xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision da1d9caf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Contains CPU feature definitions
4  *
5  * Copyright (C) 2015 ARM Ltd.
6  *
7  * A note for the weary kernel hacker: the code here is confusing and hard to
8  * follow! That's partly because it's solving a nasty problem, but also because
9  * there's a little bit of over-abstraction that tends to obscure what's going
10  * on behind a maze of helper functions and macros.
11  *
12  * The basic problem is that hardware folks have started gluing together CPUs
13  * with distinct architectural features; in some cases even creating SoCs where
14  * user-visible instructions are available only on a subset of the available
15  * cores. We try to address this by snapshotting the feature registers of the
16  * boot CPU and comparing these with the feature registers of each secondary
17  * CPU when bringing them up. If there is a mismatch, then we update the
18  * snapshot state to indicate the lowest-common denominator of the feature,
19  * known as the "safe" value. This snapshot state can be queried to view the
20  * "sanitised" value of a feature register.
21  *
22  * The sanitised register values are used to decide which capabilities we
23  * have in the system. These may be in the form of traditional "hwcaps"
24  * advertised to userspace or internal "cpucaps" which are used to configure
25  * things like alternative patching and static keys. While a feature mismatch
26  * may result in a TAINT_CPU_OUT_OF_SPEC kernel taint, a capability mismatch
27  * may prevent a CPU from being onlined at all.
28  *
29  * Some implementation details worth remembering:
30  *
31  * - Mismatched features are *always* sanitised to a "safe" value, which
32  *   usually indicates that the feature is not supported.
33  *
34  * - A mismatched feature marked with FTR_STRICT will cause a "SANITY CHECK"
35  *   warning when onlining an offending CPU and the kernel will be tainted
36  *   with TAINT_CPU_OUT_OF_SPEC.
37  *
38  * - Features marked as FTR_VISIBLE have their sanitised value visible to
39  *   userspace. FTR_VISIBLE features in registers that are only visible
40  *   to EL0 by trapping *must* have a corresponding HWCAP so that late
41  *   onlining of CPUs cannot lead to features disappearing at runtime.
42  *
43  * - A "feature" is typically a 4-bit register field. A "capability" is the
44  *   high-level description derived from the sanitised field value.
45  *
46  * - Read the Arm ARM (DDI 0487F.a) section D13.1.3 ("Principles of the ID
47  *   scheme for fields in ID registers") to understand when feature fields
48  *   may be signed or unsigned (FTR_SIGNED and FTR_UNSIGNED accordingly).
49  *
50  * - KVM exposes its own view of the feature registers to guest operating
51  *   systems regardless of FTR_VISIBLE. This is typically driven from the
52  *   sanitised register values to allow virtual CPUs to be migrated between
53  *   arbitrary physical CPUs, but some features not present on the host are
54  *   also advertised and emulated. Look at sys_reg_descs[] for the gory
55  *   details.
56  *
57  * - If the arm64_ftr_bits[] for a register has a missing field, then this
58  *   field is treated as STRICT RES0, including for read_sanitised_ftr_reg().
59  *   This is stronger than FTR_HIDDEN and can be used to hide features from
60  *   KVM guests.
61  */
62 
63 #define pr_fmt(fmt) "CPU features: " fmt
64 
65 #include <linux/bsearch.h>
66 #include <linux/cpumask.h>
67 #include <linux/crash_dump.h>
68 #include <linux/sort.h>
69 #include <linux/stop_machine.h>
70 #include <linux/sysfs.h>
71 #include <linux/types.h>
72 #include <linux/minmax.h>
73 #include <linux/mm.h>
74 #include <linux/cpu.h>
75 #include <linux/kasan.h>
76 #include <linux/percpu.h>
77 
78 #include <asm/cpu.h>
79 #include <asm/cpufeature.h>
80 #include <asm/cpu_ops.h>
81 #include <asm/fpsimd.h>
82 #include <asm/insn.h>
83 #include <asm/kvm_host.h>
84 #include <asm/mmu_context.h>
85 #include <asm/mte.h>
86 #include <asm/processor.h>
87 #include <asm/smp.h>
88 #include <asm/sysreg.h>
89 #include <asm/traps.h>
90 #include <asm/vectors.h>
91 #include <asm/virt.h>
92 
93 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
94 static unsigned long elf_hwcap __read_mostly;
95 
96 #ifdef CONFIG_COMPAT
97 #define COMPAT_ELF_HWCAP_DEFAULT	\
98 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
99 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
100 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
101 				 COMPAT_HWCAP_LPAE)
102 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
103 unsigned int compat_elf_hwcap2 __read_mostly;
104 #endif
105 
106 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
107 EXPORT_SYMBOL(cpu_hwcaps);
108 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
109 
110 /* Need also bit for ARM64_CB_PATCH */
111 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
112 
113 bool arm64_use_ng_mappings = false;
114 EXPORT_SYMBOL(arm64_use_ng_mappings);
115 
116 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
117 
118 /*
119  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
120  * support it?
121  */
122 static bool __read_mostly allow_mismatched_32bit_el0;
123 
124 /*
125  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
126  * seen at least one CPU capable of 32-bit EL0.
127  */
128 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
129 
130 /*
131  * Mask of CPUs supporting 32-bit EL0.
132  * Only valid if arm64_mismatched_32bit_el0 is enabled.
133  */
134 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
135 
136 /*
137  * Flag to indicate if we have computed the system wide
138  * capabilities based on the boot time active CPUs. This
139  * will be used to determine if a new booting CPU should
140  * go through the verification process to make sure that it
141  * supports the system capabilities, without using a hotplug
142  * notifier. This is also used to decide if we could use
143  * the fast path for checking constant CPU caps.
144  */
145 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
146 EXPORT_SYMBOL(arm64_const_caps_ready);
147 static inline void finalize_system_capabilities(void)
148 {
149 	static_branch_enable(&arm64_const_caps_ready);
150 }
151 
152 void dump_cpu_features(void)
153 {
154 	/* file-wide pr_fmt adds "CPU features: " prefix */
155 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
156 }
157 
158 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
159 EXPORT_SYMBOL(cpu_hwcap_keys);
160 
161 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
162 	{						\
163 		.sign = SIGNED,				\
164 		.visible = VISIBLE,			\
165 		.strict = STRICT,			\
166 		.type = TYPE,				\
167 		.shift = SHIFT,				\
168 		.width = WIDTH,				\
169 		.safe_val = SAFE_VAL,			\
170 	}
171 
172 /* Define a feature with unsigned values */
173 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
174 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
175 
176 /* Define a feature with a signed value */
177 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
178 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
179 
180 #define ARM64_FTR_END					\
181 	{						\
182 		.width = 0,				\
183 	}
184 
185 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
186 
187 static bool __system_matches_cap(unsigned int n);
188 
189 /*
190  * NOTE: Any changes to the visibility of features should be kept in
191  * sync with the documentation of the CPU feature register ABI.
192  */
193 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_RNDR_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_TLB_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_TS_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_FHM_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_DP_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SM4_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SM3_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA3_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_RDM_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_ATOMIC_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_CRC32_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA2_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA1_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_AES_SHIFT, 4, 0),
208 	ARM64_FTR_END,
209 };
210 
211 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
212 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
219 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
221 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
223 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
226 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
228 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
229 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
230 	ARM64_FTR_END,
231 };
232 
233 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
235 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
236 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR2_APA3_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
238 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_GPA3_SHIFT, 4, 0),
239 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_WFXT_SHIFT, 4, 0),
241 	ARM64_FTR_END,
242 };
243 
244 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
245 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
246 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
247 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
251 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
252 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
253 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
254 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
255 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
256 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
257 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
258 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
259 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
260 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
261 	ARM64_FTR_END,
262 };
263 
264 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
265 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
266 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SME_SHIFT, 4, 0),
267 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
268 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
269 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
270 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
271 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
272 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
273 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
274 	ARM64_FTR_END,
275 };
276 
277 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
278 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
279 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
280 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
281 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
282 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
283 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
284 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
285 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
286 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
287 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
288 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
289 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
290 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
291 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
292 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
293 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
294 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
295 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
296 	ARM64_FTR_END,
297 };
298 
299 static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
300 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
301 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_FA64_SHIFT, 1, 0),
302 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
303 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_I16I64_SHIFT, 4, 0),
304 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
305 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_F64F64_SHIFT, 1, 0),
306 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
307 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_I8I32_SHIFT, 4, 0),
308 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
309 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_F16F32_SHIFT, 1, 0),
310 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
311 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_B16F32_SHIFT, 1, 0),
312 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
313 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_F32F32_SHIFT, 1, 0),
314 	ARM64_FTR_END,
315 };
316 
317 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
318 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
319 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
320 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
321 	/*
322 	 * Page size not being supported at Stage-2 is not fatal. You
323 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
324 	 * your favourite nesting hypervisor.
325 	 *
326 	 * There is a small corner case where the hypervisor explicitly
327 	 * advertises a given granule size at Stage-2 (value 2) on some
328 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
329 	 * vCPUs. Although this is not forbidden by the architecture, it
330 	 * indicates that the hypervisor is being silly (or buggy).
331 	 *
332 	 * We make no effort to cope with this and pretend that if these
333 	 * fields are inconsistent across vCPUs, then it isn't worth
334 	 * trying to bring KVM up.
335 	 */
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
339 	/*
340 	 * We already refuse to boot CPUs that don't support our configured
341 	 * page size, so we can only detect mismatches for a page size other
342 	 * than the one we're currently using. Unfortunately, SoCs like this
343 	 * exist in the wild so, even though we don't like it, we'll have to go
344 	 * along with it and treat them as non-strict.
345 	 */
346 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
347 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
349 
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
351 	/* Linux shouldn't care about secure memory */
352 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
354 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
355 	/*
356 	 * Differing PARange is fine as long as all peripherals and memory are mapped
357 	 * within the minimum PARange of all CPUs
358 	 */
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
360 	ARM64_FTR_END,
361 };
362 
363 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
364 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
365 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
367 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
368 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
369 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
370 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
371 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
372 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
373 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
374 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
375 	ARM64_FTR_END,
376 };
377 
378 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
379 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
380 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
381 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
382 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
383 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
384 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
385 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
390 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
391 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
393 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
394 	ARM64_FTR_END,
395 };
396 
397 static const struct arm64_ftr_bits ftr_ctr[] = {
398 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
399 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
400 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
401 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
402 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
403 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
404 	/*
405 	 * Linux can handle differing I-cache policies. Userspace JITs will
406 	 * make use of *minLine.
407 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
408 	 */
409 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
410 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
411 	ARM64_FTR_END,
412 };
413 
414 static struct arm64_ftr_override __ro_after_init no_override = { };
415 
416 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
417 	.name		= "SYS_CTR_EL0",
418 	.ftr_bits	= ftr_ctr,
419 	.override	= &no_override,
420 };
421 
422 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
423 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
424 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
425 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
427 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
428 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
429 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
430 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
431 	ARM64_FTR_END,
432 };
433 
434 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
435 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
436 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
440 	/*
441 	 * We can instantiate multiple PMU instances with different levels
442 	 * of support.
443 	 */
444 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
446 	ARM64_FTR_END,
447 };
448 
449 static const struct arm64_ftr_bits ftr_mvfr2[] = {
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
452 	ARM64_FTR_END,
453 };
454 
455 static const struct arm64_ftr_bits ftr_dczid[] = {
456 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
457 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
458 	ARM64_FTR_END,
459 };
460 
461 static const struct arm64_ftr_bits ftr_gmid[] = {
462 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, SYS_GMID_EL1_BS_SHIFT, 4, 0),
463 	ARM64_FTR_END,
464 };
465 
466 static const struct arm64_ftr_bits ftr_id_isar0[] = {
467 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
468 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
473 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
474 	ARM64_FTR_END,
475 };
476 
477 static const struct arm64_ftr_bits ftr_id_isar5[] = {
478 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
479 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
480 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
484 	ARM64_FTR_END,
485 };
486 
487 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
489 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
490 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
491 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
492 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
495 
496 	/*
497 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
498 	 * external abort on speculative read. It is safe to assume that an
499 	 * SError might be generated than it will not be. Hence it has been
500 	 * classified as FTR_HIGHER_SAFE.
