xref: /linux/arch/arm64/kernel/cpufeature.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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/sort.h>
23 #include <linux/types.h>
24 #include <asm/cpu.h>
25 #include <asm/cpufeature.h>
26 #include <asm/cpu_ops.h>
27 #include <asm/mmu_context.h>
28 #include <asm/processor.h>
29 #include <asm/sysreg.h>
30 #include <asm/virt.h>
31 
32 unsigned long elf_hwcap __read_mostly;
33 EXPORT_SYMBOL_GPL(elf_hwcap);
34 
35 #ifdef CONFIG_COMPAT
36 #define COMPAT_ELF_HWCAP_DEFAULT	\
37 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
38 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
39 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
40 				 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
41 				 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
42 				 COMPAT_HWCAP_LPAE)
43 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
44 unsigned int compat_elf_hwcap2 __read_mostly;
45 #endif
46 
47 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
48 
49 #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
50 	{						\
51 		.sign = SIGNED,				\
52 		.strict = STRICT,			\
53 		.type = TYPE,				\
54 		.shift = SHIFT,				\
55 		.width = WIDTH,				\
56 		.safe_val = SAFE_VAL,			\
57 	}
58 
59 /* Define a feature with unsigned values */
60 #define ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
61 	__ARM64_FTR_BITS(FTR_UNSIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
62 
63 /* Define a feature with a signed value */
64 #define S_ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
65 	__ARM64_FTR_BITS(FTR_SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
66 
67 #define ARM64_FTR_END					\
68 	{						\
69 		.width = 0,				\
70 	}
71 
72 /* meta feature for alternatives */
73 static bool __maybe_unused
74 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
75 
76 
77 static struct arm64_ftr_bits ftr_id_aa64isar0[] = {
78 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
79 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
80 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),
81 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
82 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
83 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
84 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
85 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
86 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* RAZ */
87 	ARM64_FTR_END,
88 };
89 
90 static struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
91 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
92 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0),
93 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_GIC_SHIFT, 4, 0),
94 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
95 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
96 	/* Linux doesn't care about the EL3 */
97 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64PFR0_EL3_SHIFT, 4, 0),
98 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL2_SHIFT, 4, 0),
99 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
100 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
101 	ARM64_FTR_END,
102 };
103 
104 static struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
105 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
106 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
107 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
108 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
109 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
110 	/* Linux shouldn't care about secure memory */
111 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
112 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
113 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
114 	/*
115 	 * Differing PARange is fine as long as all peripherals and memory are mapped
116 	 * within the minimum PARange of all CPUs
117 	 */
118 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
119 	ARM64_FTR_END,
120 };
121 
122 static struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
123 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
124 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
125 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
126 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
127 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
128 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
129 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
130 	ARM64_FTR_END,
131 };
132 
133 static struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
134 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
135 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
136 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
137 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
138 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
139 	ARM64_FTR_END,
140 };
141 
142 static struct arm64_ftr_bits ftr_ctr[] = {
143 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1),	/* RAO */
144 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 3, 0),
145 	ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0),	/* CWG */
146 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* ERG */
147 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1),	/* DminLine */
148 	/*
149 	 * Linux can handle differing I-cache policies. Userspace JITs will
150 	 * make use of *minLine
151 	 */
152 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, 0),	/* L1Ip */
153 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 10, 0),	/* RAZ */
154 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* IminLine */
155 	ARM64_FTR_END,
156 };
157 
158 static struct arm64_ftr_bits ftr_id_mmfr0[] = {
159 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0xf),	/* InnerShr */
160 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),	/* FCSE */
161 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* AuxReg */
162 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 4, 0),	/* TCM */
163 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* ShareLvl */
164 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0xf),	/* OuterShr */
165 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),	/* PMSA */
166 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* VMSA */
167 	ARM64_FTR_END,
168 };
169 
170 static struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
171 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
172 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
