xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision 8440bb9b)
1 /*
2  * Contains CPU feature definitions
3  *
4  * Copyright (C) 2015 ARM Ltd.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #define pr_fmt(fmt) "CPU features: " fmt
20 
21 #include <linux/bsearch.h>
22 #include <linux/cpumask.h>
23 #include <linux/crash_dump.h>
24 #include <linux/sort.h>
25 #include <linux/stop_machine.h>
26 #include <linux/types.h>
27 #include <linux/mm.h>
28 #include <asm/cpu.h>
29 #include <asm/cpufeature.h>
30 #include <asm/cpu_ops.h>
31 #include <asm/fpsimd.h>
32 #include <asm/mmu_context.h>
33 #include <asm/processor.h>
34 #include <asm/sysreg.h>
35 #include <asm/traps.h>
36 #include <asm/virt.h>
37 
38 unsigned long elf_hwcap __read_mostly;
39 EXPORT_SYMBOL_GPL(elf_hwcap);
40 
41 #ifdef CONFIG_COMPAT
42 #define COMPAT_ELF_HWCAP_DEFAULT	\
43 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
44 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
45 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
46 				 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
47 				 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
48 				 COMPAT_HWCAP_LPAE)
49 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
50 unsigned int compat_elf_hwcap2 __read_mostly;
51 #endif
52 
53 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
54 EXPORT_SYMBOL(cpu_hwcaps);
55 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
56 
57 /* Need also bit for ARM64_CB_PATCH */
58 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
59 
60 /*
61  * Flag to indicate if we have computed the system wide
62  * capabilities based on the boot time active CPUs. This
63  * will be used to determine if a new booting CPU should
64  * go through the verification process to make sure that it
65  * supports the system capabilities, without using a hotplug
66  * notifier.
67  */
68 static bool sys_caps_initialised;
69 
70 static inline void set_sys_caps_initialised(void)
71 {
72 	sys_caps_initialised = true;
73 }
74 
75 static int dump_cpu_hwcaps(struct notifier_block *self, unsigned long v, void *p)
76 {
77 	/* file-wide pr_fmt adds "CPU features: " prefix */
78 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
79 	return 0;
80 }
81 
82 static struct notifier_block cpu_hwcaps_notifier = {
83 	.notifier_call = dump_cpu_hwcaps
84 };
85 
86 static int __init register_cpu_hwcaps_dumper(void)
87 {
88 	atomic_notifier_chain_register(&panic_notifier_list,
89 				       &cpu_hwcaps_notifier);
90 	return 0;
91 }
92 __initcall(register_cpu_hwcaps_dumper);
93 
94 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
95 EXPORT_SYMBOL(cpu_hwcap_keys);
96 
97 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
98 	{						\
99 		.sign = SIGNED,				\
100 		.visible = VISIBLE,			\
101 		.strict = STRICT,			\
102 		.type = TYPE,				\
103 		.shift = SHIFT,				\
104 		.width = WIDTH,				\
105 		.safe_val = SAFE_VAL,			\
106 	}
107 
108 /* Define a feature with unsigned values */
109 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
110 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
111 
112 /* Define a feature with a signed value */
113 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
114 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
115 
116 #define ARM64_FTR_END					\
117 	{						\
118 		.width = 0,				\
119 	}
120 
121 /* meta feature for alternatives */
122 static bool __maybe_unused
123 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
124 
125 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
126 
127 /*
128  * NOTE: Any changes to the visibility of features should be kept in
129  * sync with the documentation of the CPU feature register ABI.
130  */
131 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
132 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
133 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
134 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
135 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
136 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
137 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
138 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
139 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
140 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
141 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
142 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
143 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
144 	ARM64_FTR_END,
145 };
146 
147 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
148 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_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_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
169 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
170 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
171 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
172 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
173 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
174 	/* Linux doesn't care about the EL3 */
175 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
176 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
178 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
179 	ARM64_FTR_END,
180 };
181 
182 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
183 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
184 	ARM64_FTR_END,
185 };
186 
187 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
188 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
189 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
190 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
191 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
192 	/* Linux shouldn't care about secure memory */
193 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
196 	/*
197 	 * Differing PARange is fine as long as all peripherals and memory are mapped
198 	 * within the minimum PARange of all CPUs
199 	 */
200 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
201 	ARM64_FTR_END,
202 };
203 
204 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
205 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
211 	ARM64_FTR_END,
212 };
213 
214 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
215 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
221 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
222 	ARM64_FTR_END,
223 };
224 
225 static const struct arm64_ftr_bits ftr_ctr[] = {
226 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
227 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
228 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
229 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, CTR_CWG_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, CTR_ERG_SHIFT, 4, 0),
231 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
232 	/*
233 	 * Linux can handle differing I-cache policies. Userspace JITs will
234 	 * make use of *minLine.
235 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
236 	 */
237 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
238 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
239 	ARM64_FTR_END,
240 };
241 
242 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
243 	.name		= "SYS_CTR_EL0",
244 	.ftr_bits	= ftr_ctr
245 };
246 
247 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
248 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0xf),	/* InnerShr */
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),	/* FCSE */
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* AuxReg */
251 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),	/* TCM */
252 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),	/* ShareLvl */
253 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0xf),	/* OuterShr */
254 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),	/* PMSA */
255 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* VMSA */
256 	ARM64_FTR_END,
257 };
258 
259 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
260 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 36, 28, 0),
261 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
263 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
264 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
265 	/*
266 	 * We can instantiate multiple PMU instances with different levels
267 	 * of support.
