xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision 9f99d983)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Contains CPU feature definitions
4  *
5  * Copyright (C) 2015 ARM Ltd.
6  *
7  * A note for the weary kernel hacker: the code here is confusing and hard to
8  * follow! That's partly because it's solving a nasty problem, but also because
9  * there's a little bit of over-abstraction that tends to obscure what's going
10  * on behind a maze of helper functions and macros.
11  *
12  * The basic problem is that hardware folks have started gluing together CPUs
13  * with distinct architectural features; in some cases even creating SoCs where
14  * user-visible instructions are available only on a subset of the available
15  * cores. We try to address this by snapshotting the feature registers of the
16  * boot CPU and comparing these with the feature registers of each secondary
17  * CPU when bringing them up. If there is a mismatch, then we update the
18  * snapshot state to indicate the lowest-common denominator of the feature,
19  * known as the "safe" value. This snapshot state can be queried to view the
20  * "sanitised" value of a feature register.
21  *
22  * The sanitised register values are used to decide which capabilities we
23  * have in the system. These may be in the form of traditional "hwcaps"
24  * advertised to userspace or internal "cpucaps" which are used to configure
25  * things like alternative patching and static keys. While a feature mismatch
26  * may result in a TAINT_CPU_OUT_OF_SPEC kernel taint, a capability mismatch
27  * may prevent a CPU from being onlined at all.
28  *
29  * Some implementation details worth remembering:
30  *
31  * - Mismatched features are *always* sanitised to a "safe" value, which
32  *   usually indicates that the feature is not supported.
33  *
34  * - A mismatched feature marked with FTR_STRICT will cause a "SANITY CHECK"
35  *   warning when onlining an offending CPU and the kernel will be tainted
36  *   with TAINT_CPU_OUT_OF_SPEC.
37  *
38  * - Features marked as FTR_VISIBLE have their sanitised value visible to
39  *   userspace. FTR_VISIBLE features in registers that are only visible
40  *   to EL0 by trapping *must* have a corresponding HWCAP so that late
41  *   onlining of CPUs cannot lead to features disappearing at runtime.
42  *
43  * - A "feature" is typically a 4-bit register field. A "capability" is the
44  *   high-level description derived from the sanitised field value.
45  *
46  * - Read the Arm ARM (DDI 0487F.a) section D13.1.3 ("Principles of the ID
47  *   scheme for fields in ID registers") to understand when feature fields
48  *   may be signed or unsigned (FTR_SIGNED and FTR_UNSIGNED accordingly).
49  *
50  * - KVM exposes its own view of the feature registers to guest operating
51  *   systems regardless of FTR_VISIBLE. This is typically driven from the
52  *   sanitised register values to allow virtual CPUs to be migrated between
53  *   arbitrary physical CPUs, but some features not present on the host are
54  *   also advertised and emulated. Look at sys_reg_descs[] for the gory
55  *   details.
56  *
57  * - If the arm64_ftr_bits[] for a register has a missing field, then this
58  *   field is treated as STRICT RES0, including for read_sanitised_ftr_reg().
59  *   This is stronger than FTR_HIDDEN and can be used to hide features from
60  *   KVM guests.
61  */
62 
63 #define pr_fmt(fmt) "CPU features: " fmt
64 
65 #include <linux/bsearch.h>
66 #include <linux/cpumask.h>
67 #include <linux/crash_dump.h>
68 #include <linux/sort.h>
69 #include <linux/stop_machine.h>
70 #include <linux/sysfs.h>
71 #include <linux/types.h>
72 #include <linux/minmax.h>
73 #include <linux/mm.h>
74 #include <linux/cpu.h>
75 #include <linux/kasan.h>
76 #include <asm/cpu.h>
77 #include <asm/cpufeature.h>
78 #include <asm/cpu_ops.h>
79 #include <asm/fpsimd.h>
80 #include <asm/insn.h>
81 #include <asm/kvm_host.h>
82 #include <asm/mmu_context.h>
83 #include <asm/mte.h>
84 #include <asm/processor.h>
85 #include <asm/smp.h>
86 #include <asm/sysreg.h>
87 #include <asm/traps.h>
88 #include <asm/virt.h>
89 
90 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
91 static unsigned long elf_hwcap __read_mostly;
92 
93 #ifdef CONFIG_COMPAT
94 #define COMPAT_ELF_HWCAP_DEFAULT	\
95 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
96 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
97 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
98 				 COMPAT_HWCAP_LPAE)
99 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
100 unsigned int compat_elf_hwcap2 __read_mostly;
101 #endif
102 
103 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
104 EXPORT_SYMBOL(cpu_hwcaps);
105 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
106 
107 /* Need also bit for ARM64_CB_PATCH */
108 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
109 
110 bool arm64_use_ng_mappings = false;
111 EXPORT_SYMBOL(arm64_use_ng_mappings);
112 
113 /*
114  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
115  * support it?
116  */
117 static bool __read_mostly allow_mismatched_32bit_el0;
118 
119 /*
120  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
121  * seen at least one CPU capable of 32-bit EL0.
122  */
123 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
124 
125 /*
126  * Mask of CPUs supporting 32-bit EL0.
127  * Only valid if arm64_mismatched_32bit_el0 is enabled.
128  */
129 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
130 
131 /*
132  * Flag to indicate if we have computed the system wide
133  * capabilities based on the boot time active CPUs. This
134  * will be used to determine if a new booting CPU should
135  * go through the verification process to make sure that it
136  * supports the system capabilities, without using a hotplug
137  * notifier. This is also used to decide if we could use
138  * the fast path for checking constant CPU caps.
139  */
140 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
141 EXPORT_SYMBOL(arm64_const_caps_ready);
142 static inline void finalize_system_capabilities(void)
143 {
144 	static_branch_enable(&arm64_const_caps_ready);
145 }
146 
147 void dump_cpu_features(void)
148 {
149 	/* file-wide pr_fmt adds "CPU features: " prefix */
150 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
151 }
152 
153 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
154 EXPORT_SYMBOL(cpu_hwcap_keys);
155 
156 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
157 	{						\
158 		.sign = SIGNED,				\
159 		.visible = VISIBLE,			\
160 		.strict = STRICT,			\
161 		.type = TYPE,				\
162 		.shift = SHIFT,				\
163 		.width = WIDTH,				\
164 		.safe_val = SAFE_VAL,			\
165 	}
166 
167 /* Define a feature with unsigned values */
168 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
169 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
170 
171 /* Define a feature with a signed value */
172 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
173 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
174 
175 #define ARM64_FTR_END					\
176 	{						\
177 		.width = 0,				\
178 	}
179 
180 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
181 
182 static bool __system_matches_cap(unsigned int n);
183 
184 /*
185  * NOTE: Any changes to the visibility of features should be kept in
186  * sync with the documentation of the CPU feature register ABI.
187  */
188 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
189 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
190 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
192 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
203 	ARM64_FTR_END,
204 };
205 
206 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
214 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
216 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
221 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
223 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
225 	ARM64_FTR_END,
226 };
227 
228 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
229 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
230 	ARM64_FTR_END,
231 };
232 
233 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
235 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
236 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
238 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
239 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
241 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
244 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
245 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
246 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
247 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
250 	ARM64_FTR_END,
251 };
252 
253 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
254 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
255 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
256 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
257 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
258 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
259 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
260 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
261 	ARM64_FTR_END,
262 };
263 
264 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
265 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
266 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
267 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
268 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
269 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
270 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
271 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
272 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
277 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
278 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
279 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
280 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
281 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
282 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
283 	ARM64_FTR_END,
284 };
285 
286 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
287 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
288 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
289 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
290 	/*
291 	 * Page size not being supported at Stage-2 is not fatal. You
292 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
293 	 * your favourite nesting hypervisor.
294 	 *
295 	 * There is a small corner case where the hypervisor explicitly
296 	 * advertises a given granule size at Stage-2 (value 2) on some
297 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
298 	 * vCPUs. Although this is not forbidden by the architecture, it
299 	 * indicates that the hypervisor is being silly (or buggy).
300 	 *
301 	 * We make no effort to cope with this and pretend that if these
302 	 * fields are inconsistent across vCPUs, then it isn't worth
303 	 * trying to bring KVM up.
304 	 */
305 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
306 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
307 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
308 	/*
309 	 * We already refuse to boot CPUs that don't support our configured
310 	 * page size, so we can only detect mismatches for a page size other
311 	 * than the one we're currently using. Unfortunately, SoCs like this
312 	 * exist in the wild so, even though we don't like it, we'll have to go
313 	 * along with it and treat them as non-strict.
314 	 */
315 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
316 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
317 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
318 
319 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
320 	/* Linux shouldn't care about secure memory */
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
324 	/*
325 	 * Differing PARange is fine as long as all peripherals and memory are mapped
326 	 * within the minimum PARange of all CPUs
327 	 */
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
329 	ARM64_FTR_END,
330 };
331 
332 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
333 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
334 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
335 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
344 	ARM64_FTR_END,
345 };
346 
347 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
351 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
352 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
354 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
356 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
357 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
358 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
360 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
361 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
362 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
363 	ARM64_FTR_END,
364 };
365 
366 static const struct arm64_ftr_bits ftr_ctr[] = {
367 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
368 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
369 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
370 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
371 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
372 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
373 	/*
374 	 * Linux can handle differing I-cache policies. Userspace JITs will
375 	 * make use of *minLine.
376 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
377 	 */
378 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
379 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
380 	ARM64_FTR_END,
381 };
382 
383 static struct arm64_ftr_override __ro_after_init no_override = { };
384 
385 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
386 	.name		= "SYS_CTR_EL0",
387 	.ftr_bits	= ftr_ctr,
388 	.override	= &no_override,
389 };
390 
391 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
392 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
393 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
394 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
395 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
396 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
397 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
398 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
400 	ARM64_FTR_END,
401 };
402 
403 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
404 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
405 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
406 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
407 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
408 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
409 	/*
410 	 * We can instantiate multiple PMU instances with different levels
411 	 * of support.