501 	 */
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
503 	ARM64_FTR_END,
504 };
505 
506 static const struct arm64_ftr_bits ftr_id_isar4[] = {
507 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
515 	ARM64_FTR_END,
516 };
517 
518 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
519 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
520 	ARM64_FTR_END,
521 };
522 
523 static const struct arm64_ftr_bits ftr_id_isar6[] = {
524 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
525 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
526 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
531 	ARM64_FTR_END,
532 };
533 
534 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
535 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
536 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
538 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
541 	ARM64_FTR_END,
542 };
543 
544 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
545 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
546 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
547 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
548 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
549 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
550 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
551 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
552 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
553 	ARM64_FTR_END,
554 };
555 
556 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
557 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
558 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
559 	ARM64_FTR_END,
560 };
561 
562 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
563 	/* [31:28] TraceFilt */
564 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
565 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
566 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
568 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
569 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
570 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
571 	ARM64_FTR_END,
572 };
573 
574 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
575 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
576 	ARM64_FTR_END,
577 };
578 
579 static const struct arm64_ftr_bits ftr_zcr[] = {
580 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
581 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_WIDTH, 0),	/* LEN */
582 	ARM64_FTR_END,
583 };
584 
585 static const struct arm64_ftr_bits ftr_smcr[] = {
586 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
587 		SMCR_ELx_LEN_SHIFT, SMCR_ELx_LEN_WIDTH, 0),	/* LEN */
588 	ARM64_FTR_END,
589 };
590 
591 /*
592  * Common ftr bits for a 32bit register with all hidden, strict
593  * attributes, with 4bit feature fields and a default safe value of
594  * 0. Covers the following 32bit registers:
595  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
596  */
597 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
598 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
599 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
600 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
601 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
602 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
603 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
604 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
605 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
606 	ARM64_FTR_END,
607 };
608 
609 /* Table for a single 32bit feature value */
610 static const struct arm64_ftr_bits ftr_single32[] = {
611 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
612 	ARM64_FTR_END,
613 };
614 
615 static const struct arm64_ftr_bits ftr_raz[] = {
616 	ARM64_FTR_END,
617 };
618 
619 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
620 		.sys_id = id,					\
621 		.reg = 	&(struct arm64_ftr_reg){		\
622 			.name = id_str,				\
623 			.override = (ovr),			\
624 			.ftr_bits = &((table)[0]),		\
625 	}}
626 
627 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
628 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
629 
630 #define ARM64_FTR_REG(id, table)		\
631 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
632 
633 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
634 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
635 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
636 struct arm64_ftr_override __ro_after_init id_aa64isar2_override;
637 
638 static const struct __ftr_reg_entry {
639 	u32			sys_id;
640 	struct arm64_ftr_reg 	*reg;
641 } arm64_ftr_regs[] = {
642 
643 	/* Op1 = 0, CRn = 0, CRm = 1 */
644 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
645 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
646 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
647 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
648 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
649 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
650 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
651 
652 	/* Op1 = 0, CRn = 0, CRm = 2 */
653 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
654 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
655 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
656 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
657 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
658 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
659 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
660 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
661 
662 	/* Op1 = 0, CRn = 0, CRm = 3 */
663 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
664 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
665 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
666 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
667 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
668 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
669 
670 	/* Op1 = 0, CRn = 0, CRm = 4 */
671 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
672 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
673 			       &id_aa64pfr1_override),
674 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
675 	ARM64_FTR_REG(SYS_ID_AA64SMFR0_EL1, ftr_id_aa64smfr0),
676 
677 	/* Op1 = 0, CRn = 0, CRm = 5 */
678 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
679 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
680 
681 	/* Op1 = 0, CRn = 0, CRm = 6 */
682 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
683 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
684 			       &id_aa64isar1_override),
685 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2,
686 			       &id_aa64isar2_override),
687 
688 	/* Op1 = 0, CRn = 0, CRm = 7 */
689 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
690 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
691 			       &id_aa64mmfr1_override),
692 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
693 
694 	/* Op1 = 0, CRn = 1, CRm = 2 */
695 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
696 	ARM64_FTR_REG(SYS_SMCR_EL1, ftr_smcr),
697 
698 	/* Op1 = 1, CRn = 0, CRm = 0 */
699 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
700 
701 	/* Op1 = 3, CRn = 0, CRm = 0 */
702 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
703 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
704 
705 	/* Op1 = 3, CRn = 14, CRm = 0 */
706 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
707 };
708 
709 static int search_cmp_ftr_reg(const void *id, const void *regp)
710 {
711 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
712 }
713 
714 /*
715  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
716  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
717  * ascending order of sys_id, we use binary search to find a matching
718  * entry.
719  *
720  * returns - Upon success,  matching ftr_reg entry for id.
721  *         - NULL on failure. It is upto the caller to decide
722  *	     the impact of a failure.
723  */
724 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
725 {
726 	const struct __ftr_reg_entry *ret;
727 
728 	ret = bsearch((const void *)(unsigned long)sys_id,
729 			arm64_ftr_regs,
730 			ARRAY_SIZE(arm64_ftr_regs),
731 			sizeof(arm64_ftr_regs[0]),
732 			search_cmp_ftr_reg);
733 	if (ret)
734 		return ret->reg;
735 	return NULL;
736 }
737 
738 /*
739  * get_arm64_ftr_reg - Looks up a feature register entry using
740  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
741  *
742  * returns - Upon success,  matching ftr_reg entry for id.
743  *         - NULL on failure but with an WARN_ON().
744  */
745 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
746 {
747 	struct arm64_ftr_reg *reg;
748 
749 	reg = get_arm64_ftr_reg_nowarn(sys_id);
750 
751 	/*
752 	 * Requesting a non-existent register search is an error. Warn
753 	 * and let the caller handle it.
754 	 */
755 	WARN_ON(!reg);
756 	return reg;
757 }
758 
759 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
760 			       s64 ftr_val)
761 {
762 	u64 mask = arm64_ftr_mask(ftrp);
763 
764 	reg &= ~mask;
765 	reg |= (ftr_val << ftrp->shift) & mask;
766 	return reg;
767 }
768 
769 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
770 				s64 cur)
771 {
772 	s64 ret = 0;
773 
774 	switch (ftrp->type) {
775 	case FTR_EXACT:
776 		ret = ftrp->safe_val;
777 		break;
778 	case FTR_LOWER_SAFE:
779 		ret = min(new, cur);
780 		break;
781 	case FTR_HIGHER_OR_ZERO_SAFE:
782 		if (!cur || !new)
783 			break;
784 		fallthrough;
785 	case FTR_HIGHER_SAFE:
786 		ret = max(new, cur);
787 		break;
788 	default:
789 		BUG();
790 	}
791 
792 	return ret;
793 }
794 
795 static void __init sort_ftr_regs(void)
796 {
797 	unsigned int i;
798 
799 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
800 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
801 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
802 		unsigned int j = 0;
803 
804 		/*
805 		 * Features here must be sorted in descending order with respect
806 		 * to their shift values and should not overlap with each other.
807 		 */
808 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
809 			unsigned int width = ftr_reg->ftr_bits[j].width;
810 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
811 			unsigned int prev_shift;
812 
813 			WARN((shift  + width) > 64,
814 				"%s has invalid feature at shift %d\n",
815 				ftr_reg->name, shift);
816 
817 			/*
818 			 * Skip the first feature. There is nothing to
819 			 * compare against for now.
820 			 */
821 			if (j == 0)
822 				continue;
823 
824 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
825 			WARN((shift + width) > prev_shift,
826 				"%s has feature overlap at shift %d\n",
827 				ftr_reg->name, shift);
828 		}
829 
830 		/*
831 		 * Skip the first register. There is nothing to
832 		 * compare against for now.
833 		 */
834 		if (i == 0)
835 			continue;
836 		/*
837 		 * Registers here must be sorted in ascending order with respect
838 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
839 		 * to work correctly.
840 		 */
841 		BUG_ON(arm64_ftr_regs[i].sys_id <= arm64_ftr_regs[i - 1].sys_id);
842 	}
843 }
844 
845 /*
846  * Initialise the CPU feature register from Boot CPU values.
847  * Also initiliases the strict_mask for the register.
848  * Any bits that are not covered by an arm64_ftr_bits entry are considered
849  * RES0 for the system-wide value, and must strictly match.
850  */
851 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
852 {
853 	u64 val = 0;
854 	u64 strict_mask = ~0x0ULL;
855 	u64 user_mask = 0;
856 	u64 valid_mask = 0;
857 
858 	const struct arm64_ftr_bits *ftrp;
859 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
860 
861 	if (!reg)
862 		return;
863 
864 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
865 		u64 ftr_mask = arm64_ftr_mask(ftrp);
866 		s64 ftr_new = arm64_ftr_value(ftrp, new);
867 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
868 
869 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
870 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
871 			char *str = NULL;
872 
873 			if (ftr_ovr != tmp) {
874 				/* Unsafe, remove the override */
875 				reg->override->mask &= ~ftr_mask;
876 				reg->override->val &= ~ftr_mask;
877 				tmp = ftr_ovr;
878 				str = "ignoring override";
879 			} else if (ftr_new != tmp) {
880 				/* Override was valid */
881 				ftr_new = tmp;
882 				str = "forced";
883 			} else if (ftr_ovr == tmp) {
884 				/* Override was the safe value */
885 				str = "already set";
886 			}
887 
888 			if (str)
889 				pr_warn("%s[%d:%d]: %s to %llx\n",
890 					reg->name,
891 					ftrp->shift + ftrp->width - 1,
892 					ftrp->shift, str, tmp);
893 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
894 			reg->override->val &= ~ftr_mask;
895 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
896 				reg->name,
897 				ftrp->shift + ftrp->width - 1,
898 				ftrp->shift);
899 		}
900 
901 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
902 
903 		valid_mask |= ftr_mask;
904 		if (!ftrp->strict)
905 			strict_mask &= ~ftr_mask;
906 		if (ftrp->visible)
907 			user_mask |= ftr_mask;
908 		else
909 			reg->user_val = arm64_ftr_set_value(ftrp,
910 							    reg->user_val,
911 							    ftrp->safe_val);
912 	}
913 
914 	val &= valid_mask;
915 
916 	reg->sys_val = val;
917 	reg->strict_mask = strict_mask;
918 	reg->user_mask = user_mask;
919 }
920 
921 extern const struct arm64_cpu_capabilities arm64_errata[];
922 static const struct arm64_cpu_capabilities arm64_features[];
923 
924 static void __init
925 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
926 {
927 	for (; caps->matches; caps++) {
928 		if (WARN(caps->capability >= ARM64_NCAPS,
929 			"Invalid capability %d\n", caps->capability))
930 			continue;
931 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
932 			"Duplicate entry for capability %d\n",
933 			caps->capability))
934 			continue;
935 		cpu_hwcaps_ptrs[caps->capability] = caps;
936 	}
937 }
938 
939 static void __init init_cpu_hwcaps_indirect_list(void)
940 {
941 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
942 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
943 }
944 
945 static void __init setup_boot_cpu_capabilities(void);
946 
947 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
948 {
949 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
950 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
951 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
952 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
953 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
954 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
955 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
956 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
957 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
958 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
959 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
960 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
961 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
962 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
963 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
964 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
965 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
966 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
967 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
968 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
969 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
970 }
971 
972 void __init init_cpu_features(struct cpuinfo_arm64 *info)
973 {
974 	/* Before we start using the tables, make sure it is sorted */
975 	sort_ftr_regs();
976 
977 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
978 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
979 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
980 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
981 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
982 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
983 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
984 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
985 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
986 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
987 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
988 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
989 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
990 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
991 	init_cpu_ftr_reg(SYS_ID_AA64SMFR0_EL1, info->reg_id_aa64smfr0);
992 
993 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
994 		init_32bit_cpu_features(&info->aarch32);
995 
996 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
997 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
998 		vec_init_vq_map(ARM64_VEC_SVE);
999 	}
1000 
1001 	if (id_aa64pfr1_sme(info->reg_id_aa64pfr1)) {
1002 		init_cpu_ftr_reg(SYS_SMCR_EL1, info->reg_smcr);
1003 		if (IS_ENABLED(CONFIG_ARM64_SME))
1004 			vec_init_vq_map(ARM64_VEC_SME);
1005 	}
1006 
1007 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
1008 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
1009 
1010 	/*
1011 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
1012 	 * before we handle the boot CPU below.
