[PATCH v4 3/3] drm/xe/guc/tlb: Flush g2h worker in case of tlb timeout

[Nirmoy Das]

Flush the g2h worker explicitly if TLB timeout happens which is
observed on LNL and that points to the recent scheduling issue with
E-cores on LNL.

This is similar to the recent fix:
commit e51527233804 ("drm/xe/guc/ct: Flush g2h worker in case of g2h
response timeout") and should be removed once there is E core
scheduling fix.

v2: Add platform check(Himal)
v3: Remove gfx platform check as the issue related to cpu
    platform(John)
    Use the common WA macro(John) and print when the flush
    resolves timeout(Matt B)

Cc: Badal Nilawar <badal.nilawar at intel.com>
Cc: Matthew Brost <matthew.brost at intel.com>
Cc: Matthew Auld <matthew.auld at intel.com>
Cc: John Harrison <John.C.Harrison at Intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
Cc: Lucas De Marchi <lucas.demarchi at intel.com>
Cc: <stable at vger.kernel.org> # v6.11+
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2687
Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
---
 drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c b/drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c
index 773de1f08db9..0bdb3ba5220a 100644
--- a/drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c
+++ b/drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c
@@ -81,6 +81,15 @@ static void xe_gt_tlb_fence_timeout(struct work_struct *work)
 		if (msecs_to_jiffies(since_inval_ms) < tlb_timeout_jiffies(gt))
 			break;
 
+		LNL_FLUSH_WORK(&gt->uc.guc.ct.g2h_worker);
+		since_inval_ms = ktime_ms_delta(ktime_get(),
+						fence->invalidation_time);
+		if (msecs_to_jiffies(since_inval_ms) < tlb_timeout_jiffies(gt)) {
+			xe_gt_dbg(gt, "LNL_FLUSH_WORK resolved TLB invalidation fence timeout, seqno=%d recv=%d",
+				  fence->seqno, gt->tlb_invalidation.seqno_recv);
+			break;
+		}
+
 		trace_xe_gt_tlb_invalidation_fence_timeout(xe, fence);
 		xe_gt_err(gt, "TLB invalidation fence timeout, seqno=%d recv=%d",
 			  fence->seqno, gt->tlb_invalidation.seqno_recv);
-- 
2.46.0