1 // SPDX-License-Identifier: GPL-2.0-only 2 // Miscellaneous Arm SMMU implementation and integration quirks 3 // Copyright (C) 2019 Arm Limited 4 5 #define pr_fmt(fmt) "arm-smmu: " fmt 6 7 #include <linux/bitfield.h> 8 #include <linux/of.h> 9 10 #include "arm-smmu.h" 11 12 13 static int arm_smmu_gr0_ns(int offset) 14 { 15 switch (offset) { 16 case ARM_SMMU_GR0_sCR0: 17 case ARM_SMMU_GR0_sACR: 18 case ARM_SMMU_GR0_sGFSR: 19 case ARM_SMMU_GR0_sGFSYNR0: 20 case ARM_SMMU_GR0_sGFSYNR1: 21 case ARM_SMMU_GR0_sGFSYNR2: 22 return offset + 0x400; 23 default: 24 return offset; 25 } 26 } 27 28 static u32 arm_smmu_read_ns(struct arm_smmu_device *smmu, int page, 29 int offset) 30 { 31 if (page == ARM_SMMU_GR0) 32 offset = arm_smmu_gr0_ns(offset); 33 return readl_relaxed(arm_smmu_page(smmu, page) + offset); 34 } 35 36 static void arm_smmu_write_ns(struct arm_smmu_device *smmu, int page, 37 int offset, u32 val) 38 { 39 if (page == ARM_SMMU_GR0) 40 offset = arm_smmu_gr0_ns(offset); 41 writel_relaxed(val, arm_smmu_page(smmu, page) + offset); 42 } 43 44 /* Since we don't care for sGFAR, we can do without 64-bit accessors */ 45 static const struct arm_smmu_impl calxeda_impl = { 46 .read_reg = arm_smmu_read_ns, 47 .write_reg = arm_smmu_write_ns, 48 }; 49 50 51 struct cavium_smmu { 52 struct arm_smmu_device smmu; 53 u32 id_base; 54 }; 55 56 static int cavium_cfg_probe(struct arm_smmu_device *smmu) 57 { 58 static atomic_t context_count = ATOMIC_INIT(0); 59 struct cavium_smmu *cs = container_of(smmu, struct cavium_smmu, smmu); 60 /* 61 * Cavium CN88xx erratum #27704. 62 * Ensure ASID and VMID allocation is unique across all SMMUs in 63 * the system. 64 */ 65 cs->id_base = atomic_fetch_add(smmu->num_context_banks, &context_count); 66 dev_notice(smmu->dev, "\tenabling workaround for Cavium erratum 27704\n"); 67 68 return 0; 69 } 70 71 static int cavium_init_context(struct arm_smmu_domain *smmu_domain, 72 struct io_pgtable_cfg *pgtbl_cfg, struct device *dev) 73 { 74 struct cavium_smmu *cs = container_of(smmu_domain->smmu, 75 struct cavium_smmu, smmu); 76 77 if (smmu_domain->stage == ARM_SMMU_DOMAIN_S2) 78 smmu_domain->cfg.vmid += cs->id_base; 79 else 80 smmu_domain->cfg.asid += cs->id_base; 81 82 return 0; 83 } 84 85 static const struct arm_smmu_impl cavium_impl = { 86 .cfg_probe = cavium_cfg_probe, 87 .init_context = cavium_init_context, 88 }; 89 90 static struct arm_smmu_device *cavium_smmu_impl_init(struct arm_smmu_device *smmu) 91 { 92 struct cavium_smmu *cs; 93 94 cs = devm_krealloc(smmu->dev, smmu, sizeof(*cs), GFP_KERNEL); 95 if (!cs) 96 return ERR_PTR(-ENOMEM); 97 98 cs->smmu.impl = &cavium_impl; 99 100 return &cs->smmu; 101 } 102 103 104 #define ARM_MMU500_ACTLR_CPRE (1 << 1) 105 106 #define ARM_MMU500_ACR_CACHE_LOCK (1 << 26) 107 #define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10) 108 #define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8) 109 110 int arm_mmu500_reset(struct arm_smmu_device *smmu) 111 { 112 u32 reg, major; 113 int i; 114 /* 115 * On MMU-500 r2p0 onwards we need to clear ACR.CACHE_LOCK before 116 * writes to the context bank ACTLRs will stick. And we just hope that 117 * Secure has also cleared SACR.CACHE_LOCK for this to take effect... 