xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision 8047f98c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Contains CPU feature definitions
4  *
5  * Copyright (C) 2015 ARM Ltd.
6  *
7  * A note for the weary kernel hacker: the code here is confusing and hard to
8  * follow! That's partly because it's solving a nasty problem, but also because
9  * there's a little bit of over-abstraction that tends to obscure what's going
10  * on behind a maze of helper functions and macros.
11  *
12  * The basic problem is that hardware folks have started gluing together CPUs
13  * with distinct architectural features; in some cases even creating SoCs where
14  * user-visible instructions are available only on a subset of the available
15  * cores. We try to address this by snapshotting the feature registers of the
16  * boot CPU and comparing these with the feature registers of each secondary
17  * CPU when bringing them up. If there is a mismatch, then we update the
18  * snapshot state to indicate the lowest-common denominator of the feature,
19  * known as the "safe" value. This snapshot state can be queried to view the
20  * "sanitised" value of a feature register.
21  *
22  * The sanitised register values are used to decide which capabilities we
23  * have in the system. These may be in the form of traditional "hwcaps"
24  * advertised to userspace or internal "cpucaps" which are used to configure
25  * things like alternative patching and static keys. While a feature mismatch
26  * may result in a TAINT_CPU_OUT_OF_SPEC kernel taint, a capability mismatch
27  * may prevent a CPU from being onlined at all.
28  *
29  * Some implementation details worth remembering:
30  *
31  * - Mismatched features are *always* sanitised to a "safe" value, which
32  *   usually indicates that the feature is not supported.
33  *
34  * - A mismatched feature marked with FTR_STRICT will cause a "SANITY CHECK"
35  *   warning when onlining an offending CPU and the kernel will be tainted
36  *   with TAINT_CPU_OUT_OF_SPEC.
37  *
38  * - Features marked as FTR_VISIBLE have their sanitised value visible to
39  *   userspace. FTR_VISIBLE features in registers that are only visible
40  *   to EL0 by trapping *must* have a corresponding HWCAP so that late
41  *   onlining of CPUs cannot lead to features disappearing at runtime.
42  *
43  * - A "feature" is typically a 4-bit register field. A "capability" is the
44  *   high-level description derived from the sanitised field value.
45  *
46  * - Read the Arm ARM (DDI 0487F.a) section D13.1.3 ("Principles of the ID
47  *   scheme for fields in ID registers") to understand when feature fields
48  *   may be signed or unsigned (FTR_SIGNED and FTR_UNSIGNED accordingly).
49  *
50  * - KVM exposes its own view of the feature registers to guest operating
51  *   systems regardless of FTR_VISIBLE. This is typically driven from the
52  *   sanitised register values to allow virtual CPUs to be migrated between
53  *   arbitrary physical CPUs, but some features not present on the host are
54  *   also advertised and emulated. Look at sys_reg_descs[] for the gory
55  *   details.
56  *
57  * - If the arm64_ftr_bits[] for a register has a missing field, then this
58  *   field is treated as STRICT RES0, including for read_sanitised_ftr_reg().
59  *   This is stronger than FTR_HIDDEN and can be used to hide features from
60  *   KVM guests.
61  */
62 
63 #define pr_fmt(fmt) "CPU features: " fmt
64 
65 #include <linux/bsearch.h>
66 #include <linux/cpumask.h>
67 #include <linux/crash_dump.h>
68 #include <linux/sort.h>
69 #include <linux/stop_machine.h>
70 #include <linux/sysfs.h>
71 #include <linux/types.h>
72 #include <linux/minmax.h>
73 #include <linux/mm.h>
74 #include <linux/cpu.h>
75 #include <linux/kasan.h>
76 #include <linux/percpu.h>
77 
78 #include <asm/cpu.h>
79 #include <asm/cpufeature.h>
80 #include <asm/cpu_ops.h>
81 #include <asm/fpsimd.h>
82 #include <asm/insn.h>
83 #include <asm/kvm_host.h>
84 #include <asm/mmu_context.h>
85 #include <asm/mte.h>
86 #include <asm/processor.h>
87 #include <asm/smp.h>
88 #include <asm/sysreg.h>
89 #include <asm/traps.h>
90 #include <asm/vectors.h>
91 #include <asm/virt.h>
92 
93 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
94 static unsigned long elf_hwcap __read_mostly;
95 
96 #ifdef CONFIG_COMPAT
97 #define COMPAT_ELF_HWCAP_DEFAULT	\
98 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
99 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
100 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
101 				 COMPAT_HWCAP_LPAE)
102 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
103 unsigned int compat_elf_hwcap2 __read_mostly;
104 #endif
105 
106 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
107 EXPORT_SYMBOL(cpu_hwcaps);
108 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
109 
110 /* Need also bit for ARM64_CB_PATCH */
111 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
112 
113 bool arm64_use_ng_mappings = false;
114 EXPORT_SYMBOL(arm64_use_ng_mappings);
115 
116 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
117 
118 /*
119  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
120  * support it?
121  */
122 static bool __read_mostly allow_mismatched_32bit_el0;
123 
124 /*
125  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
126  * seen at least one CPU capable of 32-bit EL0.
127  */
128 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
129 
130 /*
131  * Mask of CPUs supporting 32-bit EL0.
132  * Only valid if arm64_mismatched_32bit_el0 is enabled.
133  */
134 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
135 
136 /*
137  * Flag to indicate if we have computed the system wide
138  * capabilities based on the boot time active CPUs. This
139  * will be used to determine if a new booting CPU should
140  * go through the verification process to make sure that it
141  * supports the system capabilities, without using a hotplug
142  * notifier. This is also used to decide if we could use
143  * the fast path for checking constant CPU caps.
144  */
145 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
146 EXPORT_SYMBOL(arm64_const_caps_ready);
147 static inline void finalize_system_capabilities(void)
148 {
149 	static_branch_enable(&arm64_const_caps_ready);
150 }
151 
152 void dump_cpu_features(void)
153 {
154 	/* file-wide pr_fmt adds "CPU features: " prefix */
155 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
156 }
157 
158 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
159 EXPORT_SYMBOL(cpu_hwcap_keys);
160 
161 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
162 	{						\
163 		.sign = SIGNED,				\
164 		.visible = VISIBLE,			\
165 		.strict = STRICT,			\
166 		.type = TYPE,				\
167 		.shift = SHIFT,				\
168 		.width = WIDTH,				\
169 		.safe_val = SAFE_VAL,			\
170 	}
171 
172 /* Define a feature with unsigned values */
173 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
174 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
175 
176 /* Define a feature with a signed value */
177 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
178 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
179 
180 #define ARM64_FTR_END					\
181 	{						\
182 		.width = 0,				\
183 	}
184 
185 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
186 
187 static bool __system_matches_cap(unsigned int n);
188 
189 /*
190  * NOTE: Any changes to the visibility of features should be kept in
191  * sync with the documentation of the CPU feature register ABI.
192  */
193 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
208 	ARM64_FTR_END,
209 };
210 
211 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
212 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
219 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
221 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
223 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
226 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
228 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
229 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
230 	ARM64_FTR_END,
231 };
232 
233 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
235 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
236 	ARM64_FTR_END,
237 };
238 
239 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
240 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
244 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
245 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
246 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
247 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
250 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
251 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
252 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
253 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
254 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
255 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
256 	ARM64_FTR_END,
257 };
258 
259 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
260 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
261 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
263 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
264 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
265 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
266 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
267 	ARM64_FTR_END,
268 };
269 
270 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
271 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
272 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
277 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
278 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
279 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
280 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
281 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
282 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
284 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
285 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
286 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
287 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
288 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
289 	ARM64_FTR_END,
290 };
291 
292 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
293 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
294 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
295 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
296 	/*
297 	 * Page size not being supported at Stage-2 is not fatal. You
298 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
299 	 * your favourite nesting hypervisor.
300 	 *
301 	 * There is a small corner case where the hypervisor explicitly
302 	 * advertises a given granule size at Stage-2 (value 2) on some
303 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
304 	 * vCPUs. Although this is not forbidden by the architecture, it
305 	 * indicates that the hypervisor is being silly (or buggy).
306 	 *
307 	 * We make no effort to cope with this and pretend that if these
308 	 * fields are inconsistent across vCPUs, then it isn't worth
309 	 * trying to bring KVM up.
310 	 */
311 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
312 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
313 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
314 	/*
315 	 * We already refuse to boot CPUs that don't support our configured
316 	 * page size, so we can only detect mismatches for a page size other
317 	 * than the one we're currently using. Unfortunately, SoCs like this
318 	 * exist in the wild so, even though we don't like it, we'll have to go
319 	 * along with it and treat them as non-strict.
320 	 */
321 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
322 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
324 
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
326 	/* Linux shouldn't care about secure memory */
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
330 	/*
331 	 * Differing PARange is fine as long as all peripherals and memory are mapped
332 	 * within the minimum PARange of all CPUs
333 	 */
334 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
335 	ARM64_FTR_END,
336 };
337 
338 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
339 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
347 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
350 	ARM64_FTR_END,
351 };
352 
353 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
354 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
356 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
357 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
358 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
360 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
361 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
362 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
363 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
364 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
365 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
367 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
368 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
369 	ARM64_FTR_END,
370 };
371 
372 static const struct arm64_ftr_bits ftr_ctr[] = {
373 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
374 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
375 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
376 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
377 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
378 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
379 	/*
380 	 * Linux can handle differing I-cache policies. Userspace JITs will
381 	 * make use of *minLine.
382 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
383 	 */
384 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
385 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
386 	ARM64_FTR_END,
387 };
388 
389 static struct arm64_ftr_override __ro_after_init no_override = { };
390 
391 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
392 	.name		= "SYS_CTR_EL0",
393 	.ftr_bits	= ftr_ctr,
394 	.override	= &no_override,
395 };
396 
397 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
398 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
402 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
403 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
404 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
405 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
406 	ARM64_FTR_END,
407 };
408 
409 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
410 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
411 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
412 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
415 	/*
416 	 * We can instantiate multiple PMU instances with different levels
417 	 * of support.