268 	 */
269 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
270 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
271 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
272 	ARM64_FTR_END,
273 };
274 
275 static const struct arm64_ftr_bits ftr_mvfr2[] = {
276 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),		/* FPMisc */
277 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),		/* SIMDMisc */
278 	ARM64_FTR_END,
279 };
280 
281 static const struct arm64_ftr_bits ftr_dczid[] = {
282 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 4, 1, 1),		/* DZP */
283 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* BS */
284 	ARM64_FTR_END,
285 };
286 
287 
288 static const struct arm64_ftr_bits ftr_id_isar5[] = {
289 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
290 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
291 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
292 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
293 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
294 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
295 	ARM64_FTR_END,
296 };
297 
298 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
299 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),	/* ac2 */
300 	ARM64_FTR_END,
301 };
302 
303 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
304 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),		/* State3 */
305 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),		/* State2 */
306 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),		/* State1 */
307 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),		/* State0 */
308 	ARM64_FTR_END,
309 };
310 
311 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
312 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
313 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf),	/* PerfMon */
314 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
315 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
316 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
317 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
318 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
319 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
320 	ARM64_FTR_END,
321 };
322 
323 static const struct arm64_ftr_bits ftr_zcr[] = {
324 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
325 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
326 	ARM64_FTR_END,
327 };
328 
329 /*
330  * Common ftr bits for a 32bit register with all hidden, strict
331  * attributes, with 4bit feature fields and a default safe value of
332  * 0. Covers the following 32bit registers:
333  * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
334  */
335 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
344 	ARM64_FTR_END,
345 };
346 
347 /* Table for a single 32bit feature value */
348 static const struct arm64_ftr_bits ftr_single32[] = {
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
350 	ARM64_FTR_END,
351 };
352 
353 static const struct arm64_ftr_bits ftr_raz[] = {
354 	ARM64_FTR_END,
355 };
356 
357 #define ARM64_FTR_REG(id, table) {		\
358 	.sys_id = id,				\
359 	.reg = 	&(struct arm64_ftr_reg){	\
360 		.name = #id,			\
361 		.ftr_bits = &((table)[0]),	\
362 	}}
363 
364 static const struct __ftr_reg_entry {
365 	u32			sys_id;
366 	struct arm64_ftr_reg 	*reg;
367 } arm64_ftr_regs[] = {
368 
369 	/* Op1 = 0, CRn = 0, CRm = 1 */
370 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
371 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
372 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
373 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
374 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
375 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
376 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
377 
378 	/* Op1 = 0, CRn = 0, CRm = 2 */
379 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
380 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
381 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
382 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
383 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
384 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
385 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
386 
387 	/* Op1 = 0, CRn = 0, CRm = 3 */
388 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
389 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
390 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
391 
392 	/* Op1 = 0, CRn = 0, CRm = 4 */
393 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
394 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
395 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_raz),
396 
397 	/* Op1 = 0, CRn = 0, CRm = 5 */
398 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
399 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
400 
401 	/* Op1 = 0, CRn = 0, CRm = 6 */
402 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
403 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
404 
405 	/* Op1 = 0, CRn = 0, CRm = 7 */
406 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
407 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
408 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
409 
410 	/* Op1 = 0, CRn = 1, CRm = 2 */
411 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
412 
413 	/* Op1 = 3, CRn = 0, CRm = 0 */
414 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
415 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
416 
417 	/* Op1 = 3, CRn = 14, CRm = 0 */
418 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
419 };
420 
421 static int search_cmp_ftr_reg(const void *id, const void *regp)
422 {
423 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
424 }
425 
426 /*
427  * get_arm64_ftr_reg - Lookup a feature register entry using its
428  * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
429  * ascending order of sys_id , we use binary search to find a matching
430  * entry.
431  *
432  * returns - Upon success,  matching ftr_reg entry for id.
433  *         - NULL on failure. It is upto the caller to decide
434  *	     the impact of a failure.
435  */
436 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
437 {
438 	const struct __ftr_reg_entry *ret;
439 
440 	ret = bsearch((const void *)(unsigned long)sys_id,
441 			arm64_ftr_regs,
442 			ARRAY_SIZE(arm64_ftr_regs),
443 			sizeof(arm64_ftr_regs[0]),
444 			search_cmp_ftr_reg);
445 	if (ret)
446 		return ret->reg;
447 	return NULL;
448 }
449 
450 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
451 			       s64 ftr_val)
452 {
453 	u64 mask = arm64_ftr_mask(ftrp);
454 
455 	reg &= ~mask;
456 	reg |= (ftr_val << ftrp->shift) & mask;
457 	return reg;
458 }
459 
460 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
461 				s64 cur)
462 {
463 	s64 ret = 0;
464 
465 	switch (ftrp->type) {
466 	case FTR_EXACT:
467 		ret = ftrp->safe_val;
468 		break;
469 	case FTR_LOWER_SAFE:
470 		ret = new < cur ? new : cur;
471 		break;
472 	case FTR_HIGHER_SAFE:
473 		ret = new > cur ? new : cur;
474 		break;
475 	default:
476 		BUG();
477 	}
478 
479 	return ret;
480 }
481 
482 static void __init sort_ftr_regs(void)
483 {
484 	int i;
485 
486 	/* Check that the array is sorted so that we can do the binary search */
487 	for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++)
488 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
489 }
490 
491 /*
492  * Initialise the CPU feature register from Boot CPU values.
493  * Also initiliases the strict_mask for the register.
494  * Any bits that are not covered by an arm64_ftr_bits entry are considered
495  * RES0 for the system-wide value, and must strictly match.
496  */
497 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
498 {
499 	u64 val = 0;
500 	u64 strict_mask = ~0x0ULL;
501 	u64 user_mask = 0;
502 	u64 valid_mask = 0;
503 
504 	const struct arm64_ftr_bits *ftrp;
505 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
506 
507 	BUG_ON(!reg);
508 
509 	for (ftrp  = reg->ftr_bits; ftrp->width; ftrp++) {
510 		u64 ftr_mask = arm64_ftr_mask(ftrp);
511 		s64 ftr_new = arm64_ftr_value(ftrp, new);
512 
513 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
514 
515 		valid_mask |= ftr_mask;
516 		if (!ftrp->strict)
517 			strict_mask &= ~ftr_mask;
518 		if (ftrp->visible)
519 			user_mask |= ftr_mask;
520 		else
521 			reg->user_val = arm64_ftr_set_value(ftrp,
522 							    reg->user_val,
523 							    ftrp->safe_val);
524 	}
525 
526 	val &= valid_mask;
527 
528 	reg->sys_val = val;
529 	reg->strict_mask = strict_mask;
530 	reg->user_mask = user_mask;
531 }
532 
533 extern const struct arm64_cpu_capabilities arm64_errata[];
534 static const struct arm64_cpu_capabilities arm64_features[];
535 
536 static void __init
537 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
538 {
539 	for (; caps->matches; caps++) {
540 		if (WARN(caps->capability >= ARM64_NCAPS,
541 			"Invalid capability %d\n", caps->capability))
542 			continue;
543 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
544 			"Duplicate entry for capability %d\n",
545 			caps->capability))
546 			continue;
547 		cpu_hwcaps_ptrs[caps->capability] = caps;
548 	}
549 }
550 
551 static void __init init_cpu_hwcaps_indirect_list(void)
552 {
553 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
554 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
555 }
556 
557 static void __init setup_boot_cpu_capabilities(void);
558 
559 void __init init_cpu_features(struct cpuinfo_arm64 *info)
560 {
561 	/* Before we start using the tables, make sure it is sorted */
562 	sort_ftr_regs();
563 
564 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
565 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
566 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
567 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
568 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
569 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
570 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
571 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
572 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
573 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
574 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
575 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
576 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
577 
578 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
579 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
580 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
581 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
582 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
583 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
584 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
585 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
586 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
587 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
588 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
589 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
590 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
591 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
592 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
593 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
594 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
595 	}
596 
597 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
598 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
599 		sve_init_vq_map();
600 	}
601 
602 	/*
603 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
604 	 * before we handle the boot CPU below.
605 	 */
606 	init_cpu_hwcaps_indirect_list();
607 
608 	/*
609 	 * Detect and enable early CPU capabilities based on the boot CPU,
610 	 * after we have initialised the CPU feature infrastructure.
611 	 */
612 	setup_boot_cpu_capabilities();
613 }
614 
615 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
616 {
617 	const struct arm64_ftr_bits *ftrp;
618 
619 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
620 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
621 		s64 ftr_new = arm64_ftr_value(ftrp, new);
622 
623 		if (ftr_cur == ftr_new)
624 			continue;
625 		/* Find a safe value */
626 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
627 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
628 	}
629 
630 }
631 
632 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
633 {
634 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
635 
636 	BUG_ON(!regp);
637 	update_cpu_ftr_reg(regp, val);
638 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
639 		return 0;
640 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
641 			regp->name, boot, cpu, val);
642 	return 1;
643 }
644 
645 /*
646  * Update system wide CPU feature registers with the values from a
647  * non-boot CPU. Also performs SANITY checks to make sure that there
648  * aren't any insane variations from that of the boot CPU.