1013 	 */
1014 	init_cpu_hwcaps_indirect_list();
1015 
1016 	/*
1017 	 * Detect and enable early CPU capabilities based on the boot CPU,
1018 	 * after we have initialised the CPU feature infrastructure.
1019 	 */
1020 	setup_boot_cpu_capabilities();
1021 }
1022 
1023 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
1024 {
1025 	const struct arm64_ftr_bits *ftrp;
1026 
1027 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
1028 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
1029 		s64 ftr_new = arm64_ftr_value(ftrp, new);
1030 
1031 		if (ftr_cur == ftr_new)
1032 			continue;
1033 		/* Find a safe value */
1034 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
1035 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
1036 	}
1037 
1038 }
1039 
1040 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
1041 {
1042 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1043 
1044 	if (!regp)
1045 		return 0;
1046 
1047 	update_cpu_ftr_reg(regp, val);
1048 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
1049 		return 0;
1050 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
1051 			regp->name, boot, cpu, val);
1052 	return 1;
1053 }
1054 
1055 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1056 {
1057 	const struct arm64_ftr_bits *ftrp;
1058 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1059 
1060 	if (!regp)
1061 		return;
1062 
1063 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1064 		if (ftrp->shift == field) {
1065 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1066 			break;
1067 		}
1068 	}
1069 
1070 	/* Bogus field? */
1071 	WARN_ON(!ftrp->width);
1072 }
1073 
1074 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1075 					 struct cpuinfo_arm64 *boot)
1076 {
1077 	static bool boot_cpu_32bit_regs_overridden = false;
1078 
1079 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1080 		return;
1081 
1082 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1083 		return;
1084 
1085 	boot->aarch32 = info->aarch32;
1086 	init_32bit_cpu_features(&boot->aarch32);
1087 	boot_cpu_32bit_regs_overridden = true;
1088 }
1089 
1090 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1091 				     struct cpuinfo_32bit *boot)
1092 {
1093 	int taint = 0;
1094 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1095 
1096 	/*
1097 	 * If we don't have AArch32 at EL1, then relax the strictness of
1098 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1099 	 */
1100 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1101 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1102 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1103 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1104 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1105 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1106 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1107 	}
1108 
1109 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1110 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1111 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1112 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1113 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1114 				      info->reg_id_isar0, boot->reg_id_isar0);
1115 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1116 				      info->reg_id_isar1, boot->reg_id_isar1);
1117 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1118 				      info->reg_id_isar2, boot->reg_id_isar2);
1119 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1120 				      info->reg_id_isar3, boot->reg_id_isar3);
1121 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1122 				      info->reg_id_isar4, boot->reg_id_isar4);
1123 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1124 				      info->reg_id_isar5, boot->reg_id_isar5);
1125 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1126 				      info->reg_id_isar6, boot->reg_id_isar6);
1127 
1128 	/*
1129 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1130 	 * ACTLR formats could differ across CPUs and therefore would have to
1131 	 * be trapped for virtualization anyway.
1132 	 */
1133 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1134 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1135 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1136 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1137 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1138 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1139 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1140 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1141 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1142 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1143 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1144 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1145 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1146 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1147 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1148 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1149 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1150 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1151 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1152 				      info->reg_mvfr0, boot->reg_mvfr0);
1153 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1154 				      info->reg_mvfr1, boot->reg_mvfr1);
1155 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1156 				      info->reg_mvfr2, boot->reg_mvfr2);
1157 
1158 	return taint;
1159 }
1160 
1161 /*
1162  * Update system wide CPU feature registers with the values from a
1163  * non-boot CPU. Also performs SANITY checks to make sure that there
1164  * aren't any insane variations from that of the boot CPU.
1165  */
1166 void update_cpu_features(int cpu,
1167 			 struct cpuinfo_arm64 *info,
1168 			 struct cpuinfo_arm64 *boot)
1169 {
1170 	int taint = 0;
1171 
1172 	/*
1173 	 * The kernel can handle differing I-cache policies, but otherwise
1174 	 * caches should look identical. Userspace JITs will make use of
1175 	 * *minLine.
1176 	 */
1177 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1178 				      info->reg_ctr, boot->reg_ctr);
1179 
1180 	/*
1181 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1182 	 * could result in too much or too little memory being zeroed if a
1183 	 * process is preempted and migrated between CPUs.
1184 	 */
1185 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1186 				      info->reg_dczid, boot->reg_dczid);
1187 
1188 	/* If different, timekeeping will be broken (especially with KVM) */
1189 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1190 				      info->reg_cntfrq, boot->reg_cntfrq);
1191 
1192 	/*
1193 	 * The kernel uses self-hosted debug features and expects CPUs to
1194 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1195 	 * and BRPs to be identical.
1196 	 * ID_AA64DFR1 is currently RES0.
1197 	 */
1198 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1199 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1200 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1201 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1202 	/*
1203 	 * Even in big.LITTLE, processors should be identical instruction-set
1204 	 * wise.
1205 	 */
1206 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1207 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1208 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1209 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1210 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1211 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1212 
1213 	/*
1214 	 * Differing PARange support is fine as long as all peripherals and
1215 	 * memory are mapped within the minimum PARange of all CPUs.
1216 	 * Linux should not care about secure memory.
1217 	 */
1218 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1219 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1220 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1221 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1222 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1223 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1224 
1225 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1226 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1227 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1228 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1229 
1230 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1231 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1232 
1233 	taint |= check_update_ftr_reg(SYS_ID_AA64SMFR0_EL1, cpu,
1234 				      info->reg_id_aa64smfr0, boot->reg_id_aa64smfr0);
1235 
1236 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1237 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1238 					info->reg_zcr, boot->reg_zcr);
1239 
1240 		/* Probe vector lengths, unless we already gave up on SVE */
1241 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1242 		    !system_capabilities_finalized())
1243 			vec_update_vq_map(ARM64_VEC_SVE);
1244 	}
1245 
1246 	if (id_aa64pfr1_sme(info->reg_id_aa64pfr1)) {
1247 		taint |= check_update_ftr_reg(SYS_SMCR_EL1, cpu,
1248 					info->reg_smcr, boot->reg_smcr);
1249 
1250 		/* Probe vector lengths, unless we already gave up on SME */
1251 		if (id_aa64pfr1_sme(read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1)) &&
1252 		    !system_capabilities_finalized())
1253 			vec_update_vq_map(ARM64_VEC_SME);
1254 	}
1255 
1256 	/*
1257 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1258 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1259 	 * value is the same on all CPUs.
1260 	 */
1261 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1262 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1263 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1264 					      info->reg_gmid, boot->reg_gmid);
1265 	}
1266 
1267 	/*
1268 	 * If we don't have AArch32 at all then skip the checks entirely
1269 	 * as the register values may be UNKNOWN and we're not going to be
1270 	 * using them for anything.
1271 	 *
1272 	 * This relies on a sanitised view of the AArch64 ID registers
1273 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1274 	 */
1275 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1276 		lazy_init_32bit_cpu_features(info, boot);
1277 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1278 						   &boot->aarch32);
1279 	}
1280 
1281 	/*
1282 	 * Mismatched CPU features are a recipe for disaster. Don't even
1283 	 * pretend to support them.
1284 	 */
1285 	if (taint) {
1286 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1287 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1288 	}
1289 }
1290 
1291 u64 read_sanitised_ftr_reg(u32 id)
1292 {
1293 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1294 
1295 	if (!regp)
1296 		return 0;
1297 	return regp->sys_val;
1298 }
1299 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1300 
1301 #define read_sysreg_case(r)	\
1302 	case r:		val = read_sysreg_s(r); break;
1303 
1304 /*
1305  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1306  * Read the system register on the current CPU
1307  */
1308 u64 __read_sysreg_by_encoding(u32 sys_id)
1309 {
1310 	struct arm64_ftr_reg *regp;
1311 	u64 val;
1312 
1313 	switch (sys_id) {
1314 	read_sysreg_case(SYS_ID_PFR0_EL1);
1315 	read_sysreg_case(SYS_ID_PFR1_EL1);
1316 	read_sysreg_case(SYS_ID_PFR2_EL1);
1317 	read_sysreg_case(SYS_ID_DFR0_EL1);
1318 	read_sysreg_case(SYS_ID_DFR1_EL1);
1319 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1320 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1321 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1322 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1323 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1324 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1325 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1326 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1327 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1328 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1329 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1330 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1331 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1332 	read_sysreg_case(SYS_MVFR0_EL1);
1333 	read_sysreg_case(SYS_MVFR1_EL1);
1334 	read_sysreg_case(SYS_MVFR2_EL1);
1335 
1336 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1337 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1338 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1339 	read_sysreg_case(SYS_ID_AA64SMFR0_EL1);
1340 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1341 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1342 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1343 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1344 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1345 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1346 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1347 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1348 
1349 	read_sysreg_case(SYS_CNTFRQ_EL0);
1350 	read_sysreg_case(SYS_CTR_EL0);
1351 	read_sysreg_case(SYS_DCZID_EL0);
1352 
1353 	default:
1354 		BUG();
1355 		return 0;
1356 	}
1357 
1358 	regp  = get_arm64_ftr_reg(sys_id);
1359 	if (regp) {
1360 		val &= ~regp->override->mask;
1361 		val |= (regp->override->val & regp->override->mask);
1362 	}
1363 
1364 	return val;
1365 }
1366 
1367 #include <linux/irqchip/arm-gic-v3.h>
1368 
1369 static bool
1370 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1371 {
1372 	int val = cpuid_feature_extract_field_width(reg, entry->field_pos,
1373 						    entry->field_width,
1374 						    entry->sign);
1375 
1376 	return val >= entry->min_field_value;
1377 }
1378 
1379 static bool
1380 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1381 {
1382 	u64 val;
1383 
1384 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1385 	if (scope == SCOPE_SYSTEM)
1386 		val = read_sanitised_ftr_reg(entry->sys_reg);
1387 	else
1388 		val = __read_sysreg_by_encoding(entry->sys_reg);
1389 
1390 	return feature_matches(val, entry);
1391 }
1392 
1393 const struct cpumask *system_32bit_el0_cpumask(void)
1394 {
1395 	if (!system_supports_32bit_el0())
1396 		return cpu_none_mask;
1397 
1398 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1399 		return cpu_32bit_el0_mask;
1400 
1401 	return cpu_possible_mask;
1402 }
1403 
1404 static int __init parse_32bit_el0_param(char *str)
1405 {
1406 	allow_mismatched_32bit_el0 = true;
1407 	return 0;
1408 }
1409 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1410 
1411 static ssize_t aarch32_el0_show(struct device *dev,
1412 				struct device_attribute *attr, char *buf)
1413 {
1414 	const struct cpumask *mask = system_32bit_el0_cpumask();
1415 
1416 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1417 }
1418 static const DEVICE_ATTR_RO(aarch32_el0);
1419 
1420 static int __init aarch32_el0_sysfs_init(void)
1421 {
1422 	if (!allow_mismatched_32bit_el0)
1423 		return 0;
1424 
1425 	return device_create_file(cpu_subsys.dev_root, &dev_attr_aarch32_el0);
1426 }
1427 device_initcall(aarch32_el0_sysfs_init);
1428 
1429 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1430 {
1431 	if (!has_cpuid_feature(entry, scope))
1432 		return allow_mismatched_32bit_el0;
1433 
1434 	if (scope == SCOPE_SYSTEM)
1435 		pr_info("detected: 32-bit EL0 Support\n");
1436 
1437 	return true;
1438 }
1439 
1440 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1441 {
1442 	bool has_sre;
1443 
1444 	if (!has_cpuid_feature(entry, scope))
1445 		return false;
1446 
1447 	has_sre = gic_enable_sre();
1448 	if (!has_sre)
1449 		pr_warn_once("%s present but disabled by higher exception level\n",
1450 			     entry->desc);
1451 
1452 	return has_sre;
1453 }
1454 
1455 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1456 {
1457 	u32 midr = read_cpuid_id();
1458 
1459 	/* Cavium ThunderX pass 1.x and 2.x */
1460 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1461 		MIDR_CPU_VAR_REV(0, 0),
1462 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1463 }
1464 
1465 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1466 {
1467 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1468 
1469 	return cpuid_feature_extract_signed_field(pfr0,
1470 					ID_AA64PFR0_FP_SHIFT) < 0;
1471 }
1472 
1473 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1474 			  int scope)
1475 {
1476 	u64 ctr;
1477 
1478 	if (scope == SCOPE_SYSTEM)
1479 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1480 	else
1481 		ctr = read_cpuid_effective_cachetype();
1482 
1483 	return ctr & BIT(CTR_IDC_SHIFT);
1484 }
1485 
1486 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1487 {
1488 	/*
1489 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1490 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1491 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1492 	 * value.
