xref: /linux/arch/arm64/kernel/cpufeature.c (revision e7b2b108cdeab76a7e7324459e50b0c1214c0386)
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/kstrtox.h>
69 #include <linux/sort.h>
70 #include <linux/stop_machine.h>
71 #include <linux/sysfs.h>
72 #include <linux/types.h>
73 #include <linux/minmax.h>
74 #include <linux/mm.h>
75 #include <linux/cpu.h>
76 #include <linux/kasan.h>
77 #include <linux/percpu.h>
78 
79 #include <asm/cpu.h>
80 #include <asm/cpufeature.h>
81 #include <asm/cpu_ops.h>
82 #include <asm/fpsimd.h>
83 #include <asm/hwcap.h>
84 #include <asm/insn.h>
85 #include <asm/kvm_host.h>
86 #include <asm/mmu_context.h>
87 #include <asm/mte.h>
88 #include <asm/processor.h>
89 #include <asm/smp.h>
90 #include <asm/sysreg.h>
91 #include <asm/traps.h>
92 #include <asm/vectors.h>
93 #include <asm/virt.h>
94 
95 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
96 static DECLARE_BITMAP(elf_hwcap, MAX_CPU_FEATURES) __read_mostly;
97 
98 #ifdef CONFIG_COMPAT
99 #define COMPAT_ELF_HWCAP_DEFAULT	\
100 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
101 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
102 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
103 				 COMPAT_HWCAP_LPAE)
104 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
105 unsigned int compat_elf_hwcap2 __read_mostly;
106 #endif
107 
108 DECLARE_BITMAP(system_cpucaps, ARM64_NCAPS);
109 EXPORT_SYMBOL(system_cpucaps);
110 static struct arm64_cpu_capabilities const __ro_after_init *cpucap_ptrs[ARM64_NCAPS];
111 
112 DECLARE_BITMAP(boot_cpucaps, ARM64_NCAPS);
113 
114 bool arm64_use_ng_mappings = false;
115 EXPORT_SYMBOL(arm64_use_ng_mappings);
116 
117 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
118 
119 /*
120  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
121  * support it?
122  */
123 static bool __read_mostly allow_mismatched_32bit_el0;
124 
125 /*
126  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
127  * seen at least one CPU capable of 32-bit EL0.
128  */
129 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
130 
131 /*
132  * Mask of CPUs supporting 32-bit EL0.
133  * Only valid if arm64_mismatched_32bit_el0 is enabled.
134  */
135 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
136 
137 void dump_cpu_features(void)
138 {
139 	/* file-wide pr_fmt adds "CPU features: " prefix */
140 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &system_cpucaps);
141 }
142 
143 #define ARM64_CPUID_FIELDS(reg, field, min_value)			\
144 		.sys_reg = SYS_##reg,							\
145 		.field_pos = reg##_##field##_SHIFT,						\
146 		.field_width = reg##_##field##_WIDTH,						\
147 		.sign = reg##_##field##_SIGNED,							\
148 		.min_field_value = reg##_##field##_##min_value,
149 
150 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
151 	{						\
152 		.sign = SIGNED,				\
153 		.visible = VISIBLE,			\
154 		.strict = STRICT,			\
155 		.type = TYPE,				\
156 		.shift = SHIFT,				\
157 		.width = WIDTH,				\
158 		.safe_val = SAFE_VAL,			\
159 	}
160 
161 /* Define a feature with unsigned values */
162 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
163 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
164 
165 /* Define a feature with a signed value */
166 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
167 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
168 
169 #define ARM64_FTR_END					\
170 	{						\
171 		.width = 0,				\
172 	}
173 
174 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
175 
176 static bool __system_matches_cap(unsigned int n);
177 
178 /*
179  * NOTE: Any changes to the visibility of features should be kept in
180  * sync with the documentation of the CPU feature register ABI.
181  */
182 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
183 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_RNDR_SHIFT, 4, 0),
184 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_TLB_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_TS_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_FHM_SHIFT, 4, 0),
187 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_DP_SHIFT, 4, 0),
188 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SM4_SHIFT, 4, 0),
189 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SM3_SHIFT, 4, 0),
190 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA3_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_RDM_SHIFT, 4, 0),
192 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_ATOMIC_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_CRC32_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA2_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_SHA1_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_EL1_AES_SHIFT, 4, 0),
197 	ARM64_FTR_END,
198 };
199 
200 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_I8MM_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_DGH_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_BF16_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_SPECRES_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_SB_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_FRINTTS_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
208 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_GPI_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
210 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_GPA_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_LRCPC_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_FCMA_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_JSCVT_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
215 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_EL1_API_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
217 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_EL1_APA_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_EL1_DPB_SHIFT, 4, 0),
219 	ARM64_FTR_END,
220 };
221 
222 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
223 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_CSSC_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_RPRFM_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_CLRBHB_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_BC_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_MOPS_SHIFT, 4, 0),
228 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
229 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR2_EL1_APA3_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
231 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_GPA3_SHIFT, 4, 0),
232 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_RPRES_SHIFT, 4, 0),
233 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_WFxT_SHIFT, 4, 0),
234 	ARM64_FTR_END,
235 };
236 
237 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
238 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV3_SHIFT, 4, 0),
239 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV2_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_DIT_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_AMU_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_MPAM_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SEL2_SHIFT, 4, 0),
244 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
245 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SVE_SHIFT, 4, 0),
246 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_RAS_SHIFT, 4, 0),
247 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_GIC_SHIFT, 4, 0),
248 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_AdvSIMD_SHIFT, 4, ID_AA64PFR0_EL1_AdvSIMD_NI),
249 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_FP_SHIFT, 4, ID_AA64PFR0_EL1_FP_NI),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL3_SHIFT, 4, 0),
251 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL2_SHIFT, 4, 0),
252 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL1_SHIFT, 4, ID_AA64PFR0_EL1_ELx_64BIT_ONLY),
253 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL0_SHIFT, 4, ID_AA64PFR0_EL1_ELx_64BIT_ONLY),
254 	ARM64_FTR_END,
255 };
256 
257 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
258 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
259 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_SME_SHIFT, 4, 0),
260 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_MPAM_frac_SHIFT, 4, 0),
261 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_RAS_frac_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
263 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_MTE_SHIFT, 4, ID_AA64PFR1_EL1_MTE_NI),
264 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_SSBS_SHIFT, 4, ID_AA64PFR1_EL1_SSBS_NI),
265 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
266 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_BT_SHIFT, 4, 0),
267 	ARM64_FTR_END,
268 };
269 
270 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
271 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
272 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_F64MM_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_F32MM_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_I8MM_SHIFT, 4, 0),
277 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
278 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SM4_SHIFT, 4, 0),
279 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
280 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SHA3_SHIFT, 4, 0),
281 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
282 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_B16B16_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
284 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_BF16_SHIFT, 4, 0),
285 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
286 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_BitPerm_SHIFT, 4, 0),
287 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
288 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_AES_SHIFT, 4, 0),
289 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
290 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SVEver_SHIFT, 4, 0),
291 	ARM64_FTR_END,
292 };
293 
294 static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
295 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
296 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_FA64_SHIFT, 1, 0),
297 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
298 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SMEver_SHIFT, 4, 0),
299 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
300 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I64_SHIFT, 4, 0),
301 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
302 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, 0),
303 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
304 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I32_SHIFT, 4, 0),
305 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
306 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16B16_SHIFT, 1, 0),
307 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
308 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F16_SHIFT, 1, 0),
309 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
310 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I8I32_SHIFT, 4, 0),
311 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
312 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F32_SHIFT, 1, 0),
313 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
314 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16F32_SHIFT, 1, 0),
315 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
316 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_BI32I32_SHIFT, 1, 0),
317 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
318 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F32F32_SHIFT, 1, 0),
319 	ARM64_FTR_END,
320 };
321 
322 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
323 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_ECV_SHIFT, 4, 0),
324 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_FGT_SHIFT, 4, 0),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_EXS_SHIFT, 4, 0),
326 	/*
327 	 * Page size not being supported at Stage-2 is not fatal. You
328 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
329 	 * your favourite nesting hypervisor.
330 	 *
331 	 * There is a small corner case where the hypervisor explicitly
332 	 * advertises a given granule size at Stage-2 (value 2) on some
333 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
334 	 * vCPUs. Although this is not forbidden by the architecture, it
335 	 * indicates that the hypervisor is being silly (or buggy).
336 	 *
337 	 * We make no effort to cope with this and pretend that if these
338 	 * fields are inconsistent across vCPUs, then it isn't worth
339 	 * trying to bring KVM up.
340 	 */
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN4_2_SHIFT, 4, 1),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN64_2_SHIFT, 4, 1),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN16_2_SHIFT, 4, 1),
344 	/*
345 	 * We already refuse to boot CPUs that don't support our configured
346 	 * page size, so we can only detect mismatches for a page size other
347 	 * than the one we're currently using. Unfortunately, SoCs like this
348 	 * exist in the wild so, even though we don't like it, we'll have to go
349 	 * along with it and treat them as non-strict.
350 	 */
351 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN4_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN4_NI),
352 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN64_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN64_NI),
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN16_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN16_NI),
354 
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_BIGENDEL0_SHIFT, 4, 0),
356 	/* Linux shouldn't care about secure memory */
357 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_SNSMEM_SHIFT, 4, 0),
358 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_BIGEND_SHIFT, 4, 0),
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_ASIDBITS_SHIFT, 4, 0),
360 	/*
361 	 * Differing PARange is fine as long as all peripherals and memory are mapped
362 	 * within the minimum PARange of all CPUs
363 	 */
364 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_PARANGE_SHIFT, 4, 0),
365 	ARM64_FTR_END,
366 };
367 
368 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
369 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_TIDCP1_SHIFT, 4, 0),
370 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_AFP_SHIFT, 4, 0),
371 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_HCX_SHIFT, 4, 0),
372 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_ETS_SHIFT, 4, 0),
373 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_TWED_SHIFT, 4, 0),
374 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_XNX_SHIFT, 4, 0),
375 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_EL1_SpecSEI_SHIFT, 4, 0),
376 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_PAN_SHIFT, 4, 0),
377 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_LO_SHIFT, 4, 0),
378 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_HPDS_SHIFT, 4, 0),
379 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_VH_SHIFT, 4, 0),
380 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_VMIDBits_SHIFT, 4, 0),
381 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_HAFDBS_SHIFT, 4, 0),
382 	ARM64_FTR_END,
383 };
384 
385 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_E0PD_SHIFT, 4, 0),
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_EVT_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_BBM_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_TTL_SHIFT, 4, 0),
390 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_FWB_SHIFT, 4, 0),
391 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_IDS_SHIFT, 4, 0),
392 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_AT_SHIFT, 4, 0),
393 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_ST_SHIFT, 4, 0),
394 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_NV_SHIFT, 4, 0),
395 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_CCIDX_SHIFT, 4, 0),
396 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_VARange_SHIFT, 4, 0),
397 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_IESB_SHIFT, 4, 0),
398 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_LSM_SHIFT, 4, 0),
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_UAO_SHIFT, 4, 0),
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_CnP_SHIFT, 4, 0),
401 	ARM64_FTR_END,
402 };
403 
404 static const struct arm64_ftr_bits ftr_id_aa64mmfr3[] = {
405 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_S1PIE_SHIFT, 4, 0),
406 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_TCRX_SHIFT, 4, 0),
407 	ARM64_FTR_END,
408 };
409 
410 static const struct arm64_ftr_bits ftr_ctr[] = {
411 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
412 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_DIC_SHIFT, 1, 1),
413 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_IDC_SHIFT, 1, 1),
414 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_EL0_CWG_SHIFT, 4, 0),
415 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_EL0_ERG_SHIFT, 4, 0),
416 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_DminLine_SHIFT, 4, 1),
417 	/*
418 	 * Linux can handle differing I-cache policies. Userspace JITs will
419 	 * make use of *minLine.
420 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
421 	 */
422 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_EL0_L1Ip_SHIFT, 2, CTR_EL0_L1Ip_VIPT),	/* L1Ip */
423 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_IminLine_SHIFT, 4, 0),
424 	ARM64_FTR_END,
425 };
426 
427 static struct arm64_ftr_override __ro_after_init no_override = { };
428 
429 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
430 	.name		= "SYS_CTR_EL0",
431 	.ftr_bits	= ftr_ctr,
432 	.override	= &no_override,
433 };
434 
435 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
436 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_InnerShr_SHIFT, 4, 0xf),
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_FCSE_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_AuxReg_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_TCM_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_ShareLvl_SHIFT, 4, 0),
441 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_OuterShr_SHIFT, 4, 0xf),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_PMSA_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_VMSA_SHIFT, 4, 0),
444 	ARM64_FTR_END,
445 };
446 
447 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
448 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_DoubleLock_SHIFT, 4, 0),
449 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_PMSVer_SHIFT, 4, 0),
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_CTX_CMPs_SHIFT, 4, 0),
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_WRPs_SHIFT, 4, 0),
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_BRPs_SHIFT, 4, 0),
453 	/*
454 	 * We can instantiate multiple PMU instances with different levels
455 	 * of support.
456 	 */
457 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_EL1_PMUVer_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_EL1_DebugVer_SHIFT, 4, 0x6),
459 	ARM64_FTR_END,
460 };
461 
462 static const struct arm64_ftr_bits ftr_mvfr0[] = {
463 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPRound_SHIFT, 4, 0),
464 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPShVec_SHIFT, 4, 0),
465 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPSqrt_SHIFT, 4, 0),
466 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPDivide_SHIFT, 4, 0),
467 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPTrap_SHIFT, 4, 0),
468 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPDP_SHIFT, 4, 0),
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPSP_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_SIMDReg_SHIFT, 4, 0),
471 	ARM64_FTR_END,
472 };
473 
474 static const struct arm64_ftr_bits ftr_mvfr1[] = {
475 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDFMAC_SHIFT, 4, 0),
476 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPHP_SHIFT, 4, 0),
477 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDHP_SHIFT, 4, 0),
478 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDSP_SHIFT, 4, 0),
479 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDInt_SHIFT, 4, 0),
480 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDLS_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPDNaN_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPFtZ_SHIFT, 4, 0),
483 	ARM64_FTR_END,
484 };
485 
486 static const struct arm64_ftr_bits ftr_mvfr2[] = {
487 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_EL1_FPMisc_SHIFT, 4, 0),
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_EL1_SIMDMisc_SHIFT, 4, 0),
489 	ARM64_FTR_END,
490 };
491 
492 static const struct arm64_ftr_bits ftr_dczid[] = {
493 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_EL0_DZP_SHIFT, 1, 1),
494 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_EL0_BS_SHIFT, 4, 0),
495 	ARM64_FTR_END,
496 };
497 
498 static const struct arm64_ftr_bits ftr_gmid[] = {
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, GMID_EL1_BS_SHIFT, 4, 0),
500 	ARM64_FTR_END,
501 };
502 
503 static const struct arm64_ftr_bits ftr_id_isar0[] = {
504 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Divide_SHIFT, 4, 0),
505 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Debug_SHIFT, 4, 0),
506 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Coproc_SHIFT, 4, 0),
507 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_CmpBranch_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_BitField_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_BitCount_SHIFT, 4, 0),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Swap_SHIFT, 4, 0),
511 	ARM64_FTR_END,
512 };
513 
514 static const struct arm64_ftr_bits ftr_id_isar5[] = {
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_RDM_SHIFT, 4, 0),
516 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_CRC32_SHIFT, 4, 0),
517 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SHA2_SHIFT, 4, 0),
518 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SHA1_SHIFT, 4, 0),
519 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_AES_SHIFT, 4, 0),
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SEVL_SHIFT, 4, 0),
521 	ARM64_FTR_END,
522 };
523 
524 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
525 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_EVT_SHIFT, 4, 0),
526 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_CCIDX_SHIFT, 4, 0),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_LSM_SHIFT, 4, 0),
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_HPDS_SHIFT, 4, 0),
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_CnP_SHIFT, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_XNX_SHIFT, 4, 0),
531 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_AC2_SHIFT, 4, 0),
532 
533 	/*
534 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
535 	 * external abort on speculative read. It is safe to assume that an
536 	 * SError might be generated than it will not be. Hence it has been
537 	 * classified as FTR_HIGHER_SAFE.