173 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
174 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
175 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
176 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
178 	ARM64_FTR_END,
179 };
180 
181 static struct arm64_ftr_bits ftr_mvfr2[] = {
182 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
183 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* FPMisc */
184 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* SIMDMisc */
185 	ARM64_FTR_END,
186 };
187 
188 static struct arm64_ftr_bits ftr_dczid[] = {
189 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 5, 27, 0),	/* RAZ */
190 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 1, 1),		/* DZP */
191 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* BS */
192 	ARM64_FTR_END,
193 };
194 
195 
196 static struct arm64_ftr_bits ftr_id_isar5[] = {
197 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_RDM_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 20, 4, 0),	/* RAZ */
199 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_CRC32_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA2_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA1_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_AES_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SEVL_SHIFT, 4, 0),
204 	ARM64_FTR_END,
205 };
206 
207 static struct arm64_ftr_bits ftr_id_mmfr4[] = {
208 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
209 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* ac2 */
210 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* RAZ */
211 	ARM64_FTR_END,
212 };
213 
214 static struct arm64_ftr_bits ftr_id_pfr0[] = {
215 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 16, 0),	/* RAZ */
216 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* State3 */
217 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0),		/* State2 */
218 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* State1 */
219 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* State0 */
220 	ARM64_FTR_END,
221 };
222 
223 static struct arm64_ftr_bits ftr_id_dfr0[] = {
224 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
225 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf),	/* PerfMon */
226 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
227 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
228 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
229 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
230 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
231 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
232 	ARM64_FTR_END,
233 };
234 
235 /*
236  * Common ftr bits for a 32bit register with all hidden, strict
237  * attributes, with 4bit feature fields and a default safe value of
238  * 0. Covers the following 32bit registers:
239  * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
240  */
241 static struct arm64_ftr_bits ftr_generic_32bits[] = {
242 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
243 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
244 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
245 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
246 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
247 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
248 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
249 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
250 	ARM64_FTR_END,
251 };
252 
253 static struct arm64_ftr_bits ftr_generic[] = {
254 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
255 	ARM64_FTR_END,
256 };
257 
258 static struct arm64_ftr_bits ftr_generic32[] = {
259 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 32, 0),
260 	ARM64_FTR_END,
261 };
262 
263 static struct arm64_ftr_bits ftr_aa64raz[] = {
264 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
265 	ARM64_FTR_END,
266 };
267 
268 #define ARM64_FTR_REG(id, table)		\
269 	{					\
270 		.sys_id = id,			\
271 		.name = #id,			\
272 		.ftr_bits = &((table)[0]),	\
273 	}
274 
275 static struct arm64_ftr_reg arm64_ftr_regs[] = {
276 
277 	/* Op1 = 0, CRn = 0, CRm = 1 */
278 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
279 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
280 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
281 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
282 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
283 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
284 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
285 
286 	/* Op1 = 0, CRn = 0, CRm = 2 */
287 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
288 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
289 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
290 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
291 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
292 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
293 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
294 
295 	/* Op1 = 0, CRn = 0, CRm = 3 */
296 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
297 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
298 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
299 
300 	/* Op1 = 0, CRn = 0, CRm = 4 */
301 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
302 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_aa64raz),
303 
304 	/* Op1 = 0, CRn = 0, CRm = 5 */
305 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
306 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_generic),
307 
308 	/* Op1 = 0, CRn = 0, CRm = 6 */
309 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
310 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz),
311 
312 	/* Op1 = 0, CRn = 0, CRm = 7 */
313 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
314 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
315 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
316 
317 	/* Op1 = 3, CRn = 0, CRm = 0 */
318 	ARM64_FTR_REG(SYS_CTR_EL0, ftr_ctr),
319 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
320 
321 	/* Op1 = 3, CRn = 14, CRm = 0 */
322 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_generic32),
323 };
324 
325 static int search_cmp_ftr_reg(const void *id, const void *regp)
326 {
327 	return (int)(unsigned long)id - (int)((const struct arm64_ftr_reg *)regp)->sys_id;
328 }
329 
330 /*
331  * get_arm64_ftr_reg - Lookup a feature register entry using its
332  * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
333  * ascending order of sys_id , we use binary search to find a matching
334  * entry.