1493 	 */
1494 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1495 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1496 }
1497 
1498 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1499 			  int scope)
1500 {
1501 	u64 ctr;
1502 
1503 	if (scope == SCOPE_SYSTEM)
1504 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1505 	else
1506 		ctr = read_cpuid_cachetype();
1507 
1508 	return ctr & BIT(CTR_DIC_SHIFT);
1509 }
1510 
1511 static bool __maybe_unused
1512 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1513 {
1514 	/*
1515 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1516 	 * may share TLB entries with a CPU stuck in the crashed
1517 	 * kernel.
1518 	 */
1519 	if (is_kdump_kernel())
1520 		return false;
1521 
1522 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1523 		return false;
1524 
1525 	return has_cpuid_feature(entry, scope);
1526 }
1527 
1528 /*
1529  * This check is triggered during the early boot before the cpufeature
1530  * is initialised. Checking the status on the local CPU allows the boot
1531  * CPU to detect the need for non-global mappings and thus avoiding a
1532  * pagetable re-write after all the CPUs are booted. This check will be
1533  * anyway run on individual CPUs, allowing us to get the consistent
1534  * state once the SMP CPUs are up and thus make the switch to non-global
1535  * mappings if required.
1536  */
1537 bool kaslr_requires_kpti(void)
1538 {
1539 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1540 		return false;
1541 
1542 	/*
1543 	 * E0PD does a similar job to KPTI so can be used instead
1544 	 * where available.
1545 	 */
1546 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1547 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1548 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1549 						ID_AA64MMFR2_E0PD_SHIFT))
1550 			return false;
1551 	}
1552 
1553 	/*
1554 	 * Systems affected by Cavium erratum 24756 are incompatible
1555 	 * with KPTI.
1556 	 */
1557 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1558 		extern const struct midr_range cavium_erratum_27456_cpus[];
1559 
1560 		if (is_midr_in_range_list(read_cpuid_id(),
1561 					  cavium_erratum_27456_cpus))
1562 			return false;
1563 	}
1564 
1565 	return kaslr_offset() > 0;
1566 }
1567 
1568 static bool __meltdown_safe = true;
1569 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1570 
1571 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1572 				int scope)
1573 {
1574 	/* List of CPUs that are not vulnerable and don't need KPTI */
1575 	static const struct midr_range kpti_safe_list[] = {
1576 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1577 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1578 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1579 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1580 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1581 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1582 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1583 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1584 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1585 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1586 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1587 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1588 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1589 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1590 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1591 		{ /* sentinel */ }
1592 	};
1593 	char const *str = "kpti command line option";
1594 	bool meltdown_safe;
1595 
1596 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1597 
1598 	/* Defer to CPU feature registers */
1599 	if (has_cpuid_feature(entry, scope))
1600 		meltdown_safe = true;
1601 
1602 	if (!meltdown_safe)
1603 		__meltdown_safe = false;
1604 
1605 	/*
1606 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1607 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1608 	 * ends as well as you might imagine. Don't even try. We cannot rely
1609 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1610 	 * because cpucap detection order may change. However, since we know
1611 	 * affected CPUs are always in a homogeneous configuration, it is
1612 	 * safe to rely on this_cpu_has_cap() here.
1613 	 */
1614 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1615 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1616 		__kpti_forced = -1;
1617 	}
1618 
1619 	/* Useful for KASLR robustness */
1620 	if (kaslr_requires_kpti()) {
1621 		if (!__kpti_forced) {
1622 			str = "KASLR";
1623 			__kpti_forced = 1;
1624 		}
1625 	}
1626 
1627 	if (cpu_mitigations_off() && !__kpti_forced) {
1628 		str = "mitigations=off";
1629 		__kpti_forced = -1;
1630 	}
1631 
1632 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1633 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1634 		return false;
1635 	}
1636 
1637 	/* Forced? */
1638 	if (__kpti_forced) {
1639 		pr_info_once("kernel page table isolation forced %s by %s\n",
1640 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1641 		return __kpti_forced > 0;
1642 	}
1643 
1644 	return !meltdown_safe;
1645 }
1646 
1647 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1648 static void __nocfi
1649 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1650 {
1651 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1652 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1653 	kpti_remap_fn *remap_fn;
1654 
1655 	int cpu = smp_processor_id();
1656 
1657 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1658 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1659 
1660 		__this_cpu_write(this_cpu_vector, v);
1661 	}
1662 
1663 	/*
1664 	 * We don't need to rewrite the page-tables if either we've done
1665 	 * it already or we have KASLR enabled and therefore have not
1666 	 * created any global mappings at all.
1667 	 */
1668 	if (arm64_use_ng_mappings)
1669 		return;
1670 
1671 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1672 
1673 	cpu_install_idmap();
1674 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1675 	cpu_uninstall_idmap();
1676 
1677 	if (!cpu)
1678 		arm64_use_ng_mappings = true;
1679 }
1680 #else
1681 static void
1682 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1683 {
1684 }
1685 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1686 
1687 static int __init parse_kpti(char *str)
1688 {
1689 	bool enabled;
1690 	int ret = strtobool(str, &enabled);
1691 
1692 	if (ret)
1693 		return ret;
1694 
1695 	__kpti_forced = enabled ? 1 : -1;
1696 	return 0;
1697 }
1698 early_param("kpti", parse_kpti);
1699 
1700 #ifdef CONFIG_ARM64_HW_AFDBM
1701 static inline void __cpu_enable_hw_dbm(void)
1702 {
1703 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1704 
1705 	write_sysreg(tcr, tcr_el1);
1706 	isb();
1707 	local_flush_tlb_all();
1708 }
1709 
1710 static bool cpu_has_broken_dbm(void)
1711 {
1712 	/* List of CPUs which have broken DBM support. */
1713 	static const struct midr_range cpus[] = {
1714 #ifdef CONFIG_ARM64_ERRATUM_1024718
1715 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1716 		/* Kryo4xx Silver (rdpe => r1p0) */
1717 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1718 #endif
1719 #ifdef CONFIG_ARM64_ERRATUM_2051678
1720 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1721 #endif
1722 		{},
1723 	};
1724 
1725 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1726 }
1727 
1728 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1729 {
1730 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1731 	       !cpu_has_broken_dbm();
1732 }
1733 
1734 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1735 {
1736 	if (cpu_can_use_dbm(cap))
1737 		__cpu_enable_hw_dbm();
1738 }
1739 
1740 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1741 		       int __unused)
1742 {
1743 	static bool detected = false;
1744 	/*
1745 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1746 	 * run a mix of CPUs with and without the feature. So, we
1747 	 * unconditionally enable the capability to allow any late CPU
1748 	 * to use the feature. We only enable the control bits on the
1749 	 * CPU, if it actually supports.
1750 	 *
1751 	 * We have to make sure we print the "feature" detection only
1752 	 * when at least one CPU actually uses it. So check if this CPU
1753 	 * can actually use it and print the message exactly once.
1754 	 *
1755 	 * This is safe as all CPUs (including secondary CPUs - due to the
1756 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1757 	 * goes through the "matches" check exactly once. Also if a CPU
1758 	 * matches the criteria, it is guaranteed that the CPU will turn
1759 	 * the DBM on, as the capability is unconditionally enabled.
1760 	 */
1761 	if (!detected && cpu_can_use_dbm(cap)) {
1762 		detected = true;
1763 		pr_info("detected: Hardware dirty bit management\n");
1764 	}
1765 
1766 	return true;
1767 }
1768 
1769 #endif
1770 
1771 #ifdef CONFIG_ARM64_AMU_EXTN
1772 
1773 /*
1774  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1775  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1776  * information regarding all the events that it supports. When a CPU bit is
1777  * set in the cpumask, the user of this feature can only rely on the presence
1778  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1779  * counters are enabled or access to these counters is enabled by code
1780  * executed at higher exception levels (firmware).
1781  */
1782 static struct cpumask amu_cpus __read_mostly;
1783 
1784 bool cpu_has_amu_feat(int cpu)
1785 {
1786 	return cpumask_test_cpu(cpu, &amu_cpus);
1787 }
1788 
1789 int get_cpu_with_amu_feat(void)
1790 {
1791 	return cpumask_any(&amu_cpus);
1792 }
1793 
1794 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1795 {
1796 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1797 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1798 			smp_processor_id());
1799 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1800 		update_freq_counters_refs();
1801 	}
1802 }
1803 
1804 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1805 		    int __unused)
1806 {
1807 	/*
1808 	 * The AMU extension is a non-conflicting feature: the kernel can
1809 	 * safely run a mix of CPUs with and without support for the
1810 	 * activity monitors extension. Therefore, unconditionally enable
1811 	 * the capability to allow any late CPU to use the feature.
1812 	 *
1813 	 * With this feature unconditionally enabled, the cpu_enable
1814 	 * function will be called for all CPUs that match the criteria,
1815 	 * including secondary and hotplugged, marking this feature as
1816 	 * present on that respective CPU. The enable function will also
1817 	 * print a detection message.
1818 	 */
1819 
1820 	return true;
1821 }
1822 #else
1823 int get_cpu_with_amu_feat(void)
1824 {
1825 	return nr_cpu_ids;
1826 }
1827 #endif
1828 
1829 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1830 {
1831 	return is_kernel_in_hyp_mode();
1832 }
1833 
1834 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1835 {
1836 	/*
1837 	 * Copy register values that aren't redirected by hardware.
1838 	 *
1839 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1840 	 * this value to tpidr_el2 before we patch the code. Once we've done
1841 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1842 	 * do anything here.
1843 	 */
1844 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1845 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1846 }
1847 
1848 #ifdef CONFIG_ARM64_PAN
1849 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1850 {
1851 	/*
1852 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1853 	 * is discarded once we return from the exception.
