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/processor.h>
28 #include <asm/sysreg.h>
29
30 unsigned long elf_hwcap __read_mostly;
31 EXPORT_SYMBOL_GPL(elf_hwcap);
32
33 #ifdef CONFIG_COMPAT
34 #define COMPAT_ELF_HWCAP_DEFAULT \
35 (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
36 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
37 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
38 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
39 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
40 COMPAT_HWCAP_LPAE)
41 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
42 unsigned int compat_elf_hwcap2 __read_mostly;
43 #endif
44
45 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
46 EXPORT_SYMBOL(cpu_hwcaps);
47
48 #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
49 { \
50 .sign = SIGNED, \
51 .strict = STRICT, \
52 .type = TYPE, \
53 .shift = SHIFT, \
54 .width = WIDTH, \
55 .safe_val = SAFE_VAL, \
56 }
57
58 /* Define a feature with signed values */
59 #define ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
60 __ARM64_FTR_BITS(FTR_SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
61
62 /* Define a feature with unsigned value */
63 #define U_ARM64_FTR_BITS(STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
64 __ARM64_FTR_BITS(FTR_UNSIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
65
66 #define ARM64_FTR_END \
67 { \
68 .width = 0, \
69 }
70
71 /* meta feature for alternatives */
72 static bool __maybe_unused
73 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry);
74
75 static struct arm64_ftr_bits ftr_id_aa64isar0[] = {
76 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
77 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
78 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0),
79 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
80 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
81 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
82 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
83 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0), /* RAZ */
84 ARM64_FTR_END,
85 };
86
87 static struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
88 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
89 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0),
90 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_GIC_SHIFT, 4, 0),
91 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
92 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
93 /* Linux doesn't care about the EL3 */
94 ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64PFR0_EL3_SHIFT, 4, 0),
95 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL2_SHIFT, 4, 0),
96 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
97 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
98 ARM64_FTR_END,
99 };
100
101 static struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
102 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
103 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
104 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
105 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
106 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
107 /* Linux shouldn't care about secure memory */
108 ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
109 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
110 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
111 /*
112 * Differing PARange is fine as long as all peripherals and memory are mapped
113 * within the minimum PARange of all CPUs
114 */
115 U_ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
116 ARM64_FTR_END,
117 };
118
119 static struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
120 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
121 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
122 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
123 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
124 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
125 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
126 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
127 ARM64_FTR_END,
128 };
129
130 static struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
131 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
132 ARM64_FTR_END,
133 };
134
135 static struct arm64_ftr_bits ftr_ctr[] = {
136 U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RAO */
137 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 3, 0),
138 U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */
139 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), /* ERG */
140 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */
141 /*
142 * Linux can handle differing I-cache policies. Userspace JITs will
143 * make use of *minLine
144 */
145 U_ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, 0), /* L1Ip */
146 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 10, 0), /* RAZ */
147 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* IminLine */
148 ARM64_FTR_END,
149 };
150
151 static struct arm64_ftr_bits ftr_id_mmfr0[] = {
152 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 4, 0), /* InnerShr */
153 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 24, 4, 0), /* FCSE */
154 ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0), /* AuxReg */
155 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 4, 0), /* TCM */
156 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0), /* ShareLvl */
157 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0), /* OuterShr */
158 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0), /* PMSA */
159 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0), /* VMSA */
160 ARM64_FTR_END,
161 };
162
163 static struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
164 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 32, 32, 0),
165 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
166 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
167 U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
168 U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
169 U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
170 U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