538 	 */
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_EL1_SpecSEI_SHIFT, 4, 0),
540 	ARM64_FTR_END,
541 };
542 
543 static const struct arm64_ftr_bits ftr_id_isar4[] = {
544 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SWP_frac_SHIFT, 4, 0),
545 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_PSR_M_SHIFT, 4, 0),
546 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SynchPrim_frac_SHIFT, 4, 0),
547 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Barrier_SHIFT, 4, 0),
548 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SMC_SHIFT, 4, 0),
549 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Writeback_SHIFT, 4, 0),
550 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_WithShifts_SHIFT, 4, 0),
551 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Unpriv_SHIFT, 4, 0),
552 	ARM64_FTR_END,
553 };
554 
555 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
556 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_EL1_ETS_SHIFT, 4, 0),
557 	ARM64_FTR_END,
558 };
559 
560 static const struct arm64_ftr_bits ftr_id_isar6[] = {
561 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_I8MM_SHIFT, 4, 0),
562 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_BF16_SHIFT, 4, 0),
563 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_SPECRES_SHIFT, 4, 0),
564 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_SB_SHIFT, 4, 0),
565 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_FHM_SHIFT, 4, 0),
566 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_DP_SHIFT, 4, 0),
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_JSCVT_SHIFT, 4, 0),
568 	ARM64_FTR_END,
569 };
570 
571 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
572 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_DIT_SHIFT, 4, 0),
573 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_CSV2_SHIFT, 4, 0),
574 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State3_SHIFT, 4, 0),
575 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State2_SHIFT, 4, 0),
576 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State1_SHIFT, 4, 0),
577 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State0_SHIFT, 4, 0),
578 	ARM64_FTR_END,
579 };
580 
581 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
582 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_GIC_SHIFT, 4, 0),
583 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Virt_frac_SHIFT, 4, 0),
584 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Sec_frac_SHIFT, 4, 0),
585 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_GenTimer_SHIFT, 4, 0),
586 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Virtualization_SHIFT, 4, 0),
587 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_MProgMod_SHIFT, 4, 0),
588 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Security_SHIFT, 4, 0),
589 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_ProgMod_SHIFT, 4, 0),
590 	ARM64_FTR_END,
591 };
592 
593 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
594 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_EL1_SSBS_SHIFT, 4, 0),
595 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_EL1_CSV3_SHIFT, 4, 0),
596 	ARM64_FTR_END,
597 };
598 
599 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
600 	/* [31:28] TraceFilt */
601 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_DFR0_EL1_PerfMon_SHIFT, 4, 0),
602 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MProfDbg_SHIFT, 4, 0),
603 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MMapTrc_SHIFT, 4, 0),
604 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopTrc_SHIFT, 4, 0),
605 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MMapDbg_SHIFT, 4, 0),
606 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopSDbg_SHIFT, 4, 0),
607 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopDbg_SHIFT, 4, 0),
608 	ARM64_FTR_END,
609 };
610 
611 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
612 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_EL1_MTPMU_SHIFT, 4, 0),
613 	ARM64_FTR_END,
614 };
615 
616 /*
617  * Common ftr bits for a 32bit register with all hidden, strict
618  * attributes, with 4bit feature fields and a default safe value of
619  * 0. Covers the following 32bit registers:
620  * id_isar[1-3], id_mmfr[1-3]
621  */
622 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
623 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
624 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
625 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
626 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
627 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
628 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
629 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
630 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
631 	ARM64_FTR_END,
632 };
633 
634 /* Table for a single 32bit feature value */
635 static const struct arm64_ftr_bits ftr_single32[] = {
636 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
637 	ARM64_FTR_END,
638 };
639 
640 static const struct arm64_ftr_bits ftr_raz[] = {
641 	ARM64_FTR_END,
642 };
643 
644 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
645 		.sys_id = id,					\
646 		.reg = 	&(struct arm64_ftr_reg){		\
647 			.name = id_str,				\
648 			.override = (ovr),			\
649 			.ftr_bits = &((table)[0]),		\
650 	}}
651 
652 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
653 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
654 
655 #define ARM64_FTR_REG(id, table)		\
656 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
657 
658 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
659 struct arm64_ftr_override __ro_after_init id_aa64pfr0_override;
660 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
661 struct arm64_ftr_override __ro_after_init id_aa64zfr0_override;
662 struct arm64_ftr_override __ro_after_init id_aa64smfr0_override;
663 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
664 struct arm64_ftr_override __ro_after_init id_aa64isar2_override;
665 
666 struct arm64_ftr_override arm64_sw_feature_override;
667 
668 static const struct __ftr_reg_entry {
669 	u32			sys_id;
670 	struct arm64_ftr_reg 	*reg;
671 } arm64_ftr_regs[] = {
672 
673 	/* Op1 = 0, CRn = 0, CRm = 1 */
674 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
675 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
676 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
677 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
678 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
679 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
680 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
681 
682 	/* Op1 = 0, CRn = 0, CRm = 2 */
683 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
684 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
685 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
686 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
687 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
688 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
689 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
690 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
691 
692 	/* Op1 = 0, CRn = 0, CRm = 3 */
693 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_mvfr0),
694 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_mvfr1),
695 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
696 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
697 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
698 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
699 
700 	/* Op1 = 0, CRn = 0, CRm = 4 */
701 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0,
702 			       &id_aa64pfr0_override),
703 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
704 			       &id_aa64pfr1_override),
705 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0,
706 			       &id_aa64zfr0_override),
707 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64SMFR0_EL1, ftr_id_aa64smfr0,
708 			       &id_aa64smfr0_override),
709 
710 	/* Op1 = 0, CRn = 0, CRm = 5 */
711 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
712 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
713 
714 	/* Op1 = 0, CRn = 0, CRm = 6 */
715 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
716 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
717 			       &id_aa64isar1_override),
718 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2,
719 			       &id_aa64isar2_override),
720 
721 	/* Op1 = 0, CRn = 0, CRm = 7 */
722 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
723 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
724 			       &id_aa64mmfr1_override),
725 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
726 	ARM64_FTR_REG(SYS_ID_AA64MMFR3_EL1, ftr_id_aa64mmfr3),
727 
728 	/* Op1 = 1, CRn = 0, CRm = 0 */
729 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
730 
731 	/* Op1 = 3, CRn = 0, CRm = 0 */
732 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
733 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
734 
735 	/* Op1 = 3, CRn = 14, CRm = 0 */
736 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
737 };
738 
739 static int search_cmp_ftr_reg(const void *id, const void *regp)
740 {
741 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
742 }
743 
744 /*
745  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
746  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
747  * ascending order of sys_id, we use binary search to find a matching
748  * entry.
749  *
750  * returns - Upon success,  matching ftr_reg entry for id.
751  *         - NULL on failure. It is upto the caller to decide
752  *	     the impact of a failure.
753  */
754 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
755 {
756 	const struct __ftr_reg_entry *ret;
757 
758 	ret = bsearch((const void *)(unsigned long)sys_id,
759 			arm64_ftr_regs,
760 			ARRAY_SIZE(arm64_ftr_regs),
761 			sizeof(arm64_ftr_regs[0]),
762 			search_cmp_ftr_reg);
763 	if (ret)
764 		return ret->reg;
765 	return NULL;
766 }
767 
768 /*
769  * get_arm64_ftr_reg - Looks up a feature register entry using
770  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
771  *
772  * returns - Upon success,  matching ftr_reg entry for id.
773  *         - NULL on failure but with an WARN_ON().
774  */
775 struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
776 {
777 	struct arm64_ftr_reg *reg;
778 
779 	reg = get_arm64_ftr_reg_nowarn(sys_id);
780 
781 	/*
782 	 * Requesting a non-existent register search is an error. Warn
783 	 * and let the caller handle it.
784 	 */
785 	WARN_ON(!reg);
786 	return reg;
787 }
788 
789 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
790 			       s64 ftr_val)
791 {
792 	u64 mask = arm64_ftr_mask(ftrp);
793 
794 	reg &= ~mask;
795 	reg |= (ftr_val << ftrp->shift) & mask;
796 	return reg;
797 }
798 
799 s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
800 				s64 cur)
801 {
802 	s64 ret = 0;
803 
804 	switch (ftrp->type) {
805 	case FTR_EXACT:
806 		ret = ftrp->safe_val;
807 		break;
808 	case FTR_LOWER_SAFE:
809 		ret = min(new, cur);
810 		break;
811 	case FTR_HIGHER_OR_ZERO_SAFE:
812 		if (!cur || !new)
813 			break;
814 		fallthrough;
815 	case FTR_HIGHER_SAFE:
816 		ret = max(new, cur);
817 		break;
818 	default:
819 		BUG();
820 	}
821 
822 	return ret;
823 }
824 
825 static void __init sort_ftr_regs(void)
826 {
827 	unsigned int i;
828 
829 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
830 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
831 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
832 		unsigned int j = 0;
833 
834 		/*
835 		 * Features here must be sorted in descending order with respect
836 		 * to their shift values and should not overlap with each other.
837 		 */
838 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
839 			unsigned int width = ftr_reg->ftr_bits[j].width;
840 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
841 			unsigned int prev_shift;
842 
843 			WARN((shift  + width) > 64,
844 				"%s has invalid feature at shift %d\n",
845 				ftr_reg->name, shift);
846 
847 			/*
848 			 * Skip the first feature. There is nothing to
849 			 * compare against for now.
850 			 */
851 			if (j == 0)
852 				continue;
853 
854 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
855 			WARN((shift + width) > prev_shift,
856 				"%s has feature overlap at shift %d\n",
857 				ftr_reg->name, shift);
858 		}
859 
860 		/*
861 		 * Skip the first register. There is nothing to
862 		 * compare against for now.
863 		 */
864 		if (i == 0)
865 			continue;
866 		/*
867 		 * Registers here must be sorted in ascending order with respect
868 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
869 		 * to work correctly.
870 		 */
871 		BUG_ON(arm64_ftr_regs[i].sys_id <= arm64_ftr_regs[i - 1].sys_id);
872 	}
873 }
874 
875 /*
876  * Initialise the CPU feature register from Boot CPU values.
877  * Also initiliases the strict_mask for the register.
878  * Any bits that are not covered by an arm64_ftr_bits entry are considered
879  * RES0 for the system-wide value, and must strictly match.
880  */
881 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
882 {
883 	u64 val = 0;
884 	u64 strict_mask = ~0x0ULL;
885 	u64 user_mask = 0;
886 	u64 valid_mask = 0;
887 
888 	const struct arm64_ftr_bits *ftrp;
889 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
890 
891 	if (!reg)
892 		return;
893 
894 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
895 		u64 ftr_mask = arm64_ftr_mask(ftrp);
896 		s64 ftr_new = arm64_ftr_value(ftrp, new);
897 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
898 
899 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
900 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
901 			char *str = NULL;
902 
903 			if (ftr_ovr != tmp) {
904 				/* Unsafe, remove the override */
905 				reg->override->mask &= ~ftr_mask;
906 				reg->override->val &= ~ftr_mask;
907 				tmp = ftr_ovr;
908 				str = "ignoring override";
909 			} else if (ftr_new != tmp) {
910 				/* Override was valid */
911 				ftr_new = tmp;
912 				str = "forced";
913 			} else if (ftr_ovr == tmp) {
914 				/* Override was the safe value */
915 				str = "already set";
916 			}
917 
918 			if (str)
919 				pr_warn("%s[%d:%d]: %s to %llx\n",
920 					reg->name,
921 					ftrp->shift + ftrp->width - 1,
922 					ftrp->shift, str, tmp);
923 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
924 			reg->override->val &= ~ftr_mask;
925 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
926 				reg->name,
927 				ftrp->shift + ftrp->width - 1,
928 				ftrp->shift);
929 		}
930 
931 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
932 
933 		valid_mask |= ftr_mask;
934 		if (!ftrp->strict)
935 			strict_mask &= ~ftr_mask;
936 		if (ftrp->visible)
937 			user_mask |= ftr_mask;
938 		else
939 			reg->user_val = arm64_ftr_set_value(ftrp,
940 							    reg->user_val,
941 							    ftrp->safe_val);
942 	}
943 
944 	val &= valid_mask;
945 
946 	reg->sys_val = val;
947 	reg->strict_mask = strict_mask;
948 	reg->user_mask = user_mask;
949 }
950 
951 extern const struct arm64_cpu_capabilities arm64_errata[];
952 static const struct arm64_cpu_capabilities arm64_features[];
953 
954 static void __init
955 init_cpucap_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
956 {
957 	for (; caps->matches; caps++) {
958 		if (WARN(caps->capability >= ARM64_NCAPS,
959 			"Invalid capability %d\n", caps->capability))
960 			continue;
961 		if (WARN(cpucap_ptrs[caps->capability],
962 			"Duplicate entry for capability %d\n",
963 			caps->capability))
964 			continue;
965 		cpucap_ptrs[caps->capability] = caps;
966 	}
967 }
968 
969 static void __init init_cpucap_indirect_list(void)
970 {
971 	init_cpucap_indirect_list_from_array(arm64_features);
972 	init_cpucap_indirect_list_from_array(arm64_errata);
973 }
974 
975 static void __init setup_boot_cpu_capabilities(void);
976 
977 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
978 {
979 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
980 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
981 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
982 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
983 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
984 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
985 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
986 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
987 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
988 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
989 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
990 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
991 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
992 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
993 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
994 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
995 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
996 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
997 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
998 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
999 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
1000 }
1001 
1002 #ifdef CONFIG_ARM64_PSEUDO_NMI
1003 static bool enable_pseudo_nmi;
1004 
1005 static int __init early_enable_pseudo_nmi(char *p)
1006 {
1007 	return kstrtobool(p, &enable_pseudo_nmi);
1008 }
1009 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1010 
1011 static __init void detect_system_supports_pseudo_nmi(void)
1012 {
1013 	struct device_node *np;
1014 
1015 	if (!enable_pseudo_nmi)
1016 		return;
1017 
1018 	/*
1019 	 * Detect broken MediaTek firmware that doesn't properly save and
1020 	 * restore GIC priorities.
