drm/i915: Fix mismatched INIT power domain disabling during suspend

Currently the display INIT power domain disabling/enabling happens in a
mismatched way in the suspend/resume_early hooks respectively. This can
leave display power wells incorrectly disabled in the resume hook if the
suspend sequence is aborted for some reason resulting in the
suspend/resume hooks getting called but the suspend_late/resume_early
hooks being skipped. In particular this change fixes "Unclaimed read
from register 0x1e1204" on BYT/BSW triggered from i915_drm_resume()->
intel_pps_unlock_regs_wa() when suspending with /sys/power/pm_test set
to devices.

Fixes: 85e90679335f ("drm/i915: disable power wells on suspend")
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: David Weinehall <david.weinehall@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476358446-11621-1-git-send-email-imre.deak@intel.com

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 69ff489fb683158ac7de49efca99a2201847f602..1fddc2ccada290c791033d4ff3315e519863a02d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1437,8 +1437,6 @@ static int i915_drm_suspend(struct drm_device *dev)
 
        dev_priv->suspend_count++;
 
-       intel_display_set_init_power(dev_priv, false);
-
        intel_csr_ucode_suspend(dev_priv);
 
 out:
@@ -1456,6 +1454,8 @@ static int i915_drm_suspend_late(struct drm_device *dev, bool hibernation)
 
        disable_rpm_wakeref_asserts(dev_priv);
 
+       intel_display_set_init_power(dev_priv, false);
+
        fw_csr = !IS_BROXTON(dev_priv) &&
                suspend_to_idle(dev_priv) && dev_priv->csr.dmc_payload;
        /*