Re: [PATCH v4 3/5] iommu/arm-smmu: Fix spurious interrupts with stall-on-fault

2025-03-05 Thread Rob Clark
On Tue, Mar 4, 2025 at 8:57 AM Connor Abbott wrote: > > On some SMMUv2 implementations, including MMU-500, SMMU_CBn_FSR.SS > asserts an interrupt. The only way to clear that bit is to resume the > transaction by writing SMMU_CBn_RESUME, but typically resuming the > transaction requires complex ope

[PATCH v4 3/5] iommu/arm-smmu: Fix spurious interrupts with stall-on-fault

2025-03-04 Thread Connor Abbott
On some SMMUv2 implementations, including MMU-500, SMMU_CBn_FSR.SS asserts an interrupt. The only way to clear that bit is to resume the transaction by writing SMMU_CBn_RESUME, but typically resuming the transaction requires complex operations (copying in pages, etc.) that can't be done in IRQ cont