[PATCH v6 3/4] drm/xe/pm: Assert on runtime suspend if VFs are enabled

[Raag Jadav <raag.jadav@intel.com>]

We hold an additional reference to the runtime PM to keep PF in D0
during VFs lifetime, as our VFs do not implement the PM capability.
This means we should never be runtime suspending as long as VFs are
enabled.

Suggested-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
---
 drivers/gpu/drm/xe/xe_pci.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
index c326430e75b5..c2939faa2296 100644
--- a/drivers/gpu/drm/xe/xe_pci.c
+++ b/drivers/gpu/drm/xe/xe_pci.c
@@ -1132,6 +1132,14 @@ static int xe_pci_runtime_suspend(struct device *dev)
 	struct xe_device *xe = pdev_to_xe_device(pdev);
 	int err;
 
+	/*
+	 * We hold an additional reference to the runtime PM to keep PF in D0
+	 * during VFs lifetime, as our VFs do not implement the PM capability.
+	 * This means we should never be runtime suspending as long as VFs are
+	 * enabled.
+	 */
+	xe_assert(xe, !pci_num_vf(pdev));
+
 	err = xe_pm_runtime_suspend(xe);
 	if (err)
 		return err;
-- 
2.34.1