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 errata #841119 and #826419.
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 	}
140 
141 	return 0;
142 }
143 
144 static const struct arm_smmu_impl arm_mmu500_impl = {
145 	.reset = arm_mmu500_reset,
146 };
147 
148 static u64 mrvl_mmu500_readq(struct arm_smmu_device *smmu, int page, int off)
149 {
150 	/*
151 	 * Marvell Armada-AP806 erratum #582743.
152 	 * Split all the readq to double readl
153 	 */
154 	return hi_lo_readq_relaxed(arm_smmu_page(smmu, page) + off);
155 }
156 
157 static void mrvl_mmu500_writeq(struct arm_smmu_device *smmu, int page, int off,
158 			       u64 val)
159 {
160 	/*
161 	 * Marvell Armada-AP806 erratum #582743.
162 	 * Split all the writeq to double writel
163 	 */
164 	hi_lo_writeq_relaxed(val, arm_smmu_page(smmu, page) + off);
165 }
166 
167 static int mrvl_mmu500_cfg_probe(struct arm_smmu_device *smmu)
168 {
169 
170 	/*
171 	 * Armada-AP806 erratum #582743.
172 	 * Hide the SMMU_IDR2.PTFSv8 fields to sidestep the AArch64
173 	 * formats altogether and allow using 32 bits access on the
174 	 * interconnect.
175 	 */
176 	smmu->features &= ~(ARM_SMMU_FEAT_FMT_AARCH64_4K |
177 			    ARM_SMMU_FEAT_FMT_AARCH64_16K |
178 			    ARM_SMMU_FEAT_FMT_AARCH64_64K);
179 
180 	return 0;
181 }
182 
183 static const struct arm_smmu_impl mrvl_mmu500_impl = {
184 	.read_reg64 = mrvl_mmu500_readq,
185 	.write_reg64 = mrvl_mmu500_writeq,
186 	.cfg_probe = mrvl_mmu500_cfg_probe,
187 	.reset = arm_mmu500_reset,
188 };
189 
190 
191 struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu)
192 {
193 	const struct device_node *np = smmu->dev->of_node;
194 
195 	/*
196 	 * Set the impl for model-specific implementation quirks first,
197 	 * such that platform integration quirks can pick it up and
198 	 * inherit from it if necessary.
199 	 */
200 	switch (smmu->model) {
201 	case ARM_MMU500:
202 		smmu->impl = &arm_mmu500_impl;
203 		break;
204 	case CAVIUM_SMMUV2:
205 		return cavium_smmu_impl_init(smmu);
206 	default:
207 		break;
208 	}
209 
210 	/* This is implicitly MMU-400 */
211 	if (of_property_read_bool(np, "calxeda,smmu-secure-config-access"))
212 		smmu->impl = &calxeda_impl;
213 
214 	if (of_device_is_compatible(np, "nvidia,tegra194-smmu"))
215 		return nvidia_smmu_impl_init(smmu);
216 
217 	smmu = qcom_smmu_impl_init(smmu);
218 
219 	if (of_device_is_compatible(np, "marvell,ap806-smmu-500"))
220 		smmu->impl = &mrvl_mmu500_impl;
221 
222 	return smmu;
223 }
224