171 ARM64_FTR_END,
172 };
173
174 static struct arm64_ftr_bits ftr_mvfr2[] = {
175 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0), /* RAZ */
176 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0), /* FPMisc */
177 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0), /* SIMDMisc */
178 ARM64_FTR_END,
179 };
180
181 static struct arm64_ftr_bits ftr_dczid[] = {
182 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 5, 27, 0), /* RAZ */
183 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 1, 1), /* DZP */
184 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* BS */
185 ARM64_FTR_END,
186 };
187
188
189 static struct arm64_ftr_bits ftr_id_isar5[] = {
190 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_RDM_SHIFT, 4, 0),
191 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 20, 4, 0), /* RAZ */
192 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_CRC32_SHIFT, 4, 0),
193 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA2_SHIFT, 4, 0),
194 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA1_SHIFT, 4, 0),
195 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_AES_SHIFT, 4, 0),
196 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_ISAR5_SEVL_SHIFT, 4, 0),
197 ARM64_FTR_END,
198 };
199
200 static struct arm64_ftr_bits ftr_id_mmfr4[] = {
201 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 24, 0), /* RAZ */
202 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0), /* ac2 */
203 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0), /* RAZ */
204 ARM64_FTR_END,
205 };
206
207 static struct arm64_ftr_bits ftr_id_pfr0[] = {
208 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 16, 16, 0), /* RAZ */
209 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 12, 4, 0), /* State3 */
210 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 8, 4, 0), /* State2 */
211 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 4, 0), /* State1 */
212 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 4, 0), /* State0 */
213 ARM64_FTR_END,
214 };
215
216 /*
217 * Common ftr bits for a 32bit register with all hidden, strict
218 * attributes, with 4bit feature fields and a default safe value of
219 * 0. Covers the following 32bit registers:
220 * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
221 */
222 static struct arm64_ftr_bits ftr_generic_32bits[] = {
223 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
224 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
225 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
226 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
227 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
228 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
229 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
230 ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
231 ARM64_FTR_END,
232 };
233
234 static struct arm64_ftr_bits ftr_generic[] = {
235 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
236 ARM64_FTR_END,
237 };
238
239 static struct arm64_ftr_bits ftr_generic32[] = {
240 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 32, 0),
241 ARM64_FTR_END,
242 };
243
244 static struct arm64_ftr_bits ftr_aa64raz[] = {
245 ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 0, 64, 0),
246 ARM64_FTR_END,
247 };
248
249 #define ARM64_FTR_REG(id, table) \
250 { \
251 .sys_id = id, \
252 .name = #id, \
253 .ftr_bits = &((table)[0]), \
254 }
255
256 static struct arm64_ftr_reg arm64_ftr_regs[] = {
257
258 /* Op1 = 0, CRn = 0, CRm = 1 */
259 ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
260 ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
261 ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_generic_32bits),
262 ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
263 ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
264 ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
265 ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
266
267 /* Op1 = 0, CRn = 0, CRm = 2 */
268 ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
269 ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
270 ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
271 ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
272 ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
273 ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
274 ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
275
276 /* Op1 = 0, CRn = 0, CRm = 3 */
277 ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
278 ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
279 ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
280
281 /* Op1 = 0, CRn = 0, CRm = 4 */
282 ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
283 ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_aa64raz),
284
285 /* Op1 = 0, CRn = 0, CRm = 5 */
286 ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
287 ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_generic),
288
289 /* Op1 = 0, CRn = 0, CRm = 6 */
290 ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
291 ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz),
292
293 /* Op1 = 0, CRn = 0, CRm = 7 */
294 ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
295 ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
296 ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
297
298 /* Op1 = 3, CRn = 0, CRm = 0 */
299 ARM64_FTR_REG(SYS_CTR_EL0, ftr_ctr),
300 ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
301
302 /* Op1 = 3, CRn = 14, CRm = 0 */
303 ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_generic32),
304 };
305
search_cmp_ftr_reg(const void * id,const void * regp)306 static int search_cmp_ftr_reg(const void *id, const void *regp)
307 {
308 return (int)(unsigned long)id - (int)((const struct arm64_ftr_reg *)regp)->sys_id;
309 }
310
311 /*
312 * get_arm64_ftr_reg - Lookup a feature register entry using its
313 * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
314 * ascending order of sys_id , we use binary search to find a matching
315 * entry.
316 *
317 * returns - Upon success, matching ftr_reg entry for id.
318 * - NULL on failure. It is upto the caller to decide
319 * the impact of a failure.
