3.16.62-rc1 review patch. If anyone has any objections, please let me know.
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From: Imre Deak imre.deak@intel.com
commit 92a6803149465e2339f8f7f8f6415d75be80073d upstream.
During IPS disabling the current 42ms timeout value leads to occasional timeouts, increase it to 100ms which seems to get rid of the problem.
References: https://bugs.freedesktop.org/show_bug.cgi?id=107494 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107562 Reported-by: Diego Viola diego.viola@gmail.com Tested-by: Diego Viola diego.viola@gmail.com Cc: Diego Viola diego.viola@gmail.com Signed-off-by: Imre Deak imre.deak@intel.com Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20180905100005.7663-1-imre.dea... (cherry picked from commit acb3ef0ee40ea657280a4a11d9f60eb2937c0dca) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/gpu/drm/i915/intel_display.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3794,8 +3794,12 @@ void hsw_disable_ips(struct intel_crtc * mutex_lock(&dev_priv->rps.hw_lock); WARN_ON(sandybridge_pcode_write(dev_priv, DISPLAY_IPS_CONTROL, 0)); mutex_unlock(&dev_priv->rps.hw_lock); - /* wait for pcode to finish disabling IPS, which may take up to 42ms */ - if (wait_for((I915_READ(IPS_CTL) & IPS_ENABLE) == 0, 42)) + /* + * Wait for PCODE to finish disabling IPS. The BSpec specified + * 42ms timeout value leads to occasional timeouts so use 100ms + * instead. + */ + if (wait_for((I915_READ(IPS_CTL) & IPS_ENABLE) == 0, 100)) DRM_ERROR("Timed out waiting for IPS disable\n"); } else { I915_WRITE(IPS_CTL, 0);