1021 	 */
1022 	np = of_find_compatible_node(NULL, NULL, "arm,gic-v3");
1023 	if (np && of_property_read_bool(np, "mediatek,broken-save-restore-fw")) {
1024 		pr_info("Pseudo-NMI disabled due to MediaTek Chromebook GICR save problem\n");
1025 		enable_pseudo_nmi = false;
1026 	}
1027 	of_node_put(np);
1028 }
1029 #else /* CONFIG_ARM64_PSEUDO_NMI */
1030 static inline void detect_system_supports_pseudo_nmi(void) { }
1031 #endif
1032 
1033 void __init init_cpu_features(struct cpuinfo_arm64 *info)
1034 {
1035 	/* Before we start using the tables, make sure it is sorted */
1036 	sort_ftr_regs();
1037 
1038 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
1039 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
1040 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
1041 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
1042 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
1043 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
1044 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
1045 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
1046 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
1047 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
1048 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
1049 	init_cpu_ftr_reg(SYS_ID_AA64MMFR3_EL1, info->reg_id_aa64mmfr3);
1050 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
1051 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
1052 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
1053 	init_cpu_ftr_reg(SYS_ID_AA64SMFR0_EL1, info->reg_id_aa64smfr0);
1054 
1055 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
1056 		init_32bit_cpu_features(&info->aarch32);
1057 
1058 	if (IS_ENABLED(CONFIG_ARM64_SVE) &&
1059 	    id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1))) {
1060 		unsigned long cpacr = cpacr_save_enable_kernel_sve();
1061 
1062 		vec_init_vq_map(ARM64_VEC_SVE);
1063 
1064 		cpacr_restore(cpacr);
1065 	}
1066 
1067 	if (IS_ENABLED(CONFIG_ARM64_SME) &&
1068 	    id_aa64pfr1_sme(read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1))) {
1069 		unsigned long cpacr = cpacr_save_enable_kernel_sme();
1070 
1071 		/*
1072 		 * We mask out SMPS since even if the hardware
1073 		 * supports priorities the kernel does not at present
1074 		 * and we block access to them.
1075 		 */
1076 		info->reg_smidr = read_cpuid(SMIDR_EL1) & ~SMIDR_EL1_SMPS;
1077 		vec_init_vq_map(ARM64_VEC_SME);
1078 
1079 		cpacr_restore(cpacr);
1080 	}
1081 
1082 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
1083 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
1084 
1085 	/*
1086 	 * Initialize the indirect array of CPU capabilities pointers before we
1087 	 * handle the boot CPU below.
1088 	 */
1089 	init_cpucap_indirect_list();
1090 
1091 	/*
1092 	 * Detect broken pseudo-NMI. Must be called _before_ the call to
1093 	 * setup_boot_cpu_capabilities() since it interacts with
1094 	 * can_use_gic_priorities().
1095 	 */
1096 	detect_system_supports_pseudo_nmi();
1097 
1098 	/*
1099 	 * Detect and enable early CPU capabilities based on the boot CPU,
1100 	 * after we have initialised the CPU feature infrastructure.
1101 	 */
1102 	setup_boot_cpu_capabilities();
1103 }
1104 
1105 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
1106 {
1107 	const struct arm64_ftr_bits *ftrp;
1108 
1109 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
1110 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
1111 		s64 ftr_new = arm64_ftr_value(ftrp, new);
1112 
1113 		if (ftr_cur == ftr_new)
1114 			continue;
1115 		/* Find a safe value */
1116 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
1117 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
1118 	}
1119 
1120 }
1121 
1122 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
1123 {
1124 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1125 
1126 	if (!regp)
1127 		return 0;
1128 
1129 	update_cpu_ftr_reg(regp, val);
1130 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
1131 		return 0;
1132 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
1133 			regp->name, boot, cpu, val);
1134 	return 1;
1135 }
1136 
1137 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1138 {
1139 	const struct arm64_ftr_bits *ftrp;
1140 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1141 
1142 	if (!regp)
1143 		return;
1144 
1145 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1146 		if (ftrp->shift == field) {
1147 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1148 			break;
1149 		}
1150 	}
1151 
1152 	/* Bogus field? */
1153 	WARN_ON(!ftrp->width);
1154 }
1155 
1156 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1157 					 struct cpuinfo_arm64 *boot)
1158 {
1159 	static bool boot_cpu_32bit_regs_overridden = false;
1160 
1161 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1162 		return;
1163 
1164 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1165 		return;
1166 
1167 	boot->aarch32 = info->aarch32;
1168 	init_32bit_cpu_features(&boot->aarch32);
1169 	boot_cpu_32bit_regs_overridden = true;
1170 }
1171 
1172 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1173 				     struct cpuinfo_32bit *boot)
1174 {
1175 	int taint = 0;
1176 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1177 
1178 	/*
1179 	 * If we don't have AArch32 at EL1, then relax the strictness of
1180 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1181 	 */
1182 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1183 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_EL1_SMC_SHIFT);
1184 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Virt_frac_SHIFT);
1185 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Sec_frac_SHIFT);
1186 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Virtualization_SHIFT);
1187 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Security_SHIFT);
1188 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_ProgMod_SHIFT);
1189 	}
1190 
1191 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1192 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1193 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1194 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1195 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1196 				      info->reg_id_isar0, boot->reg_id_isar0);
1197 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1198 				      info->reg_id_isar1, boot->reg_id_isar1);
1199 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1200 				      info->reg_id_isar2, boot->reg_id_isar2);
1201 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1202 				      info->reg_id_isar3, boot->reg_id_isar3);
1203 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1204 				      info->reg_id_isar4, boot->reg_id_isar4);
1205 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1206 				      info->reg_id_isar5, boot->reg_id_isar5);
1207 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1208 				      info->reg_id_isar6, boot->reg_id_isar6);
1209 
1210 	/*
1211 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1212 	 * ACTLR formats could differ across CPUs and therefore would have to
1213 	 * be trapped for virtualization anyway.
1214 	 */
1215 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1216 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1217 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1218 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1219 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1220 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1221 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1222 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1223 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1224 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1225 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1226 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1227 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1228 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1229 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1230 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1231 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1232 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1233 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1234 				      info->reg_mvfr0, boot->reg_mvfr0);
1235 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1236 				      info->reg_mvfr1, boot->reg_mvfr1);
1237 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1238 				      info->reg_mvfr2, boot->reg_mvfr2);
1239 
1240 	return taint;
1241 }
1242 
1243 /*
1244  * Update system wide CPU feature registers with the values from a
1245  * non-boot CPU. Also performs SANITY checks to make sure that there
1246  * aren't any insane variations from that of the boot CPU.
1247  */
1248 void update_cpu_features(int cpu,
1249 			 struct cpuinfo_arm64 *info,
1250 			 struct cpuinfo_arm64 *boot)
1251 {
1252 	int taint = 0;
1253 
1254 	/*
1255 	 * The kernel can handle differing I-cache policies, but otherwise
1256 	 * caches should look identical. Userspace JITs will make use of
1257 	 * *minLine.
1258 	 */
1259 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1260 				      info->reg_ctr, boot->reg_ctr);
1261 
1262 	/*
1263 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1264 	 * could result in too much or too little memory being zeroed if a
1265 	 * process is preempted and migrated between CPUs.
1266 	 */
1267 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1268 				      info->reg_dczid, boot->reg_dczid);
1269 
1270 	/* If different, timekeeping will be broken (especially with KVM) */
1271 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1272 				      info->reg_cntfrq, boot->reg_cntfrq);
1273 
1274 	/*
1275 	 * The kernel uses self-hosted debug features and expects CPUs to
1276 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1277 	 * and BRPs to be identical.
1278 	 * ID_AA64DFR1 is currently RES0.
1279 	 */
1280 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1281 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1282 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1283 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1284 	/*
1285 	 * Even in big.LITTLE, processors should be identical instruction-set
1286 	 * wise.
1287 	 */
1288 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1289 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1290 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1291 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1292 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1293 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1294 
1295 	/*
1296 	 * Differing PARange support is fine as long as all peripherals and
1297 	 * memory are mapped within the minimum PARange of all CPUs.
1298 	 * Linux should not care about secure memory.
1299 	 */
1300 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1301 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1302 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1303 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1304 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1305 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1306 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR3_EL1, cpu,
1307 				      info->reg_id_aa64mmfr3, boot->reg_id_aa64mmfr3);
1308 
1309 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1310 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1311 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1312 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1313 
1314 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1315 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1316 
1317 	taint |= check_update_ftr_reg(SYS_ID_AA64SMFR0_EL1, cpu,
1318 				      info->reg_id_aa64smfr0, boot->reg_id_aa64smfr0);
1319 
1320 	/* Probe vector lengths */
1321 	if (IS_ENABLED(CONFIG_ARM64_SVE) &&
1322 	    id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1))) {
1323 		if (!system_capabilities_finalized()) {
1324 			unsigned long cpacr = cpacr_save_enable_kernel_sve();
1325 
1326 			vec_update_vq_map(ARM64_VEC_SVE);
1327 
1328 			cpacr_restore(cpacr);
1329 		}
1330 	}
1331 
1332 	if (IS_ENABLED(CONFIG_ARM64_SME) &&
1333 	    id_aa64pfr1_sme(read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1))) {
1334 		unsigned long cpacr = cpacr_save_enable_kernel_sme();
1335 
1336 		/*
1337 		 * We mask out SMPS since even if the hardware
1338 		 * supports priorities the kernel does not at present
1339 		 * and we block access to them.
1340 		 */
1341 		info->reg_smidr = read_cpuid(SMIDR_EL1) & ~SMIDR_EL1_SMPS;
1342 
1343 		/* Probe vector lengths */
1344 		if (!system_capabilities_finalized())
1345 			vec_update_vq_map(ARM64_VEC_SME);
1346 
1347 		cpacr_restore(cpacr);
1348 	}
1349 
1350 	/*
1351 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1352 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1353 	 * value is the same on all CPUs.
1354 	 */
1355 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1356 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1357 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1358 					      info->reg_gmid, boot->reg_gmid);
1359 	}
1360 
1361 	/*
1362 	 * If we don't have AArch32 at all then skip the checks entirely
1363 	 * as the register values may be UNKNOWN and we're not going to be
1364 	 * using them for anything.
1365 	 *
1366 	 * This relies on a sanitised view of the AArch64 ID registers
1367 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1368 	 */
1369 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1370 		lazy_init_32bit_cpu_features(info, boot);
1371 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1372 						   &boot->aarch32);
1373 	}
1374 
1375 	/*
1376 	 * Mismatched CPU features are a recipe for disaster. Don't even
1377 	 * pretend to support them.
1378 	 */
1379 	if (taint) {
1380 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1381 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1382 	}
1383 }
1384 
1385 u64 read_sanitised_ftr_reg(u32 id)
1386 {
1387 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1388 
1389 	if (!regp)
1390 		return 0;
1391 	return regp->sys_val;
1392 }
1393 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1394 
1395 #define read_sysreg_case(r)	\
1396 	case r:		val = read_sysreg_s(r); break;
1397 
1398 /*
1399  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1400  * Read the system register on the current CPU
1401  */
1402 u64 __read_sysreg_by_encoding(u32 sys_id)
1403 {
1404 	struct arm64_ftr_reg *regp;
1405 	u64 val;
1406 
1407 	switch (sys_id) {
1408 	read_sysreg_case(SYS_ID_PFR0_EL1);
1409 	read_sysreg_case(SYS_ID_PFR1_EL1);
1410 	read_sysreg_case(SYS_ID_PFR2_EL1);
1411 	read_sysreg_case(SYS_ID_DFR0_EL1);
1412 	read_sysreg_case(SYS_ID_DFR1_EL1);
1413 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1414 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1415 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1416 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1417 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1418 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1419 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1420 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1421 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1422 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1423 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1424 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1425 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1426 	read_sysreg_case(SYS_MVFR0_EL1);
1427 	read_sysreg_case(SYS_MVFR1_EL1);
1428 	read_sysreg_case(SYS_MVFR2_EL1);
1429 
1430 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1431 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1432 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1433 	read_sysreg_case(SYS_ID_AA64SMFR0_EL1);
1434 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1435 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1436 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1437 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1438 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1439 	read_sysreg_case(SYS_ID_AA64MMFR3_EL1);
1440 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1441 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1442 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1443 
1444 	read_sysreg_case(SYS_CNTFRQ_EL0);
1445 	read_sysreg_case(SYS_CTR_EL0);
1446 	read_sysreg_case(SYS_DCZID_EL0);
1447 
1448 	default:
1449 		BUG();
1450 		return 0;
1451 	}
1452 
1453 	regp  = get_arm64_ftr_reg(sys_id);
1454 	if (regp) {
1455 		val &= ~regp->override->mask;
1456 		val |= (regp->override->val & regp->override->mask);
1457 	}
1458 
1459 	return val;
1460 }
1461 
1462 #include <linux/irqchip/arm-gic-v3.h>
1463 
1464 static bool
1465 has_always(const struct arm64_cpu_capabilities *entry, int scope)
1466 {
1467 	return true;
1468 }
1469 
1470 static bool
1471 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1472 {
1473 	int val = cpuid_feature_extract_field_width(reg, entry->field_pos,
1474 						    entry->field_width,
1475 						    entry->sign);
1476 
1477 	return val >= entry->min_field_value;
1478 }
1479 
1480 static u64
1481 read_scoped_sysreg(const struct arm64_cpu_capabilities *entry, int scope)
1482 {
1483 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1484 	if (scope == SCOPE_SYSTEM)
1485 		return read_sanitised_ftr_reg(entry->sys_reg);
1486 	else
1487 		return __read_sysreg_by_encoding(entry->sys_reg);
1488 }
1489 
1490 static bool
1491 has_user_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1492 {
1493 	int mask;
1494 	struct arm64_ftr_reg *regp;
1495 	u64 val = read_scoped_sysreg(entry, scope);
1496 
1497 	regp = get_arm64_ftr_reg(entry->sys_reg);
1498 	if (!regp)
1499 		return false;
1500 
1501 	mask = cpuid_feature_extract_unsigned_field_width(regp->user_mask,
1502 							  entry->field_pos,
1503 							  entry->field_width);
1504 	if (!mask)
1505 		return false;
1506 
1507 	return feature_matches(val, entry);
1508 }
1509 
1510 static bool
1511 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1512 {
1513 	u64 val = read_scoped_sysreg(entry, scope);
1514 	return feature_matches(val, entry);
1515 }
1516 
1517 const struct cpumask *system_32bit_el0_cpumask(void)
1518 {
1519 	if (!system_supports_32bit_el0())
1520 		return cpu_none_mask;
1521 
1522 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1523 		return cpu_32bit_el0_mask;
1524 
1525 	return cpu_possible_mask;
1526 }
1527 
1528 static int __init parse_32bit_el0_param(char *str)
1529 {
1530 	allow_mismatched_32bit_el0 = true;
1531 	return 0;
1532 }
1533 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1534 
1535 static ssize_t aarch32_el0_show(struct device *dev,
1536 				struct device_attribute *attr, char *buf)
1537 {
1538 	const struct cpumask *mask = system_32bit_el0_cpumask();
1539 
1540 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1541 }
1542 static const DEVICE_ATTR_RO(aarch32_el0);
1543 
1544 static int __init aarch32_el0_sysfs_init(void)
1545 {
1546 	struct device *dev_root;
1547 	int ret = 0;
1548 
1549 	if (!allow_mismatched_32bit_el0)
1550 		return 0;
1551 
1552 	dev_root = bus_get_dev_root(&cpu_subsys);
1553 	if (dev_root) {
1554 		ret = device_create_file(dev_root, &dev_attr_aarch32_el0);
1555 		put_device(dev_root);
1556 	}
1557 	return ret;
1558 }
1559 device_initcall(aarch32_el0_sysfs_init);
1560 
1561 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1562 {
1563 	if (!has_cpuid_feature(entry, scope))
1564 		return allow_mismatched_32bit_el0;
1565 
1566 	if (scope == SCOPE_SYSTEM)
1567 		pr_info("detected: 32-bit EL0 Support\n");
1568 
1569 	return true;
1570 }
1571 
1572 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1573 {
1574 	bool has_sre;
1575 
1576 	if (!has_cpuid_feature(entry, scope))
1577 		return false;
1578 
1579 	has_sre = gic_enable_sre();
1580 	if (!has_sre)
1581 		pr_warn_once("%s present but disabled by higher exception level\n",
1582 			     entry->desc);
1583 
1584 	return has_sre;
1585 }
1586 
1587 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1588 {
1589 	u32 midr = read_cpuid_id();
1590 
1591 	/* Cavium ThunderX pass 1.x and 2.x */
1592 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1593 		MIDR_CPU_VAR_REV(0, 0),
1594 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1595 }
1596 
1597 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1598 			  int scope)
1599 {
1600 	u64 ctr;
1601 
1602 	if (scope == SCOPE_SYSTEM)
1603 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1604 	else
1605 		ctr = read_cpuid_effective_cachetype();
1606 
1607 	return ctr & BIT(CTR_EL0_IDC_SHIFT);
1608 }
1609 
1610 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1611 {
1612 	/*
1613 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1614 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1615 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1616 	 * value.
