xref: /linux/arch/arm64/kernel/cpufeature.c (revision 32786fdc9506aeba98278c1844d4bfb766863832)
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/sort.h>
24 #include <linux/stop_machine.h>
25 #include <linux/types.h>
26 #include <asm/cpu.h>
27 #include <asm/cpufeature.h>
28 #include <asm/cpu_ops.h>
29 #include <asm/mmu_context.h>
30 #include <asm/processor.h>
31 #include <asm/sysreg.h>
32 #include <asm/virt.h>
33 
34 unsigned long elf_hwcap __read_mostly;
35 EXPORT_SYMBOL_GPL(elf_hwcap);
36 
37 #ifdef CONFIG_COMPAT
38 #define COMPAT_ELF_HWCAP_DEFAULT	\
39 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
40 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
41 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
42 				 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
43 				 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
44 				 COMPAT_HWCAP_LPAE)
45 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
46 unsigned int compat_elf_hwcap2 __read_mostly;
47 #endif
48 
49 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
50 EXPORT_SYMBOL(cpu_hwcaps);
51 
52 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
53 EXPORT_SYMBOL(cpu_hwcap_keys);
54 
55 #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
56 	{						\
57 		.sign = SIGNED,				\
58 		.strict = STRICT,			\
59 		.type = TYPE,				\
60 		.shift = SHIFT,				\
61 		.width = WIDTH,				\
62 		.safe_val = SAFE_VAL,			\
63 	}
64 
65 /* Define a feature with unsigned values */
66 #define ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
67 	__ARM64_FTR_BITS(FTR_UNSIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
68 
69 /* Define a feature with a signed value */
70 #define S_ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
71 	__ARM64_FTR_BITS(FTR_SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
72 
73 #define ARM64_FTR_END					\
74 	{						\
75 		.width = 0,				\
76 	}
77 
78 /* meta feature for alternatives */
79 static bool __maybe_unused
80 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
81 
82 
83 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
84 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
85 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
86 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),
87 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
88 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
89 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
90 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
91 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
92 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* RAZ */
93 	ARM64_FTR_END,
94 };
95 
96 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
97 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
98 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0),
99 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_GIC_SHIFT, 4, 0),
100 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
101 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
102 	/* Linux doesn't care about the EL3 */
103 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64PFR0_EL3_SHIFT, 4, 0),
104 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL2_SHIFT, 4, 0),
105 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
106 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
107 	ARM64_FTR_END,
108 };
109 
110 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
111 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
112 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
113 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
114 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
115 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
116 	/* Linux shouldn't care about secure memory */
117 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
118 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
119 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
120 	/*
121 	 * Differing PARange is fine as long as all peripherals and memory are mapped
122 	 * within the minimum PARange of all CPUs
123 	 */
124 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
125 	ARM64_FTR_END,
126 };
127 
128 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
129 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
130 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
131 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
132 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
133 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
134 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
135 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
136 	ARM64_FTR_END,
137 };
138 
139 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
140 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
141 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
142 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
143 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
144 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
145 	ARM64_FTR_END,
146 };
147 
148 static const struct arm64_ftr_bits ftr_ctr[] = {
149 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1),	/* RAO */
150 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 3, 0),
151 	ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0),	/* CWG */
152 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* ERG */
153 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1),	/* DminLine */
154 	/*
155 	 * Linux can handle differing I-cache policies. Userspace JITs will
156 	 * make use of *minLine.
157 	 * If we have differing I-cache policies, report it as the weakest - AIVIVT.
