1 // SPDX-License-Identifier: GPL-2.0-only
3 * Contains CPU feature definitions
5 * Copyright (C) 2015 ARM Ltd.
8 #define pr_fmt(fmt) "CPU features: " fmt
10 #include <linux/bsearch.h>
11 #include <linux/cpumask.h>
12 #include <linux/crash_dump.h>
13 #include <linux/sort.h>
14 #include <linux/stop_machine.h>
15 #include <linux/types.h>
17 #include <linux/cpu.h>
19 #include <asm/cpufeature.h>
20 #include <asm/cpu_ops.h>
21 #include <asm/fpsimd.h>
22 #include <asm/mmu_context.h>
23 #include <asm/processor.h>
24 #include <asm/sysreg.h>
25 #include <asm/traps.h>
28 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
29 static unsigned long elf_hwcap __read_mostly;
32 #define COMPAT_ELF_HWCAP_DEFAULT \
33 (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
34 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
35 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
36 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
37 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
39 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
40 unsigned int compat_elf_hwcap2 __read_mostly;
43 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
44 EXPORT_SYMBOL(cpu_hwcaps);
45 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
47 /* Need also bit for ARM64_CB_PATCH */
48 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
51 * Flag to indicate if we have computed the system wide
52 * capabilities based on the boot time active CPUs. This
53 * will be used to determine if a new booting CPU should
54 * go through the verification process to make sure that it
55 * supports the system capabilities, without using a hotplug
58 static bool sys_caps_initialised;
60 static inline void set_sys_caps_initialised(void)
62 sys_caps_initialised = true;
65 static int dump_cpu_hwcaps(struct notifier_block *self, unsigned long v, void *p)
67 /* file-wide pr_fmt adds "CPU features: " prefix */
68 pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
72 static struct notifier_block cpu_hwcaps_notifier = {
73 .notifier_call = dump_cpu_hwcaps
76 static int __init register_cpu_hwcaps_dumper(void)
78 atomic_notifier_chain_register(&panic_notifier_list,
79 &cpu_hwcaps_notifier);
82 __initcall(register_cpu_hwcaps_dumper);
84 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
85 EXPORT_SYMBOL(cpu_hwcap_keys);
87 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
95 .safe_val = SAFE_VAL, \
98 /* Define a feature with unsigned values */
99 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
100 __ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
102 /* Define a feature with a signed value */
103 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
104 __ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
106 #define ARM64_FTR_END \
111 /* meta feature for alternatives */
112 static bool __maybe_unused
113 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
115 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
118 * NOTE: Any changes to the visibility of features should be kept in
119 * sync with the documentation of the CPU feature register ABI.
121 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
122 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
123 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
124 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
125 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
126 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
127 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
128 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
129 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
130 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
131 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
132 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
133 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
137 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
138 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
139 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
140 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
141 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
142 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
143 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
144 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
145 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
146 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
147 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
148 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_API_SHIFT, 4, 0),
149 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
150 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_APA_SHIFT, 4, 0),
151 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
155 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
156 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
157 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
158 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
159 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
160 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
161 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
162 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
163 S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
164 S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
165 /* Linux doesn't care about the EL3 */
166 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
167 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
168 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
169 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
173 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
174 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
178 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
179 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
180 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
181 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
182 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
183 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
184 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
185 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
186 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
187 ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
188 FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
192 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
194 * We already refuse to boot CPUs that don't support our configured
195 * page size, so we can only detect mismatches for a page size other
196 * than the one we're currently using. Unfortunately, SoCs like this
197 * exist in the wild so, even though we don't like it, we'll have to go
198 * along with it and treat them as non-strict.
200 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
201 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
202 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
204 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
205 /* Linux shouldn't care about secure memory */
206 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
207 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
208 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
210 * Differing PARange is fine as long as all peripherals and memory are mapped
211 * within the minimum PARange of all CPUs
213 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
217 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
218 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
219 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
220 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
221 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
222 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
223 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
227 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
228 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
229 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
230 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
231 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
232 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
233 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
234 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
238 static const struct arm64_ftr_bits ftr_ctr[] = {
239 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
240 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
241 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
242 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
243 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
244 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
246 * Linux can handle differing I-cache policies. Userspace JITs will
247 * make use of *minLine.
248 * If we have differing I-cache policies, report it as the weakest - VIPT.
250 ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_VIPT), /* L1Ip */
251 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
255 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
256 .name = "SYS_CTR_EL0",
260 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
261 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0xf), /* InnerShr */
262 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0), /* FCSE */
263 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0), /* AuxReg */
264 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0), /* TCM */
265 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* ShareLvl */
266 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0xf), /* OuterShr */
267 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* PMSA */
268 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* VMSA */
272 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
273 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 36, 28, 0),
274 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
275 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
276 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
277 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
279 * We can instantiate multiple PMU instances with different levels
282 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
283 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
284 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
288 static const struct arm64_ftr_bits ftr_mvfr2[] = {
289 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* FPMisc */
290 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* SIMDMisc */
294 static const struct arm64_ftr_bits ftr_dczid[] = {
295 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 4, 1, 1), /* DZP */
296 ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* BS */
301 static const struct arm64_ftr_bits ftr_id_isar5[] = {
302 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
303 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
304 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
305 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
306 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
307 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
311 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
312 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* ac2 */
316 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
317 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* State3 */
318 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), /* State2 */
319 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* State1 */
320 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* State0 */
324 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
325 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
326 S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf), /* PerfMon */
327 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
328 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
329 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
330 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
331 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
332 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
336 static const struct arm64_ftr_bits ftr_zcr[] = {
337 ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
338 ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0), /* LEN */
343 * Common ftr bits for a 32bit register with all hidden, strict
344 * attributes, with 4bit feature fields and a default safe value of
345 * 0. Covers the following 32bit registers:
346 * id_isar[0-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
348 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
349 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
350 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
351 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
352 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
353 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
354 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
355 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
356 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
360 /* Table for a single 32bit feature value */
361 static const struct arm64_ftr_bits ftr_single32[] = {
362 ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
366 static const struct arm64_ftr_bits ftr_raz[] = {
370 #define ARM64_FTR_REG(id, table) { \
372 .reg = &(struct arm64_ftr_reg){ \
374 .ftr_bits = &((table)[0]), \
377 static const struct __ftr_reg_entry {
379 struct arm64_ftr_reg *reg;
380 } arm64_ftr_regs[] = {
382 /* Op1 = 0, CRn = 0, CRm = 1 */
383 ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
384 ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_generic_32bits),
385 ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
386 ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
387 ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
388 ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
389 ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
391 /* Op1 = 0, CRn = 0, CRm = 2 */
392 ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_generic_32bits),
393 ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
394 ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
395 ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
396 ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_generic_32bits),
397 ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
398 ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
400 /* Op1 = 0, CRn = 0, CRm = 3 */
401 ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
402 ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
403 ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
405 /* Op1 = 0, CRn = 0, CRm = 4 */
406 ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
407 ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
408 ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
410 /* Op1 = 0, CRn = 0, CRm = 5 */
411 ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
412 ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
414 /* Op1 = 0, CRn = 0, CRm = 6 */
415 ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
416 ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
418 /* Op1 = 0, CRn = 0, CRm = 7 */
419 ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
420 ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
421 ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
423 /* Op1 = 0, CRn = 1, CRm = 2 */
424 ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
426 /* Op1 = 3, CRn = 0, CRm = 0 */
427 { SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
428 ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
430 /* Op1 = 3, CRn = 14, CRm = 0 */
431 ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
434 static int search_cmp_ftr_reg(const void *id, const void *regp)
436 return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
440 * get_arm64_ftr_reg - Lookup a feature register entry using its
441 * sys_reg() encoding. With the array arm64_ftr_regs sorted in the
442 * ascending order of sys_id , we use binary search to find a matching
445 * returns - Upon success, matching ftr_reg entry for id.