418 	 */
419 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
420 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
421 	ARM64_FTR_END,
422 };
423 
424 static const struct arm64_ftr_bits ftr_mvfr2[] = {
425 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
427 	ARM64_FTR_END,
428 };
429 
430 static const struct arm64_ftr_bits ftr_dczid[] = {
431 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
432 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
433 	ARM64_FTR_END,
434 };
435 
436 static const struct arm64_ftr_bits ftr_gmid[] = {
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, SYS_GMID_EL1_BS_SHIFT, 4, 0),
438 	ARM64_FTR_END,
439 };
440 
441 static const struct arm64_ftr_bits ftr_id_isar0[] = {
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
444 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
446 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
447 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
448 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
449 	ARM64_FTR_END,
450 };
451 
452 static const struct arm64_ftr_bits ftr_id_isar5[] = {
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
459 	ARM64_FTR_END,
460 };
461 
462 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
463 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
464 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
465 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
466 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
467 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
468 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
470 
471 	/*
472 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
473 	 * external abort on speculative read. It is safe to assume that an
474 	 * SError might be generated than it will not be. Hence it has been
475 	 * classified as FTR_HIGHER_SAFE.
476 	 */
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
478 	ARM64_FTR_END,
479 };
480 
481 static const struct arm64_ftr_bits ftr_id_isar4[] = {
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
484 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
485 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
486 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
487 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
489 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
490 	ARM64_FTR_END,
491 };
492 
493 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
495 	ARM64_FTR_END,
496 };
497 
498 static const struct arm64_ftr_bits ftr_id_isar6[] = {
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
501 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
503 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
504 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
505 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
506 	ARM64_FTR_END,
507 };
508 
509 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
516 	ARM64_FTR_END,
517 };
518 
519 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
521 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
522 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
523 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
524 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
525 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
526 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
528 	ARM64_FTR_END,
529 };
530 
531 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
532 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
533 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
534 	ARM64_FTR_END,
535 };
536 
537 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
538 	/* [31:28] TraceFilt */
539 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
541 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
542 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
543 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
544 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
545 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
546 	ARM64_FTR_END,
547 };
548 
549 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
550 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
551 	ARM64_FTR_END,
552 };
553 
554 static const struct arm64_ftr_bits ftr_zcr[] = {
555 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
556 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
557 	ARM64_FTR_END,
558 };
559 
560 /*
561  * Common ftr bits for a 32bit register with all hidden, strict
562  * attributes, with 4bit feature fields and a default safe value of
563  * 0. Covers the following 32bit registers:
564  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
565  */
566 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
568 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
569 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
570 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
571 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
572 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
573 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
574 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
575 	ARM64_FTR_END,
576 };
577 
578 /* Table for a single 32bit feature value */
579 static const struct arm64_ftr_bits ftr_single32[] = {
580 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
581 	ARM64_FTR_END,
582 };
583 
584 static const struct arm64_ftr_bits ftr_raz[] = {
585 	ARM64_FTR_END,
586 };
587 
588 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
589 		.sys_id = id,					\
590 		.reg = 	&(struct arm64_ftr_reg){		\
591 			.name = id_str,				\
592 			.override = (ovr),			\
593 			.ftr_bits = &((table)[0]),		\
594 	}}
595 
596 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
597 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
598 
599 #define ARM64_FTR_REG(id, table)		\
600 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
601 
602 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
603 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
604 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
605 
606 static const struct __ftr_reg_entry {
607 	u32			sys_id;
608 	struct arm64_ftr_reg 	*reg;
609 } arm64_ftr_regs[] = {
610 
611 	/* Op1 = 0, CRn = 0, CRm = 1 */
612 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
613 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
614 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
615 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
616 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
617 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
618 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
619 
620 	/* Op1 = 0, CRn = 0, CRm = 2 */
621 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
622 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
623 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
624 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
625 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
626 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
627 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
628 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
629 
630 	/* Op1 = 0, CRn = 0, CRm = 3 */
631 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
632 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
633 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
634 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
635 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
636 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
637 
638 	/* Op1 = 0, CRn = 0, CRm = 4 */
639 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
640 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
641 			       &id_aa64pfr1_override),
642 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
643 
644 	/* Op1 = 0, CRn = 0, CRm = 5 */
645 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
646 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
647 
648 	/* Op1 = 0, CRn = 0, CRm = 6 */
649 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
650 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
651 			       &id_aa64isar1_override),
652 	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
653 
654 	/* Op1 = 0, CRn = 0, CRm = 7 */
655 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
656 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
657 			       &id_aa64mmfr1_override),
658 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
659 
660 	/* Op1 = 0, CRn = 1, CRm = 2 */
661 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
662 
663 	/* Op1 = 1, CRn = 0, CRm = 0 */
664 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
665 
666 	/* Op1 = 3, CRn = 0, CRm = 0 */
667 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
668 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
669 
670 	/* Op1 = 3, CRn = 14, CRm = 0 */
671 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
672 };
673 
674 static int search_cmp_ftr_reg(const void *id, const void *regp)
675 {
676 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
677 }
678 
679 /*
680  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
681  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
682  * ascending order of sys_id, we use binary search to find a matching
683  * entry.
684  *
685  * returns - Upon success,  matching ftr_reg entry for id.
686  *         - NULL on failure. It is upto the caller to decide
687  *	     the impact of a failure.
688  */
689 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
690 {
691 	const struct __ftr_reg_entry *ret;
692 
693 	ret = bsearch((const void *)(unsigned long)sys_id,
694 			arm64_ftr_regs,
695 			ARRAY_SIZE(arm64_ftr_regs),
696 			sizeof(arm64_ftr_regs[0]),
697 			search_cmp_ftr_reg);
698 	if (ret)
699 		return ret->reg;
700 	return NULL;
701 }
702 
703 /*
704  * get_arm64_ftr_reg - Looks up a feature register entry using
705  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
706  *
707  * returns - Upon success,  matching ftr_reg entry for id.
708  *         - NULL on failure but with an WARN_ON().
709  */
710 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
711 {
712 	struct arm64_ftr_reg *reg;
713 
714 	reg = get_arm64_ftr_reg_nowarn(sys_id);
715 
716 	/*
717 	 * Requesting a non-existent register search is an error. Warn
718 	 * and let the caller handle it.
719 	 */
720 	WARN_ON(!reg);
721 	return reg;
722 }
723 
724 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
725 			       s64 ftr_val)
726 {
727 	u64 mask = arm64_ftr_mask(ftrp);
728 
729 	reg &= ~mask;
730 	reg |= (ftr_val << ftrp->shift) & mask;
731 	return reg;
732 }
733 
734 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
735 				s64 cur)
736 {
737 	s64 ret = 0;
738 
739 	switch (ftrp->type) {
740 	case FTR_EXACT:
741 		ret = ftrp->safe_val;
742 		break;
743 	case FTR_LOWER_SAFE:
744 		ret = min(new, cur);
745 		break;
746 	case FTR_HIGHER_OR_ZERO_SAFE:
747 		if (!cur || !new)
748 			break;
749 		fallthrough;
750 	case FTR_HIGHER_SAFE:
751 		ret = max(new, cur);
752 		break;
753 	default:
754 		BUG();
755 	}
756 
757 	return ret;
758 }
759 
760 static void __init sort_ftr_regs(void)
761 {
762 	unsigned int i;
763 
764 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
765 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
766 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
767 		unsigned int j = 0;
768 
769 		/*
770 		 * Features here must be sorted in descending order with respect
771 		 * to their shift values and should not overlap with each other.
772 		 */
773 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
774 			unsigned int width = ftr_reg->ftr_bits[j].width;
775 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
776 			unsigned int prev_shift;
777 
778 			WARN((shift  + width) > 64,
779 				"%s has invalid feature at shift %d\n",
780 				ftr_reg->name, shift);
781 
782 			/*
783 			 * Skip the first feature. There is nothing to
784 			 * compare against for now.
785 			 */
786 			if (j == 0)
787 				continue;
788 
789 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
790 			WARN((shift + width) > prev_shift,
791 				"%s has feature overlap at shift %d\n",
792 				ftr_reg->name, shift);
793 		}
794 
795 		/*
796 		 * Skip the first register. There is nothing to
797 		 * compare against for now.
798 		 */
799 		if (i == 0)
800 			continue;
801 		/*
802 		 * Registers here must be sorted in ascending order with respect
803 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
804 		 * to work correctly.
805 		 */
806 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
807 	}
808 }
809 
810 /*
811  * Initialise the CPU feature register from Boot CPU values.
812  * Also initiliases the strict_mask for the register.
813  * Any bits that are not covered by an arm64_ftr_bits entry are considered
814  * RES0 for the system-wide value, and must strictly match.
815  */
816 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
817 {
818 	u64 val = 0;
819 	u64 strict_mask = ~0x0ULL;
820 	u64 user_mask = 0;
821 	u64 valid_mask = 0;
822 
823 	const struct arm64_ftr_bits *ftrp;
824 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
825 
826 	if (!reg)
827 		return;
828 
829 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
830 		u64 ftr_mask = arm64_ftr_mask(ftrp);
831 		s64 ftr_new = arm64_ftr_value(ftrp, new);
832 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
833 
834 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
835 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
836 			char *str = NULL;
837 
838 			if (ftr_ovr != tmp) {
839 				/* Unsafe, remove the override */
840 				reg->override->mask &= ~ftr_mask;
841 				reg->override->val &= ~ftr_mask;
842 				tmp = ftr_ovr;
843 				str = "ignoring override";
844 			} else if (ftr_new != tmp) {
845 				/* Override was valid */
846 				ftr_new = tmp;
847 				str = "forced";
848 			} else if (ftr_ovr == tmp) {
849 				/* Override was the safe value */
850 				str = "already set";
851 			}
852 
853 			if (str)
854 				pr_warn("%s[%d:%d]: %s to %llx\n",
855 					reg->name,
856 					ftrp->shift + ftrp->width - 1,
857 					ftrp->shift, str, tmp);
858 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
859 			reg->override->val &= ~ftr_mask;
860 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
861 				reg->name,
862 				ftrp->shift + ftrp->width - 1,
863 				ftrp->shift);
864 		}
865 
866 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
867 
868 		valid_mask |= ftr_mask;
869 		if (!ftrp->strict)
870 			strict_mask &= ~ftr_mask;
871 		if (ftrp->visible)
872 			user_mask |= ftr_mask;
873 		else
874 			reg->user_val = arm64_ftr_set_value(ftrp,
875 							    reg->user_val,
876 							    ftrp->safe_val);
877 	}
878 
879 	val &= valid_mask;
880 
881 	reg->sys_val = val;
882 	reg->strict_mask = strict_mask;
883 	reg->user_mask = user_mask;
884 }
885 
886 extern const struct arm64_cpu_capabilities arm64_errata[];
887 static const struct arm64_cpu_capabilities arm64_features[];
888 
889 static void __init
890 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
891 {
892 	for (; caps->matches; caps++) {
893 		if (WARN(caps->capability >= ARM64_NCAPS,
894 			"Invalid capability %d\n", caps->capability))
895 			continue;
896 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
897 			"Duplicate entry for capability %d\n",
898 			caps->capability))
899 			continue;
900 		cpu_hwcaps_ptrs[caps->capability] = caps;
901 	}
902 }
903 
904 static void __init init_cpu_hwcaps_indirect_list(void)
905 {
906 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
907 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
908 }
909 
910 static void __init setup_boot_cpu_capabilities(void);
911 
912 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
913 {
914 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
915 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
916 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
917 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
918 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
919 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
920 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
921 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
922 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
923 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
924 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
925 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
926 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
927 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
928 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
929 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
930 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
931 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
932 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
933 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
934 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
935 }
936 
937 void __init init_cpu_features(struct cpuinfo_arm64 *info)
938 {
939 	/* Before we start using the tables, make sure it is sorted */
940 	sort_ftr_regs();
941 
942 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
943 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
944 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
945 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
946 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
947 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
948 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
949 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
950 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
951 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
952 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
953 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
954 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
955 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
956 
957 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
958 		init_32bit_cpu_features(&info->aarch32);
959 
960 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
961 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
962 		vec_init_vq_map(ARM64_VEC_SVE);
963 	}
964 
965 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
966 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
967 
968 	/*
969 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
970 	 * before we handle the boot CPU below.
