From: Geetha Sowjanya <geethasowjanya.akula@xxxxxxxxxx>
Cavium ThunderX2 SMMU doesn't support MSI and also doesn't have unique irq
lines for gerror, eventq and cmdq-sync.
SHARED_IRQ option is set as a errata workaround, which allows to share the irq
line by register single irq handler for all the interrupts.
Signed-off-by: Geetha sowjanya <gakula@xxxxxxxxxxxxxxxxxx>
---
.../devicetree/bindings/iommu/arm,smmu-v3.txt | 5 ++
drivers/iommu/arm-smmu-v3.c | 73 ++++++++++++++++----
2 files changed, 64 insertions(+), 14 deletions(-)
diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
index 6ecc48c..44b40e0 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
@@ -55,6 +55,11 @@ the PCIe specification.
Set for Caviun ThunderX2 silicon that doesn't support
SMMU page1 register space.
+- cavium,cn9900-broken-unique-irqline
+ : Use single irq line for all the SMMUv3 interrupts.
+ Set for Caviun ThunderX2 silicon that doesn't support
+ MSI and also doesn't have unique irq lines for gerror,
+ eventq and cmdq-sync.
** Example
smmu@2b400000 {
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 2dea4a9..6c0c632 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -598,6 +598,7 @@ struct arm_smmu_device {
#define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0)
#define ARM_SMMU_OPT_PAGE0_REGS_ONLY (1 << 1)
+#define ARM_SMMU_OPT_SHARED_IRQ (1 << 2)
u32 options;
struct arm_smmu_cmdq cmdq;
@@ -665,6 +666,7 @@ struct arm_smmu_option_prop {
static struct arm_smmu_option_prop arm_smmu_options[] = {
{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
+ { ARM_SMMU_OPT_SHARED_IRQ, "cavium,cn9900-broken-unique-irqline"},
{ 0, NULL},
};
@@ -1313,6 +1315,21 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
writel(gerror, smmu->base + ARM_SMMU_GERRORN);
return IRQ_HANDLED;
}
+/* Shared irq handler*/
+static irqreturn_t arm_smmu_shared_irq_thread(int irq, void *dev)
+{
+ struct arm_smmu_device *smmu = dev;
+ irqreturn_t ret;
+
+ ret = arm_smmu_gerror_handler(irq, dev);
+ if (ret == IRQ_NONE) {
+ arm_smmu_evtq_thread(irq, dev);
+ arm_smmu_cmdq_sync_handler(irq, dev);
+ if (smmu->features & ARM_SMMU_FEAT_PRI)
+ arm_smmu_priq_thread(irq, dev);
+ }
+ return IRQ_HANDLED;
+}
/* IO_PGTABLE API */
static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
@@ -2230,18 +2247,9 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
devm_add_action(dev, arm_smmu_free_msis, dev);
}
-static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
+static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
{
- int ret, irq;
- u32 irqen_flags = IRQ_CTRL_EVTQ_IRQEN | IRQ_CTRL_GERROR_IRQEN;
-
- /* Disable IRQs first */
- ret = arm_smmu_write_reg_sync(smmu, 0, ARM_SMMU_IRQ_CTRL,
- ARM_SMMU_IRQ_CTRLACK);
- if (ret) {
- dev_err(smmu->dev, "failed to disable irqs\n");
- return ret;
- }
+ int irq, ret;
arm_smmu_setup_msis(smmu);
@@ -2284,10 +2292,46 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
if (ret < 0)
dev_warn(smmu->dev,
"failed to enable priq irq\n");
- else
- irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
}
}
+}
+
+static void arm_smmu_setup_shared_irqs(struct arm_smmu_device *smmu)
+{
+ int ret, irq;
+
+ /* Single irq is used for all queues, request single interrupt lines */
+ irq = smmu->evtq.q.irq;
+ if (irq) {
+ ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
+ arm_smmu_shared_irq_thread,
+ IRQF_ONESHOT | IRQF_SHARED,
+ "arm-smmu-v3-shared_irq", smmu);
+ if (ret < 0)
+ dev_warn(smmu->dev, "failed to enable shared irq\n");
+ }
+}
+
+static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
+{
+ int ret;
+ u32 irqen_flags = IRQ_CTRL_EVTQ_IRQEN | IRQ_CTRL_GERROR_IRQEN;
+
+ /* Disable IRQs first */
+ ret = arm_smmu_write_reg_sync(smmu, 0, ARM_SMMU_IRQ_CTRL,
+ ARM_SMMU_IRQ_CTRLACK);
+ if (ret) {
+ dev_err(smmu->dev, "failed to disable irqs\n");
+ return ret;
+ }
+
+ if (smmu->options & ARM_SMMU_OPT_SHARED_IRQ)
+ arm_smmu_setup_shared_irqs(smmu);
+ else
+ arm_smmu_setup_unique_irqs(smmu);
+
+ if (smmu->features & ARM_SMMU_FEAT_PRI)
+ irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
/* Enable interrupt generation on the SMMU */
ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
@@ -2622,7 +2666,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
static void acpi_smmu_get_options(u32 model, struct arm_smmu_device *smmu)
{
if (model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
- smmu->options |= ARM_SMMU_OPT_PAGE0_REGS_ONLY;
+ smmu->options |= ARM_SMMU_OPT_PAGE0_REGS_ONLY
+ | ARM_SMMU_OPT_SHARED_IRQ;
dev_notice(smmu->dev, "option mask 0x%x\n", smmu->options);
}
--
1.7.1
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