335  *
336  * returns - Upon success,  matching ftr_reg entry for id.
337  *         - NULL on failure. It is upto the caller to decide
338  *	     the impact of a failure.
339  */
340 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
341 {
342 	return bsearch((const void *)(unsigned long)sys_id,
343 			arm64_ftr_regs,
344 			ARRAY_SIZE(arm64_ftr_regs),
345 			sizeof(arm64_ftr_regs[0]),
346 			search_cmp_ftr_reg);
347 }
348 
349 static u64 arm64_ftr_set_value(struct arm64_ftr_bits *ftrp, s64 reg, s64 ftr_val)
350 {
351 	u64 mask = arm64_ftr_mask(ftrp);
352 
353 	reg &= ~mask;
354 	reg |= (ftr_val << ftrp->shift) & mask;
355 	return reg;
356 }
357 
358 static s64 arm64_ftr_safe_value(struct arm64_ftr_bits *ftrp, s64 new, s64 cur)
359 {
360 	s64 ret = 0;
361 
362 	switch (ftrp->type) {
363 	case FTR_EXACT:
364 		ret = ftrp->safe_val;
365 		break;
366 	case FTR_LOWER_SAFE:
367 		ret = new < cur ? new : cur;
368 		break;
369 	case FTR_HIGHER_SAFE:
370 		ret = new > cur ? new : cur;
371 		break;
372 	default:
373 		BUG();
374 	}
375 
376 	return ret;
377 }
378 
379 static int __init sort_cmp_ftr_regs(const void *a, const void *b)
380 {
381 	return ((const struct arm64_ftr_reg *)a)->sys_id -
382 		 ((const struct arm64_ftr_reg *)b)->sys_id;
383 }
384 
385 static void __init swap_ftr_regs(void *a, void *b, int size)
386 {
387 	struct arm64_ftr_reg tmp = *(struct arm64_ftr_reg *)a;
388 	*(struct arm64_ftr_reg *)a = *(struct arm64_ftr_reg *)b;
389 	*(struct arm64_ftr_reg *)b = tmp;
390 }
391 
392 static void __init sort_ftr_regs(void)
393 {
394 	/* Keep the array sorted so that we can do the binary search */
395 	sort(arm64_ftr_regs,
396 		ARRAY_SIZE(arm64_ftr_regs),
397 		sizeof(arm64_ftr_regs[0]),
398 		sort_cmp_ftr_regs,
399 		swap_ftr_regs);
400 }
401 
402 /*
403  * Initialise the CPU feature register from Boot CPU values.
404  * Also initiliases the strict_mask for the register.
405  */
406 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
407 {
408 	u64 val = 0;
409 	u64 strict_mask = ~0x0ULL;
410 	struct arm64_ftr_bits *ftrp;
411 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
412 
413 	BUG_ON(!reg);
414 
415 	for (ftrp  = reg->ftr_bits; ftrp->width; ftrp++) {
416 		s64 ftr_new = arm64_ftr_value(ftrp, new);
417 
418 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
419 		if (!ftrp->strict)
420 			strict_mask &= ~arm64_ftr_mask(ftrp);
421 	}
422 	reg->sys_val = val;
423 	reg->strict_mask = strict_mask;
424 }
425 
426 void __init init_cpu_features(struct cpuinfo_arm64 *info)
427 {
428 	/* Before we start using the tables, make sure it is sorted */
429 	sort_ftr_regs();
430 
431 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
432 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
433 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
434 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
435 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
436 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
437 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
438 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
439 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
440 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
441 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
442 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
443 
444 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
445 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
446 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
447 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
448 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
449 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
450 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
451 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
452 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
453 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
454 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
455 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
456 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
457 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
458 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
459 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
460 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
461 	}
462 
463 }
464 
465 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
466 {
467 	struct arm64_ftr_bits *ftrp;
468 
469 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
470 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
471 		s64 ftr_new = arm64_ftr_value(ftrp, new);
472 
473 		if (ftr_cur == ftr_new)
474 			continue;
475 		/* Find a safe value */
476 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
477 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
478 	}
479 
480 }
481 
482 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
483 {
484 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
485 
486 	BUG_ON(!regp);
487 	update_cpu_ftr_reg(regp, val);
488 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
489 		return 0;
490 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
491 			regp->name, boot, cpu, val);
492 	return 1;
493 }
494 
495 /*
496  * Update system wide CPU feature registers with the values from a
497  * non-boot CPU. Also performs SANITY checks to make sure that there
498  * aren't any insane variations from that of the boot CPU.