118 */ 119 reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7); 120 major = FIELD_GET(ARM_SMMU_ID7_MAJOR, reg); 121 reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR); 122 if (major >= 2) 123 reg &= ~ARM_MMU500_ACR_CACHE_LOCK; 124 /* 125 * Allow unmatched Stream IDs to allocate bypass 126 * TLB entries for reduced latency. 127 */ 128 reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN; 129 arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg); 130 131 /* 132 * Disable MMU-500's not-particularly-beneficial next-page 133 * prefetcher for the sake of at least 5 known errata. 134 */ 135 for (i = 0; i < smmu->num_context_banks; ++i) { 136 reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); 137 reg &= ~ARM_MMU500_ACTLR_CPRE; 138 arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg); 139 reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); 140 if (reg & ARM_MMU500_ACTLR_CPRE) 141 dev_warn_once(smmu->dev, "Failed to disable prefetcher for errata workarounds, check SACR.CACHE_LOCK\n"); 142 } 143 144 return 0; 145 } 146 147 static const struct arm_smmu_impl arm_mmu500_impl = { 148 .reset = arm_mmu500_reset, 149 }; 150 151 static u64 mrvl_mmu500_readq(struct arm_smmu_device *smmu, int page, int off) 152 { 153 /* 154 * Marvell Armada-AP806 erratum #582743. 155 * Split all the readq to double readl 156 */ 157 return hi_lo_readq_relaxed(arm_smmu_page(smmu, page) + off); 158 } 159 160 static void mrvl_mmu500_writeq(struct arm_smmu_device *smmu, int page, int off, 161 u64 val) 162 { 163 /* 164 * Marvell Armada-AP806 erratum #582743. 165 * Split all the writeq to double writel 166 */ 167 hi_lo_writeq_relaxed(val, arm_smmu_page(smmu, page) + off); 168 } 169 170 static int mrvl_mmu500_cfg_probe(struct arm_smmu_device *smmu) 171 { 172 173 /* 174 * Armada-AP806 erratum #582743. 175 * Hide the SMMU_IDR2.PTFSv8 fields to sidestep the AArch64 176 * formats altogether and allow using 32 bits access on the 177 * interconnect. 178 */ 179 smmu->features &= ~(ARM_SMMU_FEAT_FMT_AARCH64_4K | 180 ARM_SMMU_FEAT_FMT_AARCH64_16K | 181 ARM_SMMU_FEAT_FMT_AARCH64_64K); 182 183 return 0; 184 } 185 186 static const struct arm_smmu_impl mrvl_mmu500_impl = { 187 .read_reg64 = mrvl_mmu500_readq, 188 .write_reg64 = mrvl_mmu500_writeq, 189 .cfg_probe = mrvl_mmu500_cfg_probe, 190 .reset = arm_mmu500_reset, 191 }; 192 193 194 struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) 195 { 196 const struct device_node *np = smmu->dev->of_node; 197 198 /* 199 * Set the impl for model-specific implementation quirks first, 200 * such that platform integration quirks can pick it up and 201 * inherit from it if necessary. 202 */ 203 switch (smmu->model) { 204 case ARM_MMU500: 205 smmu->impl = &arm_mmu500_impl; 206 break; 207 case CAVIUM_SMMUV2: 208 return cavium_smmu_impl_init(smmu); 209 default: 210 break; 211 } 212 213 /* This is implicitly MMU-400 */ 214 if (of_property_read_bool(np, "calxeda,smmu-secure-config-access")) 215 smmu->impl = &calxeda_impl; 216 217 if (of_device_is_compatible(np, "nvidia,tegra234-smmu") || 218 of_device_is_compatible(np, "nvidia,tegra194-smmu") || 219 of_device_is_compatible(np, "nvidia,tegra186-smmu")) 220 return nvidia_smmu_impl_init(smmu); 221 222 if (IS_ENABLED(CONFIG_ARM_SMMU_QCOM)) 223 smmu = qcom_smmu_impl_init(smmu); 224 225 if (of_device_is_compatible(np, "marvell,ap806-smmu-500")) 226 smmu->impl = &mrvl_mmu500_impl; 227 228 return smmu; 229 } 230