xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision f4356947)
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(cpu_hwcaps, ARM64_NCAPS);
109 EXPORT_SYMBOL(cpu_hwcaps);
110 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
111 
112 DECLARE_BITMAP(boot_capabilities, 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, &cpu_hwcaps);
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_HIGHER_SAFE, ID_AA64ISAR2_EL1_BC_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
227 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR2_EL1_APA3_SHIFT, 4, 0),
228 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
229 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_GPA3_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_RPRES_SHIFT, 4, 0),
231 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_WFxT_SHIFT, 4, 0),
232 	ARM64_FTR_END,
233 };
234 
235 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
236 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV3_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV2_SHIFT, 4, 0),
238 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_DIT_SHIFT, 4, 0),
239 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_AMU_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_MPAM_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SEL2_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
243 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SVE_SHIFT, 4, 0),
244 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_RAS_SHIFT, 4, 0),
245 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_GIC_SHIFT, 4, 0),
246 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_AdvSIMD_SHIFT, 4, ID_AA64PFR0_EL1_AdvSIMD_NI),
247 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_FP_SHIFT, 4, ID_AA64PFR0_EL1_FP_NI),
248 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL3_SHIFT, 4, 0),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL2_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL1_SHIFT, 4, ID_AA64PFR0_EL1_ELx_64BIT_ONLY),
251 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_EL0_SHIFT, 4, ID_AA64PFR0_EL1_ELx_64BIT_ONLY),
252 	ARM64_FTR_END,
253 };
254 
255 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
256 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
257 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_SME_SHIFT, 4, 0),
258 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_MPAM_frac_SHIFT, 4, 0),
259 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_RAS_frac_SHIFT, 4, 0),
260 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
261 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_MTE_SHIFT, 4, ID_AA64PFR1_EL1_MTE_NI),
262 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_SSBS_SHIFT, 4, ID_AA64PFR1_EL1_SSBS_NI),
263 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
264 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_BT_SHIFT, 4, 0),
265 	ARM64_FTR_END,
266 };
267 
268 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
269 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
270 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_F64MM_SHIFT, 4, 0),
271 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
272 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_F32MM_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_I8MM_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SM4_SHIFT, 4, 0),
277 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
278 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SHA3_SHIFT, 4, 0),
279 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
280 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_BF16_SHIFT, 4, 0),
281 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
282 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_BitPerm_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
284 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_AES_SHIFT, 4, 0),
285 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
286 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_EL1_SVEver_SHIFT, 4, 0),
287 	ARM64_FTR_END,
288 };
289 
290 static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
291 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
292 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_FA64_SHIFT, 1, 0),
293 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
294 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SMEver_SHIFT, 4, 0),
295 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
296 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I64_SHIFT, 4, 0),
297 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
298 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, 0),
299 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
300 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I32_SHIFT, 4, 0),
301 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
302 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16B16_SHIFT, 1, 0),
303 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
304 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F16_SHIFT, 1, 0),
305 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
306 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I8I32_SHIFT, 4, 0),
307 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
308 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F32_SHIFT, 1, 0),
309 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
310 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16F32_SHIFT, 1, 0),
311 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
312 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_BI32I32_SHIFT, 1, 0),
313 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
314 		       FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F32F32_SHIFT, 1, 0),
315 	ARM64_FTR_END,
316 };
317 
318 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
319 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_ECV_SHIFT, 4, 0),
320 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_FGT_SHIFT, 4, 0),
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_EXS_SHIFT, 4, 0),
322 	/*
323 	 * Page size not being supported at Stage-2 is not fatal. You
324 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
325 	 * your favourite nesting hypervisor.
326 	 *
327 	 * There is a small corner case where the hypervisor explicitly
328 	 * advertises a given granule size at Stage-2 (value 2) on some
329 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
330 	 * vCPUs. Although this is not forbidden by the architecture, it
331 	 * indicates that the hypervisor is being silly (or buggy).
332 	 *
333 	 * We make no effort to cope with this and pretend that if these
334 	 * fields are inconsistent across vCPUs, then it isn't worth
335 	 * trying to bring KVM up.
336 	 */
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN4_2_SHIFT, 4, 1),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN64_2_SHIFT, 4, 1),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_EL1_TGRAN16_2_SHIFT, 4, 1),
340 	/*
341 	 * We already refuse to boot CPUs that don't support our configured
342 	 * page size, so we can only detect mismatches for a page size other
343 	 * than the one we're currently using. Unfortunately, SoCs like this
344 	 * exist in the wild so, even though we don't like it, we'll have to go
345 	 * along with it and treat them as non-strict.
346 	 */
347 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN4_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN4_NI),
348 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN64_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN64_NI),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_TGRAN16_SHIFT, 4, ID_AA64MMFR0_EL1_TGRAN16_NI),
350 
351 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_BIGENDEL0_SHIFT, 4, 0),
352 	/* Linux shouldn't care about secure memory */
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_SNSMEM_SHIFT, 4, 0),
354 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_BIGEND_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_ASIDBITS_SHIFT, 4, 0),
356 	/*
357 	 * Differing PARange is fine as long as all peripherals and memory are mapped
358 	 * within the minimum PARange of all CPUs
359 	 */
360 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EL1_PARANGE_SHIFT, 4, 0),
361 	ARM64_FTR_END,
362 };
363 
364 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
365 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_TIDCP1_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_AFP_SHIFT, 4, 0),
367 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_ETS_SHIFT, 4, 0),
368 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_TWED_SHIFT, 4, 0),
369 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_XNX_SHIFT, 4, 0),
370 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_EL1_SpecSEI_SHIFT, 4, 0),
371 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_PAN_SHIFT, 4, 0),
372 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_LO_SHIFT, 4, 0),
373 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_HPDS_SHIFT, 4, 0),
374 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_VH_SHIFT, 4, 0),
375 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_VMIDBits_SHIFT, 4, 0),
376 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_EL1_HAFDBS_SHIFT, 4, 0),
377 	ARM64_FTR_END,
378 };
379 
380 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
381 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_E0PD_SHIFT, 4, 0),
382 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_EVT_SHIFT, 4, 0),
383 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_BBM_SHIFT, 4, 0),
384 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_TTL_SHIFT, 4, 0),
385 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_FWB_SHIFT, 4, 0),
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_IDS_SHIFT, 4, 0),
387 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_AT_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_ST_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_NV_SHIFT, 4, 0),
390 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_CCIDX_SHIFT, 4, 0),
391 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_VARange_SHIFT, 4, 0),
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_IESB_SHIFT, 4, 0),
393 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_LSM_SHIFT, 4, 0),
394 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_UAO_SHIFT, 4, 0),
395 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EL1_CnP_SHIFT, 4, 0),
396 	ARM64_FTR_END,
397 };
398 
399 static const struct arm64_ftr_bits ftr_ctr[] = {
400 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
401 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_DIC_SHIFT, 1, 1),
402 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_IDC_SHIFT, 1, 1),
403 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_EL0_CWG_SHIFT, 4, 0),
404 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_EL0_ERG_SHIFT, 4, 0),
405 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_DminLine_SHIFT, 4, 1),
406 	/*
407 	 * Linux can handle differing I-cache policies. Userspace JITs will
408 	 * make use of *minLine.
409 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
410 	 */
411 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_EL0_L1Ip_SHIFT, 2, CTR_EL0_L1Ip_VIPT),	/* L1Ip */
412 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_EL0_IminLine_SHIFT, 4, 0),
413 	ARM64_FTR_END,
414 };
415 
416 static struct arm64_ftr_override __ro_after_init no_override = { };
417 
418 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
419 	.name		= "SYS_CTR_EL0",
420 	.ftr_bits	= ftr_ctr,
421 	.override	= &no_override,
422 };
423 
424 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
425 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_InnerShr_SHIFT, 4, 0xf),
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_FCSE_SHIFT, 4, 0),
427 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_AuxReg_SHIFT, 4, 0),
428 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_TCM_SHIFT, 4, 0),
429 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_ShareLvl_SHIFT, 4, 0),
430 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_OuterShr_SHIFT, 4, 0xf),
431 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_PMSA_SHIFT, 4, 0),
432 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_EL1_VMSA_SHIFT, 4, 0),
433 	ARM64_FTR_END,
434 };
435 
436 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
437 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_DoubleLock_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_PMSVer_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_CTX_CMPs_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_WRPs_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_BRPs_SHIFT, 4, 0),
442 	/*
443 	 * We can instantiate multiple PMU instances with different levels
444 	 * of support.
445 	 */
446 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_EL1_PMUVer_SHIFT, 4, 0),
447 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_EL1_DebugVer_SHIFT, 4, 0x6),
448 	ARM64_FTR_END,
449 };
450 
451 static const struct arm64_ftr_bits ftr_mvfr0[] = {
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPRound_SHIFT, 4, 0),
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPShVec_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPSqrt_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPDivide_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPTrap_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPDP_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_FPSP_SHIFT, 4, 0),
459 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR0_EL1_SIMDReg_SHIFT, 4, 0),
460 	ARM64_FTR_END,
461 };
462 
463 static const struct arm64_ftr_bits ftr_mvfr1[] = {
464 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDFMAC_SHIFT, 4, 0),
465 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPHP_SHIFT, 4, 0),
466 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDHP_SHIFT, 4, 0),
467 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDSP_SHIFT, 4, 0),
468 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDInt_SHIFT, 4, 0),
469 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDLS_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPDNaN_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPFtZ_SHIFT, 4, 0),
472 	ARM64_FTR_END,
473 };
474 
475 static const struct arm64_ftr_bits ftr_mvfr2[] = {
476 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_EL1_FPMisc_SHIFT, 4, 0),
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_EL1_SIMDMisc_SHIFT, 4, 0),
478 	ARM64_FTR_END,
479 };
480 
481 static const struct arm64_ftr_bits ftr_dczid[] = {
482 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_EL0_DZP_SHIFT, 1, 1),
483 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_EL0_BS_SHIFT, 4, 0),
484 	ARM64_FTR_END,
485 };
486 
487 static const struct arm64_ftr_bits ftr_gmid[] = {
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, GMID_EL1_BS_SHIFT, 4, 0),
489 	ARM64_FTR_END,
490 };
491 
492 static const struct arm64_ftr_bits ftr_id_isar0[] = {
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Divide_SHIFT, 4, 0),
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Debug_SHIFT, 4, 0),
495 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Coproc_SHIFT, 4, 0),
496 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_CmpBranch_SHIFT, 4, 0),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_BitField_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_BitCount_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_EL1_Swap_SHIFT, 4, 0),
500 	ARM64_FTR_END,
501 };
502 
503 static const struct arm64_ftr_bits ftr_id_isar5[] = {
504 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_RDM_SHIFT, 4, 0),
505 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_CRC32_SHIFT, 4, 0),
506 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SHA2_SHIFT, 4, 0),
507 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SHA1_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_AES_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_EL1_SEVL_SHIFT, 4, 0),
510 	ARM64_FTR_END,
511 };
512 
513 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_EVT_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_CCIDX_SHIFT, 4, 0),
516 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_LSM_SHIFT, 4, 0),
517 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_HPDS_SHIFT, 4, 0),
518 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_CnP_SHIFT, 4, 0),
519 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_XNX_SHIFT, 4, 0),
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EL1_AC2_SHIFT, 4, 0),
521 
522 	/*
523 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
524 	 * external abort on speculative read. It is safe to assume that an
525 	 * SError might be generated than it will not be. Hence it has been
526 	 * classified as FTR_HIGHER_SAFE.