158 	 */
159 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_AIVIVT),	/* L1Ip */
160 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 10, 0),	/* RAZ */
161 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* IminLine */
162 	ARM64_FTR_END,
163 };
164 
165 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
166 	.name		= "SYS_CTR_EL0",
167 	.ftr_bits	= ftr_ctr
168 };
169 
170 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
171 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0xf),	/* InnerShr */
172 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),	/* FCSE */
173 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* AuxReg */
174 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 4, 0),	/* TCM */
175 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* ShareLvl */
176 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0xf),	/* OuterShr */
177 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),	/* PMSA */
178 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* VMSA */
179 	ARM64_FTR_END,
180 };
181 
182 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
183 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
184 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
187 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
188 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
189 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
190 	ARM64_FTR_END,
191 };
192 
193 static const struct arm64_ftr_bits ftr_mvfr2[] = {
194 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
195 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* FPMisc */
196 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* SIMDMisc */
197 	ARM64_FTR_END,
198 };
199 
200 static const struct arm64_ftr_bits ftr_dczid[] = {
201 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 5, 27, 0),	/* RAZ */
202 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 1, 1),		/* DZP */
203 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* BS */
204 	ARM64_FTR_END,
205 };
206 
207 
208 static const struct arm64_ftr_bits ftr_id_isar5[] = {
209 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_RDM_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 20, 4, 0),	/* RAZ */
211 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_CRC32_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA2_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA1_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_AES_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SEVL_SHIFT, 4, 0),
216 	ARM64_FTR_END,
217 };
218 
219 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
220 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
221 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* ac2 */
222 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* RAZ */
223 	ARM64_FTR_END,
224 };
225 
226 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
227 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 16, 0),	/* RAZ */
228 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* State3 */
229 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0),		/* State2 */
230 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* State1 */
231 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* State0 */
232 	ARM64_FTR_END,
233 };
234 
235 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
236 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
237 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf),	/* PerfMon */
238 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
239 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
240 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
241 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
242 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
243 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
244 	ARM64_FTR_END,
245 };
246 
247 /*
248  * Common ftr bits for a 32bit register with all hidden, strict
249  * attributes, with 4bit feature fields and a default safe value of
250  * 0. Covers the following 32bit registers:
251  * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
252  */
253 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
254 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
255 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
256 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
257 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
258 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
259 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
260 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
261 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
262 	ARM64_FTR_END,
263 };
264 
265 static const struct arm64_ftr_bits ftr_generic[] = {
266 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
267 	ARM64_FTR_END,
268 };
269 
270 static const struct arm64_ftr_bits ftr_generic32[] = {
271 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 32, 0),
272 	ARM64_FTR_END,
273 };
274 
275 static const struct arm64_ftr_bits ftr_aa64raz[] = {
276 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
277 	ARM64_FTR_END,
278 };
279 
280 #define ARM64_FTR_REG(id, table) {		\
281 	.sys_id = id,				\
282 	.reg = 	&(struct arm64_ftr_reg){	\
283 		.name = #id,			\
284 		.ftr_bits = &((table)[0]),	\
285 	}}
286 
287 static const struct __ftr_reg_entry {
288 	u32			sys_id;
289 	struct arm64_ftr_reg 	*reg;
290 } arm64_ftr_regs[] = {
291 
292 	/* Op1 = 0, CRn = 0, CRm = 1 */
293 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
294 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
295 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
296 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
297 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
298 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
299 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
300 
301 	/* Op1 = 0, CRn = 0, CRm = 2 */
302 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
303 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
304 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
305 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
306 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
307 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
308 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
309 
310 	/* Op1 = 0, CRn = 0, CRm = 3 */
311 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
312 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
313 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
314 
315 	/* Op1 = 0, CRn = 0, CRm = 4 */
316 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
317 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_aa64raz),
318 
319 	/* Op1 = 0, CRn = 0, CRm = 5 */
320 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
321 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_generic),
322 
323 	/* Op1 = 0, CRn = 0, CRm = 6 */
324 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
325 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz),
326 
327 	/* Op1 = 0, CRn = 0, CRm = 7 */
328 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
329 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
330 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
331 
332 	/* Op1 = 3, CRn = 0, CRm = 0 */
333 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
334 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
335 
336 	/* Op1 = 3, CRn = 14, CRm = 0 */
337 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_generic32),
338 };
339 
340 static int search_cmp_ftr_reg(const void *id, const void *regp)
341 {
342 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
343 }
344 
345 /*
346  * get_arm64_ftr_reg - Lookup a feature register entry using its
347  * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
348  * ascending order of sys_id , we use binary search to find a matching
349  * entry.
350  *
351  * returns - Upon success,  matching ftr_reg entry for id.