320 */
get_arm64_ftr_reg(u32 sys_id)321 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
322 {
323 return bsearch((const void *)(unsigned long)sys_id,
324 arm64_ftr_regs,
325 ARRAY_SIZE(arm64_ftr_regs),
326 sizeof(arm64_ftr_regs[0]),
327 search_cmp_ftr_reg);
328 }
329
arm64_ftr_set_value(struct arm64_ftr_bits * ftrp,s64 reg,s64 ftr_val)330 static u64 arm64_ftr_set_value(struct arm64_ftr_bits *ftrp, s64 reg, s64 ftr_val)
331 {
332 u64 mask = arm64_ftr_mask(ftrp);
333
334 reg &= ~mask;
335 reg |= (ftr_val << ftrp->shift) & mask;
336 return reg;
337 }
338
arm64_ftr_safe_value(struct arm64_ftr_bits * ftrp,s64 new,s64 cur)339 static s64 arm64_ftr_safe_value(struct arm64_ftr_bits *ftrp, s64 new, s64 cur)
340 {
341 s64 ret = 0;
342
343 switch (ftrp->type) {
344 case FTR_EXACT:
345 ret = ftrp->safe_val;
346 break;
347 case FTR_LOWER_SAFE:
348 ret = new < cur ? new : cur;
349 break;
350 case FTR_HIGHER_SAFE:
351 ret = new > cur ? new : cur;
352 break;
353 default:
354 BUG();
355 }
356
357 return ret;
358 }
359
sort_cmp_ftr_regs(const void * a,const void * b)360 static int __init sort_cmp_ftr_regs(const void *a, const void *b)
361 {
362 return ((const struct arm64_ftr_reg *)a)->sys_id -
363 ((const struct arm64_ftr_reg *)b)->sys_id;
364 }
365
swap_ftr_regs(void * a,void * b,int size)366 static void __init swap_ftr_regs(void *a, void *b, int size)
367 {
368 struct arm64_ftr_reg tmp = *(struct arm64_ftr_reg *)a;
369 *(struct arm64_ftr_reg *)a = *(struct arm64_ftr_reg *)b;
370 *(struct arm64_ftr_reg *)b = tmp;
371 }
372
sort_ftr_regs(void)373 static void __init sort_ftr_regs(void)
374 {
375 /* Keep the array sorted so that we can do the binary search */
376 sort(arm64_ftr_regs,
377 ARRAY_SIZE(arm64_ftr_regs),
378 sizeof(arm64_ftr_regs[0]),
379 sort_cmp_ftr_regs,
380 swap_ftr_regs);
381 }
382
383 /*
384 * Initialise the CPU feature register from Boot CPU values.
385 * Also initiliases the strict_mask for the register.
386 */
init_cpu_ftr_reg(u32 sys_reg,u64 new)387 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
388 {
389 u64 val = 0;
390 u64 strict_mask = ~0x0ULL;
391 struct arm64_ftr_bits *ftrp;
392 struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
393
394 BUG_ON(!reg);
395
396 for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
397 s64 ftr_new = arm64_ftr_value(ftrp, new);
398
399 val = arm64_ftr_set_value(ftrp, val, ftr_new);
400 if (!ftrp->strict)
401 strict_mask &= ~arm64_ftr_mask(ftrp);
402 }
403 reg->sys_val = val;
404 reg->strict_mask = strict_mask;
405 }
406
init_cpu_features(struct cpuinfo_arm64 * info)407 void __init init_cpu_features(struct cpuinfo_arm64 *info)
408 {
409 /* Before we start using the tables, make sure it is sorted */
410 sort_ftr_regs();
411
412 init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
413 init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
414 init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
415 init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
416 init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
417 init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
418 init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
419 init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
420 init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
421 init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
422 init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
423 init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
424 init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
425 init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
426 init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
427 init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
428 init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
429 init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
430 init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
431 init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
432 init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
433 init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
434 init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
435 init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
436 init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
437 init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
438 init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
439 init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
440 }
441
update_cpu_ftr_reg(struct arm64_ftr_reg * reg,u64 new)442 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
443 {
444 struct arm64_ftr_bits *ftrp;
445
446 for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
447 s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
448 s64 ftr_new = arm64_ftr_value(ftrp, new);
449
450 if (ftr_cur == ftr_new)
451 continue;
452 /* Find a safe value */
453 ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
454 reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
455 }
456
457 }
458
check_update_ftr_reg(u32 sys_id,int cpu,u64 val,u64 boot)459 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
460 {
461 struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
462
463 BUG_ON(!regp);
464 update_cpu_ftr_reg(regp, val);
465 if ((boot & regp->strict_mask) == (val & regp->strict_mask))
466 return 0;
467 pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
468 regp->name, boot, cpu, val);
469 return 1;
470 }
471
472 /*
473 * Update system wide CPU feature registers with the values from a
474 * non-boot CPU. Also performs SANITY checks to make sure that there
475 * aren't any insane variations from that of the boot CPU.