971 	 */
972 	init_cpu_hwcaps_indirect_list();
973 
974 	/*
975 	 * Detect and enable early CPU capabilities based on the boot CPU,
976 	 * after we have initialised the CPU feature infrastructure.
977 	 */
978 	setup_boot_cpu_capabilities();
979 }
980 
981 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
982 {
983 	const struct arm64_ftr_bits *ftrp;
984 
985 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
986 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
987 		s64 ftr_new = arm64_ftr_value(ftrp, new);
988 
989 		if (ftr_cur == ftr_new)
990 			continue;
991 		/* Find a safe value */
992 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
993 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
994 	}
995 
996 }
997 
998 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
999 {
1000 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1001 
1002 	if (!regp)
1003 		return 0;
1004 
1005 	update_cpu_ftr_reg(regp, val);
1006 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
1007 		return 0;
1008 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
1009 			regp->name, boot, cpu, val);
1010 	return 1;
1011 }
1012 
1013 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1014 {
1015 	const struct arm64_ftr_bits *ftrp;
1016 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1017 
1018 	if (!regp)
1019 		return;
1020 
1021 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1022 		if (ftrp->shift == field) {
1023 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1024 			break;
1025 		}
1026 	}
1027 
1028 	/* Bogus field? */
1029 	WARN_ON(!ftrp->width);
1030 }
1031 
1032 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1033 					 struct cpuinfo_arm64 *boot)
1034 {
1035 	static bool boot_cpu_32bit_regs_overridden = false;
1036 
1037 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1038 		return;
1039 
1040 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1041 		return;
1042 
1043 	boot->aarch32 = info->aarch32;
1044 	init_32bit_cpu_features(&boot->aarch32);
1045 	boot_cpu_32bit_regs_overridden = true;
1046 }
1047 
1048 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1049 				     struct cpuinfo_32bit *boot)
1050 {
1051 	int taint = 0;
1052 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1053 
1054 	/*
1055 	 * If we don't have AArch32 at EL1, then relax the strictness of
1056 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1057 	 */
1058 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1059 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1060 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1061 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1062 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1063 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1064 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1065 	}
1066 
1067 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1068 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1069 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1070 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1071 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1072 				      info->reg_id_isar0, boot->reg_id_isar0);
1073 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1074 				      info->reg_id_isar1, boot->reg_id_isar1);
1075 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1076 				      info->reg_id_isar2, boot->reg_id_isar2);
1077 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1078 				      info->reg_id_isar3, boot->reg_id_isar3);
1079 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1080 				      info->reg_id_isar4, boot->reg_id_isar4);
1081 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1082 				      info->reg_id_isar5, boot->reg_id_isar5);
1083 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1084 				      info->reg_id_isar6, boot->reg_id_isar6);
1085 
1086 	/*
1087 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1088 	 * ACTLR formats could differ across CPUs and therefore would have to
1089 	 * be trapped for virtualization anyway.
1090 	 */
1091 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1092 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1093 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1094 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1095 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1096 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1097 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1098 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1099 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1100 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1101 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1102 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1103 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1104 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1105 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1106 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1107 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1108 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1109 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1110 				      info->reg_mvfr0, boot->reg_mvfr0);
1111 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1112 				      info->reg_mvfr1, boot->reg_mvfr1);
1113 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1114 				      info->reg_mvfr2, boot->reg_mvfr2);
1115 
1116 	return taint;
1117 }
1118 
1119 /*
1120  * Update system wide CPU feature registers with the values from a
1121  * non-boot CPU. Also performs SANITY checks to make sure that there
1122  * aren't any insane variations from that of the boot CPU.
1123  */
1124 void update_cpu_features(int cpu,
1125 			 struct cpuinfo_arm64 *info,
1126 			 struct cpuinfo_arm64 *boot)
1127 {
1128 	int taint = 0;
1129 
1130 	/*
1131 	 * The kernel can handle differing I-cache policies, but otherwise
1132 	 * caches should look identical. Userspace JITs will make use of
1133 	 * *minLine.
1134 	 */
1135 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1136 				      info->reg_ctr, boot->reg_ctr);
1137 
1138 	/*
1139 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1140 	 * could result in too much or too little memory being zeroed if a
1141 	 * process is preempted and migrated between CPUs.
1142 	 */
1143 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1144 				      info->reg_dczid, boot->reg_dczid);
1145 
1146 	/* If different, timekeeping will be broken (especially with KVM) */
1147 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1148 				      info->reg_cntfrq, boot->reg_cntfrq);
1149 
1150 	/*
1151 	 * The kernel uses self-hosted debug features and expects CPUs to
1152 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1153 	 * and BRPs to be identical.
1154 	 * ID_AA64DFR1 is currently RES0.
1155 	 */
1156 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1157 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1158 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1159 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1160 	/*
1161 	 * Even in big.LITTLE, processors should be identical instruction-set
1162 	 * wise.
1163 	 */
1164 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1165 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1166 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1167 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1168 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1169 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1170 
1171 	/*
1172 	 * Differing PARange support is fine as long as all peripherals and
1173 	 * memory are mapped within the minimum PARange of all CPUs.
1174 	 * Linux should not care about secure memory.
1175 	 */
1176 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1177 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1178 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1179 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1180 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1181 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1182 
1183 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1184 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1185 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1186 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1187 
1188 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1189 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1190 
1191 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1192 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1193 					info->reg_zcr, boot->reg_zcr);
1194 
1195 		/* Probe vector lengths, unless we already gave up on SVE */
1196 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1197 		    !system_capabilities_finalized())
1198 			vec_update_vq_map(ARM64_VEC_SVE);
1199 	}
1200 
1201 	/*
1202 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1203 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1204 	 * value is the same on all CPUs.
1205 	 */
1206 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1207 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1208 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1209 					      info->reg_gmid, boot->reg_gmid);
1210 	}
1211 
1212 	/*
1213 	 * If we don't have AArch32 at all then skip the checks entirely
1214 	 * as the register values may be UNKNOWN and we're not going to be
1215 	 * using them for anything.
1216 	 *
1217 	 * This relies on a sanitised view of the AArch64 ID registers
1218 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1219 	 */
1220 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1221 		lazy_init_32bit_cpu_features(info, boot);
1222 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1223 						   &boot->aarch32);
1224 	}
1225 
1226 	/*
1227 	 * Mismatched CPU features are a recipe for disaster. Don't even
1228 	 * pretend to support them.
