xref: /linux/arch/arm64/kernel/cpufeature.c (revision c5d3cdad688ed75fb311a3a671eb30ba7106d7d3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Contains CPU feature definitions
4  *
5  * Copyright (C) 2015 ARM Ltd.
6  */
7 
8 #define pr_fmt(fmt) "CPU features: " fmt
9 
10 #include <linux/bsearch.h>
11 #include <linux/cpumask.h>
12 #include <linux/crash_dump.h>
13 #include <linux/sort.h>
14 #include <linux/stop_machine.h>
15 #include <linux/types.h>
16 #include <linux/mm.h>
17 #include <linux/cpu.h>
18 #include <asm/cpu.h>
19 #include <asm/cpufeature.h>
20 #include <asm/cpu_ops.h>
21 #include <asm/fpsimd.h>
22 #include <asm/mmu_context.h>
23 #include <asm/processor.h>
24 #include <asm/sysreg.h>
25 #include <asm/traps.h>
26 #include <asm/virt.h>
27 
28 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
29 static unsigned long elf_hwcap __read_mostly;
30 
31 #ifdef CONFIG_COMPAT
32 #define COMPAT_ELF_HWCAP_DEFAULT	\
33 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
34 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
35 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
36 				 COMPAT_HWCAP_LPAE)
37 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
38 unsigned int compat_elf_hwcap2 __read_mostly;
39 #endif
40 
41 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
42 EXPORT_SYMBOL(cpu_hwcaps);
43 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
44 
45 /* Need also bit for ARM64_CB_PATCH */
46 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
47 
48 bool arm64_use_ng_mappings = false;
49 EXPORT_SYMBOL(arm64_use_ng_mappings);
50 
51 /*
52  * Flag to indicate if we have computed the system wide
53  * capabilities based on the boot time active CPUs. This
54  * will be used to determine if a new booting CPU should
55  * go through the verification process to make sure that it
56  * supports the system capabilities, without using a hotplug
57  * notifier. This is also used to decide if we could use
58  * the fast path for checking constant CPU caps.
59  */
60 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
61 EXPORT_SYMBOL(arm64_const_caps_ready);
62 static inline void finalize_system_capabilities(void)
63 {
64 	static_branch_enable(&arm64_const_caps_ready);
65 }
66 
67 static int dump_cpu_hwcaps(struct notifier_block *self, unsigned long v, void *p)
68 {
69 	/* file-wide pr_fmt adds "CPU features: " prefix */
70 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
71 	return 0;
72 }
73 
74 static struct notifier_block cpu_hwcaps_notifier = {
75 	.notifier_call = dump_cpu_hwcaps
76 };
77 
78 static int __init register_cpu_hwcaps_dumper(void)
79 {
80 	atomic_notifier_chain_register(&panic_notifier_list,
81 				       &cpu_hwcaps_notifier);
82 	return 0;
83 }
84 __initcall(register_cpu_hwcaps_dumper);
85 
86 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
87 EXPORT_SYMBOL(cpu_hwcap_keys);
88 
89 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
90 	{						\
91 		.sign = SIGNED,				\
92 		.visible = VISIBLE,			\
93 		.strict = STRICT,			\
94 		.type = TYPE,				\
95 		.shift = SHIFT,				\
96 		.width = WIDTH,				\
97 		.safe_val = SAFE_VAL,			\
98 	}
99 
100 /* Define a feature with unsigned values */
101 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
102 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
103 
104 /* Define a feature with a signed value */
105 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
106 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
107 
108 #define ARM64_FTR_END					\
109 	{						\
110 		.width = 0,				\
111 	}
112 
113 /* meta feature for alternatives */
114 static bool __maybe_unused
115 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
116 
117 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
118 
119 static bool __system_matches_cap(unsigned int n);
120 
121 /*
122  * NOTE: Any changes to the visibility of features should be kept in
123  * sync with the documentation of the CPU feature register ABI.
124  */
125 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
126 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
127 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
128 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
129 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
130 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
131 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
132 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
133 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
134 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
135 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
136 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
137 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
138 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
139 	ARM64_FTR_END,
140 };
141 
142 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
143 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
144 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
145 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
146 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
147 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
148 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
149 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
150 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
151 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
152 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
153 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
154 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
155 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
156 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
157 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_API_SHIFT, 4, 0),
158 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
159 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_APA_SHIFT, 4, 0),
160 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
161 	ARM64_FTR_END,
162 };
163 
164 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
165 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
166 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
167 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
168 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
169 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
170 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
171 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
172 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
173 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
174 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
175 	/* Linux doesn't care about the EL3 */
176 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
178 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
179 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
180 	ARM64_FTR_END,
181 };
182 
183 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
184 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
185 	ARM64_FTR_END,
186 };
187 
188 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
189 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
190 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
192 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
194 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
196 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
198 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
200 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
202 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
204 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
206 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
207 	ARM64_FTR_END,
208 };
209 
210 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
211 	/*
212 	 * We already refuse to boot CPUs that don't support our configured
213 	 * page size, so we can only detect mismatches for a page size other
214 	 * than the one we're currently using. Unfortunately, SoCs like this
215 	 * exist in the wild so, even though we don't like it, we'll have to go
216 	 * along with it and treat them as non-strict.
217 	 */
218 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
219 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
220 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
221 
222 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
223 	/* Linux shouldn't care about secure memory */
224 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
227 	/*
228 	 * Differing PARange is fine as long as all peripherals and memory are mapped
229 	 * within the minimum PARange of all CPUs
230 	 */
231 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
232 	ARM64_FTR_END,
233 };
234 
235 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
236 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
238 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
239 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
242 	ARM64_FTR_END,
243 };
244 
245 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
246 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
247 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
251 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
252 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
253 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
254 	ARM64_FTR_END,
255 };
256 
257 static const struct arm64_ftr_bits ftr_ctr[] = {
258 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
259 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
260 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
261 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
263 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
264 	/*
265 	 * Linux can handle differing I-cache policies. Userspace JITs will
266 	 * make use of *minLine.
267 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
268 	 */
269 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
270 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
271 	ARM64_FTR_END,
272 };
273 
274 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
275 	.name		= "SYS_CTR_EL0",
276 	.ftr_bits	= ftr_ctr
277 };
278 
279 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
280 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0xf),	/* InnerShr */
281 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),	/* FCSE */
282 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* AuxReg */
283 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),	/* TCM */
284 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),	/* ShareLvl */
285 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0xf),	/* OuterShr */
286 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),	/* PMSA */
287 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* VMSA */
288 	ARM64_FTR_END,
289 };
290 
291 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
292 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 36, 28, 0),
293 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
294 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
295 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
296 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
297 	/*
298 	 * We can instantiate multiple PMU instances with different levels
299 	 * of support.