476 */
update_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)477 void update_cpu_features(int cpu,
478 struct cpuinfo_arm64 *info,
479 struct cpuinfo_arm64 *boot)
480 {
481 int taint = 0;
482
483 /*
484 * The kernel can handle differing I-cache policies, but otherwise
485 * caches should look identical. Userspace JITs will make use of
486 * *minLine.
487 */
488 taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
489 info->reg_ctr, boot->reg_ctr);
490
491 /*
492 * Userspace may perform DC ZVA instructions. Mismatched block sizes
493 * could result in too much or too little memory being zeroed if a
494 * process is preempted and migrated between CPUs.
495 */
496 taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
497 info->reg_dczid, boot->reg_dczid);
498
499 /* If different, timekeeping will be broken (especially with KVM) */
500 taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
501 info->reg_cntfrq, boot->reg_cntfrq);
502
503 /*
504 * The kernel uses self-hosted debug features and expects CPUs to
505 * support identical debug features. We presently need CTX_CMPs, WRPs,
506 * and BRPs to be identical.
507 * ID_AA64DFR1 is currently RES0.
508 */
509 taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
510 info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
511 taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
512 info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
513 /*
514 * Even in big.LITTLE, processors should be identical instruction-set
515 * wise.
516 */
517 taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
518 info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
519 taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
520 info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
521
522 /*
523 * Differing PARange support is fine as long as all peripherals and
524 * memory are mapped within the minimum PARange of all CPUs.
525 * Linux should not care about secure memory.
526 */
527 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
528 info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
529 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
530 info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
531 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
532 info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
533
534 /*
535 * EL3 is not our concern.
536 * ID_AA64PFR1 is currently RES0.
537 */
538 taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
539 info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
540 taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
541 info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
542
543 /*
544 * If we have AArch32, we care about 32-bit features for compat. These
545 * registers should be RES0 otherwise.
546 */
547 taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
548 info->reg_id_dfr0, boot->reg_id_dfr0);
549 taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
550 info->reg_id_isar0, boot->reg_id_isar0);
551 taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
552 info->reg_id_isar1, boot->reg_id_isar1);
553 taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
554 info->reg_id_isar2, boot->reg_id_isar2);
555 taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
556 info->reg_id_isar3, boot->reg_id_isar3);
557 taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
558 info->reg_id_isar4, boot->reg_id_isar4);
559 taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
560 info->reg_id_isar5, boot->reg_id_isar5);
561
562 /*
563 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
564 * ACTLR formats could differ across CPUs and therefore would have to
565 * be trapped for virtualization anyway.
