xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision 69868c3b)
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/types.h>
71 #include <linux/minmax.h>
72 #include <linux/mm.h>
73 #include <linux/cpu.h>
74 #include <linux/kasan.h>
75 #include <asm/cpu.h>
76 #include <asm/cpufeature.h>
77 #include <asm/cpu_ops.h>
78 #include <asm/fpsimd.h>
79 #include <asm/insn.h>
80 #include <asm/kvm_host.h>
81 #include <asm/mmu_context.h>
82 #include <asm/mte.h>
83 #include <asm/processor.h>
84 #include <asm/smp.h>
85 #include <asm/sysreg.h>
86 #include <asm/traps.h>
87 #include <asm/virt.h>
88 
89 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
90 static unsigned long elf_hwcap __read_mostly;
91 
92 #ifdef CONFIG_COMPAT
93 #define COMPAT_ELF_HWCAP_DEFAULT	\
94 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
95 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
96 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
97 				 COMPAT_HWCAP_LPAE)
98 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
99 unsigned int compat_elf_hwcap2 __read_mostly;
100 #endif
101 
102 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
103 EXPORT_SYMBOL(cpu_hwcaps);
104 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
105 
106 /* Need also bit for ARM64_CB_PATCH */
107 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
108 
109 bool arm64_use_ng_mappings = false;
110 EXPORT_SYMBOL(arm64_use_ng_mappings);
111 
112 /*
113  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
114  * support it?
115  */
116 static bool __read_mostly allow_mismatched_32bit_el0;
117 
118 /*
119  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
120  * seen at least one CPU capable of 32-bit EL0.
121  */
122 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
123 
124 /*
125  * Mask of CPUs supporting 32-bit EL0.
126  * Only valid if arm64_mismatched_32bit_el0 is enabled.
127  */
128 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
129 
130 /*
131  * Flag to indicate if we have computed the system wide
132  * capabilities based on the boot time active CPUs. This
133  * will be used to determine if a new booting CPU should
134  * go through the verification process to make sure that it
135  * supports the system capabilities, without using a hotplug
136  * notifier. This is also used to decide if we could use
137  * the fast path for checking constant CPU caps.
138  */
139 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
140 EXPORT_SYMBOL(arm64_const_caps_ready);
141 static inline void finalize_system_capabilities(void)
142 {
143 	static_branch_enable(&arm64_const_caps_ready);
144 }
145 
146 void dump_cpu_features(void)
147 {
148 	/* file-wide pr_fmt adds "CPU features: " prefix */
149 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
150 }
151 
152 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
153 EXPORT_SYMBOL(cpu_hwcap_keys);
154 
155 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
156 	{						\
157 		.sign = SIGNED,				\
158 		.visible = VISIBLE,			\
159 		.strict = STRICT,			\
160 		.type = TYPE,				\
161 		.shift = SHIFT,				\
162 		.width = WIDTH,				\
163 		.safe_val = SAFE_VAL,			\
164 	}
165 
166 /* Define a feature with unsigned values */
167 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
168 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
169 
170 /* Define a feature with a signed value */
171 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
172 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
173 
174 #define ARM64_FTR_END					\
175 	{						\
176 		.width = 0,				\
177 	}
178 
179 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
180 
181 static bool __system_matches_cap(unsigned int n);
182 
183 /*
184  * NOTE: Any changes to the visibility of features should be kept in
185  * sync with the documentation of the CPU feature register ABI.
186  */
187 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
188 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
189 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
190 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
192 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
202 	ARM64_FTR_END,
203 };
204 
205 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
206 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
213 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
215 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
220 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
221 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
222 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
223 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
224 	ARM64_FTR_END,
225 };
226 
227 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
228 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
229 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
231 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
232 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
233 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
234 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
235 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
236 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
238 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
239 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
240 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
244 	ARM64_FTR_END,
245 };
246 
247 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
248 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
251 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
252 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
253 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
254 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
255 	ARM64_FTR_END,
256 };
257 
258 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
259 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
260 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
261 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
262 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
263 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
264 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
265 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
266 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
267 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
268 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
269 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
270 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
271 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
272 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
277 	ARM64_FTR_END,
278 };
279 
280 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
281 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
282 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
284 	/*
285 	 * Page size not being supported at Stage-2 is not fatal. You
286 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
287 	 * your favourite nesting hypervisor.
