[Intel-xe] [PATCH 5/5] drm/xe: Ensure memory eviction on s2idle.

[Rodrigo Vivi]

On discrete cards we cannot allow the pci subsystem to skip
the regular suspend and we need to unblock the d3cold.

Cc: Anshuman Gupta <anshuman.gupta at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/xe/xe_pci.c | 54 ++++++++++++++++++++++---------------
 drivers/gpu/drm/xe/xe_pm.c  | 11 ++++++++
 2 files changed, 43 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
index 06759afb4224..ec4ec769a5cc 100644
--- a/drivers/gpu/drm/xe/xe_pci.c
+++ b/drivers/gpu/drm/xe/xe_pci.c
@@ -31,6 +31,28 @@ enum toggle_d3cold {
 	D3COLD_ENABLE,
 };
 
+static void d3cold_toggle(struct pci_dev *pdev, enum toggle_d3cold toggle)
+{
+	struct xe_device *xe = pdev_to_xe_device(pdev);
+	struct pci_dev *root_pdev;
+
+	if (!xe->d3cold.capable)
+		return;
+
+	root_pdev = pcie_find_root_port(pdev);
+	if (!root_pdev)
+		return;
+
+	switch (toggle) {
+	case D3COLD_DISABLE:
+		pci_d3cold_disable(root_pdev);
+		break;
+	case D3COLD_ENABLE:
+		pci_d3cold_enable(root_pdev);
+		break;
+	}
+}
+
 struct xe_subplatform_desc {
 	enum xe_subplatform subplatform;
 	const char *name;
@@ -725,6 +747,13 @@ static int xe_pci_suspend(struct device *dev)
 	if (err)
 		return err;
 
+	/*
+	 * Enabling D3Cold is needed for S2Idle/S0ix.
+	 * It is save to allow here since xe_pm_suspend has evicted
+	 * the local memory and the direct complete optimization is disabled.
+	 */
+	d3cold_toggle(pdev, D3COLD_ENABLE);
+
 	pci_save_state(pdev);
 	pci_disable_device(pdev);
 
@@ -740,6 +769,9 @@ static int xe_pci_resume(struct device *dev)
 	struct pci_dev *pdev = to_pci_dev(dev);
 	int err;
 
+	/* Give back the D3Cold decision to the runtime P M*/
+	d3cold_toggle(pdev, D3COLD_DISABLE);
+
 	err = pci_set_power_state(pdev, PCI_D0);
 	if (err)
 		return err;
@@ -759,28 +791,6 @@ static int xe_pci_resume(struct device *dev)
 	return 0;
 }
 
-static void d3cold_toggle(struct pci_dev *pdev, enum toggle_d3cold toggle)
-{
-	struct xe_device *xe = pdev_to_xe_device(pdev);
-	struct pci_dev *root_pdev;
-
-	if (!xe->d3cold.capable)
-		return;
-
-	root_pdev = pcie_find_root_port(pdev);
-	if (!root_pdev)
-		return;
-
-	switch (toggle) {
-	case D3COLD_DISABLE:
-		pci_d3cold_disable(root_pdev);
-		break;
-	case D3COLD_ENABLE:
-		pci_d3cold_enable(root_pdev);
-		break;
-	}
-}
-
 static int xe_pci_runtime_suspend(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
index 67ca7cb7e8dd..8bb8e154e5f8 100644
--- a/drivers/gpu/drm/xe/xe_pm.c
+++ b/drivers/gpu/drm/xe/xe_pm.c
@@ -139,6 +139,17 @@ static void xe_pm_runtime_init(struct xe_device *xe)
 {
 	struct device *dev = xe->drm.dev;
 
+	/*
+	 * Disable the system suspend direct complete optimization.
+	 * We need to ensure that the regular device suspend/resume functions
+	 * are called since our runtime_pm cannot guarantee local memory
+	 * eviction for d3cold.
+	 * TODO: Check HDA audio dependencies claimed by i915, and then enforce
+	 *       this option to integrated graphics as well.
+	 */
+	if (IS_DGFX(xe))
+		dev_pm_set_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE);
+
 	pm_runtime_use_autosuspend(dev);
 	pm_runtime_set_autosuspend_delay(dev, 1000);
 	pm_runtime_set_active(dev);
-- 
2.41.0