---

yaml --- r: 373567 b: refs/heads/master c: d3263bc h: refs/heads/master i: 373565: 4146a50 373563: f2eaaac 373559: 5900b7e 373551: 212879f 373535: 887dbfc 373503: 74e2e03 v: v3
git-mirror · Apr 19, 2013 · e9d709d · e9d709d
1 parent ef0b555
commit e9d709d
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Showing 2 changed files with 27 additions and 9 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7d8bfa26f236bc9528415402dda6b498a0682e42
+refs/heads/master: d3263bc29706e42f74d8800807c2dedf320d77f1
diff --git a/trunk/drivers/iommu/amd_iommu.c b/trunk/drivers/iommu/amd_iommu.c
@@ -700,14 +700,23 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
 
 static void iommu_poll_events(struct amd_iommu *iommu)
 {
-	u32 head, tail;
+	u32 head, tail, status;
 	unsigned long flags;
 
-	/* enable event interrupts again */
-	writel(MMIO_STATUS_EVT_INT_MASK, iommu->mmio_base + MMIO_STATUS_OFFSET);
-
 	spin_lock_irqsave(&iommu->lock, flags);
 
+	/* enable event interrupts again */
+	do {
+		/*
+		 * Workaround for Erratum ERBT1312
+		 * Clearing the EVT_INT bit may race in the hardware, so read
+		 * it again and make sure it was really cleared
+		 */
+		status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+		writel(MMIO_STATUS_EVT_INT_MASK,
+		       iommu->mmio_base + MMIO_STATUS_OFFSET);
+	} while (status & MMIO_STATUS_EVT_INT_MASK);
+
 	head = readl(iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
 	tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);
 
@@ -744,16 +753,25 @@ static void iommu_handle_ppr_entry(struct amd_iommu *iommu, u64 *raw)
 static void iommu_poll_ppr_log(struct amd_iommu *iommu)
 {
 	unsigned long flags;
-	u32 head, tail;
+	u32 head, tail, status;
 
 	if (iommu->ppr_log == NULL)
 		return;
 
-	/* enable ppr interrupts again */
-	writel(MMIO_STATUS_PPR_INT_MASK, iommu->mmio_base + MMIO_STATUS_OFFSET);
-
 	spin_lock_irqsave(&iommu->lock, flags);
 
+	/* enable ppr interrupts again */
+	do {
+		/*
+		 * Workaround for Erratum ERBT1312
+		 * Clearing the PPR_INT bit may race in the hardware, so read
+		 * it again and make sure it was really cleared
+		 */
+		status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+		writel(MMIO_STATUS_PPR_INT_MASK,
+		       iommu->mmio_base + MMIO_STATUS_OFFSET);
+	} while (status & MMIO_STATUS_PPR_INT_MASK);
+
 	head = readl(iommu->mmio_base + MMIO_PPR_HEAD_OFFSET);
 	tail = readl(iommu->mmio_base + MMIO_PPR_TAIL_OFFSET);