649  */
650 void update_cpu_features(int cpu,
651 			 struct cpuinfo_arm64 *info,
652 			 struct cpuinfo_arm64 *boot)
653 {
654 	int taint = 0;
655 
656 	/*
657 	 * The kernel can handle differing I-cache policies, but otherwise
658 	 * caches should look identical. Userspace JITs will make use of
659 	 * *minLine.
660 	 */
661 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
662 				      info->reg_ctr, boot->reg_ctr);
663 
664 	/*
665 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
666 	 * could result in too much or too little memory being zeroed if a
667 	 * process is preempted and migrated between CPUs.
668 	 */
669 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
670 				      info->reg_dczid, boot->reg_dczid);
671 
672 	/* If different, timekeeping will be broken (especially with KVM) */
673 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
674 				      info->reg_cntfrq, boot->reg_cntfrq);
675 
676 	/*
677 	 * The kernel uses self-hosted debug features and expects CPUs to
678 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
679 	 * and BRPs to be identical.
680 	 * ID_AA64DFR1 is currently RES0.
681 	 */
682 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
683 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
684 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
685 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
686 	/*
687 	 * Even in big.LITTLE, processors should be identical instruction-set
688 	 * wise.
689 	 */
690 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
691 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
692 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
693 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
694 
695 	/*
696 	 * Differing PARange support is fine as long as all peripherals and
697 	 * memory are mapped within the minimum PARange of all CPUs.
698 	 * Linux should not care about secure memory.
699 	 */
700 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
701 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
702 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
703 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
704 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
705 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
706 
707 	/*
708 	 * EL3 is not our concern.
709 	 */
710 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
711 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
712 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
713 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
714 
715 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
716 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
717 
718 	/*
719 	 * If we have AArch32, we care about 32-bit features for compat.
720 	 * If the system doesn't support AArch32, don't update them.
721 	 */
722 	if (id_aa64pfr0_32bit_el0(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
723 		id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
724 
725 		taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
726 					info->reg_id_dfr0, boot->reg_id_dfr0);
727 		taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
728 					info->reg_id_isar0, boot->reg_id_isar0);
729 		taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
730 					info->reg_id_isar1, boot->reg_id_isar1);
731 		taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
732 					info->reg_id_isar2, boot->reg_id_isar2);
733 		taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
734 					info->reg_id_isar3, boot->reg_id_isar3);
735 		taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
736 					info->reg_id_isar4, boot->reg_id_isar4);
737 		taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
738 					info->reg_id_isar5, boot->reg_id_isar5);
739 
740 		/*
741 		 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
742 		 * ACTLR formats could differ across CPUs and therefore would have to
743 		 * be trapped for virtualization anyway.
744 		 */
745 		taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
746 					info->reg_id_mmfr0, boot->reg_id_mmfr0);
747 		taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
748 					info->reg_id_mmfr1, boot->reg_id_mmfr1);
749 		taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
750 					info->reg_id_mmfr2, boot->reg_id_mmfr2);
751 		taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
752 					info->reg_id_mmfr3, boot->reg_id_mmfr3);
753 		taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
754 					info->reg_id_pfr0, boot->reg_id_pfr0);
755 		taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
756 					info->reg_id_pfr1, boot->reg_id_pfr1);
757 		taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
758 					info->reg_mvfr0, boot->reg_mvfr0);
759 		taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
760 					info->reg_mvfr1, boot->reg_mvfr1);
761 		taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
762 					info->reg_mvfr2, boot->reg_mvfr2);
763 	}
764 
765 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
766 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
767 					info->reg_zcr, boot->reg_zcr);
768 
769 		/* Probe vector lengths, unless we already gave up on SVE */
770 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
771 		    !sys_caps_initialised)
772 			sve_update_vq_map();
773 	}
774 
775 	/*
776 	 * Mismatched CPU features are a recipe for disaster. Don't even
777 	 * pretend to support them.
778 	 */
779 	if (taint) {
780 		pr_warn_once("Unsupported CPU feature variation detected.\n");
781 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
782 	}
783 }
784 
785 u64 read_sanitised_ftr_reg(u32 id)
786 {
787 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
788 
789 	/* We shouldn't get a request for an unsupported register */
790 	BUG_ON(!regp);
791 	return regp->sys_val;
792 }
793 
794 #define read_sysreg_case(r)	\
795 	case r:		return read_sysreg_s(r)
796 
797 /*
798  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
799  * Read the system register on the current CPU
800  */
801 static u64 __read_sysreg_by_encoding(u32 sys_id)
802 {
803 	switch (sys_id) {
804 	read_sysreg_case(SYS_ID_PFR0_EL1);
805 	read_sysreg_case(SYS_ID_PFR1_EL1);
806 	read_sysreg_case(SYS_ID_DFR0_EL1);
807 	read_sysreg_case(SYS_ID_MMFR0_EL1);
808 	read_sysreg_case(SYS_ID_MMFR1_EL1);
809 	read_sysreg_case(SYS_ID_MMFR2_EL1);
810 	read_sysreg_case(SYS_ID_MMFR3_EL1);
811 	read_sysreg_case(SYS_ID_ISAR0_EL1);
812 	read_sysreg_case(SYS_ID_ISAR1_EL1);
813 	read_sysreg_case(SYS_ID_ISAR2_EL1);
814 	read_sysreg_case(SYS_ID_ISAR3_EL1);
815 	read_sysreg_case(SYS_ID_ISAR4_EL1);
816 	read_sysreg_case(SYS_ID_ISAR5_EL1);
817 	read_sysreg_case(SYS_MVFR0_EL1);
818 	read_sysreg_case(SYS_MVFR1_EL1);
819 	read_sysreg_case(SYS_MVFR2_EL1);
820 
821 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
822 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
823 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
824 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
825 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
826 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
827 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
828 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
829 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
830 
831 	read_sysreg_case(SYS_CNTFRQ_EL0);
832 	read_sysreg_case(SYS_CTR_EL0);
833 	read_sysreg_case(SYS_DCZID_EL0);
834 
835 	default:
836 		BUG();
837 		return 0;
838 	}
839 }
840 
841 #include <linux/irqchip/arm-gic-v3.h>
842 
843 static bool
844 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
845 {
846 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
847 
848 	return val >= entry->min_field_value;
849 }
850 
851 static bool
852 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
853 {
854 	u64 val;
855 
856 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
857 	if (scope == SCOPE_SYSTEM)
858 		val = read_sanitised_ftr_reg(entry->sys_reg);
859 	else
860 		val = __read_sysreg_by_encoding(entry->sys_reg);
861 
862 	return feature_matches(val, entry);
863 }
864 
865 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
866 {
867 	bool has_sre;
868 
869 	if (!has_cpuid_feature(entry, scope))
870 		return false;
871 
872 	has_sre = gic_enable_sre();
873 	if (!has_sre)
874 		pr_warn_once("%s present but disabled by higher exception level\n",
875 			     entry->desc);
876 
877 	return has_sre;
878 }
879 
880 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
881 {
882 	u32 midr = read_cpuid_id();
883 
884 	/* Cavium ThunderX pass 1.x and 2.x */
885 	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
886 		MIDR_CPU_VAR_REV(0, 0),
887 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
888 }
889 
890 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
891 {
892 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
893 
894 	return cpuid_feature_extract_signed_field(pfr0,
895 					ID_AA64PFR0_FP_SHIFT) < 0;
896 }
897 
898 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
899 			  int scope)
900 {
901 	u64 ctr;
902 
903 	if (scope == SCOPE_SYSTEM)
904 		ctr = arm64_ftr_reg_ctrel0.sys_val;
905 	else
906 		ctr = read_cpuid_effective_cachetype();
907 
908 	return ctr & BIT(CTR_IDC_SHIFT);
909 }
910 
911 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
912 {
913 	/*
914 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
915 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
916 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
917 	 * value.