527 	 */
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_EL1_SpecSEI_SHIFT, 4, 0),
529 	ARM64_FTR_END,
530 };
531 
532 static const struct arm64_ftr_bits ftr_id_isar4[] = {
533 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SWP_frac_SHIFT, 4, 0),
534 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_PSR_M_SHIFT, 4, 0),
535 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SynchPrim_frac_SHIFT, 4, 0),
536 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Barrier_SHIFT, 4, 0),
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_SMC_SHIFT, 4, 0),
538 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Writeback_SHIFT, 4, 0),
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_WithShifts_SHIFT, 4, 0),
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_EL1_Unpriv_SHIFT, 4, 0),
541 	ARM64_FTR_END,
542 };
543 
544 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
545 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_EL1_ETS_SHIFT, 4, 0),
546 	ARM64_FTR_END,
547 };
548 
549 static const struct arm64_ftr_bits ftr_id_isar6[] = {
550 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_I8MM_SHIFT, 4, 0),
551 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_BF16_SHIFT, 4, 0),
552 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_SPECRES_SHIFT, 4, 0),
553 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_SB_SHIFT, 4, 0),
554 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_FHM_SHIFT, 4, 0),
555 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_DP_SHIFT, 4, 0),
556 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_EL1_JSCVT_SHIFT, 4, 0),
557 	ARM64_FTR_END,
558 };
559 
560 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
561 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_DIT_SHIFT, 4, 0),
562 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_CSV2_SHIFT, 4, 0),
563 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State3_SHIFT, 4, 0),
564 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State2_SHIFT, 4, 0),
565 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State1_SHIFT, 4, 0),
566 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_EL1_State0_SHIFT, 4, 0),
567 	ARM64_FTR_END,
568 };
569 
570 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
571 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_GIC_SHIFT, 4, 0),
572 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Virt_frac_SHIFT, 4, 0),
573 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Sec_frac_SHIFT, 4, 0),
574 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_GenTimer_SHIFT, 4, 0),
575 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Virtualization_SHIFT, 4, 0),
576 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_MProgMod_SHIFT, 4, 0),
577 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_Security_SHIFT, 4, 0),
578 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_EL1_ProgMod_SHIFT, 4, 0),
579 	ARM64_FTR_END,
580 };
581 
582 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
583 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_EL1_SSBS_SHIFT, 4, 0),
584 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_EL1_CSV3_SHIFT, 4, 0),
585 	ARM64_FTR_END,
586 };
587 
588 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
589 	/* [31:28] TraceFilt */
590 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_DFR0_EL1_PerfMon_SHIFT, 4, 0),
591 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MProfDbg_SHIFT, 4, 0),
592 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MMapTrc_SHIFT, 4, 0),
593 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopTrc_SHIFT, 4, 0),
594 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MMapDbg_SHIFT, 4, 0),
595 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopSDbg_SHIFT, 4, 0),
596 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_CopDbg_SHIFT, 4, 0),
597 	ARM64_FTR_END,
598 };
599 
600 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
601 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_EL1_MTPMU_SHIFT, 4, 0),
602 	ARM64_FTR_END,
603 };
604 
605 static const struct arm64_ftr_bits ftr_zcr[] = {
606 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
607 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_WIDTH, 0),	/* LEN */
608 	ARM64_FTR_END,
609 };
610 
611 static const struct arm64_ftr_bits ftr_smcr[] = {
612 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
613 		SMCR_ELx_LEN_SHIFT, SMCR_ELx_LEN_WIDTH, 0),	/* LEN */
614 	ARM64_FTR_END,
615 };
616 
617 /*
618  * Common ftr bits for a 32bit register with all hidden, strict
619  * attributes, with 4bit feature fields and a default safe value of
620  * 0. Covers the following 32bit registers:
621  * id_isar[1-3], id_mmfr[1-3]
622  */
623 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
624 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
625 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
626 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
627 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
628 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
629 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
630 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
631 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
632 	ARM64_FTR_END,
633 };
634 
635 /* Table for a single 32bit feature value */
636 static const struct arm64_ftr_bits ftr_single32[] = {
637 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
638 	ARM64_FTR_END,
639 };
640 
641 static const struct arm64_ftr_bits ftr_raz[] = {
642 	ARM64_FTR_END,
643 };
644 
645 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
646 		.sys_id = id,					\
647 		.reg = 	&(struct arm64_ftr_reg){		\
648 			.name = id_str,				\
649 			.override = (ovr),			\
650 			.ftr_bits = &((table)[0]),		\
651 	}}
652 
653 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
654 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
655 
656 #define ARM64_FTR_REG(id, table)		\
657 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
658 
659 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
660 struct arm64_ftr_override __ro_after_init id_aa64pfr0_override;
661 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
662 struct arm64_ftr_override __ro_after_init id_aa64zfr0_override;
663 struct arm64_ftr_override __ro_after_init id_aa64smfr0_override;
664 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
665 struct arm64_ftr_override __ro_after_init id_aa64isar2_override;
666 
667 static const struct __ftr_reg_entry {
668 	u32			sys_id;
669 	struct arm64_ftr_reg 	*reg;
670 } arm64_ftr_regs[] = {
671 
672 	/* Op1 = 0, CRn = 0, CRm = 1 */
673 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
674 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
675 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
676 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
677 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
678 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
679 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
680 
681 	/* Op1 = 0, CRn = 0, CRm = 2 */
682 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
683 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
684 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
685 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
686 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
687 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
688 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
689 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
690 
691 	/* Op1 = 0, CRn = 0, CRm = 3 */
692 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_mvfr0),
693 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_mvfr1),
694 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
695 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
696 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
697 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
698 
699 	/* Op1 = 0, CRn = 0, CRm = 4 */
700 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0,
701 			       &id_aa64pfr0_override),
702 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
703 			       &id_aa64pfr1_override),
704 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0,
705 			       &id_aa64zfr0_override),
706 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64SMFR0_EL1, ftr_id_aa64smfr0,
707 			       &id_aa64smfr0_override),
708 
709 	/* Op1 = 0, CRn = 0, CRm = 5 */
710 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
711 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
712 
713 	/* Op1 = 0, CRn = 0, CRm = 6 */
714 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
715 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
716 			       &id_aa64isar1_override),
717 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2,
718 			       &id_aa64isar2_override),
719 
720 	/* Op1 = 0, CRn = 0, CRm = 7 */
721 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
722 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
723 			       &id_aa64mmfr1_override),
724 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
725 
726 	/* Op1 = 0, CRn = 1, CRm = 2 */
727 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
728 	ARM64_FTR_REG(SYS_SMCR_EL1, ftr_smcr),
729 
730 	/* Op1 = 1, CRn = 0, CRm = 0 */
731 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
732 
733 	/* Op1 = 3, CRn = 0, CRm = 0 */
734 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
735 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
736 
737 	/* Op1 = 3, CRn = 14, CRm = 0 */
738 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
739 };
740 
741 static int search_cmp_ftr_reg(const void *id, const void *regp)
742 {
743 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
744 }
745 
746 /*
747  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
748  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
749  * ascending order of sys_id, we use binary search to find a matching
750  * entry.
751  *
752  * returns - Upon success,  matching ftr_reg entry for id.
753  *         - NULL on failure. It is upto the caller to decide
754  *	     the impact of a failure.
755  */
756 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
757 {
758 	const struct __ftr_reg_entry *ret;
759 
760 	ret = bsearch((const void *)(unsigned long)sys_id,
761 			arm64_ftr_regs,
762 			ARRAY_SIZE(arm64_ftr_regs),
763 			sizeof(arm64_ftr_regs[0]),
764 			search_cmp_ftr_reg);
765 	if (ret)
766 		return ret->reg;
767 	return NULL;
768 }
769 
770 /*
771  * get_arm64_ftr_reg - Looks up a feature register entry using
772  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
773  *
774  * returns - Upon success,  matching ftr_reg entry for id.
775  *         - NULL on failure but with an WARN_ON().
776  */
777 struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
778 {
779 	struct arm64_ftr_reg *reg;
780 
781 	reg = get_arm64_ftr_reg_nowarn(sys_id);
782 
783 	/*
784 	 * Requesting a non-existent register search is an error. Warn
785 	 * and let the caller handle it.
786 	 */
787 	WARN_ON(!reg);
788 	return reg;
789 }
790 
791 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
792 			       s64 ftr_val)
793 {
794 	u64 mask = arm64_ftr_mask(ftrp);
795 
796 	reg &= ~mask;
797 	reg |= (ftr_val << ftrp->shift) & mask;
798 	return reg;
799 }
800 
801 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
802 				s64 cur)
803 {
804 	s64 ret = 0;
805 
806 	switch (ftrp->type) {
807 	case FTR_EXACT:
808 		ret = ftrp->safe_val;
809 		break;
810 	case FTR_LOWER_SAFE:
811 		ret = min(new, cur);
812 		break;
813 	case FTR_HIGHER_OR_ZERO_SAFE:
814 		if (!cur || !new)
815 			break;
816 		fallthrough;
817 	case FTR_HIGHER_SAFE:
818 		ret = max(new, cur);
819 		break;
820 	default:
821 		BUG();
822 	}
823 
824 	return ret;
825 }
826 
827 static void __init sort_ftr_regs(void)
828 {
829 	unsigned int i;
830 
831 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
832 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
833 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
834 		unsigned int j = 0;
835 
836 		/*
837 		 * Features here must be sorted in descending order with respect
838 		 * to their shift values and should not overlap with each other.
839 		 */
840 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
841 			unsigned int width = ftr_reg->ftr_bits[j].width;
842 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
843 			unsigned int prev_shift;
844 
845 			WARN((shift  + width) > 64,
846 				"%s has invalid feature at shift %d\n",
847 				ftr_reg->name, shift);
848 
849 			/*
850 			 * Skip the first feature. There is nothing to
851 			 * compare against for now.
852 			 */
853 			if (j == 0)
854 				continue;
855 
856 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
857 			WARN((shift + width) > prev_shift,
858 				"%s has feature overlap at shift %d\n",
859 				ftr_reg->name, shift);
860 		}
861 
862 		/*
863 		 * Skip the first register. There is nothing to
864 		 * compare against for now.
865 		 */
866 		if (i == 0)
867 			continue;
868 		/*
869 		 * Registers here must be sorted in ascending order with respect
870 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
871 		 * to work correctly.
872 		 */
873 		BUG_ON(arm64_ftr_regs[i].sys_id <= arm64_ftr_regs[i - 1].sys_id);
874 	}
875 }
876 
877 /*
878  * Initialise the CPU feature register from Boot CPU values.
879  * Also initiliases the strict_mask for the register.
880  * Any bits that are not covered by an arm64_ftr_bits entry are considered
881  * RES0 for the system-wide value, and must strictly match.
882  */
883 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
884 {
885 	u64 val = 0;
886 	u64 strict_mask = ~0x0ULL;
887 	u64 user_mask = 0;
888 	u64 valid_mask = 0;
889 
890 	const struct arm64_ftr_bits *ftrp;
891 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
892 
893 	if (!reg)
894 		return;
895 
896 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
897 		u64 ftr_mask = arm64_ftr_mask(ftrp);
898 		s64 ftr_new = arm64_ftr_value(ftrp, new);
899 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
900 
901 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
902 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
903 			char *str = NULL;
904 
905 			if (ftr_ovr != tmp) {
906 				/* Unsafe, remove the override */
907 				reg->override->mask &= ~ftr_mask;
908 				reg->override->val &= ~ftr_mask;
909 				tmp = ftr_ovr;
910 				str = "ignoring override";
911 			} else if (ftr_new != tmp) {
912 				/* Override was valid */
913 				ftr_new = tmp;
914 				str = "forced";
915 			} else if (ftr_ovr == tmp) {
916 				/* Override was the safe value */
917 				str = "already set";
918 			}
919 
920 			if (str)
921 				pr_warn("%s[%d:%d]: %s to %llx\n",
922 					reg->name,
923 					ftrp->shift + ftrp->width - 1,
924 					ftrp->shift, str, tmp);
925 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
926 			reg->override->val &= ~ftr_mask;
927 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
928 				reg->name,
929 				ftrp->shift + ftrp->width - 1,
930 				ftrp->shift);
931 		}
932 
933 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
934 
935 		valid_mask |= ftr_mask;
936 		if (!ftrp->strict)
937 			strict_mask &= ~ftr_mask;
938 		if (ftrp->visible)
939 			user_mask |= ftr_mask;
940 		else
941 			reg->user_val = arm64_ftr_set_value(ftrp,
942 							    reg->user_val,
943 							    ftrp->safe_val);
944 	}
945 
946 	val &= valid_mask;
947 
948 	reg->sys_val = val;
949 	reg->strict_mask = strict_mask;
950 	reg->user_mask = user_mask;
951 }
952 
953 extern const struct arm64_cpu_capabilities arm64_errata[];
954 static const struct arm64_cpu_capabilities arm64_features[];
955 
956 static void __init
957 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
958 {
959 	for (; caps->matches; caps++) {
960 		if (WARN(caps->capability >= ARM64_NCAPS,
961 			"Invalid capability %d\n", caps->capability))
962 			continue;
963 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
964 			"Duplicate entry for capability %d\n",
965 			caps->capability))
966 			continue;
967 		cpu_hwcaps_ptrs[caps->capability] = caps;
968 	}
969 }
970 
971 static void __init init_cpu_hwcaps_indirect_list(void)
972 {
973 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
974 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
975 }
976 
977 static void __init setup_boot_cpu_capabilities(void);
978 
979 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
980 {
981 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
982 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
983 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
984 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
985 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
986 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
987 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
988 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
989 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
990 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
991 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
992 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
993 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
994 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
995 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
996 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
997 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
998 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
999 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
1000 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
1001 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
1002 }
1003 
1004 void __init init_cpu_features(struct cpuinfo_arm64 *info)
1005 {
1006 	/* Before we start using the tables, make sure it is sorted */
1007 	sort_ftr_regs();
1008 
1009 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
1010 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
1011 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
1012 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
1013 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
1014 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
1015 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
1016 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
1017 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
1018 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
1019 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
1020 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
1021 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
1022 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
1023 	init_cpu_ftr_reg(SYS_ID_AA64SMFR0_EL1, info->reg_id_aa64smfr0);
1024 
1025 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
1026 		init_32bit_cpu_features(&info->aarch32);
1027 
1028 	if (IS_ENABLED(CONFIG_ARM64_SVE) &&
1029 	    id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1))) {
1030 		info->reg_zcr = read_zcr_features();
1031 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
1032 		vec_init_vq_map(ARM64_VEC_SVE);
1033 	}
1034 
1035 	if (IS_ENABLED(CONFIG_ARM64_SME) &&
1036 	    id_aa64pfr1_sme(read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1))) {
1037 		info->reg_smcr = read_smcr_features();
1038 		/*
1039 		 * We mask out SMPS since even if the hardware
1040 		 * supports priorities the kernel does not at present
1041 		 * and we block access to them.
1042 		 */
1043 		info->reg_smidr = read_cpuid(SMIDR_EL1) & ~SMIDR_EL1_SMPS;
1044 		init_cpu_ftr_reg(SYS_SMCR_EL1, info->reg_smcr);
1045 		vec_init_vq_map(ARM64_VEC_SME);
1046 	}
1047 
1048 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
1049 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
1050 
1051 	/*
1052 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
1053 	 * before we handle the boot CPU below.
1054 	 */
1055 	init_cpu_hwcaps_indirect_list();
1056 
1057 	/*
1058 	 * Detect and enable early CPU capabilities based on the boot CPU,
1059 	 * after we have initialised the CPU feature infrastructure.
