xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision e983940270f10fe8551baf0098be76ea478294a3)
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_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
50 EXPORT_SYMBOL(cpu_hwcap_keys);
51 
52 #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
53 	{						\
54 		.sign = SIGNED,				\
55 		.strict = STRICT,			\
56 		.type = TYPE,				\
57 		.shift = SHIFT,				\
58 		.width = WIDTH,				\
59 		.safe_val = SAFE_VAL,			\
60 	}
61 
62 /* Define a feature with unsigned values */
63 #define ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
64 	__ARM64_FTR_BITS(FTR_UNSIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
65 
66 /* Define a feature with a signed value */
67 #define S_ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
68 	__ARM64_FTR_BITS(FTR_SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
69 
70 #define ARM64_FTR_END					\
71 	{						\
72 		.width = 0,				\
73 	}
74 
75 /* meta feature for alternatives */
76 static bool __maybe_unused
77 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
78 
79 
80 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
81 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
82 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
83 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),
84 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
85 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
86 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
87 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
88 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
89 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* RAZ */
90 	ARM64_FTR_END,
91 };
92 
93 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
94 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
95 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0),
96 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_GIC_SHIFT, 4, 0),
97 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
98 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
99 	/* Linux doesn't care about the EL3 */
100 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64PFR0_EL3_SHIFT, 4, 0),
101 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL2_SHIFT, 4, 0),
102 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
103 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
104 	ARM64_FTR_END,
105 };
106 
107 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
108 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
109 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
110 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
111 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
112 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
113 	/* Linux shouldn't care about secure memory */
114 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
115 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
116 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
117 	/*
118 	 * Differing PARange is fine as long as all peripherals and memory are mapped
119 	 * within the minimum PARange of all CPUs
120 	 */
121 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
122 	ARM64_FTR_END,
123 };
124 
125 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
126 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
127 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
128 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
129 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
130 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
131 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
132 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
133 	ARM64_FTR_END,
134 };
135 
136 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
137 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
138 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
139 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
140 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
141 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
142 	ARM64_FTR_END,
143 };
144 
145 static const struct arm64_ftr_bits ftr_ctr[] = {
146 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1),	/* RAO */
147 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 3, 0),
148 	ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0),	/* CWG */
149 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* ERG */
150 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1),	/* DminLine */
151 	/*
152 	 * Linux can handle differing I-cache policies. Userspace JITs will
153 	 * make use of *minLine.
154 	 * If we have differing I-cache policies, report it as the weakest - AIVIVT.
155 	 */
156 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_AIVIVT),	/* L1Ip */
157 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 10, 0),	/* RAZ */
158 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* IminLine */
159 	ARM64_FTR_END,
160 };
161 
162 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
163 	.name		= "SYS_CTR_EL0",
164 	.ftr_bits	= ftr_ctr
165 };
166 
167 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
168 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0xf),	/* InnerShr */
169 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),	/* FCSE */
170 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0),	/* AuxReg */
171 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 4, 0),	/* TCM */
172 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* ShareLvl */
173 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0xf),	/* OuterShr */
174 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),	/* PMSA */
175 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),	/* VMSA */
176 	ARM64_FTR_END,
177 };
178 
179 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
180 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
181 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
182 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
183 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
184 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
187 	ARM64_FTR_END,
188 };
189 
190 static const struct arm64_ftr_bits ftr_mvfr2[] = {
191 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
192 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* FPMisc */
193 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* SIMDMisc */
194 	ARM64_FTR_END,