352  *         - NULL on failure. It is upto the caller to decide
353  *	     the impact of a failure.
354  */
355 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
356 {
357 	const struct __ftr_reg_entry *ret;
358 
359 	ret = bsearch((const void *)(unsigned long)sys_id,
360 			arm64_ftr_regs,
361 			ARRAY_SIZE(arm64_ftr_regs),
362 			sizeof(arm64_ftr_regs[0]),
363 			search_cmp_ftr_reg);
364 	if (ret)
365 		return ret->reg;
366 	return NULL;
367 }
368 
369 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
370 			       s64 ftr_val)
371 {
372 	u64 mask = arm64_ftr_mask(ftrp);
373 
374 	reg &= ~mask;
375 	reg |= (ftr_val << ftrp->shift) & mask;
376 	return reg;
377 }
378 
379 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
380 				s64 cur)
381 {
382 	s64 ret = 0;
383 
384 	switch (ftrp->type) {
385 	case FTR_EXACT:
386 		ret = ftrp->safe_val;
387 		break;
388 	case FTR_LOWER_SAFE:
389 		ret = new < cur ? new : cur;
390 		break;
391 	case FTR_HIGHER_SAFE:
392 		ret = new > cur ? new : cur;
393 		break;
394 	default:
395 		BUG();
396 	}
397 
398 	return ret;
399 }
400 
401 static void __init sort_ftr_regs(void)
402 {
403 	int i;
404 
405 	/* Check that the array is sorted so that we can do the binary search */
406 	for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++)
407 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
408 }
409 
410 /*
411  * Initialise the CPU feature register from Boot CPU values.
412  * Also initiliases the strict_mask for the register.
413  */
414 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
415 {
416 	u64 val = 0;
417 	u64 strict_mask = ~0x0ULL;
418 	const struct arm64_ftr_bits *ftrp;
419 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
420 
421 	BUG_ON(!reg);
422 
423 	for (ftrp  = reg->ftr_bits; ftrp->width; ftrp++) {
424 		s64 ftr_new = arm64_ftr_value(ftrp, new);
425 
426 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
427 		if (!ftrp->strict)
428 			strict_mask &= ~arm64_ftr_mask(ftrp);
429 	}
430 	reg->sys_val = val;
431 	reg->strict_mask = strict_mask;
432 }
433 
434 void __init init_cpu_features(struct cpuinfo_arm64 *info)
435 {
436 	/* Before we start using the tables, make sure it is sorted */
437 	sort_ftr_regs();
438 
439 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
440 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
441 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
442 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
443 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
444 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
445 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
446 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
447 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
448 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
449 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
450 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
451 
452 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
453 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
454 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
455 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
456 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
457 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
458 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
459 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
460 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
461 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
462 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
463 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
464 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
465 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
466 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
467 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
468 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
469 	}
470 
471 }
472 
473 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
474 {
475 	const struct arm64_ftr_bits *ftrp;
476 
477 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
478 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
479 		s64 ftr_new = arm64_ftr_value(ftrp, new);
480 
481 		if (ftr_cur == ftr_new)
482 			continue;
483 		/* Find a safe value */
484 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
485 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
486 	}
487 
488 }
489 
490 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
491 {
492 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
493 
494 	BUG_ON(!regp);
495 	update_cpu_ftr_reg(regp, val);
496 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
497 		return 0;
498 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
499 			regp->name, boot, cpu, val);
500 	return 1;
501 }
502 
503 /*
504  * Update system wide CPU feature registers with the values from a
505  * non-boot CPU. Also performs SANITY checks to make sure that there
506  * aren't any insane variations from that of the boot CPU.
507  */
508 void update_cpu_features(int cpu,
509 			 struct cpuinfo_arm64 *info,
510 			 struct cpuinfo_arm64 *boot)
511 {
512 	int taint = 0;
513 
514 	/*
515 	 * The kernel can handle differing I-cache policies, but otherwise
516 	 * caches should look identical. Userspace JITs will make use of
517 	 * *minLine.
518 	 */
519 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
520 				      info->reg_ctr, boot->reg_ctr);
521 
522 	/*
523 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
524 	 * could result in too much or too little memory being zeroed if a
525 	 * process is preempted and migrated between CPUs.