300 	 */
301 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
302 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
303 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
304 	ARM64_FTR_END,
305 };
306 
307 static const struct arm64_ftr_bits ftr_mvfr2[] = {
308 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),		/* FPMisc */
309 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),		/* SIMDMisc */
310 	ARM64_FTR_END,
311 };
312 
313 static const struct arm64_ftr_bits ftr_dczid[] = {
314 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 4, 1, 1),		/* DZP */
315 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* BS */
316 	ARM64_FTR_END,
317 };
318 
319 
320 static const struct arm64_ftr_bits ftr_id_isar5[] = {
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
324 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
326 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
327 	ARM64_FTR_END,
328 };
329 
330 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
331 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),	/* ac2 */
332 	ARM64_FTR_END,
333 };
334 
335 static const struct arm64_ftr_bits ftr_id_isar6[] = {
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
343 	ARM64_FTR_END,
344 };
345 
346 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
347 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),		/* State3 */
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),		/* State2 */
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),		/* State1 */
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),		/* State0 */
351 	ARM64_FTR_END,
352 };
353 
354 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
356 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf),	/* PerfMon */
357 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
358 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
360 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
361 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
362 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
363 	ARM64_FTR_END,
364 };
365 
366 static const struct arm64_ftr_bits ftr_zcr[] = {
367 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
368 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
369 	ARM64_FTR_END,
370 };
371 
372 /*
373  * Common ftr bits for a 32bit register with all hidden, strict
374  * attributes, with 4bit feature fields and a default safe value of
375  * 0. Covers the following 32bit registers:
376  * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
377  */
378 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
379 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
380 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
381 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
382 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
383 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
384 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
385 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
387 	ARM64_FTR_END,
388 };
389 
390 /* Table for a single 32bit feature value */
391 static const struct arm64_ftr_bits ftr_single32[] = {
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
393 	ARM64_FTR_END,
394 };
395 
396 static const struct arm64_ftr_bits ftr_raz[] = {
397 	ARM64_FTR_END,
398 };
399 
400 #define ARM64_FTR_REG(id, table) {		\
401 	.sys_id = id,				\
402 	.reg = 	&(struct arm64_ftr_reg){	\
403 		.name = #id,			\
404 		.ftr_bits = &((table)[0]),	\
405 	}}
406 
407 static const struct __ftr_reg_entry {
408 	u32			sys_id;
409 	struct arm64_ftr_reg 	*reg;
410 } arm64_ftr_regs[] = {
411 
412 	/* Op1 = 0, CRn = 0, CRm = 1 */
413 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
414 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
415 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
416 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
417 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
418 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
419 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
420 
421 	/* Op1 = 0, CRn = 0, CRm = 2 */
422 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
423 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
424 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
425 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
426 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
427 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
428 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
429 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
430 
431 	/* Op1 = 0, CRn = 0, CRm = 3 */
432 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
433 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
434 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
435 
436 	/* Op1 = 0, CRn = 0, CRm = 4 */
437 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
438 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
439 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
440 
441 	/* Op1 = 0, CRn = 0, CRm = 5 */
442 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
443 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
444 
445 	/* Op1 = 0, CRn = 0, CRm = 6 */
446 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
447 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
448 
449 	/* Op1 = 0, CRn = 0, CRm = 7 */
450 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
451 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
452 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
453 
454 	/* Op1 = 0, CRn = 1, CRm = 2 */
455 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
456 
457 	/* Op1 = 3, CRn = 0, CRm = 0 */
458 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
459 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
460 
461 	/* Op1 = 3, CRn = 14, CRm = 0 */
462 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
463 };
464 
465 static int search_cmp_ftr_reg(const void *id, const void *regp)
466 {
467 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
468 }
469 
470 /*
471  * get_arm64_ftr_reg - Lookup a feature register entry using its
472  * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
473  * ascending order of sys_id , we use binary search to find a matching
474  * entry.
475  *
476  * returns - Upon success,  matching ftr_reg entry for id.
477  *         - NULL on failure. It is upto the caller to decide
478  *	     the impact of a failure.
479  */
480 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
481 {
482 	const struct __ftr_reg_entry *ret;
483 
484 	ret = bsearch((const void *)(unsigned long)sys_id,
485 			arm64_ftr_regs,
486 			ARRAY_SIZE(arm64_ftr_regs),
487 			sizeof(arm64_ftr_regs[0]),
488 			search_cmp_ftr_reg);
489 	if (ret)
490 		return ret->reg;
491 	return NULL;
492 }
493 
494 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
495 			       s64 ftr_val)
496 {
497 	u64 mask = arm64_ftr_mask(ftrp);
498 
499 	reg &= ~mask;
500 	reg |= (ftr_val << ftrp->shift) & mask;
501 	return reg;
502 }
503 
504 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
505 				s64 cur)
506 {
507 	s64 ret = 0;
508 
509 	switch (ftrp->type) {
510 	case FTR_EXACT:
511 		ret = ftrp->safe_val;
512 		break;
513 	case FTR_LOWER_SAFE:
514 		ret = new < cur ? new : cur;
515 		break;
516 	case FTR_HIGHER_OR_ZERO_SAFE:
517 		if (!cur || !new)
518 			break;
519 		/* Fallthrough */
520 	case FTR_HIGHER_SAFE:
521 		ret = new > cur ? new : cur;
522 		break;
523 	default:
524 		BUG();
525 	}
526 
527 	return ret;
528 }
529 
530 static void __init sort_ftr_regs(void)
531 {
532 	int i;
533 
534 	/* Check that the array is sorted so that we can do the binary search */
535 	for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++)
536 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
537 }
538 
539 /*
540  * Initialise the CPU feature register from Boot CPU values.
541  * Also initiliases the strict_mask for the register.
542  * Any bits that are not covered by an arm64_ftr_bits entry are considered
543  * RES0 for the system-wide value, and must strictly match.
544  */
545 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
546 {
547 	u64 val = 0;
548 	u64 strict_mask = ~0x0ULL;
549 	u64 user_mask = 0;
550 	u64 valid_mask = 0;
551 
552 	const struct arm64_ftr_bits *ftrp;
553 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
554 
555 	BUG_ON(!reg);
556 
557 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
558 		u64 ftr_mask = arm64_ftr_mask(ftrp);
559 		s64 ftr_new = arm64_ftr_value(ftrp, new);
560 
561 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
562 
563 		valid_mask |= ftr_mask;
564 		if (!ftrp->strict)
565 			strict_mask &= ~ftr_mask;
566 		if (ftrp->visible)
567 			user_mask |= ftr_mask;
568 		else
569 			reg->user_val = arm64_ftr_set_value(ftrp,
570 							    reg->user_val,
571 							    ftrp->safe_val);
572 	}
573 
574 	val &= valid_mask;
575 
576 	reg->sys_val = val;
577 	reg->strict_mask = strict_mask;
578 	reg->user_mask = user_mask;
579 }
580 
581 extern const struct arm64_cpu_capabilities arm64_errata[];
582 static const struct arm64_cpu_capabilities arm64_features[];
583 
584 static void __init
585 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
586 {
587 	for (; caps->matches; caps++) {
588 		if (WARN(caps->capability >= ARM64_NCAPS,
589 			"Invalid capability %d\n", caps->capability))
590 			continue;
591 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
592 			"Duplicate entry for capability %d\n",
593 			caps->capability))
594 			continue;
595 		cpu_hwcaps_ptrs[caps->capability] = caps;
596 	}
597 }
598 
599 static void __init init_cpu_hwcaps_indirect_list(void)
600 {
601 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
602 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
603 }
604 
605 static void __init setup_boot_cpu_capabilities(void);
606 
607 void __init init_cpu_features(struct cpuinfo_arm64 *info)
608 {
609 	/* Before we start using the tables, make sure it is sorted */
610 	sort_ftr_regs();
611 
612 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
613 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
614 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
615 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
616 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
617 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
618 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
619 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
620 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
621 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
622 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
623 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
624 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
625 
626 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
627 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
628 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
629 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
630 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
631 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
632 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
633 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
634 		init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
635 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
636 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
637 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
638 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
639 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
640 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
641 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
642 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
643 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
644 	}
645 
646 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
647 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
648 		sve_init_vq_map();
649 	}
650 
651 	/*
652 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
653 	 * before we handle the boot CPU below.
654 	 */
655 	init_cpu_hwcaps_indirect_list();
656 
657 	/*
658 	 * Detect and enable early CPU capabilities based on the boot CPU,
659 	 * after we have initialised the CPU feature infrastructure.
660 	 */
661 	setup_boot_cpu_capabilities();
662 }
663 
664 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
665 {
666 	const struct arm64_ftr_bits *ftrp;
667 
668 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
669 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
670 		s64 ftr_new = arm64_ftr_value(ftrp, new);
671 
672 		if (ftr_cur == ftr_new)
673 			continue;
674 		/* Find a safe value */
675 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
676 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
677 	}
678 
679 }
680 
681 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
682 {
683 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
684 
685 	BUG_ON(!regp);
686 	update_cpu_ftr_reg(regp, val);
687 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
688 		return 0;
689 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
690 			regp->name, boot, cpu, val);
691 	return 1;
692 }
693 
694 /*
695  * Update system wide CPU feature registers with the values from a
696  * non-boot CPU. Also performs SANITY checks to make sure that there
697  * aren't any insane variations from that of the boot CPU.
698  */
699 void update_cpu_features(int cpu,
700 			 struct cpuinfo_arm64 *info,
701 			 struct cpuinfo_arm64 *boot)
702 {
703 	int taint = 0;
704 
705 	/*
706 	 * The kernel can handle differing I-cache policies, but otherwise
707 	 * caches should look identical. Userspace JITs will make use of
708 	 * *minLine.
709 	 */
710 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
711 				      info->reg_ctr, boot->reg_ctr);
712 
713 	/*
714 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
715 	 * could result in too much or too little memory being zeroed if a
716 	 * process is preempted and migrated between CPUs.
717 	 */
718 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
719 				      info->reg_dczid, boot->reg_dczid);
720 
721 	/* If different, timekeeping will be broken (especially with KVM) */
722 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
723 				      info->reg_cntfrq, boot->reg_cntfrq);
724 
725 	/*
726 	 * The kernel uses self-hosted debug features and expects CPUs to
727 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
728 	 * and BRPs to be identical.