195 };
196 
197 static const struct arm64_ftr_bits ftr_dczid[] = {
198 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 5, 27, 0),	/* RAZ */
199 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 1, 1),		/* DZP */
200 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* BS */
201 	ARM64_FTR_END,
202 };
203 
204 
205 static const struct arm64_ftr_bits ftr_id_isar5[] = {
206 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_RDM_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 20, 4, 0),	/* RAZ */
208 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_CRC32_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA2_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA1_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_AES_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SEVL_SHIFT, 4, 0),
213 	ARM64_FTR_END,
214 };
215 
216 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
217 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0),	/* RAZ */
218 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* ac2 */
219 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* RAZ */
220 	ARM64_FTR_END,
221 };
222 
223 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
224 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 16, 0),	/* RAZ */
225 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0),	/* State3 */
226 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0),		/* State2 */
227 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0),		/* State1 */
228 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0),		/* State0 */
229 	ARM64_FTR_END,
230 };
231 
232 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
233 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
234 	S_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf),	/* PerfMon */
235 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
236 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
237 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
238 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
239 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
240 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
241 	ARM64_FTR_END,
242 };
243 
244 /*
245  * Common ftr bits for a 32bit register with all hidden, strict
246  * attributes, with 4bit feature fields and a default safe value of
247  * 0. Covers the following 32bit registers:
248  * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
249  */
250 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
251 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
252 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
253 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
254 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
255 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
256 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
257 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
258 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
259 	ARM64_FTR_END,
260 };
261 
262 static const struct arm64_ftr_bits ftr_generic[] = {
263 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
264 	ARM64_FTR_END,
265 };
266 
267 static const struct arm64_ftr_bits ftr_generic32[] = {
268 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 32, 0),
269 	ARM64_FTR_END,
270 };
271 
272 static const struct arm64_ftr_bits ftr_aa64raz[] = {
273 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
274 	ARM64_FTR_END,
275 };
276 
277 #define ARM64_FTR_REG(id, table) {		\
278 	.sys_id = id,				\
279 	.reg = 	&(struct arm64_ftr_reg){	\
280 		.name = #id,			\
281 		.ftr_bits = &((table)[0]),	\
282 	}}
283 
284 static const struct __ftr_reg_entry {
285 	u32			sys_id;
286 	struct arm64_ftr_reg 	*reg;
287 } arm64_ftr_regs[] = {
288 
289 	/* Op1 = 0, CRn = 0, CRm = 1 */
290 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
291 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
292 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
293 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
294 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
295 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
296 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
297 
298 	/* Op1 = 0, CRn = 0, CRm = 2 */
299 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
300 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
301 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
302 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
303 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
304 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
305 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
306 
307 	/* Op1 = 0, CRn = 0, CRm = 3 */
308 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
309 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
310 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
311 
312 	/* Op1 = 0, CRn = 0, CRm = 4 */
313 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
314 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_aa64raz),
315 
316 	/* Op1 = 0, CRn = 0, CRm = 5 */
317 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
318 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_generic),
319 
320 	/* Op1 = 0, CRn = 0, CRm = 6 */
321 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
322 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz),
323 
324 	/* Op1 = 0, CRn = 0, CRm = 7 */
325 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
326 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
327 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
328 
329 	/* Op1 = 3, CRn = 0, CRm = 0 */
330 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
331 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
332 
333 	/* Op1 = 3, CRn = 14, CRm = 0 */
334 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_generic32),
335 };
336 
337 static int search_cmp_ftr_reg(const void *id, const void *regp)
338 {
339 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
340 }
341 
342 /*
343  * get_arm64_ftr_reg - Lookup a feature register entry using its
344  * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
345  * ascending order of sys_id , we use binary search to find a matching
346  * entry.
347  *
348  * returns - Upon success,  matching ftr_reg entry for id.
349  *         - NULL on failure. It is upto the caller to decide
350  *	     the impact of a failure.