526 	 */
527 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
528 				      info->reg_dczid, boot->reg_dczid);
529 
530 	/* If different, timekeeping will be broken (especially with KVM) */
531 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
532 				      info->reg_cntfrq, boot->reg_cntfrq);
533 
534 	/*
535 	 * The kernel uses self-hosted debug features and expects CPUs to
536 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
537 	 * and BRPs to be identical.
538 	 * ID_AA64DFR1 is currently RES0.
539 	 */
540 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
541 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
542 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
543 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
544 	/*
545 	 * Even in big.LITTLE, processors should be identical instruction-set
546 	 * wise.
547 	 */
548 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
549 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
550 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
551 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
552 
553 	/*
554 	 * Differing PARange support is fine as long as all peripherals and
555 	 * memory are mapped within the minimum PARange of all CPUs.
556 	 * Linux should not care about secure memory.
557 	 */
558 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
559 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
560 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
561 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
562 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
563 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
564 
565 	/*
566 	 * EL3 is not our concern.
567 	 * ID_AA64PFR1 is currently RES0.
568 	 */
569 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
570 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
571 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
572 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
573 
574 	/*
575 	 * If we have AArch32, we care about 32-bit features for compat.
576 	 * If the system doesn't support AArch32, don't update them.
577 	 */
578 	if (id_aa64pfr0_32bit_el0(read_system_reg(SYS_ID_AA64PFR0_EL1)) &&
579 		id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
580 
581 		taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
582 					info->reg_id_dfr0, boot->reg_id_dfr0);
583 		taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
584 					info->reg_id_isar0, boot->reg_id_isar0);
585 		taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
586 					info->reg_id_isar1, boot->reg_id_isar1);
587 		taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
588 					info->reg_id_isar2, boot->reg_id_isar2);
589 		taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
590 					info->reg_id_isar3, boot->reg_id_isar3);
591 		taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
592 					info->reg_id_isar4, boot->reg_id_isar4);
593 		taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
594 					info->reg_id_isar5, boot->reg_id_isar5);
595 
596 		/*
597 		 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
598 		 * ACTLR formats could differ across CPUs and therefore would have to
599 		 * be trapped for virtualization anyway.
600 		 */
601 		taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
602 					info->reg_id_mmfr0, boot->reg_id_mmfr0);
603 		taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
604 					info->reg_id_mmfr1, boot->reg_id_mmfr1);
605 		taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
606 					info->reg_id_mmfr2, boot->reg_id_mmfr2);
607 		taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
608 					info->reg_id_mmfr3, boot->reg_id_mmfr3);
609 		taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
610 					info->reg_id_pfr0, boot->reg_id_pfr0);
611 		taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
612 					info->reg_id_pfr1, boot->reg_id_pfr1);
613 		taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
614 					info->reg_mvfr0, boot->reg_mvfr0);
615 		taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
616 					info->reg_mvfr1, boot->reg_mvfr1);
617 		taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
618 					info->reg_mvfr2, boot->reg_mvfr2);
619 	}
620 
621 	/*
622 	 * Mismatched CPU features are a recipe for disaster. Don't even
623 	 * pretend to support them.
624 	 */
625 	WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC,
626 			"Unsupported CPU feature variation.\n");
627 }
628 
629 u64 read_system_reg(u32 id)
630 {
631 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
632 
633 	/* We shouldn't get a request for an unsupported register */
634 	BUG_ON(!regp);
635 	return regp->sys_val;
636 }
637 
638 /*
639  * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated.