412 	 */
413 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
415 	ARM64_FTR_END,
416 };
417 
418 static const struct arm64_ftr_bits ftr_mvfr2[] = {
419 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
420 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
421 	ARM64_FTR_END,
422 };
423 
424 static const struct arm64_ftr_bits ftr_dczid[] = {
425 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
426 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
427 	ARM64_FTR_END,
428 };
429 
430 static const struct arm64_ftr_bits ftr_gmid[] = {
431 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, SYS_GMID_EL1_BS_SHIFT, 4, 0),
432 	ARM64_FTR_END,
433 };
434 
435 static const struct arm64_ftr_bits ftr_id_isar0[] = {
436 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
443 	ARM64_FTR_END,
444 };
445 
446 static const struct arm64_ftr_bits ftr_id_isar5[] = {
447 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
448 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
449 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
453 	ARM64_FTR_END,
454 };
455 
456 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
459 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
460 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
461 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
462 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
463 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
464 
465 	/*
466 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
467 	 * external abort on speculative read. It is safe to assume that an
468 	 * SError might be generated than it will not be. Hence it has been
469 	 * classified as FTR_HIGHER_SAFE.
470 	 */
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
472 	ARM64_FTR_END,
473 };
474 
475 static const struct arm64_ftr_bits ftr_id_isar4[] = {
476 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
478 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
479 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
480 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
484 	ARM64_FTR_END,
485 };
486 
487 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
489 	ARM64_FTR_END,
490 };
491 
492 static const struct arm64_ftr_bits ftr_id_isar6[] = {
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
495 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
496 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
500 	ARM64_FTR_END,
501 };
502 
503 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
504 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
505 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
506 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
507 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
510 	ARM64_FTR_END,
511 };
512 
513 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
516 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
517 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
518 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
519 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
521 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
522 	ARM64_FTR_END,
523 };
524 
525 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
526 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
528 	ARM64_FTR_END,
529 };
530 
531 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
532 	/* [31:28] TraceFilt */
533 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
534 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
535 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
536 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
538 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
540 	ARM64_FTR_END,
541 };
542 
543 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
544 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
545 	ARM64_FTR_END,
546 };
547 
548 static const struct arm64_ftr_bits ftr_zcr[] = {
549 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
550 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
551 	ARM64_FTR_END,
552 };
553 
554 /*
555  * Common ftr bits for a 32bit register with all hidden, strict
556  * attributes, with 4bit feature fields and a default safe value of
557  * 0. Covers the following 32bit registers:
558  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
559  */
560 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
561 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
562 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
563 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
564 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
565 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
566 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
568 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
569 	ARM64_FTR_END,
570 };
571 
572 /* Table for a single 32bit feature value */
573 static const struct arm64_ftr_bits ftr_single32[] = {
574 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
575 	ARM64_FTR_END,
576 };
577 
578 static const struct arm64_ftr_bits ftr_raz[] = {
579 	ARM64_FTR_END,
580 };
581 
582 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
583 		.sys_id = id,					\
584 		.reg = 	&(struct arm64_ftr_reg){		\
585 			.name = id_str,				\
586 			.override = (ovr),			\
587 			.ftr_bits = &((table)[0]),		\
588 	}}
589 
590 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
591 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
592 
593 #define ARM64_FTR_REG(id, table)		\
594 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
595 
596 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
597 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
598 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
599 
600 static const struct __ftr_reg_entry {
601 	u32			sys_id;
602 	struct arm64_ftr_reg 	*reg;
603 } arm64_ftr_regs[] = {
604 
605 	/* Op1 = 0, CRn = 0, CRm = 1 */
606 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
607 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
608 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
609 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
610 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
611 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
612 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
613 
614 	/* Op1 = 0, CRn = 0, CRm = 2 */
615 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
616 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
617 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
618 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
619 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
620 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
621 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
622 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
623 
624 	/* Op1 = 0, CRn = 0, CRm = 3 */
625 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
626 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
627 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
628 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
629 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
630 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
631 
632 	/* Op1 = 0, CRn = 0, CRm = 4 */
633 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
634 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
635 			       &id_aa64pfr1_override),
636 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
637 
638 	/* Op1 = 0, CRn = 0, CRm = 5 */
639 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
640 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
641 
642 	/* Op1 = 0, CRn = 0, CRm = 6 */
643 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
644 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
645 			       &id_aa64isar1_override),
646 	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
647 
648 	/* Op1 = 0, CRn = 0, CRm = 7 */
649 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
650 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
651 			       &id_aa64mmfr1_override),
652 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
653 
654 	/* Op1 = 0, CRn = 1, CRm = 2 */
655 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
656 
657 	/* Op1 = 1, CRn = 0, CRm = 0 */
658 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
659 
660 	/* Op1 = 3, CRn = 0, CRm = 0 */
661 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
662 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
663 
664 	/* Op1 = 3, CRn = 14, CRm = 0 */
665 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
666 };
667 
668 static int search_cmp_ftr_reg(const void *id, const void *regp)
669 {
670 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
671 }
672 
673 /*
674  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
675  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
676  * ascending order of sys_id, we use binary search to find a matching
677  * entry.
678  *
679  * returns - Upon success,  matching ftr_reg entry for id.
680  *         - NULL on failure. It is upto the caller to decide
681  *	     the impact of a failure.
682  */
683 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
684 {
685 	const struct __ftr_reg_entry *ret;
686 
687 	ret = bsearch((const void *)(unsigned long)sys_id,
688 			arm64_ftr_regs,
689 			ARRAY_SIZE(arm64_ftr_regs),
690 			sizeof(arm64_ftr_regs[0]),
691 			search_cmp_ftr_reg);
692 	if (ret)
693 		return ret->reg;
694 	return NULL;
695 }
696 
697 /*
698  * get_arm64_ftr_reg - Looks up a feature register entry using
699  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
700  *
701  * returns - Upon success,  matching ftr_reg entry for id.
702  *         - NULL on failure but with an WARN_ON().
703  */
704 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
705 {
706 	struct arm64_ftr_reg *reg;
707 
708 	reg = get_arm64_ftr_reg_nowarn(sys_id);
709 
710 	/*
711 	 * Requesting a non-existent register search is an error. Warn
712 	 * and let the caller handle it.
713 	 */
714 	WARN_ON(!reg);
715 	return reg;
716 }
717 
718 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
719 			       s64 ftr_val)
720 {
721 	u64 mask = arm64_ftr_mask(ftrp);
722 
723 	reg &= ~mask;
724 	reg |= (ftr_val << ftrp->shift) & mask;
725 	return reg;
726 }
727 
728 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
729 				s64 cur)
730 {
731 	s64 ret = 0;
732 
733 	switch (ftrp->type) {
734 	case FTR_EXACT:
735 		ret = ftrp->safe_val;
736 		break;
737 	case FTR_LOWER_SAFE:
738 		ret = min(new, cur);
739 		break;
740 	case FTR_HIGHER_OR_ZERO_SAFE:
741 		if (!cur || !new)
742 			break;
743 		fallthrough;
744 	case FTR_HIGHER_SAFE:
745 		ret = max(new, cur);
746 		break;
747 	default:
748 		BUG();
749 	}
750 
751 	return ret;
752 }
753 
754 static void __init sort_ftr_regs(void)
755 {
756 	unsigned int i;
757 
758 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
759 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
760 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
761 		unsigned int j = 0;
762 
763 		/*
764 		 * Features here must be sorted in descending order with respect
765 		 * to their shift values and should not overlap with each other.
766 		 */
767 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
768 			unsigned int width = ftr_reg->ftr_bits[j].width;
769 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
770 			unsigned int prev_shift;
771 
772 			WARN((shift  + width) > 64,
773 				"%s has invalid feature at shift %d\n",
774 				ftr_reg->name, shift);
775 
776 			/*
777 			 * Skip the first feature. There is nothing to
778 			 * compare against for now.
779 			 */
780 			if (j == 0)
781 				continue;
782 
783 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
784 			WARN((shift + width) > prev_shift,
785 				"%s has feature overlap at shift %d\n",
786 				ftr_reg->name, shift);
787 		}
788 
789 		/*
790 		 * Skip the first register. There is nothing to
791 		 * compare against for now.
792 		 */
793 		if (i == 0)
794 			continue;
795 		/*
796 		 * Registers here must be sorted in ascending order with respect
797 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
798 		 * to work correctly.
799 		 */
800 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
801 	}
802 }
803 
804 /*
805  * Initialise the CPU feature register from Boot CPU values.
806  * Also initiliases the strict_mask for the register.
807  * Any bits that are not covered by an arm64_ftr_bits entry are considered
808  * RES0 for the system-wide value, and must strictly match.
809  */
810 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
811 {
812 	u64 val = 0;
813 	u64 strict_mask = ~0x0ULL;
814 	u64 user_mask = 0;
815 	u64 valid_mask = 0;
816 
817 	const struct arm64_ftr_bits *ftrp;
818 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
819 
820 	if (!reg)
821 		return;
822 
823 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
824 		u64 ftr_mask = arm64_ftr_mask(ftrp);
825 		s64 ftr_new = arm64_ftr_value(ftrp, new);
826 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
827 
828 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
829 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
830 			char *str = NULL;
831 
832 			if (ftr_ovr != tmp) {
833 				/* Unsafe, remove the override */
834 				reg->override->mask &= ~ftr_mask;
835 				reg->override->val &= ~ftr_mask;
836 				tmp = ftr_ovr;
837 				str = "ignoring override";
838 			} else if (ftr_new != tmp) {
839 				/* Override was valid */
840 				ftr_new = tmp;
841 				str = "forced";
842 			} else if (ftr_ovr == tmp) {
843 				/* Override was the safe value */
844 				str = "already set";
845 			}
846 
847 			if (str)
848 				pr_warn("%s[%d:%d]: %s to %llx\n",
849 					reg->name,
850 					ftrp->shift + ftrp->width - 1,
851 					ftrp->shift, str, tmp);
852 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
853 			reg->override->val &= ~ftr_mask;
854 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
855 				reg->name,
856 				ftrp->shift + ftrp->width - 1,
857 				ftrp->shift);
858 		}
859 
860 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
861 
862 		valid_mask |= ftr_mask;
863 		if (!ftrp->strict)
864 			strict_mask &= ~ftr_mask;
865 		if (ftrp->visible)
866 			user_mask |= ftr_mask;
867 		else
868 			reg->user_val = arm64_ftr_set_value(ftrp,
869 							    reg->user_val,
870 							    ftrp->safe_val);
871 	}
872 
873 	val &= valid_mask;
874 
875 	reg->sys_val = val;
876 	reg->strict_mask = strict_mask;
877 	reg->user_mask = user_mask;
878 }
879 
880 extern const struct arm64_cpu_capabilities arm64_errata[];
881 static const struct arm64_cpu_capabilities arm64_features[];
882 
883 static void __init
884 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
885 {
886 	for (; caps->matches; caps++) {
887 		if (WARN(caps->capability >= ARM64_NCAPS,
888 			"Invalid capability %d\n", caps->capability))
889 			continue;
890 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
891 			"Duplicate entry for capability %d\n",
892 			caps->capability))
893 			continue;
894 		cpu_hwcaps_ptrs[caps->capability] = caps;
895 	}
896 }
897 
898 static void __init init_cpu_hwcaps_indirect_list(void)
899 {
900 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
901 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
902 }
903 
904 static void __init setup_boot_cpu_capabilities(void);
905 
906 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
907 {
908 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
909 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
910 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
911 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
912 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
913 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
914 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
915 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
916 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
917 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
918 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
919 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
920 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
921 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
922 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
923 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
924 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
925 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
926 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
927 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
928 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
929 }
930 
931 void __init init_cpu_features(struct cpuinfo_arm64 *info)
932 {
933 	/* Before we start using the tables, make sure it is sorted */
934 	sort_ftr_regs();
935 
936 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
937 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
938 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
939 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
940 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
941 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
942 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
943 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
944 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
945 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
946 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
947 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
948 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
949 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
950 
951 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
952 		init_32bit_cpu_features(&info->aarch32);
953 
954 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
955 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
956 		vec_init_vq_map(ARM64_VEC_SVE);
957 	}
958 
959 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
960 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
961 
962 	/*
963 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
964 	 * before we handle the boot CPU below.