1617 	 */
1618 	if (!(read_cpuid_cachetype() & BIT(CTR_EL0_IDC_SHIFT)))
1619 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1620 }
1621 
1622 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1623 			  int scope)
1624 {
1625 	u64 ctr;
1626 
1627 	if (scope == SCOPE_SYSTEM)
1628 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1629 	else
1630 		ctr = read_cpuid_cachetype();
1631 
1632 	return ctr & BIT(CTR_EL0_DIC_SHIFT);
1633 }
1634 
1635 static bool __maybe_unused
1636 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1637 {
1638 	/*
1639 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1640 	 * may share TLB entries with a CPU stuck in the crashed
1641 	 * kernel.
1642 	 */
1643 	if (is_kdump_kernel())
1644 		return false;
1645 
1646 	if (cpus_have_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1647 		return false;
1648 
1649 	return has_cpuid_feature(entry, scope);
1650 }
1651 
1652 /*
1653  * This check is triggered during the early boot before the cpufeature
1654  * is initialised. Checking the status on the local CPU allows the boot
1655  * CPU to detect the need for non-global mappings and thus avoiding a
1656  * pagetable re-write after all the CPUs are booted. This check will be
1657  * anyway run on individual CPUs, allowing us to get the consistent
1658  * state once the SMP CPUs are up and thus make the switch to non-global
1659  * mappings if required.
1660  */
1661 bool kaslr_requires_kpti(void)
1662 {
1663 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1664 		return false;
1665 
1666 	/*
1667 	 * E0PD does a similar job to KPTI so can be used instead
1668 	 * where available.
1669 	 */
1670 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1671 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1672 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1673 						ID_AA64MMFR2_EL1_E0PD_SHIFT))
1674 			return false;
1675 	}
1676 
1677 	/*
1678 	 * Systems affected by Cavium erratum 24756 are incompatible
1679 	 * with KPTI.
1680 	 */
1681 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1682 		extern const struct midr_range cavium_erratum_27456_cpus[];
1683 
1684 		if (is_midr_in_range_list(read_cpuid_id(),
1685 					  cavium_erratum_27456_cpus))
1686 			return false;
1687 	}
1688 
1689 	return kaslr_enabled();
1690 }
1691 
1692 static bool __meltdown_safe = true;
1693 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1694 
1695 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1696 				int scope)
1697 {
1698 	/* List of CPUs that are not vulnerable and don't need KPTI */
1699 	static const struct midr_range kpti_safe_list[] = {
1700 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1701 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1702 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1703 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1704 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1705 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1706 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1707 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1708 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1709 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1710 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1711 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1712 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1713 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1714 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1715 		{ /* sentinel */ }
1716 	};
1717 	char const *str = "kpti command line option";
1718 	bool meltdown_safe;
1719 
1720 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1721 
1722 	/* Defer to CPU feature registers */
1723 	if (has_cpuid_feature(entry, scope))
1724 		meltdown_safe = true;
1725 
1726 	if (!meltdown_safe)
1727 		__meltdown_safe = false;
1728 
1729 	/*
1730 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1731 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1732 	 * ends as well as you might imagine. Don't even try. We cannot rely
1733 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1734 	 * because cpucap detection order may change. However, since we know
1735 	 * affected CPUs are always in a homogeneous configuration, it is
1736 	 * safe to rely on this_cpu_has_cap() here.
1737 	 */
1738 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1739 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1740 		__kpti_forced = -1;
1741 	}
1742 
1743 	/* Useful for KASLR robustness */
1744 	if (kaslr_requires_kpti()) {
1745 		if (!__kpti_forced) {
1746 			str = "KASLR";
1747 			__kpti_forced = 1;
1748 		}
1749 	}
1750 
1751 	if (cpu_mitigations_off() && !__kpti_forced) {
1752 		str = "mitigations=off";
1753 		__kpti_forced = -1;
1754 	}
1755 
1756 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1757 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1758 		return false;
1759 	}
1760 
1761 	/* Forced? */
1762 	if (__kpti_forced) {
1763 		pr_info_once("kernel page table isolation forced %s by %s\n",
1764 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1765 		return __kpti_forced > 0;
1766 	}
1767 
1768 	return !meltdown_safe;
1769 }
1770 
1771 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1772 #define KPTI_NG_TEMP_VA		(-(1UL << PMD_SHIFT))
1773 
1774 extern
1775 void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt,
1776 			     phys_addr_t size, pgprot_t prot,
1777 			     phys_addr_t (*pgtable_alloc)(int), int flags);
1778 
1779 static phys_addr_t __initdata kpti_ng_temp_alloc;
1780 
1781 static phys_addr_t __init kpti_ng_pgd_alloc(int shift)
1782 {
1783 	kpti_ng_temp_alloc -= PAGE_SIZE;
1784 	return kpti_ng_temp_alloc;
1785 }
1786 
1787 static int __init __kpti_install_ng_mappings(void *__unused)
1788 {
1789 	typedef void (kpti_remap_fn)(int, int, phys_addr_t, unsigned long);
1790 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1791 	kpti_remap_fn *remap_fn;
1792 
1793 	int cpu = smp_processor_id();
1794 	int levels = CONFIG_PGTABLE_LEVELS;
1795 	int order = order_base_2(levels);
1796 	u64 kpti_ng_temp_pgd_pa = 0;
1797 	pgd_t *kpti_ng_temp_pgd;
1798 	u64 alloc = 0;
1799 
1800 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1801 
1802 	if (!cpu) {
1803 		alloc = __get_free_pages(GFP_ATOMIC | __GFP_ZERO, order);
1804 		kpti_ng_temp_pgd = (pgd_t *)(alloc + (levels - 1) * PAGE_SIZE);
1805 		kpti_ng_temp_alloc = kpti_ng_temp_pgd_pa = __pa(kpti_ng_temp_pgd);
1806 
1807 		//
1808 		// Create a minimal page table hierarchy that permits us to map
1809 		// the swapper page tables temporarily as we traverse them.
1810 		//
1811 		// The physical pages are laid out as follows:
1812 		//
1813 		// +--------+-/-------+-/------ +-\\--------+
1814 		// :  PTE[] : | PMD[] : | PUD[] : || PGD[]  :
1815 		// +--------+-\-------+-\------ +-//--------+
1816 		//      ^
1817 		// The first page is mapped into this hierarchy at a PMD_SHIFT
1818 		// aligned virtual address, so that we can manipulate the PTE
1819 		// level entries while the mapping is active. The first entry
1820 		// covers the PTE[] page itself, the remaining entries are free
1821 		// to be used as a ad-hoc fixmap.
1822 		//
1823 		create_kpti_ng_temp_pgd(kpti_ng_temp_pgd, __pa(alloc),
1824 					KPTI_NG_TEMP_VA, PAGE_SIZE, PAGE_KERNEL,
1825 					kpti_ng_pgd_alloc, 0);
1826 	}
1827 
1828 	cpu_install_idmap();
1829 	remap_fn(cpu, num_online_cpus(), kpti_ng_temp_pgd_pa, KPTI_NG_TEMP_VA);
1830 	cpu_uninstall_idmap();
1831 
1832 	if (!cpu) {
1833 		free_pages(alloc, order);
1834 		arm64_use_ng_mappings = true;
1835 	}
1836 
1837 	return 0;
1838 }
1839 
1840 static void __init kpti_install_ng_mappings(void)
1841 {
1842 	/* Check whether KPTI is going to be used */
1843 	if (!cpus_have_cap(ARM64_UNMAP_KERNEL_AT_EL0))
1844 		return;
1845 
1846 	/*
1847 	 * We don't need to rewrite the page-tables if either we've done
1848 	 * it already or we have KASLR enabled and therefore have not
1849 	 * created any global mappings at all.
1850 	 */
1851 	if (arm64_use_ng_mappings)
1852 		return;
1853 
1854 	stop_machine(__kpti_install_ng_mappings, NULL, cpu_online_mask);
1855 }
1856 
1857 #else
1858 static inline void kpti_install_ng_mappings(void)
1859 {
1860 }
1861 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1862 
1863 static void cpu_enable_kpti(struct arm64_cpu_capabilities const *cap)
1864 {
1865 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1866 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1867 
1868 		__this_cpu_write(this_cpu_vector, v);
1869 	}
1870 
1871 }
1872 
1873 static int __init parse_kpti(char *str)
1874 {
1875 	bool enabled;
1876 	int ret = kstrtobool(str, &enabled);
1877 
1878 	if (ret)
1879 		return ret;
1880 
1881 	__kpti_forced = enabled ? 1 : -1;
1882 	return 0;
1883 }
1884 early_param("kpti", parse_kpti);
1885 
1886 #ifdef CONFIG_ARM64_HW_AFDBM
1887 static struct cpumask dbm_cpus __read_mostly;
1888 
1889 static inline void __cpu_enable_hw_dbm(void)
1890 {
1891 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1892 
1893 	write_sysreg(tcr, tcr_el1);
1894 	isb();
1895 	local_flush_tlb_all();
1896 }
1897 
1898 static bool cpu_has_broken_dbm(void)
1899 {
1900 	/* List of CPUs which have broken DBM support. */
1901 	static const struct midr_range cpus[] = {
1902 #ifdef CONFIG_ARM64_ERRATUM_1024718
1903 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1904 		/* Kryo4xx Silver (rdpe => r1p0) */
1905 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1906 #endif
1907 #ifdef CONFIG_ARM64_ERRATUM_2051678
1908 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1909 #endif
1910 		{},
1911 	};
1912 
1913 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1914 }
1915 
1916 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1917 {
1918 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1919 	       !cpu_has_broken_dbm();
1920 }
1921 
1922 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1923 {
1924 	if (cpu_can_use_dbm(cap)) {
1925 		__cpu_enable_hw_dbm();
1926 		cpumask_set_cpu(smp_processor_id(), &dbm_cpus);
1927 	}
1928 }
1929 
1930 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1931 		       int __unused)
1932 {
1933 	/*
1934 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1935 	 * run a mix of CPUs with and without the feature. So, we
1936 	 * unconditionally enable the capability to allow any late CPU
1937 	 * to use the feature. We only enable the control bits on the
1938 	 * CPU, if it is supported.
1939 	 */
1940 
1941 	return true;
1942 }
1943 
1944 #endif
1945 
1946 #ifdef CONFIG_ARM64_AMU_EXTN
1947 
1948 /*
1949  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1950  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1951  * information regarding all the events that it supports. When a CPU bit is
1952  * set in the cpumask, the user of this feature can only rely on the presence
1953  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1954  * counters are enabled or access to these counters is enabled by code
1955  * executed at higher exception levels (firmware).
1956  */
1957 static struct cpumask amu_cpus __read_mostly;
1958 
1959 bool cpu_has_amu_feat(int cpu)
1960 {
1961 	return cpumask_test_cpu(cpu, &amu_cpus);
1962 }
1963 
1964 int get_cpu_with_amu_feat(void)
1965 {
1966 	return cpumask_any(&amu_cpus);
1967 }
1968 
1969 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1970 {
1971 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1972 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1973 
1974 		/* 0 reference values signal broken/disabled counters */
1975 		if (!this_cpu_has_cap(ARM64_WORKAROUND_2457168))
1976 			update_freq_counters_refs();
1977 	}
1978 }
1979 
1980 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1981 		    int __unused)
1982 {
1983 	/*
1984 	 * The AMU extension is a non-conflicting feature: the kernel can
1985 	 * safely run a mix of CPUs with and without support for the
1986 	 * activity monitors extension. Therefore, unconditionally enable
1987 	 * the capability to allow any late CPU to use the feature.