918 	 */
919 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
920 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
921 }
922 
923 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
924 			  int scope)
925 {
926 	u64 ctr;
927 
928 	if (scope == SCOPE_SYSTEM)
929 		ctr = arm64_ftr_reg_ctrel0.sys_val;
930 	else
931 		ctr = read_cpuid_cachetype();
932 
933 	return ctr & BIT(CTR_DIC_SHIFT);
934 }
935 
936 static bool __maybe_unused
937 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
938 {
939 	/*
940 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
941 	 * may share TLB entries with a CPU stuck in the crashed
942 	 * kernel.
943 	 */
944 	 if (is_kdump_kernel())
945 		return false;
946 
947 	return has_cpuid_feature(entry, scope);
948 }
949 
950 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
951 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
952 
953 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
954 				int scope)
955 {
956 	/* List of CPUs that are not vulnerable and don't need KPTI */
957 	static const struct midr_range kpti_safe_list[] = {
958 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
959 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
960 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
961 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
962 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
963 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
964 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
965 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
966 		{ /* sentinel */ }
967 	};
968 	char const *str = "command line option";
969 
970 	/*
971 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
972 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
973 	 * ends as well as you might imagine. Don't even try.
974 	 */
975 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
976 		str = "ARM64_WORKAROUND_CAVIUM_27456";
977 		__kpti_forced = -1;
978 	}
979 
980 	/* Forced? */
981 	if (__kpti_forced) {
982 		pr_info_once("kernel page table isolation forced %s by %s\n",
983 			     __kpti_forced > 0 ? "ON" : "OFF", str);
984 		return __kpti_forced > 0;
985 	}
986 
987 	/* Useful for KASLR robustness */
988 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
989 		return kaslr_offset() > 0;
990 
991 	/* Don't force KPTI for CPUs that are not vulnerable */
992 	if (is_midr_in_range_list(read_cpuid_id(), kpti_safe_list))
993 		return false;
994 
995 	/* Defer to CPU feature registers */
996 	return !has_cpuid_feature(entry, scope);
997 }
998 
999 static void
1000 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1001 {
1002 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1003 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1004 	kpti_remap_fn *remap_fn;
1005 
1006 	static bool kpti_applied = false;
1007 	int cpu = smp_processor_id();
1008 
1009 	/*
1010 	 * We don't need to rewrite the page-tables if either we've done
1011 	 * it already or we have KASLR enabled and therefore have not
1012 	 * created any global mappings at all.
1013 	 */
1014 	if (kpti_applied || kaslr_offset() > 0)
1015 		return;
1016 
1017 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1018 
1019 	cpu_install_idmap();
1020 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1021 	cpu_uninstall_idmap();
1022 
1023 	if (!cpu)
1024 		kpti_applied = true;
1025 
1026 	return;
1027 }
1028 
1029 static int __init parse_kpti(char *str)
1030 {
1031 	bool enabled;
1032 	int ret = strtobool(str, &enabled);
1033 
1034 	if (ret)
1035 		return ret;
1036 
1037 	__kpti_forced = enabled ? 1 : -1;
1038 	return 0;
1039 }
1040 early_param("kpti", parse_kpti);
1041 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1042 
1043 #ifdef CONFIG_ARM64_HW_AFDBM
1044 static inline void __cpu_enable_hw_dbm(void)
1045 {
1046 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1047 
1048 	write_sysreg(tcr, tcr_el1);
1049 	isb();
1050 }
1051 
1052 static bool cpu_has_broken_dbm(void)
1053 {
1054 	/* List of CPUs which have broken DBM support. */
1055 	static const struct midr_range cpus[] = {
1056 #ifdef CONFIG_ARM64_ERRATUM_1024718
1057 		MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0),  // A55 r0p0 -r1p0
1058 #endif
1059 		{},
1060 	};
1061 
1062 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1063 }
1064 
1065 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1066 {
1067 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1068 	       !cpu_has_broken_dbm();
1069 }
1070 
1071 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1072 {
1073 	if (cpu_can_use_dbm(cap))
1074 		__cpu_enable_hw_dbm();
1075 }
1076 
1077 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1078 		       int __unused)
1079 {
1080 	static bool detected = false;
1081 	/*
1082 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1083 	 * run a mix of CPUs with and without the feature. So, we
1084 	 * unconditionally enable the capability to allow any late CPU
1085 	 * to use the feature. We only enable the control bits on the
1086 	 * CPU, if it actually supports.
1087 	 *
1088 	 * We have to make sure we print the "feature" detection only
1089 	 * when at least one CPU actually uses it. So check if this CPU
1090 	 * can actually use it and print the message exactly once.
1091 	 *
1092 	 * This is safe as all CPUs (including secondary CPUs - due to the
1093 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1094 	 * goes through the "matches" check exactly once. Also if a CPU
1095 	 * matches the criteria, it is guaranteed that the CPU will turn
1096 	 * the DBM on, as the capability is unconditionally enabled.
1097 	 */
1098 	if (!detected && cpu_can_use_dbm(cap)) {
1099 		detected = true;
1100 		pr_info("detected: Hardware dirty bit management\n");
1101 	}
1102 
1103 	return true;
1104 }
1105 
1106 #endif
1107 
1108 #ifdef CONFIG_ARM64_VHE
1109 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1110 {
1111 	return is_kernel_in_hyp_mode();
1112 }
1113 
1114 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1115 {
1116 	/*
1117 	 * Copy register values that aren't redirected by hardware.
1118 	 *
1119 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1120 	 * this value to tpidr_el2 before we patch the code. Once we've done
1121 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1122 	 * do anything here.
1123 	 */
1124 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1125 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1126 }
1127 #endif
1128 
1129 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1130 {
1131 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1132 
1133 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1134 	WARN_ON(val & (7 << 27 | 7 << 21));
1135 }
1136 
1137 #ifdef CONFIG_ARM64_SSBD
1138 static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr)
1139 {
1140 	if (user_mode(regs))
1141 		return 1;
1142 
1143 	if (instr & BIT(PSTATE_Imm_shift))
1144 		regs->pstate |= PSR_SSBS_BIT;
1145 	else
1146 		regs->pstate &= ~PSR_SSBS_BIT;
1147 
1148 	arm64_skip_faulting_instruction(regs, 4);
1149 	return 0;
1150 }
1151 
1152 static struct undef_hook ssbs_emulation_hook = {
1153 	.instr_mask	= ~(1U << PSTATE_Imm_shift),
1154 	.instr_val	= 0xd500401f | PSTATE_SSBS,
1155 	.fn		= ssbs_emulation_handler,
1156 };
1157 
1158 static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused)
1159 {
1160 	static bool undef_hook_registered = false;
1161 	static DEFINE_SPINLOCK(hook_lock);
1162 
1163 	spin_lock(&hook_lock);
1164 	if (!undef_hook_registered) {
1165 		register_undef_hook(&ssbs_emulation_hook);
1166 		undef_hook_registered = true;
1167 	}
1168 	spin_unlock(&hook_lock);
1169 
1170 	if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) {
1171 		sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS);
1172 		arm64_set_ssbd_mitigation(false);
1173 	} else {
1174 		arm64_set_ssbd_mitigation(true);
1175 	}
1176 }
1177 #endif /* CONFIG_ARM64_SSBD */
1178 
1179 #ifdef CONFIG_ARM64_PAN
1180 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1181 {
1182 	/*
1183 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1184 	 * is discarded once we return from the exception.
