From: Hanna Hawa <hannah@xxxxxxxxxxx> Due to erratum #582743, the Marvell Armada-AP806 can't access 64bit to ARM SMMUv2 registers. This patch split the writeq/readq to two accesses of writel/readl. We also mask the MMU_IDR2.PTFSv8 fields to not use AArch64 format but only AARCH32_L. Indeed with AArch64 format 32 bits acces is not supported. Note that separate writes/reads to 2 is not problem regards to atomicity, because the driver use the readq/writeq while initialize the SMMU, report for SMMU fault, and use spinlock in one case (iova_to_phys). Signed-off-by: Hanna Hawa <hannah@xxxxxxxxxxx> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx> --- Documentation/arm64/silicon-errata.txt | 2 ++ drivers/iommu/arm-smmu.c | 42 +++++++++++++++++++++++--- 2 files changed, 40 insertions(+), 4 deletions(-) diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index d1e2bb801e1b..3f78ae7a7690 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -72,6 +72,8 @@ stable kernels. | Cavium | ThunderX2 SMMUv3| #74 | N/A | | Cavium | ThunderX2 SMMUv3| #126 | N/A | | | | | | +| Marvell | ARM-MMU-500 | #582743 | N/A | +| | | | | | Freescale/NXP | LS2080A/LS1043A | A-008585 | FSL_ERRATUM_A008585 | | | | | | | Hisilicon | Hip0{5,6,7} | #161010101 | HISILICON_ERRATUM_161010101 | diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index ac0784b5b675..32536ccae22d 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -126,6 +126,7 @@ enum arm_smmu_arch_version { enum arm_smmu_implementation { GENERIC_SMMU, ARM_MMU500, + MRVL_MMU500, CAVIUM_SMMUV2, QCOM_SMMUV2, }; @@ -301,13 +302,35 @@ static inline void smmu_writeq_relaxed(struct arm_smmu_device *smmu, u64 val, void __iomem *addr) { - writeq_relaxed(val, addr); + /* + * Marvell Armada-AP806 erratum #582743. + * Split all the writeq to double writel + */ + if (smmu->model != MRVL_MMU500) { + writeq_relaxed(val, addr); + return; + } + + writel_relaxed(upper_32_bits(val), addr + 4); + writel_relaxed(lower_32_bits(val), addr); } static inline u64 smmu_readq_relaxed(struct arm_smmu_device *smmu, void __iomem *addr) { - return readq_relaxed(addr); + u64 val; + + /* + * Marvell Armada-AP806 erratum #582743. + * Split all the readq to double readl + */ + if (smmu->model != MRVL_MMU500) + return readq_relaxed(addr); + + val = (u64)readl_relaxed(addr + 4) << 32; + val |= readl_relaxed(addr); + + return val; } static void parse_driver_options(struct arm_smmu_device *smmu) @@ -1741,7 +1764,7 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu) for (i = 0; i < smmu->num_mapping_groups; ++i) arm_smmu_write_sme(smmu, i); - if (smmu->model == ARM_MMU500) { + if (smmu->model == ARM_MMU500 || smmu->model == MRVL_MMU500) { /* * Before clearing ARM_MMU500_ACTLR_CPRE, need to * clear CACHE_LOCK bit of ACR first. And, CACHE_LOCK @@ -1770,7 +1793,7 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu) * Disable MMU-500's not-particularly-beneficial next-page * prefetcher for the sake of errata #841119 and #826419. */ - if (smmu->model == ARM_MMU500) { + if (smmu->model == ARM_MMU500 || smmu->model == MRVL_MMU500) { reg = readl_relaxed(cb_base + ARM_SMMU_CB_ACTLR); reg &= ~ARM_MMU500_ACTLR_CPRE; writel_relaxed(reg, cb_base + ARM_SMMU_CB_ACTLR); @@ -1987,6 +2010,15 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) if (id & ID2_VMID16) smmu->features |= ARM_SMMU_FEAT_VMID16; + /* + * Armada-AP806 erratum #582743. + * Hide the SMMU_IDR2.PTFSv8 fields to sidestep the AArch64 + * formats altogether and allow using 32 bits access on the + * interconnect. + */ + if (smmu->model == MRVL_MMU500) + id &= ~(ID2_PTFS_4K | ID2_PTFS_16K | ID2_PTFS_64K); + /* * What the page table walker can address actually depends on which * descriptor format is in use, but since a) we don't know that yet, @@ -2053,6 +2085,7 @@ ARM_SMMU_MATCH_DATA(smmu_generic_v1, ARM_SMMU_V1, GENERIC_SMMU); ARM_SMMU_MATCH_DATA(smmu_generic_v2, ARM_SMMU_V2, GENERIC_SMMU); ARM_SMMU_MATCH_DATA(arm_mmu401, ARM_SMMU_V1_64K, GENERIC_SMMU); ARM_SMMU_MATCH_DATA(arm_mmu500, ARM_SMMU_V2, ARM_MMU500); +ARM_SMMU_MATCH_DATA(mrvl_mmu500, ARM_SMMU_V2, MRVL_MMU500); ARM_SMMU_MATCH_DATA(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2); ARM_SMMU_MATCH_DATA(qcom_smmuv2, ARM_SMMU_V2, QCOM_SMMUV2); @@ -2062,6 +2095,7 @@ static const struct of_device_id arm_smmu_of_match[] = { { .compatible = "arm,mmu-400", .data = &smmu_generic_v1 }, { .compatible = "arm,mmu-401", .data = &arm_mmu401 }, { .compatible = "arm,mmu-500", .data = &arm_mmu500 }, + { .compatible = "marvell,mmu-500", .data = &mrvl_mmu500 }, { .compatible = "cavium,smmu-v2", .data = &cavium_smmuv2 }, { .compatible = "qcom,smmu-v2", .data = &qcom_smmuv2 }, { }, -- 2.20.1