iommu/arm-smmu: Add support for driver IOMMU fault handlers

Call report_iommu_fault() to allow upper-level drivers to register their
own fault handlers.
Signed-off-by: NJordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@chromium.org>
Acked-by: NWill Deacon <will@kernel.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210610214431.539029-2-robdclark@gmail.comSigned-off-by: NRob Clark <robdclark@chromium.org>

drivers/iommu/arm/arm-smmu/arm-smmu.c

@@ -408,6 +408,7 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	int idx = smmu_domain->cfg.cbndx;
+	int ret;
 
 	fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
 	if (!(fsr & ARM_SMMU_FSR_FAULT))
@@ -417,6 +418,10 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
 	iova = arm_smmu_cb_readq(smmu, idx, ARM_SMMU_CB_FAR);
 	cbfrsynra = arm_smmu_gr1_read(smmu, ARM_SMMU_GR1_CBFRSYNRA(idx));
 
+	ret = report_iommu_fault(domain, NULL, iova,
+		fsynr & ARM_SMMU_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);
+
+	if (ret == -ENOSYS)
 		dev_err_ratelimited(smmu->dev,
 		"Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cbfrsynra=0x%x, cb=%d\n",
 			    fsr, iova, fsynr, cbfrsynra, idx);