[Intel-gfx] [PATCH 2/2] drm/i915/vlv: Set D3_hot for vlv during runtime_suspend

[sagar.a.kamble at intel.com]

From: Sagar Kamble <sagar.a.kamble at intel.com>

To do a platform wide S0i3 transition, Gfx is required to go
to D3_hot state. pci_save_state and pci_restore_state needed to avoid ring
hangs across D3_hot transitions.

Cc: Daniel Vetter <daniel.vetter at ffwll.ch> (supporter:INTEL DRM DRIVERS...)
Cc: Jani Nikula <jani.nikula at linux.intel.com> (supporter:INTEL DRM DRIVERS...)
Signed-off-by: Sagar Kamble <sagar.a.kamble at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 5a08c86..70bb456 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1412,6 +1412,11 @@ static int intel_runtime_suspend(struct device *device)
 	 * via the suspend path.
 	 */
 	intel_opregion_notify_adapter(dev, PCI_D1);
+	if (IS_VALLEYVIEW(dev)) {
+		pci_save_state(pdev);
+		pci_disable_device(pdev);
+		pci_set_power_state(pdev, PCI_D3hot);
+	}
 
 	DRM_DEBUG_KMS("Device suspended\n");
 	return 0;
@@ -1428,6 +1433,12 @@ static int intel_runtime_resume(struct device *device)
 
 	DRM_DEBUG_KMS("Resuming device\n");
 
+	if (IS_VALLEYVIEW(dev)) {
+		pci_set_power_state(pdev, PCI_D0);
+		pci_restore_state(pdev);
+		pci_enable_device(pdev);
+	}
+
 	intel_opregion_notify_adapter(dev, PCI_D0);
 	dev_priv->pm.suspended = false;
 
-- 
1.8.5