1060 	 */
1061 	setup_boot_cpu_capabilities();
1062 }
1063 
1064 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
1065 {
1066 	const struct arm64_ftr_bits *ftrp;
1067 
1068 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
1069 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
1070 		s64 ftr_new = arm64_ftr_value(ftrp, new);
1071 
1072 		if (ftr_cur == ftr_new)
1073 			continue;
1074 		/* Find a safe value */
1075 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
1076 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
1077 	}
1078 
1079 }
1080 
1081 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
1082 {
1083 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1084 
1085 	if (!regp)
1086 		return 0;
1087 
1088 	update_cpu_ftr_reg(regp, val);
1089 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
1090 		return 0;
1091 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
1092 			regp->name, boot, cpu, val);
1093 	return 1;
1094 }
1095 
1096 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1097 {
1098 	const struct arm64_ftr_bits *ftrp;
1099 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1100 
1101 	if (!regp)
1102 		return;
1103 
1104 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1105 		if (ftrp->shift == field) {
1106 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1107 			break;
1108 		}
1109 	}
1110 
1111 	/* Bogus field? */
1112 	WARN_ON(!ftrp->width);
1113 }
1114 
1115 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1116 					 struct cpuinfo_arm64 *boot)
1117 {
1118 	static bool boot_cpu_32bit_regs_overridden = false;
1119 
1120 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1121 		return;
1122 
1123 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1124 		return;
1125 
1126 	boot->aarch32 = info->aarch32;
1127 	init_32bit_cpu_features(&boot->aarch32);
1128 	boot_cpu_32bit_regs_overridden = true;
1129 }
1130 
1131 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1132 				     struct cpuinfo_32bit *boot)
1133 {
1134 	int taint = 0;
1135 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1136 
1137 	/*
1138 	 * If we don't have AArch32 at EL1, then relax the strictness of
1139 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1140 	 */
1141 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1142 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_EL1_SMC_SHIFT);
1143 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Virt_frac_SHIFT);
1144 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Sec_frac_SHIFT);
1145 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Virtualization_SHIFT);
1146 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_Security_SHIFT);
1147 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_EL1_ProgMod_SHIFT);
1148 	}
1149 
1150 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1151 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1152 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1153 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1154 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1155 				      info->reg_id_isar0, boot->reg_id_isar0);
1156 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1157 				      info->reg_id_isar1, boot->reg_id_isar1);
1158 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1159 				      info->reg_id_isar2, boot->reg_id_isar2);
1160 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1161 				      info->reg_id_isar3, boot->reg_id_isar3);
1162 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1163 				      info->reg_id_isar4, boot->reg_id_isar4);
1164 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1165 				      info->reg_id_isar5, boot->reg_id_isar5);
1166 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1167 				      info->reg_id_isar6, boot->reg_id_isar6);
1168 
1169 	/*
1170 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1171 	 * ACTLR formats could differ across CPUs and therefore would have to
1172 	 * be trapped for virtualization anyway.
1173 	 */
1174 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1175 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1176 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1177 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1178 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1179 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1180 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1181 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1182 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1183 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1184 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1185 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1186 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1187 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1188 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1189 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1190 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1191 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1192 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1193 				      info->reg_mvfr0, boot->reg_mvfr0);
1194 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1195 				      info->reg_mvfr1, boot->reg_mvfr1);
1196 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1197 				      info->reg_mvfr2, boot->reg_mvfr2);
1198 
1199 	return taint;
1200 }
1201 
1202 /*
1203  * Update system wide CPU feature registers with the values from a
1204  * non-boot CPU. Also performs SANITY checks to make sure that there
1205  * aren't any insane variations from that of the boot CPU.
1206  */
1207 void update_cpu_features(int cpu,
1208 			 struct cpuinfo_arm64 *info,
1209 			 struct cpuinfo_arm64 *boot)
1210 {
1211 	int taint = 0;
1212 
1213 	/*
1214 	 * The kernel can handle differing I-cache policies, but otherwise
1215 	 * caches should look identical. Userspace JITs will make use of
1216 	 * *minLine.
1217 	 */
1218 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1219 				      info->reg_ctr, boot->reg_ctr);
1220 
1221 	/*
1222 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1223 	 * could result in too much or too little memory being zeroed if a
1224 	 * process is preempted and migrated between CPUs.
1225 	 */
1226 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1227 				      info->reg_dczid, boot->reg_dczid);
1228 
1229 	/* If different, timekeeping will be broken (especially with KVM) */
1230 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1231 				      info->reg_cntfrq, boot->reg_cntfrq);
1232 
1233 	/*
1234 	 * The kernel uses self-hosted debug features and expects CPUs to
1235 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1236 	 * and BRPs to be identical.
1237 	 * ID_AA64DFR1 is currently RES0.
1238 	 */
1239 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1240 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1241 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1242 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1243 	/*
1244 	 * Even in big.LITTLE, processors should be identical instruction-set
1245 	 * wise.
1246 	 */
1247 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1248 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1249 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1250 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1251 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1252 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1253 
1254 	/*
1255 	 * Differing PARange support is fine as long as all peripherals and
1256 	 * memory are mapped within the minimum PARange of all CPUs.
1257 	 * Linux should not care about secure memory.
1258 	 */
1259 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1260 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1261 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1262 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1263 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1264 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1265 
1266 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1267 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1268 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1269 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1270 
1271 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1272 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1273 
1274 	taint |= check_update_ftr_reg(SYS_ID_AA64SMFR0_EL1, cpu,
1275 				      info->reg_id_aa64smfr0, boot->reg_id_aa64smfr0);
1276 
1277 	if (IS_ENABLED(CONFIG_ARM64_SVE) &&
1278 	    id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1))) {
1279 		info->reg_zcr = read_zcr_features();
1280 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1281 					info->reg_zcr, boot->reg_zcr);
1282 
1283 		/* Probe vector lengths */
1284 		if (!system_capabilities_finalized())
1285 			vec_update_vq_map(ARM64_VEC_SVE);
1286 	}
1287 
1288 	if (IS_ENABLED(CONFIG_ARM64_SME) &&
1289 	    id_aa64pfr1_sme(read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1))) {
1290 		info->reg_smcr = read_smcr_features();
1291 		/*
1292 		 * We mask out SMPS since even if the hardware
1293 		 * supports priorities the kernel does not at present
1294 		 * and we block access to them.
1295 		 */
1296 		info->reg_smidr = read_cpuid(SMIDR_EL1) & ~SMIDR_EL1_SMPS;
1297 		taint |= check_update_ftr_reg(SYS_SMCR_EL1, cpu,
1298 					info->reg_smcr, boot->reg_smcr);
1299 
1300 		/* Probe vector lengths */
1301 		if (!system_capabilities_finalized())
1302 			vec_update_vq_map(ARM64_VEC_SME);
1303 	}
1304 
1305 	/*
1306 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1307 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1308 	 * value is the same on all CPUs.
1309 	 */
1310 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1311 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1312 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1313 					      info->reg_gmid, boot->reg_gmid);
1314 	}
1315 
1316 	/*
1317 	 * If we don't have AArch32 at all then skip the checks entirely
1318 	 * as the register values may be UNKNOWN and we're not going to be
1319 	 * using them for anything.
1320 	 *
1321 	 * This relies on a sanitised view of the AArch64 ID registers
1322 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1323 	 */
1324 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1325 		lazy_init_32bit_cpu_features(info, boot);
1326 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1327 						   &boot->aarch32);
1328 	}
1329 
1330 	/*
1331 	 * Mismatched CPU features are a recipe for disaster. Don't even
1332 	 * pretend to support them.
1333 	 */
1334 	if (taint) {
1335 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1336 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1337 	}
1338 }
1339 
1340 u64 read_sanitised_ftr_reg(u32 id)
1341 {
1342 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1343 
1344 	if (!regp)
1345 		return 0;
1346 	return regp->sys_val;
1347 }
1348 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1349 
1350 #define read_sysreg_case(r)	\
1351 	case r:		val = read_sysreg_s(r); break;
1352 
1353 /*
1354  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1355  * Read the system register on the current CPU
1356  */
1357 u64 __read_sysreg_by_encoding(u32 sys_id)
1358 {
1359 	struct arm64_ftr_reg *regp;
1360 	u64 val;
1361 
1362 	switch (sys_id) {
1363 	read_sysreg_case(SYS_ID_PFR0_EL1);
1364 	read_sysreg_case(SYS_ID_PFR1_EL1);
1365 	read_sysreg_case(SYS_ID_PFR2_EL1);
1366 	read_sysreg_case(SYS_ID_DFR0_EL1);
1367 	read_sysreg_case(SYS_ID_DFR1_EL1);
1368 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1369 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1370 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1371 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1372 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1373 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1374 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1375 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1376 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1377 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1378 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1379 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1380 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1381 	read_sysreg_case(SYS_MVFR0_EL1);
1382 	read_sysreg_case(SYS_MVFR1_EL1);
1383 	read_sysreg_case(SYS_MVFR2_EL1);
1384 
1385 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1386 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1387 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1388 	read_sysreg_case(SYS_ID_AA64SMFR0_EL1);
1389 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1390 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1391 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1392 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1393 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1394 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1395 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1396 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1397 
1398 	read_sysreg_case(SYS_CNTFRQ_EL0);
1399 	read_sysreg_case(SYS_CTR_EL0);
1400 	read_sysreg_case(SYS_DCZID_EL0);
1401 
1402 	default:
1403 		BUG();
1404 		return 0;
1405 	}
1406 
1407 	regp  = get_arm64_ftr_reg(sys_id);
1408 	if (regp) {
1409 		val &= ~regp->override->mask;
1410 		val |= (regp->override->val & regp->override->mask);
1411 	}
1412 
1413 	return val;
1414 }
1415 
1416 #include <linux/irqchip/arm-gic-v3.h>
1417 
1418 static bool
1419 has_always(const struct arm64_cpu_capabilities *entry, int scope)
1420 {
1421 	return true;
1422 }
1423 
1424 static bool
1425 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1426 {
1427 	int val = cpuid_feature_extract_field_width(reg, entry->field_pos,
1428 						    entry->field_width,
1429 						    entry->sign);
1430 
1431 	return val >= entry->min_field_value;
1432 }
1433 
1434 static u64
1435 read_scoped_sysreg(const struct arm64_cpu_capabilities *entry, int scope)
1436 {
1437 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1438 	if (scope == SCOPE_SYSTEM)
1439 		return read_sanitised_ftr_reg(entry->sys_reg);
1440 	else
1441 		return __read_sysreg_by_encoding(entry->sys_reg);
1442 }
1443 
1444 static bool
1445 has_user_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1446 {
1447 	int mask;
1448 	struct arm64_ftr_reg *regp;
1449 	u64 val = read_scoped_sysreg(entry, scope);
1450 
1451 	regp = get_arm64_ftr_reg(entry->sys_reg);
1452 	if (!regp)
1453 		return false;
1454 
1455 	mask = cpuid_feature_extract_unsigned_field_width(regp->user_mask,
1456 							  entry->field_pos,
1457 							  entry->field_width);
1458 	if (!mask)
1459 		return false;
1460 
1461 	return feature_matches(val, entry);
1462 }
1463 
1464 static bool
1465 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1466 {
1467 	u64 val = read_scoped_sysreg(entry, scope);
1468 	return feature_matches(val, entry);
1469 }
1470 
1471 const struct cpumask *system_32bit_el0_cpumask(void)
1472 {
1473 	if (!system_supports_32bit_el0())
1474 		return cpu_none_mask;
1475 
1476 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1477 		return cpu_32bit_el0_mask;
1478 
1479 	return cpu_possible_mask;
1480 }
1481 
1482 static int __init parse_32bit_el0_param(char *str)
1483 {
1484 	allow_mismatched_32bit_el0 = true;
1485 	return 0;
1486 }
1487 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1488 
1489 static ssize_t aarch32_el0_show(struct device *dev,
1490 				struct device_attribute *attr, char *buf)
1491 {
1492 	const struct cpumask *mask = system_32bit_el0_cpumask();
1493 
1494 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1495 }
1496 static const DEVICE_ATTR_RO(aarch32_el0);
1497 
1498 static int __init aarch32_el0_sysfs_init(void)
1499 {
1500 	struct device *dev_root;
1501 	int ret = 0;
1502 
1503 	if (!allow_mismatched_32bit_el0)
1504 		return 0;
1505 
1506 	dev_root = bus_get_dev_root(&cpu_subsys);
1507 	if (dev_root) {
1508 		ret = device_create_file(dev_root, &dev_attr_aarch32_el0);
1509 		put_device(dev_root);
1510 	}
1511 	return ret;
1512 }
1513 device_initcall(aarch32_el0_sysfs_init);
1514 
1515 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1516 {
1517 	if (!has_cpuid_feature(entry, scope))
1518 		return allow_mismatched_32bit_el0;
1519 
1520 	if (scope == SCOPE_SYSTEM)
1521 		pr_info("detected: 32-bit EL0 Support\n");
1522 
1523 	return true;
1524 }
1525 
1526 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1527 {
1528 	bool has_sre;
1529 
1530 	if (!has_cpuid_feature(entry, scope))
1531 		return false;
1532 
1533 	has_sre = gic_enable_sre();
1534 	if (!has_sre)
1535 		pr_warn_once("%s present but disabled by higher exception level\n",
1536 			     entry->desc);
1537 
1538 	return has_sre;
1539 }
1540 
1541 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1542 {
1543 	u32 midr = read_cpuid_id();
1544 
1545 	/* Cavium ThunderX pass 1.x and 2.x */
1546 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1547 		MIDR_CPU_VAR_REV(0, 0),
1548 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1549 }
1550 
1551 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1552 {
1553 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1554 
1555 	return cpuid_feature_extract_signed_field(pfr0,
1556 					ID_AA64PFR0_EL1_FP_SHIFT) < 0;
1557 }
1558 
1559 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1560 			  int scope)
1561 {
1562 	u64 ctr;
1563 
1564 	if (scope == SCOPE_SYSTEM)
1565 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1566 	else
1567 		ctr = read_cpuid_effective_cachetype();
1568 
1569 	return ctr & BIT(CTR_EL0_IDC_SHIFT);
1570 }
1571 
1572 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1573 {
1574 	/*
1575 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1576 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1577 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1578 	 * value.