566 */
567 taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
568 info->reg_id_mmfr0, boot->reg_id_mmfr0);
569 taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
570 info->reg_id_mmfr1, boot->reg_id_mmfr1);
571 taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
572 info->reg_id_mmfr2, boot->reg_id_mmfr2);
573 taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
574 info->reg_id_mmfr3, boot->reg_id_mmfr3);
575 taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
576 info->reg_id_pfr0, boot->reg_id_pfr0);
577 taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
578 info->reg_id_pfr1, boot->reg_id_pfr1);
579 taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
580 info->reg_mvfr0, boot->reg_mvfr0);
581 taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
582 info->reg_mvfr1, boot->reg_mvfr1);
583 taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
584 info->reg_mvfr2, boot->reg_mvfr2);
585
586 /*
587 * Mismatched CPU features are a recipe for disaster. Don't even
588 * pretend to support them.
589 */
590 WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC,
591 "Unsupported CPU feature variation.\n");
592 }
593
read_system_reg(u32 id)594 u64 read_system_reg(u32 id)
595 {
596 struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
597
598 /* We shouldn't get a request for an unsupported register */
599 BUG_ON(!regp);
600 return regp->sys_val;
601 }
602
603 static bool
feature_matches(u64 reg,const struct arm64_cpu_capabilities * entry)604 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
605 {
606 int val = cpuid_feature_extract_field(reg, entry->field_pos);
607
608 return val >= entry->min_field_value;
609 }
610
611 static bool
has_cpuid_feature(const struct arm64_cpu_capabilities * entry)612 has_cpuid_feature(const struct arm64_cpu_capabilities *entry)
613 {
614 u64 val;
615
616 val = read_system_reg(entry->sys_reg);
617 return feature_matches(val, entry);
618 }
619
620 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
621 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
622
unmap_kernel_at_el0(const struct arm64_cpu_capabilities * entry)623 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry)
624 {
625 /* Forced on command line? */
626 if (__kpti_forced) {
627 pr_info_once("kernel page table isolation forced %s by command line option\n",
628 __kpti_forced > 0 ? "ON" : "OFF");
629 return __kpti_forced > 0;
630 }
631
632 /* Useful for KASLR robustness */
633 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
634 return true;
635
636 return false;
637 }
638
parse_kpti(char * str)639 static int __init parse_kpti(char *str)
640 {
641 bool enabled;
642 int ret = strtobool(str, &enabled);
643
644 if (ret)
645 return ret;
646
647 __kpti_forced = enabled ? 1 : -1;
648 return 0;
649 }
650 __setup("kpti=", parse_kpti);
651 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
652
653 static const struct arm64_cpu_capabilities arm64_features[] = {
654 {
655 .desc = "GIC system register CPU interface",
656 .capability = ARM64_HAS_SYSREG_GIC_CPUIF,
657 .matches = has_cpuid_feature,
658 .sys_reg = SYS_ID_AA64PFR0_EL1,
659 .field_pos = ID_AA64PFR0_GIC_SHIFT,
660 .min_field_value = 1,
661 },
662 #ifdef CONFIG_ARM64_PAN
663 {
664 .desc = "Privileged Access Never",
665 .capability = ARM64_HAS_PAN,
666 .matches = has_cpuid_feature,
667 .sys_reg = SYS_ID_AA64MMFR1_EL1,
668 .field_pos = ID_AA64MMFR1_PAN_SHIFT,
669 .min_field_value = 1,
670 .enable = cpu_enable_pan,
671 },
672 #endif /* CONFIG_ARM64_PAN */
673 #ifdef CONFIG_ARM64_UAO
674 {
675 .desc = "User Access Override",
676 .capability = ARM64_HAS_UAO,
677 .matches = has_cpuid_feature,
678 .sys_reg = SYS_ID_AA64MMFR2_EL1,
679 .field_pos = ID_AA64MMFR2_UAO_SHIFT,
680 .min_field_value = 1,
681 .enable = cpu_enable_uao,
682 },
683 #endif /* CONFIG_ARM64_UAO */
684 #ifdef CONFIG_ARM64_PAN
685 {
686 .capability = ARM64_ALT_PAN_NOT_UAO,
687 .matches = cpufeature_pan_not_uao,
688 },
689 #endif /* CONFIG_ARM64_PAN */
690 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