1988 	 *
1989 	 * With this feature unconditionally enabled, the cpu_enable
1990 	 * function will be called for all CPUs that match the criteria,
1991 	 * including secondary and hotplugged, marking this feature as
1992 	 * present on that respective CPU. The enable function will also
1993 	 * print a detection message.
1994 	 */
1995 
1996 	return true;
1997 }
1998 #else
1999 int get_cpu_with_amu_feat(void)
2000 {
2001 	return nr_cpu_ids;
2002 }
2003 #endif
2004 
2005 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
2006 {
2007 	return is_kernel_in_hyp_mode();
2008 }
2009 
2010 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
2011 {
2012 	/*
2013 	 * Copy register values that aren't redirected by hardware.
2014 	 *
2015 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
2016 	 * this value to tpidr_el2 before we patch the code. Once we've done
2017 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
2018 	 * do anything here.
2019 	 */
2020 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
2021 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
2022 }
2023 
2024 static bool has_nested_virt_support(const struct arm64_cpu_capabilities *cap,
2025 				    int scope)
2026 {
2027 	if (kvm_get_mode() != KVM_MODE_NV)
2028 		return false;
2029 
2030 	if (!has_cpuid_feature(cap, scope)) {
2031 		pr_warn("unavailable: %s\n", cap->desc);
2032 		return false;
2033 	}
2034 
2035 	return true;
2036 }
2037 
2038 static bool hvhe_possible(const struct arm64_cpu_capabilities *entry,
2039 			  int __unused)
2040 {
2041 	u64 val;
2042 
2043 	val = read_sysreg(id_aa64mmfr1_el1);
2044 	if (!cpuid_feature_extract_unsigned_field(val, ID_AA64MMFR1_EL1_VH_SHIFT))
2045 		return false;
2046 
2047 	val = arm64_sw_feature_override.val & arm64_sw_feature_override.mask;
2048 	return cpuid_feature_extract_unsigned_field(val, ARM64_SW_FEATURE_OVERRIDE_HVHE);
2049 }
2050 
2051 #ifdef CONFIG_ARM64_PAN
2052 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
2053 {
2054 	/*
2055 	 * We modify PSTATE. This won't work from irq context as the PSTATE
2056 	 * is discarded once we return from the exception.
2057 	 */
2058 	WARN_ON_ONCE(in_interrupt());
2059 
2060 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
2061 	set_pstate_pan(1);
2062 }
2063 #endif /* CONFIG_ARM64_PAN */
2064 
2065 #ifdef CONFIG_ARM64_RAS_EXTN
2066 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
2067 {
2068 	/* Firmware may have left a deferred SError in this register. */
2069 	write_sysreg_s(0, SYS_DISR_EL1);
2070 }
2071 #endif /* CONFIG_ARM64_RAS_EXTN */
2072 
2073 #ifdef CONFIG_ARM64_PTR_AUTH
2074 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
2075 {
2076 	int boot_val, sec_val;
2077 
2078 	/* We don't expect to be called with SCOPE_SYSTEM */
2079 	WARN_ON(scope == SCOPE_SYSTEM);
2080 	/*
2081 	 * The ptr-auth feature levels are not intercompatible with lower
2082 	 * levels. Hence we must match ptr-auth feature level of the secondary
2083 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
2084 	 * from the sanitised register whereas direct register read is done for
2085 	 * the secondary CPUs.
2086 	 * The sanitised feature state is guaranteed to match that of the
2087 	 * boot CPU as a mismatched secondary CPU is parked before it gets
2088 	 * a chance to update the state, with the capability.
2089 	 */
2090 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
2091 					       entry->field_pos, entry->sign);
2092 	if (scope & SCOPE_BOOT_CPU)
2093 		return boot_val >= entry->min_field_value;
2094 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
2095 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
2096 					      entry->field_pos, entry->sign);
2097 	return (sec_val >= entry->min_field_value) && (sec_val == boot_val);
2098 }
2099 
2100 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
2101 				     int scope)
2102 {
2103 	bool api = has_address_auth_cpucap(cpucap_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
2104 	bool apa = has_address_auth_cpucap(cpucap_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5], scope);
2105 	bool apa3 = has_address_auth_cpucap(cpucap_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3], scope);
2106 
2107 	return apa || apa3 || api;
2108 }
2109 
2110 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
2111 			     int __unused)
2112 {
2113 	bool gpi = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
2114 	bool gpa = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5);
2115 	bool gpa3 = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3);
2116 
2117 	return gpa || gpa3 || gpi;
2118 }
2119 #endif /* CONFIG_ARM64_PTR_AUTH */
2120 
2121 #ifdef CONFIG_ARM64_E0PD
2122 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
2123 {
2124 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
2125 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
2126 }
2127 #endif /* CONFIG_ARM64_E0PD */
2128 
2129 #ifdef CONFIG_ARM64_PSEUDO_NMI
2130 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
2131 				   int scope)
2132 {
2133 	/*
2134 	 * ARM64_HAS_GIC_CPUIF_SYSREGS has a lower index, and is a boot CPU
2135 	 * feature, so will be detected earlier.
2136 	 */
2137 	BUILD_BUG_ON(ARM64_HAS_GIC_PRIO_MASKING <= ARM64_HAS_GIC_CPUIF_SYSREGS);
2138 	if (!cpus_have_cap(ARM64_HAS_GIC_CPUIF_SYSREGS))
2139 		return false;
2140 
2141 	return enable_pseudo_nmi;
2142 }
2143 
2144 static bool has_gic_prio_relaxed_sync(const struct arm64_cpu_capabilities *entry,
2145 				      int scope)
2146 {
2147 	/*
2148 	 * If we're not using priority masking then we won't be poking PMR_EL1,
2149 	 * and there's no need to relax synchronization of writes to it, and
2150 	 * ICC_CTLR_EL1 might not be accessible and we must avoid reads from
2151 	 * that.
2152 	 *
2153 	 * ARM64_HAS_GIC_PRIO_MASKING has a lower index, and is a boot CPU
2154 	 * feature, so will be detected earlier.
2155 	 */
2156 	BUILD_BUG_ON(ARM64_HAS_GIC_PRIO_RELAXED_SYNC <= ARM64_HAS_GIC_PRIO_MASKING);
2157 	if (!cpus_have_cap(ARM64_HAS_GIC_PRIO_MASKING))
2158 		return false;
2159 
2160 	/*
2161 	 * When Priority Mask Hint Enable (PMHE) == 0b0, PMR is not used as a
2162 	 * hint for interrupt distribution, a DSB is not necessary when
2163 	 * unmasking IRQs via PMR, and we can relax the barrier to a NOP.
2164 	 *
2165 	 * Linux itself doesn't use 1:N distribution, so has no need to
2166 	 * set PMHE. The only reason to have it set is if EL3 requires it
2167 	 * (and we can't change it).
2168 	 */
2169 	return (gic_read_ctlr() & ICC_CTLR_EL1_PMHE_MASK) == 0;
2170 }
2171 #endif
2172 
2173 #ifdef CONFIG_ARM64_BTI
2174 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
2175 {
2176 	/*
2177 	 * Use of X16/X17 for tail-calls and trampolines that jump to
2178 	 * function entry points using BR is a requirement for
2179 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
2180 	 * So, be strict and forbid other BRs using other registers to
2181 	 * jump onto a PACIxSP instruction:
2182 	 */
2183 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
2184 	isb();
2185 }
2186 #endif /* CONFIG_ARM64_BTI */
2187 
2188 #ifdef CONFIG_ARM64_MTE
2189 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
2190 {
2191 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
2192 
2193 	mte_cpu_setup();
2194 
2195 	/*
2196 	 * Clear the tags in the zero page. This needs to be done via the
2197 	 * linear map which has the Tagged attribute.
2198 	 */
2199 	if (try_page_mte_tagging(ZERO_PAGE(0))) {
2200 		mte_clear_page_tags(lm_alias(empty_zero_page));
2201 		set_page_mte_tagged(ZERO_PAGE(0));
2202 	}
2203 
2204 	kasan_init_hw_tags_cpu();
2205 }
2206 #endif /* CONFIG_ARM64_MTE */
2207 
2208 static void user_feature_fixup(void)
2209 {
2210 	if (cpus_have_cap(ARM64_WORKAROUND_2658417)) {
2211 		struct arm64_ftr_reg *regp;
2212 
2213 		regp = get_arm64_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2214 		if (regp)
2215 			regp->user_mask &= ~ID_AA64ISAR1_EL1_BF16_MASK;
2216 	}
2217 }
2218 
2219 static void elf_hwcap_fixup(void)
2220 {
2221 #ifdef CONFIG_COMPAT
2222 	if (cpus_have_cap(ARM64_WORKAROUND_1742098))
2223 		compat_elf_hwcap2 &= ~COMPAT_HWCAP2_AES;
2224 #endif /* CONFIG_COMPAT */
2225 }
2226 
2227 #ifdef CONFIG_KVM
2228 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
2229 {
2230 	return kvm_get_mode() == KVM_MODE_PROTECTED;
2231 }
2232 #endif /* CONFIG_KVM */
2233 
2234 static void cpu_trap_el0_impdef(const struct arm64_cpu_capabilities *__unused)
2235 {
2236 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_TIDCP);
2237 }
2238 
2239 static void cpu_enable_dit(const struct arm64_cpu_capabilities *__unused)
2240 {
2241 	set_pstate_dit(1);
2242 }
2243 
2244 static void cpu_enable_mops(const struct arm64_cpu_capabilities *__unused)
2245 {
2246 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_MSCEn);
2247 }
2248 
2249 /* Internal helper functions to match cpu capability type */
2250 static bool
2251 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
2252 {
2253 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
2254 }
2255 
2256 static bool
2257 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
2258 {
2259 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
2260 }
2261 
2262 static bool
2263 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
2264 {
2265 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
2266 }
2267 
2268 static const struct arm64_cpu_capabilities arm64_features[] = {
2269 	{
2270 		.capability = ARM64_ALWAYS_BOOT,
2271 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2272 		.matches = has_always,
2273 	},
2274 	{
2275 		.capability = ARM64_ALWAYS_SYSTEM,
2276 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2277 		.matches = has_always,
2278 	},
2279 	{
2280 		.desc = "GIC system register CPU interface",
2281 		.capability = ARM64_HAS_GIC_CPUIF_SYSREGS,
2282 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2283 		.matches = has_useable_gicv3_cpuif,
2284 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, GIC, IMP)
2285 	},
2286 	{
2287 		.desc = "Enhanced Counter Virtualization",
2288 		.capability = ARM64_HAS_ECV,
2289 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2290 		.matches = has_cpuid_feature,
2291 		ARM64_CPUID_FIELDS(ID_AA64MMFR0_EL1, ECV, IMP)
2292 	},
2293 	{
2294 		.desc = "Enhanced Counter Virtualization (CNTPOFF)",
2295 		.capability = ARM64_HAS_ECV_CNTPOFF,
2296 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2297 		.matches = has_cpuid_feature,
2298 		ARM64_CPUID_FIELDS(ID_AA64MMFR0_EL1, ECV, CNTPOFF)
2299 	},
2300 #ifdef CONFIG_ARM64_PAN
2301 	{
2302 		.desc = "Privileged Access Never",
2303 		.capability = ARM64_HAS_PAN,
2304 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2305 		.matches = has_cpuid_feature,
2306 		.cpu_enable = cpu_enable_pan,
2307 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, IMP)
2308 	},
2309 #endif /* CONFIG_ARM64_PAN */
2310 #ifdef CONFIG_ARM64_EPAN
2311 	{
2312 		.desc = "Enhanced Privileged Access Never",
2313 		.capability = ARM64_HAS_EPAN,
2314 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2315 		.matches = has_cpuid_feature,
2316 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, PAN3)
2317 	},
2318 #endif /* CONFIG_ARM64_EPAN */
2319 #ifdef CONFIG_ARM64_LSE_ATOMICS
2320 	{
2321 		.desc = "LSE atomic instructions",
2322 		.capability = ARM64_HAS_LSE_ATOMICS,
2323 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2324 		.matches = has_cpuid_feature,
2325 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, ATOMIC, IMP)
2326 	},
2327 #endif /* CONFIG_ARM64_LSE_ATOMICS */
2328 	{
2329 		.desc = "Software prefetching using PRFM",
2330 		.capability = ARM64_HAS_NO_HW_PREFETCH,
2331 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2332 		.matches = has_no_hw_prefetch,
2333 	},
2334 	{
2335 		.desc = "Virtualization Host Extensions",
2336 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
2337 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2338 		.matches = runs_at_el2,
2339 		.cpu_enable = cpu_copy_el2regs,
2340 	},
2341 	{
2342 		.desc = "Nested Virtualization Support",
2343 		.capability = ARM64_HAS_NESTED_VIRT,
2344 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2345 		.matches = has_nested_virt_support,
2346 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, NV, IMP)
2347 	},
2348 	{
2349 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2350 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2351 		.matches = has_32bit_el0,
2352 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, EL0, AARCH32)
2353 	},
2354 #ifdef CONFIG_KVM
2355 	{
2356 		.desc = "32-bit EL1 Support",
2357 		.capability = ARM64_HAS_32BIT_EL1,
2358 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2359 		.matches = has_cpuid_feature,
2360 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, EL1, AARCH32)
2361 	},
2362 	{
2363 		.desc = "Protected KVM",
2364 		.capability = ARM64_KVM_PROTECTED_MODE,
2365 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2366 		.matches = is_kvm_protected_mode,
2367 	},
2368 	{
2369 		.desc = "HCRX_EL2 register",
2370 		.capability = ARM64_HAS_HCX,
2371 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2372 		.matches = has_cpuid_feature,
2373 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, HCX, IMP)
2374 	},
2375 #endif
2376 	{
2377 		.desc = "Kernel page table isolation (KPTI)",
2378 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2379 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2380 		.cpu_enable = cpu_enable_kpti,
2381 		.matches = unmap_kernel_at_el0,
2382 		/*
2383 		 * The ID feature fields below are used to indicate that
2384 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2385 		 * more details.