1229 	 */
1230 	if (taint) {
1231 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1232 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1233 	}
1234 }
1235 
1236 u64 read_sanitised_ftr_reg(u32 id)
1237 {
1238 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1239 
1240 	if (!regp)
1241 		return 0;
1242 	return regp->sys_val;
1243 }
1244 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1245 
1246 #define read_sysreg_case(r)	\
1247 	case r:		val = read_sysreg_s(r); break;
1248 
1249 /*
1250  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1251  * Read the system register on the current CPU
1252  */
1253 u64 __read_sysreg_by_encoding(u32 sys_id)
1254 {
1255 	struct arm64_ftr_reg *regp;
1256 	u64 val;
1257 
1258 	switch (sys_id) {
1259 	read_sysreg_case(SYS_ID_PFR0_EL1);
1260 	read_sysreg_case(SYS_ID_PFR1_EL1);
1261 	read_sysreg_case(SYS_ID_PFR2_EL1);
1262 	read_sysreg_case(SYS_ID_DFR0_EL1);
1263 	read_sysreg_case(SYS_ID_DFR1_EL1);
1264 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1265 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1266 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1267 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1268 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1269 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1270 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1271 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1272 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1273 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1274 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1275 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1276 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1277 	read_sysreg_case(SYS_MVFR0_EL1);
1278 	read_sysreg_case(SYS_MVFR1_EL1);
1279 	read_sysreg_case(SYS_MVFR2_EL1);
1280 
1281 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1282 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1283 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1284 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1285 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1286 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1287 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1288 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1289 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1290 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1291 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1292 
1293 	read_sysreg_case(SYS_CNTFRQ_EL0);
1294 	read_sysreg_case(SYS_CTR_EL0);
1295 	read_sysreg_case(SYS_DCZID_EL0);
1296 
1297 	default:
1298 		BUG();
1299 		return 0;
1300 	}
1301 
1302 	regp  = get_arm64_ftr_reg(sys_id);
1303 	if (regp) {
1304 		val &= ~regp->override->mask;
1305 		val |= (regp->override->val & regp->override->mask);
1306 	}
1307 
1308 	return val;
1309 }
1310 
1311 #include <linux/irqchip/arm-gic-v3.h>
1312 
1313 static bool
1314 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1315 {
1316 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1317 
1318 	return val >= entry->min_field_value;
1319 }
1320 
1321 static bool
1322 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1323 {
1324 	u64 val;
1325 
1326 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1327 	if (scope == SCOPE_SYSTEM)
1328 		val = read_sanitised_ftr_reg(entry->sys_reg);
1329 	else
1330 		val = __read_sysreg_by_encoding(entry->sys_reg);
1331 
1332 	return feature_matches(val, entry);
1333 }
1334 
1335 const struct cpumask *system_32bit_el0_cpumask(void)
1336 {
1337 	if (!system_supports_32bit_el0())
1338 		return cpu_none_mask;
1339 
1340 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1341 		return cpu_32bit_el0_mask;
1342 
1343 	return cpu_possible_mask;
1344 }
1345 
1346 static int __init parse_32bit_el0_param(char *str)
1347 {
1348 	allow_mismatched_32bit_el0 = true;
1349 	return 0;
1350 }
1351 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1352 
1353 static ssize_t aarch32_el0_show(struct device *dev,
1354 				struct device_attribute *attr, char *buf)
1355 {
1356 	const struct cpumask *mask = system_32bit_el0_cpumask();
1357 
1358 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1359 }
1360 static const DEVICE_ATTR_RO(aarch32_el0);
1361 
1362 static int __init aarch32_el0_sysfs_init(void)
1363 {
1364 	if (!allow_mismatched_32bit_el0)
1365 		return 0;
1366 
1367 	return device_create_file(cpu_subsys.dev_root, &dev_attr_aarch32_el0);
1368 }
1369 device_initcall(aarch32_el0_sysfs_init);
1370 
1371 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1372 {
1373 	if (!has_cpuid_feature(entry, scope))
1374 		return allow_mismatched_32bit_el0;
1375 
1376 	if (scope == SCOPE_SYSTEM)
1377 		pr_info("detected: 32-bit EL0 Support\n");
1378 
1379 	return true;
1380 }
1381 
1382 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1383 {
1384 	bool has_sre;
1385 
1386 	if (!has_cpuid_feature(entry, scope))
1387 		return false;
1388 
1389 	has_sre = gic_enable_sre();
1390 	if (!has_sre)
1391 		pr_warn_once("%s present but disabled by higher exception level\n",
1392 			     entry->desc);
1393 
1394 	return has_sre;
1395 }
1396 
1397 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1398 {
1399 	u32 midr = read_cpuid_id();
1400 
1401 	/* Cavium ThunderX pass 1.x and 2.x */
1402 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1403 		MIDR_CPU_VAR_REV(0, 0),
1404 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1405 }
1406 
1407 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1408 {
1409 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1410 
1411 	return cpuid_feature_extract_signed_field(pfr0,
1412 					ID_AA64PFR0_FP_SHIFT) < 0;
1413 }
1414 
1415 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1416 			  int scope)
1417 {
1418 	u64 ctr;
1419 
1420 	if (scope == SCOPE_SYSTEM)
1421 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1422 	else
1423 		ctr = read_cpuid_effective_cachetype();
1424 
1425 	return ctr & BIT(CTR_IDC_SHIFT);
1426 }
1427 
1428 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1429 {
1430 	/*
1431 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1432 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1433 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1434 	 * value.
1435 	 */
1436 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1437 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1438 }
1439 
1440 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1441 			  int scope)
1442 {
1443 	u64 ctr;
1444 
1445 	if (scope == SCOPE_SYSTEM)
1446 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1447 	else
1448 		ctr = read_cpuid_cachetype();
1449 
1450 	return ctr & BIT(CTR_DIC_SHIFT);
1451 }
1452 
1453 static bool __maybe_unused
1454 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1455 {
1456 	/*
1457 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1458 	 * may share TLB entries with a CPU stuck in the crashed
1459 	 * kernel.
1460 	 */
1461 	if (is_kdump_kernel())
1462 		return false;
1463 
1464 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1465 		return false;
1466 
1467 	return has_cpuid_feature(entry, scope);
1468 }
1469 
1470 /*
1471  * This check is triggered during the early boot before the cpufeature
1472  * is initialised. Checking the status on the local CPU allows the boot
1473  * CPU to detect the need for non-global mappings and thus avoiding a
1474  * pagetable re-write after all the CPUs are booted. This check will be
1475  * anyway run on individual CPUs, allowing us to get the consistent
1476  * state once the SMP CPUs are up and thus make the switch to non-global
1477  * mappings if required.
1478  */
1479 bool kaslr_requires_kpti(void)
1480 {
1481 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1482 		return false;
1483 
1484 	/*
1485 	 * E0PD does a similar job to KPTI so can be used instead
1486 	 * where available.
1487 	 */
1488 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1489 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1490 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1491 						ID_AA64MMFR2_E0PD_SHIFT))
1492 			return false;
1493 	}
1494 
1495 	/*
1496 	 * Systems affected by Cavium erratum 24756 are incompatible
1497 	 * with KPTI.
1498 	 */
1499 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1500 		extern const struct midr_range cavium_erratum_27456_cpus[];
1501 
1502 		if (is_midr_in_range_list(read_cpuid_id(),
1503 					  cavium_erratum_27456_cpus))
1504 			return false;
1505 	}
1506 
1507 	return kaslr_offset() > 0;
1508 }
1509 
1510 static bool __meltdown_safe = true;
1511 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1512 
1513 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1514 				int scope)
1515 {
1516 	/* List of CPUs that are not vulnerable and don't need KPTI */
1517 	static const struct midr_range kpti_safe_list[] = {
1518 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1519 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1520 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1521 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1522 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1523 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1524 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1525 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1526 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1527 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1528 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1529 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1530 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1531 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1532 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1533 		{ /* sentinel */ }
1534 	};
1535 	char const *str = "kpti command line option";
1536 	bool meltdown_safe;
1537 
1538 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1539 
1540 	/* Defer to CPU feature registers */
1541 	if (has_cpuid_feature(entry, scope))
1542 		meltdown_safe = true;
1543 
1544 	if (!meltdown_safe)
1545 		__meltdown_safe = false;
1546 
1547 	/*
1548 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1549 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1550 	 * ends as well as you might imagine. Don't even try. We cannot rely
1551 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1552 	 * because cpucap detection order may change. However, since we know
1553 	 * affected CPUs are always in a homogeneous configuration, it is
1554 	 * safe to rely on this_cpu_has_cap() here.
1555 	 */
1556 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1557 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1558 		__kpti_forced = -1;
1559 	}
1560 
1561 	/* Useful for KASLR robustness */
1562 	if (kaslr_requires_kpti()) {
1563 		if (!__kpti_forced) {
1564 			str = "KASLR";
1565 			__kpti_forced = 1;
1566 		}
1567 	}
1568 
1569 	if (cpu_mitigations_off() && !__kpti_forced) {
1570 		str = "mitigations=off";
1571 		__kpti_forced = -1;
1572 	}
1573 
1574 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1575 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1576 		return false;
1577 	}
1578 
1579 	/* Forced? */
1580 	if (__kpti_forced) {
1581 		pr_info_once("kernel page table isolation forced %s by %s\n",
1582 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1583 		return __kpti_forced > 0;
1584 	}
1585 
1586 	return !meltdown_safe;
1587 }
1588 
1589 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1590 static void __nocfi
1591 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1592 {
1593 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1594 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1595 	kpti_remap_fn *remap_fn;
1596 
1597 	int cpu = smp_processor_id();
1598 
1599 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1600 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1601 
1602 		__this_cpu_write(this_cpu_vector, v);
1603 	}
1604 
1605 	/*
1606 	 * We don't need to rewrite the page-tables if either we've done
1607 	 * it already or we have KASLR enabled and therefore have not
1608 	 * created any global mappings at all.
1609 	 */
1610 	if (arm64_use_ng_mappings)
1611 		return;
1612 
1613 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1614 
1615 	cpu_install_idmap();
1616 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1617 	cpu_uninstall_idmap();
1618 
1619 	if (!cpu)
1620 		arm64_use_ng_mappings = true;
1621 }
1622 #else
1623 static void
1624 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1625 {
1626 }
1627 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1628 
1629 static int __init parse_kpti(char *str)
1630 {
1631 	bool enabled;
1632 	int ret = strtobool(str, &enabled);
1633 
1634 	if (ret)
1635 		return ret;
1636 
1637 	__kpti_forced = enabled ? 1 : -1;
1638 	return 0;
1639 }
1640 early_param("kpti", parse_kpti);
1641 
1642 #ifdef CONFIG_ARM64_HW_AFDBM
1643 static inline void __cpu_enable_hw_dbm(void)
1644 {
1645 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1646 
1647 	write_sysreg(tcr, tcr_el1);
1648 	isb();
1649 	local_flush_tlb_all();
1650 }
1651 
1652 static bool cpu_has_broken_dbm(void)
1653 {
1654 	/* List of CPUs which have broken DBM support. */
1655 	static const struct midr_range cpus[] = {
1656 #ifdef CONFIG_ARM64_ERRATUM_1024718
1657 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1658 		/* Kryo4xx Silver (rdpe => r1p0) */
1659 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1660 #endif
1661 #ifdef CONFIG_ARM64_ERRATUM_2051678
1662 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1663 #endif
1664 		{},
1665 	};
1666 
1667 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1668 }
1669 
1670 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1671 {
1672 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1673 	       !cpu_has_broken_dbm();
1674 }
1675 
1676 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1677 {
1678 	if (cpu_can_use_dbm(cap))
1679 		__cpu_enable_hw_dbm();
1680 }
1681 
1682 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1683 		       int __unused)
1684 {
1685 	static bool detected = false;
1686 	/*
1687 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1688 	 * run a mix of CPUs with and without the feature. So, we
1689 	 * unconditionally enable the capability to allow any late CPU
1690 	 * to use the feature. We only enable the control bits on the
1691 	 * CPU, if it actually supports.
1692 	 *
1693 	 * We have to make sure we print the "feature" detection only
1694 	 * when at least one CPU actually uses it. So check if this CPU
1695 	 * can actually use it and print the message exactly once.
1696 	 *
1697 	 * This is safe as all CPUs (including secondary CPUs - due to the
1698 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1699 	 * goes through the "matches" check exactly once. Also if a CPU
1700 	 * matches the criteria, it is guaranteed that the CPU will turn
1701 	 * the DBM on, as the capability is unconditionally enabled.
1702 	 */
1703 	if (!detected && cpu_can_use_dbm(cap)) {
1704 		detected = true;
1705 		pr_info("detected: Hardware dirty bit management\n");
1706 	}
1707 
1708 	return true;
1709 }
1710 
1711 #endif
1712 
1713 #ifdef CONFIG_ARM64_AMU_EXTN
1714 
1715 /*
1716  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1717  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1718  * information regarding all the events that it supports. When a CPU bit is
1719  * set in the cpumask, the user of this feature can only rely on the presence
1720  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1721  * counters are enabled or access to these counters is enabled by code
1722  * executed at higher exception levels (firmware).