446 * - NULL on failure. It is upto the caller to decide
447 * the impact of a failure.
449 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
451 const struct __ftr_reg_entry *ret;
453 ret = bsearch((const void *)(unsigned long)sys_id,
455 ARRAY_SIZE(arm64_ftr_regs),
456 sizeof(arm64_ftr_regs[0]),
463 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
466 u64 mask = arm64_ftr_mask(ftrp);
469 reg |= (ftr_val << ftrp->shift) & mask;
473 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
478 switch (ftrp->type) {
480 ret = ftrp->safe_val;
483 ret = new < cur ? new : cur;
485 case FTR_HIGHER_OR_ZERO_SAFE:
489 case FTR_HIGHER_SAFE:
490 ret = new > cur ? new : cur;
499 static void __init sort_ftr_regs(void)
503 /* Check that the array is sorted so that we can do the binary search */
504 for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++)
505 BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
509 * Initialise the CPU feature register from Boot CPU values.
510 * Also initiliases the strict_mask for the register.
511 * Any bits that are not covered by an arm64_ftr_bits entry are considered
512 * RES0 for the system-wide value, and must strictly match.
514 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
517 u64 strict_mask = ~0x0ULL;
521 const struct arm64_ftr_bits *ftrp;
522 struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
526 for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
527 u64 ftr_mask = arm64_ftr_mask(ftrp);
528 s64 ftr_new = arm64_ftr_value(ftrp, new);
530 val = arm64_ftr_set_value(ftrp, val, ftr_new);
532 valid_mask |= ftr_mask;
534 strict_mask &= ~ftr_mask;
536 user_mask |= ftr_mask;
538 reg->user_val = arm64_ftr_set_value(ftrp,
546 reg->strict_mask = strict_mask;
547 reg->user_mask = user_mask;
550 extern const struct arm64_cpu_capabilities arm64_errata[];
551 static const struct arm64_cpu_capabilities arm64_features[];
554 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
556 for (; caps->matches; caps++) {
557 if (WARN(caps->capability >= ARM64_NCAPS,
558 "Invalid capability %d\n", caps->capability))
560 if (WARN(cpu_hwcaps_ptrs[caps->capability],
561 "Duplicate entry for capability %d\n",
564 cpu_hwcaps_ptrs[caps->capability] = caps;
568 static void __init init_cpu_hwcaps_indirect_list(void)
570 init_cpu_hwcaps_indirect_list_from_array(arm64_features);
571 init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
574 static void __init setup_boot_cpu_capabilities(void);
576 void __init init_cpu_features(struct cpuinfo_arm64 *info)
578 /* Before we start using the tables, make sure it is sorted */
581 init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
582 init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
583 init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
584 init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
585 init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
586 init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
587 init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
588 init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
589 init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
590 init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
591 init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
592 init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
593 init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
595 if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
596 init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
597 init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
598 init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
599 init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
600 init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
601 init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
602 init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
603 init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
604 init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
605 init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
606 init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
607 init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
608 init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
609 init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
610 init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
611 init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
614 if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
615 init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
620 * Initialize the indirect array of CPU hwcaps capabilities pointers
621 * before we handle the boot CPU below.
623 init_cpu_hwcaps_indirect_list();
626 * Detect and enable early CPU capabilities based on the boot CPU,
627 * after we have initialised the CPU feature infrastructure.
629 setup_boot_cpu_capabilities();
632 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
634 const struct arm64_ftr_bits *ftrp;
636 for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
637 s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
638 s64 ftr_new = arm64_ftr_value(ftrp, new);
640 if (ftr_cur == ftr_new)
642 /* Find a safe value */
643 ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
644 reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
649 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
651 struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
654 update_cpu_ftr_reg(regp, val);
655 if ((boot & regp->strict_mask) == (val & regp->strict_mask))
657 pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
658 regp->name, boot, cpu, val);
663 * Update system wide CPU feature registers with the values from a
664 * non-boot CPU. Also performs SANITY checks to make sure that there
665 * aren't any insane variations from that of the boot CPU.
667 void update_cpu_features(int cpu,
668 struct cpuinfo_arm64 *info,
669 struct cpuinfo_arm64 *boot)
674 * The kernel can handle differing I-cache policies, but otherwise
675 * caches should look identical. Userspace JITs will make use of
678 taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
679 info->reg_ctr, boot->reg_ctr);
682 * Userspace may perform DC ZVA instructions. Mismatched block sizes
683 * could result in too much or too little memory being zeroed if a
684 * process is preempted and migrated between CPUs.
686 taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
687 info->reg_dczid, boot->reg_dczid);
689 /* If different, timekeeping will be broken (especially with KVM) */
690 taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
691 info->reg_cntfrq, boot->reg_cntfrq);
694 * The kernel uses self-hosted debug features and expects CPUs to
695 * support identical debug features. We presently need CTX_CMPs, WRPs,
696 * and BRPs to be identical.
697 * ID_AA64DFR1 is currently RES0.