2386 		 */
2387 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, CSV3, IMP)
2388 	},
2389 	{
2390 		.capability = ARM64_HAS_FPSIMD,
2391 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2392 		.matches = has_cpuid_feature,
2393 		.cpu_enable = cpu_enable_fpsimd,
2394 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, FP, IMP)
2395 	},
2396 #ifdef CONFIG_ARM64_PMEM
2397 	{
2398 		.desc = "Data cache clean to Point of Persistence",
2399 		.capability = ARM64_HAS_DCPOP,
2400 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2401 		.matches = has_cpuid_feature,
2402 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, DPB, IMP)
2403 	},
2404 	{
2405 		.desc = "Data cache clean to Point of Deep Persistence",
2406 		.capability = ARM64_HAS_DCPODP,
2407 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2408 		.matches = has_cpuid_feature,
2409 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, DPB, DPB2)
2410 	},
2411 #endif
2412 #ifdef CONFIG_ARM64_SVE
2413 	{
2414 		.desc = "Scalable Vector Extension",
2415 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2416 		.capability = ARM64_SVE,
2417 		.cpu_enable = cpu_enable_sve,
2418 		.matches = has_cpuid_feature,
2419 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, SVE, IMP)
2420 	},
2421 #endif /* CONFIG_ARM64_SVE */
2422 #ifdef CONFIG_ARM64_RAS_EXTN
2423 	{
2424 		.desc = "RAS Extension Support",
2425 		.capability = ARM64_HAS_RAS_EXTN,
2426 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2427 		.matches = has_cpuid_feature,
2428 		.cpu_enable = cpu_clear_disr,
2429 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, RAS, IMP)
2430 	},
2431 #endif /* CONFIG_ARM64_RAS_EXTN */
2432 #ifdef CONFIG_ARM64_AMU_EXTN
2433 	{
2434 		.desc = "Activity Monitors Unit (AMU)",
2435 		.capability = ARM64_HAS_AMU_EXTN,
2436 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2437 		.matches = has_amu,
2438 		.cpu_enable = cpu_amu_enable,
2439 		.cpus = &amu_cpus,
2440 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, AMU, IMP)
2441 	},
2442 #endif /* CONFIG_ARM64_AMU_EXTN */
2443 	{
2444 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2445 		.capability = ARM64_HAS_CACHE_IDC,
2446 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2447 		.matches = has_cache_idc,
2448 		.cpu_enable = cpu_emulate_effective_ctr,
2449 	},
2450 	{
2451 		.desc = "Instruction cache invalidation not required for I/D coherence",
2452 		.capability = ARM64_HAS_CACHE_DIC,
2453 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2454 		.matches = has_cache_dic,
2455 	},
2456 	{
2457 		.desc = "Stage-2 Force Write-Back",
2458 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2459 		.capability = ARM64_HAS_STAGE2_FWB,
2460 		.matches = has_cpuid_feature,
2461 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, FWB, IMP)
2462 	},
2463 	{
2464 		.desc = "ARMv8.4 Translation Table Level",
2465 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2466 		.capability = ARM64_HAS_ARMv8_4_TTL,
2467 		.matches = has_cpuid_feature,
2468 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, TTL, IMP)
2469 	},
2470 	{
2471 		.desc = "TLB range maintenance instructions",
2472 		.capability = ARM64_HAS_TLB_RANGE,
2473 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2474 		.matches = has_cpuid_feature,
2475 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, TLB, RANGE)
2476 	},
2477 #ifdef CONFIG_ARM64_HW_AFDBM
2478 	{
2479 		.desc = "Hardware dirty bit management",
2480 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2481 		.capability = ARM64_HW_DBM,
2482 		.matches = has_hw_dbm,
2483 		.cpu_enable = cpu_enable_hw_dbm,
2484 		.cpus = &dbm_cpus,
2485 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, HAFDBS, DBM)
2486 	},
2487 #endif
2488 	{
2489 		.desc = "CRC32 instructions",
2490 		.capability = ARM64_HAS_CRC32,
2491 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2492 		.matches = has_cpuid_feature,
2493 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, CRC32, IMP)
2494 	},
2495 	{
2496 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2497 		.capability = ARM64_SSBS,
2498 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2499 		.matches = has_cpuid_feature,
2500 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SSBS, IMP)
2501 	},
2502 #ifdef CONFIG_ARM64_CNP
2503 	{
2504 		.desc = "Common not Private translations",
2505 		.capability = ARM64_HAS_CNP,
2506 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2507 		.matches = has_useable_cnp,
2508 		.cpu_enable = cpu_enable_cnp,
2509 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, CnP, IMP)
2510 	},
2511 #endif
2512 	{
2513 		.desc = "Speculation barrier (SB)",
2514 		.capability = ARM64_HAS_SB,
2515 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2516 		.matches = has_cpuid_feature,
2517 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, SB, IMP)
2518 	},
2519 #ifdef CONFIG_ARM64_PTR_AUTH
2520 	{
2521 		.desc = "Address authentication (architected QARMA5 algorithm)",
2522 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5,
2523 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2524 		.matches = has_address_auth_cpucap,
2525 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, APA, PAuth)
2526 	},
2527 	{
2528 		.desc = "Address authentication (architected QARMA3 algorithm)",
2529 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3,
2530 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2531 		.matches = has_address_auth_cpucap,
2532 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, APA3, PAuth)
2533 	},
2534 	{
2535 		.desc = "Address authentication (IMP DEF algorithm)",
2536 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2537 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2538 		.matches = has_address_auth_cpucap,
2539 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, API, PAuth)
2540 	},
2541 	{
2542 		.capability = ARM64_HAS_ADDRESS_AUTH,
2543 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2544 		.matches = has_address_auth_metacap,
2545 	},
2546 	{
2547 		.desc = "Generic authentication (architected QARMA5 algorithm)",
2548 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5,
2549 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2550 		.matches = has_cpuid_feature,
2551 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, GPA, IMP)
2552 	},
2553 	{
2554 		.desc = "Generic authentication (architected QARMA3 algorithm)",
2555 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3,
2556 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2557 		.matches = has_cpuid_feature,
2558 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, GPA3, IMP)
2559 	},
2560 	{
2561 		.desc = "Generic authentication (IMP DEF algorithm)",
2562 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2563 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2564 		.matches = has_cpuid_feature,
2565 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, GPI, IMP)
2566 	},
2567 	{
2568 		.capability = ARM64_HAS_GENERIC_AUTH,
2569 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2570 		.matches = has_generic_auth,
2571 	},
2572 #endif /* CONFIG_ARM64_PTR_AUTH */
2573 #ifdef CONFIG_ARM64_PSEUDO_NMI
2574 	{
2575 		/*
2576 		 * Depends on having GICv3
2577 		 */
2578 		.desc = "IRQ priority masking",
2579 		.capability = ARM64_HAS_GIC_PRIO_MASKING,
2580 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2581 		.matches = can_use_gic_priorities,
2582 	},
2583 	{
2584 		/*
2585 		 * Depends on ARM64_HAS_GIC_PRIO_MASKING
2586 		 */
2587 		.capability = ARM64_HAS_GIC_PRIO_RELAXED_SYNC,
2588 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2589 		.matches = has_gic_prio_relaxed_sync,
2590 	},
2591 #endif
2592 #ifdef CONFIG_ARM64_E0PD
2593 	{
2594 		.desc = "E0PD",
2595 		.capability = ARM64_HAS_E0PD,
2596 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2597 		.cpu_enable = cpu_enable_e0pd,
2598 		.matches = has_cpuid_feature,
2599 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, E0PD, IMP)
2600 	},
2601 #endif
2602 	{
2603 		.desc = "Random Number Generator",
2604 		.capability = ARM64_HAS_RNG,
2605 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2606 		.matches = has_cpuid_feature,
2607 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, RNDR, IMP)
2608 	},
2609 #ifdef CONFIG_ARM64_BTI
2610 	{
2611 		.desc = "Branch Target Identification",
2612 		.capability = ARM64_BTI,
2613 #ifdef CONFIG_ARM64_BTI_KERNEL
2614 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2615 #else
2616 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2617 #endif
2618 		.matches = has_cpuid_feature,
2619 		.cpu_enable = bti_enable,
2620 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, BT, IMP)
2621 	},
2622 #endif
2623 #ifdef CONFIG_ARM64_MTE
2624 	{
2625 		.desc = "Memory Tagging Extension",
2626 		.capability = ARM64_MTE,
2627 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2628 		.matches = has_cpuid_feature,
2629 		.cpu_enable = cpu_enable_mte,
2630 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, MTE, MTE2)
2631 	},
2632 	{
2633 		.desc = "Asymmetric MTE Tag Check Fault",
2634 		.capability = ARM64_MTE_ASYMM,
2635 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2636 		.matches = has_cpuid_feature,
2637 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, MTE, MTE3)
2638 	},
2639 #endif /* CONFIG_ARM64_MTE */
2640 	{
2641 		.desc = "RCpc load-acquire (LDAPR)",
2642 		.capability = ARM64_HAS_LDAPR,
2643 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2644 		.matches = has_cpuid_feature,
2645 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, LRCPC, IMP)
2646 	},
2647 	{
2648 		.desc = "Fine Grained Traps",
2649 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2650 		.capability = ARM64_HAS_FGT,
2651 		.matches = has_cpuid_feature,
2652 		ARM64_CPUID_FIELDS(ID_AA64MMFR0_EL1, FGT, IMP)
2653 	},
2654 #ifdef CONFIG_ARM64_SME
2655 	{
2656 		.desc = "Scalable Matrix Extension",
2657 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2658 		.capability = ARM64_SME,
2659 		.matches = has_cpuid_feature,
2660 		.cpu_enable = cpu_enable_sme,
2661 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SME, IMP)
2662 	},
2663 	/* FA64 should be sorted after the base SME capability */
2664 	{
2665 		.desc = "FA64",
2666 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2667 		.capability = ARM64_SME_FA64,
2668 		.matches = has_cpuid_feature,
2669 		.cpu_enable = cpu_enable_fa64,
2670 		ARM64_CPUID_FIELDS(ID_AA64SMFR0_EL1, FA64, IMP)
2671 	},
2672 	{
2673 		.desc = "SME2",
2674 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2675 		.capability = ARM64_SME2,
2676 		.matches = has_cpuid_feature,
2677 		.cpu_enable = cpu_enable_sme2,
2678 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SME, SME2)
2679 	},
2680 #endif /* CONFIG_ARM64_SME */
2681 	{
2682 		.desc = "WFx with timeout",
2683 		.capability = ARM64_HAS_WFXT,
2684 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2685 		.matches = has_cpuid_feature,
2686 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, WFxT, IMP)
2687 	},
2688 	{
2689 		.desc = "Trap EL0 IMPLEMENTATION DEFINED functionality",
2690 		.capability = ARM64_HAS_TIDCP1,
2691 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2692 		.matches = has_cpuid_feature,
2693 		.cpu_enable = cpu_trap_el0_impdef,
2694 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, TIDCP1, IMP)
2695 	},
2696 	{
2697 		.desc = "Data independent timing control (DIT)",
2698 		.capability = ARM64_HAS_DIT,
2699 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2700 		.matches = has_cpuid_feature,
2701 		.cpu_enable = cpu_enable_dit,
2702 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, DIT, IMP)
2703 	},
2704 	{
2705 		.desc = "Memory Copy and Memory Set instructions",
2706 		.capability = ARM64_HAS_MOPS,
2707 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2708 		.matches = has_cpuid_feature,
2709 		.cpu_enable = cpu_enable_mops,
2710 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, MOPS, IMP)
2711 	},
2712 	{
2713 		.capability = ARM64_HAS_TCR2,
2714 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2715 		.matches = has_cpuid_feature,
2716 		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, TCRX, IMP)
2717 	},
2718 	{
2719 		.desc = "Stage-1 Permission Indirection Extension (S1PIE)",
2720 		.capability = ARM64_HAS_S1PIE,
2721 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2722 		.matches = has_cpuid_feature,
2723 		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, S1PIE, IMP)
2724 	},
2725 	{
2726 		.desc = "VHE for hypervisor only",
2727 		.capability = ARM64_KVM_HVHE,
2728 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2729 		.matches = hvhe_possible,
2730 	},
2731 	{
2732 		.desc = "Enhanced Virtualization Traps",
2733 		.capability = ARM64_HAS_EVT,
2734 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2735 		.matches = has_cpuid_feature,
2736 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, EVT, IMP)
2737 	},
2738 	{},
2739 };
2740 
2741 #define HWCAP_CPUID_MATCH(reg, field, min_value)			\
2742 		.matches = has_user_cpuid_feature,			\
2743 		ARM64_CPUID_FIELDS(reg, field, min_value)
2744 
2745 #define __HWCAP_CAP(name, cap_type, cap)					\
2746 		.desc = name,							\
2747 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2748 		.hwcap_type = cap_type,						\
2749 		.hwcap = cap,							\
2750 
2751 #define HWCAP_CAP(reg, field, min_value, cap_type, cap)		\
2752 	{									\
2753 		__HWCAP_CAP(#cap, cap_type, cap)				\
2754 		HWCAP_CPUID_MATCH(reg, field, min_value) 		\
2755 	}
2756 
2757 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2758 	{									\
2759 		__HWCAP_CAP(#cap, cap_type, cap)				\
2760 		.matches = cpucap_multi_entry_cap_matches,			\
2761 		.match_list = list,						\
2762 	}
2763 
2764 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2765 	{									\
2766 		__HWCAP_CAP(#cap, cap_type, cap)				\
2767 		.matches = match,						\
2768 	}
2769 
2770 #ifdef CONFIG_ARM64_PTR_AUTH
2771 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2772 	{
2773 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, APA, PAuth)
2774 	},
2775 	{
2776 		HWCAP_CPUID_MATCH(ID_AA64ISAR2_EL1, APA3, PAuth)
2777 	},
2778 	{
2779 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, API, PAuth)
2780 	},
2781 	{},
2782 };
2783 
2784 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2785 	{
2786 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, GPA, IMP)
