[PATCH] drm/xe/pm: Change HPD to polling on runtime suspend

[Arun R Murthy]

HPD is interrupt based and on runtime suspend change it to polling as
HPD is not a wakeup event. A worker thread is scheduled for doing this
polling and it keeps polling for HPD live status on an internval of 10s.
On runtime resume disable polling and fallback to interrupt mechanism.

Signed-off-by: Arun R Murthy <arun.r.murthy at intel.com>
---
 drivers/gpu/drm/xe/xe_pm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
index 9f3c14fd9f33..d952b06ebfb4 100644
--- a/drivers/gpu/drm/xe/xe_pm.c
+++ b/drivers/gpu/drm/xe/xe_pm.c
@@ -22,6 +22,7 @@
 #include "xe_pcode.h"
 #include "xe_trace.h"
 #include "xe_wa.h"
+#include "intel_hotplug.h"
 
 /**
  * DOC: Xe Power Management
@@ -378,6 +379,8 @@ int xe_pm_runtime_suspend(struct xe_device *xe)
 		if (err)
 			goto out;
 	}
+	/* Enable hpd polling on runtime suspend */
+	intel_hpd_poll_enable(xe);
 
 	xe_irq_suspend(xe);
 
@@ -427,6 +430,9 @@ int xe_pm_runtime_resume(struct xe_device *xe)
 
 	xe_irq_resume(xe);
 
+	/* Disable hpd polling on runtime resume */
+	intel_hpd_poll_disable(xe);
+
 	for_each_gt(gt, xe, id)
 		xe_gt_resume(gt);
 
-- 
2.25.1