699 taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
700 info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
701 taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
702 info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
704 * Even in big.LITTLE, processors should be identical instruction-set
707 taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
708 info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
709 taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
710 info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
713 * Differing PARange support is fine as long as all peripherals and
714 * memory are mapped within the minimum PARange of all CPUs.
715 * Linux should not care about secure memory.
717 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
718 info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
719 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
720 info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
721 taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
722 info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
725 * EL3 is not our concern.
727 taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
728 info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
729 taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
730 info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
732 taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
733 info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
736 * If we have AArch32, we care about 32-bit features for compat.
737 * If the system doesn't support AArch32, don't update them.
739 if (id_aa64pfr0_32bit_el0(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
740 id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
742 taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
743 info->reg_id_dfr0, boot->reg_id_dfr0);
744 taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
745 info->reg_id_isar0, boot->reg_id_isar0);
746 taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
747 info->reg_id_isar1, boot->reg_id_isar1);
748 taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
749 info->reg_id_isar2, boot->reg_id_isar2);
750 taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
751 info->reg_id_isar3, boot->reg_id_isar3);
752 taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
753 info->reg_id_isar4, boot->reg_id_isar4);
754 taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
755 info->reg_id_isar5, boot->reg_id_isar5);
758 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
759 * ACTLR formats could differ across CPUs and therefore would have to
760 * be trapped for virtualization anyway.
762 taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
763 info->reg_id_mmfr0, boot->reg_id_mmfr0);
764 taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
765 info->reg_id_mmfr1, boot->reg_id_mmfr1);
766 taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
767 info->reg_id_mmfr2, boot->reg_id_mmfr2);
768 taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
769 info->reg_id_mmfr3, boot->reg_id_mmfr3);
770 taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
771 info->reg_id_pfr0, boot->reg_id_pfr0);
772 taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
773 info->reg_id_pfr1, boot->reg_id_pfr1);
774 taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
775 info->reg_mvfr0, boot->reg_mvfr0);
776 taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
777 info->reg_mvfr1, boot->reg_mvfr1);
778 taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
779 info->reg_mvfr2, boot->reg_mvfr2);
782 if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
783 taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
784 info->reg_zcr, boot->reg_zcr);
786 /* Probe vector lengths, unless we already gave up on SVE */
787 if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
788 !sys_caps_initialised)
793 * Mismatched CPU features are a recipe for disaster. Don't even
794 * pretend to support them.
797 pr_warn_once("Unsupported CPU feature variation detected.\n");
798 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
802 u64 read_sanitised_ftr_reg(u32 id)
804 struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
806 /* We shouldn't get a request for an unsupported register */
808 return regp->sys_val;
811 #define read_sysreg_case(r) \
812 case r: return read_sysreg_s(r)
815 * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
816 * Read the system register on the current CPU
818 static u64 __read_sysreg_by_encoding(u32 sys_id)
821 read_sysreg_case(SYS_ID_PFR0_EL1);
822 read_sysreg_case(SYS_ID_PFR1_EL1);
823 read_sysreg_case(SYS_ID_DFR0_EL1);
824 read_sysreg_case(SYS_ID_MMFR0_EL1);
825 read_sysreg_case(SYS_ID_MMFR1_EL1);
826 read_sysreg_case(SYS_ID_MMFR2_EL1);
827 read_sysreg_case(SYS_ID_MMFR3_EL1);
828 read_sysreg_case(SYS_ID_ISAR0_EL1);
829 read_sysreg_case(SYS_ID_ISAR1_EL1);
830 read_sysreg_case(SYS_ID_ISAR2_EL1);
831 read_sysreg_case(SYS_ID_ISAR3_EL1);
832 read_sysreg_case(SYS_ID_ISAR4_EL1);
833 read_sysreg_case(SYS_ID_ISAR5_EL1);
834 read_sysreg_case(SYS_MVFR0_EL1);
835 read_sysreg_case(SYS_MVFR1_EL1);
836 read_sysreg_case(SYS_MVFR2_EL1);
838 read_sysreg_case(SYS_ID_AA64PFR0_EL1);
839 read_sysreg_case(SYS_ID_AA64PFR1_EL1);
840 read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
841 read_sysreg_case(SYS_ID_AA64DFR0_EL1);
842 read_sysreg_case(SYS_ID_AA64DFR1_EL1);
843 read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
844 read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
845 read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
846 read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
847 read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
849 read_sysreg_case(SYS_CNTFRQ_EL0);
850 read_sysreg_case(SYS_CTR_EL0);
851 read_sysreg_case(SYS_DCZID_EL0);
859 #include <linux/irqchip/arm-gic-v3.h>
862 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
864 int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
866 return val >= entry->min_field_value;
870 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
874 WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
875 if (scope == SCOPE_SYSTEM)
876 val = read_sanitised_ftr_reg(entry->sys_reg);
878 val = __read_sysreg_by_encoding(entry->sys_reg);
880 return feature_matches(val, entry);
883 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
887 if (!has_cpuid_feature(entry, scope))
890 has_sre = gic_enable_sre();
892 pr_warn_once("%s present but disabled by higher exception level\n",
898 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
900 u32 midr = read_cpuid_id();
902 /* Cavium ThunderX pass 1.x and 2.x */
903 return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
904 MIDR_CPU_VAR_REV(0, 0),
905 MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
908 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
910 u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
912 return cpuid_feature_extract_signed_field(pfr0,
913 ID_AA64PFR0_FP_SHIFT) < 0;
916 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
921 if (scope == SCOPE_SYSTEM)
922 ctr = arm64_ftr_reg_ctrel0.sys_val;
924 ctr = read_cpuid_effective_cachetype();
926 return ctr & BIT(CTR_IDC_SHIFT);
929 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
932 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
933 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
934 * to the CTR_EL0 on this CPU and emulate it with the real/safe
937 if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
938 sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
941 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
946 if (scope == SCOPE_SYSTEM)
947 ctr = arm64_ftr_reg_ctrel0.sys_val;
949 ctr = read_cpuid_cachetype();
951 return ctr & BIT(CTR_DIC_SHIFT);
954 static bool __maybe_unused
955 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
958 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
959 * may share TLB entries with a CPU stuck in the crashed
962 if (is_kdump_kernel())
965 return has_cpuid_feature(entry, scope);
968 static bool __meltdown_safe = true;
969 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
971 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
974 /* List of CPUs that are not vulnerable and don't need KPTI */
975 static const struct midr_range kpti_safe_list[] = {
976 MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
977 MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
978 MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
979 MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
980 MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
981 MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
982 MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
983 MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
984 MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
985 MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
988 char const *str = "kpti command line option";
991 meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
993 /* Defer to CPU feature registers */
994 if (has_cpuid_feature(entry, scope))
995 meltdown_safe = true;
998 __meltdown_safe = false;
1001 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1002 * ThunderX leads to apparent I-cache corruption of kernel text, which
1003 * ends as well as you might imagine. Don't even try.