640  * Read the system register on the current CPU
641  */
642 static u64 __raw_read_system_reg(u32 sys_id)
643 {
644 	switch (sys_id) {
645 	case SYS_ID_PFR0_EL1:		return read_cpuid(ID_PFR0_EL1);
646 	case SYS_ID_PFR1_EL1:		return read_cpuid(ID_PFR1_EL1);
647 	case SYS_ID_DFR0_EL1:		return read_cpuid(ID_DFR0_EL1);
648 	case SYS_ID_MMFR0_EL1:		return read_cpuid(ID_MMFR0_EL1);
649 	case SYS_ID_MMFR1_EL1:		return read_cpuid(ID_MMFR1_EL1);
650 	case SYS_ID_MMFR2_EL1:		return read_cpuid(ID_MMFR2_EL1);
651 	case SYS_ID_MMFR3_EL1:		return read_cpuid(ID_MMFR3_EL1);
652 	case SYS_ID_ISAR0_EL1:		return read_cpuid(ID_ISAR0_EL1);
653 	case SYS_ID_ISAR1_EL1:		return read_cpuid(ID_ISAR1_EL1);
654 	case SYS_ID_ISAR2_EL1:		return read_cpuid(ID_ISAR2_EL1);
655 	case SYS_ID_ISAR3_EL1:		return read_cpuid(ID_ISAR3_EL1);
656 	case SYS_ID_ISAR4_EL1:		return read_cpuid(ID_ISAR4_EL1);
657 	case SYS_ID_ISAR5_EL1:		return read_cpuid(ID_ISAR4_EL1);
658 	case SYS_MVFR0_EL1:		return read_cpuid(MVFR0_EL1);
659 	case SYS_MVFR1_EL1:		return read_cpuid(MVFR1_EL1);
660 	case SYS_MVFR2_EL1:		return read_cpuid(MVFR2_EL1);
661 
662 	case SYS_ID_AA64PFR0_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
663 	case SYS_ID_AA64PFR1_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
664 	case SYS_ID_AA64DFR0_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
665 	case SYS_ID_AA64DFR1_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
666 	case SYS_ID_AA64MMFR0_EL1:	return read_cpuid(ID_AA64MMFR0_EL1);
667 	case SYS_ID_AA64MMFR1_EL1:	return read_cpuid(ID_AA64MMFR1_EL1);
668 	case SYS_ID_AA64MMFR2_EL1:	return read_cpuid(ID_AA64MMFR2_EL1);
669 	case SYS_ID_AA64ISAR0_EL1:	return read_cpuid(ID_AA64ISAR0_EL1);
670 	case SYS_ID_AA64ISAR1_EL1:	return read_cpuid(ID_AA64ISAR1_EL1);
671 
672 	case SYS_CNTFRQ_EL0:		return read_cpuid(CNTFRQ_EL0);
673 	case SYS_CTR_EL0:		return read_cpuid(CTR_EL0);
674 	case SYS_DCZID_EL0:		return read_cpuid(DCZID_EL0);
675 	default:
676 		BUG();
677 		return 0;
678 	}
679 }
680 
681 #include <linux/irqchip/arm-gic-v3.h>
682 
683 static bool
684 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
685 {
686 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
687 
688 	return val >= entry->min_field_value;
689 }
690 
691 static bool
692 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
693 {
694 	u64 val;
695 
696 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
697 	if (scope == SCOPE_SYSTEM)
698 		val = read_system_reg(entry->sys_reg);
699 	else
700 		val = __raw_read_system_reg(entry->sys_reg);
701 
702 	return feature_matches(val, entry);
703 }
704 
705 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
706 {
707 	bool has_sre;
708 
709 	if (!has_cpuid_feature(entry, scope))
710 		return false;
711 
712 	has_sre = gic_enable_sre();
713 	if (!has_sre)
714 		pr_warn_once("%s present but disabled by higher exception level\n",
715 			     entry->desc);
716 
717 	return has_sre;
718 }
719 
720 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
721 {
722 	u32 midr = read_cpuid_id();
723 	u32 rv_min, rv_max;
724 
725 	/* Cavium ThunderX pass 1.x and 2.x */
726 	rv_min = 0;
727 	rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK;
728 
729 	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max);
730 }
731 
732 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
733 {
734 	return is_kernel_in_hyp_mode();
735 }
736 
737 static bool hyp_offset_low(const struct arm64_cpu_capabilities *entry,
738 			   int __unused)
739 {
740 	phys_addr_t idmap_addr = virt_to_phys(__hyp_idmap_text_start);
741 
742 	/*
743 	 * Activate the lower HYP offset only if:
744 	 * - the idmap doesn't clash with it,
745 	 * - the kernel is not running at EL2.
