This adds support for MSI-based counter overflow interrupt.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>
Reviewed-by: Robin Murphy <robin.mur...@arm.com>
---
 drivers/perf/arm_smmuv3_pmu.c | 58 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
index c0924e5..7803e9e 100644
--- a/drivers/perf/arm_smmuv3_pmu.c
+++ b/drivers/perf/arm_smmuv3_pmu.c
@@ -67,6 +67,7 @@
 #define SMMU_PMCG_OVSSET0               0xCC0
 #define SMMU_PMCG_CFGR                  0xE00
 #define SMMU_PMCG_CFGR_SID_FILTER_TYPE  BIT(23)
+#define SMMU_PMCG_CFGR_MSI              BIT(21)
 #define SMMU_PMCG_CFGR_RELOC_CTRS       BIT(20)
 #define SMMU_PMCG_CFGR_SIZE             GENMASK(13, 8)
 #define SMMU_PMCG_CFGR_NCTR             GENMASK(5, 0)
@@ -77,6 +78,12 @@
 #define SMMU_PMCG_IRQ_CTRL              0xE50
 #define SMMU_PMCG_IRQ_CTRL_IRQEN        BIT(0)
 #define SMMU_PMCG_IRQ_CFG0              0xE58
+#define SMMU_PMCG_IRQ_CFG1              0xE60
+#define SMMU_PMCG_IRQ_CFG2              0xE64
+
+/* MSI config fields */
+#define MSI_CFG0_ADDR_MASK              GENMASK_ULL(51, 2)
+#define MSI_CFG2_MEMATTR_DEVICE_nGnRE   0x1
 
 #define SMMU_PMCG_DEFAULT_FILTER_SPAN   1
 #define SMMU_PMCG_DEFAULT_FILTER_SID    GENMASK(31, 0)
@@ -584,11 +591,62 @@ static irqreturn_t smmu_pmu_handle_irq(int irq_num, void 
*data)
        return IRQ_HANDLED;
 }
 
+static void smmu_pmu_free_msis(void *data)
+{
+       struct device *dev = data;
+
+       platform_msi_domain_free_irqs(dev);
+}
+
+static void smmu_pmu_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+       phys_addr_t doorbell;
+       struct device *dev = msi_desc_to_dev(desc);
+       struct smmu_pmu *pmu = dev_get_drvdata(dev);
+
+       doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
+       doorbell &= MSI_CFG0_ADDR_MASK;
+
+       writeq_relaxed(doorbell, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
+       writel_relaxed(msg->data, pmu->reg_base + SMMU_PMCG_IRQ_CFG1);
+       writel_relaxed(MSI_CFG2_MEMATTR_DEVICE_nGnRE,
+                      pmu->reg_base + SMMU_PMCG_IRQ_CFG2);
+}
+
+static void smmu_pmu_setup_msi(struct smmu_pmu *pmu)
+{
+       struct msi_desc *desc;
+       struct device *dev = pmu->dev;
+       int ret;
+
+       /* Clear MSI address reg */
+       writeq_relaxed(0, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
+
+       /* MSI supported or not */
+       if (!(readl(pmu->reg_base + SMMU_PMCG_CFGR) & SMMU_PMCG_CFGR_MSI))
+               return;
+
+       ret = platform_msi_domain_alloc_irqs(dev, 1, smmu_pmu_write_msi_msg);
+       if (ret) {
+               dev_warn(dev, "failed to allocate MSIs\n");
+               return;
+       }
+
+       desc = first_msi_entry(dev);
+       if (desc)
+               pmu->irq = desc->irq;
+
+       /* Add callback to free MSIs on teardown */
+       devm_add_action(dev, smmu_pmu_free_msis, dev);
+}
+
 static int smmu_pmu_setup_irq(struct smmu_pmu *pmu)
 {
        unsigned long flags = IRQF_NOBALANCING | IRQF_SHARED | IRQF_NO_THREAD;
        int irq, ret = -ENXIO;
 
+       smmu_pmu_setup_msi(pmu);
+
        irq = pmu->irq;
        if (irq)
                ret = devm_request_irq(pmu->dev, irq, smmu_pmu_handle_irq,
-- 
2.7.4


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