351  */
352 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
353 {
354 	const struct __ftr_reg_entry *ret;
355 
356 	ret = bsearch((const void *)(unsigned long)sys_id,
357 			arm64_ftr_regs,
358 			ARRAY_SIZE(arm64_ftr_regs),
359 			sizeof(arm64_ftr_regs[0]),
360 			search_cmp_ftr_reg);
361 	if (ret)
362 		return ret->reg;
363 	return NULL;
364 }
365 
366 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
367 			       s64 ftr_val)
368 {
369 	u64 mask = arm64_ftr_mask(ftrp);
370 
371 	reg &= ~mask;
372 	reg |= (ftr_val << ftrp->shift) & mask;
373 	return reg;
374 }
375 
376 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
377 				s64 cur)
378 {
379 	s64 ret = 0;
380 
381 	switch (ftrp->type) {
382 	case FTR_EXACT:
383 		ret = ftrp->safe_val;
384 		break;
385 	case FTR_LOWER_SAFE:
386 		ret = new < cur ? new : cur;
387 		break;
388 	case FTR_HIGHER_SAFE:
389 		ret = new > cur ? new : cur;
390 		break;
391 	default:
392 		BUG();
393 	}
394 
395 	return ret;
396 }
397 
398 static void __init sort_ftr_regs(void)
399 {
400 	int i;
401 
402 	/* Check that the array is sorted so that we can do the binary search */
403 	for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++)
404 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
405 }
406 
407 /*
408  * Initialise the CPU feature register from Boot CPU values.
409  * Also initiliases the strict_mask for the register.
410  */
411 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
412 {
413 	u64 val = 0;
414 	u64 strict_mask = ~0x0ULL;
415 	const struct arm64_ftr_bits *ftrp;
416 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
417 
418 	BUG_ON(!reg);
419 
420 	for (ftrp  = reg->ftr_bits; ftrp->width; ftrp++) {
421 		s64 ftr_new = arm64_ftr_value(ftrp, new);
422 
423 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
424 		if (!ftrp->strict)
425 			strict_mask &= ~arm64_ftr_mask(ftrp);
426 	}
427 	reg->sys_val = val;
428 	reg->strict_mask = strict_mask;
429 }
430 
431 void __init init_cpu_features(struct cpuinfo_arm64 *info)
432 {
433 	/* Before we start using the tables, make sure it is sorted */
434 	sort_ftr_regs();
435 
436 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
437 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
438 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
439 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
440 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
441 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
442 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
443 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
444 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
445 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
446 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
447 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
448 
449 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
450 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
451 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
452 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
453 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
454 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
455 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
456 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
457 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
458 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
459 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
460 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
461 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
462 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
463 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
464 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
465 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
466 	}
467 
468 }
469 
470 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
471 {
472 	const struct arm64_ftr_bits *ftrp;
473 
474 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
475 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
476 		s64 ftr_new = arm64_ftr_value(ftrp, new);
477 
478 		if (ftr_cur == ftr_new)
479 			continue;
480 		/* Find a safe value */
481 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
482 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
483 	}
484 
485 }
486 
487 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
488 {
489 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
490 
491 	BUG_ON(!regp);
492 	update_cpu_ftr_reg(regp, val);
493 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
494 		return 0;
495 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
496 			regp->name, boot, cpu, val);
497 	return 1;
498 }
499 
500 /*
501  * Update system wide CPU feature registers with the values from a
502  * non-boot CPU. Also performs SANITY checks to make sure that there
503  * aren't any insane variations from that of the boot CPU.
504  */
505 void update_cpu_features(int cpu,
506 			 struct cpuinfo_arm64 *info,
507 			 struct cpuinfo_arm64 *boot)
508 {
509 	int taint = 0;
510 
511 	/*
512 	 * The kernel can handle differing I-cache policies, but otherwise
513 	 * caches should look identical. Userspace JITs will make use of
514 	 * *minLine.
515 	 */
516 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
517 				      info->reg_ctr, boot->reg_ctr);
518 
519 	/*
520 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
521 	 * could result in too much or too little memory being zeroed if a
522 	 * process is preempted and migrated between CPUs.
523 	 */
524 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
525 				      info->reg_dczid, boot->reg_dczid);
526 
527 	/* If different, timekeeping will be broken (especially with KVM) */
528 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
529 				      info->reg_cntfrq, boot->reg_cntfrq);
530 
531 	/*
532 	 * The kernel uses self-hosted debug features and expects CPUs to
533 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
534 	 * and BRPs to be identical.