1185 	 */
1186 	WARN_ON_ONCE(in_interrupt());
1187 
1188 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1189 	asm(SET_PSTATE_PAN(1));
1190 }
1191 #endif /* CONFIG_ARM64_PAN */
1192 
1193 #ifdef CONFIG_ARM64_RAS_EXTN
1194 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1195 {
1196 	/* Firmware may have left a deferred SError in this register. */
1197 	write_sysreg_s(0, SYS_DISR_EL1);
1198 }
1199 #endif /* CONFIG_ARM64_RAS_EXTN */
1200 
1201 #ifdef CONFIG_ARM64_PTR_AUTH
1202 static void cpu_enable_address_auth(struct arm64_cpu_capabilities const *cap)
1203 {
1204 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ENIA | SCTLR_ELx_ENIB |
1205 				       SCTLR_ELx_ENDA | SCTLR_ELx_ENDB);
1206 }
1207 #endif /* CONFIG_ARM64_PTR_AUTH */
1208 
1209 #ifdef CONFIG_ARM64_PSEUDO_NMI
1210 static bool enable_pseudo_nmi;
1211 
1212 static int __init early_enable_pseudo_nmi(char *p)
1213 {
1214 	return strtobool(p, &enable_pseudo_nmi);
1215 }
1216 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1217 
1218 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1219 				   int scope)
1220 {
1221 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1222 }
1223 #endif
1224 
1225 static const struct arm64_cpu_capabilities arm64_features[] = {
1226 	{
1227 		.desc = "GIC system register CPU interface",
1228 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1229 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1230 		.matches = has_useable_gicv3_cpuif,
1231 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1232 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1233 		.sign = FTR_UNSIGNED,
1234 		.min_field_value = 1,
1235 	},
1236 #ifdef CONFIG_ARM64_PAN
1237 	{
1238 		.desc = "Privileged Access Never",
1239 		.capability = ARM64_HAS_PAN,
1240 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1241 		.matches = has_cpuid_feature,
1242 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1243 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1244 		.sign = FTR_UNSIGNED,
1245 		.min_field_value = 1,
1246 		.cpu_enable = cpu_enable_pan,
1247 	},
1248 #endif /* CONFIG_ARM64_PAN */
1249 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
1250 	{
1251 		.desc = "LSE atomic instructions",
1252 		.capability = ARM64_HAS_LSE_ATOMICS,
1253 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1254 		.matches = has_cpuid_feature,
1255 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1256 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1257 		.sign = FTR_UNSIGNED,
1258 		.min_field_value = 2,
1259 	},
1260 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
1261 	{
1262 		.desc = "Software prefetching using PRFM",
1263 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1264 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1265 		.matches = has_no_hw_prefetch,
1266 	},
1267 #ifdef CONFIG_ARM64_UAO
1268 	{
1269 		.desc = "User Access Override",
1270 		.capability = ARM64_HAS_UAO,
1271 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1272 		.matches = has_cpuid_feature,
1273 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1274 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
1275 		.min_field_value = 1,
1276 		/*
1277 		 * We rely on stop_machine() calling uao_thread_switch() to set
1278 		 * UAO immediately after patching.
1279 		 */
1280 	},
1281 #endif /* CONFIG_ARM64_UAO */
1282 #ifdef CONFIG_ARM64_PAN
1283 	{
1284 		.capability = ARM64_ALT_PAN_NOT_UAO,
1285 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1286 		.matches = cpufeature_pan_not_uao,
1287 	},
1288 #endif /* CONFIG_ARM64_PAN */
1289 #ifdef CONFIG_ARM64_VHE
1290 	{
1291 		.desc = "Virtualization Host Extensions",
1292 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1293 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1294 		.matches = runs_at_el2,
1295 		.cpu_enable = cpu_copy_el2regs,
1296 	},
1297 #endif	/* CONFIG_ARM64_VHE */
1298 	{
1299 		.desc = "32-bit EL0 Support",
1300 		.capability = ARM64_HAS_32BIT_EL0,
1301 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1302 		.matches = has_cpuid_feature,
1303 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1304 		.sign = FTR_UNSIGNED,
1305 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1306 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1307 	},
1308 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1309 	{
1310 		.desc = "Kernel page table isolation (KPTI)",
1311 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1312 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1313 		/*
1314 		 * The ID feature fields below are used to indicate that
1315 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1316 		 * more details.
1317 		 */
1318 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1319 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1320 		.min_field_value = 1,
1321 		.matches = unmap_kernel_at_el0,
1322 		.cpu_enable = kpti_install_ng_mappings,
1323 	},
1324 #endif
1325 	{
1326 		/* FP/SIMD is not implemented */
1327 		.capability = ARM64_HAS_NO_FPSIMD,
1328 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1329 		.min_field_value = 0,
1330 		.matches = has_no_fpsimd,
1331 	},
1332 #ifdef CONFIG_ARM64_PMEM
1333 	{
1334 		.desc = "Data cache clean to Point of Persistence",
1335 		.capability = ARM64_HAS_DCPOP,
1336 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1337 		.matches = has_cpuid_feature,
1338 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1339 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1340 		.min_field_value = 1,
1341 	},
1342 #endif
1343 #ifdef CONFIG_ARM64_SVE
1344 	{
1345 		.desc = "Scalable Vector Extension",
1346 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1347 		.capability = ARM64_SVE,
1348 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1349 		.sign = FTR_UNSIGNED,
1350 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
1351 		.min_field_value = ID_AA64PFR0_SVE,
1352 		.matches = has_cpuid_feature,
1353 		.cpu_enable = sve_kernel_enable,
1354 	},
1355 #endif /* CONFIG_ARM64_SVE */
1356 #ifdef CONFIG_ARM64_RAS_EXTN
1357 	{
1358 		.desc = "RAS Extension Support",
1359 		.capability = ARM64_HAS_RAS_EXTN,
1360 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1361 		.matches = has_cpuid_feature,
1362 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1363 		.sign = FTR_UNSIGNED,
1364 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
1365 		.min_field_value = ID_AA64PFR0_RAS_V1,
1366 		.cpu_enable = cpu_clear_disr,
1367 	},
1368 #endif /* CONFIG_ARM64_RAS_EXTN */
1369 	{
1370 		.desc = "Data cache clean to the PoU not required for I/D coherence",
1371 		.capability = ARM64_HAS_CACHE_IDC,
1372 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1373 		.matches = has_cache_idc,
1374 		.cpu_enable = cpu_emulate_effective_ctr,
1375 	},
1376 	{
1377 		.desc = "Instruction cache invalidation not required for I/D coherence",
1378 		.capability = ARM64_HAS_CACHE_DIC,
1379 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1380 		.matches = has_cache_dic,
1381 	},
1382 	{
1383 		.desc = "Stage-2 Force Write-Back",
1384 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1385 		.capability = ARM64_HAS_STAGE2_FWB,
1386 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1387 		.sign = FTR_UNSIGNED,
1388 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
1389 		.min_field_value = 1,
1390 		.matches = has_cpuid_feature,
1391 		.cpu_enable = cpu_has_fwb,
1392 	},
1393 #ifdef CONFIG_ARM64_HW_AFDBM
1394 	{
1395 		/*
1396 		 * Since we turn this on always, we don't want the user to
1397 		 * think that the feature is available when it may not be.