965 	 */
966 	init_cpu_hwcaps_indirect_list();
967 
968 	/*
969 	 * Detect and enable early CPU capabilities based on the boot CPU,
970 	 * after we have initialised the CPU feature infrastructure.
971 	 */
972 	setup_boot_cpu_capabilities();
973 }
974 
975 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
976 {
977 	const struct arm64_ftr_bits *ftrp;
978 
979 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
980 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
981 		s64 ftr_new = arm64_ftr_value(ftrp, new);
982 
983 		if (ftr_cur == ftr_new)
984 			continue;
985 		/* Find a safe value */
986 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
987 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
988 	}
989 
990 }
991 
992 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
993 {
994 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
995 
996 	if (!regp)
997 		return 0;
998 
999 	update_cpu_ftr_reg(regp, val);
1000 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
1001 		return 0;
1002 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
1003 			regp->name, boot, cpu, val);
1004 	return 1;
1005 }
1006 
1007 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1008 {
1009 	const struct arm64_ftr_bits *ftrp;
1010 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1011 
1012 	if (!regp)
1013 		return;
1014 
1015 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1016 		if (ftrp->shift == field) {
1017 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1018 			break;
1019 		}
1020 	}
1021 
1022 	/* Bogus field? */
1023 	WARN_ON(!ftrp->width);
1024 }
1025 
1026 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1027 					 struct cpuinfo_arm64 *boot)
1028 {
1029 	static bool boot_cpu_32bit_regs_overridden = false;
1030 
1031 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1032 		return;
1033 
1034 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1035 		return;
1036 
1037 	boot->aarch32 = info->aarch32;
1038 	init_32bit_cpu_features(&boot->aarch32);
1039 	boot_cpu_32bit_regs_overridden = true;
1040 }
1041 
1042 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1043 				     struct cpuinfo_32bit *boot)
1044 {
1045 	int taint = 0;
1046 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1047 
1048 	/*
1049 	 * If we don't have AArch32 at EL1, then relax the strictness of
1050 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1051 	 */
1052 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1053 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1054 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1055 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1056 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1057 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1058 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1059 	}
1060 
1061 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1062 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1063 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1064 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1065 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1066 				      info->reg_id_isar0, boot->reg_id_isar0);
1067 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1068 				      info->reg_id_isar1, boot->reg_id_isar1);
1069 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1070 				      info->reg_id_isar2, boot->reg_id_isar2);
1071 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1072 				      info->reg_id_isar3, boot->reg_id_isar3);
1073 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1074 				      info->reg_id_isar4, boot->reg_id_isar4);
1075 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1076 				      info->reg_id_isar5, boot->reg_id_isar5);
1077 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1078 				      info->reg_id_isar6, boot->reg_id_isar6);
1079 
1080 	/*
1081 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1082 	 * ACTLR formats could differ across CPUs and therefore would have to
1083 	 * be trapped for virtualization anyway.
1084 	 */
1085 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1086 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1087 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1088 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1089 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1090 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1091 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1092 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1093 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1094 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1095 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1096 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1097 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1098 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1099 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1100 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1101 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1102 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1103 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1104 				      info->reg_mvfr0, boot->reg_mvfr0);
1105 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1106 				      info->reg_mvfr1, boot->reg_mvfr1);
1107 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1108 				      info->reg_mvfr2, boot->reg_mvfr2);
1109 
1110 	return taint;
1111 }
1112 
1113 /*
1114  * Update system wide CPU feature registers with the values from a
1115  * non-boot CPU. Also performs SANITY checks to make sure that there
1116  * aren't any insane variations from that of the boot CPU.
1117  */
1118 void update_cpu_features(int cpu,
1119 			 struct cpuinfo_arm64 *info,
1120 			 struct cpuinfo_arm64 *boot)
1121 {
1122 	int taint = 0;
1123 
1124 	/*
1125 	 * The kernel can handle differing I-cache policies, but otherwise
1126 	 * caches should look identical. Userspace JITs will make use of
1127 	 * *minLine.
1128 	 */
1129 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1130 				      info->reg_ctr, boot->reg_ctr);
1131 
1132 	/*
1133 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1134 	 * could result in too much or too little memory being zeroed if a
1135 	 * process is preempted and migrated between CPUs.
1136 	 */
1137 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1138 				      info->reg_dczid, boot->reg_dczid);
1139 
1140 	/* If different, timekeeping will be broken (especially with KVM) */
1141 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1142 				      info->reg_cntfrq, boot->reg_cntfrq);
1143 
1144 	/*
1145 	 * The kernel uses self-hosted debug features and expects CPUs to
1146 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1147 	 * and BRPs to be identical.
1148 	 * ID_AA64DFR1 is currently RES0.
1149 	 */
1150 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1151 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1152 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1153 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1154 	/*
1155 	 * Even in big.LITTLE, processors should be identical instruction-set
1156 	 * wise.
1157 	 */
1158 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1159 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1160 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1161 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1162 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1163 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1164 
1165 	/*
1166 	 * Differing PARange support is fine as long as all peripherals and
1167 	 * memory are mapped within the minimum PARange of all CPUs.
1168 	 * Linux should not care about secure memory.
1169 	 */
1170 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1171 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1172 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1173 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1174 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1175 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1176 
1177 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1178 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1179 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1180 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1181 
1182 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1183 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1184 
1185 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1186 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1187 					info->reg_zcr, boot->reg_zcr);
1188 
1189 		/* Probe vector lengths, unless we already gave up on SVE */
1190 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1191 		    !system_capabilities_finalized())
1192 			vec_update_vq_map(ARM64_VEC_SVE);
1193 	}
1194 
1195 	/*
1196 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1197 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1198 	 * value is the same on all CPUs.
1199 	 */
1200 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1201 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1202 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1203 					      info->reg_gmid, boot->reg_gmid);
1204 	}
1205 
1206 	/*
1207 	 * If we don't have AArch32 at all then skip the checks entirely
1208 	 * as the register values may be UNKNOWN and we're not going to be
1209 	 * using them for anything.
1210 	 *
1211 	 * This relies on a sanitised view of the AArch64 ID registers
1212 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1213 	 */
1214 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1215 		lazy_init_32bit_cpu_features(info, boot);
1216 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1217 						   &boot->aarch32);
1218 	}
1219 
1220 	/*
1221 	 * Mismatched CPU features are a recipe for disaster. Don't even
1222 	 * pretend to support them.