1005 if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1006 str = "ARM64_WORKAROUND_CAVIUM_27456";
1010 /* Useful for KASLR robustness */
1011 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0) {
1012 if (!__kpti_forced) {
1018 if (cpu_mitigations_off() && !__kpti_forced) {
1019 str = "mitigations=off";
1023 if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1024 pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1029 if (__kpti_forced) {
1030 pr_info_once("kernel page table isolation forced %s by %s\n",
1031 __kpti_forced > 0 ? "ON" : "OFF", str);
1032 return __kpti_forced > 0;
1035 return !meltdown_safe;
1038 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1040 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1042 typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1043 extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1044 kpti_remap_fn *remap_fn;
1046 static bool kpti_applied = false;
1047 int cpu = smp_processor_id();
1050 * We don't need to rewrite the page-tables if either we've done
1051 * it already or we have KASLR enabled and therefore have not
1052 * created any global mappings at all.
1054 if (kpti_applied || kaslr_offset() > 0)
1057 remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1059 cpu_install_idmap();
1060 remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1061 cpu_uninstall_idmap();
1064 kpti_applied = true;
1070 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1073 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
1075 static int __init parse_kpti(char *str)
1078 int ret = strtobool(str, &enabled);
1083 __kpti_forced = enabled ? 1 : -1;
1086 early_param("kpti", parse_kpti);
1088 #ifdef CONFIG_ARM64_HW_AFDBM
1089 static inline void __cpu_enable_hw_dbm(void)
1091 u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1093 write_sysreg(tcr, tcr_el1);
1097 static bool cpu_has_broken_dbm(void)
1099 /* List of CPUs which have broken DBM support. */
1100 static const struct midr_range cpus[] = {
1101 #ifdef CONFIG_ARM64_ERRATUM_1024718
1102 MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0), // A55 r0p0 -r1p0
1107 return is_midr_in_range_list(read_cpuid_id(), cpus);
1110 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1112 return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1113 !cpu_has_broken_dbm();
1116 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1118 if (cpu_can_use_dbm(cap))
1119 __cpu_enable_hw_dbm();
1122 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1125 static bool detected = false;
1127 * DBM is a non-conflicting feature. i.e, the kernel can safely
1128 * run a mix of CPUs with and without the feature. So, we
1129 * unconditionally enable the capability to allow any late CPU
1130 * to use the feature. We only enable the control bits on the
1131 * CPU, if it actually supports.
1133 * We have to make sure we print the "feature" detection only
1134 * when at least one CPU actually uses it. So check if this CPU
1135 * can actually use it and print the message exactly once.
1137 * This is safe as all CPUs (including secondary CPUs - due to the
1138 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1139 * goes through the "matches" check exactly once. Also if a CPU
1140 * matches the criteria, it is guaranteed that the CPU will turn
1141 * the DBM on, as the capability is unconditionally enabled.
1143 if (!detected && cpu_can_use_dbm(cap)) {
1145 pr_info("detected: Hardware dirty bit management\n");
1153 #ifdef CONFIG_ARM64_VHE
1154 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1156 return is_kernel_in_hyp_mode();
1159 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1162 * Copy register values that aren't redirected by hardware.
1164 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1165 * this value to tpidr_el2 before we patch the code. Once we've done
1166 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1169 if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1170 write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1174 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1176 u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1178 /* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1179 WARN_ON(val & (7 << 27 | 7 << 21));
1182 #ifdef CONFIG_ARM64_SSBD
1183 static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr)
1185 if (user_mode(regs))
1188 if (instr & BIT(PSTATE_Imm_shift))
1189 regs->pstate |= PSR_SSBS_BIT;
1191 regs->pstate &= ~PSR_SSBS_BIT;
1193 arm64_skip_faulting_instruction(regs, 4);
1197 static struct undef_hook ssbs_emulation_hook = {
1198 .instr_mask = ~(1U << PSTATE_Imm_shift),
1199 .instr_val = 0xd500401f | PSTATE_SSBS,
1200 .fn = ssbs_emulation_handler,
1203 static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused)
1205 static bool undef_hook_registered = false;
1206 static DEFINE_RAW_SPINLOCK(hook_lock);
1208 raw_spin_lock(&hook_lock);
1209 if (!undef_hook_registered) {
1210 register_undef_hook(&ssbs_emulation_hook);
1211 undef_hook_registered = true;
1213 raw_spin_unlock(&hook_lock);
1215 if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) {
1216 sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS);
1217 arm64_set_ssbd_mitigation(false);
1219 arm64_set_ssbd_mitigation(true);
1222 #endif /* CONFIG_ARM64_SSBD */
1224 #ifdef CONFIG_ARM64_PAN
1225 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1228 * We modify PSTATE. This won't work from irq context as the PSTATE
1229 * is discarded once we return from the exception.