1723  */
1724 static struct cpumask amu_cpus __read_mostly;
1725 
1726 bool cpu_has_amu_feat(int cpu)
1727 {
1728 	return cpumask_test_cpu(cpu, &amu_cpus);
1729 }
1730 
1731 int get_cpu_with_amu_feat(void)
1732 {
1733 	return cpumask_any(&amu_cpus);
1734 }
1735 
1736 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1737 {
1738 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1739 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1740 			smp_processor_id());
1741 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1742 		update_freq_counters_refs();
1743 	}
1744 }
1745 
1746 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1747 		    int __unused)
1748 {
1749 	/*
1750 	 * The AMU extension is a non-conflicting feature: the kernel can
1751 	 * safely run a mix of CPUs with and without support for the
1752 	 * activity monitors extension. Therefore, unconditionally enable
1753 	 * the capability to allow any late CPU to use the feature.
1754 	 *
1755 	 * With this feature unconditionally enabled, the cpu_enable
1756 	 * function will be called for all CPUs that match the criteria,
1757 	 * including secondary and hotplugged, marking this feature as
1758 	 * present on that respective CPU. The enable function will also
1759 	 * print a detection message.
1760 	 */
1761 
1762 	return true;
1763 }
1764 #else
1765 int get_cpu_with_amu_feat(void)
1766 {
1767 	return nr_cpu_ids;
1768 }
1769 #endif
1770 
1771 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1772 {
1773 	return is_kernel_in_hyp_mode();
1774 }
1775 
1776 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1777 {
1778 	/*
1779 	 * Copy register values that aren't redirected by hardware.
1780 	 *
1781 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1782 	 * this value to tpidr_el2 before we patch the code. Once we've done
1783 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1784 	 * do anything here.
1785 	 */
1786 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1787 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1788 }
1789 
1790 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1791 {
1792 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1793 
1794 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1795 	WARN_ON(CLIDR_LOUU(val) || CLIDR_LOUIS(val));
1796 }
1797 
1798 #ifdef CONFIG_ARM64_PAN
1799 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1800 {
1801 	/*
1802 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1803 	 * is discarded once we return from the exception.
1804 	 */
1805 	WARN_ON_ONCE(in_interrupt());
1806 
1807 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1808 	set_pstate_pan(1);
1809 }
1810 #endif /* CONFIG_ARM64_PAN */
1811 
1812 #ifdef CONFIG_ARM64_RAS_EXTN
1813 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1814 {
1815 	/* Firmware may have left a deferred SError in this register. */
1816 	write_sysreg_s(0, SYS_DISR_EL1);
1817 }
1818 #endif /* CONFIG_ARM64_RAS_EXTN */
1819 
1820 #ifdef CONFIG_ARM64_PTR_AUTH
1821 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1822 {
1823 	int boot_val, sec_val;
1824 
1825 	/* We don't expect to be called with SCOPE_SYSTEM */
1826 	WARN_ON(scope == SCOPE_SYSTEM);
1827 	/*
1828 	 * The ptr-auth feature levels are not intercompatible with lower
1829 	 * levels. Hence we must match ptr-auth feature level of the secondary
1830 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1831 	 * from the sanitised register whereas direct register read is done for
1832 	 * the secondary CPUs.
1833 	 * The sanitised feature state is guaranteed to match that of the
1834 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1835 	 * a chance to update the state, with the capability.
1836 	 */
1837 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1838 					       entry->field_pos, entry->sign);
1839 	if (scope & SCOPE_BOOT_CPU)
1840 		return boot_val >= entry->min_field_value;
1841 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1842 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1843 					      entry->field_pos, entry->sign);
1844 	return sec_val == boot_val;
1845 }
1846 
1847 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1848 				     int scope)
1849 {
1850 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1851 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1852 }
1853 
1854 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1855 			     int __unused)
1856 {
1857 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1858 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1859 }
1860 #endif /* CONFIG_ARM64_PTR_AUTH */
1861 
1862 #ifdef CONFIG_ARM64_E0PD
1863 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1864 {
1865 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1866 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1867 }
1868 #endif /* CONFIG_ARM64_E0PD */
1869 
1870 #ifdef CONFIG_ARM64_PSEUDO_NMI
1871 static bool enable_pseudo_nmi;
1872 
1873 static int __init early_enable_pseudo_nmi(char *p)
1874 {
1875 	return strtobool(p, &enable_pseudo_nmi);
1876 }
1877 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1878 
1879 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1880 				   int scope)
1881 {
1882 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1883 }
1884 #endif
1885 
1886 #ifdef CONFIG_ARM64_BTI
1887 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1888 {
1889 	/*
1890 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1891 	 * function entry points using BR is a requirement for
1892 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1893 	 * So, be strict and forbid other BRs using other registers to
1894 	 * jump onto a PACIxSP instruction:
1895 	 */
1896 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1897 	isb();
1898 }
1899 #endif /* CONFIG_ARM64_BTI */
1900 
1901 #ifdef CONFIG_ARM64_MTE
1902 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1903 {
1904 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
1905 	isb();
1906 
1907 	/*
1908 	 * Clear the tags in the zero page. This needs to be done via the
1909 	 * linear map which has the Tagged attribute.
1910 	 */
1911 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1912 		mte_clear_page_tags(lm_alias(empty_zero_page));
1913 
1914 	kasan_init_hw_tags_cpu();
1915 }
1916 #endif /* CONFIG_ARM64_MTE */
1917 
1918 #ifdef CONFIG_KVM
1919 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1920 {
1921 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1922 		return false;
1923 
1924 	if (is_kernel_in_hyp_mode()) {
1925 		pr_warn("Protected KVM not available with VHE\n");
1926 		return false;
1927 	}
1928 
1929 	return true;
1930 }
1931 #endif /* CONFIG_KVM */
1932 
1933 /* Internal helper functions to match cpu capability type */
1934 static bool
1935 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1936 {
1937 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1938 }
1939 
1940 static bool
1941 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1942 {
1943 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1944 }
1945 
1946 static bool
1947 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1948 {
1949 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1950 }
1951 
1952 static const struct arm64_cpu_capabilities arm64_features[] = {
1953 	{
1954 		.desc = "GIC system register CPU interface",
1955 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1956 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1957 		.matches = has_useable_gicv3_cpuif,
1958 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1959 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1960 		.sign = FTR_UNSIGNED,
1961 		.min_field_value = 1,
1962 	},
1963 	{
1964 		.desc = "Enhanced Counter Virtualization",
1965 		.capability = ARM64_HAS_ECV,
1966 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1967 		.matches = has_cpuid_feature,
1968 		.sys_reg = SYS_ID_AA64MMFR0_EL1,
1969 		.field_pos = ID_AA64MMFR0_ECV_SHIFT,
1970 		.sign = FTR_UNSIGNED,
1971 		.min_field_value = 1,
1972 	},
1973 #ifdef CONFIG_ARM64_PAN
1974 	{
1975 		.desc = "Privileged Access Never",
1976 		.capability = ARM64_HAS_PAN,
1977 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1978 		.matches = has_cpuid_feature,
1979 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1980 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1981 		.sign = FTR_UNSIGNED,
1982 		.min_field_value = 1,
1983 		.cpu_enable = cpu_enable_pan,
1984 	},
1985 #endif /* CONFIG_ARM64_PAN */
1986 #ifdef CONFIG_ARM64_EPAN
1987 	{
1988 		.desc = "Enhanced Privileged Access Never",
1989 		.capability = ARM64_HAS_EPAN,
1990 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1991 		.matches = has_cpuid_feature,
1992 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1993 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1994 		.sign = FTR_UNSIGNED,
1995 		.min_field_value = 3,
1996 	},
1997 #endif /* CONFIG_ARM64_EPAN */
1998 #ifdef CONFIG_ARM64_LSE_ATOMICS
1999 	{
2000 		.desc = "LSE atomic instructions",
2001 		.capability = ARM64_HAS_LSE_ATOMICS,
2002 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2003 		.matches = has_cpuid_feature,
2004 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2005 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
2006 		.sign = FTR_UNSIGNED,
2007 		.min_field_value = 2,
2008 	},
2009 #endif /* CONFIG_ARM64_LSE_ATOMICS */
2010 	{
2011 		.desc = "Software prefetching using PRFM",
2012 		.capability = ARM64_HAS_NO_HW_PREFETCH,
2013 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2014 		.matches = has_no_hw_prefetch,
2015 	},
2016 	{
2017 		.desc = "Virtualization Host Extensions",
2018 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
2019 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2020 		.matches = runs_at_el2,
2021 		.cpu_enable = cpu_copy_el2regs,
2022 	},
2023 	{
2024 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2025 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2026 		.matches = has_32bit_el0,
2027 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2028 		.sign = FTR_UNSIGNED,
2029 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
2030 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2031 	},
2032 #ifdef CONFIG_KVM
2033 	{
2034 		.desc = "32-bit EL1 Support",
2035 		.capability = ARM64_HAS_32BIT_EL1,
2036 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2037 		.matches = has_cpuid_feature,
2038 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2039 		.sign = FTR_UNSIGNED,
2040 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
2041 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2042 	},
2043 	{
2044 		.desc = "Protected KVM",
2045 		.capability = ARM64_KVM_PROTECTED_MODE,
2046 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2047 		.matches = is_kvm_protected_mode,
2048 	},
2049 #endif
2050 	{
2051 		.desc = "Kernel page table isolation (KPTI)",
2052 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2053 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2054 		/*
2055 		 * The ID feature fields below are used to indicate that
2056 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2057 		 * more details.