535 	 * ID_AA64DFR1 is currently RES0.
536 	 */
537 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
538 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
539 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
540 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
541 	/*
542 	 * Even in big.LITTLE, processors should be identical instruction-set
543 	 * wise.
544 	 */
545 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
546 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
547 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
548 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
549 
550 	/*
551 	 * Differing PARange support is fine as long as all peripherals and
552 	 * memory are mapped within the minimum PARange of all CPUs.
553 	 * Linux should not care about secure memory.
554 	 */
555 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
556 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
557 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
558 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
559 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
560 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
561 
562 	/*
563 	 * EL3 is not our concern.
564 	 * ID_AA64PFR1 is currently RES0.
565 	 */
566 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
567 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
568 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
569 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
570 
571 	/*
572 	 * If we have AArch32, we care about 32-bit features for compat.
573 	 * If the system doesn't support AArch32, don't update them.
574 	 */
575 	if (id_aa64pfr0_32bit_el0(read_system_reg(SYS_ID_AA64PFR0_EL1)) &&
576 		id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
577 
578 		taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
579 					info->reg_id_dfr0, boot->reg_id_dfr0);
580 		taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
581 					info->reg_id_isar0, boot->reg_id_isar0);
582 		taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
583 					info->reg_id_isar1, boot->reg_id_isar1);
584 		taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
585 					info->reg_id_isar2, boot->reg_id_isar2);
586 		taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
587 					info->reg_id_isar3, boot->reg_id_isar3);
588 		taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
589 					info->reg_id_isar4, boot->reg_id_isar4);
590 		taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
591 					info->reg_id_isar5, boot->reg_id_isar5);
592 
593 		/*
594 		 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
595 		 * ACTLR formats could differ across CPUs and therefore would have to
596 		 * be trapped for virtualization anyway.
597 		 */
598 		taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
599 					info->reg_id_mmfr0, boot->reg_id_mmfr0);
600 		taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
601 					info->reg_id_mmfr1, boot->reg_id_mmfr1);
602 		taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
603 					info->reg_id_mmfr2, boot->reg_id_mmfr2);
604 		taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
605 					info->reg_id_mmfr3, boot->reg_id_mmfr3);
606 		taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
607 					info->reg_id_pfr0, boot->reg_id_pfr0);
608 		taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
609 					info->reg_id_pfr1, boot->reg_id_pfr1);
610 		taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
611 					info->reg_mvfr0, boot->reg_mvfr0);
612 		taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
613 					info->reg_mvfr1, boot->reg_mvfr1);
614 		taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
615 					info->reg_mvfr2, boot->reg_mvfr2);
616 	}
617 
618 	/*
619 	 * Mismatched CPU features are a recipe for disaster. Don't even
620 	 * pretend to support them.
621 	 */
622 	WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC,
623 			"Unsupported CPU feature variation.\n");
624 }
625 
626 u64 read_system_reg(u32 id)
627 {
628 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
629 
630 	/* We shouldn't get a request for an unsupported register */
631 	BUG_ON(!regp);
632 	return regp->sys_val;
633 }
634 
635 /*
636  * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated.
