv->regfile.saveDSPARB); if (!drm_core_check_feature(dev, DRIVER_MODESET)) { /* Display port ratios (must be done before clock is set) */ -- 1.7.10.4