729 	 * ID_AA64DFR1 is currently RES0.
730 	 */
731 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
732 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
733 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
734 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
735 	/*
736 	 * Even in big.LITTLE, processors should be identical instruction-set
737 	 * wise.
738 	 */
739 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
740 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
741 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
742 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
743 
744 	/*
745 	 * Differing PARange support is fine as long as all peripherals and
746 	 * memory are mapped within the minimum PARange of all CPUs.
747 	 * Linux should not care about secure memory.
748 	 */
749 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
750 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
751 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
752 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
753 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
754 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
755 
756 	/*
757 	 * EL3 is not our concern.
758 	 */
759 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
760 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
761 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
762 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
763 
764 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
765 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
766 
767 	/*
768 	 * If we have AArch32, we care about 32-bit features for compat.
769 	 * If the system doesn't support AArch32, don't update them.
770 	 */
771 	if (id_aa64pfr0_32bit_el0(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
772 		id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
773 
774 		taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
775 					info->reg_id_dfr0, boot->reg_id_dfr0);
776 		taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
777 					info->reg_id_isar0, boot->reg_id_isar0);
778 		taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
779 					info->reg_id_isar1, boot->reg_id_isar1);
780 		taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
781 					info->reg_id_isar2, boot->reg_id_isar2);
782 		taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
783 					info->reg_id_isar3, boot->reg_id_isar3);
784 		taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
785 					info->reg_id_isar4, boot->reg_id_isar4);
786 		taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
787 					info->reg_id_isar5, boot->reg_id_isar5);
788 		taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
789 					info->reg_id_isar6, boot->reg_id_isar6);
790 
791 		/*
792 		 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
793 		 * ACTLR formats could differ across CPUs and therefore would have to
794 		 * be trapped for virtualization anyway.
795 		 */
796 		taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
797 					info->reg_id_mmfr0, boot->reg_id_mmfr0);
798 		taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
799 					info->reg_id_mmfr1, boot->reg_id_mmfr1);
800 		taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
801 					info->reg_id_mmfr2, boot->reg_id_mmfr2);
802 		taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
803 					info->reg_id_mmfr3, boot->reg_id_mmfr3);
804 		taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
805 					info->reg_id_pfr0, boot->reg_id_pfr0);
806 		taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
807 					info->reg_id_pfr1, boot->reg_id_pfr1);
808 		taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
809 					info->reg_mvfr0, boot->reg_mvfr0);
810 		taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
811 					info->reg_mvfr1, boot->reg_mvfr1);
812 		taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
813 					info->reg_mvfr2, boot->reg_mvfr2);
814 	}
815 
816 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
817 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
818 					info->reg_zcr, boot->reg_zcr);
819 
820 		/* Probe vector lengths, unless we already gave up on SVE */
821 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
822 		    !system_capabilities_finalized())
823 			sve_update_vq_map();
824 	}
825 
826 	/*
827 	 * Mismatched CPU features are a recipe for disaster. Don't even
828 	 * pretend to support them.
829 	 */
830 	if (taint) {
831 		pr_warn_once("Unsupported CPU feature variation detected.\n");
832 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
833 	}
834 }
835 
836 u64 read_sanitised_ftr_reg(u32 id)
837 {
838 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
839 
840 	/* We shouldn't get a request for an unsupported register */
841 	BUG_ON(!regp);
842 	return regp->sys_val;
843 }
844 
845 #define read_sysreg_case(r)	\
846 	case r:		return read_sysreg_s(r)
847 
848 /*
849  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
850  * Read the system register on the current CPU
851  */
852 static u64 __read_sysreg_by_encoding(u32 sys_id)
853 {
854 	switch (sys_id) {
855 	read_sysreg_case(SYS_ID_PFR0_EL1);
856 	read_sysreg_case(SYS_ID_PFR1_EL1);
857 	read_sysreg_case(SYS_ID_DFR0_EL1);
858 	read_sysreg_case(SYS_ID_MMFR0_EL1);
859 	read_sysreg_case(SYS_ID_MMFR1_EL1);
860 	read_sysreg_case(SYS_ID_MMFR2_EL1);
861 	read_sysreg_case(SYS_ID_MMFR3_EL1);
862 	read_sysreg_case(SYS_ID_ISAR0_EL1);
863 	read_sysreg_case(SYS_ID_ISAR1_EL1);
864 	read_sysreg_case(SYS_ID_ISAR2_EL1);
865 	read_sysreg_case(SYS_ID_ISAR3_EL1);
866 	read_sysreg_case(SYS_ID_ISAR4_EL1);
867 	read_sysreg_case(SYS_ID_ISAR5_EL1);
868 	read_sysreg_case(SYS_ID_ISAR6_EL1);
869 	read_sysreg_case(SYS_MVFR0_EL1);
870 	read_sysreg_case(SYS_MVFR1_EL1);
871 	read_sysreg_case(SYS_MVFR2_EL1);
872 
873 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
874 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
875 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
876 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
877 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
878 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
879 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
880 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
881 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
882 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
883 
884 	read_sysreg_case(SYS_CNTFRQ_EL0);
885 	read_sysreg_case(SYS_CTR_EL0);
886 	read_sysreg_case(SYS_DCZID_EL0);
887 
888 	default:
889 		BUG();
890 		return 0;
891 	}
892 }
893 
894 #include <linux/irqchip/arm-gic-v3.h>
895 
896 static bool
897 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
898 {
899 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
900 
901 	return val >= entry->min_field_value;
902 }
903 
904 static bool
905 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
906 {
907 	u64 val;
908 
909 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
910 	if (scope == SCOPE_SYSTEM)
911 		val = read_sanitised_ftr_reg(entry->sys_reg);
912 	else
913 		val = __read_sysreg_by_encoding(entry->sys_reg);
914 
915 	return feature_matches(val, entry);
916 }
917 
918 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
919 {
920 	bool has_sre;
921 
922 	if (!has_cpuid_feature(entry, scope))
923 		return false;
924 
925 	has_sre = gic_enable_sre();
926 	if (!has_sre)
927 		pr_warn_once("%s present but disabled by higher exception level\n",
928 			     entry->desc);
929 
930 	return has_sre;
931 }
932 
933 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
934 {
935 	u32 midr = read_cpuid_id();
936 
937 	/* Cavium ThunderX pass 1.x and 2.x */
938 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
939 		MIDR_CPU_VAR_REV(0, 0),
940 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
941 }
942 
943 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
944 {
945 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
946 
947 	return cpuid_feature_extract_signed_field(pfr0,
948 					ID_AA64PFR0_FP_SHIFT) < 0;
949 }
950 
951 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
952 			  int scope)
953 {
954 	u64 ctr;
955 
956 	if (scope == SCOPE_SYSTEM)
957 		ctr = arm64_ftr_reg_ctrel0.sys_val;
958 	else
959 		ctr = read_cpuid_effective_cachetype();
960 
961 	return ctr & BIT(CTR_IDC_SHIFT);
962 }
963 
964 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
965 {
966 	/*
967 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
968 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
969 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
970 	 * value.
971 	 */
972 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
973 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
974 }
975 
976 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
977 			  int scope)
978 {
979 	u64 ctr;
980 
981 	if (scope == SCOPE_SYSTEM)
982 		ctr = arm64_ftr_reg_ctrel0.sys_val;
983 	else
984 		ctr = read_cpuid_cachetype();
985 
986 	return ctr & BIT(CTR_DIC_SHIFT);
987 }
988 
989 static bool __maybe_unused
990 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
991 {
992 	/*
993 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
994 	 * may share TLB entries with a CPU stuck in the crashed
995 	 * kernel.
996 	 */
997 	 if (is_kdump_kernel())
998 		return false;
999 
1000 	return has_cpuid_feature(entry, scope);
1001 }
1002 
1003 /*
1004  * This check is triggered during the early boot before the cpufeature
1005  * is initialised. Checking the status on the local CPU allows the boot
1006  * CPU to detect the need for non-global mappings and thus avoiding a
1007  * pagetable re-write after all the CPUs are booted. This check will be
1008  * anyway run on individual CPUs, allowing us to get the consistent
1009  * state once the SMP CPUs are up and thus make the switch to non-global
1010  * mappings if required.