1223 	 */
1224 	if (taint) {
1225 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1226 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1227 	}
1228 }
1229 
1230 u64 read_sanitised_ftr_reg(u32 id)
1231 {
1232 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1233 
1234 	if (!regp)
1235 		return 0;
1236 	return regp->sys_val;
1237 }
1238 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1239 
1240 #define read_sysreg_case(r)	\
1241 	case r:		val = read_sysreg_s(r); break;
1242 
1243 /*
1244  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1245  * Read the system register on the current CPU
1246  */
1247 u64 __read_sysreg_by_encoding(u32 sys_id)
1248 {
1249 	struct arm64_ftr_reg *regp;
1250 	u64 val;
1251 
1252 	switch (sys_id) {
1253 	read_sysreg_case(SYS_ID_PFR0_EL1);
1254 	read_sysreg_case(SYS_ID_PFR1_EL1);
1255 	read_sysreg_case(SYS_ID_PFR2_EL1);
1256 	read_sysreg_case(SYS_ID_DFR0_EL1);
1257 	read_sysreg_case(SYS_ID_DFR1_EL1);
1258 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1259 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1260 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1261 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1262 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1263 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1264 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1265 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1266 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1267 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1268 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1269 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1270 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1271 	read_sysreg_case(SYS_MVFR0_EL1);
1272 	read_sysreg_case(SYS_MVFR1_EL1);
1273 	read_sysreg_case(SYS_MVFR2_EL1);
1274 
1275 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1276 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1277 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1278 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1279 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1280 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1281 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1282 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1283 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1284 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1285 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1286 
1287 	read_sysreg_case(SYS_CNTFRQ_EL0);
1288 	read_sysreg_case(SYS_CTR_EL0);
1289 	read_sysreg_case(SYS_DCZID_EL0);
1290 
1291 	default:
1292 		BUG();
1293 		return 0;
1294 	}
1295 
1296 	regp  = get_arm64_ftr_reg(sys_id);
1297 	if (regp) {
1298 		val &= ~regp->override->mask;
1299 		val |= (regp->override->val & regp->override->mask);
1300 	}
1301 
1302 	return val;
1303 }
1304 
1305 #include <linux/irqchip/arm-gic-v3.h>
1306 
1307 static bool
1308 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1309 {
1310 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1311 
1312 	return val >= entry->min_field_value;
1313 }
1314 
1315 static bool
1316 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1317 {
1318 	u64 val;
1319 
1320 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1321 	if (scope == SCOPE_SYSTEM)
1322 		val = read_sanitised_ftr_reg(entry->sys_reg);
1323 	else
1324 		val = __read_sysreg_by_encoding(entry->sys_reg);
1325 
1326 	return feature_matches(val, entry);
1327 }
1328 
1329 const struct cpumask *system_32bit_el0_cpumask(void)
1330 {
1331 	if (!system_supports_32bit_el0())
1332 		return cpu_none_mask;
1333 
1334 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1335 		return cpu_32bit_el0_mask;
1336 
1337 	return cpu_possible_mask;
1338 }
1339 
1340 static int __init parse_32bit_el0_param(char *str)
1341 {
1342 	allow_mismatched_32bit_el0 = true;
1343 	return 0;
1344 }
1345 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1346 
1347 static ssize_t aarch32_el0_show(struct device *dev,
1348 				struct device_attribute *attr, char *buf)
1349 {
1350 	const struct cpumask *mask = system_32bit_el0_cpumask();
1351 
1352 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1353 }
1354 static const DEVICE_ATTR_RO(aarch32_el0);
1355 
1356 static int __init aarch32_el0_sysfs_init(void)
1357 {
1358 	if (!allow_mismatched_32bit_el0)
1359 		return 0;
1360 
1361 	return device_create_file(cpu_subsys.dev_root, &dev_attr_aarch32_el0);
1362 }
1363 device_initcall(aarch32_el0_sysfs_init);
1364 
1365 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1366 {
1367 	if (!has_cpuid_feature(entry, scope))
1368 		return allow_mismatched_32bit_el0;
1369 
1370 	if (scope == SCOPE_SYSTEM)
1371 		pr_info("detected: 32-bit EL0 Support\n");
1372 
1373 	return true;
1374 }
1375 
1376 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1377 {
1378 	bool has_sre;
1379 
1380 	if (!has_cpuid_feature(entry, scope))
1381 		return false;
1382 
1383 	has_sre = gic_enable_sre();
1384 	if (!has_sre)
1385 		pr_warn_once("%s present but disabled by higher exception level\n",
1386 			     entry->desc);
1387 
1388 	return has_sre;
1389 }
1390 
1391 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1392 {
1393 	u32 midr = read_cpuid_id();
1394 
1395 	/* Cavium ThunderX pass 1.x and 2.x */
1396 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1397 		MIDR_CPU_VAR_REV(0, 0),
1398 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1399 }
1400 
1401 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1402 {
1403 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1404 
1405 	return cpuid_feature_extract_signed_field(pfr0,
1406 					ID_AA64PFR0_FP_SHIFT) < 0;
1407 }
1408 
1409 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1410 			  int scope)
1411 {
1412 	u64 ctr;
1413 
1414 	if (scope == SCOPE_SYSTEM)
1415 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1416 	else
1417 		ctr = read_cpuid_effective_cachetype();
1418 
1419 	return ctr & BIT(CTR_IDC_SHIFT);
1420 }
1421 
1422 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1423 {
1424 	/*
1425 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1426 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1427 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1428 	 * value.
1429 	 */
1430 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1431 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1432 }
1433 
1434 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1435 			  int scope)
1436 {
1437 	u64 ctr;
1438 
1439 	if (scope == SCOPE_SYSTEM)
1440 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1441 	else
1442 		ctr = read_cpuid_cachetype();
1443 
1444 	return ctr & BIT(CTR_DIC_SHIFT);
1445 }
1446 
1447 static bool __maybe_unused
1448 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1449 {
1450 	/*
1451 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1452 	 * may share TLB entries with a CPU stuck in the crashed
1453 	 * kernel.
1454 	 */
1455 	if (is_kdump_kernel())
1456 		return false;
1457 
1458 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1459 		return false;
1460 
1461 	return has_cpuid_feature(entry, scope);
1462 }
1463 
1464 /*
1465  * This check is triggered during the early boot before the cpufeature
1466  * is initialised. Checking the status on the local CPU allows the boot
1467  * CPU to detect the need for non-global mappings and thus avoiding a
1468  * pagetable re-write after all the CPUs are booted. This check will be
1469  * anyway run on individual CPUs, allowing us to get the consistent
1470  * state once the SMP CPUs are up and thus make the switch to non-global
1471  * mappings if required.
1472  */
1473 bool kaslr_requires_kpti(void)
1474 {
1475 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1476 		return false;
1477 
1478 	/*
1479 	 * E0PD does a similar job to KPTI so can be used instead
1480 	 * where available.
1481 	 */
1482 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1483 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1484 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1485 						ID_AA64MMFR2_E0PD_SHIFT))
1486 			return false;
1487 	}
1488 
1489 	/*
1490 	 * Systems affected by Cavium erratum 24756 are incompatible
1491 	 * with KPTI.
1492 	 */
1493 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1494 		extern const struct midr_range cavium_erratum_27456_cpus[];
1495 
1496 		if (is_midr_in_range_list(read_cpuid_id(),
1497 					  cavium_erratum_27456_cpus))
1498 			return false;
1499 	}
1500 
1501 	return kaslr_offset() > 0;
1502 }
1503 
1504 static bool __meltdown_safe = true;
1505 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1506 
1507 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1508 				int scope)
1509 {
1510 	/* List of CPUs that are not vulnerable and don't need KPTI */
1511 	static const struct midr_range kpti_safe_list[] = {
1512 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1513 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1514 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1515 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1516 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1517 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1518 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1519 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1520 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1521 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1522 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1523 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1524 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1525 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1526 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1527 		{ /* sentinel */ }
1528 	};
1529 	char const *str = "kpti command line option";
1530 	bool meltdown_safe;
1531 
1532 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1533 
1534 	/* Defer to CPU feature registers */
1535 	if (has_cpuid_feature(entry, scope))
1536 		meltdown_safe = true;
1537 
1538 	if (!meltdown_safe)
1539 		__meltdown_safe = false;
1540 
1541 	/*
1542 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1543 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1544 	 * ends as well as you might imagine. Don't even try. We cannot rely
1545 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1546 	 * because cpucap detection order may change. However, since we know
1547 	 * affected CPUs are always in a homogeneous configuration, it is
1548 	 * safe to rely on this_cpu_has_cap() here.
1549 	 */
1550 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1551 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1552 		__kpti_forced = -1;
1553 	}
1554 
1555 	/* Useful for KASLR robustness */
1556 	if (kaslr_requires_kpti()) {
1557 		if (!__kpti_forced) {
1558 			str = "KASLR";
1559 			__kpti_forced = 1;
1560 		}
1561 	}
1562 
1563 	if (cpu_mitigations_off() && !__kpti_forced) {
1564 		str = "mitigations=off";
1565 		__kpti_forced = -1;
1566 	}
1567 
1568 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1569 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1570 		return false;
1571 	}
1572 
1573 	/* Forced? */
1574 	if (__kpti_forced) {
1575 		pr_info_once("kernel page table isolation forced %s by %s\n",
1576 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1577 		return __kpti_forced > 0;
1578 	}
1579 
1580 	return !meltdown_safe;
1581 }
1582 
1583 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1584 static void __nocfi
1585 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1586 {
1587 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1588 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1589 	kpti_remap_fn *remap_fn;
1590 
1591 	int cpu = smp_processor_id();
1592 
1593 	/*
1594 	 * We don't need to rewrite the page-tables if either we've done
1595 	 * it already or we have KASLR enabled and therefore have not
1596 	 * created any global mappings at all.
1597 	 */
1598 	if (arm64_use_ng_mappings)
1599 		return;
1600 
1601 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1602 
1603 	cpu_install_idmap();
1604 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1605 	cpu_uninstall_idmap();
1606 
1607 	if (!cpu)
1608 		arm64_use_ng_mappings = true;
1609 }
1610 #else
1611 static void
1612 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1613 {
1614 }
1615 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1616 
1617 static int __init parse_kpti(char *str)
1618 {
1619 	bool enabled;
1620 	int ret = strtobool(str, &enabled);
1621 
1622 	if (ret)
1623 		return ret;
1624 
1625 	__kpti_forced = enabled ? 1 : -1;
1626 	return 0;
1627 }
1628 early_param("kpti", parse_kpti);
1629 
1630 #ifdef CONFIG_ARM64_HW_AFDBM
1631 static inline void __cpu_enable_hw_dbm(void)
1632 {
1633 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1634 
1635 	write_sysreg(tcr, tcr_el1);
1636 	isb();
1637 	local_flush_tlb_all();
1638 }
1639 
1640 static bool cpu_has_broken_dbm(void)
1641 {
1642 	/* List of CPUs which have broken DBM support. */
1643 	static const struct midr_range cpus[] = {
1644 #ifdef CONFIG_ARM64_ERRATUM_1024718
1645 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1646 		/* Kryo4xx Silver (rdpe => r1p0) */
1647 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1648 #endif
1649 #ifdef CONFIG_ARM64_ERRATUM_2051678
1650 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1651 #endif
1652 		{},
1653 	};
1654 
1655 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1656 }
1657 
1658 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1659 {
1660 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1661 	       !cpu_has_broken_dbm();
1662 }
1663 
1664 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1665 {
1666 	if (cpu_can_use_dbm(cap))
1667 		__cpu_enable_hw_dbm();
1668 }
1669 
1670 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1671 		       int __unused)
1672 {
1673 	static bool detected = false;
1674 	/*
1675 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1676 	 * run a mix of CPUs with and without the feature. So, we
1677 	 * unconditionally enable the capability to allow any late CPU
1678 	 * to use the feature. We only enable the control bits on the
1679 	 * CPU, if it actually supports.
1680 	 *
1681 	 * We have to make sure we print the "feature" detection only
1682 	 * when at least one CPU actually uses it. So check if this CPU
1683 	 * can actually use it and print the message exactly once.
1684 	 *
1685 	 * This is safe as all CPUs (including secondary CPUs - due to the
1686 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1687 	 * goes through the "matches" check exactly once. Also if a CPU
1688 	 * matches the criteria, it is guaranteed that the CPU will turn
1689 	 * the DBM on, as the capability is unconditionally enabled.
1690 	 */
1691 	if (!detected && cpu_can_use_dbm(cap)) {
1692 		detected = true;
1693 		pr_info("detected: Hardware dirty bit management\n");
1694 	}
1695 
1696 	return true;
1697 }
1698 
1699 #endif
1700 
1701 #ifdef CONFIG_ARM64_AMU_EXTN
1702 
1703 /*
1704  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1705  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1706  * information regarding all the events that it supports. When a CPU bit is
1707  * set in the cpumask, the user of this feature can only rely on the presence
1708  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1709  * counters are enabled or access to these counters is enabled by code
1710  * executed at higher exception levels (firmware).