2058 		 */
2059 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2060 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
2061 		.min_field_value = 1,
2062 		.matches = unmap_kernel_at_el0,
2063 		.cpu_enable = kpti_install_ng_mappings,
2064 	},
2065 	{
2066 		/* FP/SIMD is not implemented */
2067 		.capability = ARM64_HAS_NO_FPSIMD,
2068 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2069 		.min_field_value = 0,
2070 		.matches = has_no_fpsimd,
2071 	},
2072 #ifdef CONFIG_ARM64_PMEM
2073 	{
2074 		.desc = "Data cache clean to Point of Persistence",
2075 		.capability = ARM64_HAS_DCPOP,
2076 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2077 		.matches = has_cpuid_feature,
2078 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2079 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2080 		.min_field_value = 1,
2081 	},
2082 	{
2083 		.desc = "Data cache clean to Point of Deep Persistence",
2084 		.capability = ARM64_HAS_DCPODP,
2085 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2086 		.matches = has_cpuid_feature,
2087 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2088 		.sign = FTR_UNSIGNED,
2089 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2090 		.min_field_value = 2,
2091 	},
2092 #endif
2093 #ifdef CONFIG_ARM64_SVE
2094 	{
2095 		.desc = "Scalable Vector Extension",
2096 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2097 		.capability = ARM64_SVE,
2098 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2099 		.sign = FTR_UNSIGNED,
2100 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2101 		.min_field_value = ID_AA64PFR0_SVE,
2102 		.matches = has_cpuid_feature,
2103 		.cpu_enable = sve_kernel_enable,
2104 	},
2105 #endif /* CONFIG_ARM64_SVE */
2106 #ifdef CONFIG_ARM64_RAS_EXTN
2107 	{
2108 		.desc = "RAS Extension Support",
2109 		.capability = ARM64_HAS_RAS_EXTN,
2110 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2111 		.matches = has_cpuid_feature,
2112 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2113 		.sign = FTR_UNSIGNED,
2114 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2115 		.min_field_value = ID_AA64PFR0_RAS_V1,
2116 		.cpu_enable = cpu_clear_disr,
2117 	},
2118 #endif /* CONFIG_ARM64_RAS_EXTN */
2119 #ifdef CONFIG_ARM64_AMU_EXTN
2120 	{
2121 		/*
2122 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2123 		 * Therefore, don't provide .desc as we don't want the detection
2124 		 * message to be shown until at least one CPU is detected to
2125 		 * support the feature.
2126 		 */
2127 		.capability = ARM64_HAS_AMU_EXTN,
2128 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2129 		.matches = has_amu,
2130 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2131 		.sign = FTR_UNSIGNED,
2132 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2133 		.min_field_value = ID_AA64PFR0_AMU,
2134 		.cpu_enable = cpu_amu_enable,
2135 	},
2136 #endif /* CONFIG_ARM64_AMU_EXTN */
2137 	{
2138 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2139 		.capability = ARM64_HAS_CACHE_IDC,
2140 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2141 		.matches = has_cache_idc,
2142 		.cpu_enable = cpu_emulate_effective_ctr,
2143 	},
2144 	{
2145 		.desc = "Instruction cache invalidation not required for I/D coherence",
2146 		.capability = ARM64_HAS_CACHE_DIC,
2147 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2148 		.matches = has_cache_dic,
2149 	},
2150 	{
2151 		.desc = "Stage-2 Force Write-Back",
2152 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2153 		.capability = ARM64_HAS_STAGE2_FWB,
2154 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2155 		.sign = FTR_UNSIGNED,
2156 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2157 		.min_field_value = 1,
2158 		.matches = has_cpuid_feature,
2159 		.cpu_enable = cpu_has_fwb,
2160 	},
2161 	{
2162 		.desc = "ARMv8.4 Translation Table Level",
2163 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2164 		.capability = ARM64_HAS_ARMv8_4_TTL,
2165 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2166 		.sign = FTR_UNSIGNED,
2167 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2168 		.min_field_value = 1,
2169 		.matches = has_cpuid_feature,
2170 	},
2171 	{
2172 		.desc = "TLB range maintenance instructions",
2173 		.capability = ARM64_HAS_TLB_RANGE,
2174 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2175 		.matches = has_cpuid_feature,
2176 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2177 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
2178 		.sign = FTR_UNSIGNED,
2179 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
2180 	},
2181 #ifdef CONFIG_ARM64_HW_AFDBM
2182 	{
2183 		/*
2184 		 * Since we turn this on always, we don't want the user to
2185 		 * think that the feature is available when it may not be.
2186 		 * So hide the description.
2187 		 *
2188 		 * .desc = "Hardware pagetable Dirty Bit Management",
2189 		 *
2190 		 */
2191 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2192 		.capability = ARM64_HW_DBM,
2193 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2194 		.sign = FTR_UNSIGNED,
2195 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2196 		.min_field_value = 2,
2197 		.matches = has_hw_dbm,
2198 		.cpu_enable = cpu_enable_hw_dbm,
2199 	},
2200 #endif
2201 	{
2202 		.desc = "CRC32 instructions",
2203 		.capability = ARM64_HAS_CRC32,
2204 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2205 		.matches = has_cpuid_feature,
2206 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2207 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2208 		.min_field_value = 1,
2209 	},
2210 	{
2211 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2212 		.capability = ARM64_SSBS,
2213 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2214 		.matches = has_cpuid_feature,
2215 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2216 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2217 		.sign = FTR_UNSIGNED,
2218 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2219 	},
2220 #ifdef CONFIG_ARM64_CNP
2221 	{
2222 		.desc = "Common not Private translations",
2223 		.capability = ARM64_HAS_CNP,
2224 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2225 		.matches = has_useable_cnp,
2226 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2227 		.sign = FTR_UNSIGNED,
2228 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2229 		.min_field_value = 1,
2230 		.cpu_enable = cpu_enable_cnp,
2231 	},
2232 #endif
2233 	{
2234 		.desc = "Speculation barrier (SB)",
2235 		.capability = ARM64_HAS_SB,
2236 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2237 		.matches = has_cpuid_feature,
2238 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2239 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2240 		.sign = FTR_UNSIGNED,
2241 		.min_field_value = 1,
2242 	},
2243 #ifdef CONFIG_ARM64_PTR_AUTH
2244 	{
2245 		.desc = "Address authentication (architected algorithm)",
2246 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2247 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2248 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2249 		.sign = FTR_UNSIGNED,
2250 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2251 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2252 		.matches = has_address_auth_cpucap,
2253 	},
2254 	{
2255 		.desc = "Address authentication (IMP DEF algorithm)",
2256 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2257 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2258 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2259 		.sign = FTR_UNSIGNED,
2260 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2261 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2262 		.matches = has_address_auth_cpucap,
2263 	},
2264 	{
2265 		.capability = ARM64_HAS_ADDRESS_AUTH,
2266 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2267 		.matches = has_address_auth_metacap,
2268 	},
2269 	{
2270 		.desc = "Generic authentication (architected algorithm)",
2271 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2272 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2273 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2274 		.sign = FTR_UNSIGNED,
2275 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2276 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2277 		.matches = has_cpuid_feature,
2278 	},
2279 	{
2280 		.desc = "Generic authentication (IMP DEF algorithm)",
2281 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2282 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2283 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2284 		.sign = FTR_UNSIGNED,
2285 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2286 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2287 		.matches = has_cpuid_feature,
2288 	},
2289 	{
2290 		.capability = ARM64_HAS_GENERIC_AUTH,
2291 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2292 		.matches = has_generic_auth,
2293 	},
2294 #endif /* CONFIG_ARM64_PTR_AUTH */
2295 #ifdef CONFIG_ARM64_PSEUDO_NMI
2296 	{
2297 		/*
2298 		 * Depends on having GICv3
2299 		 */
2300 		.desc = "IRQ priority masking",
2301 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2302 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2303 		.matches = can_use_gic_priorities,
2304 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2305 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2306 		.sign = FTR_UNSIGNED,
2307 		.min_field_value = 1,
2308 	},
2309 #endif
2310 #ifdef CONFIG_ARM64_E0PD
2311 	{
2312 		.desc = "E0PD",
2313 		.capability = ARM64_HAS_E0PD,
2314 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2315 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2316 		.sign = FTR_UNSIGNED,
2317 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2318 		.matches = has_cpuid_feature,
2319 		.min_field_value = 1,
2320 		.cpu_enable = cpu_enable_e0pd,
2321 	},
2322 #endif
2323 #ifdef CONFIG_ARCH_RANDOM
2324 	{
2325 		.desc = "Random Number Generator",
2326 		.capability = ARM64_HAS_RNG,
2327 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2328 		.matches = has_cpuid_feature,
2329 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2330 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2331 		.sign = FTR_UNSIGNED,
2332 		.min_field_value = 1,
2333 	},
2334 #endif
2335 #ifdef CONFIG_ARM64_BTI
2336 	{
2337 		.desc = "Branch Target Identification",
2338 		.capability = ARM64_BTI,
2339 #ifdef CONFIG_ARM64_BTI_KERNEL
2340 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2341 #else
2342 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2343 #endif
2344 		.matches = has_cpuid_feature,
2345 		.cpu_enable = bti_enable,
2346 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2347 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2348 		.min_field_value = ID_AA64PFR1_BT_BTI,
2349 		.sign = FTR_UNSIGNED,
2350 	},
2351 #endif
2352 #ifdef CONFIG_ARM64_MTE
2353 	{
2354 		.desc = "Memory Tagging Extension",
2355 		.capability = ARM64_MTE,
2356 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2357 		.matches = has_cpuid_feature,
2358 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2359 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2360 		.min_field_value = ID_AA64PFR1_MTE,
2361 		.sign = FTR_UNSIGNED,
2362 		.cpu_enable = cpu_enable_mte,
2363 	},
2364 	{
2365 		.desc = "Asymmetric MTE Tag Check Fault",
2366 		.capability = ARM64_MTE_ASYMM,
2367 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2368 		.matches = has_cpuid_feature,
2369 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2370 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2371 		.min_field_value = ID_AA64PFR1_MTE_ASYMM,
2372 		.sign = FTR_UNSIGNED,
2373 	},
2374 #endif /* CONFIG_ARM64_MTE */
2375 	{
2376 		.desc = "RCpc load-acquire (LDAPR)",
2377 		.capability = ARM64_HAS_LDAPR,
2378 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2379 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2380 		.sign = FTR_UNSIGNED,
2381 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2382 		.matches = has_cpuid_feature,
2383 		.min_field_value = 1,
2384 	},
2385 	{},
2386 };
2387 
2388 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2389 		.matches = has_cpuid_feature,					\
2390 		.sys_reg = reg,							\
2391 		.field_pos = field,						\
2392 		.sign = s,							\
2393 		.min_field_value = min_value,
2394 
2395 #define __HWCAP_CAP(name, cap_type, cap)					\
2396 		.desc = name,							\
2397 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2398 		.hwcap_type = cap_type,						\
2399 		.hwcap = cap,							\
2400 
2401 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2402 	{									\
2403 		__HWCAP_CAP(#cap, cap_type, cap)				\
2404 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2405 	}
2406 
2407 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2408 	{									\
2409 		__HWCAP_CAP(#cap, cap_type, cap)				\
2410 		.matches = cpucap_multi_entry_cap_matches,			\
2411 		.match_list = list,						\
2412 	}
2413 
2414 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2415 	{									\
2416 		__HWCAP_CAP(#cap, cap_type, cap)				\
2417 		.matches = match,						\
2418 	}
2419 
2420 #ifdef CONFIG_ARM64_PTR_AUTH
2421 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2422 	{
2423 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2424 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2425 	},
2426 	{
2427 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2428 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2429 	},
2430 	{},
2431 };
2432 
2433 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2434 	{
2435 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2436 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2437 	},
2438 	{
2439 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2440 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2441 	},
2442 	{},
2443 };
2444 #endif
2445 
2446 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2447 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2448 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2449 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2450 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2451 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2452 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2453 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2454 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2455 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2456 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2457 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2458 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2459 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2460 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2461 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2462 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2463 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2464 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2465 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2466 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2467 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2468 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2469 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2470 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2471 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2472 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2473 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2474 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2475 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2476 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2477 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2478 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2479 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2480 #ifdef CONFIG_ARM64_SVE
2481 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2482 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2483 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2484 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2485 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2486 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2487 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2488 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2489 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2490 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2491 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2492 #endif
2493 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2494 #ifdef CONFIG_ARM64_BTI
2495 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2496 #endif
2497 #ifdef CONFIG_ARM64_PTR_AUTH
2498 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2499 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2500 #endif
2501 #ifdef CONFIG_ARM64_MTE
2502 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2503 #endif /* CONFIG_ARM64_MTE */
2504 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2505 	HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
2506 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2507 	{},
2508 };
2509 
2510 #ifdef CONFIG_COMPAT
2511 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2512 {
2513 	/*
2514 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2515 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2516 	 * check is future proof, by making sure value is non-zero.