2787 	},
2788 	{
2789 		HWCAP_CPUID_MATCH(ID_AA64ISAR2_EL1, GPA3, IMP)
2790 	},
2791 	{
2792 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, GPI, IMP)
2793 	},
2794 	{},
2795 };
2796 #endif
2797 
2798 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2799 	HWCAP_CAP(ID_AA64ISAR0_EL1, AES, PMULL, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2800 	HWCAP_CAP(ID_AA64ISAR0_EL1, AES, AES, CAP_HWCAP, KERNEL_HWCAP_AES),
2801 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA1, IMP, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2802 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA2, SHA256, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2803 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA2, SHA512, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2804 	HWCAP_CAP(ID_AA64ISAR0_EL1, CRC32, IMP, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2805 	HWCAP_CAP(ID_AA64ISAR0_EL1, ATOMIC, IMP, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2806 	HWCAP_CAP(ID_AA64ISAR0_EL1, ATOMIC, FEAT_LSE128, CAP_HWCAP, KERNEL_HWCAP_LSE128),
2807 	HWCAP_CAP(ID_AA64ISAR0_EL1, RDM, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2808 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA3, IMP, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2809 	HWCAP_CAP(ID_AA64ISAR0_EL1, SM3, IMP, CAP_HWCAP, KERNEL_HWCAP_SM3),
2810 	HWCAP_CAP(ID_AA64ISAR0_EL1, SM4, IMP, CAP_HWCAP, KERNEL_HWCAP_SM4),
2811 	HWCAP_CAP(ID_AA64ISAR0_EL1, DP, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2812 	HWCAP_CAP(ID_AA64ISAR0_EL1, FHM, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2813 	HWCAP_CAP(ID_AA64ISAR0_EL1, TS, FLAGM, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2814 	HWCAP_CAP(ID_AA64ISAR0_EL1, TS, FLAGM2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2815 	HWCAP_CAP(ID_AA64ISAR0_EL1, RNDR, IMP, CAP_HWCAP, KERNEL_HWCAP_RNG),
2816 	HWCAP_CAP(ID_AA64PFR0_EL1, FP, IMP, CAP_HWCAP, KERNEL_HWCAP_FP),
2817 	HWCAP_CAP(ID_AA64PFR0_EL1, FP, FP16, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2818 	HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2819 	HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, FP16, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2820 	HWCAP_CAP(ID_AA64PFR0_EL1, DIT, IMP, CAP_HWCAP, KERNEL_HWCAP_DIT),
2821 	HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, IMP, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2822 	HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, DPB2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2823 	HWCAP_CAP(ID_AA64ISAR1_EL1, JSCVT, IMP, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2824 	HWCAP_CAP(ID_AA64ISAR1_EL1, FCMA, IMP, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2825 	HWCAP_CAP(ID_AA64ISAR1_EL1, LRCPC, IMP, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2826 	HWCAP_CAP(ID_AA64ISAR1_EL1, LRCPC, LRCPC2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2827 	HWCAP_CAP(ID_AA64ISAR1_EL1, LRCPC, LRCPC3, CAP_HWCAP, KERNEL_HWCAP_LRCPC3),
2828 	HWCAP_CAP(ID_AA64ISAR1_EL1, FRINTTS, IMP, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2829 	HWCAP_CAP(ID_AA64ISAR1_EL1, SB, IMP, CAP_HWCAP, KERNEL_HWCAP_SB),
2830 	HWCAP_CAP(ID_AA64ISAR1_EL1, BF16, IMP, CAP_HWCAP, KERNEL_HWCAP_BF16),
2831 	HWCAP_CAP(ID_AA64ISAR1_EL1, BF16, EBF16, CAP_HWCAP, KERNEL_HWCAP_EBF16),
2832 	HWCAP_CAP(ID_AA64ISAR1_EL1, DGH, IMP, CAP_HWCAP, KERNEL_HWCAP_DGH),
2833 	HWCAP_CAP(ID_AA64ISAR1_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2834 	HWCAP_CAP(ID_AA64MMFR2_EL1, AT, IMP, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2835 #ifdef CONFIG_ARM64_SVE
2836 	HWCAP_CAP(ID_AA64PFR0_EL1, SVE, IMP, CAP_HWCAP, KERNEL_HWCAP_SVE),
2837 	HWCAP_CAP(ID_AA64ZFR0_EL1, SVEver, SVE2p1, CAP_HWCAP, KERNEL_HWCAP_SVE2P1),
2838 	HWCAP_CAP(ID_AA64ZFR0_EL1, SVEver, SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2839 	HWCAP_CAP(ID_AA64ZFR0_EL1, AES, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2840 	HWCAP_CAP(ID_AA64ZFR0_EL1, AES, PMULL128, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2841 	HWCAP_CAP(ID_AA64ZFR0_EL1, BitPerm, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2842 	HWCAP_CAP(ID_AA64ZFR0_EL1, B16B16, IMP, CAP_HWCAP, KERNEL_HWCAP_SVE_B16B16),
2843 	HWCAP_CAP(ID_AA64ZFR0_EL1, BF16, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2844 	HWCAP_CAP(ID_AA64ZFR0_EL1, BF16, EBF16, CAP_HWCAP, KERNEL_HWCAP_SVE_EBF16),
2845 	HWCAP_CAP(ID_AA64ZFR0_EL1, SHA3, IMP, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2846 	HWCAP_CAP(ID_AA64ZFR0_EL1, SM4, IMP, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2847 	HWCAP_CAP(ID_AA64ZFR0_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2848 	HWCAP_CAP(ID_AA64ZFR0_EL1, F32MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2849 	HWCAP_CAP(ID_AA64ZFR0_EL1, F64MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2850 #endif
2851 	HWCAP_CAP(ID_AA64PFR1_EL1, SSBS, SSBS2, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2852 #ifdef CONFIG_ARM64_BTI
2853 	HWCAP_CAP(ID_AA64PFR1_EL1, BT, IMP, CAP_HWCAP, KERNEL_HWCAP_BTI),
2854 #endif
2855 #ifdef CONFIG_ARM64_PTR_AUTH
2856 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2857 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2858 #endif
2859 #ifdef CONFIG_ARM64_MTE
2860 	HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE2, CAP_HWCAP, KERNEL_HWCAP_MTE),
2861 	HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE3, CAP_HWCAP, KERNEL_HWCAP_MTE3),
2862 #endif /* CONFIG_ARM64_MTE */
2863 	HWCAP_CAP(ID_AA64MMFR0_EL1, ECV, IMP, CAP_HWCAP, KERNEL_HWCAP_ECV),
2864 	HWCAP_CAP(ID_AA64MMFR1_EL1, AFP, IMP, CAP_HWCAP, KERNEL_HWCAP_AFP),
2865 	HWCAP_CAP(ID_AA64ISAR2_EL1, CSSC, IMP, CAP_HWCAP, KERNEL_HWCAP_CSSC),
2866 	HWCAP_CAP(ID_AA64ISAR2_EL1, RPRFM, IMP, CAP_HWCAP, KERNEL_HWCAP_RPRFM),
2867 	HWCAP_CAP(ID_AA64ISAR2_EL1, RPRES, IMP, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2868 	HWCAP_CAP(ID_AA64ISAR2_EL1, WFxT, IMP, CAP_HWCAP, KERNEL_HWCAP_WFXT),
2869 	HWCAP_CAP(ID_AA64ISAR2_EL1, MOPS, IMP, CAP_HWCAP, KERNEL_HWCAP_MOPS),
2870 	HWCAP_CAP(ID_AA64ISAR2_EL1, BC, IMP, CAP_HWCAP, KERNEL_HWCAP_HBC),
2871 #ifdef CONFIG_ARM64_SME
2872 	HWCAP_CAP(ID_AA64PFR1_EL1, SME, IMP, CAP_HWCAP, KERNEL_HWCAP_SME),
2873 	HWCAP_CAP(ID_AA64SMFR0_EL1, FA64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_FA64),
2874 	HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2p1, CAP_HWCAP, KERNEL_HWCAP_SME2P1),
2875 	HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2, CAP_HWCAP, KERNEL_HWCAP_SME2),
2876 	HWCAP_CAP(ID_AA64SMFR0_EL1, I16I64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I64),
2877 	HWCAP_CAP(ID_AA64SMFR0_EL1, F64F64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F64F64),
2878 	HWCAP_CAP(ID_AA64SMFR0_EL1, I16I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I32),
2879 	HWCAP_CAP(ID_AA64SMFR0_EL1, B16B16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16B16),
2880 	HWCAP_CAP(ID_AA64SMFR0_EL1, F16F16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F16),
2881 	HWCAP_CAP(ID_AA64SMFR0_EL1, I8I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I8I32),
2882 	HWCAP_CAP(ID_AA64SMFR0_EL1, F16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F32),
2883 	HWCAP_CAP(ID_AA64SMFR0_EL1, B16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16F32),
2884 	HWCAP_CAP(ID_AA64SMFR0_EL1, BI32I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_BI32I32),
2885 	HWCAP_CAP(ID_AA64SMFR0_EL1, F32F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F32F32),
2886 #endif /* CONFIG_ARM64_SME */
2887 	{},
2888 };
2889 
2890 #ifdef CONFIG_COMPAT
2891 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2892 {
2893 	/*
2894 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2895 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2896 	 * check is future proof, by making sure value is non-zero.
2897 	 */
2898 	u32 mvfr1;
2899 
2900 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2901 	if (scope == SCOPE_SYSTEM)
2902 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2903 	else
2904 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2905 
2906 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDSP_SHIFT) &&
2907 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDInt_SHIFT) &&
2908 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDLS_SHIFT);
2909 }
2910 #endif
2911 
2912 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2913 #ifdef CONFIG_COMPAT
2914 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2915 	HWCAP_CAP(MVFR1_EL1, SIMDFMAC, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2916 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2917 	HWCAP_CAP(MVFR0_EL1, FPDP, VFPv3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2918 	HWCAP_CAP(MVFR0_EL1, FPDP, VFPv3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2919 	HWCAP_CAP(MVFR1_EL1, FPHP, FP16, CAP_COMPAT_HWCAP, COMPAT_HWCAP_FPHP),
2920 	HWCAP_CAP(MVFR1_EL1, SIMDHP, SIMDHP_FLOAT, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDHP),
2921 	HWCAP_CAP(ID_ISAR5_EL1, AES, VMULL, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2922 	HWCAP_CAP(ID_ISAR5_EL1, AES, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2923 	HWCAP_CAP(ID_ISAR5_EL1, SHA1, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2924 	HWCAP_CAP(ID_ISAR5_EL1, SHA2, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2925 	HWCAP_CAP(ID_ISAR5_EL1, CRC32, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2926 	HWCAP_CAP(ID_ISAR6_EL1, DP, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDDP),
2927 	HWCAP_CAP(ID_ISAR6_EL1, FHM, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDFHM),
2928 	HWCAP_CAP(ID_ISAR6_EL1, SB, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SB),
2929 	HWCAP_CAP(ID_ISAR6_EL1, BF16, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDBF16),
2930 	HWCAP_CAP(ID_ISAR6_EL1, I8MM, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_I8MM),
2931 	HWCAP_CAP(ID_PFR2_EL1, SSBS, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SSBS),
2932 #endif
2933 	{},
2934 };
2935 
2936 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2937 {
2938 	switch (cap->hwcap_type) {
2939 	case CAP_HWCAP:
2940 		cpu_set_feature(cap->hwcap);
2941 		break;
2942 #ifdef CONFIG_COMPAT
2943 	case CAP_COMPAT_HWCAP:
2944 		compat_elf_hwcap |= (u32)cap->hwcap;
2945 		break;
2946 	case CAP_COMPAT_HWCAP2:
2947 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2948 		break;
2949 #endif
2950 	default:
2951 		WARN_ON(1);
2952 		break;
2953 	}
2954 }
2955 
2956 /* Check if we have a particular HWCAP enabled */
2957 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2958 {
2959 	bool rc;
2960 
2961 	switch (cap->hwcap_type) {
2962 	case CAP_HWCAP:
2963 		rc = cpu_have_feature(cap->hwcap);
2964 		break;
2965 #ifdef CONFIG_COMPAT
2966 	case CAP_COMPAT_HWCAP:
2967 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2968 		break;
2969 	case CAP_COMPAT_HWCAP2:
2970 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2971 		break;
2972 #endif
2973 	default:
2974 		WARN_ON(1);
2975 		rc = false;
2976 	}
2977 
2978 	return rc;
2979 }
2980 
2981 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2982 {
2983 	/* We support emulation of accesses to CPU ID feature registers */
2984 	cpu_set_named_feature(CPUID);
2985 	for (; hwcaps->matches; hwcaps++)
2986 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2987 			cap_set_elf_hwcap(hwcaps);
2988 }
2989 
2990 static void update_cpu_capabilities(u16 scope_mask)
2991 {
2992 	int i;
2993 	const struct arm64_cpu_capabilities *caps;
2994 
2995 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2996 	for (i = 0; i < ARM64_NCAPS; i++) {
2997 		caps = cpucap_ptrs[i];
2998 		if (!caps || !(caps->type & scope_mask) ||
2999 		    cpus_have_cap(caps->capability) ||
3000 		    !caps->matches(caps, cpucap_default_scope(caps)))
3001 			continue;
3002 
3003 		if (caps->desc && !caps->cpus)
3004 			pr_info("detected: %s\n", caps->desc);
3005 
3006 		__set_bit(caps->capability, system_cpucaps);
3007 
3008 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
3009 			set_bit(caps->capability, boot_cpucaps);
3010 	}
3011 }
3012 
3013 /*
3014  * Enable all the available capabilities on this CPU. The capabilities
3015  * with BOOT_CPU scope are handled separately and hence skipped here.
3016  */
3017 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
3018 {
3019 	int i;
3020 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
3021 
3022 	for_each_available_cap(i) {
3023 		const struct arm64_cpu_capabilities *cap = cpucap_ptrs[i];
3024 
3025 		if (WARN_ON(!cap))
3026 			continue;
3027 
3028 		if (!(cap->type & non_boot_scope))
3029 			continue;
3030 
3031 		if (cap->cpu_enable)
3032 			cap->cpu_enable(cap);
3033 	}
3034 	return 0;
3035 }
3036 
3037 /*
3038  * Run through the enabled capabilities and enable() it on all active
3039  * CPUs
3040  */
3041 static void __init enable_cpu_capabilities(u16 scope_mask)
3042 {
3043 	int i;
3044 	const struct arm64_cpu_capabilities *caps;
3045 	bool boot_scope;
3046 
3047 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
3048 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
3049 
3050 	for (i = 0; i < ARM64_NCAPS; i++) {
3051 		unsigned int num;
3052 
3053 		caps = cpucap_ptrs[i];
3054 		if (!caps || !(caps->type & scope_mask))
3055 			continue;
3056 		num = caps->capability;
3057 		if (!cpus_have_cap(num))
3058 			continue;
3059 
3060 		if (boot_scope && caps->cpu_enable)
3061 			/*
3062 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
3063 			 * before any secondary CPU boots. Thus, each secondary
3064 			 * will enable the capability as appropriate via
3065 			 * check_local_cpu_capabilities(). The only exception is
3066 			 * the boot CPU, for which the capability must be
3067 			 * enabled here. This approach avoids costly
3068 			 * stop_machine() calls for this case.
3069 			 */
3070 			caps->cpu_enable(caps);
3071 	}
3072 
3073 	/*
3074 	 * For all non-boot scope capabilities, use stop_machine()
3075 	 * as it schedules the work allowing us to modify PSTATE,
3076 	 * instead of on_each_cpu() which uses an IPI, giving us a
3077 	 * PSTATE that disappears when we return.
3078 	 */
3079 	if (!boot_scope)
3080 		stop_machine(cpu_enable_non_boot_scope_capabilities,
3081 			     NULL, cpu_online_mask);
3082 }
3083 
3084 /*
3085  * Run through the list of capabilities to check for conflicts.
3086  * If the system has already detected a capability, take necessary
3087  * action on this CPU.
