4 files changed, 95 insertions, 2 deletions
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 0e429bab436f..43db6ebe8b57 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -1879,6 +1879,8 @@ static inline int dmar_msi_reg(struct intel_iommu *iommu, int irq)
 		return DMAR_FECTL_REG;
 	else if (iommu->pr_irq == irq)
 		return DMAR_PECTL_REG;
+	else if (iommu->perf_irq == irq)
+		return DMAR_PERFINTRCTL_REG;
 	else
 		BUG();
 }
diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index d56b3c386366..d7c61eb20f6f 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -130,6 +130,8 @@
 #define DMAR_PERFCFGOFF_REG	0x310
 #define DMAR_PERFOVFOFF_REG	0x318
 #define DMAR_PERFCNTROFF_REG	0x31c
+#define DMAR_PERFINTRSTS_REG	0x324
+#define DMAR_PERFINTRCTL_REG	0x328
 #define DMAR_PERFEVNTCAP_REG	0x380
 #define DMAR_ECMD_REG		0x400
 #define DMAR_ECEO_REG		0x408
@@ -357,6 +359,9 @@
 
 #define DMA_VCS_PAS	((u64)1)
 
+/* PERFINTRSTS_REG */
+#define DMA_PERFINTRSTS_PIS	((u32)1)
+
 #define IOMMU_WAIT_OP(iommu, offset, op, cond, sts)			\
 do {									\
 	cycles_t start_time = get_cycles();				\
@@ -635,8 +640,12 @@ struct iommu_pmu {
 	struct pmu		pmu;
 	DECLARE_BITMAP(used_mask, IOMMU_PMU_IDX_MAX);
 	struct perf_event	*event_list[IOMMU_PMU_IDX_MAX];
+	unsigned char		irq_name[16];
 };
 
+#define IOMMU_IRQ_ID_OFFSET_PRQ		(DMAR_UNITS_SUPPORTED)
+#define IOMMU_IRQ_ID_OFFSET_PERF	(2 * DMAR_UNITS_SUPPORTED)
+
 struct intel_iommu {
 	void __iomem	*reg; /* Pointer to hardware regs, virtual addr */
 	u64 		reg_phys; /* physical address of hw register set */
@@ -650,7 +659,7 @@ struct intel_iommu {
 	int		seq_id;	/* sequence id of the iommu */
 	int		agaw; /* agaw of this iommu */
 	int		msagaw; /* max sagaw of this iommu */
-	unsigned int 	irq, pr_irq;
+	unsigned int	irq, pr_irq, perf_irq;
 	u16		segment;     /* PCI segment# */
 	unsigned char 	name[13];    /* Device Name */
 
diff --git a/drivers/iommu/intel/perfmon.c b/drivers/iommu/intel/perfmon.c
index 322d362b85e4..e17d9743a0d8 100644
--- a/drivers/iommu/intel/perfmon.c
+++ b/drivers/iommu/intel/perfmon.c
@@ -505,6 +505,49 @@ static void iommu_pmu_disable(struct pmu *pmu)
 	ecmd_submit_sync(iommu, DMA_ECMD_FREEZE, 0, 0);
 }
 
+static void iommu_pmu_counter_overflow(struct iommu_pmu *iommu_pmu)
+{
+	struct perf_event *event;
+	u64 status;
+	int i;
+
+	/*
+	 * Two counters may be overflowed very close. Always check
+	 * whether there are more to handle.
+	 */
+	while ((status = dmar_readq(iommu_pmu->overflow))) {
+		for_each_set_bit(i, (unsigned long *)&status, iommu_pmu->num_cntr) {
+			/*
+			 * Find the assigned event of the counter.
+			 * Accumulate the value into the event->count.
+			 */
+			event = iommu_pmu->event_list[i];
+			if (!event) {
+				pr_warn_once("Cannot find the assigned event for counter %d\n", i);
+				continue;
+			}
+			iommu_pmu_event_update(event);
+		}
+
+		dmar_writeq(iommu_pmu->overflow, status);
+	}
+}
+
+static irqreturn_t iommu_pmu_irq_handler(int irq, void *dev_id)
+{
+	struct intel_iommu *iommu = dev_id;
+
+	if (!dmar_readl(iommu->reg + DMAR_PERFINTRSTS_REG))
+		return IRQ_NONE;
+
+	iommu_pmu_counter_overflow(iommu->pmu);
+
+	/* Clear the status bit */
+	dmar_writel(iommu->reg + DMAR_PERFINTRSTS_REG, DMA_PERFINTRSTS_PIS);
+
+	return IRQ_HANDLED;
+}
+
 static int __iommu_pmu_register(struct intel_iommu *iommu)
 {
 	struct iommu_pmu *iommu_pmu = iommu->pmu;
@@ -698,6 +741,38 @@ void free_iommu_pmu(struct intel_iommu *iommu)
 	iommu->pmu = NULL;
 }
 
+static int iommu_pmu_set_interrupt(struct intel_iommu *iommu)
+{
+	struct iommu_pmu *iommu_pmu = iommu->pmu;
+	int irq, ret;
+
+	irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PERF + iommu->seq_id, iommu->node, iommu);
+	if (irq <= 0)
+		return -EINVAL;
+
+	snprintf(iommu_pmu->irq_name, sizeof(iommu_pmu->irq_name), "dmar%d-perf", iommu->seq_id);
+
+	iommu->perf_irq = irq;
+	ret = request_threaded_irq(irq, NULL, iommu_pmu_irq_handler,
+				   IRQF_ONESHOT, iommu_pmu->irq_name, iommu);
+	if (ret) {
+		dmar_free_hwirq(irq);
+		iommu->perf_irq = 0;
+		return ret;
+	}
+	return 0;
+}
+
+static void iommu_pmu_unset_interrupt(struct intel_iommu *iommu)
+{
+	if (!iommu->perf_irq)
+		return;
+
+	free_irq(iommu->perf_irq, iommu);
+	dmar_free_hwirq(iommu->perf_irq);
+	iommu->perf_irq = 0;
+}
+
 static int iommu_pmu_cpu_online(unsigned int cpu)
 {
 	if (cpumask_empty(&iommu_pmu_cpu_mask))
@@ -774,8 +849,14 @@ void iommu_pmu_register(struct intel_iommu *iommu)
 	if (iommu_pmu_cpuhp_setup(iommu_pmu))
 		goto unregister;
 
+	/* Set interrupt for overflow */
+	if (iommu_pmu_set_interrupt(iommu))
+		goto cpuhp_free;
+
 	return;
 
+cpuhp_free:
+	iommu_pmu_cpuhp_free(iommu_pmu);
 unregister:
 	perf_pmu_unregister(&iommu_pmu->pmu);
 err:
@@ -790,6 +871,7 @@ void iommu_pmu_unregister(struct intel_iommu *iommu)
 	if (!iommu_pmu)
 		return;
 
+	iommu_pmu_unset_interrupt(iommu);
 	iommu_pmu_cpuhp_free(iommu_pmu);
 	perf_pmu_unregister(&iommu_pmu->pmu);
 }
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index e7b9bedebcc0..7367f56c3bad 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -78,7 +78,7 @@ int intel_svm_enable_prq(struct intel_iommu *iommu)
 	}
 	iommu->prq = page_address(pages);
 
-	irq = dmar_alloc_hwirq(DMAR_UNITS_SUPPORTED + iommu->seq_id, iommu->node, iommu);
+	irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PRQ + iommu->seq_id, iommu->node, iommu);
 	if (irq <= 0) {
 		pr_err("IOMMU: %s: Failed to create IRQ vector for page request queue\n",
 		       iommu->name);