499  */
500 void update_cpu_features(int cpu,
501 			 struct cpuinfo_arm64 *info,
502 			 struct cpuinfo_arm64 *boot)
503 {
504 	int taint = 0;
505 
506 	/*
507 	 * The kernel can handle differing I-cache policies, but otherwise
508 	 * caches should look identical. Userspace JITs will make use of
509 	 * *minLine.
510 	 */
511 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
512 				      info->reg_ctr, boot->reg_ctr);
513 
514 	/*
515 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
516 	 * could result in too much or too little memory being zeroed if a
517 	 * process is preempted and migrated between CPUs.
518 	 */
519 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
520 				      info->reg_dczid, boot->reg_dczid);
521 
522 	/* If different, timekeeping will be broken (especially with KVM) */
523 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
524 				      info->reg_cntfrq, boot->reg_cntfrq);
525 
526 	/*
527 	 * The kernel uses self-hosted debug features and expects CPUs to
528 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
529 	 * and BRPs to be identical.
530 	 * ID_AA64DFR1 is currently RES0.
531 	 */
532 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
533 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
534 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
535 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
536 	/*
537 	 * Even in big.LITTLE, processors should be identical instruction-set
538 	 * wise.
539 	 */
540 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
541 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
542 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
543 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
544 
545 	/*
546 	 * Differing PARange support is fine as long as all peripherals and
547 	 * memory are mapped within the minimum PARange of all CPUs.
548 	 * Linux should not care about secure memory.
549 	 */
550 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
551 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
552 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
553 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
554 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
555 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
556 
557 	/*
558 	 * EL3 is not our concern.
559 	 * ID_AA64PFR1 is currently RES0.
560 	 */
561 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
562 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
563 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
564 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
565 
566 	/*
567 	 * If we have AArch32, we care about 32-bit features for compat.
568 	 * If the system doesn't support AArch32, don't update them.
569 	 */
570 	if (id_aa64pfr0_32bit_el0(read_system_reg(SYS_ID_AA64PFR0_EL1)) &&
571 		id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
572 
573 		taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
574 					info->reg_id_dfr0, boot->reg_id_dfr0);
575 		taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
576 					info->reg_id_isar0, boot->reg_id_isar0);
577 		taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
578 					info->reg_id_isar1, boot->reg_id_isar1);
579 		taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
580 					info->reg_id_isar2, boot->reg_id_isar2);
581 		taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
582 					info->reg_id_isar3, boot->reg_id_isar3);
583 		taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
584 					info->reg_id_isar4, boot->reg_id_isar4);
585 		taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
586 					info->reg_id_isar5, boot->reg_id_isar5);
587 
588 		/*
589 		 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
590 		 * ACTLR formats could differ across CPUs and therefore would have to
591 		 * be trapped for virtualization anyway.