1579 	 */
1580 	if (!(read_cpuid_cachetype() & BIT(CTR_EL0_IDC_SHIFT)))
1581 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1582 }
1583 
1584 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1585 			  int scope)
1586 {
1587 	u64 ctr;
1588 
1589 	if (scope == SCOPE_SYSTEM)
1590 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1591 	else
1592 		ctr = read_cpuid_cachetype();
1593 
1594 	return ctr & BIT(CTR_EL0_DIC_SHIFT);
1595 }
1596 
1597 static bool __maybe_unused
1598 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1599 {
1600 	/*
1601 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1602 	 * may share TLB entries with a CPU stuck in the crashed
1603 	 * kernel.
1604 	 */
1605 	if (is_kdump_kernel())
1606 		return false;
1607 
1608 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1609 		return false;
1610 
1611 	return has_cpuid_feature(entry, scope);
1612 }
1613 
1614 /*
1615  * This check is triggered during the early boot before the cpufeature
1616  * is initialised. Checking the status on the local CPU allows the boot
1617  * CPU to detect the need for non-global mappings and thus avoiding a
1618  * pagetable re-write after all the CPUs are booted. This check will be
1619  * anyway run on individual CPUs, allowing us to get the consistent
1620  * state once the SMP CPUs are up and thus make the switch to non-global
1621  * mappings if required.
1622  */
1623 bool kaslr_requires_kpti(void)
1624 {
1625 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1626 		return false;
1627 
1628 	/*
1629 	 * E0PD does a similar job to KPTI so can be used instead
1630 	 * where available.
1631 	 */
1632 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1633 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1634 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1635 						ID_AA64MMFR2_EL1_E0PD_SHIFT))
1636 			return false;
1637 	}
1638 
1639 	/*
1640 	 * Systems affected by Cavium erratum 24756 are incompatible
1641 	 * with KPTI.
1642 	 */
1643 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1644 		extern const struct midr_range cavium_erratum_27456_cpus[];
1645 
1646 		if (is_midr_in_range_list(read_cpuid_id(),
1647 					  cavium_erratum_27456_cpus))
1648 			return false;
1649 	}
1650 
1651 	return kaslr_enabled();
1652 }
1653 
1654 static bool __meltdown_safe = true;
1655 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1656 
1657 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1658 				int scope)
1659 {
1660 	/* List of CPUs that are not vulnerable and don't need KPTI */
1661 	static const struct midr_range kpti_safe_list[] = {
1662 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1663 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1664 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1665 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1666 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1667 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1668 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1669 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1670 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1671 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1672 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1673 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1674 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1675 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1676 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1677 		{ /* sentinel */ }
1678 	};
1679 	char const *str = "kpti command line option";
1680 	bool meltdown_safe;
1681 
1682 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1683 
1684 	/* Defer to CPU feature registers */
1685 	if (has_cpuid_feature(entry, scope))
1686 		meltdown_safe = true;
1687 
1688 	if (!meltdown_safe)
1689 		__meltdown_safe = false;
1690 
1691 	/*
1692 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1693 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1694 	 * ends as well as you might imagine. Don't even try. We cannot rely
1695 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1696 	 * because cpucap detection order may change. However, since we know
1697 	 * affected CPUs are always in a homogeneous configuration, it is
1698 	 * safe to rely on this_cpu_has_cap() here.
1699 	 */
1700 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1701 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1702 		__kpti_forced = -1;
1703 	}
1704 
1705 	/* Useful for KASLR robustness */
1706 	if (kaslr_requires_kpti()) {
1707 		if (!__kpti_forced) {
1708 			str = "KASLR";
1709 			__kpti_forced = 1;
1710 		}
1711 	}
1712 
1713 	if (cpu_mitigations_off() && !__kpti_forced) {
1714 		str = "mitigations=off";
1715 		__kpti_forced = -1;
1716 	}
1717 
1718 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1719 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1720 		return false;
1721 	}
1722 
1723 	/* Forced? */
1724 	if (__kpti_forced) {
1725 		pr_info_once("kernel page table isolation forced %s by %s\n",
1726 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1727 		return __kpti_forced > 0;
1728 	}
1729 
1730 	return !meltdown_safe;
1731 }
1732 
1733 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1734 #define KPTI_NG_TEMP_VA		(-(1UL << PMD_SHIFT))
1735 
1736 extern
1737 void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt,
1738 			     phys_addr_t size, pgprot_t prot,
1739 			     phys_addr_t (*pgtable_alloc)(int), int flags);
1740 
1741 static phys_addr_t kpti_ng_temp_alloc;
1742 
1743 static phys_addr_t kpti_ng_pgd_alloc(int shift)
1744 {
1745 	kpti_ng_temp_alloc -= PAGE_SIZE;
1746 	return kpti_ng_temp_alloc;
1747 }
1748 
1749 static void
1750 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1751 {
1752 	typedef void (kpti_remap_fn)(int, int, phys_addr_t, unsigned long);
1753 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1754 	kpti_remap_fn *remap_fn;
1755 
1756 	int cpu = smp_processor_id();
1757 	int levels = CONFIG_PGTABLE_LEVELS;
1758 	int order = order_base_2(levels);
1759 	u64 kpti_ng_temp_pgd_pa = 0;
1760 	pgd_t *kpti_ng_temp_pgd;
1761 	u64 alloc = 0;
1762 
1763 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1764 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1765 
1766 		__this_cpu_write(this_cpu_vector, v);
1767 	}
1768 
1769 	/*
1770 	 * We don't need to rewrite the page-tables if either we've done
1771 	 * it already or we have KASLR enabled and therefore have not
1772 	 * created any global mappings at all.
1773 	 */
1774 	if (arm64_use_ng_mappings)
1775 		return;
1776 
1777 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1778 
1779 	if (!cpu) {
1780 		alloc = __get_free_pages(GFP_ATOMIC | __GFP_ZERO, order);
1781 		kpti_ng_temp_pgd = (pgd_t *)(alloc + (levels - 1) * PAGE_SIZE);
1782 		kpti_ng_temp_alloc = kpti_ng_temp_pgd_pa = __pa(kpti_ng_temp_pgd);
1783 
1784 		//
1785 		// Create a minimal page table hierarchy that permits us to map
1786 		// the swapper page tables temporarily as we traverse them.
1787 		//
1788 		// The physical pages are laid out as follows:
1789 		//
1790 		// +--------+-/-------+-/------ +-\\--------+
1791 		// :  PTE[] : | PMD[] : | PUD[] : || PGD[]  :
1792 		// +--------+-\-------+-\------ +-//--------+
1793 		//      ^
1794 		// The first page is mapped into this hierarchy at a PMD_SHIFT
1795 		// aligned virtual address, so that we can manipulate the PTE
1796 		// level entries while the mapping is active. The first entry
1797 		// covers the PTE[] page itself, the remaining entries are free
1798 		// to be used as a ad-hoc fixmap.
1799 		//
1800 		create_kpti_ng_temp_pgd(kpti_ng_temp_pgd, __pa(alloc),
1801 					KPTI_NG_TEMP_VA, PAGE_SIZE, PAGE_KERNEL,
1802 					kpti_ng_pgd_alloc, 0);
1803 	}
1804 
1805 	cpu_install_idmap();
1806 	remap_fn(cpu, num_online_cpus(), kpti_ng_temp_pgd_pa, KPTI_NG_TEMP_VA);
1807 	cpu_uninstall_idmap();
1808 
1809 	if (!cpu) {
1810 		free_pages(alloc, order);
1811 		arm64_use_ng_mappings = true;
1812 	}
1813 }
1814 #else
1815 static void
1816 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1817 {
1818 }
1819 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1820 
1821 static int __init parse_kpti(char *str)
1822 {
1823 	bool enabled;
1824 	int ret = kstrtobool(str, &enabled);
1825 
1826 	if (ret)
1827 		return ret;
1828 
1829 	__kpti_forced = enabled ? 1 : -1;
1830 	return 0;
1831 }
1832 early_param("kpti", parse_kpti);
1833 
1834 #ifdef CONFIG_ARM64_HW_AFDBM
1835 static inline void __cpu_enable_hw_dbm(void)
1836 {
1837 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1838 
1839 	write_sysreg(tcr, tcr_el1);
1840 	isb();
1841 	local_flush_tlb_all();
1842 }
1843 
1844 static bool cpu_has_broken_dbm(void)
1845 {
1846 	/* List of CPUs which have broken DBM support. */
1847 	static const struct midr_range cpus[] = {
1848 #ifdef CONFIG_ARM64_ERRATUM_1024718
1849 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1850 		/* Kryo4xx Silver (rdpe => r1p0) */
1851 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1852 #endif
1853 #ifdef CONFIG_ARM64_ERRATUM_2051678
1854 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1855 #endif
1856 		{},
1857 	};
1858 
1859 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1860 }
1861 
1862 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1863 {
1864 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1865 	       !cpu_has_broken_dbm();
1866 }
1867 
1868 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1869 {
1870 	if (cpu_can_use_dbm(cap))
1871 		__cpu_enable_hw_dbm();
1872 }
1873 
1874 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1875 		       int __unused)
1876 {
1877 	static bool detected = false;
1878 	/*
1879 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1880 	 * run a mix of CPUs with and without the feature. So, we
1881 	 * unconditionally enable the capability to allow any late CPU
1882 	 * to use the feature. We only enable the control bits on the
1883 	 * CPU, if it actually supports.
1884 	 *
1885 	 * We have to make sure we print the "feature" detection only
1886 	 * when at least one CPU actually uses it. So check if this CPU
1887 	 * can actually use it and print the message exactly once.
1888 	 *
1889 	 * This is safe as all CPUs (including secondary CPUs - due to the
1890 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1891 	 * goes through the "matches" check exactly once. Also if a CPU
1892 	 * matches the criteria, it is guaranteed that the CPU will turn
1893 	 * the DBM on, as the capability is unconditionally enabled.
1894 	 */
1895 	if (!detected && cpu_can_use_dbm(cap)) {
1896 		detected = true;
1897 		pr_info("detected: Hardware dirty bit management\n");
1898 	}
1899 
1900 	return true;
1901 }
1902 
1903 #endif
1904 
1905 #ifdef CONFIG_ARM64_AMU_EXTN
1906 
1907 /*
1908  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1909  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1910  * information regarding all the events that it supports. When a CPU bit is
1911  * set in the cpumask, the user of this feature can only rely on the presence
1912  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1913  * counters are enabled or access to these counters is enabled by code
1914  * executed at higher exception levels (firmware).
1915  */
1916 static struct cpumask amu_cpus __read_mostly;
1917 
1918 bool cpu_has_amu_feat(int cpu)
1919 {
1920 	return cpumask_test_cpu(cpu, &amu_cpus);
1921 }
1922 
1923 int get_cpu_with_amu_feat(void)
1924 {
1925 	return cpumask_any(&amu_cpus);
1926 }
1927 
1928 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1929 {
1930 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1931 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1932 			smp_processor_id());
1933 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1934 
1935 		/* 0 reference values signal broken/disabled counters */
1936 		if (!this_cpu_has_cap(ARM64_WORKAROUND_2457168))
1937 			update_freq_counters_refs();
1938 	}
1939 }
1940 
1941 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1942 		    int __unused)
1943 {
1944 	/*
1945 	 * The AMU extension is a non-conflicting feature: the kernel can
1946 	 * safely run a mix of CPUs with and without support for the
1947 	 * activity monitors extension. Therefore, unconditionally enable
1948 	 * the capability to allow any late CPU to use the feature.
1949 	 *
1950 	 * With this feature unconditionally enabled, the cpu_enable
1951 	 * function will be called for all CPUs that match the criteria,
1952 	 * including secondary and hotplugged, marking this feature as
1953 	 * present on that respective CPU. The enable function will also
1954 	 * print a detection message.
1955 	 */
1956 
1957 	return true;
1958 }
1959 #else
1960 int get_cpu_with_amu_feat(void)
1961 {
1962 	return nr_cpu_ids;
1963 }
1964 #endif
1965 
1966 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1967 {
1968 	return is_kernel_in_hyp_mode();
1969 }
1970 
1971 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1972 {
1973 	/*
1974 	 * Copy register values that aren't redirected by hardware.
1975 	 *
1976 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1977 	 * this value to tpidr_el2 before we patch the code. Once we've done
1978 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1979 	 * do anything here.
1980 	 */
1981 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1982 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1983 }
1984 
1985 static bool has_nested_virt_support(const struct arm64_cpu_capabilities *cap,
1986 				    int scope)
1987 {
1988 	if (kvm_get_mode() != KVM_MODE_NV)
1989 		return false;
1990 
1991 	if (!has_cpuid_feature(cap, scope)) {
1992 		pr_warn("unavailable: %s\n", cap->desc);
1993 		return false;
1994 	}
1995 
1996 	return true;
1997 }
1998 
1999 #ifdef CONFIG_ARM64_PAN
2000 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
2001 {
2002 	/*
2003 	 * We modify PSTATE. This won't work from irq context as the PSTATE
2004 	 * is discarded once we return from the exception.