746 	 */
747 	return idmap_addr > GENMASK(VA_BITS - 2, 0) && !is_kernel_in_hyp_mode();
748 }
749 
750 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
751 {
752 	u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1);
753 
754 	return cpuid_feature_extract_signed_field(pfr0,
755 					ID_AA64PFR0_FP_SHIFT) < 0;
756 }
757 
758 static const struct arm64_cpu_capabilities arm64_features[] = {
759 	{
760 		.desc = "GIC system register CPU interface",
761 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
762 		.def_scope = SCOPE_SYSTEM,
763 		.matches = has_useable_gicv3_cpuif,
764 		.sys_reg = SYS_ID_AA64PFR0_EL1,
765 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
766 		.sign = FTR_UNSIGNED,
767 		.min_field_value = 1,
768 	},
769 #ifdef CONFIG_ARM64_PAN
770 	{
771 		.desc = "Privileged Access Never",
772 		.capability = ARM64_HAS_PAN,
773 		.def_scope = SCOPE_SYSTEM,
774 		.matches = has_cpuid_feature,
775 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
776 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
777 		.sign = FTR_UNSIGNED,
778 		.min_field_value = 1,
779 		.enable = cpu_enable_pan,
780 	},
781 #endif /* CONFIG_ARM64_PAN */
782 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
783 	{
784 		.desc = "LSE atomic instructions",
785 		.capability = ARM64_HAS_LSE_ATOMICS,
786 		.def_scope = SCOPE_SYSTEM,
787 		.matches = has_cpuid_feature,
788 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
789 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
790 		.sign = FTR_UNSIGNED,
791 		.min_field_value = 2,
792 	},
793 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
794 	{
795 		.desc = "Software prefetching using PRFM",
796 		.capability = ARM64_HAS_NO_HW_PREFETCH,
797 		.def_scope = SCOPE_SYSTEM,
798 		.matches = has_no_hw_prefetch,
799 	},
800 #ifdef CONFIG_ARM64_UAO
801 	{
802 		.desc = "User Access Override",
803 		.capability = ARM64_HAS_UAO,
804 		.def_scope = SCOPE_SYSTEM,
805 		.matches = has_cpuid_feature,
806 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
807 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
808 		.min_field_value = 1,
809 		.enable = cpu_enable_uao,
810 	},
811 #endif /* CONFIG_ARM64_UAO */
812 #ifdef CONFIG_ARM64_PAN
813 	{
814 		.capability = ARM64_ALT_PAN_NOT_UAO,
815 		.def_scope = SCOPE_SYSTEM,
816 		.matches = cpufeature_pan_not_uao,
817 	},
818 #endif /* CONFIG_ARM64_PAN */
819 	{
820 		.desc = "Virtualization Host Extensions",
821 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
822 		.def_scope = SCOPE_SYSTEM,
823 		.matches = runs_at_el2,
824 	},
825 	{
826 		.desc = "32-bit EL0 Support",
827 		.capability = ARM64_HAS_32BIT_EL0,
828 		.def_scope = SCOPE_SYSTEM,
829 		.matches = has_cpuid_feature,
830 		.sys_reg = SYS_ID_AA64PFR0_EL1,
831 		.sign = FTR_UNSIGNED,
832 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
833 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
834 	},
835 	{
836 		.desc = "Reduced HYP mapping offset",
837 		.capability = ARM64_HYP_OFFSET_LOW,
838 		.def_scope = SCOPE_SYSTEM,
839 		.matches = hyp_offset_low,
840 	},
841 	{
842 		/* FP/SIMD is not implemented */
843 		.capability = ARM64_HAS_NO_FPSIMD,
844 		.def_scope = SCOPE_SYSTEM,
845 		.min_field_value = 0,
846 		.matches = has_no_fpsimd,
847 	},
848 	{},
849 };
850 
851 #define HWCAP_CAP(reg, field, s, min_value, type, cap)	\
852 	{							\
853 		.desc = #cap,					\
854 		.def_scope = SCOPE_SYSTEM,			\
855 		.matches = has_cpuid_feature,			\
856 		.sys_reg = reg,					\
857 		.field_pos = field,				\
858 		.sign = s,					\
859 		.min_field_value = min_value,			\
860 		.hwcap_type = type,				\
861 		.hwcap = cap,					\
862 	}
863 
864 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
865 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_PMULL),
866 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES),
867 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1),
868 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2),
869 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32),
870 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