592 		 */
593 		taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
594 					info->reg_id_mmfr0, boot->reg_id_mmfr0);
595 		taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
596 					info->reg_id_mmfr1, boot->reg_id_mmfr1);
597 		taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
598 					info->reg_id_mmfr2, boot->reg_id_mmfr2);
599 		taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
600 					info->reg_id_mmfr3, boot->reg_id_mmfr3);
601 		taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
602 					info->reg_id_pfr0, boot->reg_id_pfr0);
603 		taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
604 					info->reg_id_pfr1, boot->reg_id_pfr1);
605 		taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
606 					info->reg_mvfr0, boot->reg_mvfr0);
607 		taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
608 					info->reg_mvfr1, boot->reg_mvfr1);
609 		taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
610 					info->reg_mvfr2, boot->reg_mvfr2);
611 	}
612 
613 	/*
614 	 * Mismatched CPU features are a recipe for disaster. Don't even
615 	 * pretend to support them.
616 	 */
617 	WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC,
618 			"Unsupported CPU feature variation.\n");
619 }
620 
621 u64 read_system_reg(u32 id)
622 {
623 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
624 
625 	/* We shouldn't get a request for an unsupported register */
626 	BUG_ON(!regp);
627 	return regp->sys_val;
628 }
629 
630 /*
631  * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated.
632  * Read the system register on the current CPU
633  */
634 static u64 __raw_read_system_reg(u32 sys_id)
635 {
636 	switch (sys_id) {
637 	case SYS_ID_PFR0_EL1:		return read_cpuid(ID_PFR0_EL1);
638 	case SYS_ID_PFR1_EL1:		return read_cpuid(ID_PFR1_EL1);
639 	case SYS_ID_DFR0_EL1:		return read_cpuid(ID_DFR0_EL1);
640 	case SYS_ID_MMFR0_EL1:		return read_cpuid(ID_MMFR0_EL1);
641 	case SYS_ID_MMFR1_EL1:		return read_cpuid(ID_MMFR1_EL1);
642 	case SYS_ID_MMFR2_EL1:		return read_cpuid(ID_MMFR2_EL1);
643 	case SYS_ID_MMFR3_EL1:		return read_cpuid(ID_MMFR3_EL1);
644 	case SYS_ID_ISAR0_EL1:		return read_cpuid(ID_ISAR0_EL1);
645 	case SYS_ID_ISAR1_EL1:		return read_cpuid(ID_ISAR1_EL1);
646 	case SYS_ID_ISAR2_EL1:		return read_cpuid(ID_ISAR2_EL1);
647 	case SYS_ID_ISAR3_EL1:		return read_cpuid(ID_ISAR3_EL1);
648 	case SYS_ID_ISAR4_EL1:		return read_cpuid(ID_ISAR4_EL1);
649 	case SYS_ID_ISAR5_EL1:		return read_cpuid(ID_ISAR4_EL1);
650 	case SYS_MVFR0_EL1:		return read_cpuid(MVFR0_EL1);
651 	case SYS_MVFR1_EL1:		return read_cpuid(MVFR1_EL1);
652 	case SYS_MVFR2_EL1:		return read_cpuid(MVFR2_EL1);
653 
654 	case SYS_ID_AA64PFR0_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
655 	case SYS_ID_AA64PFR1_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
656 	case SYS_ID_AA64DFR0_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
657 	case SYS_ID_AA64DFR1_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
658 	case SYS_ID_AA64MMFR0_EL1:	return read_cpuid(ID_AA64MMFR0_EL1);
659 	case SYS_ID_AA64MMFR1_EL1:	return read_cpuid(ID_AA64MMFR1_EL1);
660 	case SYS_ID_AA64MMFR2_EL1:	return read_cpuid(ID_AA64MMFR2_EL1);
661 	case SYS_ID_AA64ISAR0_EL1:	return read_cpuid(ID_AA64ISAR0_EL1);
662 	case SYS_ID_AA64ISAR1_EL1:	return read_cpuid(ID_AA64ISAR1_EL1);
663 
664 	case SYS_CNTFRQ_EL0:		return read_cpuid(CNTFRQ_EL0);
665 	case SYS_CTR_EL0:		return read_cpuid(CTR_EL0);
666 	case SYS_DCZID_EL0:		return read_cpuid(DCZID_EL0);
667 	default:
668 		BUG();
669 		return 0;
670 	}
671 }
672 
673 #include <linux/irqchip/arm-gic-v3.h>
674 
675 static bool
676 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
677 {
678 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
679 
680 	return val >= entry->min_field_value;
681 }
682 
683 static bool