1711  */
1712 static struct cpumask amu_cpus __read_mostly;
1713 
1714 bool cpu_has_amu_feat(int cpu)
1715 {
1716 	return cpumask_test_cpu(cpu, &amu_cpus);
1717 }
1718 
1719 int get_cpu_with_amu_feat(void)
1720 {
1721 	return cpumask_any(&amu_cpus);
1722 }
1723 
1724 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1725 {
1726 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1727 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1728 			smp_processor_id());
1729 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1730 		update_freq_counters_refs();
1731 	}
1732 }
1733 
1734 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1735 		    int __unused)
1736 {
1737 	/*
1738 	 * The AMU extension is a non-conflicting feature: the kernel can
1739 	 * safely run a mix of CPUs with and without support for the
1740 	 * activity monitors extension. Therefore, unconditionally enable
1741 	 * the capability to allow any late CPU to use the feature.
1742 	 *
1743 	 * With this feature unconditionally enabled, the cpu_enable
1744 	 * function will be called for all CPUs that match the criteria,
1745 	 * including secondary and hotplugged, marking this feature as
1746 	 * present on that respective CPU. The enable function will also
1747 	 * print a detection message.
1748 	 */
1749 
1750 	return true;
1751 }
1752 #else
1753 int get_cpu_with_amu_feat(void)
1754 {
1755 	return nr_cpu_ids;
1756 }
1757 #endif
1758 
1759 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1760 {
1761 	return is_kernel_in_hyp_mode();
1762 }
1763 
1764 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1765 {
1766 	/*
1767 	 * Copy register values that aren't redirected by hardware.
1768 	 *
1769 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1770 	 * this value to tpidr_el2 before we patch the code. Once we've done
1771 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1772 	 * do anything here.
1773 	 */
1774 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1775 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1776 }
1777 
1778 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1779 {
1780 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1781 
1782 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1783 	WARN_ON(CLIDR_LOUU(val) || CLIDR_LOUIS(val));
1784 }
1785 
1786 #ifdef CONFIG_ARM64_PAN
1787 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1788 {
1789 	/*
1790 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1791 	 * is discarded once we return from the exception.
1792 	 */
1793 	WARN_ON_ONCE(in_interrupt());
1794 
1795 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1796 	set_pstate_pan(1);
1797 }
1798 #endif /* CONFIG_ARM64_PAN */
1799 
1800 #ifdef CONFIG_ARM64_RAS_EXTN
1801 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1802 {
1803 	/* Firmware may have left a deferred SError in this register. */
1804 	write_sysreg_s(0, SYS_DISR_EL1);
1805 }
1806 #endif /* CONFIG_ARM64_RAS_EXTN */
1807 
1808 #ifdef CONFIG_ARM64_PTR_AUTH
1809 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1810 {
1811 	int boot_val, sec_val;
1812 
1813 	/* We don't expect to be called with SCOPE_SYSTEM */
1814 	WARN_ON(scope == SCOPE_SYSTEM);
1815 	/*
1816 	 * The ptr-auth feature levels are not intercompatible with lower
1817 	 * levels. Hence we must match ptr-auth feature level of the secondary
1818 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1819 	 * from the sanitised register whereas direct register read is done for
1820 	 * the secondary CPUs.
1821 	 * The sanitised feature state is guaranteed to match that of the
1822 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1823 	 * a chance to update the state, with the capability.
1824 	 */
1825 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1826 					       entry->field_pos, entry->sign);
1827 	if (scope & SCOPE_BOOT_CPU)
1828 		return boot_val >= entry->min_field_value;
1829 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1830 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1831 					      entry->field_pos, entry->sign);
1832 	return sec_val == boot_val;
1833 }
1834 
1835 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1836 				     int scope)
1837 {
1838 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1839 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1840 }
1841 
1842 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1843 			     int __unused)
1844 {
1845 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1846 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1847 }
1848 #endif /* CONFIG_ARM64_PTR_AUTH */
1849 
1850 #ifdef CONFIG_ARM64_E0PD
1851 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1852 {
1853 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1854 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1855 }
1856 #endif /* CONFIG_ARM64_E0PD */
1857 
1858 #ifdef CONFIG_ARM64_PSEUDO_NMI
1859 static bool enable_pseudo_nmi;
1860 
1861 static int __init early_enable_pseudo_nmi(char *p)
1862 {
1863 	return strtobool(p, &enable_pseudo_nmi);
1864 }
1865 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1866 
1867 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1868 				   int scope)
1869 {
1870 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1871 }
1872 #endif
1873 
1874 #ifdef CONFIG_ARM64_BTI
1875 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1876 {
1877 	/*
1878 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1879 	 * function entry points using BR is a requirement for
1880 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1881 	 * So, be strict and forbid other BRs using other registers to
1882 	 * jump onto a PACIxSP instruction:
1883 	 */
1884 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1885 	isb();
1886 }
1887 #endif /* CONFIG_ARM64_BTI */
1888 
1889 #ifdef CONFIG_ARM64_MTE
1890 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1891 {
1892 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
1893 	isb();
1894 
1895 	/*
1896 	 * Clear the tags in the zero page. This needs to be done via the
1897 	 * linear map which has the Tagged attribute.
1898 	 */
1899 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1900 		mte_clear_page_tags(lm_alias(empty_zero_page));
1901 
1902 	kasan_init_hw_tags_cpu();
1903 }
1904 #endif /* CONFIG_ARM64_MTE */
1905 
1906 #ifdef CONFIG_KVM
1907 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1908 {
1909 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1910 		return false;
1911 
1912 	if (is_kernel_in_hyp_mode()) {
1913 		pr_warn("Protected KVM not available with VHE\n");
1914 		return false;
1915 	}
1916 
1917 	return true;
1918 }
1919 #endif /* CONFIG_KVM */
1920 
1921 /* Internal helper functions to match cpu capability type */
1922 static bool
1923 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1924 {
1925 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1926 }
1927 
1928 static bool
1929 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1930 {
1931 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1932 }
1933 
1934 static bool
1935 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1936 {
1937 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1938 }
1939 
1940 static const struct arm64_cpu_capabilities arm64_features[] = {
1941 	{
1942 		.desc = "GIC system register CPU interface",
1943 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1944 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1945 		.matches = has_useable_gicv3_cpuif,
1946 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1947 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1948 		.sign = FTR_UNSIGNED,
1949 		.min_field_value = 1,
1950 	},
1951 	{
1952 		.desc = "Enhanced Counter Virtualization",
1953 		.capability = ARM64_HAS_ECV,
1954 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1955 		.matches = has_cpuid_feature,
1956 		.sys_reg = SYS_ID_AA64MMFR0_EL1,
1957 		.field_pos = ID_AA64MMFR0_ECV_SHIFT,
1958 		.sign = FTR_UNSIGNED,
1959 		.min_field_value = 1,
1960 	},
1961 #ifdef CONFIG_ARM64_PAN
1962 	{
1963 		.desc = "Privileged Access Never",
1964 		.capability = ARM64_HAS_PAN,
1965 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1966 		.matches = has_cpuid_feature,
1967 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1968 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1969 		.sign = FTR_UNSIGNED,
1970 		.min_field_value = 1,
1971 		.cpu_enable = cpu_enable_pan,
1972 	},
1973 #endif /* CONFIG_ARM64_PAN */
1974 #ifdef CONFIG_ARM64_EPAN
1975 	{
1976 		.desc = "Enhanced Privileged Access Never",
1977 		.capability = ARM64_HAS_EPAN,
1978 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1979 		.matches = has_cpuid_feature,
1980 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1981 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1982 		.sign = FTR_UNSIGNED,
1983 		.min_field_value = 3,
1984 	},
1985 #endif /* CONFIG_ARM64_EPAN */
1986 #ifdef CONFIG_ARM64_LSE_ATOMICS
1987 	{
1988 		.desc = "LSE atomic instructions",
1989 		.capability = ARM64_HAS_LSE_ATOMICS,
1990 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1991 		.matches = has_cpuid_feature,
1992 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1993 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1994 		.sign = FTR_UNSIGNED,
1995 		.min_field_value = 2,
1996 	},
1997 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1998 	{
1999 		.desc = "Software prefetching using PRFM",
2000 		.capability = ARM64_HAS_NO_HW_PREFETCH,
2001 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2002 		.matches = has_no_hw_prefetch,
2003 	},
2004 	{
2005 		.desc = "Virtualization Host Extensions",
2006 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
2007 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2008 		.matches = runs_at_el2,
2009 		.cpu_enable = cpu_copy_el2regs,
2010 	},
2011 	{
2012 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2013 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2014 		.matches = has_32bit_el0,
2015 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2016 		.sign = FTR_UNSIGNED,
2017 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
2018 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2019 	},
2020 #ifdef CONFIG_KVM
2021 	{
2022 		.desc = "32-bit EL1 Support",
2023 		.capability = ARM64_HAS_32BIT_EL1,
2024 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2025 		.matches = has_cpuid_feature,
2026 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2027 		.sign = FTR_UNSIGNED,
2028 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
2029 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2030 	},
2031 	{
2032 		.desc = "Protected KVM",
2033 		.capability = ARM64_KVM_PROTECTED_MODE,
2034 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2035 		.matches = is_kvm_protected_mode,
2036 	},
2037 #endif
2038 	{
2039 		.desc = "Kernel page table isolation (KPTI)",
2040 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2041 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2042 		/*
2043 		 * The ID feature fields below are used to indicate that
2044 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2045 		 * more details.