691 {
692 .capability = ARM64_UNMAP_KERNEL_AT_EL0,
693 .matches = unmap_kernel_at_el0,
694 },
695 #endif
696 {},
697 };
698
699 #define HWCAP_CAP(reg, field, min_value, type, cap) \
700 { \
701 .desc = #cap, \
702 .matches = has_cpuid_feature, \
703 .sys_reg = reg, \
704 .field_pos = field, \
705 .min_field_value = min_value, \
706 .hwcap_type = type, \
707 .hwcap = cap, \
708 }
709
710 static const struct arm64_cpu_capabilities arm64_hwcaps[] = {
711 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, 2, CAP_HWCAP, HWCAP_PMULL),
712 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, 1, CAP_HWCAP, HWCAP_AES),
713 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, 1, CAP_HWCAP, HWCAP_SHA1),
714 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, 1, CAP_HWCAP, HWCAP_SHA2),
715 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, 1, CAP_HWCAP, HWCAP_CRC32),
716 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, 0, CAP_HWCAP, HWCAP_FP),
717 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, 0, CAP_HWCAP, HWCAP_ASIMD),
718 #ifdef CONFIG_COMPAT
719 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
720 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
721 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
722 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
723 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
724 #endif
725 {},
726 };
727
cap_set_hwcap(const struct arm64_cpu_capabilities * cap)728 static void __init cap_set_hwcap(const struct arm64_cpu_capabilities *cap)
729 {
730 switch (cap->hwcap_type) {
731 case CAP_HWCAP:
732 elf_hwcap |= cap->hwcap;
733 break;
734 #ifdef CONFIG_COMPAT
735 case CAP_COMPAT_HWCAP:
736 compat_elf_hwcap |= (u32)cap->hwcap;
737 break;
738 case CAP_COMPAT_HWCAP2:
739 compat_elf_hwcap2 |= (u32)cap->hwcap;
740 break;
741 #endif
742 default:
743 WARN_ON(1);
744 break;
745 }
746 }
747
748 /* Check if we have a particular HWCAP enabled */
cpus_have_hwcap(const struct arm64_cpu_capabilities * cap)749 static bool __maybe_unused cpus_have_hwcap(const struct arm64_cpu_capabilities *cap)
750 {
751 bool rc;
752
753 switch (cap->hwcap_type) {
754 case CAP_HWCAP:
755 rc = (elf_hwcap & cap->hwcap) != 0;
756 break;
757 #ifdef CONFIG_COMPAT
758 case CAP_COMPAT_HWCAP:
759 rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
760 break;
761 case CAP_COMPAT_HWCAP2:
762 rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
763 break;
764 #endif
765 default:
766 WARN_ON(1);
767 rc = false;
768 }
769
770 return rc;
771 }
772
setup_cpu_hwcaps(void)773 static void __init setup_cpu_hwcaps(void)
774 {
775 int i;
776 const struct arm64_cpu_capabilities *hwcaps = arm64_hwcaps;
777
778 for (i = 0; hwcaps[i].matches; i++)
779 if (hwcaps[i].matches(&hwcaps[i]))
780 cap_set_hwcap(&hwcaps[i]);
781 }
782
update_cpu_capabilities(const struct arm64_cpu_capabilities * caps,const char * info)783 void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
784 const char *info)
785 {
786 int i;
787
788 for (i = 0; caps[i].matches; i++) {
789 if (!caps[i].matches(&caps[i]))
790 continue;
791
792 if (!cpus_have_cap(caps[i].capability) && caps[i].desc)
793 pr_info("%s %s\n", info, caps[i].desc);
794 cpus_set_cap(caps[i].capability);
795 }
796 }
797
798 /*
799 * Run through the enabled capabilities and enable() it on all active
800 * CPUs
801 */
802 static void __init
enable_cpu_capabilities(const struct arm64_cpu_capabilities * caps)803 enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
804 {
805 int i;
806
807 for (i = 0; caps[i].matches; i++)
808 if (caps[i].enable && cpus_have_cap(caps[i].capability))
809 on_each_cpu(caps[i].enable, NULL, true);
810 }
811
812 #ifdef CONFIG_HOTPLUG_CPU
813
814 /*
815 * Flag to indicate if we have computed the system wide
816 * capabilities based on the boot time active CPUs. This
817 * will be used to determine if a new booting CPU should
818 * go through the verification process to make sure that it
819 * supports the system capabilities, without using a hotplug
820 * notifier.