1854 	 */
1855 	WARN_ON_ONCE(in_interrupt());
1856 
1857 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1858 	set_pstate_pan(1);
1859 }
1860 #endif /* CONFIG_ARM64_PAN */
1861 
1862 #ifdef CONFIG_ARM64_RAS_EXTN
1863 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1864 {
1865 	/* Firmware may have left a deferred SError in this register. */
1866 	write_sysreg_s(0, SYS_DISR_EL1);
1867 }
1868 #endif /* CONFIG_ARM64_RAS_EXTN */
1869 
1870 #ifdef CONFIG_ARM64_PTR_AUTH
1871 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1872 {
1873 	int boot_val, sec_val;
1874 
1875 	/* We don't expect to be called with SCOPE_SYSTEM */
1876 	WARN_ON(scope == SCOPE_SYSTEM);
1877 	/*
1878 	 * The ptr-auth feature levels are not intercompatible with lower
1879 	 * levels. Hence we must match ptr-auth feature level of the secondary
1880 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1881 	 * from the sanitised register whereas direct register read is done for
1882 	 * the secondary CPUs.
1883 	 * The sanitised feature state is guaranteed to match that of the
1884 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1885 	 * a chance to update the state, with the capability.
1886 	 */
1887 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1888 					       entry->field_pos, entry->sign);
1889 	if (scope & SCOPE_BOOT_CPU)
1890 		return boot_val >= entry->min_field_value;
1891 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1892 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1893 					      entry->field_pos, entry->sign);
1894 	return (sec_val >= entry->min_field_value) && (sec_val == boot_val);
1895 }
1896 
1897 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1898 				     int scope)
1899 {
1900 	bool api = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1901 	bool apa = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5], scope);
1902 	bool apa3 = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3], scope);
1903 
1904 	return apa || apa3 || api;
1905 }
1906 
1907 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1908 			     int __unused)
1909 {
1910 	bool gpi = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1911 	bool gpa = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5);
1912 	bool gpa3 = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3);
1913 
1914 	return gpa || gpa3 || gpi;
1915 }
1916 #endif /* CONFIG_ARM64_PTR_AUTH */
1917 
1918 #ifdef CONFIG_ARM64_E0PD
1919 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1920 {
1921 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1922 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1923 }
1924 #endif /* CONFIG_ARM64_E0PD */
1925 
1926 #ifdef CONFIG_ARM64_PSEUDO_NMI
1927 static bool enable_pseudo_nmi;
1928 
1929 static int __init early_enable_pseudo_nmi(char *p)
1930 {
1931 	return strtobool(p, &enable_pseudo_nmi);
1932 }
1933 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1934 
1935 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1936 				   int scope)
1937 {
1938 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1939 }
1940 #endif
1941 
1942 #ifdef CONFIG_ARM64_BTI
1943 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1944 {
1945 	/*
1946 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1947 	 * function entry points using BR is a requirement for
1948 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1949 	 * So, be strict and forbid other BRs using other registers to
1950 	 * jump onto a PACIxSP instruction:
1951 	 */
1952 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1953 	isb();
1954 }
1955 #endif /* CONFIG_ARM64_BTI */
1956 
1957 #ifdef CONFIG_ARM64_MTE
1958 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1959 {
1960 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
1961 	isb();
1962 
1963 	/*
1964 	 * Clear the tags in the zero page. This needs to be done via the
1965 	 * linear map which has the Tagged attribute.
1966 	 */
1967 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1968 		mte_clear_page_tags(lm_alias(empty_zero_page));
1969 
1970 	kasan_init_hw_tags_cpu();
1971 }
1972 #endif /* CONFIG_ARM64_MTE */
1973 
1974 #ifdef CONFIG_KVM
1975 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1976 {
1977 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1978 		return false;
1979 
1980 	if (is_kernel_in_hyp_mode()) {
1981 		pr_warn("Protected KVM not available with VHE\n");
1982 		return false;
1983 	}
1984 
1985 	return true;
1986 }
1987 #endif /* CONFIG_KVM */
1988 
1989 /* Internal helper functions to match cpu capability type */
1990 static bool
1991 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1992 {
1993 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1994 }
1995 
1996 static bool
1997 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1998 {
1999 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
2000 }
2001 
2002 static bool
2003 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
2004 {
2005 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
2006 }
2007 
2008 static const struct arm64_cpu_capabilities arm64_features[] = {
2009 	{
2010 		.desc = "GIC system register CPU interface",
2011 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
2012 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2013 		.matches = has_useable_gicv3_cpuif,
2014 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2015 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2016 		.field_width = 4,
2017 		.sign = FTR_UNSIGNED,
2018 		.min_field_value = 1,
2019 	},
2020 	{
2021 		.desc = "Enhanced Counter Virtualization",
2022 		.capability = ARM64_HAS_ECV,
2023 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2024 		.matches = has_cpuid_feature,
2025 		.sys_reg = SYS_ID_AA64MMFR0_EL1,
2026 		.field_pos = ID_AA64MMFR0_ECV_SHIFT,
2027 		.field_width = 4,
2028 		.sign = FTR_UNSIGNED,
2029 		.min_field_value = 1,
2030 	},
2031 #ifdef CONFIG_ARM64_PAN
2032 	{
2033 		.desc = "Privileged Access Never",
2034 		.capability = ARM64_HAS_PAN,
2035 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2036 		.matches = has_cpuid_feature,
2037 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2038 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
2039 		.field_width = 4,
2040 		.sign = FTR_UNSIGNED,
2041 		.min_field_value = 1,
2042 		.cpu_enable = cpu_enable_pan,
2043 	},
2044 #endif /* CONFIG_ARM64_PAN */
2045 #ifdef CONFIG_ARM64_EPAN
2046 	{
2047 		.desc = "Enhanced Privileged Access Never",
2048 		.capability = ARM64_HAS_EPAN,
2049 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2050 		.matches = has_cpuid_feature,
2051 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2052 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
2053 		.field_width = 4,
2054 		.sign = FTR_UNSIGNED,
2055 		.min_field_value = 3,
2056 	},
2057 #endif /* CONFIG_ARM64_EPAN */
2058 #ifdef CONFIG_ARM64_LSE_ATOMICS
2059 	{
2060 		.desc = "LSE atomic instructions",
2061 		.capability = ARM64_HAS_LSE_ATOMICS,
2062 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2063 		.matches = has_cpuid_feature,
2064 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2065 		.field_pos = ID_AA64ISAR0_EL1_ATOMIC_SHIFT,
2066 		.field_width = 4,
2067 		.sign = FTR_UNSIGNED,
2068 		.min_field_value = 2,
2069 	},
2070 #endif /* CONFIG_ARM64_LSE_ATOMICS */
2071 	{
2072 		.desc = "Software prefetching using PRFM",
2073 		.capability = ARM64_HAS_NO_HW_PREFETCH,
2074 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2075 		.matches = has_no_hw_prefetch,
2076 	},
2077 	{
2078 		.desc = "Virtualization Host Extensions",
2079 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
2080 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2081 		.matches = runs_at_el2,
2082 		.cpu_enable = cpu_copy_el2regs,
2083 	},
2084 	{
2085 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2086 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2087 		.matches = has_32bit_el0,
2088 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2089 		.sign = FTR_UNSIGNED,
2090 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
2091 		.field_width = 4,
2092 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2093 	},
2094 #ifdef CONFIG_KVM
2095 	{
2096 		.desc = "32-bit EL1 Support",
2097 		.capability = ARM64_HAS_32BIT_EL1,
2098 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2099 		.matches = has_cpuid_feature,
2100 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2101 		.sign = FTR_UNSIGNED,
2102 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
2103 		.field_width = 4,
2104 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2105 	},
2106 	{
2107 		.desc = "Protected KVM",
2108 		.capability = ARM64_KVM_PROTECTED_MODE,
2109 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2110 		.matches = is_kvm_protected_mode,
2111 	},
2112 #endif
2113 	{
2114 		.desc = "Kernel page table isolation (KPTI)",
2115 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2116 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2117 		/*
2118 		 * The ID feature fields below are used to indicate that
2119 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2120 		 * more details.
2121 		 */
2122 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2123 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
2124 		.field_width = 4,
2125 		.min_field_value = 1,
2126 		.matches = unmap_kernel_at_el0,
2127 		.cpu_enable = kpti_install_ng_mappings,
2128 	},
2129 	{
2130 		/* FP/SIMD is not implemented */
2131 		.capability = ARM64_HAS_NO_FPSIMD,
2132 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2133 		.min_field_value = 0,
2134 		.matches = has_no_fpsimd,
2135 	},
2136 #ifdef CONFIG_ARM64_PMEM
2137 	{
2138 		.desc = "Data cache clean to Point of Persistence",
2139 		.capability = ARM64_HAS_DCPOP,
2140 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2141 		.matches = has_cpuid_feature,
2142 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2143 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2144 		.field_width = 4,
2145 		.min_field_value = 1,
2146 	},
2147 	{
2148 		.desc = "Data cache clean to Point of Deep Persistence",
2149 		.capability = ARM64_HAS_DCPODP,
2150 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2151 		.matches = has_cpuid_feature,
2152 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2153 		.sign = FTR_UNSIGNED,
2154 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2155 		.field_width = 4,
2156 		.min_field_value = 2,
2157 	},
2158 #endif
2159 #ifdef CONFIG_ARM64_SVE
2160 	{
2161 		.desc = "Scalable Vector Extension",
2162 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2163 		.capability = ARM64_SVE,
2164 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2165 		.sign = FTR_UNSIGNED,
2166 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2167 		.field_width = 4,
2168 		.min_field_value = ID_AA64PFR0_SVE,
2169 		.matches = has_cpuid_feature,
2170 		.cpu_enable = sve_kernel_enable,
2171 	},
2172 #endif /* CONFIG_ARM64_SVE */
2173 #ifdef CONFIG_ARM64_RAS_EXTN
2174 	{
2175 		.desc = "RAS Extension Support",
2176 		.capability = ARM64_HAS_RAS_EXTN,
2177 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2178 		.matches = has_cpuid_feature,
2179 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2180 		.sign = FTR_UNSIGNED,
2181 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2182 		.field_width = 4,
2183 		.min_field_value = ID_AA64PFR0_RAS_V1,
2184 		.cpu_enable = cpu_clear_disr,
2185 	},
2186 #endif /* CONFIG_ARM64_RAS_EXTN */
2187 #ifdef CONFIG_ARM64_AMU_EXTN
2188 	{
2189 		/*
2190 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2191 		 * Therefore, don't provide .desc as we don't want the detection
2192 		 * message to be shown until at least one CPU is detected to
2193 		 * support the feature.
2194 		 */
2195 		.capability = ARM64_HAS_AMU_EXTN,
2196 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2197 		.matches = has_amu,
2198 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2199 		.sign = FTR_UNSIGNED,
2200 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2201 		.field_width = 4,
2202 		.min_field_value = ID_AA64PFR0_AMU,
2203 		.cpu_enable = cpu_amu_enable,
2204 	},
2205 #endif /* CONFIG_ARM64_AMU_EXTN */
2206 	{
2207 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2208 		.capability = ARM64_HAS_CACHE_IDC,
2209 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2210 		.matches = has_cache_idc,
2211 		.cpu_enable = cpu_emulate_effective_ctr,
2212 	},
2213 	{
2214 		.desc = "Instruction cache invalidation not required for I/D coherence",
2215 		.capability = ARM64_HAS_CACHE_DIC,
2216 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2217 		.matches = has_cache_dic,
2218 	},
2219 	{
2220 		.desc = "Stage-2 Force Write-Back",
2221 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2222 		.capability = ARM64_HAS_STAGE2_FWB,
2223 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2224 		.sign = FTR_UNSIGNED,
2225 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2226 		.field_width = 4,
2227 		.min_field_value = 1,
2228 		.matches = has_cpuid_feature,
2229 	},
2230 	{
2231 		.desc = "ARMv8.4 Translation Table Level",
2232 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2233 		.capability = ARM64_HAS_ARMv8_4_TTL,
2234 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2235 		.sign = FTR_UNSIGNED,
2236 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2237 		.field_width = 4,
2238 		.min_field_value = 1,
2239 		.matches = has_cpuid_feature,
2240 	},
2241 	{
2242 		.desc = "TLB range maintenance instructions",
2243 		.capability = ARM64_HAS_TLB_RANGE,
2244 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2245 		.matches = has_cpuid_feature,
2246 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2247 		.field_pos = ID_AA64ISAR0_EL1_TLB_SHIFT,
2248 		.field_width = 4,
2249 		.sign = FTR_UNSIGNED,
2250 		.min_field_value = ID_AA64ISAR0_EL1_TLB_RANGE,
2251 	},
2252 #ifdef CONFIG_ARM64_HW_AFDBM
2253 	{
2254 		/*
2255 		 * Since we turn this on always, we don't want the user to
2256 		 * think that the feature is available when it may not be.