288 	 *
289 	 * There is a small corner case where the hypervisor explicitly
290 	 * advertises a given granule size at Stage-2 (value 2) on some
291 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
292 	 * vCPUs. Although this is not forbidden by the architecture, it
293 	 * indicates that the hypervisor is being silly (or buggy).
294 	 *
295 	 * We make no effort to cope with this and pretend that if these
296 	 * fields are inconsistent across vCPUs, then it isn't worth
297 	 * trying to bring KVM up.
298 	 */
299 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
300 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
301 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
302 	/*
303 	 * We already refuse to boot CPUs that don't support our configured
304 	 * page size, so we can only detect mismatches for a page size other
305 	 * than the one we're currently using. Unfortunately, SoCs like this
306 	 * exist in the wild so, even though we don't like it, we'll have to go
307 	 * along with it and treat them as non-strict.
308 	 */
309 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
310 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
311 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
312 
313 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
314 	/* Linux shouldn't care about secure memory */
315 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
316 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
317 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
318 	/*
319 	 * Differing PARange is fine as long as all peripherals and memory are mapped
320 	 * within the minimum PARange of all CPUs
321 	 */
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
323 	ARM64_FTR_END,
324 };
325 
326 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
330 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
331 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
332 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
333 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
334 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
335 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
337 	ARM64_FTR_END,
338 };
339 
340 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
347 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
351 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
352 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
354 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
356 	ARM64_FTR_END,
357 };
358 
359 static const struct arm64_ftr_bits ftr_ctr[] = {
360 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
361 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
362 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
363 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
364 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
365 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
366 	/*
367 	 * Linux can handle differing I-cache policies. Userspace JITs will
368 	 * make use of *minLine.
369 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
370 	 */
371 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
372 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
373 	ARM64_FTR_END,
374 };
375 
376 static struct arm64_ftr_override __ro_after_init no_override = { };
377 
378 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
379 	.name		= "SYS_CTR_EL0",
380 	.ftr_bits	= ftr_ctr,
381 	.override	= &no_override,
382 };
383 
384 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
385 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
390 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
391 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
393 	ARM64_FTR_END,
394 };
395 
396 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
397 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
398 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
402 	/*
403 	 * We can instantiate multiple PMU instances with different levels
404 	 * of support.
405 	 */
406 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
407 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
408 	ARM64_FTR_END,
409 };
410 
411 static const struct arm64_ftr_bits ftr_mvfr2[] = {
412 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
414 	ARM64_FTR_END,
415 };
416 
417 static const struct arm64_ftr_bits ftr_dczid[] = {
418 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
419 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
420 	ARM64_FTR_END,
421 };
422 
423 static const struct arm64_ftr_bits ftr_gmid[] = {
424 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, SYS_GMID_EL1_BS_SHIFT, 4, 0),
425 	ARM64_FTR_END,
426 };
427 
428 static const struct arm64_ftr_bits ftr_id_isar0[] = {
429 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
430 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
431 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
432 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
433 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
434 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
435 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
436 	ARM64_FTR_END,
437 };
438 
439 static const struct arm64_ftr_bits ftr_id_isar5[] = {
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
444 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
446 	ARM64_FTR_END,
447 };
448 
449 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
457 
458 	/*
459 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
460 	 * external abort on speculative read. It is safe to assume that an
461 	 * SError might be generated than it will not be. Hence it has been
462 	 * classified as FTR_HIGHER_SAFE.