2517 	 */
2518 	u32 mvfr1;
2519 
2520 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2521 	if (scope == SCOPE_SYSTEM)
2522 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2523 	else
2524 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2525 
2526 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2527 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2528 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2529 }
2530 #endif
2531 
2532 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2533 #ifdef CONFIG_COMPAT
2534 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2535 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2536 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2537 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2538 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2539 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2540 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2541 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2542 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2543 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2544 #endif
2545 	{},
2546 };
2547 
2548 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2549 {
2550 	switch (cap->hwcap_type) {
2551 	case CAP_HWCAP:
2552 		cpu_set_feature(cap->hwcap);
2553 		break;
2554 #ifdef CONFIG_COMPAT
2555 	case CAP_COMPAT_HWCAP:
2556 		compat_elf_hwcap |= (u32)cap->hwcap;
2557 		break;
2558 	case CAP_COMPAT_HWCAP2:
2559 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2560 		break;
2561 #endif
2562 	default:
2563 		WARN_ON(1);
2564 		break;
2565 	}
2566 }
2567 
2568 /* Check if we have a particular HWCAP enabled */
2569 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2570 {
2571 	bool rc;
2572 
2573 	switch (cap->hwcap_type) {
2574 	case CAP_HWCAP:
2575 		rc = cpu_have_feature(cap->hwcap);
2576 		break;
2577 #ifdef CONFIG_COMPAT
2578 	case CAP_COMPAT_HWCAP:
2579 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2580 		break;
2581 	case CAP_COMPAT_HWCAP2:
2582 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2583 		break;
2584 #endif
2585 	default:
2586 		WARN_ON(1);
2587 		rc = false;
2588 	}
2589 
2590 	return rc;
2591 }
2592 
2593 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2594 {
2595 	/* We support emulation of accesses to CPU ID feature registers */
2596 	cpu_set_named_feature(CPUID);
2597 	for (; hwcaps->matches; hwcaps++)
2598 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2599 			cap_set_elf_hwcap(hwcaps);
2600 }
2601 
2602 static void update_cpu_capabilities(u16 scope_mask)
2603 {
2604 	int i;
2605 	const struct arm64_cpu_capabilities *caps;
2606 
2607 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2608 	for (i = 0; i < ARM64_NCAPS; i++) {
2609 		caps = cpu_hwcaps_ptrs[i];
2610 		if (!caps || !(caps->type & scope_mask) ||
2611 		    cpus_have_cap(caps->capability) ||
2612 		    !caps->matches(caps, cpucap_default_scope(caps)))
2613 			continue;
2614 
2615 		if (caps->desc)
2616 			pr_info("detected: %s\n", caps->desc);
2617 		cpus_set_cap(caps->capability);
2618 
2619 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2620 			set_bit(caps->capability, boot_capabilities);
2621 	}
2622 }
2623 
2624 /*
2625  * Enable all the available capabilities on this CPU. The capabilities
2626  * with BOOT_CPU scope are handled separately and hence skipped here.
2627  */
2628 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2629 {
2630 	int i;
2631 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2632 
2633 	for_each_available_cap(i) {
2634 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2635 
2636 		if (WARN_ON(!cap))
2637 			continue;
2638 
2639 		if (!(cap->type & non_boot_scope))
2640 			continue;
2641 
2642 		if (cap->cpu_enable)
2643 			cap->cpu_enable(cap);
2644 	}
2645 	return 0;
2646 }
2647 
2648 /*
2649  * Run through the enabled capabilities and enable() it on all active
2650  * CPUs
2651  */
2652 static void __init enable_cpu_capabilities(u16 scope_mask)
2653 {
2654 	int i;
2655 	const struct arm64_cpu_capabilities *caps;
2656 	bool boot_scope;
2657 
2658 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2659 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2660 
2661 	for (i = 0; i < ARM64_NCAPS; i++) {
2662 		unsigned int num;
2663 
2664 		caps = cpu_hwcaps_ptrs[i];
2665 		if (!caps || !(caps->type & scope_mask))
2666 			continue;
2667 		num = caps->capability;
2668 		if (!cpus_have_cap(num))
2669 			continue;
2670 
2671 		/* Ensure cpus_have_const_cap(num) works */
2672 		static_branch_enable(&cpu_hwcap_keys[num]);
2673 
2674 		if (boot_scope && caps->cpu_enable)
2675 			/*
2676 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2677 			 * before any secondary CPU boots. Thus, each secondary
2678 			 * will enable the capability as appropriate via
2679 			 * check_local_cpu_capabilities(). The only exception is
2680 			 * the boot CPU, for which the capability must be
2681 			 * enabled here. This approach avoids costly
2682 			 * stop_machine() calls for this case.
2683 			 */
2684 			caps->cpu_enable(caps);
2685 	}
2686 
2687 	/*
2688 	 * For all non-boot scope capabilities, use stop_machine()
2689 	 * as it schedules the work allowing us to modify PSTATE,
2690 	 * instead of on_each_cpu() which uses an IPI, giving us a
2691 	 * PSTATE that disappears when we return.
2692 	 */
2693 	if (!boot_scope)
2694 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2695 			     NULL, cpu_online_mask);
2696 }
2697 
2698 /*
2699  * Run through the list of capabilities to check for conflicts.
2700  * If the system has already detected a capability, take necessary
2701  * action on this CPU.
2702  */
2703 static void verify_local_cpu_caps(u16 scope_mask)
2704 {
2705 	int i;
2706 	bool cpu_has_cap, system_has_cap;
2707 	const struct arm64_cpu_capabilities *caps;
2708 
2709 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2710 
2711 	for (i = 0; i < ARM64_NCAPS; i++) {
2712 		caps = cpu_hwcaps_ptrs[i];
2713 		if (!caps || !(caps->type & scope_mask))
2714 			continue;
2715 
2716 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2717 		system_has_cap = cpus_have_cap(caps->capability);
2718 
2719 		if (system_has_cap) {
2720 			/*
2721 			 * Check if the new CPU misses an advertised feature,
2722 			 * which is not safe to miss.
2723 			 */
2724 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2725 				break;
2726 			/*
2727 			 * We have to issue cpu_enable() irrespective of
2728 			 * whether the CPU has it or not, as it is enabeld
2729 			 * system wide. It is upto the call back to take
2730 			 * appropriate action on this CPU.
2731 			 */
2732 			if (caps->cpu_enable)
2733 				caps->cpu_enable(caps);
2734 		} else {
2735 			/*
2736 			 * Check if the CPU has this capability if it isn't
2737 			 * safe to have when the system doesn't.
2738 			 */
2739 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2740 				break;
2741 		}
2742 	}
2743 
2744 	if (i < ARM64_NCAPS) {
2745 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2746 			smp_processor_id(), caps->capability,
2747 			caps->desc, system_has_cap, cpu_has_cap);
2748 
2749 		if (cpucap_panic_on_conflict(caps))
2750 			cpu_panic_kernel();
2751 		else
2752 			cpu_die_early();
2753 	}
2754 }
2755 
2756 /*
2757  * Check for CPU features that are used in early boot
2758  * based on the Boot CPU value.
2759  */
2760 static void check_early_cpu_features(void)
2761 {
2762 	verify_cpu_asid_bits();
2763 
2764 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2765 }
2766 
2767 static void
2768 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2769 {
2770 
2771 	for (; caps->matches; caps++)
2772 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2773 			pr_crit("CPU%d: missing HWCAP: %s\n",
2774 					smp_processor_id(), caps->desc);
2775 			cpu_die_early();
2776 		}
2777 }
2778 
2779 static void verify_local_elf_hwcaps(void)
2780 {
2781 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2782 
2783 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2784 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2785 }
2786 
2787 static void verify_sve_features(void)
2788 {
2789 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2790 	u64 zcr = read_zcr_features();
2791 
2792 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2793 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2794 
2795 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SVE)) {
2796 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2797 			smp_processor_id());
2798 		cpu_die_early();
2799 	}
2800 
2801 	/* Add checks on other ZCR bits here if necessary */
2802 }
2803 
2804 static void verify_hyp_capabilities(void)
2805 {
2806 	u64 safe_mmfr1, mmfr0, mmfr1;
2807 	int parange, ipa_max;
2808 	unsigned int safe_vmid_bits, vmid_bits;
2809 
2810 	if (!IS_ENABLED(CONFIG_KVM))
2811 		return;
2812 
2813 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2814 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2815 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2816 
2817 	/* Verify VMID bits */
2818 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2819 	vmid_bits = get_vmid_bits(mmfr1);
2820 	if (vmid_bits < safe_vmid_bits) {
2821 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2822 		cpu_die_early();
2823 	}
2824 
2825 	/* Verify IPA range */
2826 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2827 				ID_AA64MMFR0_PARANGE_SHIFT);
2828 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2829 	if (ipa_max < get_kvm_ipa_limit()) {
2830 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2831 		cpu_die_early();
2832 	}
2833 }
2834 
2835 /*
2836  * Run through the enabled system capabilities and enable() it on this CPU.
