From f0c453dbcce7767cd868deb809ba68083c93954e Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 20 Aug 2015 12:12:32 +0100 Subject: [PATCH] iommu/arm-smmu: Ensure IAS is set correctly for AArch32-capable SMMUs AArch32-capable SMMU implementations have a minimum IAS of 40 bits, so ensure that is reflected in the stage-2 page table configuration. Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-v3.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index dafaf59dc3b8..a24f359fa0d0 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -56,6 +56,7 @@ #define IDR0_TTF_SHIFT 2 #define IDR0_TTF_MASK 0x3 #define IDR0_TTF_AARCH64 (2 << IDR0_TTF_SHIFT) +#define IDR0_TTF_AARCH32_64 (3 << IDR0_TTF_SHIFT) #define IDR0_S1P (1 << 1) #define IDR0_S2P (1 << 0) @@ -2460,7 +2461,13 @@ static int arm_smmu_device_probe(struct arm_smmu_device *smmu) } /* We only support the AArch64 table format at present */ - if ((reg & IDR0_TTF_MASK << IDR0_TTF_SHIFT) < IDR0_TTF_AARCH64) { + switch (reg & IDR0_TTF_MASK << IDR0_TTF_SHIFT) { + case IDR0_TTF_AARCH32_64: + smmu->ias = 40; + /* Fallthrough */ + case IDR0_TTF_AARCH64: + break; + default: dev_err(smmu->dev, "AArch64 table format not supported!\n"); return -ENXIO; } @@ -2541,8 +2548,7 @@ static int arm_smmu_device_probe(struct arm_smmu_device *smmu) dev_warn(smmu->dev, "failed to set DMA mask for table walker\n"); - if (!smmu->ias) - smmu->ias = smmu->oas; + smmu->ias = max(smmu->ias, smmu->oas); dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n", smmu->ias, smmu->oas, smmu->features); -- GitLab