684 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
685 {
686 	u64 val;
687 
688 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
689 	if (scope == SCOPE_SYSTEM)
690 		val = read_system_reg(entry->sys_reg);
691 	else
692 		val = __raw_read_system_reg(entry->sys_reg);
693 
694 	return feature_matches(val, entry);
695 }
696 
697 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
698 {
699 	bool has_sre;
700 
701 	if (!has_cpuid_feature(entry, scope))
702 		return false;
703 
704 	has_sre = gic_enable_sre();
705 	if (!has_sre)
706 		pr_warn_once("%s present but disabled by higher exception level\n",
707 			     entry->desc);
708 
709 	return has_sre;
710 }
711 
712 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
713 {
714 	u32 midr = read_cpuid_id();
715 	u32 rv_min, rv_max;
716 
717 	/* Cavium ThunderX pass 1.x and 2.x */
718 	rv_min = 0;
719 	rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK;
720 
721 	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max);
722 }
723 
724 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
725 {
726 	return is_kernel_in_hyp_mode();
727 }
728 
729 static const struct arm64_cpu_capabilities arm64_features[] = {
730 	{
731 		.desc = "GIC system register CPU interface",
732 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
733 		.def_scope = SCOPE_SYSTEM,
734 		.matches = has_useable_gicv3_cpuif,
735 		.sys_reg = SYS_ID_AA64PFR0_EL1,
736 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
737 		.sign = FTR_UNSIGNED,
738 		.min_field_value = 1,
739 	},
740 #ifdef CONFIG_ARM64_PAN
741 	{
742 		.desc = "Privileged Access Never",
743 		.capability = ARM64_HAS_PAN,
744 		.def_scope = SCOPE_SYSTEM,
745 		.matches = has_cpuid_feature,
746 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
747 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
748 		.sign = FTR_UNSIGNED,
749 		.min_field_value = 1,
750 		.enable = cpu_enable_pan,
751 	},
752 #endif /* CONFIG_ARM64_PAN */
753 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
754 	{
755 		.desc = "LSE atomic instructions",
756 		.capability = ARM64_HAS_LSE_ATOMICS,
757 		.def_scope = SCOPE_SYSTEM,
758 		.matches = has_cpuid_feature,
759 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
760 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
761 		.sign = FTR_UNSIGNED,
762 		.min_field_value = 2,
763 	},
764 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
765 	{
766 		.desc = "Software prefetching using PRFM",
767 		.capability = ARM64_HAS_NO_HW_PREFETCH,
768 		.def_scope = SCOPE_SYSTEM,
769 		.matches = has_no_hw_prefetch,
770 	},
771 #ifdef CONFIG_ARM64_UAO
772 	{
773 		.desc = "User Access Override",
774 		.capability = ARM64_HAS_UAO,
775 		.def_scope = SCOPE_SYSTEM,
776 		.matches = has_cpuid_feature,
777 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
778 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
779 		.min_field_value = 1,
780 		.enable = cpu_enable_uao,
781 	},
782 #endif /* CONFIG_ARM64_UAO */
783 #ifdef CONFIG_ARM64_PAN
784 	{
785 		.capability = ARM64_ALT_PAN_NOT_UAO,
786 		.def_scope = SCOPE_SYSTEM,
787 		.matches = cpufeature_pan_not_uao,
788 	},
789 #endif /* CONFIG_ARM64_PAN */
790 	{
791 		.desc = "Virtualization Host Extensions",
792 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
793 		.def_scope = SCOPE_SYSTEM,
794 		.matches = runs_at_el2,
795 	},
796 	{
797 		.desc = "32-bit EL0 Support",
798 		.capability = ARM64_HAS_32BIT_EL0,
799 		.def_scope = SCOPE_SYSTEM,
800 		.matches = has_cpuid_feature,
801 		.sys_reg = SYS_ID_AA64PFR0_EL1,
802 		.sign = FTR_UNSIGNED,
803 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
804 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
805 	},
806 	{},
807 };
808 
809 #define HWCAP_CAP(reg, field, s, min_value, type, cap)	\
810 	{							\
811 		.desc = #cap,					\
812 		.def_scope = SCOPE_SYSTEM,			\
