From 62b993a36e4c2d60669beb3d1afe038ed44a41ec Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Thu, 15 Aug 2019 19:37:36 +0100 Subject: [PATCH] iommu/arm-smmu: Add reset implementation hook Reset is an activity rife with implementation-defined poking. Add a corresponding hook, and use it to encapsulate the existing MMU-500 details. Signed-off-by: Robin Murphy Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-impl.c | 49 +++++++++++++++++++++++++++++++++++++++++++ drivers/iommu/arm-smmu.c | 39 ++++------------------------------ drivers/iommu/arm-smmu.h | 1 + 3 files changed, 54 insertions(+), 35 deletions(-) diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c index 6964179..4dc8b1c 100644 --- a/drivers/iommu/arm-smmu-impl.c +++ b/drivers/iommu/arm-smmu-impl.c @@ -4,6 +4,7 @@ #define pr_fmt(fmt) "arm-smmu: " fmt +#include #include #include "arm-smmu.h" @@ -67,6 +68,51 @@ const struct arm_smmu_impl cavium_impl = { }; +#define ARM_MMU500_ACTLR_CPRE (1 << 1) + +#define ARM_MMU500_ACR_CACHE_LOCK (1 << 26) +#define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10) +#define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8) + +static int arm_mmu500_reset(struct arm_smmu_device *smmu) +{ + u32 reg, major; + int i; + /* + * On MMU-500 r2p0 onwards we need to clear ACR.CACHE_LOCK before + * writes to the context bank ACTLRs will stick. And we just hope that + * Secure has also cleared SACR.CACHE_LOCK for this to take effect... + */ + reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7); + major = FIELD_GET(ID7_MAJOR, reg); + reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR); + if (major >= 2) + reg &= ~ARM_MMU500_ACR_CACHE_LOCK; + /* + * Allow unmatched Stream IDs to allocate bypass + * TLB entries for reduced latency. + */ + reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN; + arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg); + + /* + * Disable MMU-500's not-particularly-beneficial next-page + * prefetcher for the sake of errata #841119 and #826419. + */ + for (i = 0; i < smmu->num_context_banks; ++i) { + reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); + reg &= ~ARM_MMU500_ACTLR_CPRE; + arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg); + } + + return 0; +} + +const struct arm_smmu_impl arm_mmu500_impl = { + .reset = arm_mmu500_reset, +}; + + struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) { /* @@ -76,6 +122,9 @@ struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) * mutually-exclusive assignments. */ switch (smmu->model) { + case ARM_MMU500: + smmu->impl = &arm_mmu500_impl; + break; case CAVIUM_SMMUV2: smmu->impl = &cavium_impl; break; diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 362b6b5..fc98992 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -54,12 +54,6 @@ */ #define QCOM_DUMMY_VAL -1 -#define ARM_MMU500_ACTLR_CPRE (1 << 1) - -#define ARM_MMU500_ACR_CACHE_LOCK (1 << 26) -#define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10) -#define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8) - #define TLB_LOOP_TIMEOUT 1000000 /* 1s! */ #define TLB_SPIN_COUNT 10 @@ -1574,7 +1568,7 @@ static struct iommu_ops arm_smmu_ops = { static void arm_smmu_device_reset(struct arm_smmu_device *smmu) { int i; - u32 reg, major; + u32 reg; /* clear global FSR */ reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sGFSR); @@ -1587,38 +1581,10 @@ 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) { - /* - * Before clearing ARM_MMU500_ACTLR_CPRE, need to - * clear CACHE_LOCK bit of ACR first. And, CACHE_LOCK - * bit is only present in MMU-500r2 onwards. - */ - reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7); - major = FIELD_GET(ID7_MAJOR, reg); - reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR); - if (major >= 2) - reg &= ~ARM_MMU500_ACR_CACHE_LOCK; - /* - * Allow unmatched Stream IDs to allocate bypass - * TLB entries for reduced latency. - */ - reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN; - arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg); - } - /* Make sure all context banks are disabled and clear CB_FSR */ for (i = 0; i < smmu->num_context_banks; ++i) { arm_smmu_write_context_bank(smmu, i); arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_FSR, FSR_FAULT); - /* - * Disable MMU-500's not-particularly-beneficial next-page - * prefetcher for the sake of errata #841119 and #826419. - */ - if (smmu->model == ARM_MMU500) { - reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); - reg &= ~ARM_MMU500_ACTLR_CPRE; - arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg); - } } /* Invalidate the TLB, just in case */ @@ -1652,6 +1618,9 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu) if (smmu->features & ARM_SMMU_FEAT_EXIDS) reg |= sCR0_EXIDENABLE; + if (smmu->impl && smmu->impl->reset) + smmu->impl->reset(smmu); + /* Push the button */ arm_smmu_tlb_sync_global(smmu); arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sCR0, reg); diff --git a/drivers/iommu/arm-smmu.h b/drivers/iommu/arm-smmu.h index f4e90f3..ddafe87 100644 --- a/drivers/iommu/arm-smmu.h +++ b/drivers/iommu/arm-smmu.h @@ -288,6 +288,7 @@ struct arm_smmu_impl { void (*write_reg64)(struct arm_smmu_device *smmu, int page, int offset, u64 val); int (*cfg_probe)(struct arm_smmu_device *smmu); + int (*reset)(struct arm_smmu_device *smmu); }; static inline void __iomem *arm_smmu_page(struct arm_smmu_device *smmu, int n) -- 2.7.4