637  * Read the system register on the current CPU
638  */
639 static u64 __raw_read_system_reg(u32 sys_id)
640 {
641 	switch (sys_id) {
642 	case SYS_ID_PFR0_EL1:		return read_cpuid(ID_PFR0_EL1);
643 	case SYS_ID_PFR1_EL1:		return read_cpuid(ID_PFR1_EL1);
644 	case SYS_ID_DFR0_EL1:		return read_cpuid(ID_DFR0_EL1);
645 	case SYS_ID_MMFR0_EL1:		return read_cpuid(ID_MMFR0_EL1);
646 	case SYS_ID_MMFR1_EL1:		return read_cpuid(ID_MMFR1_EL1);
647 	case SYS_ID_MMFR2_EL1:		return read_cpuid(ID_MMFR2_EL1);
648 	case SYS_ID_MMFR3_EL1:		return read_cpuid(ID_MMFR3_EL1);
649 	case SYS_ID_ISAR0_EL1:		return read_cpuid(ID_ISAR0_EL1);
650 	case SYS_ID_ISAR1_EL1:		return read_cpuid(ID_ISAR1_EL1);
651 	case SYS_ID_ISAR2_EL1:		return read_cpuid(ID_ISAR2_EL1);
652 	case SYS_ID_ISAR3_EL1:		return read_cpuid(ID_ISAR3_EL1);
653 	case SYS_ID_ISAR4_EL1:		return read_cpuid(ID_ISAR4_EL1);
654 	case SYS_ID_ISAR5_EL1:		return read_cpuid(ID_ISAR4_EL1);
655 	case SYS_MVFR0_EL1:		return read_cpuid(MVFR0_EL1);
656 	case SYS_MVFR1_EL1:		return read_cpuid(MVFR1_EL1);
657 	case SYS_MVFR2_EL1:		return read_cpuid(MVFR2_EL1);
658 
659 	case SYS_ID_AA64PFR0_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
660 	case SYS_ID_AA64PFR1_EL1:	return read_cpuid(ID_AA64PFR0_EL1);
661 	case SYS_ID_AA64DFR0_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
662 	case SYS_ID_AA64DFR1_EL1:	return read_cpuid(ID_AA64DFR0_EL1);
663 	case SYS_ID_AA64MMFR0_EL1:	return read_cpuid(ID_AA64MMFR0_EL1);
664 	case SYS_ID_AA64MMFR1_EL1:	return read_cpuid(ID_AA64MMFR1_EL1);
665 	case SYS_ID_AA64MMFR2_EL1:	return read_cpuid(ID_AA64MMFR2_EL1);
666 	case SYS_ID_AA64ISAR0_EL1:	return read_cpuid(ID_AA64ISAR0_EL1);
667 	case SYS_ID_AA64ISAR1_EL1:	return read_cpuid(ID_AA64ISAR1_EL1);
668 
669 	case SYS_CNTFRQ_EL0:		return read_cpuid(CNTFRQ_EL0);
670 	case SYS_CTR_EL0:		return read_cpuid(CTR_EL0);
671 	case SYS_DCZID_EL0:		return read_cpuid(DCZID_EL0);
672 	default:
673 		BUG();
674 		return 0;
675 	}
676 }
677 
678 #include <linux/irqchip/arm-gic-v3.h>
679 
680 static bool
681 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
682 {
683 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
684 
685 	return val >= entry->min_field_value;
686 }
687 
688 static bool
689 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
690 {
691 	u64 val;
692 
693 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
694 	if (scope == SCOPE_SYSTEM)
695 		val = read_system_reg(entry->sys_reg);
696 	else
697 		val = __raw_read_system_reg(entry->sys_reg);
698 
699 	return feature_matches(val, entry);
700 }
701 
702 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
703 {
704 	bool has_sre;
705 
706 	if (!has_cpuid_feature(entry, scope))
707 		return false;
708 
709 	has_sre = gic_enable_sre();
710 	if (!has_sre)
711 		pr_warn_once("%s present but disabled by higher exception level\n",
712 			     entry->desc);
713 
714 	return has_sre;
715 }
716 
717 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
718 {
719 	u32 midr = read_cpuid_id();
720 	u32 rv_min, rv_max;
721 
722 	/* Cavium ThunderX pass 1.x and 2.x */
723 	rv_min = 0;
724 	rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK;
725 
726 	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max);
727 }
728 
729 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
730 {
731 	return is_kernel_in_hyp_mode();
732 }
733 
734 static bool hyp_offset_low(const struct arm64_cpu_capabilities *entry,
735 			   int __unused)
736 {
737 	phys_addr_t idmap_addr = virt_to_phys(__hyp_idmap_text_start);
738 
739 	/*
740 	 * Activate the lower HYP offset only if:
741 	 * - the idmap doesn't clash with it,
742 	 * - the kernel is not running at EL2.