821 */
822 static bool sys_caps_initialised;
823
set_sys_caps_initialised(void)824 static inline void set_sys_caps_initialised(void)
825 {
826 sys_caps_initialised = true;
827 }
828
829 /*
830 * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated.
831 */
__raw_read_system_reg(u32 sys_id)832 static u64 __raw_read_system_reg(u32 sys_id)
833 {
834 switch (sys_id) {
835 case SYS_ID_PFR0_EL1: return read_cpuid(SYS_ID_PFR0_EL1);
836 case SYS_ID_PFR1_EL1: return read_cpuid(SYS_ID_PFR1_EL1);
837 case SYS_ID_DFR0_EL1: return read_cpuid(SYS_ID_DFR0_EL1);
838 case SYS_ID_MMFR0_EL1: return read_cpuid(SYS_ID_MMFR0_EL1);
839 case SYS_ID_MMFR1_EL1: return read_cpuid(SYS_ID_MMFR1_EL1);
840 case SYS_ID_MMFR2_EL1: return read_cpuid(SYS_ID_MMFR2_EL1);
841 case SYS_ID_MMFR3_EL1: return read_cpuid(SYS_ID_MMFR3_EL1);
842 case SYS_ID_ISAR0_EL1: return read_cpuid(SYS_ID_ISAR0_EL1);
843 case SYS_ID_ISAR1_EL1: return read_cpuid(SYS_ID_ISAR1_EL1);
844 case SYS_ID_ISAR2_EL1: return read_cpuid(SYS_ID_ISAR2_EL1);
845 case SYS_ID_ISAR3_EL1: return read_cpuid(SYS_ID_ISAR3_EL1);
846 case SYS_ID_ISAR4_EL1: return read_cpuid(SYS_ID_ISAR4_EL1);
847 case SYS_ID_ISAR5_EL1: return read_cpuid(SYS_ID_ISAR4_EL1);
848 case SYS_MVFR0_EL1: return read_cpuid(SYS_MVFR0_EL1);
849 case SYS_MVFR1_EL1: return read_cpuid(SYS_MVFR1_EL1);
850 case SYS_MVFR2_EL1: return read_cpuid(SYS_MVFR2_EL1);
851
852 case SYS_ID_AA64PFR0_EL1: return read_cpuid(SYS_ID_AA64PFR0_EL1);
853 case SYS_ID_AA64PFR1_EL1: return read_cpuid(SYS_ID_AA64PFR0_EL1);
854 case SYS_ID_AA64DFR0_EL1: return read_cpuid(SYS_ID_AA64DFR0_EL1);
855 case SYS_ID_AA64DFR1_EL1: return read_cpuid(SYS_ID_AA64DFR0_EL1);
856 case SYS_ID_AA64MMFR0_EL1: return read_cpuid(SYS_ID_AA64MMFR0_EL1);
857 case SYS_ID_AA64MMFR1_EL1: return read_cpuid(SYS_ID_AA64MMFR1_EL1);
858 case SYS_ID_AA64MMFR2_EL1: return read_cpuid(SYS_ID_AA64MMFR2_EL1);
859 case SYS_ID_AA64ISAR0_EL1: return read_cpuid(SYS_ID_AA64ISAR0_EL1);
860 case SYS_ID_AA64ISAR1_EL1: return read_cpuid(SYS_ID_AA64ISAR1_EL1);
861
862 case SYS_CNTFRQ_EL0: return read_cpuid(SYS_CNTFRQ_EL0);
863 case SYS_CTR_EL0: return read_cpuid(SYS_CTR_EL0);
864 case SYS_DCZID_EL0: return read_cpuid(SYS_DCZID_EL0);
865 default:
866 BUG();
867 return 0;
868 }
869 }
870
871 /*
872 * Park the CPU which doesn't have the capability as advertised
873 * by the system.