871 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
872 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP),
873 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
874 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP),
875 	{},
876 };
877 
878 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
879 #ifdef CONFIG_COMPAT
880 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
881 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
882 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
883 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
884 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
885 #endif
886 	{},
887 };
888 
889 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
890 {
891 	switch (cap->hwcap_type) {
892 	case CAP_HWCAP:
893 		elf_hwcap |= cap->hwcap;
894 		break;
895 #ifdef CONFIG_COMPAT
896 	case CAP_COMPAT_HWCAP:
897 		compat_elf_hwcap |= (u32)cap->hwcap;
898 		break;
899 	case CAP_COMPAT_HWCAP2:
900 		compat_elf_hwcap2 |= (u32)cap->hwcap;
901 		break;
902 #endif
903 	default:
904 		WARN_ON(1);
905 		break;
906 	}
907 }
908 
909 /* Check if we have a particular HWCAP enabled */
910 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
911 {
912 	bool rc;
913 
914 	switch (cap->hwcap_type) {
915 	case CAP_HWCAP:
916 		rc = (elf_hwcap & cap->hwcap) != 0;
917 		break;
918 #ifdef CONFIG_COMPAT
919 	case CAP_COMPAT_HWCAP:
920 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
921 		break;
922 	case CAP_COMPAT_HWCAP2:
923 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
924 		break;
925 #endif
926 	default:
927 		WARN_ON(1);
928 		rc = false;
929 	}
930 
931 	return rc;
932 }
933 
934 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
935 {
936 	for (; hwcaps->matches; hwcaps++)
937 		if (hwcaps->matches(hwcaps, hwcaps->def_scope))
938 			cap_set_elf_hwcap(hwcaps);
939 }
940 
941 void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
942 			    const char *info)
943 {
944 	for (; caps->matches; caps++) {
945 		if (!caps->matches(caps, caps->def_scope))
946 			continue;
947 
948 		if (!cpus_have_cap(caps->capability) && caps->desc)
949 			pr_info("%s %s\n", info, caps->desc);
950 		cpus_set_cap(caps->capability);
951 	}
952 }
953 
954 /*
955  * Run through the enabled capabilities and enable() it on all active
956  * CPUs
957  */
958 void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
959 {
960 	for (; caps->matches; caps++)
961 		if (caps->enable && cpus_have_cap(caps->capability))
962 			/*
963 			 * Use stop_machine() as it schedules the work allowing
964 			 * us to modify PSTATE, instead of on_each_cpu() which
965 			 * uses an IPI, giving us a PSTATE that disappears when
966 			 * we return.
967 			 */
968 			stop_machine(caps->enable, NULL, cpu_online_mask);
969 }
970 
971 /*
972  * Flag to indicate if we have computed the system wide
973  * capabilities based on the boot time active CPUs. This
974  * will be used to determine if a new booting CPU should
975  * go through the verification process to make sure that it
976  * supports the system capabilities, without using a hotplug
977  * notifier.
978  */
979 static bool sys_caps_initialised;
980 
981 static inline void set_sys_caps_initialised(void)
982 {
983 	sys_caps_initialised = true;
984 }
985 
986 /*
987  * Check for CPU features that are used in early boot
988  * based on the Boot CPU value.
989  */
990 static void check_early_cpu_features(void)
991 {
992 	verify_cpu_run_el();
993 	verify_cpu_asid_bits();
994 }
995 
996 static void
997 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
998 {
999 
1000 	for (; caps->matches; caps++)
1001 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
1002 			pr_crit("CPU%d: missing HWCAP: %s\n",
1003 					smp_processor_id(), caps->desc);
1004 			cpu_die_early();
1005 		}
1006 }
1007 
1008 static void
1009 verify_local_cpu_features(const struct arm64_cpu_capabilities *caps)
1010 {
1011 	for (; caps->matches; caps++) {
1012 		if (!cpus_have_cap(caps->capability))
1013 			continue;
1014 		/*
1015 		 * If the new CPU misses an advertised feature, we cannot proceed
1016 		 * further, park the cpu.
