[PATCH 07/12] drm/xe: Remove memirq status and source checks for engine interrupts

[Stuart Summers <stuart.summers@intel.com>]

For engine-specific, memory-based interrupts, hardware will not fill in
the source and status offsets, assuming that software will utilize the
vector ID to determine the destination for a particular interrupt.

GuC and VF based interrupts are still handled the same - explicitly
checking these offsets.

Bspec: 62316

Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Assisted-by: Copilot:claude-sonnet-4.6
---
 drivers/gpu/drm/xe/xe_memirq.c | 26 ++++++++------------------
 1 file changed, 8 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_memirq.c b/drivers/gpu/drm/xe/xe_memirq.c
index 9dfe965cb46e..208f44436c66 100644
--- a/drivers/gpu/drm/xe/xe_memirq.c
+++ b/drivers/gpu/drm/xe/xe_memirq.c
@@ -447,18 +447,18 @@ static void memirq_assume_received(struct xe_memirq *memirq, const char *source,
 	memirq_debug(memirq, "ASSUME %s %s(%u)\n", source, status, offset);
 }
 
-static void memirq_dispatch_engine(struct xe_memirq *memirq, struct iosys_map *status,
+static void memirq_dispatch_engine(struct xe_memirq *memirq,
 				   struct xe_hw_engine *hwe)
 {
-	memirq_debug(memirq, "STATUS %s %*ph\n", hwe->name, 16, status->vaddr);
+	memirq_debug(memirq, "dispatching engine %s\n", hwe->name);
 
 	/*
-	 * The programming note says to assume that GT_MI_USER_INTERRUPT is always
-	 * set. Check and clear related status byte just for a debug.
+	 * On MSI-X platforms hardware does not fill in the source and status
+	 * fields for engine-based interrupts (only GuC and VF interrupts have
+	 * a valid source/status). The dma-fence check for the fence completion
+	 * is opportunistic, unconditionally pass MI_USER_INTERRUPT to issue
+	 * that check.
 	 */
-	if (IS_ENABLED(CONFIG_DRM_XE_DEBUG_MEMIRQ) &&
-	    !memirq_received(memirq, status, ilog2(GT_MI_USER_INTERRUPT), hwe->name))
-		memirq_assume_received(memirq, hwe->name, ilog2(GT_MI_USER_INTERRUPT), "USER");
 	xe_hw_engine_handle_irq(hwe, GT_MI_USER_INTERRUPT);
 }
 
@@ -499,17 +499,7 @@ static void memirq_dispatch_guc(struct xe_memirq *memirq, struct iosys_map *stat
  */
 void xe_memirq_hwe_handler(struct xe_memirq *memirq, struct xe_hw_engine *hwe)
 {
-	struct iosys_map source =
-		IOSYS_MAP_INIT_OFFSET(&memirq->bo->vmap,
-				      XE_MEMIRQ_SOURCE_OFFSET(hwe->irq_page));
-
-	if (memirq_received(memirq, &source, hwe->irq_offset, "SRC")) {
-		struct iosys_map status =
-			IOSYS_MAP_INIT_OFFSET(&memirq->bo->vmap,
-					      XE_MEMIRQ_VECTOR_OFFSET(hwe->irq_page,
-								      hwe->irq_offset));
-		memirq_dispatch_engine(memirq, &status, hwe);
-	}
+	memirq_dispatch_engine(memirq, hwe);
 }
 
 /**
-- 
2.43.0