2837  * The capabilities were decided based on the available CPUs at the boot time.
2838  * Any new CPU should match the system wide status of the capability. If the
2839  * new CPU doesn't have a capability which the system now has enabled, we
2840  * cannot do anything to fix it up and could cause unexpected failures. So
2841  * we park the CPU.
2842  */
2843 static void verify_local_cpu_capabilities(void)
2844 {
2845 	/*
2846 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2847 	 * check_early_cpu_features(), as they need to be verified
2848 	 * on all secondary CPUs.
2849 	 */
2850 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2851 	verify_local_elf_hwcaps();
2852 
2853 	if (system_supports_sve())
2854 		verify_sve_features();
2855 
2856 	if (is_hyp_mode_available())
2857 		verify_hyp_capabilities();
2858 }
2859 
2860 void check_local_cpu_capabilities(void)
2861 {
2862 	/*
2863 	 * All secondary CPUs should conform to the early CPU features
2864 	 * in use by the kernel based on boot CPU.
2865 	 */
2866 	check_early_cpu_features();
2867 
2868 	/*
2869 	 * If we haven't finalised the system capabilities, this CPU gets
2870 	 * a chance to update the errata work arounds and local features.
2871 	 * Otherwise, this CPU should verify that it has all the system
2872 	 * advertised capabilities.
2873 	 */
2874 	if (!system_capabilities_finalized())
2875 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2876 	else
2877 		verify_local_cpu_capabilities();
2878 }
2879 
2880 static void __init setup_boot_cpu_capabilities(void)
2881 {
2882 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2883 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2884 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2885 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2886 }
2887 
2888 bool this_cpu_has_cap(unsigned int n)
2889 {
2890 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2891 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2892 
2893 		if (cap)
2894 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2895 	}
2896 
2897 	return false;
2898 }
2899 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
2900 
2901 /*
2902  * This helper function is used in a narrow window when,
2903  * - The system wide safe registers are set with all the SMP CPUs and,
2904  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2905  * In all other cases cpus_have_{const_}cap() should be used.
2906  */
2907 static bool __maybe_unused __system_matches_cap(unsigned int n)
2908 {
2909 	if (n < ARM64_NCAPS) {
2910 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2911 
2912 		if (cap)
2913 			return cap->matches(cap, SCOPE_SYSTEM);
2914 	}
2915 	return false;
2916 }
2917 
2918 void cpu_set_feature(unsigned int num)
2919 {
2920 	WARN_ON(num >= MAX_CPU_FEATURES);
2921 	elf_hwcap |= BIT(num);
2922 }
2923 EXPORT_SYMBOL_GPL(cpu_set_feature);
2924 
2925 bool cpu_have_feature(unsigned int num)
2926 {
2927 	WARN_ON(num >= MAX_CPU_FEATURES);
2928 	return elf_hwcap & BIT(num);
2929 }
2930 EXPORT_SYMBOL_GPL(cpu_have_feature);
2931 
2932 unsigned long cpu_get_elf_hwcap(void)
2933 {
2934 	/*
2935 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2936 	 * note that for userspace compatibility we guarantee that bits 62
2937 	 * and 63 will always be returned as 0.
2938 	 */
2939 	return lower_32_bits(elf_hwcap);
2940 }
2941 
2942 unsigned long cpu_get_elf_hwcap2(void)
2943 {
2944 	return upper_32_bits(elf_hwcap);
2945 }
2946 
2947 static void __init setup_system_capabilities(void)
2948 {
2949 	/*
2950 	 * We have finalised the system-wide safe feature
2951 	 * registers, finalise the capabilities that depend
2952 	 * on it. Also enable all the available capabilities,
2953 	 * that are not enabled already.
2954 	 */
2955 	update_cpu_capabilities(SCOPE_SYSTEM);
2956 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2957 }
2958 
2959 void __init setup_cpu_features(void)
2960 {
2961 	u32 cwg;
2962 
2963 	setup_system_capabilities();
2964 	setup_elf_hwcaps(arm64_elf_hwcaps);
2965 
2966 	if (system_supports_32bit_el0())
2967 		setup_elf_hwcaps(compat_elf_hwcaps);
2968 
2969 	if (system_uses_ttbr0_pan())
2970 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2971 
2972 	sve_setup();
2973 	minsigstksz_setup();
2974 
2975 	/* Advertise that we have computed the system capabilities */
2976 	finalize_system_capabilities();
2977 
2978 	/*
2979 	 * Check for sane CTR_EL0.CWG value.
2980 	 */
2981 	cwg = cache_type_cwg();
2982 	if (!cwg)
2983 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2984 			ARCH_DMA_MINALIGN);
2985 }
2986 
2987 static int enable_mismatched_32bit_el0(unsigned int cpu)
2988 {
2989 	/*
2990 	 * The first 32-bit-capable CPU we detected and so can no longer
2991 	 * be offlined by userspace. -1 indicates we haven't yet onlined
2992 	 * a 32-bit-capable CPU.
2993 	 */
2994 	static int lucky_winner = -1;
2995 
2996 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
2997 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
2998 
2999 	if (cpu_32bit) {
3000 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
3001 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
3002 	}
3003 
3004 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
3005 		return 0;
3006 
3007 	if (lucky_winner >= 0)
3008 		return 0;
3009 
3010 	/*
3011 	 * We've detected a mismatch. We need to keep one of our CPUs with
3012 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
3013 	 * every CPU in the system for a 32-bit task.
3014 	 */
3015 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
3016 							 cpu_active_mask);
3017 	get_cpu_device(lucky_winner)->offline_disabled = true;
3018 	setup_elf_hwcaps(compat_elf_hwcaps);
3019 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
3020 		cpu, lucky_winner);
3021 	return 0;
3022 }
3023 
3024 static int __init init_32bit_el0_mask(void)
3025 {
3026 	if (!allow_mismatched_32bit_el0)
3027 		return 0;
3028 
3029 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3030 		return -ENOMEM;
3031 
3032 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3033 				 "arm64/mismatched_32bit_el0:online",
3034 				 enable_mismatched_32bit_el0, NULL);
3035 }
3036 subsys_initcall_sync(init_32bit_el0_mask);
3037 
3038 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3039 {
3040 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
3041 }
3042 
3043 /*
3044  * We emulate only the following system register space.
3045  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
3046  * See Table C5-6 System instruction encodings for System register accesses,
3047  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3048  */
3049 static inline bool __attribute_const__ is_emulated(u32 id)
3050 {
3051 	return (sys_reg_Op0(id) == 0x3 &&
3052 		sys_reg_CRn(id) == 0x0 &&
3053 		sys_reg_Op1(id) == 0x0 &&
3054 		(sys_reg_CRm(id) == 0 ||
3055 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
3056 }
3057 
3058 /*
3059  * With CRm == 0, reg should be one of :
3060  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3061  */
3062 static inline int emulate_id_reg(u32 id, u64 *valp)
3063 {
3064 	switch (id) {
3065 	case SYS_MIDR_EL1:
3066 		*valp = read_cpuid_id();
3067 		break;
3068 	case SYS_MPIDR_EL1:
3069 		*valp = SYS_MPIDR_SAFE_VAL;
3070 		break;
3071 	case SYS_REVIDR_EL1:
3072 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3073 		*valp = 0;
3074 		break;
3075 	default:
3076 		return -EINVAL;
3077 	}
3078 
3079 	return 0;
3080 }
3081 
3082 static int emulate_sys_reg(u32 id, u64 *valp)
3083 {
3084 	struct arm64_ftr_reg *regp;
3085 
3086 	if (!is_emulated(id))
3087 		return -EINVAL;
3088 
3089 	if (sys_reg_CRm(id) == 0)
3090 		return emulate_id_reg(id, valp);
3091 
3092 	regp = get_arm64_ftr_reg_nowarn(id);
3093 	if (regp)
3094 		*valp = arm64_ftr_reg_user_value(regp);
3095 	else
3096 		/*
3097 		 * The untracked registers are either IMPLEMENTATION DEFINED
3098 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3099 		 */
3100 		*valp = 0;
3101 	return 0;
3102 }
3103 
3104 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3105 {
3106 	int rc;
3107 	u64 val;
3108 
3109 	rc = emulate_sys_reg(sys_reg, &val);
3110 	if (!rc) {
3111 		pt_regs_write_reg(regs, rt, val);
3112 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3113 	}
3114 	return rc;
3115 }
3116 
3117 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3118 {
3119 	u32 sys_reg, rt;
3120 
3121 	/*
3122 	 * sys_reg values are defined as used in mrs/msr instruction.
3123 	 * shift the imm value to get the encoding.
3124 	 */
3125 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3126 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3127 	return do_emulate_mrs(regs, sys_reg, rt);
3128 }
3129 
3130 static struct undef_hook mrs_hook = {
3131 	.instr_mask = 0xffff0000,
3132 	.instr_val  = 0xd5380000,
3133 	.pstate_mask = PSR_AA32_MODE_MASK,
3134 	.pstate_val = PSR_MODE_EL0t,
3135 	.fn = emulate_mrs,
3136 };
3137 
3138 static int __init enable_mrs_emulation(void)
3139 {
3140 	register_undef_hook(&mrs_hook);
3141 	return 0;
3142 }
3143 
3144 core_initcall(enable_mrs_emulation);
3145 
3146 enum mitigation_state arm64_get_meltdown_state(void)
3147 {
3148 	if (__meltdown_safe)
3149 		return SPECTRE_UNAFFECTED;
3150 
3151 	if (arm64_kernel_unmapped_at_el0())
3152 		return SPECTRE_MITIGATED;
3153 
3154 	return SPECTRE_VULNERABLE;
3155 }
3156 
3157 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3158 			  char *buf)
3159 {
3160 	switch (arm64_get_meltdown_state()) {
3161 	case SPECTRE_UNAFFECTED:
3162 		return sprintf(buf, "Not affected\n");
3163 
3164 	case SPECTRE_MITIGATED:
3165 		return sprintf(buf, "Mitigation: PTI\n");
3166 
3167 	default:
3168 		return sprintf(buf, "Vulnerable\n");
3169 	}
3170 }
3171