On Thu, Jun 04, 2020 at 04:44:13PM -0700, Krishna Reddy wrote: > Add global/context fault hooks to allow NVIDIA SMMU implementation > handle faults across multiple SMMUs. > > Signed-off-by: Krishna Reddy > --- > drivers/iommu/arm-smmu-nvidia.c | 100 ++++++++++++++++++++++++++++++++ > drivers/iommu/arm-smmu.c | 11 +++- > drivers/iommu/arm-smmu.h | 3 + > 3 files changed, 112 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-nvidia.c b/drivers/iommu/arm-smmu-nvidia.c > index dafc293a45217..5999b6a770992 100644 > --- a/drivers/iommu/arm-smmu-nvidia.c > +++ b/drivers/iommu/arm-smmu-nvidia.c > @@ -117,6 +117,104 @@ static int nsmmu_reset(struct arm_smmu_device *smmu) > return 0; > } > > +static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom) > +{ > + return container_of(dom, struct arm_smmu_domain, domain); > +} > + > +static irqreturn_t nsmmu_global_fault_inst(int irq, > + struct arm_smmu_device *smmu, > + int inst) > +{ > + u32 gfsr, gfsynr0, gfsynr1, gfsynr2; > + > + gfsr = readl_relaxed(nsmmu_page(smmu, inst, 0) + ARM_SMMU_GR0_sGFSR); > + gfsynr0 = readl_relaxed(nsmmu_page(smmu, inst, 0) + > + ARM_SMMU_GR0_sGFSYNR0); > + gfsynr1 = readl_relaxed(nsmmu_page(smmu, inst, 0) + > + ARM_SMMU_GR0_sGFSYNR1); > + gfsynr2 = readl_relaxed(nsmmu_page(smmu, inst, 0) + > + ARM_SMMU_GR0_sGFSYNR2); > + > + if (!gfsr) > + return IRQ_NONE; > + > + dev_err_ratelimited(smmu->dev, > + "Unexpected global fault, this could be serious\n"); > + dev_err_ratelimited(smmu->dev, > + "\tGFSR 0x%08x, GFSYNR0 0x%08x, GFSYNR1 0x%08x, GFSYNR2 0x%08x\n", > + gfsr, gfsynr0, gfsynr1, gfsynr2); > + > + writel_relaxed(gfsr, nsmmu_page(smmu, inst, 0) + ARM_SMMU_GR0_sGFSR); > + return IRQ_HANDLED; > +} > + > +static irqreturn_t nsmmu_global_fault(int irq, void *dev) > +{ > + int inst; > + irqreturn_t irq_ret = IRQ_NONE; > + struct arm_smmu_device *smmu = dev; > + > + for (inst = 0; inst < to_nvidia_smmu(smmu)->num_inst; inst++) { > + irq_ret = nsmmu_global_fault_inst(irq, smmu, inst); > + if (irq_ret == IRQ_HANDLED) > + return irq_ret; > + } > + > + return irq_ret; > +} > + > +static irqreturn_t nsmmu_context_fault_bank(int irq, > + struct arm_smmu_device *smmu, > + int idx, int inst) > +{ > + u32 fsr, fsynr, cbfrsynra; > + unsigned long iova; > + > + fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR); > + if (!(fsr & ARM_SMMU_FSR_FAULT)) > + return IRQ_NONE; > + > + fsynr = readl_relaxed(nsmmu_page(smmu, inst, smmu->numpage + idx) + > + ARM_SMMU_CB_FSYNR0); > + iova = readq_relaxed(nsmmu_page(smmu, inst, smmu->numpage + idx) + > + ARM_SMMU_CB_FAR); > + cbfrsynra = readl_relaxed(nsmmu_page(smmu, inst, 1) + > + ARM_SMMU_GR1_CBFRSYNRA(idx)); > + > + 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); > + > + writel_relaxed(fsr, nsmmu_page(smmu, inst, smmu->numpage + idx) + > + ARM_SMMU_CB_FSR); > + return IRQ_HANDLED; > +} > + > +static irqreturn_t nsmmu_context_fault(int irq, void *dev) > +{ > + int inst, idx; > + irqreturn_t irq_ret = IRQ_NONE; > + struct iommu_domain *domain = dev; > + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); > + struct arm_smmu_device *smmu = smmu_domain->smmu; > + > + for (inst = 0; inst < to_nvidia_smmu(smmu)->num_inst; inst++) { > + /* Interrupt line shared between all context faults. > + * Check for faults across all contexts. > + */ > + for (idx = 0; idx < smmu->num_context_banks; idx++) { > + irq_ret = nsmmu_context_fault_bank(irq, smmu, > + idx, inst); > + > + if (irq_ret == IRQ_HANDLED) > + return irq_ret; > + } > + } > + > + return irq_ret; > +} > + > static const struct arm_smmu_impl nvidia_smmu_impl = { > .read_reg = nsmmu_read_reg, > .write_reg = nsmmu_write_reg, > @@ -124,6 +222,8 @@ static const struct arm_smmu_impl nvidia_smmu_impl = { > .write_reg64 = nsmmu_write_reg64, > .reset = nsmmu_reset, > .tlb_sync = nsmmu_tlb_sync, > + .global_fault = nsmmu_global_fault, > + .context_fault = nsmmu_context_fault, > }; > > struct arm_smmu_device *nvidia_smmu_impl_init(struct arm_smmu_device *smmu) > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 243bc4cb2705b..d720e1e191176 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -673,6 +673,7 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, > enum io_pgtable_fmt fmt; > struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); > struct arm_smmu_cfg *cfg = &smmu_domain->cfg; > + irqreturn_t (*context_fault)(int irq, void *dev); > > mutex_lock(&smmu_domain->init_mutex); > if (smmu_domain->smmu) > @@ -835,7 +836,9 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, > * handler seeing a half-initialised domain state. > */ > irq = smmu->irqs[smmu->num_global_irqs + cfg->irptndx]; > - ret = devm_request_irq(smmu->dev, irq, arm_smmu_context_fault, > + context_fault = (smmu->impl && smmu->impl->context_fault) ? > + smmu->impl->context_fault : arm_smmu_context_fault; A simpler way might have been to assign arm_smmu_context_fault to all implementations. That way we wouldn't have to perform this check here and instead just always using smmu->impl->context_fault. > + ret = devm_request_irq(smmu->dev, irq, context_fault, > IRQF_SHARED, "arm-smmu-context-fault", domain); > if (ret < 0) { > dev_err(smmu->dev, "failed to request context IRQ %d (%u)\n", > @@ -2107,6 +2110,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > struct arm_smmu_device *smmu; > struct device *dev = &pdev->dev; > int num_irqs, i, err; > + irqreturn_t (*global_fault)(int irq, void *dev); > > smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL); > if (!smmu) { > @@ -2193,9 +2197,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > smmu->num_context_irqs = smmu->num_context_banks; > } > > + global_fault = (smmu->impl && smmu->impl->global_fault) ? > + smmu->impl->global_fault : arm_smmu_global_fault; > + Same as above. Thierry