1398 		 * So hide the description.
1399 		 *
1400 		 * .desc = "Hardware pagetable Dirty Bit Management",
1401 		 *
1402 		 */
1403 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1404 		.capability = ARM64_HW_DBM,
1405 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1406 		.sign = FTR_UNSIGNED,
1407 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
1408 		.min_field_value = 2,
1409 		.matches = has_hw_dbm,
1410 		.cpu_enable = cpu_enable_hw_dbm,
1411 	},
1412 #endif
1413 	{
1414 		.desc = "CRC32 instructions",
1415 		.capability = ARM64_HAS_CRC32,
1416 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1417 		.matches = has_cpuid_feature,
1418 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1419 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
1420 		.min_field_value = 1,
1421 	},
1422 #ifdef CONFIG_ARM64_SSBD
1423 	{
1424 		.desc = "Speculative Store Bypassing Safe (SSBS)",
1425 		.capability = ARM64_SSBS,
1426 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1427 		.matches = has_cpuid_feature,
1428 		.sys_reg = SYS_ID_AA64PFR1_EL1,
1429 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
1430 		.sign = FTR_UNSIGNED,
1431 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
1432 		.cpu_enable = cpu_enable_ssbs,
1433 	},
1434 #endif
1435 #ifdef CONFIG_ARM64_CNP
1436 	{
1437 		.desc = "Common not Private translations",
1438 		.capability = ARM64_HAS_CNP,
1439 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1440 		.matches = has_useable_cnp,
1441 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1442 		.sign = FTR_UNSIGNED,
1443 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
1444 		.min_field_value = 1,
1445 		.cpu_enable = cpu_enable_cnp,
1446 	},
1447 #endif
1448 	{
1449 		.desc = "Speculation barrier (SB)",
1450 		.capability = ARM64_HAS_SB,
1451 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1452 		.matches = has_cpuid_feature,
1453 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1454 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
1455 		.sign = FTR_UNSIGNED,
1456 		.min_field_value = 1,
1457 	},
1458 #ifdef CONFIG_ARM64_PTR_AUTH
1459 	{
1460 		.desc = "Address authentication (architected algorithm)",
1461 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
1462 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1463 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1464 		.sign = FTR_UNSIGNED,
1465 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
1466 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
1467 		.matches = has_cpuid_feature,
1468 		.cpu_enable = cpu_enable_address_auth,
1469 	},
1470 	{
1471 		.desc = "Address authentication (IMP DEF algorithm)",
1472 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
1473 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1474 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1475 		.sign = FTR_UNSIGNED,
1476 		.field_pos = ID_AA64ISAR1_API_SHIFT,
1477 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
1478 		.matches = has_cpuid_feature,
1479 		.cpu_enable = cpu_enable_address_auth,
1480 	},
1481 	{
1482 		.desc = "Generic authentication (architected algorithm)",
1483 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
1484 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1485 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1486 		.sign = FTR_UNSIGNED,
1487 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
1488 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
1489 		.matches = has_cpuid_feature,
1490 	},
1491 	{
1492 		.desc = "Generic authentication (IMP DEF algorithm)",
1493 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
1494 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1495 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1496 		.sign = FTR_UNSIGNED,
1497 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
1498 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
1499 		.matches = has_cpuid_feature,
1500 	},
1501 #endif /* CONFIG_ARM64_PTR_AUTH */
1502 #ifdef CONFIG_ARM64_PSEUDO_NMI
1503 	{
1504 		/*
1505 		 * Depends on having GICv3
1506 		 */
1507 		.desc = "IRQ priority masking",
1508 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
1509 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1510 		.matches = can_use_gic_priorities,
1511 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1512 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1513 		.sign = FTR_UNSIGNED,
1514 		.min_field_value = 1,
1515 	},
1516 #endif
1517 	{},
1518 };
1519 
1520 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
1521 		.matches = has_cpuid_feature,					\
1522 		.sys_reg = reg,							\
1523 		.field_pos = field,						\
1524 		.sign = s,							\
1525 		.min_field_value = min_value,
1526 
1527 #define __HWCAP_CAP(name, cap_type, cap)					\
1528 		.desc = name,							\
1529 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
1530 		.hwcap_type = cap_type,						\
1531 		.hwcap = cap,							\
1532 
1533 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
1534 	{									\
1535 		__HWCAP_CAP(#cap, cap_type, cap)				\
1536 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
1537 	}
1538 
1539 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
1540 	{									\
1541 		__HWCAP_CAP(#cap, cap_type, cap)				\
1542 		.matches = cpucap_multi_entry_cap_matches,			\
1543 		.match_list = list,						\
1544 	}
1545 
1546 #ifdef CONFIG_ARM64_PTR_AUTH
1547 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
1548 	{
1549 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
1550 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
1551 	},
1552 	{
1553 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
1554 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
1555 	},
1556 	{},
1557 };
1558 
1559 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
1560 	{
1561 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
1562 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
1563 	},
1564 	{
1565 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
1566 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
1567 	},
1568 	{},
1569 };
1570 #endif
1571 
1572 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
1573 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_PMULL),
1574 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES),
1575 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1),
1576 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2),
1577 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_SHA512),
1578 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32),
1579 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
1580 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDRDM),
1581 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA3),
1582 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM3),
1583 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM4),
1584 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDDP),
1585 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDFHM),
1586 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_FLAGM),
1587 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
1588 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP),
1589 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
1590 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP),
1591 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_DIT),
1592 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_DCPOP),
1593 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_JSCVT),
1594 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_FCMA),
1595 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_LRCPC),
1596 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ILRCPC),
1597 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SB),
1598 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_USCAT),
1599 #ifdef CONFIG_ARM64_SVE
1600 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, HWCAP_SVE),
1601 #endif
1602 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, HWCAP_SSBS),
1603 #ifdef CONFIG_ARM64_PTR_AUTH
1604 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, HWCAP_PACA),
1605 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, HWCAP_PACG),
1606 #endif
1607 	{},
1608 };
1609 
1610 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
1611 #ifdef CONFIG_COMPAT
1612 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
1613 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
1614 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
1615 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
1616 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
1617 #endif
1618 	{},
1619 };
1620 
1621 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1622 {
1623 	switch (cap->hwcap_type) {
1624 	case CAP_HWCAP:
1625 		elf_hwcap |= cap->hwcap;
1626 		break;
1627 #ifdef CONFIG_COMPAT
1628 	case CAP_COMPAT_HWCAP:
1629 		compat_elf_hwcap |= (u32)cap->hwcap;
1630 		break;
1631 	case CAP_COMPAT_HWCAP2:
1632 		compat_elf_hwcap2 |= (u32)cap->hwcap;
1633 		break;
1634 #endif
1635 	default:
1636 		WARN_ON(1);
1637 		break;
1638 	}
1639 }
1640 
1641 /* Check if we have a particular HWCAP enabled */
1642 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1643 {
1644 	bool rc;
1645 
1646 	switch (cap->hwcap_type) {
1647 	case CAP_HWCAP:
1648 		rc = (elf_hwcap & cap->hwcap) != 0;
1649 		break;
1650 #ifdef CONFIG_COMPAT
1651 	case CAP_COMPAT_HWCAP:
1652 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
1653 		break;
1654 	case CAP_COMPAT_HWCAP2:
1655 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
1656 		break;
1657 #endif
1658 	default:
1659 		WARN_ON(1);
1660 		rc = false;
1661 	}
1662 
1663 	return rc;
1664 }
1665 
1666 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
1667 {
1668 	/* We support emulation of accesses to CPU ID feature registers */
1669 	elf_hwcap |= HWCAP_CPUID;
1670 	for (; hwcaps->matches; hwcaps++)
1671 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
1672 			cap_set_elf_hwcap(hwcaps);
1673 }
1674 
1675 static void update_cpu_capabilities(u16 scope_mask)
1676 {
1677 	int i;
1678 	const struct arm64_cpu_capabilities *caps;
1679 
1680 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1681 	for (i = 0; i < ARM64_NCAPS; i++) {
1682 		caps = cpu_hwcaps_ptrs[i];
1683 		if (!caps || !(caps->type & scope_mask) ||
1684 		    cpus_have_cap(caps->capability) ||
1685 		    !caps->matches(caps, cpucap_default_scope(caps)))
1686 			continue;
1687 
1688 		if (caps->desc)
1689 			pr_info("detected: %s\n", caps->desc);
1690 		cpus_set_cap(caps->capability);
1691 
1692 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
1693 			set_bit(caps->capability, boot_capabilities);
1694 	}
1695 }
1696 
1697 /*
1698  * Enable all the available capabilities on this CPU. The capabilities
1699  * with BOOT_CPU scope are handled separately and hence skipped here.