463 	 */
464 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
465 	ARM64_FTR_END,
466 };
467 
468 static const struct arm64_ftr_bits ftr_id_isar4[] = {
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
473 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
474 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
475 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
476 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
477 	ARM64_FTR_END,
478 };
479 
480 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
482 	ARM64_FTR_END,
483 };
484 
485 static const struct arm64_ftr_bits ftr_id_isar6[] = {
486 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
487 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
489 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
490 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
491 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
492 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
493 	ARM64_FTR_END,
494 };
495 
496 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
501 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
503 	ARM64_FTR_END,
504 };
505 
506 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
507 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
515 	ARM64_FTR_END,
516 };
517 
518 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
519 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
521 	ARM64_FTR_END,
522 };
523 
524 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
525 	/* [31:28] TraceFilt */
526 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
531 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
532 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
533 	ARM64_FTR_END,
534 };
535 
536 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
537 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
538 	ARM64_FTR_END,
539 };
540 
541 static const struct arm64_ftr_bits ftr_zcr[] = {
542 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
543 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
544 	ARM64_FTR_END,
545 };
546 
547 /*
548  * Common ftr bits for a 32bit register with all hidden, strict
549  * attributes, with 4bit feature fields and a default safe value of
550  * 0. Covers the following 32bit registers:
551  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
552  */
553 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
554 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
555 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
556 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
557 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
558 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
559 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
560 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
561 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
562 	ARM64_FTR_END,
563 };
564 
565 /* Table for a single 32bit feature value */
566 static const struct arm64_ftr_bits ftr_single32[] = {
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
568 	ARM64_FTR_END,
569 };
570 
571 static const struct arm64_ftr_bits ftr_raz[] = {
572 	ARM64_FTR_END,
573 };
574 
575 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr) {		\
576 		.sys_id = id,					\
577 		.reg = 	&(struct arm64_ftr_reg){		\
578 			.name = #id,				\
579 			.override = (ovr),			\
580 			.ftr_bits = &((table)[0]),		\
581 	}}
582 
583 #define ARM64_FTR_REG(id, table) ARM64_FTR_REG_OVERRIDE(id, table, &no_override)
584 
585 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
586 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
587 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
588 
589 static const struct __ftr_reg_entry {
590 	u32			sys_id;
591 	struct arm64_ftr_reg 	*reg;
592 } arm64_ftr_regs[] = {
593 
594 	/* Op1 = 0, CRn = 0, CRm = 1 */
595 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
596 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
597 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
598 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
599 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
600 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
601 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
602 
603 	/* Op1 = 0, CRn = 0, CRm = 2 */
604 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
605 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
606 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
607 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
608 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
609 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
610 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
611 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
612 
613 	/* Op1 = 0, CRn = 0, CRm = 3 */
614 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
615 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
616 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
617 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
618 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
619 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
620 
621 	/* Op1 = 0, CRn = 0, CRm = 4 */
622 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
623 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
624 			       &id_aa64pfr1_override),
625 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
626 
627 	/* Op1 = 0, CRn = 0, CRm = 5 */
628 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
629 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
630 
631 	/* Op1 = 0, CRn = 0, CRm = 6 */
632 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
633 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
634 			       &id_aa64isar1_override),
635 
636 	/* Op1 = 0, CRn = 0, CRm = 7 */
637 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
638 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
639 			       &id_aa64mmfr1_override),
640 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
641 
642 	/* Op1 = 0, CRn = 1, CRm = 2 */
643 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
644 
645 	/* Op1 = 1, CRn = 0, CRm = 0 */
646 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
647 
648 	/* Op1 = 3, CRn = 0, CRm = 0 */
649 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
650 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
651 
652 	/* Op1 = 3, CRn = 14, CRm = 0 */
653 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
654 };
655 
656 static int search_cmp_ftr_reg(const void *id, const void *regp)
657 {
658 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
659 }
660 
661 /*
662  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
663  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
664  * ascending order of sys_id, we use binary search to find a matching
665  * entry.
666  *
667  * returns - Upon success,  matching ftr_reg entry for id.
668  *         - NULL on failure. It is upto the caller to decide
669  *	     the impact of a failure.
670  */
671 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
672 {
673 	const struct __ftr_reg_entry *ret;
674 
675 	ret = bsearch((const void *)(unsigned long)sys_id,
676 			arm64_ftr_regs,
677 			ARRAY_SIZE(arm64_ftr_regs),
678 			sizeof(arm64_ftr_regs[0]),
679 			search_cmp_ftr_reg);
680 	if (ret)
681 		return ret->reg;
682 	return NULL;
683 }
684 
685 /*
686  * get_arm64_ftr_reg - Looks up a feature register entry using
687  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
688  *
689  * returns - Upon success,  matching ftr_reg entry for id.
690  *         - NULL on failure but with an WARN_ON().
691  */
692 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
693 {
694 	struct arm64_ftr_reg *reg;
695 
696 	reg = get_arm64_ftr_reg_nowarn(sys_id);
697 
698 	/*
699 	 * Requesting a non-existent register search is an error. Warn
700 	 * and let the caller handle it.