2046 		 */
2047 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2048 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
2049 		.min_field_value = 1,
2050 		.matches = unmap_kernel_at_el0,
2051 		.cpu_enable = kpti_install_ng_mappings,
2052 	},
2053 	{
2054 		/* FP/SIMD is not implemented */
2055 		.capability = ARM64_HAS_NO_FPSIMD,
2056 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2057 		.min_field_value = 0,
2058 		.matches = has_no_fpsimd,
2059 	},
2060 #ifdef CONFIG_ARM64_PMEM
2061 	{
2062 		.desc = "Data cache clean to Point of Persistence",
2063 		.capability = ARM64_HAS_DCPOP,
2064 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2065 		.matches = has_cpuid_feature,
2066 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2067 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2068 		.min_field_value = 1,
2069 	},
2070 	{
2071 		.desc = "Data cache clean to Point of Deep Persistence",
2072 		.capability = ARM64_HAS_DCPODP,
2073 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2074 		.matches = has_cpuid_feature,
2075 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2076 		.sign = FTR_UNSIGNED,
2077 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2078 		.min_field_value = 2,
2079 	},
2080 #endif
2081 #ifdef CONFIG_ARM64_SVE
2082 	{
2083 		.desc = "Scalable Vector Extension",
2084 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2085 		.capability = ARM64_SVE,
2086 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2087 		.sign = FTR_UNSIGNED,
2088 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2089 		.min_field_value = ID_AA64PFR0_SVE,
2090 		.matches = has_cpuid_feature,
2091 		.cpu_enable = sve_kernel_enable,
2092 	},
2093 #endif /* CONFIG_ARM64_SVE */
2094 #ifdef CONFIG_ARM64_RAS_EXTN
2095 	{
2096 		.desc = "RAS Extension Support",
2097 		.capability = ARM64_HAS_RAS_EXTN,
2098 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2099 		.matches = has_cpuid_feature,
2100 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2101 		.sign = FTR_UNSIGNED,
2102 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2103 		.min_field_value = ID_AA64PFR0_RAS_V1,
2104 		.cpu_enable = cpu_clear_disr,
2105 	},
2106 #endif /* CONFIG_ARM64_RAS_EXTN */
2107 #ifdef CONFIG_ARM64_AMU_EXTN
2108 	{
2109 		/*
2110 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2111 		 * Therefore, don't provide .desc as we don't want the detection
2112 		 * message to be shown until at least one CPU is detected to
2113 		 * support the feature.
2114 		 */
2115 		.capability = ARM64_HAS_AMU_EXTN,
2116 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2117 		.matches = has_amu,
2118 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2119 		.sign = FTR_UNSIGNED,
2120 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2121 		.min_field_value = ID_AA64PFR0_AMU,
2122 		.cpu_enable = cpu_amu_enable,
2123 	},
2124 #endif /* CONFIG_ARM64_AMU_EXTN */
2125 	{
2126 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2127 		.capability = ARM64_HAS_CACHE_IDC,
2128 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2129 		.matches = has_cache_idc,
2130 		.cpu_enable = cpu_emulate_effective_ctr,
2131 	},
2132 	{
2133 		.desc = "Instruction cache invalidation not required for I/D coherence",
2134 		.capability = ARM64_HAS_CACHE_DIC,
2135 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2136 		.matches = has_cache_dic,
2137 	},
2138 	{
2139 		.desc = "Stage-2 Force Write-Back",
2140 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2141 		.capability = ARM64_HAS_STAGE2_FWB,
2142 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2143 		.sign = FTR_UNSIGNED,
2144 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2145 		.min_field_value = 1,
2146 		.matches = has_cpuid_feature,
2147 		.cpu_enable = cpu_has_fwb,
2148 	},
2149 	{
2150 		.desc = "ARMv8.4 Translation Table Level",
2151 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2152 		.capability = ARM64_HAS_ARMv8_4_TTL,
2153 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2154 		.sign = FTR_UNSIGNED,
2155 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2156 		.min_field_value = 1,
2157 		.matches = has_cpuid_feature,
2158 	},
2159 	{
2160 		.desc = "TLB range maintenance instructions",
2161 		.capability = ARM64_HAS_TLB_RANGE,
2162 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2163 		.matches = has_cpuid_feature,
2164 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2165 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
2166 		.sign = FTR_UNSIGNED,
2167 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
2168 	},
2169 #ifdef CONFIG_ARM64_HW_AFDBM
2170 	{
2171 		/*
2172 		 * Since we turn this on always, we don't want the user to
2173 		 * think that the feature is available when it may not be.
2174 		 * So hide the description.
2175 		 *
2176 		 * .desc = "Hardware pagetable Dirty Bit Management",
2177 		 *
2178 		 */
2179 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2180 		.capability = ARM64_HW_DBM,
2181 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2182 		.sign = FTR_UNSIGNED,
2183 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2184 		.min_field_value = 2,
2185 		.matches = has_hw_dbm,
2186 		.cpu_enable = cpu_enable_hw_dbm,
2187 	},
2188 #endif
2189 	{
2190 		.desc = "CRC32 instructions",
2191 		.capability = ARM64_HAS_CRC32,
2192 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2193 		.matches = has_cpuid_feature,
2194 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2195 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2196 		.min_field_value = 1,
2197 	},
2198 	{
2199 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2200 		.capability = ARM64_SSBS,
2201 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2202 		.matches = has_cpuid_feature,
2203 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2204 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2205 		.sign = FTR_UNSIGNED,
2206 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2207 	},
2208 #ifdef CONFIG_ARM64_CNP
2209 	{
2210 		.desc = "Common not Private translations",
2211 		.capability = ARM64_HAS_CNP,
2212 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2213 		.matches = has_useable_cnp,
2214 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2215 		.sign = FTR_UNSIGNED,
2216 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2217 		.min_field_value = 1,
2218 		.cpu_enable = cpu_enable_cnp,
2219 	},
2220 #endif
2221 	{
2222 		.desc = "Speculation barrier (SB)",
2223 		.capability = ARM64_HAS_SB,
2224 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2225 		.matches = has_cpuid_feature,
2226 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2227 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2228 		.sign = FTR_UNSIGNED,
2229 		.min_field_value = 1,
2230 	},
2231 #ifdef CONFIG_ARM64_PTR_AUTH
2232 	{
2233 		.desc = "Address authentication (architected algorithm)",
2234 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2235 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2236 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2237 		.sign = FTR_UNSIGNED,
2238 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2239 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2240 		.matches = has_address_auth_cpucap,
2241 	},
2242 	{
2243 		.desc = "Address authentication (IMP DEF algorithm)",
2244 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2245 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2246 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2247 		.sign = FTR_UNSIGNED,
2248 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2249 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2250 		.matches = has_address_auth_cpucap,
2251 	},
2252 	{
2253 		.capability = ARM64_HAS_ADDRESS_AUTH,
2254 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2255 		.matches = has_address_auth_metacap,
2256 	},
2257 	{
2258 		.desc = "Generic authentication (architected algorithm)",
2259 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2260 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2261 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2262 		.sign = FTR_UNSIGNED,
2263 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2264 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2265 		.matches = has_cpuid_feature,
2266 	},
2267 	{
2268 		.desc = "Generic authentication (IMP DEF algorithm)",
2269 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2270 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2271 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2272 		.sign = FTR_UNSIGNED,
2273 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2274 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2275 		.matches = has_cpuid_feature,
2276 	},
2277 	{
2278 		.capability = ARM64_HAS_GENERIC_AUTH,
2279 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2280 		.matches = has_generic_auth,
2281 	},
2282 #endif /* CONFIG_ARM64_PTR_AUTH */
2283 #ifdef CONFIG_ARM64_PSEUDO_NMI
2284 	{
2285 		/*
2286 		 * Depends on having GICv3
2287 		 */
2288 		.desc = "IRQ priority masking",
2289 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2290 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2291 		.matches = can_use_gic_priorities,
2292 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2293 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2294 		.sign = FTR_UNSIGNED,
2295 		.min_field_value = 1,
2296 	},
2297 #endif
2298 #ifdef CONFIG_ARM64_E0PD
2299 	{
2300 		.desc = "E0PD",
2301 		.capability = ARM64_HAS_E0PD,
2302 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2303 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2304 		.sign = FTR_UNSIGNED,
2305 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2306 		.matches = has_cpuid_feature,
2307 		.min_field_value = 1,
2308 		.cpu_enable = cpu_enable_e0pd,
2309 	},
2310 #endif
2311 #ifdef CONFIG_ARCH_RANDOM
2312 	{
2313 		.desc = "Random Number Generator",
2314 		.capability = ARM64_HAS_RNG,
2315 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2316 		.matches = has_cpuid_feature,
2317 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2318 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2319 		.sign = FTR_UNSIGNED,
2320 		.min_field_value = 1,
2321 	},
2322 #endif
2323 #ifdef CONFIG_ARM64_BTI
2324 	{
2325 		.desc = "Branch Target Identification",
2326 		.capability = ARM64_BTI,
2327 #ifdef CONFIG_ARM64_BTI_KERNEL
2328 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2329 #else
2330 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2331 #endif
2332 		.matches = has_cpuid_feature,
2333 		.cpu_enable = bti_enable,
2334 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2335 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2336 		.min_field_value = ID_AA64PFR1_BT_BTI,
2337 		.sign = FTR_UNSIGNED,
2338 	},
2339 #endif
2340 #ifdef CONFIG_ARM64_MTE
2341 	{
2342 		.desc = "Memory Tagging Extension",
2343 		.capability = ARM64_MTE,
2344 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2345 		.matches = has_cpuid_feature,
2346 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2347 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2348 		.min_field_value = ID_AA64PFR1_MTE,
2349 		.sign = FTR_UNSIGNED,
2350 		.cpu_enable = cpu_enable_mte,
2351 	},
2352 	{
2353 		.desc = "Asymmetric MTE Tag Check Fault",
2354 		.capability = ARM64_MTE_ASYMM,
2355 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2356 		.matches = has_cpuid_feature,
2357 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2358 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2359 		.min_field_value = ID_AA64PFR1_MTE_ASYMM,
2360 		.sign = FTR_UNSIGNED,
2361 	},
2362 #endif /* CONFIG_ARM64_MTE */
2363 	{
2364 		.desc = "RCpc load-acquire (LDAPR)",
2365 		.capability = ARM64_HAS_LDAPR,
2366 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2367 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2368 		.sign = FTR_UNSIGNED,
2369 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2370 		.matches = has_cpuid_feature,
2371 		.min_field_value = 1,
2372 	},
2373 	{},
2374 };
2375 
2376 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2377 		.matches = has_cpuid_feature,					\
2378 		.sys_reg = reg,							\
2379 		.field_pos = field,						\
2380 		.sign = s,							\
2381 		.min_field_value = min_value,
2382 
2383 #define __HWCAP_CAP(name, cap_type, cap)					\
2384 		.desc = name,							\
2385 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2386 		.hwcap_type = cap_type,						\
2387 		.hwcap = cap,							\
2388 
2389 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2390 	{									\
2391 		__HWCAP_CAP(#cap, cap_type, cap)				\
2392 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2393 	}
2394 
2395 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2396 	{									\
2397 		__HWCAP_CAP(#cap, cap_type, cap)				\
2398 		.matches = cpucap_multi_entry_cap_matches,			\
2399 		.match_list = list,						\
2400 	}
2401 
2402 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2403 	{									\
2404 		__HWCAP_CAP(#cap, cap_type, cap)				\
2405 		.matches = match,						\
2406 	}
2407 
2408 #ifdef CONFIG_ARM64_PTR_AUTH
2409 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2410 	{
2411 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2412 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2413 	},
2414 	{
2415 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2416 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2417 	},
2418 	{},
2419 };
2420 
2421 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2422 	{
2423 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2424 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2425 	},
2426 	{
2427 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2428 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2429 	},
2430 	{},
2431 };
2432 #endif
2433 
2434 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2435 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2436 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2437 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2438 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2439 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2440 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2441 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2442 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2443 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2444 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2445 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2446 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2447 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2448 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2449 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2450 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2451 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2452 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2453 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2454 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2455 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2456 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2457 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2458 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2459 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2460 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2461 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2462 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2463 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2464 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2465 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2466 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2467 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2468 #ifdef CONFIG_ARM64_SVE
2469 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2470 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2471 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2472 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2473 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2474 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2475 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2476 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2477 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2478 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2479 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2480 #endif
2481 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2482 #ifdef CONFIG_ARM64_BTI
2483 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2484 #endif
2485 #ifdef CONFIG_ARM64_PTR_AUTH
2486 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2487 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2488 #endif
2489 #ifdef CONFIG_ARM64_MTE
2490 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2491 #endif /* CONFIG_ARM64_MTE */
2492 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2493 	HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
2494 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2495 	{},
2496 };
2497 
2498 #ifdef CONFIG_COMPAT
2499 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2500 {
2501 	/*
2502 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2503 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2504 	 * check is future proof, by making sure value is non-zero.
