[PATCH v5 08/10] drm/xe/pm: clear PME HPD flag on runtime suspend error handler

[Vinod Govindapillai <vinod.govindapillai@intel.com>]

The HPD can generate PME flag in the intel_hotplug is set based
one PME status during early pm_runtime_suspend routine before
any IRQ reset calls and cleared during early pm_runtime_resume()
before any IRQ reset/resume calls. But in case of any error
scenario during xe_pm_runtime_suspend(), we end up in a situation
where this flag is never cleared in the "out_resume" path.

So change to global scope for intel_display_driver_pm_runtime_clear_pme()
and get it called from the error handler path as well. To have
this in cleanly, get it wrapped with corresponding xe_display wrapper.
The alternative could be to call the clear the flag from both
runtime_resume_early() and the late runtime_resume(). But the
former approach seems clean.

Assisted-by: GitHub_Copilot:claude-opus-5
Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
---
 drivers/gpu/drm/i915/display/intel_display_driver.c | 2 +-
 drivers/gpu/drm/i915/display/intel_display_driver.h | 1 +
 drivers/gpu/drm/xe/display/xe_display.c             | 9 +++++++++
 drivers/gpu/drm/xe/display/xe_display.h             | 2 ++
 drivers/gpu/drm/xe/xe_pm.c                          | 7 +++++++
 5 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c b/drivers/gpu/drm/i915/display/intel_display_driver.c
index 263eb3e08ea1..99aaceb39048 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.c
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.c
@@ -944,7 +944,7 @@ void intel_display_driver_pm_runtime_suspend_late(struct intel_display *display)
 		intel_hpd_poll_enable(display);
 }
 
-static void intel_display_driver_pm_runtime_clear_pme(struct intel_display *display)
+void intel_display_driver_pm_runtime_clear_pme(struct intel_display *display)
 {
 	intel_hpd_set_pme_capable(display, false);
 }
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.h b/drivers/gpu/drm/i915/display/intel_display_driver.h
index 1ae2ad7e95f6..51f82b6fb2f5 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.h
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.h
@@ -49,6 +49,7 @@ void intel_display_driver_runtime_pm_disable(struct intel_display *display);
 void intel_display_driver_pm_runtime_suspend(struct intel_display *display);
 void intel_display_driver_pm_runtime_suspend_late(struct intel_display *display);
 void intel_display_driver_pm_runtime_resume_early(struct intel_display *display);
+void intel_display_driver_pm_runtime_clear_pme(struct intel_display *display);
 void intel_display_driver_pm_runtime_resume(struct intel_display *display);
 
 #endif /* __INTEL_DISPLAY_DRIVER_H__ */
diff --git a/drivers/gpu/drm/xe/display/xe_display.c b/drivers/gpu/drm/xe/display/xe_display.c
index 7b25c0814674..79166aeeed85 100644
--- a/drivers/gpu/drm/xe/display/xe_display.c
+++ b/drivers/gpu/drm/xe/display/xe_display.c
@@ -409,6 +409,15 @@ void xe_display_pm_runtime_resume(struct xe_device *xe)
 	intel_display_driver_pm_runtime_resume(display);
 }
 
+void xe_display_clear_pme_hpd(struct xe_device *xe)
+{
+	struct intel_display *display = xe->display;
+
+	if (!xe->info.probe_display)
+		return;
+
+	intel_display_driver_pm_runtime_clear_pme(display);
+}
 
 static void display_device_remove(struct drm_device *dev, void *arg)
 {
diff --git a/drivers/gpu/drm/xe/display/xe_display.h b/drivers/gpu/drm/xe/display/xe_display.h
index 0babb50bfc77..92bb5ee76e06 100644
--- a/drivers/gpu/drm/xe/display/xe_display.h
+++ b/drivers/gpu/drm/xe/display/xe_display.h
@@ -45,6 +45,7 @@ void xe_display_pm_runtime_suspend(struct xe_device *xe);
 void xe_display_pm_runtime_suspend_late(struct xe_device *xe);
 void xe_display_pm_runtime_resume_early(struct xe_device *xe);
 void xe_display_pm_runtime_resume(struct xe_device *xe);
+void xe_display_clear_pme_hpd(struct xe_device *xe);
 
 #define XE_DISPLAY_DRIVER_FEATURES	(DRIVER_MODESET | DRIVER_ATOMIC)
 #define XE_DISPLAY_DRIVER_OPS						\
@@ -83,6 +84,7 @@ static inline void xe_display_pm_runtime_suspend(struct xe_device *xe) {}
 static inline void xe_display_pm_runtime_suspend_late(struct xe_device *xe) {}
 static inline void xe_display_pm_runtime_resume_early(struct xe_device *xe) {}
 static inline void xe_display_pm_runtime_resume(struct xe_device *xe) {}
+static inline void xe_display_clear_pme_hpd(struct xe_device *xe) {}
 
 #endif /* CONFIG_DRM_XE_DISPLAY */
 #endif /* _XE_DISPLAY_H_ */
diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
index c79f55b66a41..5e7263316683 100644
--- a/drivers/gpu/drm/xe/xe_pm.c
+++ b/drivers/gpu/drm/xe/xe_pm.c
@@ -663,6 +663,13 @@ int xe_pm_runtime_suspend(struct xe_device *xe)
 	return 0;
 
 out_resume:
+	/*
+	 * We need to explicitly clear the PME HPD flag in this error handler.
+	 * Normally this is set during early runtime suspend and cleared during
+	 * early runtime resume call.
+	 */
+	xe_display_clear_pme_hpd(xe);
+
 	xe_display_pm_runtime_resume(xe);
 	xe_pxp_pm_resume(xe->pxp);
 out:
-- 
2.43.0