1011  */
1012 bool kaslr_requires_kpti(void)
1013 {
1014 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1015 		return false;
1016 
1017 	/*
1018 	 * E0PD does a similar job to KPTI so can be used instead
1019 	 * where available.
1020 	 */
1021 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1022 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1023 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1024 						ID_AA64MMFR2_E0PD_SHIFT))
1025 			return false;
1026 	}
1027 
1028 	/*
1029 	 * Systems affected by Cavium erratum 24756 are incompatible
1030 	 * with KPTI.
1031 	 */
1032 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1033 		extern const struct midr_range cavium_erratum_27456_cpus[];
1034 
1035 		if (is_midr_in_range_list(read_cpuid_id(),
1036 					  cavium_erratum_27456_cpus))
1037 			return false;
1038 	}
1039 
1040 	return kaslr_offset() > 0;
1041 }
1042 
1043 static bool __meltdown_safe = true;
1044 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1045 
1046 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1047 				int scope)
1048 {
1049 	/* List of CPUs that are not vulnerable and don't need KPTI */
1050 	static const struct midr_range kpti_safe_list[] = {
1051 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1052 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1053 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1054 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1055 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1056 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1057 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1058 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1059 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1060 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1061 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1062 		{ /* sentinel */ }
1063 	};
1064 	char const *str = "kpti command line option";
1065 	bool meltdown_safe;
1066 
1067 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1068 
1069 	/* Defer to CPU feature registers */
1070 	if (has_cpuid_feature(entry, scope))
1071 		meltdown_safe = true;
1072 
1073 	if (!meltdown_safe)
1074 		__meltdown_safe = false;
1075 
1076 	/*
1077 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1078 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1079 	 * ends as well as you might imagine. Don't even try.
1080 	 */
1081 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1082 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1083 		__kpti_forced = -1;
1084 	}
1085 
1086 	/* Useful for KASLR robustness */
1087 	if (kaslr_requires_kpti()) {
1088 		if (!__kpti_forced) {
1089 			str = "KASLR";
1090 			__kpti_forced = 1;
1091 		}
1092 	}
1093 
1094 	if (cpu_mitigations_off() && !__kpti_forced) {
1095 		str = "mitigations=off";
1096 		__kpti_forced = -1;
1097 	}
1098 
1099 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1100 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1101 		return false;
1102 	}
1103 
1104 	/* Forced? */
1105 	if (__kpti_forced) {
1106 		pr_info_once("kernel page table isolation forced %s by %s\n",
1107 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1108 		return __kpti_forced > 0;
1109 	}
1110 
1111 	return !meltdown_safe;
1112 }
1113 
1114 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1115 static void
1116 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1117 {
1118 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1119 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1120 	kpti_remap_fn *remap_fn;
1121 
1122 	int cpu = smp_processor_id();
1123 
1124 	/*
1125 	 * We don't need to rewrite the page-tables if either we've done
1126 	 * it already or we have KASLR enabled and therefore have not
1127 	 * created any global mappings at all.
1128 	 */
1129 	if (arm64_use_ng_mappings)
1130 		return;
1131 
1132 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1133 
1134 	cpu_install_idmap();
1135 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1136 	cpu_uninstall_idmap();
1137 
1138 	if (!cpu)
1139 		arm64_use_ng_mappings = true;
1140 
1141 	return;
1142 }
1143 #else
1144 static void
1145 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1146 {
1147 }
1148 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1149 
1150 static int __init parse_kpti(char *str)
1151 {
1152 	bool enabled;
1153 	int ret = strtobool(str, &enabled);
1154 
1155 	if (ret)
1156 		return ret;
1157 
1158 	__kpti_forced = enabled ? 1 : -1;
1159 	return 0;
1160 }
1161 early_param("kpti", parse_kpti);
1162 
1163 #ifdef CONFIG_ARM64_HW_AFDBM
1164 static inline void __cpu_enable_hw_dbm(void)
1165 {
1166 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1167 
1168 	write_sysreg(tcr, tcr_el1);
1169 	isb();
1170 }
1171 
1172 static bool cpu_has_broken_dbm(void)
1173 {
1174 	/* List of CPUs which have broken DBM support. */
1175 	static const struct midr_range cpus[] = {
1176 #ifdef CONFIG_ARM64_ERRATUM_1024718
1177 		MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0),  // A55 r0p0 -r1p0
1178 #endif
1179 		{},
1180 	};
1181 
1182 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1183 }
1184 
1185 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1186 {
1187 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1188 	       !cpu_has_broken_dbm();
1189 }
1190 
1191 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1192 {
1193 	if (cpu_can_use_dbm(cap))
1194 		__cpu_enable_hw_dbm();
1195 }
1196 
1197 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1198 		       int __unused)
1199 {
1200 	static bool detected = false;
1201 	/*
1202 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1203 	 * run a mix of CPUs with and without the feature. So, we
1204 	 * unconditionally enable the capability to allow any late CPU
1205 	 * to use the feature. We only enable the control bits on the
1206 	 * CPU, if it actually supports.
1207 	 *
1208 	 * We have to make sure we print the "feature" detection only
1209 	 * when at least one CPU actually uses it. So check if this CPU
1210 	 * can actually use it and print the message exactly once.
1211 	 *
1212 	 * This is safe as all CPUs (including secondary CPUs - due to the
1213 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1214 	 * goes through the "matches" check exactly once. Also if a CPU
1215 	 * matches the criteria, it is guaranteed that the CPU will turn
1216 	 * the DBM on, as the capability is unconditionally enabled.
1217 	 */
1218 	if (!detected && cpu_can_use_dbm(cap)) {
1219 		detected = true;
1220 		pr_info("detected: Hardware dirty bit management\n");
1221 	}
1222 
1223 	return true;
1224 }
1225 
1226 #endif
1227 
1228 #ifdef CONFIG_ARM64_AMU_EXTN
1229 
1230 /*
1231  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1232  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1233  * information regarding all the events that it supports. When a CPU bit is
1234  * set in the cpumask, the user of this feature can only rely on the presence
1235  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1236  * counters are enabled or access to these counters is enabled by code
1237  * executed at higher exception levels (firmware).
1238  */
1239 static struct cpumask amu_cpus __read_mostly;
1240 
1241 bool cpu_has_amu_feat(int cpu)
1242 {
1243 	return cpumask_test_cpu(cpu, &amu_cpus);
1244 }
1245 
1246 /* Initialize the use of AMU counters for frequency invariance */
1247 extern void init_cpu_freq_invariance_counters(void);
1248 
1249 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1250 {
1251 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1252 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1253 			smp_processor_id());
1254 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1255 		init_cpu_freq_invariance_counters();
1256 	}
1257 }
1258 
1259 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1260 		    int __unused)
1261 {
1262 	/*
1263 	 * The AMU extension is a non-conflicting feature: the kernel can
1264 	 * safely run a mix of CPUs with and without support for the
1265 	 * activity monitors extension. Therefore, unconditionally enable
1266 	 * the capability to allow any late CPU to use the feature.
1267 	 *
1268 	 * With this feature unconditionally enabled, the cpu_enable
1269 	 * function will be called for all CPUs that match the criteria,
1270 	 * including secondary and hotplugged, marking this feature as
1271 	 * present on that respective CPU. The enable function will also
1272 	 * print a detection message.
1273 	 */
1274 
1275 	return true;
1276 }
1277 #endif
1278 
1279 #ifdef CONFIG_ARM64_VHE
1280 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1281 {
1282 	return is_kernel_in_hyp_mode();
1283 }
1284 
1285 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1286 {
1287 	/*
1288 	 * Copy register values that aren't redirected by hardware.
1289 	 *
1290 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1291 	 * this value to tpidr_el2 before we patch the code. Once we've done
1292 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1293 	 * do anything here.