1700  */
1701 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
1702 {
1703 	int i;
1704 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
1705 
1706 	for_each_available_cap(i) {
1707 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
1708 
1709 		if (WARN_ON(!cap))
1710 			continue;
1711 
1712 		if (!(cap->type & non_boot_scope))
1713 			continue;
1714 
1715 		if (cap->cpu_enable)
1716 			cap->cpu_enable(cap);
1717 	}
1718 	return 0;
1719 }
1720 
1721 /*
1722  * Run through the enabled capabilities and enable() it on all active
1723  * CPUs
1724  */
1725 static void __init enable_cpu_capabilities(u16 scope_mask)
1726 {
1727 	int i;
1728 	const struct arm64_cpu_capabilities *caps;
1729 	bool boot_scope;
1730 
1731 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1732 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
1733 
1734 	for (i = 0; i < ARM64_NCAPS; i++) {
1735 		unsigned int num;
1736 
1737 		caps = cpu_hwcaps_ptrs[i];
1738 		if (!caps || !(caps->type & scope_mask))
1739 			continue;
1740 		num = caps->capability;
1741 		if (!cpus_have_cap(num))
1742 			continue;
1743 
1744 		/* Ensure cpus_have_const_cap(num) works */
1745 		static_branch_enable(&cpu_hwcap_keys[num]);
1746 
1747 		if (boot_scope && caps->cpu_enable)
1748 			/*
1749 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
1750 			 * before any secondary CPU boots. Thus, each secondary
1751 			 * will enable the capability as appropriate via
1752 			 * check_local_cpu_capabilities(). The only exception is
1753 			 * the boot CPU, for which the capability must be
1754 			 * enabled here. This approach avoids costly
1755 			 * stop_machine() calls for this case.
1756 			 */
1757 			caps->cpu_enable(caps);
1758 	}
1759 
1760 	/*
1761 	 * For all non-boot scope capabilities, use stop_machine()
1762 	 * as it schedules the work allowing us to modify PSTATE,
1763 	 * instead of on_each_cpu() which uses an IPI, giving us a
1764 	 * PSTATE that disappears when we return.
1765 	 */
1766 	if (!boot_scope)
1767 		stop_machine(cpu_enable_non_boot_scope_capabilities,
1768 			     NULL, cpu_online_mask);
1769 }
1770 
1771 /*
1772  * Run through the list of capabilities to check for conflicts.
1773  * If the system has already detected a capability, take necessary
1774  * action on this CPU.
1775  *
1776  * Returns "false" on conflicts.
1777  */
1778 static bool verify_local_cpu_caps(u16 scope_mask)
1779 {
1780 	int i;
1781 	bool cpu_has_cap, system_has_cap;
1782 	const struct arm64_cpu_capabilities *caps;
1783 
1784 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1785 
1786 	for (i = 0; i < ARM64_NCAPS; i++) {
1787 		caps = cpu_hwcaps_ptrs[i];
1788 		if (!caps || !(caps->type & scope_mask))
1789 			continue;
1790 
1791 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
1792 		system_has_cap = cpus_have_cap(caps->capability);
1793 
1794 		if (system_has_cap) {
1795 			/*
1796 			 * Check if the new CPU misses an advertised feature,
1797 			 * which is not safe to miss.
1798 			 */
1799 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
1800 				break;
1801 			/*
1802 			 * We have to issue cpu_enable() irrespective of
1803 			 * whether the CPU has it or not, as it is enabeld
1804 			 * system wide. It is upto the call back to take
1805 			 * appropriate action on this CPU.
1806 			 */
1807 			if (caps->cpu_enable)
1808 				caps->cpu_enable(caps);
1809 		} else {
1810 			/*
1811 			 * Check if the CPU has this capability if it isn't
1812 			 * safe to have when the system doesn't.
1813 			 */
1814 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
1815 				break;
1816 		}
1817 	}
1818 
1819 	if (i < ARM64_NCAPS) {
1820 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
1821 			smp_processor_id(), caps->capability,
1822 			caps->desc, system_has_cap, cpu_has_cap);
1823 		return false;
1824 	}
1825 
1826 	return true;
1827 }
1828 
1829 /*
1830  * Check for CPU features that are used in early boot
1831  * based on the Boot CPU value.
1832  */
1833 static void check_early_cpu_features(void)
1834 {
1835 	verify_cpu_asid_bits();
1836 	/*
1837 	 * Early features are used by the kernel already. If there
1838 	 * is a conflict, we cannot proceed further.
1839 	 */
1840 	if (!verify_local_cpu_caps(SCOPE_BOOT_CPU))
1841 		cpu_panic_kernel();
1842 }
1843 
1844 static void
1845 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
1846 {
1847 
1848 	for (; caps->matches; caps++)
1849 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
1850 			pr_crit("CPU%d: missing HWCAP: %s\n",
1851 					smp_processor_id(), caps->desc);
1852 			cpu_die_early();
1853 		}
1854 }
1855 
1856 static void verify_sve_features(void)
1857 {
1858 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
1859 	u64 zcr = read_zcr_features();
1860 
1861 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
1862 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
1863 
1864 	if (len < safe_len || sve_verify_vq_map()) {
1865 		pr_crit("CPU%d: SVE: required vector length(s) missing\n",
1866 			smp_processor_id());
1867 		cpu_die_early();
1868 	}
1869 
1870 	/* Add checks on other ZCR bits here if necessary */
1871 }
1872 
1873 
1874 /*
1875  * Run through the enabled system capabilities and enable() it on this CPU.