2005 	 */
2006 	WARN_ON_ONCE(in_interrupt());
2007 
2008 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
2009 	set_pstate_pan(1);
2010 }
2011 #endif /* CONFIG_ARM64_PAN */
2012 
2013 #ifdef CONFIG_ARM64_RAS_EXTN
2014 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
2015 {
2016 	/* Firmware may have left a deferred SError in this register. */
2017 	write_sysreg_s(0, SYS_DISR_EL1);
2018 }
2019 #endif /* CONFIG_ARM64_RAS_EXTN */
2020 
2021 #ifdef CONFIG_ARM64_PTR_AUTH
2022 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
2023 {
2024 	int boot_val, sec_val;
2025 
2026 	/* We don't expect to be called with SCOPE_SYSTEM */
2027 	WARN_ON(scope == SCOPE_SYSTEM);
2028 	/*
2029 	 * The ptr-auth feature levels are not intercompatible with lower
2030 	 * levels. Hence we must match ptr-auth feature level of the secondary
2031 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
2032 	 * from the sanitised register whereas direct register read is done for
2033 	 * the secondary CPUs.
2034 	 * The sanitised feature state is guaranteed to match that of the
2035 	 * boot CPU as a mismatched secondary CPU is parked before it gets
2036 	 * a chance to update the state, with the capability.
2037 	 */
2038 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
2039 					       entry->field_pos, entry->sign);
2040 	if (scope & SCOPE_BOOT_CPU)
2041 		return boot_val >= entry->min_field_value;
2042 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
2043 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
2044 					      entry->field_pos, entry->sign);
2045 	return (sec_val >= entry->min_field_value) && (sec_val == boot_val);
2046 }
2047 
2048 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
2049 				     int scope)
2050 {
2051 	bool api = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
2052 	bool apa = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5], scope);
2053 	bool apa3 = has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3], scope);
2054 
2055 	return apa || apa3 || api;
2056 }
2057 
2058 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
2059 			     int __unused)
2060 {
2061 	bool gpi = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
2062 	bool gpa = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5);
2063 	bool gpa3 = __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3);
2064 
2065 	return gpa || gpa3 || gpi;
2066 }
2067 #endif /* CONFIG_ARM64_PTR_AUTH */
2068 
2069 #ifdef CONFIG_ARM64_E0PD
2070 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
2071 {
2072 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
2073 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
2074 }
2075 #endif /* CONFIG_ARM64_E0PD */
2076 
2077 #ifdef CONFIG_ARM64_PSEUDO_NMI
2078 static bool enable_pseudo_nmi;
2079 
2080 static int __init early_enable_pseudo_nmi(char *p)
2081 {
2082 	return kstrtobool(p, &enable_pseudo_nmi);
2083 }
2084 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
2085 
2086 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
2087 				   int scope)
2088 {
2089 	/*
2090 	 * ARM64_HAS_GIC_CPUIF_SYSREGS has a lower index, and is a boot CPU
2091 	 * feature, so will be detected earlier.
2092 	 */
2093 	BUILD_BUG_ON(ARM64_HAS_GIC_PRIO_MASKING <= ARM64_HAS_GIC_CPUIF_SYSREGS);
2094 	if (!cpus_have_cap(ARM64_HAS_GIC_CPUIF_SYSREGS))
2095 		return false;
2096 
2097 	return enable_pseudo_nmi;
2098 }
2099 
2100 static bool has_gic_prio_relaxed_sync(const struct arm64_cpu_capabilities *entry,
2101 				      int scope)
2102 {
2103 	/*
2104 	 * If we're not using priority masking then we won't be poking PMR_EL1,
2105 	 * and there's no need to relax synchronization of writes to it, and
2106 	 * ICC_CTLR_EL1 might not be accessible and we must avoid reads from
2107 	 * that.
2108 	 *
2109 	 * ARM64_HAS_GIC_PRIO_MASKING has a lower index, and is a boot CPU
2110 	 * feature, so will be detected earlier.
2111 	 */
2112 	BUILD_BUG_ON(ARM64_HAS_GIC_PRIO_RELAXED_SYNC <= ARM64_HAS_GIC_PRIO_MASKING);
2113 	if (!cpus_have_cap(ARM64_HAS_GIC_PRIO_MASKING))
2114 		return false;
2115 
2116 	/*
2117 	 * When Priority Mask Hint Enable (PMHE) == 0b0, PMR is not used as a
2118 	 * hint for interrupt distribution, a DSB is not necessary when
2119 	 * unmasking IRQs via PMR, and we can relax the barrier to a NOP.
2120 	 *
2121 	 * Linux itself doesn't use 1:N distribution, so has no need to
2122 	 * set PMHE. The only reason to have it set is if EL3 requires it
2123 	 * (and we can't change it).
2124 	 */
2125 	return (gic_read_ctlr() & ICC_CTLR_EL1_PMHE_MASK) == 0;
2126 }
2127 #endif
2128 
2129 #ifdef CONFIG_ARM64_BTI
2130 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
2131 {
2132 	/*
2133 	 * Use of X16/X17 for tail-calls and trampolines that jump to
2134 	 * function entry points using BR is a requirement for
2135 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
2136 	 * So, be strict and forbid other BRs using other registers to
2137 	 * jump onto a PACIxSP instruction:
2138 	 */
2139 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
2140 	isb();
2141 }
2142 #endif /* CONFIG_ARM64_BTI */
2143 
2144 #ifdef CONFIG_ARM64_MTE
2145 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
2146 {
2147 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
2148 
2149 	mte_cpu_setup();
2150 
2151 	/*
2152 	 * Clear the tags in the zero page. This needs to be done via the
2153 	 * linear map which has the Tagged attribute.
2154 	 */
2155 	if (try_page_mte_tagging(ZERO_PAGE(0))) {
2156 		mte_clear_page_tags(lm_alias(empty_zero_page));
2157 		set_page_mte_tagged(ZERO_PAGE(0));
2158 	}
2159 
2160 	kasan_init_hw_tags_cpu();
2161 }
2162 #endif /* CONFIG_ARM64_MTE */
2163 
2164 static void elf_hwcap_fixup(void)
2165 {
2166 #ifdef CONFIG_ARM64_ERRATUM_1742098
2167 	if (cpus_have_const_cap(ARM64_WORKAROUND_1742098))
2168 		compat_elf_hwcap2 &= ~COMPAT_HWCAP2_AES;
2169 #endif /* ARM64_ERRATUM_1742098 */
2170 }
2171 
2172 #ifdef CONFIG_KVM
2173 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
2174 {
2175 	return kvm_get_mode() == KVM_MODE_PROTECTED;
2176 }
2177 #endif /* CONFIG_KVM */
2178 
2179 static void cpu_trap_el0_impdef(const struct arm64_cpu_capabilities *__unused)
2180 {
2181 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_TIDCP);
2182 }
2183 
2184 static void cpu_enable_dit(const struct arm64_cpu_capabilities *__unused)
2185 {
2186 	set_pstate_dit(1);
2187 }
2188 
2189 /* Internal helper functions to match cpu capability type */
2190 static bool
2191 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
2192 {
2193 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
2194 }
2195 
2196 static bool
2197 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
2198 {
2199 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
2200 }
2201 
2202 static bool
2203 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
2204 {
2205 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
2206 }
2207 
2208 static const struct arm64_cpu_capabilities arm64_features[] = {
2209 	{
2210 		.capability = ARM64_ALWAYS_BOOT,
2211 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2212 		.matches = has_always,
2213 	},
2214 	{
2215 		.capability = ARM64_ALWAYS_SYSTEM,
2216 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2217 		.matches = has_always,
2218 	},
2219 	{
2220 		.desc = "GIC system register CPU interface",
2221 		.capability = ARM64_HAS_GIC_CPUIF_SYSREGS,
2222 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2223 		.matches = has_useable_gicv3_cpuif,
2224 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, GIC, IMP)
2225 	},
2226 	{
2227 		.desc = "Enhanced Counter Virtualization",
2228 		.capability = ARM64_HAS_ECV,
2229 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2230 		.matches = has_cpuid_feature,
2231 		ARM64_CPUID_FIELDS(ID_AA64MMFR0_EL1, ECV, IMP)
2232 	},
2233 	{
2234 		.desc = "Enhanced Counter Virtualization (CNTPOFF)",
2235 		.capability = ARM64_HAS_ECV_CNTPOFF,
2236 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2237 		.matches = has_cpuid_feature,
2238 		.sys_reg = SYS_ID_AA64MMFR0_EL1,
2239 		.field_pos = ID_AA64MMFR0_EL1_ECV_SHIFT,
2240 		.field_width = 4,
2241 		.sign = FTR_UNSIGNED,
2242 		.min_field_value = ID_AA64MMFR0_EL1_ECV_CNTPOFF,
2243 	},
2244 #ifdef CONFIG_ARM64_PAN
2245 	{
2246 		.desc = "Privileged Access Never",
2247 		.capability = ARM64_HAS_PAN,
2248 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2249 		.matches = has_cpuid_feature,
2250 		.cpu_enable = cpu_enable_pan,
2251 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, IMP)
2252 	},
2253 #endif /* CONFIG_ARM64_PAN */
2254 #ifdef CONFIG_ARM64_EPAN
2255 	{
2256 		.desc = "Enhanced Privileged Access Never",
2257 		.capability = ARM64_HAS_EPAN,
2258 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2259 		.matches = has_cpuid_feature,
2260 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, PAN3)
2261 	},
2262 #endif /* CONFIG_ARM64_EPAN */
2263 #ifdef CONFIG_ARM64_LSE_ATOMICS
2264 	{
2265 		.desc = "LSE atomic instructions",
2266 		.capability = ARM64_HAS_LSE_ATOMICS,
2267 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2268 		.matches = has_cpuid_feature,
2269 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, ATOMIC, IMP)
2270 	},
2271 #endif /* CONFIG_ARM64_LSE_ATOMICS */
2272 	{
2273 		.desc = "Software prefetching using PRFM",
2274 		.capability = ARM64_HAS_NO_HW_PREFETCH,
2275 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2276 		.matches = has_no_hw_prefetch,
2277 	},
2278 	{
2279 		.desc = "Virtualization Host Extensions",
2280 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
2281 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2282 		.matches = runs_at_el2,
2283 		.cpu_enable = cpu_copy_el2regs,
2284 	},
2285 	{
2286 		.desc = "Nested Virtualization Support",
2287 		.capability = ARM64_HAS_NESTED_VIRT,
2288 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2289 		.matches = has_nested_virt_support,
2290 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, NV, IMP)
2291 	},
2292 	{
2293 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2294 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2295 		.matches = has_32bit_el0,
2296 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, EL0, AARCH32)
2297 	},
2298 #ifdef CONFIG_KVM
2299 	{
2300 		.desc = "32-bit EL1 Support",
2301 		.capability = ARM64_HAS_32BIT_EL1,
2302 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2303 		.matches = has_cpuid_feature,
2304 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, EL1, AARCH32)
2305 	},
2306 	{
2307 		.desc = "Protected KVM",
2308 		.capability = ARM64_KVM_PROTECTED_MODE,
2309 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2310 		.matches = is_kvm_protected_mode,
2311 	},
2312 #endif
2313 	{
2314 		.desc = "Kernel page table isolation (KPTI)",
2315 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2316 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2317 		.cpu_enable = kpti_install_ng_mappings,
2318 		.matches = unmap_kernel_at_el0,
2319 		/*
2320 		 * The ID feature fields below are used to indicate that
2321 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2322 		 * more details.
2323 		 */
2324 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, CSV3, IMP)
2325 	},
2326 	{
2327 		/* FP/SIMD is not implemented */
2328 		.capability = ARM64_HAS_NO_FPSIMD,
2329 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2330 		.min_field_value = 0,
2331 		.matches = has_no_fpsimd,
2332 	},
2333 #ifdef CONFIG_ARM64_PMEM
2334 	{
2335 		.desc = "Data cache clean to Point of Persistence",
2336 		.capability = ARM64_HAS_DCPOP,
2337 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2338 		.matches = has_cpuid_feature,
2339 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, DPB, IMP)
2340 	},
2341 	{
2342 		.desc = "Data cache clean to Point of Deep Persistence",
2343 		.capability = ARM64_HAS_DCPODP,
2344 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2345 		.matches = has_cpuid_feature,
2346 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, DPB, DPB2)
2347 	},
2348 #endif
2349 #ifdef CONFIG_ARM64_SVE
2350 	{
2351 		.desc = "Scalable Vector Extension",
2352 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2353 		.capability = ARM64_SVE,
2354 		.cpu_enable = sve_kernel_enable,
2355 		.matches = has_cpuid_feature,
2356 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, SVE, IMP)
2357 	},
2358 #endif /* CONFIG_ARM64_SVE */
2359 #ifdef CONFIG_ARM64_RAS_EXTN
2360 	{
2361 		.desc = "RAS Extension Support",
2362 		.capability = ARM64_HAS_RAS_EXTN,
2363 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2364 		.matches = has_cpuid_feature,
2365 		.cpu_enable = cpu_clear_disr,
2366 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, RAS, IMP)
2367 	},
2368 #endif /* CONFIG_ARM64_RAS_EXTN */
2369 #ifdef CONFIG_ARM64_AMU_EXTN
2370 	{
2371 		/*
2372 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2373 		 * Therefore, don't provide .desc as we don't want the detection
2374 		 * message to be shown until at least one CPU is detected to
2375 		 * support the feature.
