[Intel-gfx] [PATCH 2/2] drm/i915/runtime_pm: Let's avoid the undocumented D1 opregion notification.

[Rodrigo Vivi]

At least for newer generations, let's try to do the right thing that is to
notify the opregion that we are going into D3hot.

But to avoid breaking the world let's keep the older undocumented
behavior in place.

Cc: Imre Deak <imre.deak at intel.com>
Cc: Tilak Tangudu <tilak.tangudu at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/intel_runtime_pm.c | 24 ++++++++----------------
 1 file changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 43cdc2f3ff9e..371bbc58db92 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -706,27 +706,19 @@ int intel_runtime_pm_suspend(struct intel_runtime_pm *rpm)
 
 	rpm->suspended = true;
 
-	/*
-	 * FIXME: We really should find a document that references the arguments
-	 * used below!
-	 */
-	if (IS_BROADWELL(i915)) {
-		/*
-		 * On Broadwell, if we use PCI_D1 the PCH DDI ports will stop
-		 * being detected, and the call we do at intel_runtime_resume()
-		 * won't be able to restore them. Since PCI_D3hot matches the
-		 * actual specification and appears to be working, use it.
-		 */
-		intel_opregion_notify_adapter(i915, PCI_D3hot);
-	} else {
+	if (GRAPHICS_VER(i915) < 8) {
 		/*
-		 * current versions of firmware which depend on this opregion
-		 * notification have repurposed the D1 definition to mean
+		 * Some older versions of firmware which depend on this opregion
+		 * notification had repurposed the D1 definition to mean
 		 * "runtime suspended" vs. what you would normally expect (D3)
 		 * to distinguish it from notifications that might be sent via
-		 * the suspend path.
+		 * the suspend path. Unfortunately there's no documentation
+		 * available right now to justify this flow. However let's
+		 * keep for historical reasons.
 		 */
 		intel_opregion_notify_adapter(i915, PCI_D1);
+	} else {
+		intel_opregion_notify_adapter(i915, PCI_D3hot);
 	}
 
 	assert_forcewakes_inactive(&i915->uncore);
-- 
2.31.1