1231 WARN_ON_ONCE(in_interrupt());
1233 sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1234 asm(SET_PSTATE_PAN(1));
1236 #endif /* CONFIG_ARM64_PAN */
1238 #ifdef CONFIG_ARM64_RAS_EXTN
1239 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1241 /* Firmware may have left a deferred SError in this register. */
1242 write_sysreg_s(0, SYS_DISR_EL1);
1244 #endif /* CONFIG_ARM64_RAS_EXTN */
1246 #ifdef CONFIG_ARM64_PTR_AUTH
1247 static void cpu_enable_address_auth(struct arm64_cpu_capabilities const *cap)
1249 sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ENIA | SCTLR_ELx_ENIB |
1250 SCTLR_ELx_ENDA | SCTLR_ELx_ENDB);
1252 #endif /* CONFIG_ARM64_PTR_AUTH */
1254 #ifdef CONFIG_ARM64_PSEUDO_NMI
1255 static bool enable_pseudo_nmi;
1257 static int __init early_enable_pseudo_nmi(char *p)
1259 return strtobool(p, &enable_pseudo_nmi);
1261 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1263 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1266 return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1270 static const struct arm64_cpu_capabilities arm64_features[] = {
1272 .desc = "GIC system register CPU interface",
1273 .capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1274 .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1275 .matches = has_useable_gicv3_cpuif,
1276 .sys_reg = SYS_ID_AA64PFR0_EL1,
1277 .field_pos = ID_AA64PFR0_GIC_SHIFT,
1278 .sign = FTR_UNSIGNED,
1279 .min_field_value = 1,
1281 #ifdef CONFIG_ARM64_PAN
1283 .desc = "Privileged Access Never",
1284 .capability = ARM64_HAS_PAN,
1285 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1286 .matches = has_cpuid_feature,
1287 .sys_reg = SYS_ID_AA64MMFR1_EL1,
1288 .field_pos = ID_AA64MMFR1_PAN_SHIFT,
1289 .sign = FTR_UNSIGNED,
1290 .min_field_value = 1,
1291 .cpu_enable = cpu_enable_pan,
1293 #endif /* CONFIG_ARM64_PAN */
1294 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
1296 .desc = "LSE atomic instructions",
1297 .capability = ARM64_HAS_LSE_ATOMICS,
1298 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1299 .matches = has_cpuid_feature,
1300 .sys_reg = SYS_ID_AA64ISAR0_EL1,
1301 .field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1302 .sign = FTR_UNSIGNED,
1303 .min_field_value = 2,
1305 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
1307 .desc = "Software prefetching using PRFM",
1308 .capability = ARM64_HAS_NO_HW_PREFETCH,
1309 .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1310 .matches = has_no_hw_prefetch,
1312 #ifdef CONFIG_ARM64_UAO
1314 .desc = "User Access Override",
1315 .capability = ARM64_HAS_UAO,
1316 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1317 .matches = has_cpuid_feature,
1318 .sys_reg = SYS_ID_AA64MMFR2_EL1,
1319 .field_pos = ID_AA64MMFR2_UAO_SHIFT,
1320 .min_field_value = 1,
1322 * We rely on stop_machine() calling uao_thread_switch() to set
1323 * UAO immediately after patching.
1326 #endif /* CONFIG_ARM64_UAO */
1327 #ifdef CONFIG_ARM64_PAN
1329 .capability = ARM64_ALT_PAN_NOT_UAO,
1330 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1331 .matches = cpufeature_pan_not_uao,
1333 #endif /* CONFIG_ARM64_PAN */
1334 #ifdef CONFIG_ARM64_VHE
1336 .desc = "Virtualization Host Extensions",
1337 .capability = ARM64_HAS_VIRT_HOST_EXTN,
1338 .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1339 .matches = runs_at_el2,
1340 .cpu_enable = cpu_copy_el2regs,
1342 #endif /* CONFIG_ARM64_VHE */
1344 .desc = "32-bit EL0 Support",
1345 .capability = ARM64_HAS_32BIT_EL0,
1346 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1347 .matches = has_cpuid_feature,
1348 .sys_reg = SYS_ID_AA64PFR0_EL1,
1349 .sign = FTR_UNSIGNED,
1350 .field_pos = ID_AA64PFR0_EL0_SHIFT,
1351 .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1354 .desc = "Kernel page table isolation (KPTI)",
1355 .capability = ARM64_UNMAP_KERNEL_AT_EL0,
1356 .type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1358 * The ID feature fields below are used to indicate that
1359 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1362 .sys_reg = SYS_ID_AA64PFR0_EL1,
1363 .field_pos = ID_AA64PFR0_CSV3_SHIFT,
1364 .min_field_value = 1,
1365 .matches = unmap_kernel_at_el0,
1366 .cpu_enable = kpti_install_ng_mappings,
1369 /* FP/SIMD is not implemented */
1370 .capability = ARM64_HAS_NO_FPSIMD,
1371 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1372 .min_field_value = 0,
1373 .matches = has_no_fpsimd,
1375 #ifdef CONFIG_ARM64_PMEM
1377 .desc = "Data cache clean to Point of Persistence",
1378 .capability = ARM64_HAS_DCPOP,
1379 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1380 .matches = has_cpuid_feature,
1381 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1382 .field_pos = ID_AA64ISAR1_DPB_SHIFT,
1383 .min_field_value = 1,
1386 .desc = "Data cache clean to Point of Deep Persistence",
1387 .capability = ARM64_HAS_DCPODP,
1388 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1389 .matches = has_cpuid_feature,
1390 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1391 .sign = FTR_UNSIGNED,
1392 .field_pos = ID_AA64ISAR1_DPB_SHIFT,
1393 .min_field_value = 2,
1396 #ifdef CONFIG_ARM64_SVE
1398 .desc = "Scalable Vector Extension",
1399 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1400 .capability = ARM64_SVE,
1401 .sys_reg = SYS_ID_AA64PFR0_EL1,
1402 .sign = FTR_UNSIGNED,
1403 .field_pos = ID_AA64PFR0_SVE_SHIFT,
1404 .min_field_value = ID_AA64PFR0_SVE,
1405 .matches = has_cpuid_feature,
1406 .cpu_enable = sve_kernel_enable,
1408 #endif /* CONFIG_ARM64_SVE */
1409 #ifdef CONFIG_ARM64_RAS_EXTN
1411 .desc = "RAS Extension Support",
1412 .capability = ARM64_HAS_RAS_EXTN,
1413 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1414 .matches = has_cpuid_feature,
1415 .sys_reg = SYS_ID_AA64PFR0_EL1,
1416 .sign = FTR_UNSIGNED,
1417 .field_pos = ID_AA64PFR0_RAS_SHIFT,
1418 .min_field_value = ID_AA64PFR0_RAS_V1,
1419 .cpu_enable = cpu_clear_disr,
1421 #endif /* CONFIG_ARM64_RAS_EXTN */
1423 .desc = "Data cache clean to the PoU not required for I/D coherence",
1424 .capability = ARM64_HAS_CACHE_IDC,
1425 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1426 .matches = has_cache_idc,
1427 .cpu_enable = cpu_emulate_effective_ctr,
1430 .desc = "Instruction cache invalidation not required for I/D coherence",
1431 .capability = ARM64_HAS_CACHE_DIC,
1432 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1433 .matches = has_cache_dic,
1436 .desc = "Stage-2 Force Write-Back",
1437 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1438 .capability = ARM64_HAS_STAGE2_FWB,
1439 .sys_reg = SYS_ID_AA64MMFR2_EL1,
1440 .sign = FTR_UNSIGNED,
1441 .field_pos = ID_AA64MMFR2_FWB_SHIFT,
1442 .min_field_value = 1,
1443 .matches = has_cpuid_feature,
1444 .cpu_enable = cpu_has_fwb,
1446 #ifdef CONFIG_ARM64_HW_AFDBM
1449 * Since we turn this on always, we don't want the user to
1450 * think that the feature is available when it may not be.
