[PATCH 4/6] drm/i915/pm: Move the hibernate+D3 quirk stuff into noirq() pm hooks

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

If the driver doesn't call pci_save_state() driver/pci will
normally save+power manage the device from the _noirq() pm
hooks.

We can't let that happen as some old BIOSes fail to hibernate
when the device is in D3. However, we can get a bit closer to
the standard behaviour by doing our explicit pci_save_state()
and pci_set_power_state() stuff from driver provided _noirq()
hooks as well.

This results in a change of behaviur where we no longer go
into D3 at the end of .freeze_late(), so when it comes time
to .thaw() we'll already be in D0, and thus we can drop the
explicit pci_set_power_state(D0) call.

Presumable swictcheroo suspend will want to go into D3 so
call the _noirq() stuff from the switcheroo suspend hook,
and since we dropped the pci_set_power_state(D0) from
.resume_early() we'll need to add one back into the
swtcheroo resume hook.

Cc: Bjorn Helgaas <bhelgaas at google.com>
Cc: "Rafael J. Wysocki" <rafael at kernel.org>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: linux-pci at vger.kernel.org
Cc: intel-gfx at lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_driver.c | 76 ++++++++++++++++++++----------
 1 file changed, 51 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index 1e5abf72dfc4..fe7c34045794 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -1097,6 +1097,21 @@ static int i915_drm_suspend_late(struct drm_device *dev, bool hibernation)
 
 	pci_disable_device(pdev);
 
+	return 0;
+
+fail:
+	enable_rpm_wakeref_asserts(rpm);
+	if (!dev_priv->uncore.user_forcewake_count)
+		intel_runtime_pm_driver_release(rpm);
+
+	return ret;
+}
+
+static int i915_drm_suspend_noirq(struct drm_device *dev, bool hibernation)
+{
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
+
 	/*
 	 * During hibernation on some platforms the BIOS may try to access
 	 * the device even though it's already in D3 and hang the machine. So
@@ -1117,13 +1132,6 @@ static int i915_drm_suspend_late(struct drm_device *dev, bool hibernation)
 		pci_set_power_state(pdev, PCI_D3hot);
 
 	return 0;
-
-fail:
-	enable_rpm_wakeref_asserts(rpm);
-	if (!dev_priv->uncore.user_forcewake_count)
-		intel_runtime_pm_driver_release(rpm);
-
-	return ret;
 }
 
 int i915_driver_suspend_switcheroo(struct drm_i915_private *i915,
@@ -1142,7 +1150,15 @@ int i915_driver_suspend_switcheroo(struct drm_i915_private *i915,
 	if (error)
 		return error;
 
-	return i915_drm_suspend_late(&i915->drm, false);
+	error = i915_drm_suspend_late(&i915->drm, false);
+	if (error)
+		return error;
+
+	error = i915_drm_suspend_noirq(&i915->drm, false);
+	if (error)
+		return error;
+
+	return 0;
 }
 
 static int i915_drm_resume(struct drm_device *dev)
@@ -1246,23 +1262,6 @@ static int i915_drm_resume_early(struct drm_device *dev)
 	 * similar so that power domains can be employed.
 	 */
 
-	/*
-	 * Note that we need to set the power state explicitly, since we
-	 * powered off the device during freeze and the PCI core won't power
-	 * it back up for us during thaw. Powering off the device during
-	 * freeze is not a hard requirement though, and during the
-	 * suspend/resume phases the PCI core makes sure we get here with the
-	 * device powered on. So in case we change our freeze logic and keep
-	 * the device powered we can also remove the following set power state
-	 * call.
-	 */
-	ret = pci_set_power_state(pdev, PCI_D0);
-	if (ret) {
-		drm_err(&dev_priv->drm,
-			"failed to set PCI D0 power state (%d)\n", ret);
-		return ret;
-	}
-
 	/*
 	 * Note that pci_enable_device() first enables any parent bridge
 	 * device and only then sets the power state for this device. The
@@ -1302,11 +1301,16 @@ static int i915_drm_resume_early(struct drm_device *dev)
 
 int i915_driver_resume_switcheroo(struct drm_i915_private *i915)
 {
+	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
 	int ret;
 
 	if (i915->drm.switch_power_state == DRM_SWITCH_POWER_OFF)
 		return 0;
 
+	ret = pci_set_power_state(pdev, PCI_D0);
+	if (ret)
+		return ret;
+
 	ret = i915_drm_resume_early(&i915->drm);
 	if (ret)
 		return ret;
@@ -1363,6 +1367,16 @@ static int i915_pm_suspend_late(struct device *kdev)
 	return i915_drm_suspend_late(&i915->drm, false);
 }
 
+static int i915_pm_suspend_noirq(struct device *kdev)
+{
+	struct drm_i915_private *i915 = kdev_to_i915(kdev);
+
+	if (i915->drm.switch_power_state == DRM_SWITCH_POWER_OFF)
+		return 0;
+
+	return i915_drm_suspend_noirq(&i915->drm, false);
+}
+
 static int i915_pm_poweroff_late(struct device *kdev)
 {
 	struct drm_i915_private *i915 = kdev_to_i915(kdev);
@@ -1373,6 +1387,16 @@ static int i915_pm_poweroff_late(struct device *kdev)
 	return i915_drm_suspend_late(&i915->drm, true);
 }
 
+static int i915_pm_poweroff_noirq(struct device *kdev)
+{
+	struct drm_i915_private *i915 = kdev_to_i915(kdev);
+
+	if (i915->drm.switch_power_state == DRM_SWITCH_POWER_OFF)
+		return 0;
+
+	return i915_drm_suspend_noirq(&i915->drm, true);
+}
+
 static int i915_pm_resume_early(struct device *kdev)
 {
 	struct drm_i915_private *i915 = kdev_to_i915(kdev);
@@ -1638,6 +1662,7 @@ const struct dev_pm_ops i915_pm_ops = {
 	.prepare = i915_pm_prepare,
 	.suspend = i915_pm_suspend,
 	.suspend_late = i915_pm_suspend_late,
+	.suspend_noirq = i915_pm_suspend_noirq,
 	.resume_early = i915_pm_resume_early,
 	.resume = i915_pm_resume,
 	.complete = i915_pm_complete,
@@ -1663,6 +1688,7 @@ const struct dev_pm_ops i915_pm_ops = {
 	.thaw = i915_pm_thaw,
 	.poweroff = i915_pm_suspend,
 	.poweroff_late = i915_pm_poweroff_late,
+	.poweroff_noirq = i915_pm_poweroff_noirq,
 	.restore_early = i915_pm_restore_early,
 	.restore = i915_pm_restore,
 
-- 
2.44.2