874 */
fail_incapable_cpu(char * cap_type,const struct arm64_cpu_capabilities * cap)875 static void fail_incapable_cpu(char *cap_type,
876 const struct arm64_cpu_capabilities *cap)
877 {
878 int cpu = smp_processor_id();
879
880 pr_crit("CPU%d: missing %s : %s\n", cpu, cap_type, cap->desc);
881 /* Mark this CPU absent */
882 set_cpu_present(cpu, 0);
883
884 /* Check if we can park ourselves */
885 if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die)
886 cpu_ops[cpu]->cpu_die(cpu);
887 asm(
888 "1: wfe\n"
889 " wfi\n"
890 " b 1b");
891 }
892
893 /*
894 * Run through the enabled system capabilities and enable() it on this CPU.
895 * The capabilities were decided based on the available CPUs at the boot time.
896 * Any new CPU should match the system wide status of the capability. If the
897 * new CPU doesn't have a capability which the system now has enabled, we
898 * cannot do anything to fix it up and could cause unexpected failures. So
899 * we park the CPU.
900 */
verify_local_cpu_capabilities(void)901 void verify_local_cpu_capabilities(void)
902 {
903 int i;
904 const struct arm64_cpu_capabilities *caps;
905
906 /*
907 * If we haven't computed the system capabilities, there is nothing
908 * to verify.
909 */
910 if (!sys_caps_initialised)
911 return;
912
913 caps = arm64_features;
914 for (i = 0; caps[i].matches; i++) {
915 if (!cpus_have_cap(caps[i].capability) || !caps[i].sys_reg)
916 continue;
917 /*
918 * If the new CPU misses an advertised feature, we cannot proceed
919 * further, park the cpu.
920 */
921 if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i]))
922 fail_incapable_cpu("arm64_features", &caps[i]);
923 if (caps[i].enable)
924 caps[i].enable(NULL);
925 }
926
927 for (i = 0, caps = arm64_hwcaps; caps[i].matches; i++) {
928 if (!cpus_have_hwcap(&caps[i]))
929 continue;
930 if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i]))
931 fail_incapable_cpu("arm64_hwcaps", &caps[i]);
932 }
933 }
934
935 #else /* !CONFIG_HOTPLUG_CPU */
936
set_sys_caps_initialised(void)937 static inline void set_sys_caps_initialised(void)
938 {
939 }
940
941 #endif /* CONFIG_HOTPLUG_CPU */
942
setup_feature_capabilities(void)943 static void __init setup_feature_capabilities(void)
944 {
945 update_cpu_capabilities(arm64_features, "detected feature:");
946 enable_cpu_capabilities(arm64_features);
947 }
948
setup_cpu_features(void)949 void __init setup_cpu_features(void)
950 {
951 u32 cwg;
952 int cls;
953
954 /* Set the CPU feature capabilies */
955 setup_feature_capabilities();
956 setup_cpu_hwcaps();
957
958 /* Advertise that we have computed the system capabilities */
959 set_sys_caps_initialised();
960
961 /*
962 * Check for sane CTR_EL0.CWG value.
963 */
964 cwg = cache_type_cwg();
965 cls = cache_line_size();
966 if (!cwg)
967 pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
968 cls);
969 if (L1_CACHE_BYTES < cls)
970 pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
971 L1_CACHE_BYTES, cls);
972 }
973
974 static bool __maybe_unused
cpufeature_pan_not_uao(const struct arm64_cpu_capabilities * entry)975 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry)
976 {
977 return (cpus_have_cap(ARM64_HAS_PAN) && !cpus_have_cap(ARM64_HAS_UAO));
978 }
979