2376 		 */
2377 		.capability = ARM64_HAS_AMU_EXTN,
2378 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2379 		.matches = has_amu,
2380 		.cpu_enable = cpu_amu_enable,
2381 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, AMU, IMP)
2382 	},
2383 #endif /* CONFIG_ARM64_AMU_EXTN */
2384 	{
2385 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2386 		.capability = ARM64_HAS_CACHE_IDC,
2387 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2388 		.matches = has_cache_idc,
2389 		.cpu_enable = cpu_emulate_effective_ctr,
2390 	},
2391 	{
2392 		.desc = "Instruction cache invalidation not required for I/D coherence",
2393 		.capability = ARM64_HAS_CACHE_DIC,
2394 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2395 		.matches = has_cache_dic,
2396 	},
2397 	{
2398 		.desc = "Stage-2 Force Write-Back",
2399 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2400 		.capability = ARM64_HAS_STAGE2_FWB,
2401 		.matches = has_cpuid_feature,
2402 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, FWB, IMP)
2403 	},
2404 	{
2405 		.desc = "ARMv8.4 Translation Table Level",
2406 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2407 		.capability = ARM64_HAS_ARMv8_4_TTL,
2408 		.matches = has_cpuid_feature,
2409 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, TTL, IMP)
2410 	},
2411 	{
2412 		.desc = "TLB range maintenance instructions",
2413 		.capability = ARM64_HAS_TLB_RANGE,
2414 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2415 		.matches = has_cpuid_feature,
2416 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, TLB, RANGE)
2417 	},
2418 #ifdef CONFIG_ARM64_HW_AFDBM
2419 	{
2420 		/*
2421 		 * Since we turn this on always, we don't want the user to
2422 		 * think that the feature is available when it may not be.
2423 		 * So hide the description.
2424 		 *
2425 		 * .desc = "Hardware pagetable Dirty Bit Management",
2426 		 *
2427 		 */
2428 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2429 		.capability = ARM64_HW_DBM,
2430 		.matches = has_hw_dbm,
2431 		.cpu_enable = cpu_enable_hw_dbm,
2432 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, HAFDBS, DBM)
2433 	},
2434 #endif
2435 	{
2436 		.desc = "CRC32 instructions",
2437 		.capability = ARM64_HAS_CRC32,
2438 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2439 		.matches = has_cpuid_feature,
2440 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, CRC32, IMP)
2441 	},
2442 	{
2443 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2444 		.capability = ARM64_SSBS,
2445 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2446 		.matches = has_cpuid_feature,
2447 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SSBS, IMP)
2448 	},
2449 #ifdef CONFIG_ARM64_CNP
2450 	{
2451 		.desc = "Common not Private translations",
2452 		.capability = ARM64_HAS_CNP,
2453 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2454 		.matches = has_useable_cnp,
2455 		.cpu_enable = cpu_enable_cnp,
2456 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, CnP, IMP)
2457 	},
2458 #endif
2459 	{
2460 		.desc = "Speculation barrier (SB)",
2461 		.capability = ARM64_HAS_SB,
2462 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2463 		.matches = has_cpuid_feature,
2464 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, SB, IMP)
2465 	},
2466 #ifdef CONFIG_ARM64_PTR_AUTH
2467 	{
2468 		.desc = "Address authentication (architected QARMA5 algorithm)",
2469 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA5,
2470 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2471 		.matches = has_address_auth_cpucap,
2472 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, APA, PAuth)
2473 	},
2474 	{
2475 		.desc = "Address authentication (architected QARMA3 algorithm)",
2476 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH_QARMA3,
2477 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2478 		.matches = has_address_auth_cpucap,
2479 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, APA3, PAuth)
2480 	},
2481 	{
2482 		.desc = "Address authentication (IMP DEF algorithm)",
2483 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2484 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2485 		.matches = has_address_auth_cpucap,
2486 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, API, PAuth)
2487 	},
2488 	{
2489 		.capability = ARM64_HAS_ADDRESS_AUTH,
2490 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2491 		.matches = has_address_auth_metacap,
2492 	},
2493 	{
2494 		.desc = "Generic authentication (architected QARMA5 algorithm)",
2495 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA5,
2496 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2497 		.matches = has_cpuid_feature,
2498 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, GPA, IMP)
2499 	},
2500 	{
2501 		.desc = "Generic authentication (architected QARMA3 algorithm)",
2502 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH_QARMA3,
2503 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2504 		.matches = has_cpuid_feature,
2505 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, GPA3, IMP)
2506 	},
2507 	{
2508 		.desc = "Generic authentication (IMP DEF algorithm)",
2509 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2510 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2511 		.matches = has_cpuid_feature,
2512 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, GPI, IMP)
2513 	},
2514 	{
2515 		.capability = ARM64_HAS_GENERIC_AUTH,
2516 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2517 		.matches = has_generic_auth,
2518 	},
2519 #endif /* CONFIG_ARM64_PTR_AUTH */
2520 #ifdef CONFIG_ARM64_PSEUDO_NMI
2521 	{
2522 		/*
2523 		 * Depends on having GICv3
2524 		 */
2525 		.desc = "IRQ priority masking",
2526 		.capability = ARM64_HAS_GIC_PRIO_MASKING,
2527 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2528 		.matches = can_use_gic_priorities,
2529 	},
2530 	{
2531 		/*
2532 		 * Depends on ARM64_HAS_GIC_PRIO_MASKING
2533 		 */
2534 		.capability = ARM64_HAS_GIC_PRIO_RELAXED_SYNC,
2535 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2536 		.matches = has_gic_prio_relaxed_sync,
2537 	},
2538 #endif
2539 #ifdef CONFIG_ARM64_E0PD
2540 	{
2541 		.desc = "E0PD",
2542 		.capability = ARM64_HAS_E0PD,
2543 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2544 		.cpu_enable = cpu_enable_e0pd,
2545 		.matches = has_cpuid_feature,
2546 		ARM64_CPUID_FIELDS(ID_AA64MMFR2_EL1, E0PD, IMP)
2547 	},
2548 #endif
2549 	{
2550 		.desc = "Random Number Generator",
2551 		.capability = ARM64_HAS_RNG,
2552 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2553 		.matches = has_cpuid_feature,
2554 		ARM64_CPUID_FIELDS(ID_AA64ISAR0_EL1, RNDR, IMP)
2555 	},
2556 #ifdef CONFIG_ARM64_BTI
2557 	{
2558 		.desc = "Branch Target Identification",
2559 		.capability = ARM64_BTI,
2560 #ifdef CONFIG_ARM64_BTI_KERNEL
2561 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2562 #else
2563 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2564 #endif
2565 		.matches = has_cpuid_feature,
2566 		.cpu_enable = bti_enable,
2567 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, BT, IMP)
2568 	},
2569 #endif
2570 #ifdef CONFIG_ARM64_MTE
2571 	{
2572 		.desc = "Memory Tagging Extension",
2573 		.capability = ARM64_MTE,
2574 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2575 		.matches = has_cpuid_feature,
2576 		.cpu_enable = cpu_enable_mte,
2577 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, MTE, MTE2)
2578 	},
2579 	{
2580 		.desc = "Asymmetric MTE Tag Check Fault",
2581 		.capability = ARM64_MTE_ASYMM,
2582 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2583 		.matches = has_cpuid_feature,
2584 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, MTE, MTE3)
2585 	},
2586 #endif /* CONFIG_ARM64_MTE */
2587 	{
2588 		.desc = "RCpc load-acquire (LDAPR)",
2589 		.capability = ARM64_HAS_LDAPR,
2590 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2591 		.matches = has_cpuid_feature,
2592 		ARM64_CPUID_FIELDS(ID_AA64ISAR1_EL1, LRCPC, IMP)
2593 	},
2594 #ifdef CONFIG_ARM64_SME
2595 	{
2596 		.desc = "Scalable Matrix Extension",
2597 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2598 		.capability = ARM64_SME,
2599 		.matches = has_cpuid_feature,
2600 		.cpu_enable = sme_kernel_enable,
2601 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SME, IMP)
2602 	},
2603 	/* FA64 should be sorted after the base SME capability */
2604 	{
2605 		.desc = "FA64",
2606 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2607 		.capability = ARM64_SME_FA64,
2608 		.matches = has_cpuid_feature,
2609 		.cpu_enable = fa64_kernel_enable,
2610 		ARM64_CPUID_FIELDS(ID_AA64SMFR0_EL1, FA64, IMP)
2611 	},
2612 	{
2613 		.desc = "SME2",
2614 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2615 		.capability = ARM64_SME2,
2616 		.matches = has_cpuid_feature,
2617 		.cpu_enable = sme2_kernel_enable,
2618 		ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, SME, SME2)
2619 	},
2620 #endif /* CONFIG_ARM64_SME */
2621 	{
2622 		.desc = "WFx with timeout",
2623 		.capability = ARM64_HAS_WFXT,
2624 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2625 		.matches = has_cpuid_feature,
2626 		ARM64_CPUID_FIELDS(ID_AA64ISAR2_EL1, WFxT, IMP)
2627 	},
2628 	{
2629 		.desc = "Trap EL0 IMPLEMENTATION DEFINED functionality",
2630 		.capability = ARM64_HAS_TIDCP1,
2631 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2632 		.matches = has_cpuid_feature,
2633 		.cpu_enable = cpu_trap_el0_impdef,
2634 		ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, TIDCP1, IMP)
2635 	},
2636 	{
2637 		.desc = "Data independent timing control (DIT)",
2638 		.capability = ARM64_HAS_DIT,
2639 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2640 		.matches = has_cpuid_feature,
2641 		.cpu_enable = cpu_enable_dit,
2642 		ARM64_CPUID_FIELDS(ID_AA64PFR0_EL1, DIT, IMP)
2643 	},
2644 	{},
2645 };
2646 
2647 #define HWCAP_CPUID_MATCH(reg, field, min_value)			\
2648 		.matches = has_user_cpuid_feature,			\
2649 		ARM64_CPUID_FIELDS(reg, field, min_value)
2650 
2651 #define __HWCAP_CAP(name, cap_type, cap)					\
2652 		.desc = name,							\
2653 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2654 		.hwcap_type = cap_type,						\
2655 		.hwcap = cap,							\
2656 
2657 #define HWCAP_CAP(reg, field, min_value, cap_type, cap)		\
2658 	{									\
2659 		__HWCAP_CAP(#cap, cap_type, cap)				\
2660 		HWCAP_CPUID_MATCH(reg, field, min_value) 		\
2661 	}
2662 
2663 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2664 	{									\
2665 		__HWCAP_CAP(#cap, cap_type, cap)				\
2666 		.matches = cpucap_multi_entry_cap_matches,			\
2667 		.match_list = list,						\
2668 	}
2669 
2670 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2671 	{									\
2672 		__HWCAP_CAP(#cap, cap_type, cap)				\
2673 		.matches = match,						\
2674 	}
2675 
2676 #ifdef CONFIG_ARM64_PTR_AUTH
2677 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2678 	{
2679 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, APA, PAuth)
2680 	},
2681 	{
2682 		HWCAP_CPUID_MATCH(ID_AA64ISAR2_EL1, APA3, PAuth)
2683 	},
2684 	{
2685 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, API, PAuth)
2686 	},
2687 	{},
2688 };
2689 
2690 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2691 	{
2692 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, GPA, IMP)
2693 	},
2694 	{
2695 		HWCAP_CPUID_MATCH(ID_AA64ISAR2_EL1, GPA3, IMP)
2696 	},
2697 	{
2698 		HWCAP_CPUID_MATCH(ID_AA64ISAR1_EL1, GPI, IMP)
2699 	},
2700 	{},
2701 };
2702 #endif
2703 
2704 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2705 	HWCAP_CAP(ID_AA64ISAR0_EL1, AES, PMULL, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2706 	HWCAP_CAP(ID_AA64ISAR0_EL1, AES, AES, CAP_HWCAP, KERNEL_HWCAP_AES),
2707 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA1, IMP, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2708 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA2, SHA256, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2709 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA2, SHA512, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2710 	HWCAP_CAP(ID_AA64ISAR0_EL1, CRC32, IMP, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2711 	HWCAP_CAP(ID_AA64ISAR0_EL1, ATOMIC, IMP, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2712 	HWCAP_CAP(ID_AA64ISAR0_EL1, RDM, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2713 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA3, IMP, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2714 	HWCAP_CAP(ID_AA64ISAR0_EL1, SM3, IMP, CAP_HWCAP, KERNEL_HWCAP_SM3),
2715 	HWCAP_CAP(ID_AA64ISAR0_EL1, SM4, IMP, CAP_HWCAP, KERNEL_HWCAP_SM4),
2716 	HWCAP_CAP(ID_AA64ISAR0_EL1, DP, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2717 	HWCAP_CAP(ID_AA64ISAR0_EL1, FHM, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2718 	HWCAP_CAP(ID_AA64ISAR0_EL1, TS, FLAGM, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2719 	HWCAP_CAP(ID_AA64ISAR0_EL1, TS, FLAGM2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2720 	HWCAP_CAP(ID_AA64ISAR0_EL1, RNDR, IMP, CAP_HWCAP, KERNEL_HWCAP_RNG),