701 	 */
702 	WARN_ON(!reg);
703 	return reg;
704 }
705 
706 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
707 			       s64 ftr_val)
708 {
709 	u64 mask = arm64_ftr_mask(ftrp);
710 
711 	reg &= ~mask;
712 	reg |= (ftr_val << ftrp->shift) & mask;
713 	return reg;
714 }
715 
716 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
717 				s64 cur)
718 {
719 	s64 ret = 0;
720 
721 	switch (ftrp->type) {
722 	case FTR_EXACT:
723 		ret = ftrp->safe_val;
724 		break;
725 	case FTR_LOWER_SAFE:
726 		ret = min(new, cur);
727 		break;
728 	case FTR_HIGHER_OR_ZERO_SAFE:
729 		if (!cur || !new)
730 			break;
731 		fallthrough;
732 	case FTR_HIGHER_SAFE:
733 		ret = max(new, cur);
734 		break;
735 	default:
736 		BUG();
737 	}
738 
739 	return ret;
740 }
741 
742 static void __init sort_ftr_regs(void)
743 {
744 	unsigned int i;
745 
746 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
747 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
748 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
749 		unsigned int j = 0;
750 
751 		/*
752 		 * Features here must be sorted in descending order with respect
753 		 * to their shift values and should not overlap with each other.
754 		 */
755 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
756 			unsigned int width = ftr_reg->ftr_bits[j].width;
757 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
758 			unsigned int prev_shift;
759 
760 			WARN((shift  + width) > 64,
761 				"%s has invalid feature at shift %d\n",
762 				ftr_reg->name, shift);
763 
764 			/*
765 			 * Skip the first feature. There is nothing to
766 			 * compare against for now.
767 			 */
768 			if (j == 0)
769 				continue;
770 
771 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
772 			WARN((shift + width) > prev_shift,
773 				"%s has feature overlap at shift %d\n",
774 				ftr_reg->name, shift);
775 		}
776 
777 		/*
778 		 * Skip the first register. There is nothing to
779 		 * compare against for now.
780 		 */
781 		if (i == 0)
782 			continue;
783 		/*
784 		 * Registers here must be sorted in ascending order with respect
785 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
786 		 * to work correctly.
787 		 */
788 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
789 	}
790 }
791 
792 /*
793  * Initialise the CPU feature register from Boot CPU values.
794  * Also initiliases the strict_mask for the register.
795  * Any bits that are not covered by an arm64_ftr_bits entry are considered
796  * RES0 for the system-wide value, and must strictly match.
797  */
798 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
799 {
800 	u64 val = 0;
801 	u64 strict_mask = ~0x0ULL;
802 	u64 user_mask = 0;
803 	u64 valid_mask = 0;
804 
805 	const struct arm64_ftr_bits *ftrp;
806 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
807 
808 	if (!reg)
809 		return;
810 
811 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
812 		u64 ftr_mask = arm64_ftr_mask(ftrp);
813 		s64 ftr_new = arm64_ftr_value(ftrp, new);
814 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
815 
816 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
817 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
818 			char *str = NULL;
819 
820 			if (ftr_ovr != tmp) {
821 				/* Unsafe, remove the override */
822 				reg->override->mask &= ~ftr_mask;
823 				reg->override->val &= ~ftr_mask;
824 				tmp = ftr_ovr;
825 				str = "ignoring override";
826 			} else if (ftr_new != tmp) {
827 				/* Override was valid */
828 				ftr_new = tmp;
829 				str = "forced";
830 			} else if (ftr_ovr == tmp) {
831 				/* Override was the safe value */
832 				str = "already set";
833 			}
834 
835 			if (str)
836 				pr_warn("%s[%d:%d]: %s to %llx\n",
837 					reg->name,
838 					ftrp->shift + ftrp->width - 1,
839 					ftrp->shift, str, tmp);
840 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
841 			reg->override->val &= ~ftr_mask;
842 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
843 				reg->name,
844 				ftrp->shift + ftrp->width - 1,
845 				ftrp->shift);
846 		}
847 
848 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
849 
850 		valid_mask |= ftr_mask;
851 		if (!ftrp->strict)
852 			strict_mask &= ~ftr_mask;
853 		if (ftrp->visible)
854 			user_mask |= ftr_mask;
855 		else
856 			reg->user_val = arm64_ftr_set_value(ftrp,
857 							    reg->user_val,
858 							    ftrp->safe_val);
859 	}
860 
861 	val &= valid_mask;
862 
863 	reg->sys_val = val;
864 	reg->strict_mask = strict_mask;
865 	reg->user_mask = user_mask;
866 }
867 
868 extern const struct arm64_cpu_capabilities arm64_errata[];
869 static const struct arm64_cpu_capabilities arm64_features[];
870 
871 static void __init
872 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
873 {
874 	for (; caps->matches; caps++) {
875 		if (WARN(caps->capability >= ARM64_NCAPS,
876 			"Invalid capability %d\n", caps->capability))
877 			continue;
878 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
879 			"Duplicate entry for capability %d\n",
880 			caps->capability))
881 			continue;
882 		cpu_hwcaps_ptrs[caps->capability] = caps;
883 	}
884 }
885 
886 static void __init init_cpu_hwcaps_indirect_list(void)
887 {
888 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
889 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
890 }
891 
892 static void __init setup_boot_cpu_capabilities(void);
893 
894 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
895 {
896 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
897 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
898 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
899 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
900 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
901 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
902 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
903 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
904 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
