[Intel-gfx] [PATCH 05/16] drm/i915/gen9: Make power well disabling synchronous

[Imre Deak]

So far we only power well enabling was synchronous not disabling. Since
we don't exactly know how the firmware (both DMC and PCU) synchronizes
against the actual power well state during DC transitions, make the
disabling also synchronous.

CC: Mika Kuoppala <mika.kuoppala at linux.intel.com>
CC: Patrik Jakobsson <patrik.jakobsson at linux.intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/intel_runtime_pm.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index d20fd8f..f5f6e89 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -720,10 +720,6 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
 
 		if (!is_enabled) {
 			DRM_DEBUG_KMS("Enabling %s\n", power_well->name);
-			if (wait_for((I915_READ(HSW_PWR_WELL_DRIVER) &
-				state_mask), 1))
-				DRM_ERROR("%s enable timeout\n",
-					power_well->name);
 			check_fuse_status = true;
 		}
 	} else {
@@ -737,6 +733,11 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
 			bxt_sanitize_power_well_requests(dev_priv, power_well);
 	}
 
+	if (wait_for(!!(I915_READ(HSW_PWR_WELL_DRIVER) & state_mask) == enable,
+		     1))
+		DRM_ERROR("%s %s timeout\n",
+			  power_well->name, enable ? "enable" : "disable");
+
 	if (check_fuse_status) {
 		if (power_well->data == SKL_DISP_PW_1) {
 			if (wait_for((I915_READ(SKL_FUSE_STATUS) &
-- 
2.5.0