743 	 */
744 	return idmap_addr > GENMASK(VA_BITS - 2, 0) && !is_kernel_in_hyp_mode();
745 }
746 
747 static const struct arm64_cpu_capabilities arm64_features[] = {
748 	{
749 		.desc = "GIC system register CPU interface",
750 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
751 		.def_scope = SCOPE_SYSTEM,
752 		.matches = has_useable_gicv3_cpuif,
753 		.sys_reg = SYS_ID_AA64PFR0_EL1,
754 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
755 		.sign = FTR_UNSIGNED,
756 		.min_field_value = 1,
757 	},
758 #ifdef CONFIG_ARM64_PAN
759 	{
760 		.desc = "Privileged Access Never",
761 		.capability = ARM64_HAS_PAN,
762 		.def_scope = SCOPE_SYSTEM,
763 		.matches = has_cpuid_feature,
764 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
765 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
766 		.sign = FTR_UNSIGNED,
767 		.min_field_value = 1,
768 		.enable = cpu_enable_pan,
769 	},
770 #endif /* CONFIG_ARM64_PAN */
771 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
772 	{
773 		.desc = "LSE atomic instructions",
774 		.capability = ARM64_HAS_LSE_ATOMICS,
775 		.def_scope = SCOPE_SYSTEM,
776 		.matches = has_cpuid_feature,
777 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
778 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
779 		.sign = FTR_UNSIGNED,
780 		.min_field_value = 2,
781 	},
782 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
783 	{
784 		.desc = "Software prefetching using PRFM",
785 		.capability = ARM64_HAS_NO_HW_PREFETCH,
786 		.def_scope = SCOPE_SYSTEM,
787 		.matches = has_no_hw_prefetch,
788 	},
789 #ifdef CONFIG_ARM64_UAO
790 	{
791 		.desc = "User Access Override",
792 		.capability = ARM64_HAS_UAO,
793 		.def_scope = SCOPE_SYSTEM,
794 		.matches = has_cpuid_feature,
795 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
796 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
797 		.min_field_value = 1,
798 		.enable = cpu_enable_uao,
799 	},
800 #endif /* CONFIG_ARM64_UAO */
801 #ifdef CONFIG_ARM64_PAN
802 	{
803 		.capability = ARM64_ALT_PAN_NOT_UAO,
804 		.def_scope = SCOPE_SYSTEM,
805 		.matches = cpufeature_pan_not_uao,
806 	},
807 #endif /* CONFIG_ARM64_PAN */
808 	{
809 		.desc = "Virtualization Host Extensions",
810 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
811 		.def_scope = SCOPE_SYSTEM,
812 		.matches = runs_at_el2,
813 	},
814 	{
815 		.desc = "32-bit EL0 Support",
816 		.capability = ARM64_HAS_32BIT_EL0,
817 		.def_scope = SCOPE_SYSTEM,
818 		.matches = has_cpuid_feature,
819 		.sys_reg = SYS_ID_AA64PFR0_EL1,
820 		.sign = FTR_UNSIGNED,
821 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
822 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
823 	},
824 	{
825 		.desc = "Reduced HYP mapping offset",
826 		.capability = ARM64_HYP_OFFSET_LOW,
827 		.def_scope = SCOPE_SYSTEM,
828 		.matches = hyp_offset_low,
829 	},
830 	{},
831 };
832 
833 #define HWCAP_CAP(reg, field, s, min_value, type, cap)	\
834 	{							\
835 		.desc = #cap,					\
836 		.def_scope = SCOPE_SYSTEM,			\
837 		.matches = has_cpuid_feature,			\
838 		.sys_reg = reg,					\
839 		.field_pos = field,				\
840 		.sign = s,					\
841 		.min_field_value = min_value,			\
842 		.hwcap_type = type,				\
843 		.hwcap = cap,					\
844 	}
845 
846 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
847 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_PMULL),
848 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES),
849 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1),
850 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2),
851 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32),
852 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
853 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
854 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP),