3088  */
3089 static void verify_local_cpu_caps(u16 scope_mask)
3090 {
3091 	int i;
3092 	bool cpu_has_cap, system_has_cap;
3093 	const struct arm64_cpu_capabilities *caps;
3094 
3095 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
3096 
3097 	for (i = 0; i < ARM64_NCAPS; i++) {
3098 		caps = cpucap_ptrs[i];
3099 		if (!caps || !(caps->type & scope_mask))
3100 			continue;
3101 
3102 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
3103 		system_has_cap = cpus_have_cap(caps->capability);
3104 
3105 		if (system_has_cap) {
3106 			/*
3107 			 * Check if the new CPU misses an advertised feature,
3108 			 * which is not safe to miss.
3109 			 */
3110 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
3111 				break;
3112 			/*
3113 			 * We have to issue cpu_enable() irrespective of
3114 			 * whether the CPU has it or not, as it is enabeld
3115 			 * system wide. It is upto the call back to take
3116 			 * appropriate action on this CPU.
3117 			 */
3118 			if (caps->cpu_enable)
3119 				caps->cpu_enable(caps);
3120 		} else {
3121 			/*
3122 			 * Check if the CPU has this capability if it isn't
3123 			 * safe to have when the system doesn't.
3124 			 */
3125 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
3126 				break;
3127 		}
3128 	}
3129 
3130 	if (i < ARM64_NCAPS) {
3131 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
3132 			smp_processor_id(), caps->capability,
3133 			caps->desc, system_has_cap, cpu_has_cap);
3134 
3135 		if (cpucap_panic_on_conflict(caps))
3136 			cpu_panic_kernel();
3137 		else
3138 			cpu_die_early();
3139 	}
3140 }
3141 
3142 /*
3143  * Check for CPU features that are used in early boot
3144  * based on the Boot CPU value.
3145  */
3146 static void check_early_cpu_features(void)
3147 {
3148 	verify_cpu_asid_bits();
3149 
3150 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
3151 }
3152 
3153 static void
3154 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
3155 {
3156 
3157 	for (; caps->matches; caps++)
3158 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
3159 			pr_crit("CPU%d: missing HWCAP: %s\n",
3160 					smp_processor_id(), caps->desc);
3161 			cpu_die_early();
3162 		}
3163 }
3164 
3165 static void verify_local_elf_hwcaps(void)
3166 {
3167 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
3168 
3169 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
3170 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
3171 }
3172 
3173 static void verify_sve_features(void)
3174 {
3175 	unsigned long cpacr = cpacr_save_enable_kernel_sve();
3176 
3177 	if (vec_verify_vq_map(ARM64_VEC_SVE)) {
3178 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
3179 			smp_processor_id());
3180 		cpu_die_early();
3181 	}
3182 
3183 	cpacr_restore(cpacr);
3184 }
3185 
3186 static void verify_sme_features(void)
3187 {
3188 	unsigned long cpacr = cpacr_save_enable_kernel_sme();
3189 
3190 	if (vec_verify_vq_map(ARM64_VEC_SME)) {
3191 		pr_crit("CPU%d: SME: vector length support mismatch\n",
3192 			smp_processor_id());
3193 		cpu_die_early();
3194 	}
3195 
3196 	cpacr_restore(cpacr);
3197 }
3198 
3199 static void verify_hyp_capabilities(void)
3200 {
3201 	u64 safe_mmfr1, mmfr0, mmfr1;
3202 	int parange, ipa_max;
3203 	unsigned int safe_vmid_bits, vmid_bits;
3204 
3205 	if (!IS_ENABLED(CONFIG_KVM))
3206 		return;
3207 
3208 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
3209 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
3210 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
3211 
3212 	/* Verify VMID bits */
3213 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
3214 	vmid_bits = get_vmid_bits(mmfr1);
3215 	if (vmid_bits < safe_vmid_bits) {
3216 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
3217 		cpu_die_early();
3218 	}
3219 
3220 	/* Verify IPA range */
3221 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
3222 				ID_AA64MMFR0_EL1_PARANGE_SHIFT);
3223 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
3224 	if (ipa_max < get_kvm_ipa_limit()) {
3225 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
3226 		cpu_die_early();
3227 	}
3228 }
3229 
3230 /*
3231  * Run through the enabled system capabilities and enable() it on this CPU.
3232  * The capabilities were decided based on the available CPUs at the boot time.
3233  * Any new CPU should match the system wide status of the capability. If the
3234  * new CPU doesn't have a capability which the system now has enabled, we
3235  * cannot do anything to fix it up and could cause unexpected failures. So
3236  * we park the CPU.
3237  */
3238 static void verify_local_cpu_capabilities(void)
3239 {
3240 	/*
3241 	 * The capabilities with SCOPE_BOOT_CPU are checked from
3242 	 * check_early_cpu_features(), as they need to be verified
3243 	 * on all secondary CPUs.
3244 	 */
3245 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3246 	verify_local_elf_hwcaps();
3247 
3248 	if (system_supports_sve())
3249 		verify_sve_features();
3250 
3251 	if (system_supports_sme())
3252 		verify_sme_features();
3253 
3254 	if (is_hyp_mode_available())
3255 		verify_hyp_capabilities();
3256 }
3257 
3258 void check_local_cpu_capabilities(void)
3259 {
3260 	/*
3261 	 * All secondary CPUs should conform to the early CPU features
3262 	 * in use by the kernel based on boot CPU.
3263 	 */
3264 	check_early_cpu_features();
3265 
3266 	/*
3267 	 * If we haven't finalised the system capabilities, this CPU gets
3268 	 * a chance to update the errata work arounds and local features.
3269 	 * Otherwise, this CPU should verify that it has all the system
3270 	 * advertised capabilities.
3271 	 */
3272 	if (!system_capabilities_finalized())
3273 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
3274 	else
3275 		verify_local_cpu_capabilities();
3276 }
3277 
3278 static void __init setup_boot_cpu_capabilities(void)
3279 {
3280 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
3281 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
3282 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
3283 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
3284 }
3285 
3286 bool this_cpu_has_cap(unsigned int n)
3287 {
3288 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
3289 		const struct arm64_cpu_capabilities *cap = cpucap_ptrs[n];
3290 
3291 		if (cap)
3292 			return cap->matches(cap, SCOPE_LOCAL_CPU);
3293 	}
3294 
3295 	return false;
3296 }
3297 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
3298 
3299 /*
3300  * This helper function is used in a narrow window when,
3301  * - The system wide safe registers are set with all the SMP CPUs and,
3302  * - The SYSTEM_FEATURE system_cpucaps may not have been set.
3303  */
3304 static bool __maybe_unused __system_matches_cap(unsigned int n)
3305 {
3306 	if (n < ARM64_NCAPS) {
3307 		const struct arm64_cpu_capabilities *cap = cpucap_ptrs[n];
3308 
3309 		if (cap)
3310 			return cap->matches(cap, SCOPE_SYSTEM);
3311 	}
3312 	return false;
3313 }
3314 
3315 void cpu_set_feature(unsigned int num)
3316 {
3317 	set_bit(num, elf_hwcap);
3318 }
3319 
3320 bool cpu_have_feature(unsigned int num)
3321 {
3322 	return test_bit(num, elf_hwcap);
3323 }
3324 EXPORT_SYMBOL_GPL(cpu_have_feature);
3325 
3326 unsigned long cpu_get_elf_hwcap(void)
3327 {
3328 	/*
3329 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
3330 	 * note that for userspace compatibility we guarantee that bits 62
3331 	 * and 63 will always be returned as 0.
3332 	 */
3333 	return elf_hwcap[0];
3334 }
3335 
3336 unsigned long cpu_get_elf_hwcap2(void)
3337 {
3338 	return elf_hwcap[1];
3339 }
3340 
3341 void __init setup_system_features(void)
3342 {
3343 	int i;
3344 	/*
3345 	 * The system-wide safe feature feature register values have been
3346 	 * finalized. Finalize and log the available system capabilities.
3347 	 */
3348 	update_cpu_capabilities(SCOPE_SYSTEM);
3349 	if (IS_ENABLED(CONFIG_ARM64_SW_TTBR0_PAN) &&
3350 	    !cpus_have_cap(ARM64_HAS_PAN))
3351 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
3352 
3353 	/*
3354 	 * Enable all the available capabilities which have not been enabled
3355 	 * already.
3356 	 */
3357 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3358 
3359 	kpti_install_ng_mappings();
3360 
3361 	sve_setup();
3362 	sme_setup();
3363 
3364 	/*
3365 	 * Check for sane CTR_EL0.CWG value.
3366 	 */
3367 	if (!cache_type_cwg())
3368 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
3369 			ARCH_DMA_MINALIGN);
3370 
3371 	for (i = 0; i < ARM64_NCAPS; i++) {
3372 		const struct arm64_cpu_capabilities *caps = cpucap_ptrs[i];
3373 
3374 		if (caps && caps->cpus && caps->desc &&
3375 			cpumask_any(caps->cpus) < nr_cpu_ids)
3376 			pr_info("detected: %s on CPU%*pbl\n",
3377 				caps->desc, cpumask_pr_args(caps->cpus));
3378 	}
3379 }
3380 
3381 void __init setup_user_features(void)
3382 {
3383 	user_feature_fixup();
3384 
3385 	setup_elf_hwcaps(arm64_elf_hwcaps);
3386 
3387 	if (system_supports_32bit_el0()) {
3388 		setup_elf_hwcaps(compat_elf_hwcaps);
3389 		elf_hwcap_fixup();
3390 	}
3391 
3392 	minsigstksz_setup();
3393 }
3394 
3395 static int enable_mismatched_32bit_el0(unsigned int cpu)
3396 {
3397 	/*
3398 	 * The first 32-bit-capable CPU we detected and so can no longer
3399 	 * be offlined by userspace. -1 indicates we haven't yet onlined
3400 	 * a 32-bit-capable CPU.
3401 	 */
3402 	static int lucky_winner = -1;
3403 
3404 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
3405 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
3406 
3407 	if (cpu_32bit) {
3408 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
3409 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
3410 	}
3411 
3412 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
3413 		return 0;
3414 
3415 	if (lucky_winner >= 0)
3416 		return 0;
3417 
3418 	/*
3419 	 * We've detected a mismatch. We need to keep one of our CPUs with
3420 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
3421 	 * every CPU in the system for a 32-bit task.
3422 	 */
3423 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
3424 							 cpu_active_mask);
3425 	get_cpu_device(lucky_winner)->offline_disabled = true;
3426 	setup_elf_hwcaps(compat_elf_hwcaps);
3427 	elf_hwcap_fixup();
3428 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
3429 		cpu, lucky_winner);
3430 	return 0;
3431 }
3432 
3433 static int __init init_32bit_el0_mask(void)
3434 {
3435 	if (!allow_mismatched_32bit_el0)
3436 		return 0;
3437 
3438 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3439 		return -ENOMEM;
3440 
3441 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3442 				 "arm64/mismatched_32bit_el0:online",
3443 				 enable_mismatched_32bit_el0, NULL);
3444 }
3445 subsys_initcall_sync(init_32bit_el0_mask);
3446 
3447 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3448 {
3449 	cpu_enable_swapper_cnp();
3450 }
3451 
3452 /*
3453  * We emulate only the following system register space.
3454  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 2 - 7]
3455  * See Table C5-6 System instruction encodings for System register accesses,
3456  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3457  */
3458 static inline bool __attribute_const__ is_emulated(u32 id)
3459 {
3460 	return (sys_reg_Op0(id) == 0x3 &&
3461 		sys_reg_CRn(id) == 0x0 &&
3462 		sys_reg_Op1(id) == 0x0 &&
3463 		(sys_reg_CRm(id) == 0 ||
3464 		 ((sys_reg_CRm(id) >= 2) && (sys_reg_CRm(id) <= 7))));
3465 }
3466 
3467 /*
3468  * With CRm == 0, reg should be one of :
3469  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3470  */
3471 static inline int emulate_id_reg(u32 id, u64 *valp)
3472 {
3473 	switch (id) {
3474 	case SYS_MIDR_EL1:
3475 		*valp = read_cpuid_id();
3476 		break;
3477 	case SYS_MPIDR_EL1:
3478 		*valp = SYS_MPIDR_SAFE_VAL;
3479 		break;
3480 	case SYS_REVIDR_EL1:
3481 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3482 		*valp = 0;
3483 		break;
3484 	default:
3485 		return -EINVAL;
3486 	}
3487 
3488 	return 0;
3489 }
3490 
3491 static int emulate_sys_reg(u32 id, u64 *valp)
3492 {
3493 	struct arm64_ftr_reg *regp;
3494 
3495 	if (!is_emulated(id))
3496 		return -EINVAL;
3497 
3498 	if (sys_reg_CRm(id) == 0)
3499 		return emulate_id_reg(id, valp);
3500 
3501 	regp = get_arm64_ftr_reg_nowarn(id);
3502 	if (regp)
3503 		*valp = arm64_ftr_reg_user_value(regp);
3504 	else
3505 		/*
3506 		 * The untracked registers are either IMPLEMENTATION DEFINED
3507 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3508 		 */
3509 		*valp = 0;
3510 	return 0;
3511 }
3512 
3513 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3514 {
3515 	int rc;
3516 	u64 val;
3517 
3518 	rc = emulate_sys_reg(sys_reg, &val);
3519 	if (!rc) {
3520 		pt_regs_write_reg(regs, rt, val);
3521 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3522 	}
3523 	return rc;
3524 }
3525 
3526 bool try_emulate_mrs(struct pt_regs *regs, u32 insn)
3527 {
3528 	u32 sys_reg, rt;
3529 
3530 	if (compat_user_mode(regs) || !aarch64_insn_is_mrs(insn))
3531 		return false;
3532 
3533 	/*
3534 	 * sys_reg values are defined as used in mrs/msr instruction.
3535 	 * shift the imm value to get the encoding.
3536 	 */
3537 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3538 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3539 	return do_emulate_mrs(regs, sys_reg, rt) == 0;
3540 }
3541 
3542 enum mitigation_state arm64_get_meltdown_state(void)
3543 {
3544 	if (__meltdown_safe)
3545 		return SPECTRE_UNAFFECTED;
3546 
3547 	if (arm64_kernel_unmapped_at_el0())
3548 		return SPECTRE_MITIGATED;
3549 
3550 	return SPECTRE_VULNERABLE;
3551 }
3552 
3553 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3554 			  char *buf)
3555 {
3556 	switch (arm64_get_meltdown_state()) {
3557 	case SPECTRE_UNAFFECTED:
3558 		return sprintf(buf, "Not affected\n");
3559 
3560 	case SPECTRE_MITIGATED:
3561 		return sprintf(buf, "Mitigation: PTI\n");
3562 
3563 	default:
3564 		return sprintf(buf, "Vulnerable\n");
3565 	}
3566 }
3567