2505 	 */
2506 	u32 mvfr1;
2507 
2508 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2509 	if (scope == SCOPE_SYSTEM)
2510 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2511 	else
2512 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2513 
2514 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2515 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2516 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2517 }
2518 #endif
2519 
2520 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2521 #ifdef CONFIG_COMPAT
2522 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2523 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2524 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2525 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2526 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2527 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2528 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2529 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2530 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2531 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2532 #endif
2533 	{},
2534 };
2535 
2536 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2537 {
2538 	switch (cap->hwcap_type) {
2539 	case CAP_HWCAP:
2540 		cpu_set_feature(cap->hwcap);
2541 		break;
2542 #ifdef CONFIG_COMPAT
2543 	case CAP_COMPAT_HWCAP:
2544 		compat_elf_hwcap |= (u32)cap->hwcap;
2545 		break;
2546 	case CAP_COMPAT_HWCAP2:
2547 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2548 		break;
2549 #endif
2550 	default:
2551 		WARN_ON(1);
2552 		break;
2553 	}
2554 }
2555 
2556 /* Check if we have a particular HWCAP enabled */
2557 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2558 {
2559 	bool rc;
2560 
2561 	switch (cap->hwcap_type) {
2562 	case CAP_HWCAP:
2563 		rc = cpu_have_feature(cap->hwcap);
2564 		break;
2565 #ifdef CONFIG_COMPAT
2566 	case CAP_COMPAT_HWCAP:
2567 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2568 		break;
2569 	case CAP_COMPAT_HWCAP2:
2570 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2571 		break;
2572 #endif
2573 	default:
2574 		WARN_ON(1);
2575 		rc = false;
2576 	}
2577 
2578 	return rc;
2579 }
2580 
2581 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2582 {
2583 	/* We support emulation of accesses to CPU ID feature registers */
2584 	cpu_set_named_feature(CPUID);
2585 	for (; hwcaps->matches; hwcaps++)
2586 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2587 			cap_set_elf_hwcap(hwcaps);
2588 }
2589 
2590 static void update_cpu_capabilities(u16 scope_mask)
2591 {
2592 	int i;
2593 	const struct arm64_cpu_capabilities *caps;
2594 
2595 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2596 	for (i = 0; i < ARM64_NCAPS; i++) {
2597 		caps = cpu_hwcaps_ptrs[i];
2598 		if (!caps || !(caps->type & scope_mask) ||
2599 		    cpus_have_cap(caps->capability) ||
2600 		    !caps->matches(caps, cpucap_default_scope(caps)))
2601 			continue;
2602 
2603 		if (caps->desc)
2604 			pr_info("detected: %s\n", caps->desc);
2605 		cpus_set_cap(caps->capability);
2606 
2607 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2608 			set_bit(caps->capability, boot_capabilities);
2609 	}
2610 }
2611 
2612 /*
2613  * Enable all the available capabilities on this CPU. The capabilities
2614  * with BOOT_CPU scope are handled separately and hence skipped here.
2615  */
2616 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2617 {
2618 	int i;
2619 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2620 
2621 	for_each_available_cap(i) {
2622 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2623 
2624 		if (WARN_ON(!cap))
2625 			continue;
2626 
2627 		if (!(cap->type & non_boot_scope))
2628 			continue;
2629 
2630 		if (cap->cpu_enable)
2631 			cap->cpu_enable(cap);
2632 	}
2633 	return 0;
2634 }
2635 
2636 /*
2637  * Run through the enabled capabilities and enable() it on all active
2638  * CPUs
2639  */
2640 static void __init enable_cpu_capabilities(u16 scope_mask)
2641 {
2642 	int i;
2643 	const struct arm64_cpu_capabilities *caps;
2644 	bool boot_scope;
2645 
2646 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2647 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2648 
2649 	for (i = 0; i < ARM64_NCAPS; i++) {
2650 		unsigned int num;
2651 
2652 		caps = cpu_hwcaps_ptrs[i];
2653 		if (!caps || !(caps->type & scope_mask))
2654 			continue;
2655 		num = caps->capability;
2656 		if (!cpus_have_cap(num))
2657 			continue;
2658 
2659 		/* Ensure cpus_have_const_cap(num) works */
2660 		static_branch_enable(&cpu_hwcap_keys[num]);
2661 
2662 		if (boot_scope && caps->cpu_enable)
2663 			/*
2664 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2665 			 * before any secondary CPU boots. Thus, each secondary
2666 			 * will enable the capability as appropriate via
2667 			 * check_local_cpu_capabilities(). The only exception is
2668 			 * the boot CPU, for which the capability must be
2669 			 * enabled here. This approach avoids costly
2670 			 * stop_machine() calls for this case.
2671 			 */
2672 			caps->cpu_enable(caps);
2673 	}
2674 
2675 	/*
2676 	 * For all non-boot scope capabilities, use stop_machine()
2677 	 * as it schedules the work allowing us to modify PSTATE,
2678 	 * instead of on_each_cpu() which uses an IPI, giving us a
2679 	 * PSTATE that disappears when we return.
2680 	 */
2681 	if (!boot_scope)
2682 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2683 			     NULL, cpu_online_mask);
2684 }
2685 
2686 /*
2687  * Run through the list of capabilities to check for conflicts.
2688  * If the system has already detected a capability, take necessary
2689  * action on this CPU.
2690  */
2691 static void verify_local_cpu_caps(u16 scope_mask)
2692 {
2693 	int i;
2694 	bool cpu_has_cap, system_has_cap;
2695 	const struct arm64_cpu_capabilities *caps;
2696 
2697 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2698 
2699 	for (i = 0; i < ARM64_NCAPS; i++) {
2700 		caps = cpu_hwcaps_ptrs[i];
2701 		if (!caps || !(caps->type & scope_mask))
2702 			continue;
2703 
2704 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2705 		system_has_cap = cpus_have_cap(caps->capability);
2706 
2707 		if (system_has_cap) {
2708 			/*
2709 			 * Check if the new CPU misses an advertised feature,
2710 			 * which is not safe to miss.
2711 			 */
2712 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2713 				break;
2714 			/*
2715 			 * We have to issue cpu_enable() irrespective of
2716 			 * whether the CPU has it or not, as it is enabeld
2717 			 * system wide. It is upto the call back to take
2718 			 * appropriate action on this CPU.
2719 			 */
2720 			if (caps->cpu_enable)
2721 				caps->cpu_enable(caps);
2722 		} else {
2723 			/*
2724 			 * Check if the CPU has this capability if it isn't
2725 			 * safe to have when the system doesn't.
2726 			 */
2727 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2728 				break;
2729 		}
2730 	}
2731 
2732 	if (i < ARM64_NCAPS) {
2733 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2734 			smp_processor_id(), caps->capability,
2735 			caps->desc, system_has_cap, cpu_has_cap);
2736 
2737 		if (cpucap_panic_on_conflict(caps))
2738 			cpu_panic_kernel();
2739 		else
2740 			cpu_die_early();
2741 	}
2742 }
2743 
2744 /*
2745  * Check for CPU features that are used in early boot
2746  * based on the Boot CPU value.
2747  */
2748 static void check_early_cpu_features(void)
2749 {
2750 	verify_cpu_asid_bits();
2751 
2752 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2753 }
2754 
2755 static void
2756 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2757 {
2758 
2759 	for (; caps->matches; caps++)
2760 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2761 			pr_crit("CPU%d: missing HWCAP: %s\n",
2762 					smp_processor_id(), caps->desc);
2763 			cpu_die_early();
2764 		}
2765 }
2766 
2767 static void verify_local_elf_hwcaps(void)
2768 {
2769 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2770 
2771 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2772 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2773 }
2774 
2775 static void verify_sve_features(void)
2776 {
2777 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2778 	u64 zcr = read_zcr_features();
2779 
2780 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2781 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2782 
2783 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SVE)) {
2784 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2785 			smp_processor_id());
2786 		cpu_die_early();
2787 	}
2788 
2789 	/* Add checks on other ZCR bits here if necessary */
2790 }
2791 
2792 static void verify_hyp_capabilities(void)
2793 {
2794 	u64 safe_mmfr1, mmfr0, mmfr1;
2795 	int parange, ipa_max;
2796 	unsigned int safe_vmid_bits, vmid_bits;
2797 
2798 	if (!IS_ENABLED(CONFIG_KVM))
2799 		return;
2800 
2801 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2802 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2803 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2804 
2805 	/* Verify VMID bits */
2806 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2807 	vmid_bits = get_vmid_bits(mmfr1);
2808 	if (vmid_bits < safe_vmid_bits) {
2809 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2810 		cpu_die_early();
2811 	}
2812 
2813 	/* Verify IPA range */
2814 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2815 				ID_AA64MMFR0_PARANGE_SHIFT);
2816 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2817 	if (ipa_max < get_kvm_ipa_limit()) {
2818 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2819 		cpu_die_early();
2820 	}
2821 }
2822 
2823 /*
2824  * Run through the enabled system capabilities and enable() it on this CPU.