855 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
856 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP),
857 	{},
858 };
859 
860 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
861 #ifdef CONFIG_COMPAT
862 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
863 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
864 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
865 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
866 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
867 #endif
868 	{},
869 };
870 
871 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
872 {
873 	switch (cap->hwcap_type) {
874 	case CAP_HWCAP:
875 		elf_hwcap |= cap->hwcap;
876 		break;
877 #ifdef CONFIG_COMPAT
878 	case CAP_COMPAT_HWCAP:
879 		compat_elf_hwcap |= (u32)cap->hwcap;
880 		break;
881 	case CAP_COMPAT_HWCAP2:
882 		compat_elf_hwcap2 |= (u32)cap->hwcap;
883 		break;
884 #endif
885 	default:
886 		WARN_ON(1);
887 		break;
888 	}
889 }
890 
891 /* Check if we have a particular HWCAP enabled */
892 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
893 {
894 	bool rc;
895 
896 	switch (cap->hwcap_type) {
897 	case CAP_HWCAP:
898 		rc = (elf_hwcap & cap->hwcap) != 0;
899 		break;
900 #ifdef CONFIG_COMPAT
901 	case CAP_COMPAT_HWCAP:
902 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
903 		break;
904 	case CAP_COMPAT_HWCAP2:
905 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
906 		break;
907 #endif
908 	default:
909 		WARN_ON(1);
910 		rc = false;
911 	}
912 
913 	return rc;
914 }
915 
916 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
917 {
918 	for (; hwcaps->matches; hwcaps++)
919 		if (hwcaps->matches(hwcaps, hwcaps->def_scope))
920 			cap_set_elf_hwcap(hwcaps);
921 }
922 
923 void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
924 			    const char *info)
925 {
926 	for (; caps->matches; caps++) {
927 		if (!caps->matches(caps, caps->def_scope))
928 			continue;
929 
930 		if (!cpus_have_cap(caps->capability) && caps->desc)
931 			pr_info("%s %s\n", info, caps->desc);
932 		cpus_set_cap(caps->capability);
933 	}
934 }
935 
936 /*
937  * Run through the enabled capabilities and enable() it on all active
938  * CPUs
939  */
940 void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
941 {
942 	for (; caps->matches; caps++)
943 		if (caps->enable && cpus_have_cap(caps->capability))
944 			on_each_cpu(caps->enable, NULL, true);
945 }
946 
947 /*
948  * Flag to indicate if we have computed the system wide
949  * capabilities based on the boot time active CPUs. This
950  * will be used to determine if a new booting CPU should
951  * go through the verification process to make sure that it
952  * supports the system capabilities, without using a hotplug
953  * notifier.
954  */
955 static bool sys_caps_initialised;
956 
957 static inline void set_sys_caps_initialised(void)
958 {
959 	sys_caps_initialised = true;
960 }
961 
962 /*
963  * Check for CPU features that are used in early boot
964  * based on the Boot CPU value.
965  */
966 static void check_early_cpu_features(void)
967 {
968 	verify_cpu_run_el();
969 	verify_cpu_asid_bits();
970 }
971 
972 static void
973 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
974 {
975 
976 	for (; caps->matches; caps++)
977 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
978 			pr_crit("CPU%d: missing HWCAP: %s\n",
979 					smp_processor_id(), caps->desc);
980 			cpu_die_early();
981 		}
982 }
983 
984 static void
985 verify_local_cpu_features(const struct arm64_cpu_capabilities *caps)
986 {
987 	for (; caps->matches; caps++) {
988 		if (!cpus_have_cap(caps->capability))
989 			continue;
990 		/*
991 		 * If the new CPU misses an advertised feature, we cannot proceed
992 		 * further, park the cpu.