813 		.matches = has_cpuid_feature,			\
814 		.sys_reg = reg,					\
815 		.field_pos = field,				\
816 		.sign = s,					\
817 		.min_field_value = min_value,			\
818 		.hwcap_type = type,				\
819 		.hwcap = cap,					\
820 	}
821 
822 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
823 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_PMULL),
824 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES),
825 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1),
826 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2),
827 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32),
828 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
829 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
830 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP),
831 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
832 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP),
833 	{},
834 };
835 
836 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
837 #ifdef CONFIG_COMPAT
838 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
839 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
840 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
841 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
842 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
843 #endif
844 	{},
845 };
846 
847 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
848 {
849 	switch (cap->hwcap_type) {
850 	case CAP_HWCAP:
851 		elf_hwcap |= cap->hwcap;
852 		break;
853 #ifdef CONFIG_COMPAT
854 	case CAP_COMPAT_HWCAP:
855 		compat_elf_hwcap |= (u32)cap->hwcap;
856 		break;
857 	case CAP_COMPAT_HWCAP2:
858 		compat_elf_hwcap2 |= (u32)cap->hwcap;
859 		break;
860 #endif
861 	default:
862 		WARN_ON(1);
863 		break;
864 	}
865 }
866 
867 /* Check if we have a particular HWCAP enabled */
868 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
869 {
870 	bool rc;
871 
872 	switch (cap->hwcap_type) {
873 	case CAP_HWCAP:
874 		rc = (elf_hwcap & cap->hwcap) != 0;
875 		break;
876 #ifdef CONFIG_COMPAT
877 	case CAP_COMPAT_HWCAP:
878 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
879 		break;
880 	case CAP_COMPAT_HWCAP2:
881 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
882 		break;
883 #endif
884 	default:
885 		WARN_ON(1);
886 		rc = false;
887 	}
888 
889 	return rc;
890 }
891 
892 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
893 {
894 	for (; hwcaps->matches; hwcaps++)
895 		if (hwcaps->matches(hwcaps, hwcaps->def_scope))
896 			cap_set_elf_hwcap(hwcaps);
897 }
898 
899 void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
900 			    const char *info)
901 {
902 	for (; caps->matches; caps++) {
903 		if (!caps->matches(caps, caps->def_scope))
904 			continue;
905 
906 		if (!cpus_have_cap(caps->capability) && caps->desc)
907 			pr_info("%s %s\n", info, caps->desc);
908 		cpus_set_cap(caps->capability);
909 	}
910 }
911 
912 /*
913  * Run through the enabled capabilities and enable() it on all active
914  * CPUs
915  */
916 static void __init
917 enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
918 {
919 	for (; caps->matches; caps++)
920 		if (caps->enable && cpus_have_cap(caps->capability))
921 			on_each_cpu(caps->enable, NULL, true);
922 }
923 
924 /*
925  * Flag to indicate if we have computed the system wide
926  * capabilities based on the boot time active CPUs. This
927  * will be used to determine if a new booting CPU should
928  * go through the verification process to make sure that it
929  * supports the system capabilities, without using a hotplug
930  * notifier.
931  */
932 static bool sys_caps_initialised;
933 
934 static inline void set_sys_caps_initialised(void)
935 {
936 	sys_caps_initialised = true;
937 }
938 
939 /*
940  * Check for CPU features that are used in early boot
941  * based on the Boot CPU value.