2257 		 * So hide the description.
2258 		 *
2259 		 * .desc = "Hardware pagetable Dirty Bit Management",
2260 		 *
2261 		 */
2262 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2263 		.capability = ARM64_HW_DBM,
2264 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2265 		.sign = FTR_UNSIGNED,
2266 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2267 		.field_width = 4,
2268 		.min_field_value = 2,
2269 		.matches = has_hw_dbm,
2270 		.cpu_enable = cpu_enable_hw_dbm,
2271 	},
2272 #endif
2273 	{
2274 		.desc = "CRC32 instructions",
2275 		.capability = ARM64_HAS_CRC32,
2276 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2277 		.matches = has_cpuid_feature,
2278 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2279 		.field_pos = ID_AA64ISAR0_EL1_CRC32_SHIFT,
2280 		.field_width = 4,
2281 		.min_field_value = 1,
2282 	},
2283 	{
2284 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2285 		.capability = ARM64_SSBS,
2286 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2287 		.matches = has_cpuid_feature,
2288 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2289 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2290 		.field_width = 4,
2291 		.sign = FTR_UNSIGNED,
2292 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2293 	},
2294 #ifdef CONFIG_ARM64_CNP
2295 	{
2296 		.desc = "Common not Private translations",
2297 		.capability = ARM64_HAS_CNP,
2298 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2299 		.matches = has_useable_cnp,
2300 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2301 		.sign = FTR_UNSIGNED,
2302 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2303 		.field_width = 4,
2304 		.min_field_value = 1,
2305 		.cpu_enable = cpu_enable_cnp,
2306 	},
2307 #endif
2308 	{
2309 		.desc = "Speculation barrier (SB)",
2310 		.capability = ARM64_HAS_SB,
2311 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2312 		.matches = has_cpuid_feature,
2313 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2314 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2315 		.field_width = 4,
2316 		.sign = FTR_UNSIGNED,
2317 		.min_field_value = 1,
2318 	},
2319 #ifdef CONFIG_ARM64_PTR_AUTH
2320 	{
2321 		.desc = "Address authentication (architected QARMA5 algorithm)",
2322 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5,
2323 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2324 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2325 		.sign = FTR_UNSIGNED,
2326 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2327 		.field_width = 4,
2328 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2329 		.matches = has_address_auth_cpucap,
2330 	},
2331 	{
2332 		.desc = "Address authentication (architected QARMA3 algorithm)",
2333 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3,
2334 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2335 		.sys_reg = SYS_ID_AA64ISAR2_EL1,
2336 		.sign = FTR_UNSIGNED,
2337 		.field_pos = ID_AA64ISAR2_APA3_SHIFT,
2338 		.field_width = 4,
2339 		.min_field_value = ID_AA64ISAR2_APA3_ARCHITECTED,
2340 		.matches = has_address_auth_cpucap,
2341 	},
2342 	{
2343 		.desc = "Address authentication (IMP DEF algorithm)",
2344 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2345 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2346 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2347 		.sign = FTR_UNSIGNED,
2348 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2349 		.field_width = 4,
2350 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2351 		.matches = has_address_auth_cpucap,
2352 	},
2353 	{
2354 		.capability = ARM64_HAS_ADDRESS_AUTH,
2355 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2356 		.matches = has_address_auth_metacap,
2357 	},
2358 	{
2359 		.desc = "Generic authentication (architected QARMA5 algorithm)",
2360 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5,
2361 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2362 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2363 		.sign = FTR_UNSIGNED,
2364 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2365 		.field_width = 4,
2366 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2367 		.matches = has_cpuid_feature,
2368 	},
2369 	{
2370 		.desc = "Generic authentication (architected QARMA3 algorithm)",
2371 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3,
2372 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2373 		.sys_reg = SYS_ID_AA64ISAR2_EL1,
2374 		.sign = FTR_UNSIGNED,
2375 		.field_pos = ID_AA64ISAR2_GPA3_SHIFT,
2376 		.field_width = 4,
2377 		.min_field_value = ID_AA64ISAR2_GPA3_ARCHITECTED,
2378 		.matches = has_cpuid_feature,
2379 	},
2380 	{
2381 		.desc = "Generic authentication (IMP DEF algorithm)",
2382 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2383 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2384 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2385 		.sign = FTR_UNSIGNED,
2386 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2387 		.field_width = 4,
2388 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2389 		.matches = has_cpuid_feature,
2390 	},
2391 	{
2392 		.capability = ARM64_HAS_GENERIC_AUTH,
2393 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2394 		.matches = has_generic_auth,
2395 	},
2396 #endif /* CONFIG_ARM64_PTR_AUTH */
2397 #ifdef CONFIG_ARM64_PSEUDO_NMI
2398 	{
2399 		/*
2400 		 * Depends on having GICv3
2401 		 */
2402 		.desc = "IRQ priority masking",
2403 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2404 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2405 		.matches = can_use_gic_priorities,
2406 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2407 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2408 		.field_width = 4,
2409 		.sign = FTR_UNSIGNED,
2410 		.min_field_value = 1,
2411 	},
2412 #endif
2413 #ifdef CONFIG_ARM64_E0PD
2414 	{
2415 		.desc = "E0PD",
2416 		.capability = ARM64_HAS_E0PD,
2417 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2418 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2419 		.sign = FTR_UNSIGNED,
2420 		.field_width = 4,
2421 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2422 		.matches = has_cpuid_feature,
2423 		.min_field_value = 1,
2424 		.cpu_enable = cpu_enable_e0pd,
2425 	},
2426 #endif
2427 #ifdef CONFIG_ARCH_RANDOM
2428 	{
2429 		.desc = "Random Number Generator",
2430 		.capability = ARM64_HAS_RNG,
2431 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2432 		.matches = has_cpuid_feature,
2433 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2434 		.field_pos = ID_AA64ISAR0_EL1_RNDR_SHIFT,
2435 		.field_width = 4,
2436 		.sign = FTR_UNSIGNED,
2437 		.min_field_value = 1,
2438 	},
2439 #endif
2440 #ifdef CONFIG_ARM64_BTI
2441 	{
2442 		.desc = "Branch Target Identification",
2443 		.capability = ARM64_BTI,
2444 #ifdef CONFIG_ARM64_BTI_KERNEL
2445 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2446 #else
2447 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2448 #endif
2449 		.matches = has_cpuid_feature,
2450 		.cpu_enable = bti_enable,
2451 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2452 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2453 		.field_width = 4,
2454 		.min_field_value = ID_AA64PFR1_BT_BTI,
2455 		.sign = FTR_UNSIGNED,
2456 	},
2457 #endif
2458 #ifdef CONFIG_ARM64_MTE
2459 	{
2460 		.desc = "Memory Tagging Extension",
2461 		.capability = ARM64_MTE,
2462 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2463 		.matches = has_cpuid_feature,
2464 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2465 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2466 		.field_width = 4,
2467 		.min_field_value = ID_AA64PFR1_MTE,
2468 		.sign = FTR_UNSIGNED,
2469 		.cpu_enable = cpu_enable_mte,
2470 	},
2471 	{
2472 		.desc = "Asymmetric MTE Tag Check Fault",
2473 		.capability = ARM64_MTE_ASYMM,
2474 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2475 		.matches = has_cpuid_feature,
2476 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2477 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2478 		.field_width = 4,
2479 		.min_field_value = ID_AA64PFR1_MTE_ASYMM,
2480 		.sign = FTR_UNSIGNED,
2481 	},
2482 #endif /* CONFIG_ARM64_MTE */
2483 	{
2484 		.desc = "RCpc load-acquire (LDAPR)",
2485 		.capability = ARM64_HAS_LDAPR,
2486 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2487 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2488 		.sign = FTR_UNSIGNED,
2489 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2490 		.field_width = 4,
2491 		.matches = has_cpuid_feature,
2492 		.min_field_value = 1,
2493 	},
2494 #ifdef CONFIG_ARM64_SME
2495 	{
2496 		.desc = "Scalable Matrix Extension",
2497 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2498 		.capability = ARM64_SME,
2499 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2500 		.sign = FTR_UNSIGNED,
2501 		.field_pos = ID_AA64PFR1_SME_SHIFT,
2502 		.field_width = 4,
2503 		.min_field_value = ID_AA64PFR1_SME,
2504 		.matches = has_cpuid_feature,
2505 		.cpu_enable = sme_kernel_enable,
2506 	},
2507 	/* FA64 should be sorted after the base SME capability */
2508 	{
2509 		.desc = "FA64",
2510 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2511 		.capability = ARM64_SME_FA64,
2512 		.sys_reg = SYS_ID_AA64SMFR0_EL1,
2513 		.sign = FTR_UNSIGNED,
2514 		.field_pos = ID_AA64SMFR0_FA64_SHIFT,
2515 		.field_width = 1,
2516 		.min_field_value = ID_AA64SMFR0_FA64,
2517 		.matches = has_cpuid_feature,
2518 		.cpu_enable = fa64_kernel_enable,
2519 	},
2520 #endif /* CONFIG_ARM64_SME */
2521 	{
2522 		.desc = "WFx with timeout",
2523 		.capability = ARM64_HAS_WFXT,
2524 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2525 		.sys_reg = SYS_ID_AA64ISAR2_EL1,
2526 		.sign = FTR_UNSIGNED,
2527 		.field_pos = ID_AA64ISAR2_WFXT_SHIFT,
2528 		.field_width = 4,
2529 		.matches = has_cpuid_feature,
2530 		.min_field_value = ID_AA64ISAR2_WFXT_SUPPORTED,
2531 	},
2532 	{},
2533 };
2534 
2535 #define HWCAP_CPUID_MATCH(reg, field, width, s, min_value)			\
2536 		.matches = has_cpuid_feature,					\
2537 		.sys_reg = reg,							\
2538 		.field_pos = field,						\
2539 		.field_width = width,						\
2540 		.sign = s,							\
2541 		.min_field_value = min_value,
2542 
2543 #define __HWCAP_CAP(name, cap_type, cap)					\
2544 		.desc = name,							\
2545 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2546 		.hwcap_type = cap_type,						\
2547 		.hwcap = cap,							\
2548 
2549 #define HWCAP_CAP(reg, field, width, s, min_value, cap_type, cap)		\
2550 	{									\
2551 		__HWCAP_CAP(#cap, cap_type, cap)				\
2552 		HWCAP_CPUID_MATCH(reg, field, width, s, min_value) 		\
2553 	}
2554 
2555 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2556 	{									\
2557 		__HWCAP_CAP(#cap, cap_type, cap)				\
2558 		.matches = cpucap_multi_entry_cap_matches,			\
2559 		.match_list = list,						\
2560 	}
2561 
2562 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2563 	{									\
2564 		__HWCAP_CAP(#cap, cap_type, cap)				\
2565 		.matches = match,						\
2566 	}
2567 
2568 #ifdef CONFIG_ARM64_PTR_AUTH
2569 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2570 	{
2571 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2572 				  4, FTR_UNSIGNED,
2573 				  ID_AA64ISAR1_APA_ARCHITECTED)
2574 	},
2575 	{
2576 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_APA3_SHIFT,
2577 				  4, FTR_UNSIGNED, ID_AA64ISAR2_APA3_ARCHITECTED)
2578 	},
2579 	{
2580 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2581 				  4, FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2582 	},
2583 	{},
2584 };
2585 
2586 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2587 	{
2588 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2589 				  4, FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2590 	},
2591 	{
2592 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_GPA3_SHIFT,
2593 				  4, FTR_UNSIGNED, ID_AA64ISAR2_GPA3_ARCHITECTED)
2594 	},
2595 	{
2596 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2597 				  4, FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2598 	},
2599 	{},
2600 };
2601 #endif
2602 