993 		 */
994 		if (!caps->matches(caps, SCOPE_LOCAL_CPU)) {
995 			pr_crit("CPU%d: missing feature: %s\n",
996 					smp_processor_id(), caps->desc);
997 			cpu_die_early();
998 		}
999 		if (caps->enable)
1000 			caps->enable(NULL);
1001 	}
1002 }
1003 
1004 /*
1005  * Run through the enabled system capabilities and enable() it on this CPU.
1006  * The capabilities were decided based on the available CPUs at the boot time.
1007  * Any new CPU should match the system wide status of the capability. If the
1008  * new CPU doesn't have a capability which the system now has enabled, we
1009  * cannot do anything to fix it up and could cause unexpected failures. So
1010  * we park the CPU.
1011  */
1012 static void verify_local_cpu_capabilities(void)
1013 {
1014 	verify_local_cpu_errata_workarounds();
1015 	verify_local_cpu_features(arm64_features);
1016 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
1017 	if (system_supports_32bit_el0())
1018 		verify_local_elf_hwcaps(compat_elf_hwcaps);
1019 }
1020 
1021 void check_local_cpu_capabilities(void)
1022 {
1023 	/*
1024 	 * All secondary CPUs should conform to the early CPU features
1025 	 * in use by the kernel based on boot CPU.
1026 	 */
1027 	check_early_cpu_features();
1028 
1029 	/*
1030 	 * If we haven't finalised the system capabilities, this CPU gets
1031 	 * a chance to update the errata work arounds.
1032 	 * Otherwise, this CPU should verify that it has all the system
1033 	 * advertised capabilities.
1034 	 */
1035 	if (!sys_caps_initialised)
1036 		update_cpu_errata_workarounds();
1037 	else
1038 		verify_local_cpu_capabilities();
1039 }
1040 
1041 static void __init setup_feature_capabilities(void)
1042 {
1043 	update_cpu_capabilities(arm64_features, "detected feature:");
1044 	enable_cpu_capabilities(arm64_features);
1045 }
1046 
1047 /*
1048  * Check if the current CPU has a given feature capability.
1049  * Should be called from non-preemptible context.
1050  */
1051 bool this_cpu_has_cap(unsigned int cap)
1052 {
1053 	const struct arm64_cpu_capabilities *caps;
1054 
1055 	if (WARN_ON(preemptible()))
1056 		return false;
1057 
1058 	for (caps = arm64_features; caps->desc; caps++)
1059 		if (caps->capability == cap && caps->matches)
1060 			return caps->matches(caps, SCOPE_LOCAL_CPU);
1061 
1062 	return false;
1063 }
1064 
1065 void __init setup_cpu_features(void)
1066 {
1067 	u32 cwg;
1068 	int cls;
1069 
1070 	/* Set the CPU feature capabilies */
1071 	setup_feature_capabilities();
1072 	enable_errata_workarounds();
1073 	setup_elf_hwcaps(arm64_elf_hwcaps);
1074 
1075 	if (system_supports_32bit_el0())
1076 		setup_elf_hwcaps(compat_elf_hwcaps);
1077 
1078 	/* Advertise that we have computed the system capabilities */
1079 	set_sys_caps_initialised();
1080 
1081 	/*
1082 	 * Check for sane CTR_EL0.CWG value.
1083 	 */
1084 	cwg = cache_type_cwg();
1085 	cls = cache_line_size();
1086 	if (!cwg)
1087 		pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
1088 			cls);
1089 	if (L1_CACHE_BYTES < cls)
1090 		pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
1091 			L1_CACHE_BYTES, cls);
1092 }
1093 
1094 static bool __maybe_unused
1095 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
1096 {
1097 	return (cpus_have_cap(ARM64_HAS_PAN) && !cpus_have_cap(ARM64_HAS_UAO));
1098 }
1099