1294 	 */
1295 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1296 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1297 }
1298 #endif
1299 
1300 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1301 {
1302 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1303 
1304 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1305 	WARN_ON(val & (7 << 27 | 7 << 21));
1306 }
1307 
1308 #ifdef CONFIG_ARM64_SSBD
1309 static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr)
1310 {
1311 	if (user_mode(regs))
1312 		return 1;
1313 
1314 	if (instr & BIT(PSTATE_Imm_shift))
1315 		regs->pstate |= PSR_SSBS_BIT;
1316 	else
1317 		regs->pstate &= ~PSR_SSBS_BIT;
1318 
1319 	arm64_skip_faulting_instruction(regs, 4);
1320 	return 0;
1321 }
1322 
1323 static struct undef_hook ssbs_emulation_hook = {
1324 	.instr_mask	= ~(1U << PSTATE_Imm_shift),
1325 	.instr_val	= 0xd500401f | PSTATE_SSBS,
1326 	.fn		= ssbs_emulation_handler,
1327 };
1328 
1329 static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused)
1330 {
1331 	static bool undef_hook_registered = false;
1332 	static DEFINE_RAW_SPINLOCK(hook_lock);
1333 
1334 	raw_spin_lock(&hook_lock);
1335 	if (!undef_hook_registered) {
1336 		register_undef_hook(&ssbs_emulation_hook);
1337 		undef_hook_registered = true;
1338 	}
1339 	raw_spin_unlock(&hook_lock);
1340 
1341 	if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) {
1342 		sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS);
1343 		arm64_set_ssbd_mitigation(false);
1344 	} else {
1345 		arm64_set_ssbd_mitigation(true);
1346 	}
1347 }
1348 #endif /* CONFIG_ARM64_SSBD */
1349 
1350 #ifdef CONFIG_ARM64_PAN
1351 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1352 {
1353 	/*
1354 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1355 	 * is discarded once we return from the exception.
1356 	 */
1357 	WARN_ON_ONCE(in_interrupt());
1358 
1359 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1360 	asm(SET_PSTATE_PAN(1));
1361 }
1362 #endif /* CONFIG_ARM64_PAN */
1363 
1364 #ifdef CONFIG_ARM64_RAS_EXTN
1365 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1366 {
1367 	/* Firmware may have left a deferred SError in this register. */
1368 	write_sysreg_s(0, SYS_DISR_EL1);
1369 }
1370 #endif /* CONFIG_ARM64_RAS_EXTN */
1371 
1372 #ifdef CONFIG_ARM64_PTR_AUTH
1373 static bool has_address_auth(const struct arm64_cpu_capabilities *entry,
1374 			     int __unused)
1375 {
1376 	return __system_matches_cap(ARM64_HAS_ADDRESS_AUTH_ARCH) ||
1377 	       __system_matches_cap(ARM64_HAS_ADDRESS_AUTH_IMP_DEF);
1378 }
1379 
1380 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1381 			     int __unused)
1382 {
1383 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1384 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1385 }
1386 #endif /* CONFIG_ARM64_PTR_AUTH */
1387 
1388 #ifdef CONFIG_ARM64_E0PD
1389 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1390 {
1391 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1392 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1393 }
1394 #endif /* CONFIG_ARM64_E0PD */
1395 
1396 #ifdef CONFIG_ARM64_PSEUDO_NMI
1397 static bool enable_pseudo_nmi;
1398 
1399 static int __init early_enable_pseudo_nmi(char *p)
1400 {
1401 	return strtobool(p, &enable_pseudo_nmi);
1402 }
1403 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1404 
1405 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1406 				   int scope)
1407 {
1408 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1409 }
1410 #endif
1411 
1412 /* Internal helper functions to match cpu capability type */
1413 static bool
1414 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1415 {
1416 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1417 }
1418 
1419 static bool
1420 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1421 {
1422 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1423 }
1424 
1425 static bool
1426 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1427 {
1428 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1429 }
1430 
1431 static const struct arm64_cpu_capabilities arm64_features[] = {
1432 	{
1433 		.desc = "GIC system register CPU interface",
1434 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1435 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1436 		.matches = has_useable_gicv3_cpuif,
1437 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1438 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1439 		.sign = FTR_UNSIGNED,
1440 		.min_field_value = 1,
1441 	},
1442 #ifdef CONFIG_ARM64_PAN
1443 	{
1444 		.desc = "Privileged Access Never",
1445 		.capability = ARM64_HAS_PAN,
1446 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1447 		.matches = has_cpuid_feature,
1448 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1449 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1450 		.sign = FTR_UNSIGNED,
1451 		.min_field_value = 1,
1452 		.cpu_enable = cpu_enable_pan,
1453 	},
1454 #endif /* CONFIG_ARM64_PAN */
1455 #ifdef CONFIG_ARM64_LSE_ATOMICS
1456 	{
1457 		.desc = "LSE atomic instructions",
1458 		.capability = ARM64_HAS_LSE_ATOMICS,
1459 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1460 		.matches = has_cpuid_feature,
1461 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1462 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1463 		.sign = FTR_UNSIGNED,
1464 		.min_field_value = 2,
1465 	},
1466 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1467 	{
1468 		.desc = "Software prefetching using PRFM",
1469 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1470 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1471 		.matches = has_no_hw_prefetch,
1472 	},
1473 #ifdef CONFIG_ARM64_UAO
1474 	{
1475 		.desc = "User Access Override",
1476 		.capability = ARM64_HAS_UAO,
1477 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1478 		.matches = has_cpuid_feature,
1479 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1480 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
1481 		.min_field_value = 1,
1482 		/*
1483 		 * We rely on stop_machine() calling uao_thread_switch() to set
1484 		 * UAO immediately after patching.
1485 		 */
1486 	},
1487 #endif /* CONFIG_ARM64_UAO */
1488 #ifdef CONFIG_ARM64_PAN
1489 	{
1490 		.capability = ARM64_ALT_PAN_NOT_UAO,
1491 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1492 		.matches = cpufeature_pan_not_uao,
1493 	},
1494 #endif /* CONFIG_ARM64_PAN */
1495 #ifdef CONFIG_ARM64_VHE
1496 	{
1497 		.desc = "Virtualization Host Extensions",
1498 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1499 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1500 		.matches = runs_at_el2,
1501 		.cpu_enable = cpu_copy_el2regs,
1502 	},
1503 #endif	/* CONFIG_ARM64_VHE */
1504 	{
1505 		.desc = "32-bit EL0 Support",
1506 		.capability = ARM64_HAS_32BIT_EL0,
1507 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1508 		.matches = has_cpuid_feature,
1509 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1510 		.sign = FTR_UNSIGNED,
1511 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1512 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1513 	},
1514 	{
1515 		.desc = "Kernel page table isolation (KPTI)",
1516 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1517 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1518 		/*
1519 		 * The ID feature fields below are used to indicate that
1520 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1521 		 * more details.
1522 		 */
1523 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1524 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1525 		.min_field_value = 1,
1526 		.matches = unmap_kernel_at_el0,
1527 		.cpu_enable = kpti_install_ng_mappings,
1528 	},
1529 	{
1530 		/* FP/SIMD is not implemented */
1531 		.capability = ARM64_HAS_NO_FPSIMD,
1532 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1533 		.min_field_value = 0,
1534 		.matches = has_no_fpsimd,
1535 	},
1536 #ifdef CONFIG_ARM64_PMEM
1537 	{
1538 		.desc = "Data cache clean to Point of Persistence",
1539 		.capability = ARM64_HAS_DCPOP,
1540 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1541 		.matches = has_cpuid_feature,
1542 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1543 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1544 		.min_field_value = 1,
1545 	},
1546 	{
1547 		.desc = "Data cache clean to Point of Deep Persistence",
1548 		.capability = ARM64_HAS_DCPODP,
1549 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1550 		.matches = has_cpuid_feature,
1551 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1552 		.sign = FTR_UNSIGNED,
1553 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1554 		.min_field_value = 2,
1555 	},
1556 #endif
1557 #ifdef CONFIG_ARM64_SVE
1558 	{
1559 		.desc = "Scalable Vector Extension",
1560 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1561 		.capability = ARM64_SVE,
1562 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1563 		.sign = FTR_UNSIGNED,
1564 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
1565 		.min_field_value = ID_AA64PFR0_SVE,
1566 		.matches = has_cpuid_feature,
1567 		.cpu_enable = sve_kernel_enable,
1568 	},
1569 #endif /* CONFIG_ARM64_SVE */
1570 #ifdef CONFIG_ARM64_RAS_EXTN
1571 	{
1572 		.desc = "RAS Extension Support",
1573 		.capability = ARM64_HAS_RAS_EXTN,
1574 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1575 		.matches = has_cpuid_feature,
1576 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1577 		.sign = FTR_UNSIGNED,
1578 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
1579 		.min_field_value = ID_AA64PFR0_RAS_V1,
1580 		.cpu_enable = cpu_clear_disr,
1581 	},
1582 #endif /* CONFIG_ARM64_RAS_EXTN */
1583 #ifdef CONFIG_ARM64_AMU_EXTN
1584 	{
1585 		/*
1586 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
1587 		 * Therefore, don't provide .desc as we don't want the detection
1588 		 * message to be shown until at least one CPU is detected to
1589 		 * support the feature.