1451 * So hide the description.
1453 * .desc = "Hardware pagetable Dirty Bit Management",
1456 .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1457 .capability = ARM64_HW_DBM,
1458 .sys_reg = SYS_ID_AA64MMFR1_EL1,
1459 .sign = FTR_UNSIGNED,
1460 .field_pos = ID_AA64MMFR1_HADBS_SHIFT,
1461 .min_field_value = 2,
1462 .matches = has_hw_dbm,
1463 .cpu_enable = cpu_enable_hw_dbm,
1467 .desc = "CRC32 instructions",
1468 .capability = ARM64_HAS_CRC32,
1469 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1470 .matches = has_cpuid_feature,
1471 .sys_reg = SYS_ID_AA64ISAR0_EL1,
1472 .field_pos = ID_AA64ISAR0_CRC32_SHIFT,
1473 .min_field_value = 1,
1475 #ifdef CONFIG_ARM64_SSBD
1477 .desc = "Speculative Store Bypassing Safe (SSBS)",
1478 .capability = ARM64_SSBS,
1479 .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1480 .matches = has_cpuid_feature,
1481 .sys_reg = SYS_ID_AA64PFR1_EL1,
1482 .field_pos = ID_AA64PFR1_SSBS_SHIFT,
1483 .sign = FTR_UNSIGNED,
1484 .min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
1485 .cpu_enable = cpu_enable_ssbs,
1488 #ifdef CONFIG_ARM64_CNP
1490 .desc = "Common not Private translations",
1491 .capability = ARM64_HAS_CNP,
1492 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1493 .matches = has_useable_cnp,
1494 .sys_reg = SYS_ID_AA64MMFR2_EL1,
1495 .sign = FTR_UNSIGNED,
1496 .field_pos = ID_AA64MMFR2_CNP_SHIFT,
1497 .min_field_value = 1,
1498 .cpu_enable = cpu_enable_cnp,
1502 .desc = "Speculation barrier (SB)",
1503 .capability = ARM64_HAS_SB,
1504 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1505 .matches = has_cpuid_feature,
1506 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1507 .field_pos = ID_AA64ISAR1_SB_SHIFT,
1508 .sign = FTR_UNSIGNED,
1509 .min_field_value = 1,
1511 #ifdef CONFIG_ARM64_PTR_AUTH
1513 .desc = "Address authentication (architected algorithm)",
1514 .capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
1515 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1516 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1517 .sign = FTR_UNSIGNED,
1518 .field_pos = ID_AA64ISAR1_APA_SHIFT,
1519 .min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
1520 .matches = has_cpuid_feature,
1521 .cpu_enable = cpu_enable_address_auth,
1524 .desc = "Address authentication (IMP DEF algorithm)",
1525 .capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
1526 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1527 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1528 .sign = FTR_UNSIGNED,
1529 .field_pos = ID_AA64ISAR1_API_SHIFT,
1530 .min_field_value = ID_AA64ISAR1_API_IMP_DEF,
1531 .matches = has_cpuid_feature,
1532 .cpu_enable = cpu_enable_address_auth,
1535 .desc = "Generic authentication (architected algorithm)",
1536 .capability = ARM64_HAS_GENERIC_AUTH_ARCH,
1537 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1538 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1539 .sign = FTR_UNSIGNED,
1540 .field_pos = ID_AA64ISAR1_GPA_SHIFT,
1541 .min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
1542 .matches = has_cpuid_feature,
1545 .desc = "Generic authentication (IMP DEF algorithm)",
1546 .capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
1547 .type = ARM64_CPUCAP_SYSTEM_FEATURE,
1548 .sys_reg = SYS_ID_AA64ISAR1_EL1,
1549 .sign = FTR_UNSIGNED,
1550 .field_pos = ID_AA64ISAR1_GPI_SHIFT,
1551 .min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
1552 .matches = has_cpuid_feature,
1554 #endif /* CONFIG_ARM64_PTR_AUTH */
1555 #ifdef CONFIG_ARM64_PSEUDO_NMI
1558 * Depends on having GICv3
1560 .desc = "IRQ priority masking",
1561 .capability = ARM64_HAS_IRQ_PRIO_MASKING,
1562 .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1563 .matches = can_use_gic_priorities,
1564 .sys_reg = SYS_ID_AA64PFR0_EL1,
1565 .field_pos = ID_AA64PFR0_GIC_SHIFT,
1566 .sign = FTR_UNSIGNED,
1567 .min_field_value = 1,
1573 #define HWCAP_CPUID_MATCH(reg, field, s, min_value) \
1574 .matches = has_cpuid_feature, \
1576 .field_pos = field, \
1578 .min_field_value = min_value,
1580 #define __HWCAP_CAP(name, cap_type, cap) \
1582 .type = ARM64_CPUCAP_SYSTEM_FEATURE, \
1583 .hwcap_type = cap_type, \
1586 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap) \
1588 __HWCAP_CAP(#cap, cap_type, cap) \
1589 HWCAP_CPUID_MATCH(reg, field, s, min_value) \
1592 #define HWCAP_MULTI_CAP(list, cap_type, cap) \
1594 __HWCAP_CAP(#cap, cap_type, cap) \
1595 .matches = cpucap_multi_entry_cap_matches, \
1596 .match_list = list, \
1599 #ifdef CONFIG_ARM64_PTR_AUTH
1600 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
1602 HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
1603 FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
1606 HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
1607 FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
1612 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
1614 HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
1615 FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
1618 HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
1619 FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
1625 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
1626 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
1627 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
1628 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
1629 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
1630 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
1631 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
1632 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
1633 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
1634 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
1635 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
1636 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
1637 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
1638 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
1639 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
1640 HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
1641 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
1642 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
1643 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
1644 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
1645 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
1646 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
1647 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
1648 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
1649 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
1650 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
1651 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
1652 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
1653 HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
1654 HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