2603 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2604 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_AES_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2605 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_AES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2606 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SHA1_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2607 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SHA2_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2608 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SHA2_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2609 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_CRC32_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2610 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_ATOMIC_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2611 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_RDM_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2612 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SHA3_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2613 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SM3_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2614 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_SM4_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2615 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_DP_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2616 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_FHM_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2617 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_TS_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2618 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_TS_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2619 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_RNDR_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2620 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, 4, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2621 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, 4, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2622 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, 4, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2623 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, 4, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2624 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, 4, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2625 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2626 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2627 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2628 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2629 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2630 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2631 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2632 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2633 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2634 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2635 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2636 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2637 #ifdef CONFIG_ARM64_SVE
2638 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2639 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2640 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2641 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2642 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2643 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2644 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2645 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2646 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2647 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2648 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, 4, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2649 #endif
2650 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2651 #ifdef CONFIG_ARM64_BTI
2652 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2653 #endif
2654 #ifdef CONFIG_ARM64_PTR_AUTH
2655 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2656 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2657 #endif
2658 #ifdef CONFIG_ARM64_MTE
2659 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2660 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_MTE_ASYMM, CAP_HWCAP, KERNEL_HWCAP_MTE3),
2661 #endif /* CONFIG_ARM64_MTE */
2662 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2663 	HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
2664 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2665 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_WFXT_SHIFT, 4, FTR_UNSIGNED, ID_AA64ISAR2_WFXT_SUPPORTED, CAP_HWCAP, KERNEL_HWCAP_WFXT),
2666 #ifdef CONFIG_ARM64_SME
2667 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SME_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_SME, CAP_HWCAP, KERNEL_HWCAP_SME),
2668 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_FA64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_FA64, CAP_HWCAP, KERNEL_HWCAP_SME_FA64),
2669 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_I16I64_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_I16I64, CAP_HWCAP, KERNEL_HWCAP_SME_I16I64),
2670 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_F64F64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_F64F64, CAP_HWCAP, KERNEL_HWCAP_SME_F64F64),
2671 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_I8I32_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_I8I32, CAP_HWCAP, KERNEL_HWCAP_SME_I8I32),
2672 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_F16F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_F16F32, CAP_HWCAP, KERNEL_HWCAP_SME_F16F32),
2673 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_B16F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_B16F32, CAP_HWCAP, KERNEL_HWCAP_SME_B16F32),
2674 	HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_F32F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_F32F32, CAP_HWCAP, KERNEL_HWCAP_SME_F32F32),
2675 #endif /* CONFIG_ARM64_SME */
2676 	{},
2677 };
2678 
2679 #ifdef CONFIG_COMPAT
2680 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2681 {
2682 	/*
2683 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2684 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2685 	 * check is future proof, by making sure value is non-zero.
2686 	 */
2687 	u32 mvfr1;
2688 
2689 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2690 	if (scope == SCOPE_SYSTEM)
2691 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2692 	else
2693 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2694 
2695 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2696 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2697 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2698 }
2699 #endif
2700 
2701 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2702 #ifdef CONFIG_COMPAT
2703 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2704 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2705 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2706 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2707 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2708 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2709 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2710 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2711 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2712 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2713 #endif
2714 	{},
2715 };
2716 
2717 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2718 {
2719 	switch (cap->hwcap_type) {
2720 	case CAP_HWCAP:
2721 		cpu_set_feature(cap->hwcap);
2722 		break;
2723 #ifdef CONFIG_COMPAT
2724 	case CAP_COMPAT_HWCAP:
2725 		compat_elf_hwcap |= (u32)cap->hwcap;
2726 		break;
2727 	case CAP_COMPAT_HWCAP2:
2728 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2729 		break;
2730 #endif
2731 	default:
2732 		WARN_ON(1);
2733 		break;
2734 	}
2735 }
2736 
2737 /* Check if we have a particular HWCAP enabled */
2738 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2739 {
2740 	bool rc;
2741 
2742 	switch (cap->hwcap_type) {
2743 	case CAP_HWCAP:
2744 		rc = cpu_have_feature(cap->hwcap);
2745 		break;
2746 #ifdef CONFIG_COMPAT
2747 	case CAP_COMPAT_HWCAP:
2748 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2749 		break;
2750 	case CAP_COMPAT_HWCAP2:
2751 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2752 		break;
2753 #endif
2754 	default:
2755 		WARN_ON(1);
2756 		rc = false;
2757 	}
2758 
2759 	return rc;
2760 }
2761 
2762 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2763 {
2764 	/* We support emulation of accesses to CPU ID feature registers */
2765 	cpu_set_named_feature(CPUID);
2766 	for (; hwcaps->matches; hwcaps++)
2767 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2768 			cap_set_elf_hwcap(hwcaps);
2769 }
2770 
2771 static void update_cpu_capabilities(u16 scope_mask)
2772 {
2773 	int i;
2774 	const struct arm64_cpu_capabilities *caps;
2775 
2776 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2777 	for (i = 0; i < ARM64_NCAPS; i++) {
2778 		caps = cpu_hwcaps_ptrs[i];
2779 		if (!caps || !(caps->type & scope_mask) ||
2780 		    cpus_have_cap(caps->capability) ||
2781 		    !caps->matches(caps, cpucap_default_scope(caps)))
2782 			continue;
2783 
2784 		if (caps->desc)
2785 			pr_info("detected: %s\n", caps->desc);
2786 		cpus_set_cap(caps->capability);
2787 
2788 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2789 			set_bit(caps->capability, boot_capabilities);
2790 	}
2791 }
2792 
2793 /*
2794  * Enable all the available capabilities on this CPU. The capabilities
2795  * with BOOT_CPU scope are handled separately and hence skipped here.
2796  */
2797 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2798 {
2799 	int i;
2800 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2801 
2802 	for_each_available_cap(i) {
2803 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2804 
2805 		if (WARN_ON(!cap))
2806 			continue;
2807 
2808 		if (!(cap->type & non_boot_scope))
2809 			continue;
2810 
2811 		if (cap->cpu_enable)
2812 			cap->cpu_enable(cap);
2813 	}
2814 	return 0;
2815 }
2816 
2817 /*
2818  * Run through the enabled capabilities and enable() it on all active
2819  * CPUs
2820  */
2821 static void __init enable_cpu_capabilities(u16 scope_mask)
2822 {
2823 	int i;
2824 	const struct arm64_cpu_capabilities *caps;
2825 	bool boot_scope;
2826 
2827 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2828 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2829 
2830 	for (i = 0; i < ARM64_NCAPS; i++) {
2831 		unsigned int num;
2832 
2833 		caps = cpu_hwcaps_ptrs[i];
2834 		if (!caps || !(caps->type & scope_mask))
2835 			continue;
2836 		num = caps->capability;
2837 		if (!cpus_have_cap(num))
2838 			continue;
2839 
2840 		/* Ensure cpus_have_const_cap(num) works */
2841 		static_branch_enable(&cpu_hwcap_keys[num]);
2842 
2843 		if (boot_scope && caps->cpu_enable)
2844 			/*
2845 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2846 			 * before any secondary CPU boots. Thus, each secondary
2847 			 * will enable the capability as appropriate via
2848 			 * check_local_cpu_capabilities(). The only exception is
2849 			 * the boot CPU, for which the capability must be
2850 			 * enabled here. This approach avoids costly
2851 			 * stop_machine() calls for this case.
2852 			 */
2853 			caps->cpu_enable(caps);
2854 	}
2855 
2856 	/*
2857 	 * For all non-boot scope capabilities, use stop_machine()
2858 	 * as it schedules the work allowing us to modify PSTATE,
2859 	 * instead of on_each_cpu() which uses an IPI, giving us a
2860 	 * PSTATE that disappears when we return.
2861 	 */
2862 	if (!boot_scope)
2863 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2864 			     NULL, cpu_online_mask);
2865 }
2866 
2867 /*
2868  * Run through the list of capabilities to check for conflicts.
2869  * If the system has already detected a capability, take necessary
2870  * action on this CPU.
2871  */
2872 static void verify_local_cpu_caps(u16 scope_mask)
2873 {
2874 	int i;
2875 	bool cpu_has_cap, system_has_cap;
2876 	const struct arm64_cpu_capabilities *caps;
2877 
2878 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2879 
2880 	for (i = 0; i < ARM64_NCAPS; i++) {
2881 		caps = cpu_hwcaps_ptrs[i];
2882 		if (!caps || !(caps->type & scope_mask))
2883 			continue;
2884 
2885 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2886 		system_has_cap = cpus_have_cap(caps->capability);
2887 
2888 		if (system_has_cap) {
2889 			/*
2890 			 * Check if the new CPU misses an advertised feature,
2891 			 * which is not safe to miss.
2892 			 */
2893 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2894 				break;
2895 			/*
2896 			 * We have to issue cpu_enable() irrespective of
2897 			 * whether the CPU has it or not, as it is enabeld
2898 			 * system wide. It is upto the call back to take
2899 			 * appropriate action on this CPU.
2900 			 */
2901 			if (caps->cpu_enable)
2902 				caps->cpu_enable(caps);
2903 		} else {
2904 			/*
2905 			 * Check if the CPU has this capability if it isn't
2906 			 * safe to have when the system doesn't.
2907 			 */
2908 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2909 				break;
2910 		}
2911 	}
2912 
2913 	if (i < ARM64_NCAPS) {
2914 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2915 			smp_processor_id(), caps->capability,
2916 			caps->desc, system_has_cap, cpu_has_cap);
2917 
2918 		if (cpucap_panic_on_conflict(caps))
2919 			cpu_panic_kernel();
2920 		else
2921 			cpu_die_early();
2922 	}
2923 }
2924 
2925 /*
2926  * Check for CPU features that are used in early boot
2927  * based on the Boot CPU value.