1017 		 */
1018 		if (!caps->matches(caps, SCOPE_LOCAL_CPU)) {
1019 			pr_crit("CPU%d: missing feature: %s\n",
1020 					smp_processor_id(), caps->desc);
1021 			cpu_die_early();
1022 		}
1023 		if (caps->enable)
1024 			caps->enable(NULL);
1025 	}
1026 }
1027 
1028 /*
1029  * Run through the enabled system capabilities and enable() it on this CPU.
1030  * The capabilities were decided based on the available CPUs at the boot time.
1031  * Any new CPU should match the system wide status of the capability. If the
1032  * new CPU doesn't have a capability which the system now has enabled, we
1033  * cannot do anything to fix it up and could cause unexpected failures. So
1034  * we park the CPU.
1035  */
1036 static void verify_local_cpu_capabilities(void)
1037 {
1038 	verify_local_cpu_errata_workarounds();
1039 	verify_local_cpu_features(arm64_features);
1040 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
1041 	if (system_supports_32bit_el0())
1042 		verify_local_elf_hwcaps(compat_elf_hwcaps);
1043 }
1044 
1045 void check_local_cpu_capabilities(void)
1046 {
1047 	/*
1048 	 * All secondary CPUs should conform to the early CPU features
1049 	 * in use by the kernel based on boot CPU.
1050 	 */
1051 	check_early_cpu_features();
1052 
1053 	/*
1054 	 * If we haven't finalised the system capabilities, this CPU gets
1055 	 * a chance to update the errata work arounds.
1056 	 * Otherwise, this CPU should verify that it has all the system
1057 	 * advertised capabilities.
1058 	 */
1059 	if (!sys_caps_initialised)
1060 		update_cpu_errata_workarounds();
1061 	else
1062 		verify_local_cpu_capabilities();
1063 }
1064 
1065 static void __init setup_feature_capabilities(void)
1066 {
1067 	update_cpu_capabilities(arm64_features, "detected feature:");
1068 	enable_cpu_capabilities(arm64_features);
1069 }
1070 
1071 /*
1072  * Check if the current CPU has a given feature capability.
1073  * Should be called from non-preemptible context.
1074  */
1075 bool this_cpu_has_cap(unsigned int cap)
1076 {
1077 	const struct arm64_cpu_capabilities *caps;
1078 
1079 	if (WARN_ON(preemptible()))
1080 		return false;
1081 
1082 	for (caps = arm64_features; caps->desc; caps++)
1083 		if (caps->capability == cap && caps->matches)
1084 			return caps->matches(caps, SCOPE_LOCAL_CPU);
1085 
1086 	return false;
1087 }
1088 
1089 void __init setup_cpu_features(void)
1090 {
1091 	u32 cwg;
1092 	int cls;
1093 
1094 	/* Set the CPU feature capabilies */
1095 	setup_feature_capabilities();
1096 	enable_errata_workarounds();
1097 	setup_elf_hwcaps(arm64_elf_hwcaps);
1098 
1099 	if (system_supports_32bit_el0())
1100 		setup_elf_hwcaps(compat_elf_hwcaps);
1101 
1102 	/* Advertise that we have computed the system capabilities */
1103 	set_sys_caps_initialised();
1104 
1105 	/*
1106 	 * Check for sane CTR_EL0.CWG value.
1107 	 */
1108 	cwg = cache_type_cwg();
1109 	cls = cache_line_size();
1110 	if (!cwg)
1111 		pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
1112 			cls);
1113 	if (L1_CACHE_BYTES < cls)
1114 		pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
1115 			L1_CACHE_BYTES, cls);
1116 }
1117 
1118 static bool __maybe_unused
1119 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
1120 {
1121 	return (cpus_have_const_cap(ARM64_HAS_PAN) && !cpus_have_const_cap(ARM64_HAS_UAO));
1122 }
1123