1655 #ifdef CONFIG_ARM64_SVE
1656 HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
1657 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
1658 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
1659 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
1660 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
1661 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
1662 HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
1664 HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
1665 #ifdef CONFIG_ARM64_PTR_AUTH
1666 HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
1667 HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
1672 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
1673 #ifdef CONFIG_COMPAT
1674 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
1675 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
1676 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
1677 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
1678 HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
1683 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1685 switch (cap->hwcap_type) {
1687 cpu_set_feature(cap->hwcap);
1689 #ifdef CONFIG_COMPAT
1690 case CAP_COMPAT_HWCAP:
1691 compat_elf_hwcap |= (u32)cap->hwcap;
1693 case CAP_COMPAT_HWCAP2:
1694 compat_elf_hwcap2 |= (u32)cap->hwcap;
1703 /* Check if we have a particular HWCAP enabled */
1704 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
1708 switch (cap->hwcap_type) {
1710 rc = cpu_have_feature(cap->hwcap);
1712 #ifdef CONFIG_COMPAT
1713 case CAP_COMPAT_HWCAP:
1714 rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
1716 case CAP_COMPAT_HWCAP2:
1717 rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
1728 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
1730 /* We support emulation of accesses to CPU ID feature registers */
1731 cpu_set_named_feature(CPUID);
1732 for (; hwcaps->matches; hwcaps++)
1733 if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
1734 cap_set_elf_hwcap(hwcaps);
1737 static void update_cpu_capabilities(u16 scope_mask)
1740 const struct arm64_cpu_capabilities *caps;
1742 scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1743 for (i = 0; i < ARM64_NCAPS; i++) {
1744 caps = cpu_hwcaps_ptrs[i];
1745 if (!caps || !(caps->type & scope_mask) ||
1746 cpus_have_cap(caps->capability) ||
1747 !caps->matches(caps, cpucap_default_scope(caps)))
1751 pr_info("detected: %s\n", caps->desc);
1752 cpus_set_cap(caps->capability);
1754 if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
1755 set_bit(caps->capability, boot_capabilities);
1760 * Enable all the available capabilities on this CPU. The capabilities
1761 * with BOOT_CPU scope are handled separately and hence skipped here.
1763 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
1766 u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
1768 for_each_available_cap(i) {
1769 const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
1774 if (!(cap->type & non_boot_scope))
1777 if (cap->cpu_enable)
1778 cap->cpu_enable(cap);
1784 * Run through the enabled capabilities and enable() it on all active
1787 static void __init enable_cpu_capabilities(u16 scope_mask)
1790 const struct arm64_cpu_capabilities *caps;
1793 scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1794 boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
1796 for (i = 0; i < ARM64_NCAPS; i++) {
1799 caps = cpu_hwcaps_ptrs[i];
1800 if (!caps || !(caps->type & scope_mask))
1802 num = caps->capability;
1803 if (!cpus_have_cap(num))
1806 /* Ensure cpus_have_const_cap(num) works */
1807 static_branch_enable(&cpu_hwcap_keys[num]);
1809 if (boot_scope && caps->cpu_enable)
1811 * Capabilities with SCOPE_BOOT_CPU scope are finalised
1812 * before any secondary CPU boots. Thus, each secondary
1813 * will enable the capability as appropriate via
1814 * check_local_cpu_capabilities(). The only exception is
1815 * the boot CPU, for which the capability must be
1816 * enabled here. This approach avoids costly
1817 * stop_machine() calls for this case.
1819 caps->cpu_enable(caps);
1823 * For all non-boot scope capabilities, use stop_machine()
1824 * as it schedules the work allowing us to modify PSTATE,
1825 * instead of on_each_cpu() which uses an IPI, giving us a
1826 * PSTATE that disappears when we return.
1829 stop_machine(cpu_enable_non_boot_scope_capabilities,
1830 NULL, cpu_online_mask);
1834 * Run through the list of capabilities to check for conflicts.
1835 * If the system has already detected a capability, take necessary
1836 * action on this CPU.
1838 * Returns "false" on conflicts.
1840 static bool verify_local_cpu_caps(u16 scope_mask)
1843 bool cpu_has_cap, system_has_cap;
1844 const struct arm64_cpu_capabilities *caps;
1846 scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
1848 for (i = 0; i < ARM64_NCAPS; i++) {
1849 caps = cpu_hwcaps_ptrs[i];
1850 if (!caps || !(caps->type & scope_mask))
1853 cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
1854 system_has_cap = cpus_have_cap(caps->capability);
1856 if (system_has_cap) {
1858 * Check if the new CPU misses an advertised feature,
1859 * which is not safe to miss.
1861 if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
1864 * We have to issue cpu_enable() irrespective of
1865 * whether the CPU has it or not, as it is enabeld
1866 * system wide. It is upto the call back to take
1867 * appropriate action on this CPU.
1869 if (caps->cpu_enable)
1870 caps->cpu_enable(caps);
1873 * Check if the CPU has this capability if it isn't
1874 * safe to have when the system doesn't.
1876 if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
1881 if (i < ARM64_NCAPS) {
1882 pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
1883 smp_processor_id(), caps->capability,
1884 caps->desc, system_has_cap, cpu_has_cap);
1892 * Check for CPU features that are used in early boot
1893 * based on the Boot CPU value.
1895 static void check_early_cpu_features(void)
1897 verify_cpu_asid_bits();
1899 * Early features are used by the kernel already. If there
1900 * is a conflict, we cannot proceed further.
1902 if (!verify_local_cpu_caps(SCOPE_BOOT_CPU))
1907 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
1910 for (; caps->matches; caps++)
1911 if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
1912 pr_crit("CPU%d: missing HWCAP: %s\n",
1913 smp_processor_id(), caps->desc);
1918 static void verify_sve_features(void)
1920 u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
1921 u64 zcr = read_zcr_features();
1923 unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
1924 unsigned int len = zcr & ZCR_ELx_LEN_MASK;
1926 if (len < safe_len || sve_verify_vq_map()) {
1927 pr_crit("CPU%d: SVE: vector length support mismatch\n",
1928 smp_processor_id());
1932 /* Add checks on other ZCR bits here if necessary */
1937 * Run through the enabled system capabilities and enable() it on this CPU.