2928  */
2929 static void check_early_cpu_features(void)
2930 {
2931 	verify_cpu_asid_bits();
2932 
2933 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2934 }
2935 
2936 static void
2937 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2938 {
2939 
2940 	for (; caps->matches; caps++)
2941 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2942 			pr_crit("CPU%d: missing HWCAP: %s\n",
2943 					smp_processor_id(), caps->desc);
2944 			cpu_die_early();
2945 		}
2946 }
2947 
2948 static void verify_local_elf_hwcaps(void)
2949 {
2950 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2951 
2952 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2953 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2954 }
2955 
2956 static void verify_sve_features(void)
2957 {
2958 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2959 	u64 zcr = read_zcr_features();
2960 
2961 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2962 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2963 
2964 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SVE)) {
2965 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2966 			smp_processor_id());
2967 		cpu_die_early();
2968 	}
2969 
2970 	/* Add checks on other ZCR bits here if necessary */
2971 }
2972 
2973 static void verify_sme_features(void)
2974 {
2975 	u64 safe_smcr = read_sanitised_ftr_reg(SYS_SMCR_EL1);
2976 	u64 smcr = read_smcr_features();
2977 
2978 	unsigned int safe_len = safe_smcr & SMCR_ELx_LEN_MASK;
2979 	unsigned int len = smcr & SMCR_ELx_LEN_MASK;
2980 
2981 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SME)) {
2982 		pr_crit("CPU%d: SME: vector length support mismatch\n",
2983 			smp_processor_id());
2984 		cpu_die_early();
2985 	}
2986 
2987 	/* Add checks on other SMCR bits here if necessary */
2988 }
2989 
2990 static void verify_hyp_capabilities(void)
2991 {
2992 	u64 safe_mmfr1, mmfr0, mmfr1;
2993 	int parange, ipa_max;
2994 	unsigned int safe_vmid_bits, vmid_bits;
2995 
2996 	if (!IS_ENABLED(CONFIG_KVM))
2997 		return;
2998 
2999 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
3000 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
3001 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
3002 
3003 	/* Verify VMID bits */
3004 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
3005 	vmid_bits = get_vmid_bits(mmfr1);
3006 	if (vmid_bits < safe_vmid_bits) {
3007 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
3008 		cpu_die_early();
3009 	}
3010 
3011 	/* Verify IPA range */
3012 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
3013 				ID_AA64MMFR0_PARANGE_SHIFT);
3014 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
3015 	if (ipa_max < get_kvm_ipa_limit()) {
3016 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
3017 		cpu_die_early();
3018 	}
3019 }
3020 
3021 /*
3022  * Run through the enabled system capabilities and enable() it on this CPU.
3023  * The capabilities were decided based on the available CPUs at the boot time.
3024  * Any new CPU should match the system wide status of the capability. If the
3025  * new CPU doesn't have a capability which the system now has enabled, we
3026  * cannot do anything to fix it up and could cause unexpected failures. So
3027  * we park the CPU.
3028  */
3029 static void verify_local_cpu_capabilities(void)
3030 {
3031 	/*
3032 	 * The capabilities with SCOPE_BOOT_CPU are checked from
3033 	 * check_early_cpu_features(), as they need to be verified
3034 	 * on all secondary CPUs.
3035 	 */
3036 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3037 	verify_local_elf_hwcaps();
3038 
3039 	if (system_supports_sve())
3040 		verify_sve_features();
3041 
3042 	if (system_supports_sme())
3043 		verify_sme_features();
3044 
3045 	if (is_hyp_mode_available())
3046 		verify_hyp_capabilities();
3047 }
3048 
3049 void check_local_cpu_capabilities(void)
3050 {
3051 	/*
3052 	 * All secondary CPUs should conform to the early CPU features
3053 	 * in use by the kernel based on boot CPU.
3054 	 */
3055 	check_early_cpu_features();
3056 
3057 	/*
3058 	 * If we haven't finalised the system capabilities, this CPU gets
3059 	 * a chance to update the errata work arounds and local features.
3060 	 * Otherwise, this CPU should verify that it has all the system
3061 	 * advertised capabilities.
3062 	 */
3063 	if (!system_capabilities_finalized())
3064 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
3065 	else
3066 		verify_local_cpu_capabilities();
3067 }
3068 
3069 static void __init setup_boot_cpu_capabilities(void)
3070 {
3071 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
3072 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
3073 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
3074 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
3075 }
3076 
3077 bool this_cpu_has_cap(unsigned int n)
3078 {
3079 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
3080 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
3081 
3082 		if (cap)
3083 			return cap->matches(cap, SCOPE_LOCAL_CPU);
3084 	}
3085 
3086 	return false;
3087 }
3088 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
3089 
3090 /*
3091  * This helper function is used in a narrow window when,
3092  * - The system wide safe registers are set with all the SMP CPUs and,
3093  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
3094  * In all other cases cpus_have_{const_}cap() should be used.
3095  */
3096 static bool __maybe_unused __system_matches_cap(unsigned int n)
3097 {
3098 	if (n < ARM64_NCAPS) {
3099 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
3100 
3101 		if (cap)
3102 			return cap->matches(cap, SCOPE_SYSTEM);
3103 	}
3104 	return false;
3105 }
3106 
3107 void cpu_set_feature(unsigned int num)
3108 {
3109 	WARN_ON(num >= MAX_CPU_FEATURES);
3110 	elf_hwcap |= BIT(num);
3111 }
3112 EXPORT_SYMBOL_GPL(cpu_set_feature);
3113 
3114 bool cpu_have_feature(unsigned int num)
3115 {
3116 	WARN_ON(num >= MAX_CPU_FEATURES);
3117 	return elf_hwcap & BIT(num);
3118 }
3119 EXPORT_SYMBOL_GPL(cpu_have_feature);
3120 
3121 unsigned long cpu_get_elf_hwcap(void)
3122 {
3123 	/*
3124 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
3125 	 * note that for userspace compatibility we guarantee that bits 62
3126 	 * and 63 will always be returned as 0.
3127 	 */
3128 	return lower_32_bits(elf_hwcap);
3129 }
3130 
3131 unsigned long cpu_get_elf_hwcap2(void)
3132 {
3133 	return upper_32_bits(elf_hwcap);
3134 }
3135 
3136 static void __init setup_system_capabilities(void)
3137 {
3138 	/*
3139 	 * We have finalised the system-wide safe feature
3140 	 * registers, finalise the capabilities that depend
3141 	 * on it. Also enable all the available capabilities,
3142 	 * that are not enabled already.
3143 	 */
3144 	update_cpu_capabilities(SCOPE_SYSTEM);
3145 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3146 }
3147 
3148 void __init setup_cpu_features(void)
3149 {
3150 	u32 cwg;
3151 
3152 	setup_system_capabilities();
3153 	setup_elf_hwcaps(arm64_elf_hwcaps);
3154 
3155 	if (system_supports_32bit_el0())
3156 		setup_elf_hwcaps(compat_elf_hwcaps);
3157 
3158 	if (system_uses_ttbr0_pan())
3159 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
3160 
3161 	sve_setup();
3162 	sme_setup();
3163 	minsigstksz_setup();
3164 
3165 	/* Advertise that we have computed the system capabilities */
3166 	finalize_system_capabilities();
3167 
3168 	/*
3169 	 * Check for sane CTR_EL0.CWG value.
3170 	 */
3171 	cwg = cache_type_cwg();
3172 	if (!cwg)
3173 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
3174 			ARCH_DMA_MINALIGN);
3175 }
3176 
3177 static int enable_mismatched_32bit_el0(unsigned int cpu)
3178 {
3179 	/*
3180 	 * The first 32-bit-capable CPU we detected and so can no longer
3181 	 * be offlined by userspace. -1 indicates we haven't yet onlined
3182 	 * a 32-bit-capable CPU.
3183 	 */
3184 	static int lucky_winner = -1;
3185 
3186 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
3187 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
3188 
3189 	if (cpu_32bit) {
3190 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
3191 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
3192 	}
3193 
3194 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
3195 		return 0;
3196 
3197 	if (lucky_winner >= 0)
3198 		return 0;
3199 
3200 	/*
3201 	 * We've detected a mismatch. We need to keep one of our CPUs with
3202 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
3203 	 * every CPU in the system for a 32-bit task.
3204 	 */
3205 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
3206 							 cpu_active_mask);
3207 	get_cpu_device(lucky_winner)->offline_disabled = true;
3208 	setup_elf_hwcaps(compat_elf_hwcaps);
3209 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
3210 		cpu, lucky_winner);
3211 	return 0;
3212 }
3213 
3214 static int __init init_32bit_el0_mask(void)
3215 {
3216 	if (!allow_mismatched_32bit_el0)
3217 		return 0;
3218 
3219 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3220 		return -ENOMEM;
3221 
3222 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3223 				 "arm64/mismatched_32bit_el0:online",
3224 				 enable_mismatched_32bit_el0, NULL);
3225 }
3226 subsys_initcall_sync(init_32bit_el0_mask);
3227 
3228 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3229 {
3230 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
3231 }
3232 
3233 /*
3234  * We emulate only the following system register space.
3235  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
3236  * See Table C5-6 System instruction encodings for System register accesses,
3237  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3238  */
3239 static inline bool __attribute_const__ is_emulated(u32 id)
3240 {
3241 	return (sys_reg_Op0(id) == 0x3 &&
3242 		sys_reg_CRn(id) == 0x0 &&
3243 		sys_reg_Op1(id) == 0x0 &&
3244 		(sys_reg_CRm(id) == 0 ||
3245 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
3246 }
3247 
3248 /*
3249  * With CRm == 0, reg should be one of :
3250  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3251  */
3252 static inline int emulate_id_reg(u32 id, u64 *valp)
3253 {
3254 	switch (id) {
3255 	case SYS_MIDR_EL1:
3256 		*valp = read_cpuid_id();
3257 		break;
3258 	case SYS_MPIDR_EL1:
3259 		*valp = SYS_MPIDR_SAFE_VAL;
3260 		break;
3261 	case SYS_REVIDR_EL1:
3262 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3263 		*valp = 0;
3264 		break;
3265 	default:
3266 		return -EINVAL;
3267 	}
3268 
3269 	return 0;
3270 }
3271 
3272 static int emulate_sys_reg(u32 id, u64 *valp)
3273 {
3274 	struct arm64_ftr_reg *regp;
3275 
3276 	if (!is_emulated(id))
3277 		return -EINVAL;
3278 
3279 	if (sys_reg_CRm(id) == 0)
3280 		return emulate_id_reg(id, valp);
3281 
3282 	regp = get_arm64_ftr_reg_nowarn(id);
3283 	if (regp)
3284 		*valp = arm64_ftr_reg_user_value(regp);
3285 	else
3286 		/*
3287 		 * The untracked registers are either IMPLEMENTATION DEFINED
3288 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3289 		 */
3290 		*valp = 0;
3291 	return 0;
3292 }
3293 
3294 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3295 {
3296 	int rc;
3297 	u64 val;
3298 
3299 	rc = emulate_sys_reg(sys_reg, &val);
3300 	if (!rc) {
3301 		pt_regs_write_reg(regs, rt, val);
3302 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3303 	}
3304 	return rc;
3305 }
3306 
3307 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3308 {
3309 	u32 sys_reg, rt;
3310 
3311 	/*
3312 	 * sys_reg values are defined as used in mrs/msr instruction.
3313 	 * shift the imm value to get the encoding.
3314 	 */
3315 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3316 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3317 	return do_emulate_mrs(regs, sys_reg, rt);
3318 }
3319 
3320 static struct undef_hook mrs_hook = {
3321 	.instr_mask = 0xffff0000,
3322 	.instr_val  = 0xd5380000,
3323 	.pstate_mask = PSR_AA32_MODE_MASK,
3324 	.pstate_val = PSR_MODE_EL0t,
3325 	.fn = emulate_mrs,
3326 };
3327 
3328 static int __init enable_mrs_emulation(void)
3329 {
3330 	register_undef_hook(&mrs_hook);
3331 	return 0;
3332 }
3333 
3334 core_initcall(enable_mrs_emulation);
3335 
3336 enum mitigation_state arm64_get_meltdown_state(void)
3337 {
3338 	if (__meltdown_safe)
3339 		return SPECTRE_UNAFFECTED;
3340 
3341 	if (arm64_kernel_unmapped_at_el0())
3342 		return SPECTRE_MITIGATED;
3343 
3344 	return SPECTRE_VULNERABLE;
3345 }
3346 
3347 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3348 			  char *buf)
3349 {
3350 	switch (arm64_get_meltdown_state()) {
3351 	case SPECTRE_UNAFFECTED:
3352 		return sprintf(buf, "Not affected\n");
3353 
3354 	case SPECTRE_MITIGATED:
3355 		return sprintf(buf, "Mitigation: PTI\n");
3356 
3357 	default:
3358 		return sprintf(buf, "Vulnerable\n");
3359 	}
3360 }
3361