1590 		 */
1591 		.capability = ARM64_HAS_AMU_EXTN,
1592 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1593 		.matches = has_amu,
1594 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1595 		.sign = FTR_UNSIGNED,
1596 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
1597 		.min_field_value = ID_AA64PFR0_AMU,
1598 		.cpu_enable = cpu_amu_enable,
1599 	},
1600 #endif /* CONFIG_ARM64_AMU_EXTN */
1601 	{
1602 		.desc = "Data cache clean to the PoU not required for I/D coherence",
1603 		.capability = ARM64_HAS_CACHE_IDC,
1604 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1605 		.matches = has_cache_idc,
1606 		.cpu_enable = cpu_emulate_effective_ctr,
1607 	},
1608 	{
1609 		.desc = "Instruction cache invalidation not required for I/D coherence",
1610 		.capability = ARM64_HAS_CACHE_DIC,
1611 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1612 		.matches = has_cache_dic,
1613 	},
1614 	{
1615 		.desc = "Stage-2 Force Write-Back",
1616 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1617 		.capability = ARM64_HAS_STAGE2_FWB,
1618 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1619 		.sign = FTR_UNSIGNED,
1620 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
1621 		.min_field_value = 1,
1622 		.matches = has_cpuid_feature,
1623 		.cpu_enable = cpu_has_fwb,
1624 	},
1625 #ifdef CONFIG_ARM64_HW_AFDBM
1626 	{
1627 		/*
1628 		 * Since we turn this on always, we don't want the user to
1629 		 * think that the feature is available when it may not be.
1630 		 * So hide the description.
1631 		 *
1632 		 * .desc = "Hardware pagetable Dirty Bit Management",
1633 		 *
1634 		 */
1635 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1636 		.capability = ARM64_HW_DBM,
1637 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1638 		.sign = FTR_UNSIGNED,
1639 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
1640 		.min_field_value = 2,
1641 		.matches = has_hw_dbm,
1642 		.cpu_enable = cpu_enable_hw_dbm,
1643 	},
1644 #endif
1645 	{
1646 		.desc = "CRC32 instructions",
1647 		.capability = ARM64_HAS_CRC32,
1648 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1649 		.matches = has_cpuid_feature,
1650 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1651 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
1652 		.min_field_value = 1,
1653 	},
1654 #ifdef CONFIG_ARM64_SSBD
1655 	{
1656 		.desc = "Speculative Store Bypassing Safe (SSBS)",
1657 		.capability = ARM64_SSBS,
1658 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1659 		.matches = has_cpuid_feature,
1660 		.sys_reg = SYS_ID_AA64PFR1_EL1,
1661 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
1662 		.sign = FTR_UNSIGNED,
1663 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
1664 		.cpu_enable = cpu_enable_ssbs,
1665 	},
1666 #endif
1667 #ifdef CONFIG_ARM64_CNP
1668 	{
1669 		.desc = "Common not Private translations",
1670 		.capability = ARM64_HAS_CNP,
1671 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1672 		.matches = has_useable_cnp,
1673 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1674 		.sign = FTR_UNSIGNED,
1675 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
1676 		.min_field_value = 1,
1677 		.cpu_enable = cpu_enable_cnp,
1678 	},
1679 #endif
1680 	{
1681 		.desc = "Speculation barrier (SB)",
1682 		.capability = ARM64_HAS_SB,
1683 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1684 		.matches = has_cpuid_feature,
1685 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1686 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
1687 		.sign = FTR_UNSIGNED,
1688 		.min_field_value = 1,
1689 	},
1690 #ifdef CONFIG_ARM64_PTR_AUTH
1691 	{
1692 		.desc = "Address authentication (architected algorithm)",
1693 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
1694 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
1695 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1696 		.sign = FTR_UNSIGNED,
1697 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
1698 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
1699 		.matches = has_cpuid_feature,
1700 	},
1701 	{
1702 		.desc = "Address authentication (IMP DEF algorithm)",
1703 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
1704 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
1705 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1706 		.sign = FTR_UNSIGNED,
1707 		.field_pos = ID_AA64ISAR1_API_SHIFT,
1708 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
1709 		.matches = has_cpuid_feature,
1710 	},
1711 	{
1712 		.capability = ARM64_HAS_ADDRESS_AUTH,
1713 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
1714 		.matches = has_address_auth,
1715 	},
1716 	{
1717 		.desc = "Generic authentication (architected algorithm)",
1718 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
1719 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1720 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1721 		.sign = FTR_UNSIGNED,
1722 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
1723 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
1724 		.matches = has_cpuid_feature,
1725 	},
1726 	{
1727 		.desc = "Generic authentication (IMP DEF algorithm)",
1728 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
1729 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1730 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1731 		.sign = FTR_UNSIGNED,
1732 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
1733 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
1734 		.matches = has_cpuid_feature,
1735 	},
1736 	{
1737 		.capability = ARM64_HAS_GENERIC_AUTH,
1738 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1739 		.matches = has_generic_auth,
1740 	},
1741 #endif /* CONFIG_ARM64_PTR_AUTH */
1742 #ifdef CONFIG_ARM64_PSEUDO_NMI
1743 	{
1744 		/*
1745 		 * Depends on having GICv3
1746 		 */
1747 		.desc = "IRQ priority masking",
1748 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
1749 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1750 		.matches = can_use_gic_priorities,
1751 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1752 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1753 		.sign = FTR_UNSIGNED,
1754 		.min_field_value = 1,
1755 	},
1756 #endif
1757 #ifdef CONFIG_ARM64_E0PD
1758 	{
1759 		.desc = "E0PD",
1760 		.capability = ARM64_HAS_E0PD,
1761 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1762 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1763 		.sign = FTR_UNSIGNED,
1764 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
1765 		.matches = has_cpuid_feature,
1766 		.min_field_value = 1,
1767 		.cpu_enable = cpu_enable_e0pd,
1768 	},
1769 #endif
1770 #ifdef CONFIG_ARCH_RANDOM
1771 	{
1772 		.desc = "Random Number Generator",
1773 		.capability = ARM64_HAS_RNG,
1774 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1775 		.matches = has_cpuid_feature,
1776 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1777 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
1778 		.sign = FTR_UNSIGNED,
1779 		.min_field_value = 1,
1780 	},
1781 #endif
1782 	{},
1783 };
1784 
1785 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
1786 		.matches = has_cpuid_feature,					\
1787 		.sys_reg = reg,							\
1788 		.field_pos = field,						\
1789 		.sign = s,							\
1790 		.min_field_value = min_value,
1791 
1792 #define __HWCAP_CAP(name, cap_type, cap)					\
1793 		.desc = name,							\
1794 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
1795 		.hwcap_type = cap_type,						\
1796 		.hwcap = cap,							\
1797 
1798 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
1799 	{									\
1800 		__HWCAP_CAP(#cap, cap_type, cap)				\
1801 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
1802 	}
1803 
1804 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
1805 	{									\
1806 		__HWCAP_CAP(#cap, cap_type, cap)				\
1807 		.matches = cpucap_multi_entry_cap_matches,			\
1808 		.match_list = list,						\
1809 	}
1810 
1811 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
1812 	{									\
1813 		__HWCAP_CAP(#cap, cap_type, cap)				\
1814 		.matches = match,						\
1815 	}
1816 
1817 #ifdef CONFIG_ARM64_PTR_AUTH
1818 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
1819 	{
1820 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
1821 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
1822 	},
1823 	{
1824 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
1825 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
1826 	},
1827 	{},
1828 };
1829 
1830 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
1831 	{
1832 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
1833 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
1834 	},
1835 	{
1836 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
1837 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
1838 	},
1839 	{},
1840 };
1841 #endif
1842 
1843 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
1844 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
1845 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
1846 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
1847 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
1848 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
1849 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
1850 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
1851 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
1852 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
1853 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
1854 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
1855 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
1856 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
1857 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
1858 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
1859 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
1860 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
1861 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
1862 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
1863 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
1864 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
1865 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
1866 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
1867 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
1868 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
1869 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
1870 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
1871 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
1872 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
1873 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
1874 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
1875 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
1876 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
1877 #ifdef CONFIG_ARM64_SVE
1878 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
1879 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
1880 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
1881 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
1882 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
1883 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
1884 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
1885 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
1886 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
1887 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
1888 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
1889 #endif
1890 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
1891 #ifdef CONFIG_ARM64_PTR_AUTH
1892 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
1893 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
1894 #endif
1895 	{},
1896 };
1897 
1898 #ifdef CONFIG_COMPAT
1899 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
1900 {
1901 	/*
1902 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
1903 	 * in line with that of arm32 as in vfp_init(). We make sure that the
1904 	 * check is future proof, by making sure value is non-zero.