2721 	HWCAP_CAP(ID_AA64PFR0_EL1, FP, IMP, CAP_HWCAP, KERNEL_HWCAP_FP),
2722 	HWCAP_CAP(ID_AA64PFR0_EL1, FP, FP16, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2723 	HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2724 	HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, FP16, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2725 	HWCAP_CAP(ID_AA64PFR0_EL1, DIT, IMP, CAP_HWCAP, KERNEL_HWCAP_DIT),
2726 	HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, IMP, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2727 	HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, DPB2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2728 	HWCAP_CAP(ID_AA64ISAR1_EL1, JSCVT, IMP, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2729 	HWCAP_CAP(ID_AA64ISAR1_EL1, FCMA, IMP, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2730 	HWCAP_CAP(ID_AA64ISAR1_EL1, LRCPC, IMP, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2731 	HWCAP_CAP(ID_AA64ISAR1_EL1, LRCPC, LRCPC2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2732 	HWCAP_CAP(ID_AA64ISAR1_EL1, FRINTTS, IMP, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2733 	HWCAP_CAP(ID_AA64ISAR1_EL1, SB, IMP, CAP_HWCAP, KERNEL_HWCAP_SB),
2734 	HWCAP_CAP(ID_AA64ISAR1_EL1, BF16, IMP, CAP_HWCAP, KERNEL_HWCAP_BF16),
2735 	HWCAP_CAP(ID_AA64ISAR1_EL1, BF16, EBF16, CAP_HWCAP, KERNEL_HWCAP_EBF16),
2736 	HWCAP_CAP(ID_AA64ISAR1_EL1, DGH, IMP, CAP_HWCAP, KERNEL_HWCAP_DGH),
2737 	HWCAP_CAP(ID_AA64ISAR1_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2738 	HWCAP_CAP(ID_AA64MMFR2_EL1, AT, IMP, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2739 #ifdef CONFIG_ARM64_SVE
2740 	HWCAP_CAP(ID_AA64PFR0_EL1, SVE, IMP, CAP_HWCAP, KERNEL_HWCAP_SVE),
2741 	HWCAP_CAP(ID_AA64ZFR0_EL1, SVEver, SVE2p1, CAP_HWCAP, KERNEL_HWCAP_SVE2P1),
2742 	HWCAP_CAP(ID_AA64ZFR0_EL1, SVEver, SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2743 	HWCAP_CAP(ID_AA64ZFR0_EL1, AES, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2744 	HWCAP_CAP(ID_AA64ZFR0_EL1, AES, PMULL128, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2745 	HWCAP_CAP(ID_AA64ZFR0_EL1, BitPerm, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2746 	HWCAP_CAP(ID_AA64ZFR0_EL1, BF16, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2747 	HWCAP_CAP(ID_AA64ZFR0_EL1, BF16, EBF16, CAP_HWCAP, KERNEL_HWCAP_SVE_EBF16),
2748 	HWCAP_CAP(ID_AA64ZFR0_EL1, SHA3, IMP, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2749 	HWCAP_CAP(ID_AA64ZFR0_EL1, SM4, IMP, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2750 	HWCAP_CAP(ID_AA64ZFR0_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2751 	HWCAP_CAP(ID_AA64ZFR0_EL1, F32MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2752 	HWCAP_CAP(ID_AA64ZFR0_EL1, F64MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2753 #endif
2754 	HWCAP_CAP(ID_AA64PFR1_EL1, SSBS, SSBS2, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2755 #ifdef CONFIG_ARM64_BTI
2756 	HWCAP_CAP(ID_AA64PFR1_EL1, BT, IMP, CAP_HWCAP, KERNEL_HWCAP_BTI),
2757 #endif
2758 #ifdef CONFIG_ARM64_PTR_AUTH
2759 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2760 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2761 #endif
2762 #ifdef CONFIG_ARM64_MTE
2763 	HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE2, CAP_HWCAP, KERNEL_HWCAP_MTE),
2764 	HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE3, CAP_HWCAP, KERNEL_HWCAP_MTE3),
2765 #endif /* CONFIG_ARM64_MTE */
2766 	HWCAP_CAP(ID_AA64MMFR0_EL1, ECV, IMP, CAP_HWCAP, KERNEL_HWCAP_ECV),
2767 	HWCAP_CAP(ID_AA64MMFR1_EL1, AFP, IMP, CAP_HWCAP, KERNEL_HWCAP_AFP),
2768 	HWCAP_CAP(ID_AA64ISAR2_EL1, CSSC, IMP, CAP_HWCAP, KERNEL_HWCAP_CSSC),
2769 	HWCAP_CAP(ID_AA64ISAR2_EL1, RPRFM, IMP, CAP_HWCAP, KERNEL_HWCAP_RPRFM),
2770 	HWCAP_CAP(ID_AA64ISAR2_EL1, RPRES, IMP, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2771 	HWCAP_CAP(ID_AA64ISAR2_EL1, WFxT, IMP, CAP_HWCAP, KERNEL_HWCAP_WFXT),
2772 #ifdef CONFIG_ARM64_SME
2773 	HWCAP_CAP(ID_AA64PFR1_EL1, SME, IMP, CAP_HWCAP, KERNEL_HWCAP_SME),
2774 	HWCAP_CAP(ID_AA64SMFR0_EL1, FA64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_FA64),
2775 	HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2p1, CAP_HWCAP, KERNEL_HWCAP_SME2P1),
2776 	HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2, CAP_HWCAP, KERNEL_HWCAP_SME2),
2777 	HWCAP_CAP(ID_AA64SMFR0_EL1, I16I64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I64),
2778 	HWCAP_CAP(ID_AA64SMFR0_EL1, F64F64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F64F64),
2779 	HWCAP_CAP(ID_AA64SMFR0_EL1, I16I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I32),
2780 	HWCAP_CAP(ID_AA64SMFR0_EL1, B16B16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16B16),
2781 	HWCAP_CAP(ID_AA64SMFR0_EL1, F16F16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F16),
2782 	HWCAP_CAP(ID_AA64SMFR0_EL1, I8I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I8I32),
2783 	HWCAP_CAP(ID_AA64SMFR0_EL1, F16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F32),
2784 	HWCAP_CAP(ID_AA64SMFR0_EL1, B16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16F32),
2785 	HWCAP_CAP(ID_AA64SMFR0_EL1, BI32I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_BI32I32),
2786 	HWCAP_CAP(ID_AA64SMFR0_EL1, F32F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F32F32),
2787 #endif /* CONFIG_ARM64_SME */
2788 	{},
2789 };
2790 
2791 #ifdef CONFIG_COMPAT
2792 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2793 {
2794 	/*
2795 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2796 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2797 	 * check is future proof, by making sure value is non-zero.
2798 	 */
2799 	u32 mvfr1;
2800 
2801 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2802 	if (scope == SCOPE_SYSTEM)
2803 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2804 	else
2805 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2806 
2807 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDSP_SHIFT) &&
2808 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDInt_SHIFT) &&
2809 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_EL1_SIMDLS_SHIFT);
2810 }
2811 #endif
2812 
2813 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2814 #ifdef CONFIG_COMPAT
2815 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2816 	HWCAP_CAP(MVFR1_EL1, SIMDFMAC, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2817 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2818 	HWCAP_CAP(MVFR0_EL1, FPDP, VFPv3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2819 	HWCAP_CAP(MVFR0_EL1, FPDP, VFPv3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2820 	HWCAP_CAP(MVFR1_EL1, FPHP, FP16, CAP_COMPAT_HWCAP, COMPAT_HWCAP_FPHP),
2821 	HWCAP_CAP(MVFR1_EL1, SIMDHP, SIMDHP_FLOAT, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDHP),
2822 	HWCAP_CAP(ID_ISAR5_EL1, AES, VMULL, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2823 	HWCAP_CAP(ID_ISAR5_EL1, AES, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2824 	HWCAP_CAP(ID_ISAR5_EL1, SHA1, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2825 	HWCAP_CAP(ID_ISAR5_EL1, SHA2, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2826 	HWCAP_CAP(ID_ISAR5_EL1, CRC32, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2827 	HWCAP_CAP(ID_ISAR6_EL1, DP, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDDP),
2828 	HWCAP_CAP(ID_ISAR6_EL1, FHM, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDFHM),
2829 	HWCAP_CAP(ID_ISAR6_EL1, SB, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SB),
2830 	HWCAP_CAP(ID_ISAR6_EL1, BF16, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDBF16),
2831 	HWCAP_CAP(ID_ISAR6_EL1, I8MM, IMP, CAP_COMPAT_HWCAP, COMPAT_HWCAP_I8MM),
2832 	HWCAP_CAP(ID_PFR2_EL1, SSBS, IMP, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SSBS),
2833 #endif
2834 	{},
2835 };
2836 
2837 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2838 {
2839 	switch (cap->hwcap_type) {
2840 	case CAP_HWCAP:
2841 		cpu_set_feature(cap->hwcap);
2842 		break;
2843 #ifdef CONFIG_COMPAT
2844 	case CAP_COMPAT_HWCAP:
2845 		compat_elf_hwcap |= (u32)cap->hwcap;
2846 		break;
2847 	case CAP_COMPAT_HWCAP2:
2848 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2849 		break;
2850 #endif
2851 	default:
2852 		WARN_ON(1);
2853 		break;
2854 	}
2855 }
2856 
2857 /* Check if we have a particular HWCAP enabled */
2858 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2859 {
2860 	bool rc;
2861 
2862 	switch (cap->hwcap_type) {
2863 	case CAP_HWCAP:
2864 		rc = cpu_have_feature(cap->hwcap);
2865 		break;
2866 #ifdef CONFIG_COMPAT
2867 	case CAP_COMPAT_HWCAP:
2868 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2869 		break;
2870 	case CAP_COMPAT_HWCAP2:
2871 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2872 		break;
2873 #endif
2874 	default:
2875 		WARN_ON(1);
2876 		rc = false;
2877 	}
2878 
2879 	return rc;
2880 }
2881 
2882 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2883 {
2884 	/* We support emulation of accesses to CPU ID feature registers */
2885 	cpu_set_named_feature(CPUID);
2886 	for (; hwcaps->matches; hwcaps++)
2887 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2888 			cap_set_elf_hwcap(hwcaps);
2889 }
2890 
2891 static void update_cpu_capabilities(u16 scope_mask)
2892 {
2893 	int i;
2894 	const struct arm64_cpu_capabilities *caps;
2895 
2896 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2897 	for (i = 0; i < ARM64_NCAPS; i++) {
2898 		caps = cpu_hwcaps_ptrs[i];
2899 		if (!caps || !(caps->type & scope_mask) ||
2900 		    cpus_have_cap(caps->capability) ||
2901 		    !caps->matches(caps, cpucap_default_scope(caps)))
2902 			continue;
2903 
2904 		if (caps->desc)
2905 			pr_info("detected: %s\n", caps->desc);
2906 		cpus_set_cap(caps->capability);
2907 
2908 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2909 			set_bit(caps->capability, boot_capabilities);
2910 	}
2911 }
2912 
2913 /*
2914  * Enable all the available capabilities on this CPU. The capabilities
2915  * with BOOT_CPU scope are handled separately and hence skipped here.
2916  */
2917 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2918 {
2919 	int i;
2920 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2921 
2922 	for_each_available_cap(i) {
2923 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2924 
2925 		if (WARN_ON(!cap))
2926 			continue;
2927 
2928 		if (!(cap->type & non_boot_scope))
2929 			continue;
2930 
2931 		if (cap->cpu_enable)
2932 			cap->cpu_enable(cap);
2933 	}
2934 	return 0;
2935 }
2936 
2937 /*
2938  * Run through the enabled capabilities and enable() it on all active
2939  * CPUs
2940  */
2941 static void __init enable_cpu_capabilities(u16 scope_mask)
2942 {
2943 	int i;
2944 	const struct arm64_cpu_capabilities *caps;
2945 	bool boot_scope;
2946 
2947 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2948 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2949 
2950 	for (i = 0; i < ARM64_NCAPS; i++) {
2951 		unsigned int num;
2952 
2953 		caps = cpu_hwcaps_ptrs[i];
2954 		if (!caps || !(caps->type & scope_mask))
2955 			continue;
2956 		num = caps->capability;
2957 		if (!cpus_have_cap(num))
2958 			continue;
2959 
2960 		if (boot_scope && caps->cpu_enable)
2961 			/*
2962 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2963 			 * before any secondary CPU boots. Thus, each secondary
2964 			 * will enable the capability as appropriate via
2965 			 * check_local_cpu_capabilities(). The only exception is
2966 			 * the boot CPU, for which the capability must be
2967 			 * enabled here. This approach avoids costly
2968 			 * stop_machine() calls for this case.
2969 			 */
2970 			caps->cpu_enable(caps);
2971 	}
2972 
2973 	/*
2974 	 * For all non-boot scope capabilities, use stop_machine()
2975 	 * as it schedules the work allowing us to modify PSTATE,
2976 	 * instead of on_each_cpu() which uses an IPI, giving us a
2977 	 * PSTATE that disappears when we return.
2978 	 */
2979 	if (!boot_scope)
2980 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2981 			     NULL, cpu_online_mask);
2982 }
2983 
2984 /*
2985  * Run through the list of capabilities to check for conflicts.
2986  * If the system has already detected a capability, take necessary
2987  * action on this CPU.
2988  */
2989 static void verify_local_cpu_caps(u16 scope_mask)
2990 {
2991 	int i;
2992 	bool cpu_has_cap, system_has_cap;
2993 	const struct arm64_cpu_capabilities *caps;
2994 
2995 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2996 
2997 	for (i = 0; i < ARM64_NCAPS; i++) {
2998 		caps = cpu_hwcaps_ptrs[i];
2999 		if (!caps || !(caps->type & scope_mask))
3000 			continue;
3001 
3002 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
3003 		system_has_cap = cpus_have_cap(caps->capability);
3004 
3005 		if (system_has_cap) {
3006 			/*
3007 			 * Check if the new CPU misses an advertised feature,
3008 			 * which is not safe to miss.
