4.18-stable review patch. If anyone has any objections, please let me know.
------------------
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 Cc: stable@vger.kernel.org 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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 @@ -5062,10 +5062,14 @@ void hsw_disable_ips(const struct intel_ mutex_lock(&dev_priv->pcu_lock); WARN_ON(sandybridge_pcode_write(dev_priv, DISPLAY_IPS_CONTROL, 0)); mutex_unlock(&dev_priv->pcu_lock); - /* wait for pcode to finish disabling IPS, which may take up to 42ms */ + /* + * Wait for PCODE to finish disabling IPS. The BSpec specified + * 42ms timeout value leads to occasional timeouts so use 100ms + * instead. + */ if (intel_wait_for_register(dev_priv, IPS_CTL, IPS_ENABLE, 0, - 42)) + 100)) DRM_ERROR("Timed out waiting for IPS disable\n"); } else { I915_WRITE(IPS_CTL, 0);