1905 	 */
1906 	u32 mvfr1;
1907 
1908 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1909 	if (scope == SCOPE_SYSTEM)
1910 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
1911 	else
1912 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
1913 
1914 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
1915 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
1916 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
1917 }
1918 #endif
1919 
1920 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
1921 #ifdef CONFIG_COMPAT
1922 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
1923 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
1924 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
1925 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
1926 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
1927 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
1928 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
1929 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
1930 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
1931 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
1932 #endif
1933 	{},
1934 };
1935 
1936 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1937 {
1938 	switch (cap->hwcap_type) {
1939 	case CAP_HWCAP:
1940 		cpu_set_feature(cap->hwcap);
1941 		break;
1942 #ifdef CONFIG_COMPAT
1943 	case CAP_COMPAT_HWCAP:
1944 		compat_elf_hwcap |= (u32)cap->hwcap;
1945 		break;
1946 	case CAP_COMPAT_HWCAP2:
1947 		compat_elf_hwcap2 |= (u32)cap->hwcap;
1948 		break;
1949 #endif
1950 	default:
1951 		WARN_ON(1);
1952 		break;
1953 	}
1954 }
1955 
1956 /* Check if we have a particular HWCAP enabled */
1957 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1958 {
1959 	bool rc;
1960 
1961 	switch (cap->hwcap_type) {
1962 	case CAP_HWCAP:
1963 		rc = cpu_have_feature(cap->hwcap);
1964 		break;
1965 #ifdef CONFIG_COMPAT
1966 	case CAP_COMPAT_HWCAP:
1967 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
1968 		break;
1969 	case CAP_COMPAT_HWCAP2:
1970 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
1971 		break;
1972 #endif
1973 	default:
1974 		WARN_ON(1);
1975 		rc = false;
1976 	}
1977 
1978 	return rc;
1979 }
1980 
1981 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
1982 {
1983 	/* We support emulation of accesses to CPU ID feature registers */
1984 	cpu_set_named_feature(CPUID);
1985 	for (; hwcaps->matches; hwcaps++)
1986 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
1987 			cap_set_elf_hwcap(hwcaps);
1988 }
1989 
1990 static void update_cpu_capabilities(u16 scope_mask)
1991 {
1992 	int i;
1993 	const struct arm64_cpu_capabilities *caps;
1994 
1995 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1996 	for (i = 0; i < ARM64_NCAPS; i++) {
1997 		caps = cpu_hwcaps_ptrs[i];
1998 		if (!caps || !(caps->type & scope_mask) ||
1999 		    cpus_have_cap(caps->capability) ||
2000 		    !caps->matches(caps, cpucap_default_scope(caps)))
2001 			continue;
2002 
2003 		if (caps->desc)
2004 			pr_info("detected: %s\n", caps->desc);
2005 		cpus_set_cap(caps->capability);
2006 
2007 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2008 			set_bit(caps->capability, boot_capabilities);
2009 	}
2010 }
2011 
2012 /*
2013  * Enable all the available capabilities on this CPU. The capabilities
2014  * with BOOT_CPU scope are handled separately and hence skipped here.
2015  */
2016 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2017 {
2018 	int i;
2019 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2020 
2021 	for_each_available_cap(i) {
2022 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2023 
2024 		if (WARN_ON(!cap))
2025 			continue;
2026 
2027 		if (!(cap->type & non_boot_scope))
2028 			continue;
2029 
2030 		if (cap->cpu_enable)
2031 			cap->cpu_enable(cap);
2032 	}
2033 	return 0;
2034 }
2035 
2036 /*
2037  * Run through the enabled capabilities and enable() it on all active
2038  * CPUs
2039  */
2040 static void __init enable_cpu_capabilities(u16 scope_mask)
2041 {
2042 	int i;
2043 	const struct arm64_cpu_capabilities *caps;
2044 	bool boot_scope;
2045 
2046 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2047 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2048 
2049 	for (i = 0; i < ARM64_NCAPS; i++) {
2050 		unsigned int num;
2051 
2052 		caps = cpu_hwcaps_ptrs[i];
2053 		if (!caps || !(caps->type & scope_mask))
2054 			continue;
2055 		num = caps->capability;
2056 		if (!cpus_have_cap(num))
2057 			continue;
2058 
2059 		/* Ensure cpus_have_const_cap(num) works */
2060 		static_branch_enable(&cpu_hwcap_keys[num]);
2061 
2062 		if (boot_scope && caps->cpu_enable)
2063 			/*
2064 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2065 			 * before any secondary CPU boots. Thus, each secondary
2066 			 * will enable the capability as appropriate via
2067 			 * check_local_cpu_capabilities(). The only exception is
2068 			 * the boot CPU, for which the capability must be
2069 			 * enabled here. This approach avoids costly
2070 			 * stop_machine() calls for this case.
2071 			 */
2072 			caps->cpu_enable(caps);
2073 	}
2074 
2075 	/*
2076 	 * For all non-boot scope capabilities, use stop_machine()
2077 	 * as it schedules the work allowing us to modify PSTATE,
2078 	 * instead of on_each_cpu() which uses an IPI, giving us a
2079 	 * PSTATE that disappears when we return.
2080 	 */
2081 	if (!boot_scope)
2082 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2083 			     NULL, cpu_online_mask);
2084 }
2085 
2086 /*
2087  * Run through the list of capabilities to check for conflicts.
2088  * If the system has already detected a capability, take necessary
2089  * action on this CPU.
2090  */
2091 static void verify_local_cpu_caps(u16 scope_mask)
2092 {
2093 	int i;
2094 	bool cpu_has_cap, system_has_cap;
2095 	const struct arm64_cpu_capabilities *caps;
2096 
2097 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2098 
2099 	for (i = 0; i < ARM64_NCAPS; i++) {
2100 		caps = cpu_hwcaps_ptrs[i];
2101 		if (!caps || !(caps->type & scope_mask))
2102 			continue;
2103 
2104 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2105 		system_has_cap = cpus_have_cap(caps->capability);
2106 
2107 		if (system_has_cap) {
2108 			/*
2109 			 * Check if the new CPU misses an advertised feature,
2110 			 * which is not safe to miss.
2111 			 */
2112 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2113 				break;
2114 			/*
2115 			 * We have to issue cpu_enable() irrespective of
2116 			 * whether the CPU has it or not, as it is enabeld
2117 			 * system wide. It is upto the call back to take
2118 			 * appropriate action on this CPU.
2119 			 */
2120 			if (caps->cpu_enable)
2121 				caps->cpu_enable(caps);
2122 		} else {
2123 			/*
2124 			 * Check if the CPU has this capability if it isn't
2125 			 * safe to have when the system doesn't.
2126 			 */
2127 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2128 				break;
2129 		}
2130 	}
2131 
2132 	if (i < ARM64_NCAPS) {
2133 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2134 			smp_processor_id(), caps->capability,
2135 			caps->desc, system_has_cap, cpu_has_cap);
2136 
2137 		if (cpucap_panic_on_conflict(caps))
2138 			cpu_panic_kernel();
2139 		else
2140 			cpu_die_early();
2141 	}
2142 }
2143 
2144 /*
2145  * Check for CPU features that are used in early boot
2146  * based on the Boot CPU value.
2147  */
2148 static void check_early_cpu_features(void)
2149 {
2150 	verify_cpu_asid_bits();
2151 
2152 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2153 }
2154 
2155 static void
2156 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2157 {
2158 
2159 	for (; caps->matches; caps++)
2160 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2161 			pr_crit("CPU%d: missing HWCAP: %s\n",
2162 					smp_processor_id(), caps->desc);
2163 			cpu_die_early();
2164 		}
2165 }
2166 
2167 static void verify_sve_features(void)
2168 {
2169 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2170 	u64 zcr = read_zcr_features();
2171 
2172 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2173 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2174 
2175 	if (len < safe_len || sve_verify_vq_map()) {
2176 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2177 			smp_processor_id());
2178 		cpu_die_early();
2179 	}
2180 
2181 	/* Add checks on other ZCR bits here if necessary */
2182 }
2183 
2184 
2185 /*
2186  * Run through the enabled system capabilities and enable() it on this CPU.