3009 			 */
3010 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
3011 				break;
3012 			/*
3013 			 * We have to issue cpu_enable() irrespective of
3014 			 * whether the CPU has it or not, as it is enabeld
3015 			 * system wide. It is upto the call back to take
3016 			 * appropriate action on this CPU.
3017 			 */
3018 			if (caps->cpu_enable)
3019 				caps->cpu_enable(caps);
3020 		} else {
3021 			/*
3022 			 * Check if the CPU has this capability if it isn't
3023 			 * safe to have when the system doesn't.
3024 			 */
3025 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
3026 				break;
3027 		}
3028 	}
3029 
3030 	if (i < ARM64_NCAPS) {
3031 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
3032 			smp_processor_id(), caps->capability,
3033 			caps->desc, system_has_cap, cpu_has_cap);
3034 
3035 		if (cpucap_panic_on_conflict(caps))
3036 			cpu_panic_kernel();
3037 		else
3038 			cpu_die_early();
3039 	}
3040 }
3041 
3042 /*
3043  * Check for CPU features that are used in early boot
3044  * based on the Boot CPU value.
3045  */
3046 static void check_early_cpu_features(void)
3047 {
3048 	verify_cpu_asid_bits();
3049 
3050 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
3051 }
3052 
3053 static void
3054 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
3055 {
3056 
3057 	for (; caps->matches; caps++)
3058 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
3059 			pr_crit("CPU%d: missing HWCAP: %s\n",
3060 					smp_processor_id(), caps->desc);
3061 			cpu_die_early();
3062 		}
3063 }
3064 
3065 static void verify_local_elf_hwcaps(void)
3066 {
3067 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
3068 
3069 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
3070 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
3071 }
3072 
3073 static void verify_sve_features(void)
3074 {
3075 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
3076 	u64 zcr = read_zcr_features();
3077 
3078 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
3079 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
3080 
3081 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SVE)) {
3082 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
3083 			smp_processor_id());
3084 		cpu_die_early();
3085 	}
3086 
3087 	/* Add checks on other ZCR bits here if necessary */
3088 }
3089 
3090 static void verify_sme_features(void)
3091 {
3092 	u64 safe_smcr = read_sanitised_ftr_reg(SYS_SMCR_EL1);
3093 	u64 smcr = read_smcr_features();
3094 
3095 	unsigned int safe_len = safe_smcr & SMCR_ELx_LEN_MASK;
3096 	unsigned int len = smcr & SMCR_ELx_LEN_MASK;
3097 
3098 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SME)) {
3099 		pr_crit("CPU%d: SME: vector length support mismatch\n",
3100 			smp_processor_id());
3101 		cpu_die_early();
3102 	}
3103 
3104 	/* Add checks on other SMCR bits here if necessary */
3105 }
3106 
3107 static void verify_hyp_capabilities(void)
3108 {
3109 	u64 safe_mmfr1, mmfr0, mmfr1;
3110 	int parange, ipa_max;
3111 	unsigned int safe_vmid_bits, vmid_bits;
3112 
3113 	if (!IS_ENABLED(CONFIG_KVM))
3114 		return;
3115 
3116 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
3117 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
3118 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
3119 
3120 	/* Verify VMID bits */
3121 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
3122 	vmid_bits = get_vmid_bits(mmfr1);
3123 	if (vmid_bits < safe_vmid_bits) {
3124 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
3125 		cpu_die_early();
3126 	}
3127 
3128 	/* Verify IPA range */
3129 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
3130 				ID_AA64MMFR0_EL1_PARANGE_SHIFT);
3131 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
3132 	if (ipa_max < get_kvm_ipa_limit()) {
3133 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
3134 		cpu_die_early();
3135 	}
3136 }
3137 
3138 /*
3139  * Run through the enabled system capabilities and enable() it on this CPU.
3140  * The capabilities were decided based on the available CPUs at the boot time.
3141  * Any new CPU should match the system wide status of the capability. If the
3142  * new CPU doesn't have a capability which the system now has enabled, we
3143  * cannot do anything to fix it up and could cause unexpected failures. So
3144  * we park the CPU.
3145  */
3146 static void verify_local_cpu_capabilities(void)
3147 {
3148 	/*
3149 	 * The capabilities with SCOPE_BOOT_CPU are checked from
3150 	 * check_early_cpu_features(), as they need to be verified
3151 	 * on all secondary CPUs.
3152 	 */
3153 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3154 	verify_local_elf_hwcaps();
3155 
3156 	if (system_supports_sve())
3157 		verify_sve_features();
3158 
3159 	if (system_supports_sme())
3160 		verify_sme_features();
3161 
3162 	if (is_hyp_mode_available())
3163 		verify_hyp_capabilities();
3164 }
3165 
3166 void check_local_cpu_capabilities(void)
3167 {
3168 	/*
3169 	 * All secondary CPUs should conform to the early CPU features
3170 	 * in use by the kernel based on boot CPU.
3171 	 */
3172 	check_early_cpu_features();
3173 
3174 	/*
3175 	 * If we haven't finalised the system capabilities, this CPU gets
3176 	 * a chance to update the errata work arounds and local features.
3177 	 * Otherwise, this CPU should verify that it has all the system
3178 	 * advertised capabilities.
3179 	 */
3180 	if (!system_capabilities_finalized())
3181 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
3182 	else
3183 		verify_local_cpu_capabilities();
3184 }
3185 
3186 static void __init setup_boot_cpu_capabilities(void)
3187 {
3188 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
3189 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
3190 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
3191 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
3192 }
3193 
3194 bool this_cpu_has_cap(unsigned int n)
3195 {
3196 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
3197 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
3198 
3199 		if (cap)
3200 			return cap->matches(cap, SCOPE_LOCAL_CPU);
3201 	}
3202 
3203 	return false;
3204 }
3205 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
3206 
3207 /*
3208  * This helper function is used in a narrow window when,
3209  * - The system wide safe registers are set with all the SMP CPUs and,
3210  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
3211  * In all other cases cpus_have_{const_}cap() should be used.
3212  */
3213 static bool __maybe_unused __system_matches_cap(unsigned int n)
3214 {
3215 	if (n < ARM64_NCAPS) {
3216 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
3217 
3218 		if (cap)
3219 			return cap->matches(cap, SCOPE_SYSTEM);
3220 	}
3221 	return false;
3222 }
3223 
3224 void cpu_set_feature(unsigned int num)
3225 {
3226 	set_bit(num, elf_hwcap);
3227 }
3228 
3229 bool cpu_have_feature(unsigned int num)
3230 {
3231 	return test_bit(num, elf_hwcap);
3232 }
3233 EXPORT_SYMBOL_GPL(cpu_have_feature);
3234 
3235 unsigned long cpu_get_elf_hwcap(void)
3236 {
3237 	/*
3238 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
3239 	 * note that for userspace compatibility we guarantee that bits 62
3240 	 * and 63 will always be returned as 0.
3241 	 */
3242 	return elf_hwcap[0];
3243 }
3244 
3245 unsigned long cpu_get_elf_hwcap2(void)
3246 {
3247 	return elf_hwcap[1];
3248 }
3249 
3250 static void __init setup_system_capabilities(void)
3251 {
3252 	/*
3253 	 * We have finalised the system-wide safe feature
3254 	 * registers, finalise the capabilities that depend
3255 	 * on it. Also enable all the available capabilities,
3256 	 * that are not enabled already.
3257 	 */
3258 	update_cpu_capabilities(SCOPE_SYSTEM);
3259 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
3260 }
3261 
3262 void __init setup_cpu_features(void)
3263 {
3264 	u32 cwg;
3265 
3266 	setup_system_capabilities();
3267 	setup_elf_hwcaps(arm64_elf_hwcaps);
3268 
3269 	if (system_supports_32bit_el0()) {
3270 		setup_elf_hwcaps(compat_elf_hwcaps);
3271 		elf_hwcap_fixup();
3272 	}
3273 
3274 	if (system_uses_ttbr0_pan())
3275 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
3276 
3277 	sve_setup();
3278 	sme_setup();
3279 	minsigstksz_setup();
3280 
3281 	/*
3282 	 * Check for sane CTR_EL0.CWG value.
3283 	 */
3284 	cwg = cache_type_cwg();
3285 	if (!cwg)
3286 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
3287 			ARCH_DMA_MINALIGN);
3288 }
3289 
3290 static int enable_mismatched_32bit_el0(unsigned int cpu)
3291 {
3292 	/*
3293 	 * The first 32-bit-capable CPU we detected and so can no longer
3294 	 * be offlined by userspace. -1 indicates we haven't yet onlined
3295 	 * a 32-bit-capable CPU.
3296 	 */
3297 	static int lucky_winner = -1;
3298 
3299 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
3300 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
3301 
3302 	if (cpu_32bit) {
3303 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
3304 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
3305 	}
3306 
3307 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
3308 		return 0;
3309 
3310 	if (lucky_winner >= 0)
3311 		return 0;
3312 
3313 	/*
3314 	 * We've detected a mismatch. We need to keep one of our CPUs with
3315 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
3316 	 * every CPU in the system for a 32-bit task.
3317 	 */
3318 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
3319 							 cpu_active_mask);
3320 	get_cpu_device(lucky_winner)->offline_disabled = true;
3321 	setup_elf_hwcaps(compat_elf_hwcaps);
3322 	elf_hwcap_fixup();
3323 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
3324 		cpu, lucky_winner);
3325 	return 0;
3326 }
3327 
3328 static int __init init_32bit_el0_mask(void)
3329 {
3330 	if (!allow_mismatched_32bit_el0)
3331 		return 0;
3332 
3333 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3334 		return -ENOMEM;
3335 
3336 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3337 				 "arm64/mismatched_32bit_el0:online",
3338 				 enable_mismatched_32bit_el0, NULL);
3339 }
3340 subsys_initcall_sync(init_32bit_el0_mask);
3341 
3342 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3343 {
3344 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir), idmap_pg_dir);
3345 }
3346 
3347 /*
3348  * We emulate only the following system register space.
3349  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 2 - 7]
3350  * See Table C5-6 System instruction encodings for System register accesses,
3351  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3352  */
3353 static inline bool __attribute_const__ is_emulated(u32 id)
3354 {
3355 	return (sys_reg_Op0(id) == 0x3 &&
3356 		sys_reg_CRn(id) == 0x0 &&
3357 		sys_reg_Op1(id) == 0x0 &&
3358 		(sys_reg_CRm(id) == 0 ||
3359 		 ((sys_reg_CRm(id) >= 2) && (sys_reg_CRm(id) <= 7))));
3360 }
3361 
3362 /*
3363  * With CRm == 0, reg should be one of :
3364  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3365  */
3366 static inline int emulate_id_reg(u32 id, u64 *valp)
3367 {
3368 	switch (id) {
3369 	case SYS_MIDR_EL1:
3370 		*valp = read_cpuid_id();
3371 		break;
3372 	case SYS_MPIDR_EL1:
3373 		*valp = SYS_MPIDR_SAFE_VAL;
3374 		break;
3375 	case SYS_REVIDR_EL1:
3376 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3377 		*valp = 0;
3378 		break;
3379 	default:
3380 		return -EINVAL;
3381 	}
3382 
3383 	return 0;
3384 }
3385 
3386 static int emulate_sys_reg(u32 id, u64 *valp)
3387 {
3388 	struct arm64_ftr_reg *regp;
3389 
3390 	if (!is_emulated(id))
3391 		return -EINVAL;
3392 
3393 	if (sys_reg_CRm(id) == 0)
3394 		return emulate_id_reg(id, valp);
3395 
3396 	regp = get_arm64_ftr_reg_nowarn(id);
3397 	if (regp)
3398 		*valp = arm64_ftr_reg_user_value(regp);
3399 	else
3400 		/*
3401 		 * The untracked registers are either IMPLEMENTATION DEFINED
3402 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3403 		 */
3404 		*valp = 0;
3405 	return 0;
3406 }
3407 
3408 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3409 {
3410 	int rc;
3411 	u64 val;
3412 
3413 	rc = emulate_sys_reg(sys_reg, &val);
3414 	if (!rc) {
3415 		pt_regs_write_reg(regs, rt, val);
3416 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3417 	}
3418 	return rc;
3419 }
3420 
3421 bool try_emulate_mrs(struct pt_regs *regs, u32 insn)
3422 {
3423 	u32 sys_reg, rt;
3424 
3425 	if (compat_user_mode(regs) || !aarch64_insn_is_mrs(insn))
3426 		return false;
3427 
3428 	/*
3429 	 * sys_reg values are defined as used in mrs/msr instruction.
3430 	 * shift the imm value to get the encoding.
3431 	 */
3432 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3433 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3434 	return do_emulate_mrs(regs, sys_reg, rt) == 0;
3435 }
3436 
3437 enum mitigation_state arm64_get_meltdown_state(void)
3438 {
3439 	if (__meltdown_safe)
3440 		return SPECTRE_UNAFFECTED;
3441 
3442 	if (arm64_kernel_unmapped_at_el0())
3443 		return SPECTRE_MITIGATED;
3444 
3445 	return SPECTRE_VULNERABLE;
3446 }
3447 
3448 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3449 			  char *buf)
3450 {
3451 	switch (arm64_get_meltdown_state()) {
3452 	case SPECTRE_UNAFFECTED:
3453 		return sprintf(buf, "Not affected\n");
3454 
3455 	case SPECTRE_MITIGATED:
3456 		return sprintf(buf, "Mitigation: PTI\n");
3457 
3458 	default:
3459 		return sprintf(buf, "Vulnerable\n");
3460 	}
3461 }
3462