2825  * The capabilities were decided based on the available CPUs at the boot time.
2826  * Any new CPU should match the system wide status of the capability. If the
2827  * new CPU doesn't have a capability which the system now has enabled, we
2828  * cannot do anything to fix it up and could cause unexpected failures. So
2829  * we park the CPU.
2830  */
2831 static void verify_local_cpu_capabilities(void)
2832 {
2833 	/*
2834 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2835 	 * check_early_cpu_features(), as they need to be verified
2836 	 * on all secondary CPUs.
2837 	 */
2838 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2839 	verify_local_elf_hwcaps();
2840 
2841 	if (system_supports_sve())
2842 		verify_sve_features();
2843 
2844 	if (is_hyp_mode_available())
2845 		verify_hyp_capabilities();
2846 }
2847 
2848 void check_local_cpu_capabilities(void)
2849 {
2850 	/*
2851 	 * All secondary CPUs should conform to the early CPU features
2852 	 * in use by the kernel based on boot CPU.
2853 	 */
2854 	check_early_cpu_features();
2855 
2856 	/*
2857 	 * If we haven't finalised the system capabilities, this CPU gets
2858 	 * a chance to update the errata work arounds and local features.
2859 	 * Otherwise, this CPU should verify that it has all the system
2860 	 * advertised capabilities.
2861 	 */
2862 	if (!system_capabilities_finalized())
2863 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2864 	else
2865 		verify_local_cpu_capabilities();
2866 }
2867 
2868 static void __init setup_boot_cpu_capabilities(void)
2869 {
2870 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2871 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2872 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2873 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2874 }
2875 
2876 bool this_cpu_has_cap(unsigned int n)
2877 {
2878 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2879 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2880 
2881 		if (cap)
2882 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2883 	}
2884 
2885 	return false;
2886 }
2887 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
2888 
2889 /*
2890  * This helper function is used in a narrow window when,
2891  * - The system wide safe registers are set with all the SMP CPUs and,
2892  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2893  * In all other cases cpus_have_{const_}cap() should be used.
2894  */
2895 static bool __maybe_unused __system_matches_cap(unsigned int n)
2896 {
2897 	if (n < ARM64_NCAPS) {
2898 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2899 
2900 		if (cap)
2901 			return cap->matches(cap, SCOPE_SYSTEM);
2902 	}
2903 	return false;
2904 }
2905 
2906 void cpu_set_feature(unsigned int num)
2907 {
2908 	WARN_ON(num >= MAX_CPU_FEATURES);
2909 	elf_hwcap |= BIT(num);
2910 }
2911 EXPORT_SYMBOL_GPL(cpu_set_feature);
2912 
2913 bool cpu_have_feature(unsigned int num)
2914 {
2915 	WARN_ON(num >= MAX_CPU_FEATURES);
2916 	return elf_hwcap & BIT(num);
2917 }
2918 EXPORT_SYMBOL_GPL(cpu_have_feature);
2919 
2920 unsigned long cpu_get_elf_hwcap(void)
2921 {
2922 	/*
2923 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2924 	 * note that for userspace compatibility we guarantee that bits 62
2925 	 * and 63 will always be returned as 0.
2926 	 */
2927 	return lower_32_bits(elf_hwcap);
2928 }
2929 
2930 unsigned long cpu_get_elf_hwcap2(void)
2931 {
2932 	return upper_32_bits(elf_hwcap);
2933 }
2934 
2935 static void __init setup_system_capabilities(void)
2936 {
2937 	/*
2938 	 * We have finalised the system-wide safe feature
2939 	 * registers, finalise the capabilities that depend
2940 	 * on it. Also enable all the available capabilities,
2941 	 * that are not enabled already.
2942 	 */
2943 	update_cpu_capabilities(SCOPE_SYSTEM);
2944 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2945 }
2946 
2947 void __init setup_cpu_features(void)
2948 {
2949 	u32 cwg;
2950 
2951 	setup_system_capabilities();
2952 	setup_elf_hwcaps(arm64_elf_hwcaps);
2953 
2954 	if (system_supports_32bit_el0())
2955 		setup_elf_hwcaps(compat_elf_hwcaps);
2956 
2957 	if (system_uses_ttbr0_pan())
2958 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2959 
2960 	sve_setup();
2961 	minsigstksz_setup();
2962 
2963 	/* Advertise that we have computed the system capabilities */
2964 	finalize_system_capabilities();
2965 
2966 	/*
2967 	 * Check for sane CTR_EL0.CWG value.
2968 	 */
2969 	cwg = cache_type_cwg();
2970 	if (!cwg)
2971 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2972 			ARCH_DMA_MINALIGN);
2973 }
2974 
2975 static int enable_mismatched_32bit_el0(unsigned int cpu)
2976 {
2977 	/*
2978 	 * The first 32-bit-capable CPU we detected and so can no longer
2979 	 * be offlined by userspace. -1 indicates we haven't yet onlined
2980 	 * a 32-bit-capable CPU.
2981 	 */
2982 	static int lucky_winner = -1;
2983 
2984 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
2985 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
2986 
2987 	if (cpu_32bit) {
2988 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
2989 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
2990 	}
2991 
2992 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
2993 		return 0;
2994 
2995 	if (lucky_winner >= 0)
2996 		return 0;
2997 
2998 	/*
2999 	 * We've detected a mismatch. We need to keep one of our CPUs with
3000 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
3001 	 * every CPU in the system for a 32-bit task.
3002 	 */
3003 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
3004 							 cpu_active_mask);
3005 	get_cpu_device(lucky_winner)->offline_disabled = true;
3006 	setup_elf_hwcaps(compat_elf_hwcaps);
3007 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
3008 		cpu, lucky_winner);
3009 	return 0;
3010 }
3011 
3012 static int __init init_32bit_el0_mask(void)
3013 {
3014 	if (!allow_mismatched_32bit_el0)
3015 		return 0;
3016 
3017 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3018 		return -ENOMEM;
3019 
3020 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3021 				 "arm64/mismatched_32bit_el0:online",
3022 				 enable_mismatched_32bit_el0, NULL);
3023 }
3024 subsys_initcall_sync(init_32bit_el0_mask);
3025 
3026 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3027 {
3028 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
3029 }
3030 
3031 /*
3032  * We emulate only the following system register space.
3033  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
3034  * See Table C5-6 System instruction encodings for System register accesses,
3035  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3036  */
3037 static inline bool __attribute_const__ is_emulated(u32 id)
3038 {
3039 	return (sys_reg_Op0(id) == 0x3 &&
3040 		sys_reg_CRn(id) == 0x0 &&
3041 		sys_reg_Op1(id) == 0x0 &&
3042 		(sys_reg_CRm(id) == 0 ||
3043 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
3044 }
3045 
3046 /*
3047  * With CRm == 0, reg should be one of :
3048  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3049  */
3050 static inline int emulate_id_reg(u32 id, u64 *valp)
3051 {
3052 	switch (id) {
3053 	case SYS_MIDR_EL1:
3054 		*valp = read_cpuid_id();
3055 		break;
3056 	case SYS_MPIDR_EL1:
3057 		*valp = SYS_MPIDR_SAFE_VAL;
3058 		break;
3059 	case SYS_REVIDR_EL1:
3060 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3061 		*valp = 0;
3062 		break;
3063 	default:
3064 		return -EINVAL;
3065 	}
3066 
3067 	return 0;
3068 }
3069 
3070 static int emulate_sys_reg(u32 id, u64 *valp)
3071 {
3072 	struct arm64_ftr_reg *regp;
3073 
3074 	if (!is_emulated(id))
3075 		return -EINVAL;
3076 
3077 	if (sys_reg_CRm(id) == 0)
3078 		return emulate_id_reg(id, valp);
3079 
3080 	regp = get_arm64_ftr_reg_nowarn(id);
3081 	if (regp)
3082 		*valp = arm64_ftr_reg_user_value(regp);
3083 	else
3084 		/*
3085 		 * The untracked registers are either IMPLEMENTATION DEFINED
3086 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3087 		 */
3088 		*valp = 0;
3089 	return 0;
3090 }
3091 
3092 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3093 {
3094 	int rc;
3095 	u64 val;
3096 
3097 	rc = emulate_sys_reg(sys_reg, &val);
3098 	if (!rc) {
3099 		pt_regs_write_reg(regs, rt, val);
3100 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3101 	}
3102 	return rc;
3103 }
3104 
3105 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3106 {
3107 	u32 sys_reg, rt;
3108 
3109 	/*
3110 	 * sys_reg values are defined as used in mrs/msr instruction.
3111 	 * shift the imm value to get the encoding.
3112 	 */
3113 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3114 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3115 	return do_emulate_mrs(regs, sys_reg, rt);
3116 }
3117 
3118 static struct undef_hook mrs_hook = {
3119 	.instr_mask = 0xffff0000,
3120 	.instr_val  = 0xd5380000,
3121 	.pstate_mask = PSR_AA32_MODE_MASK,
3122 	.pstate_val = PSR_MODE_EL0t,
3123 	.fn = emulate_mrs,
3124 };
3125 
3126 static int __init enable_mrs_emulation(void)
3127 {
3128 	register_undef_hook(&mrs_hook);
3129 	return 0;
3130 }
3131 
3132 core_initcall(enable_mrs_emulation);
3133 
3134 enum mitigation_state arm64_get_meltdown_state(void)
3135 {
3136 	if (__meltdown_safe)
3137 		return SPECTRE_UNAFFECTED;
3138 
3139 	if (arm64_kernel_unmapped_at_el0())
3140 		return SPECTRE_MITIGATED;
3141 
3142 	return SPECTRE_VULNERABLE;
3143 }
3144 
3145 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3146 			  char *buf)
3147 {
3148 	switch (arm64_get_meltdown_state()) {
3149 	case SPECTRE_UNAFFECTED:
3150 		return sprintf(buf, "Not affected\n");
3151 
3152 	case SPECTRE_MITIGATED:
3153 		return sprintf(buf, "Mitigation: PTI\n");
3154 
3155 	default:
3156 		return sprintf(buf, "Vulnerable\n");
3157 	}
3158 }
3159