2187  * The capabilities were decided based on the available CPUs at the boot time.
2188  * Any new CPU should match the system wide status of the capability. If the
2189  * new CPU doesn't have a capability which the system now has enabled, we
2190  * cannot do anything to fix it up and could cause unexpected failures. So
2191  * we park the CPU.
2192  */
2193 static void verify_local_cpu_capabilities(void)
2194 {
2195 	/*
2196 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2197 	 * check_early_cpu_features(), as they need to be verified
2198 	 * on all secondary CPUs.
2199 	 */
2200 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2201 
2202 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
2203 
2204 	if (system_supports_32bit_el0())
2205 		verify_local_elf_hwcaps(compat_elf_hwcaps);
2206 
2207 	if (system_supports_sve())
2208 		verify_sve_features();
2209 }
2210 
2211 void check_local_cpu_capabilities(void)
2212 {
2213 	/*
2214 	 * All secondary CPUs should conform to the early CPU features
2215 	 * in use by the kernel based on boot CPU.
2216 	 */
2217 	check_early_cpu_features();
2218 
2219 	/*
2220 	 * If we haven't finalised the system capabilities, this CPU gets
2221 	 * a chance to update the errata work arounds and local features.
2222 	 * Otherwise, this CPU should verify that it has all the system
2223 	 * advertised capabilities.
2224 	 */
2225 	if (!system_capabilities_finalized())
2226 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2227 	else
2228 		verify_local_cpu_capabilities();
2229 }
2230 
2231 static void __init setup_boot_cpu_capabilities(void)
2232 {
2233 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2234 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2235 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2236 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2237 }
2238 
2239 bool this_cpu_has_cap(unsigned int n)
2240 {
2241 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2242 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2243 
2244 		if (cap)
2245 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2246 	}
2247 
2248 	return false;
2249 }
2250 
2251 /*
2252  * This helper function is used in a narrow window when,
2253  * - The system wide safe registers are set with all the SMP CPUs and,
2254  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2255  * In all other cases cpus_have_{const_}cap() should be used.
2256  */
2257 static bool __system_matches_cap(unsigned int n)
2258 {
2259 	if (n < ARM64_NCAPS) {
2260 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2261 
2262 		if (cap)
2263 			return cap->matches(cap, SCOPE_SYSTEM);
2264 	}
2265 	return false;
2266 }
2267 
2268 void cpu_set_feature(unsigned int num)
2269 {
2270 	WARN_ON(num >= MAX_CPU_FEATURES);
2271 	elf_hwcap |= BIT(num);
2272 }
2273 EXPORT_SYMBOL_GPL(cpu_set_feature);
2274 
2275 bool cpu_have_feature(unsigned int num)
2276 {
2277 	WARN_ON(num >= MAX_CPU_FEATURES);
2278 	return elf_hwcap & BIT(num);
2279 }
2280 EXPORT_SYMBOL_GPL(cpu_have_feature);
2281 
2282 unsigned long cpu_get_elf_hwcap(void)
2283 {
2284 	/*
2285 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2286 	 * note that for userspace compatibility we guarantee that bits 62
2287 	 * and 63 will always be returned as 0.
2288 	 */
2289 	return lower_32_bits(elf_hwcap);
2290 }
2291 
2292 unsigned long cpu_get_elf_hwcap2(void)
2293 {
2294 	return upper_32_bits(elf_hwcap);
2295 }
2296 
2297 static void __init setup_system_capabilities(void)
2298 {
2299 	/*
2300 	 * We have finalised the system-wide safe feature
2301 	 * registers, finalise the capabilities that depend
2302 	 * on it. Also enable all the available capabilities,
2303 	 * that are not enabled already.
2304 	 */
2305 	update_cpu_capabilities(SCOPE_SYSTEM);
2306 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2307 }
2308 
2309 void __init setup_cpu_features(void)
2310 {
2311 	u32 cwg;
2312 
2313 	setup_system_capabilities();
2314 	setup_elf_hwcaps(arm64_elf_hwcaps);
2315 
2316 	if (system_supports_32bit_el0())
2317 		setup_elf_hwcaps(compat_elf_hwcaps);
2318 
2319 	if (system_uses_ttbr0_pan())
2320 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2321 
2322 	sve_setup();
2323 	minsigstksz_setup();
2324 
2325 	/* Advertise that we have computed the system capabilities */
2326 	finalize_system_capabilities();
2327 
2328 	/*
2329 	 * Check for sane CTR_EL0.CWG value.
2330 	 */
2331 	cwg = cache_type_cwg();
2332 	if (!cwg)
2333 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2334 			ARCH_DMA_MINALIGN);
2335 }
2336 
2337 static bool __maybe_unused
2338 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
2339 {
2340 	return (__system_matches_cap(ARM64_HAS_PAN) && !__system_matches_cap(ARM64_HAS_UAO));
2341 }
2342 
2343 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2344 {
2345 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2346 }
2347 
2348 /*
2349  * We emulate only the following system register space.
2350  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2351  * See Table C5-6 System instruction encodings for System register accesses,
2352  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2353  */
2354 static inline bool __attribute_const__ is_emulated(u32 id)
2355 {
2356 	return (sys_reg_Op0(id) == 0x3 &&
2357 		sys_reg_CRn(id) == 0x0 &&
2358 		sys_reg_Op1(id) == 0x0 &&
2359 		(sys_reg_CRm(id) == 0 ||
2360 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2361 }
2362 
2363 /*
2364  * With CRm == 0, reg should be one of :
2365  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2366  */
2367 static inline int emulate_id_reg(u32 id, u64 *valp)
2368 {
2369 	switch (id) {
2370 	case SYS_MIDR_EL1:
2371 		*valp = read_cpuid_id();
2372 		break;
2373 	case SYS_MPIDR_EL1:
2374 		*valp = SYS_MPIDR_SAFE_VAL;
2375 		break;
2376 	case SYS_REVIDR_EL1:
2377 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2378 		*valp = 0;
2379 		break;
2380 	default:
2381 		return -EINVAL;
2382 	}
2383 
2384 	return 0;
2385 }
2386 
2387 static int emulate_sys_reg(u32 id, u64 *valp)
2388 {
2389 	struct arm64_ftr_reg *regp;
2390 
2391 	if (!is_emulated(id))
2392 		return -EINVAL;
2393 
2394 	if (sys_reg_CRm(id) == 0)
2395 		return emulate_id_reg(id, valp);
2396 
2397 	regp = get_arm64_ftr_reg(id);
2398 	if (regp)
2399 		*valp = arm64_ftr_reg_user_value(regp);
2400 	else
2401 		/*
2402 		 * The untracked registers are either IMPLEMENTATION DEFINED
2403 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2404 		 */
2405 		*valp = 0;
2406 	return 0;
2407 }
2408 
2409 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2410 {
2411 	int rc;
2412 	u64 val;
2413 
2414 	rc = emulate_sys_reg(sys_reg, &val);
2415 	if (!rc) {
2416 		pt_regs_write_reg(regs, rt, val);
2417 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2418 	}
2419 	return rc;
2420 }
2421 
2422 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2423 {
2424 	u32 sys_reg, rt;
2425 
2426 	/*
2427 	 * sys_reg values are defined as used in mrs/msr instruction.
2428 	 * shift the imm value to get the encoding.
2429 	 */
2430 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2431 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2432 	return do_emulate_mrs(regs, sys_reg, rt);
2433 }
2434 
2435 static struct undef_hook mrs_hook = {
2436 	.instr_mask = 0xfff00000,
2437 	.instr_val  = 0xd5300000,
2438 	.pstate_mask = PSR_AA32_MODE_MASK,
2439 	.pstate_val = PSR_MODE_EL0t,
2440 	.fn = emulate_mrs,
2441 };
2442 
2443 static int __init enable_mrs_emulation(void)
2444 {
2445 	register_undef_hook(&mrs_hook);
2446 	return 0;
2447 }
2448 
2449 core_initcall(enable_mrs_emulation);
2450 
2451 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
2452 			  char *buf)
2453 {
2454 	if (__meltdown_safe)
2455 		return sprintf(buf, "Not affected\n");
2456 
2457 	if (arm64_kernel_unmapped_at_el0())
2458 		return sprintf(buf, "Mitigation: PTI\n");
2459 
2460 	return sprintf(buf, "Vulnerable\n");
2461 }
2462