942  */
943 static void check_early_cpu_features(void)
944 {
945 	verify_cpu_run_el();
946 	verify_cpu_asid_bits();
947 }
948 
949 static void
950 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
951 {
952 
953 	for (; caps->matches; caps++)
954 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
955 			pr_crit("CPU%d: missing HWCAP: %s\n",
956 					smp_processor_id(), caps->desc);
957 			cpu_die_early();
958 		}
959 }
960 
961 static void
962 verify_local_cpu_features(const struct arm64_cpu_capabilities *caps)
963 {
964 	for (; caps->matches; caps++) {
965 		if (!cpus_have_cap(caps->capability))
966 			continue;
967 		/*
968 		 * If the new CPU misses an advertised feature, we cannot proceed
969 		 * further, park the cpu.
970 		 */
971 		if (!caps->matches(caps, SCOPE_LOCAL_CPU)) {
972 			pr_crit("CPU%d: missing feature: %s\n",
973 					smp_processor_id(), caps->desc);
974 			cpu_die_early();
975 		}
976 		if (caps->enable)
977 			caps->enable(NULL);
978 	}
979 }
980 
981 /*
982  * Run through the enabled system capabilities and enable() it on this CPU.
983  * The capabilities were decided based on the available CPUs at the boot time.
984  * Any new CPU should match the system wide status of the capability. If the
985  * new CPU doesn't have a capability which the system now has enabled, we
986  * cannot do anything to fix it up and could cause unexpected failures. So
987  * we park the CPU.
988  */
989 void verify_local_cpu_capabilities(void)
990 {
991 
992 	check_early_cpu_features();
993 
994 	/*
995 	 * If we haven't computed the system capabilities, there is nothing
996 	 * to verify.
997 	 */
998 	if (!sys_caps_initialised)
999 		return;
1000 
1001 	verify_local_cpu_errata();
1002 	verify_local_cpu_features(arm64_features);
1003 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
1004 	if (system_supports_32bit_el0())
1005 		verify_local_elf_hwcaps(compat_elf_hwcaps);
1006 }
1007 
1008 static void __init setup_feature_capabilities(void)
1009 {
1010 	update_cpu_capabilities(arm64_features, "detected feature:");
1011 	enable_cpu_capabilities(arm64_features);
1012 }
1013 
1014 /*
1015  * Check if the current CPU has a given feature capability.
1016  * Should be called from non-preemptible context.
1017  */
1018 bool this_cpu_has_cap(unsigned int cap)
1019 {
1020 	const struct arm64_cpu_capabilities *caps;
1021 
1022 	if (WARN_ON(preemptible()))
1023 		return false;
1024 
1025 	for (caps = arm64_features; caps->desc; caps++)
1026 		if (caps->capability == cap && caps->matches)
1027 			return caps->matches(caps, SCOPE_LOCAL_CPU);
1028 
1029 	return false;
1030 }
1031 
1032 void __init setup_cpu_features(void)
1033 {
1034 	u32 cwg;
1035 	int cls;
1036 
1037 	/* Set the CPU feature capabilies */
1038 	setup_feature_capabilities();
1039 	setup_elf_hwcaps(arm64_elf_hwcaps);
1040 
1041 	if (system_supports_32bit_el0())
1042 		setup_elf_hwcaps(compat_elf_hwcaps);
1043 
1044 	/* Advertise that we have computed the system capabilities */
1045 	set_sys_caps_initialised();
1046 
1047 	/*
1048 	 * Check for sane CTR_EL0.CWG value.
1049 	 */
1050 	cwg = cache_type_cwg();
1051 	cls = cache_line_size();
1052 	if (!cwg)
1053 		pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
1054 			cls);
1055 	if (L1_CACHE_BYTES < cls)
1056 		pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
1057 			L1_CACHE_BYTES, cls);
1058 }
1059 
1060 static bool __maybe_unused
1061 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
1062 {
1063 	return (cpus_have_cap(ARM64_HAS_PAN) && !cpus_have_cap(ARM64_HAS_UAO));
1064 }
1065