1876  * The capabilities were decided based on the available CPUs at the boot time.
1877  * Any new CPU should match the system wide status of the capability. If the
1878  * new CPU doesn't have a capability which the system now has enabled, we
1879  * cannot do anything to fix it up and could cause unexpected failures. So
1880  * we park the CPU.
1881  */
1882 static void verify_local_cpu_capabilities(void)
1883 {
1884 	/*
1885 	 * The capabilities with SCOPE_BOOT_CPU are checked from
1886 	 * check_early_cpu_features(), as they need to be verified
1887 	 * on all secondary CPUs.
1888 	 */
1889 	if (!verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU))
1890 		cpu_die_early();
1891 
1892 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
1893 
1894 	if (system_supports_32bit_el0())
1895 		verify_local_elf_hwcaps(compat_elf_hwcaps);
1896 
1897 	if (system_supports_sve())
1898 		verify_sve_features();
1899 }
1900 
1901 void check_local_cpu_capabilities(void)
1902 {
1903 	/*
1904 	 * All secondary CPUs should conform to the early CPU features
1905 	 * in use by the kernel based on boot CPU.
1906 	 */
1907 	check_early_cpu_features();
1908 
1909 	/*
1910 	 * If we haven't finalised the system capabilities, this CPU gets
1911 	 * a chance to update the errata work arounds and local features.
1912 	 * Otherwise, this CPU should verify that it has all the system
1913 	 * advertised capabilities.
1914 	 */
1915 	if (!sys_caps_initialised)
1916 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
1917 	else
1918 		verify_local_cpu_capabilities();
1919 }
1920 
1921 static void __init setup_boot_cpu_capabilities(void)
1922 {
1923 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
1924 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
1925 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
1926 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
1927 }
1928 
1929 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
1930 EXPORT_SYMBOL(arm64_const_caps_ready);
1931 
1932 static void __init mark_const_caps_ready(void)
1933 {
1934 	static_branch_enable(&arm64_const_caps_ready);
1935 }
1936 
1937 bool this_cpu_has_cap(unsigned int n)
1938 {
1939 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
1940 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
1941 
1942 		if (cap)
1943 			return cap->matches(cap, SCOPE_LOCAL_CPU);
1944 	}
1945 
1946 	return false;
1947 }
1948 
1949 static void __init setup_system_capabilities(void)
1950 {
1951 	/*
1952 	 * We have finalised the system-wide safe feature
1953 	 * registers, finalise the capabilities that depend
1954 	 * on it. Also enable all the available capabilities,
1955 	 * that are not enabled already.
1956 	 */
1957 	update_cpu_capabilities(SCOPE_SYSTEM);
1958 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
1959 }
1960 
1961 void __init setup_cpu_features(void)
1962 {
1963 	u32 cwg;
1964 
1965 	setup_system_capabilities();
1966 	mark_const_caps_ready();
1967 	setup_elf_hwcaps(arm64_elf_hwcaps);
1968 
1969 	if (system_supports_32bit_el0())
1970 		setup_elf_hwcaps(compat_elf_hwcaps);
1971 
1972 	if (system_uses_ttbr0_pan())
1973 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
1974 
1975 	sve_setup();
1976 	minsigstksz_setup();
1977 
1978 	/* Advertise that we have computed the system capabilities */
1979 	set_sys_caps_initialised();
1980 
1981 	/*
1982 	 * Check for sane CTR_EL0.CWG value.
1983 	 */
1984 	cwg = cache_type_cwg();
1985 	if (!cwg)
1986 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
1987 			ARCH_DMA_MINALIGN);
1988 }
1989 
1990 static bool __maybe_unused
1991 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
1992 {
1993 	return (cpus_have_const_cap(ARM64_HAS_PAN) && !cpus_have_const_cap(ARM64_HAS_UAO));
1994 }
1995 
1996 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
1997 {
1998 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
1999 }
2000 
2001 /*
2002  * We emulate only the following system register space.
2003  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2004  * See Table C5-6 System instruction encodings for System register accesses,
2005  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2006  */
2007 static inline bool __attribute_const__ is_emulated(u32 id)
2008 {
2009 	return (sys_reg_Op0(id) == 0x3 &&
2010 		sys_reg_CRn(id) == 0x0 &&
2011 		sys_reg_Op1(id) == 0x0 &&
2012 		(sys_reg_CRm(id) == 0 ||
2013 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2014 }
2015 
2016 /*
2017  * With CRm == 0, reg should be one of :
2018  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2019  */
2020 static inline int emulate_id_reg(u32 id, u64 *valp)
2021 {
2022 	switch (id) {
2023 	case SYS_MIDR_EL1:
2024 		*valp = read_cpuid_id();
2025 		break;
2026 	case SYS_MPIDR_EL1:
2027 		*valp = SYS_MPIDR_SAFE_VAL;
2028 		break;
2029 	case SYS_REVIDR_EL1:
2030 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2031 		*valp = 0;
2032 		break;
2033 	default:
2034 		return -EINVAL;
2035 	}
2036 
2037 	return 0;
2038 }
2039 
2040 static int emulate_sys_reg(u32 id, u64 *valp)
2041 {
2042 	struct arm64_ftr_reg *regp;
2043 
2044 	if (!is_emulated(id))
2045 		return -EINVAL;
2046 
2047 	if (sys_reg_CRm(id) == 0)
2048 		return emulate_id_reg(id, valp);
2049 
2050 	regp = get_arm64_ftr_reg(id);
2051 	if (regp)
2052 		*valp = arm64_ftr_reg_user_value(regp);
2053 	else
2054 		/*
2055 		 * The untracked registers are either IMPLEMENTATION DEFINED
2056 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2057 		 */
2058 		*valp = 0;
2059 	return 0;
2060 }
2061 
2062 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2063 {
2064 	int rc;
2065 	u64 val;
2066 
2067 	rc = emulate_sys_reg(sys_reg, &val);
2068 	if (!rc) {
2069 		pt_regs_write_reg(regs, rt, val);
2070 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2071 	}
2072 	return rc;
2073 }
2074 
2075 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2076 {
2077 	u32 sys_reg, rt;
2078 
2079 	/*
2080 	 * sys_reg values are defined as used in mrs/msr instruction.
2081 	 * shift the imm value to get the encoding.
2082 	 */
2083 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2084 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2085 	return do_emulate_mrs(regs, sys_reg, rt);
2086 }
2087 
2088 static struct undef_hook mrs_hook = {
2089 	.instr_mask = 0xfff00000,
2090 	.instr_val  = 0xd5300000,
2091 	.pstate_mask = PSR_AA32_MODE_MASK,
2092 	.pstate_val = PSR_MODE_EL0t,
2093 	.fn = emulate_mrs,
2094 };
2095 
2096 static int __init enable_mrs_emulation(void)
2097 {
2098 	register_undef_hook(&mrs_hook);
2099 	return 0;
2100 }
2101 
2102 core_initcall(enable_mrs_emulation);
2103