1938 * The capabilities were decided based on the available CPUs at the boot time.
1939 * Any new CPU should match the system wide status of the capability. If the
1940 * new CPU doesn't have a capability which the system now has enabled, we
1941 * cannot do anything to fix it up and could cause unexpected failures. So
1944 static void verify_local_cpu_capabilities(void)
1947 * The capabilities with SCOPE_BOOT_CPU are checked from
1948 * check_early_cpu_features(), as they need to be verified
1949 * on all secondary CPUs.
1951 if (!verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU))
1954 verify_local_elf_hwcaps(arm64_elf_hwcaps);
1956 if (system_supports_32bit_el0())
1957 verify_local_elf_hwcaps(compat_elf_hwcaps);
1959 if (system_supports_sve())
1960 verify_sve_features();
1963 void check_local_cpu_capabilities(void)
1966 * All secondary CPUs should conform to the early CPU features
1967 * in use by the kernel based on boot CPU.
1969 check_early_cpu_features();
1972 * If we haven't finalised the system capabilities, this CPU gets
1973 * a chance to update the errata work arounds and local features.
1974 * Otherwise, this CPU should verify that it has all the system
1975 * advertised capabilities.
1977 if (!sys_caps_initialised)
1978 update_cpu_capabilities(SCOPE_LOCAL_CPU);
1980 verify_local_cpu_capabilities();
1983 static void __init setup_boot_cpu_capabilities(void)
1985 /* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
1986 update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
1987 /* Enable the SCOPE_BOOT_CPU capabilities alone right away */
1988 enable_cpu_capabilities(SCOPE_BOOT_CPU);
1991 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
1992 EXPORT_SYMBOL(arm64_const_caps_ready);
1994 static void __init mark_const_caps_ready(void)
1996 static_branch_enable(&arm64_const_caps_ready);
1999 bool this_cpu_has_cap(unsigned int n)
2001 if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2002 const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2005 return cap->matches(cap, SCOPE_LOCAL_CPU);
2011 void cpu_set_feature(unsigned int num)
2013 WARN_ON(num >= MAX_CPU_FEATURES);
2014 elf_hwcap |= BIT(num);
2016 EXPORT_SYMBOL_GPL(cpu_set_feature);
2018 bool cpu_have_feature(unsigned int num)
2020 WARN_ON(num >= MAX_CPU_FEATURES);
2021 return elf_hwcap & BIT(num);
2023 EXPORT_SYMBOL_GPL(cpu_have_feature);
2025 unsigned long cpu_get_elf_hwcap(void)
2028 * We currently only populate the first 32 bits of AT_HWCAP. Please
2029 * note that for userspace compatibility we guarantee that bits 62
2030 * and 63 will always be returned as 0.
2032 return lower_32_bits(elf_hwcap);
2035 unsigned long cpu_get_elf_hwcap2(void)
2037 return upper_32_bits(elf_hwcap);
2040 static void __init setup_system_capabilities(void)
2043 * We have finalised the system-wide safe feature
2044 * registers, finalise the capabilities that depend
2045 * on it. Also enable all the available capabilities,
2046 * that are not enabled already.
2048 update_cpu_capabilities(SCOPE_SYSTEM);
2049 enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2052 void __init setup_cpu_features(void)
2056 setup_system_capabilities();
2057 mark_const_caps_ready();
2058 setup_elf_hwcaps(arm64_elf_hwcaps);
2060 if (system_supports_32bit_el0())
2061 setup_elf_hwcaps(compat_elf_hwcaps);
2063 if (system_uses_ttbr0_pan())
2064 pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2067 minsigstksz_setup();
2069 /* Advertise that we have computed the system capabilities */
2070 set_sys_caps_initialised();
2073 * Check for sane CTR_EL0.CWG value.
2075 cwg = cache_type_cwg();
2077 pr_warn("No Cache Writeback Granule information, assuming %d\n",
2081 static bool __maybe_unused
2082 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
2084 return (cpus_have_const_cap(ARM64_HAS_PAN) && !cpus_have_const_cap(ARM64_HAS_UAO));
2087 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2089 cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2093 * We emulate only the following system register space.
2094 * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2095 * See Table C5-6 System instruction encodings for System register accesses,
2096 * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2098 static inline bool __attribute_const__ is_emulated(u32 id)
2100 return (sys_reg_Op0(id) == 0x3 &&
2101 sys_reg_CRn(id) == 0x0 &&
2102 sys_reg_Op1(id) == 0x0 &&
2103 (sys_reg_CRm(id) == 0 ||
2104 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2108 * With CRm == 0, reg should be one of :
2109 * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2111 static inline int emulate_id_reg(u32 id, u64 *valp)
2115 *valp = read_cpuid_id();
2118 *valp = SYS_MPIDR_SAFE_VAL;
2120 case SYS_REVIDR_EL1:
2121 /* IMPLEMENTATION DEFINED values are emulated with 0 */
2131 static int emulate_sys_reg(u32 id, u64 *valp)
2133 struct arm64_ftr_reg *regp;
2135 if (!is_emulated(id))
2138 if (sys_reg_CRm(id) == 0)
2139 return emulate_id_reg(id, valp);
2141 regp = get_arm64_ftr_reg(id);
2143 *valp = arm64_ftr_reg_user_value(regp);
2146 * The untracked registers are either IMPLEMENTATION DEFINED
2147 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2153 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2158 rc = emulate_sys_reg(sys_reg, &val);
2160 pt_regs_write_reg(regs, rt, val);
2161 arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2166 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2171 * sys_reg values are defined as used in mrs/msr instruction.
2172 * shift the imm value to get the encoding.
2174 sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2175 rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2176 return do_emulate_mrs(regs, sys_reg, rt);
2179 static struct undef_hook mrs_hook = {
2180 .instr_mask = 0xfff00000,
2181 .instr_val = 0xd5300000,
2182 .pstate_mask = PSR_AA32_MODE_MASK,
2183 .pstate_val = PSR_MODE_EL0t,
2187 static int __init enable_mrs_emulation(void)
2189 register_undef_hook(&mrs_hook);
2193 core_initcall(enable_mrs_emulation);
2195 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
2198 if (__meltdown_safe)
2199 return sprintf(buf, "Not affected\n");
2201 if (arm64_kernel_unmapped_at_el0())
2202 return sprintf(buf, "Mitigation: PTI\n");
2204 return sprintf(buf, "Vulnerable\n");