905 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
906 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
907 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
908 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
909 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
910 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
911 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
912 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
913 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
914 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
915 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
916 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
917 }
918 
919 void __init init_cpu_features(struct cpuinfo_arm64 *info)
920 {
921 	/* Before we start using the tables, make sure it is sorted */
922 	sort_ftr_regs();
923 
924 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
925 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
926 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
927 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
928 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
929 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
930 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
931 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
932 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
933 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
934 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
935 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
936 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
937 
938 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
939 		init_32bit_cpu_features(&info->aarch32);
940 
941 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
942 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
943 		sve_init_vq_map();
944 	}
945 
946 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
947 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
948 
949 	/*
950 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
951 	 * before we handle the boot CPU below.
952 	 */
953 	init_cpu_hwcaps_indirect_list();
954 
955 	/*
956 	 * Detect and enable early CPU capabilities based on the boot CPU,
957 	 * after we have initialised the CPU feature infrastructure.
958 	 */
959 	setup_boot_cpu_capabilities();
960 }
961 
962 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
963 {
964 	const struct arm64_ftr_bits *ftrp;
965 
966 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
967 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
968 		s64 ftr_new = arm64_ftr_value(ftrp, new);
969 
970 		if (ftr_cur == ftr_new)
971 			continue;
972 		/* Find a safe value */
973 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
974 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
975 	}
976 
977 }
978 
979 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
980 {
981 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
982 
983 	if (!regp)
984 		return 0;
985 
986 	update_cpu_ftr_reg(regp, val);
987 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
988 		return 0;
989 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
990 			regp->name, boot, cpu, val);
991 	return 1;
992 }
993 
994 static void relax_cpu_ftr_reg(u32 sys_id, int field)
995 {
996 	const struct arm64_ftr_bits *ftrp;
997 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
998 
999 	if (!regp)
1000 		return;
1001 
1002 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1003 		if (ftrp->shift == field) {
1004 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1005 			break;
1006 		}
1007 	}
1008 
1009 	/* Bogus field? */
1010 	WARN_ON(!ftrp->width);
1011 }
1012 
1013 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1014 					 struct cpuinfo_arm64 *boot)
1015 {
1016 	static bool boot_cpu_32bit_regs_overridden = false;
1017 
1018 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1019 		return;
1020 
1021 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1022 		return;
1023 
1024 	boot->aarch32 = info->aarch32;
1025 	init_32bit_cpu_features(&boot->aarch32);
1026 	boot_cpu_32bit_regs_overridden = true;
1027 }
1028 
1029 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1030 				     struct cpuinfo_32bit *boot)
1031 {
1032 	int taint = 0;
1033 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1034 
1035 	/*
1036 	 * If we don't have AArch32 at EL1, then relax the strictness of
1037 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1038 	 */
1039 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1040 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1041 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1042 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1043 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1044 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1045 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1046 	}
1047 
1048 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1049 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1050 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1051 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1052 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1053 				      info->reg_id_isar0, boot->reg_id_isar0);
1054 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1055 				      info->reg_id_isar1, boot->reg_id_isar1);
1056 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1057 				      info->reg_id_isar2, boot->reg_id_isar2);
1058 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1059 				      info->reg_id_isar3, boot->reg_id_isar3);
1060 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1061 				      info->reg_id_isar4, boot->reg_id_isar4);
1062 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1063 				      info->reg_id_isar5, boot->reg_id_isar5);
1064 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1065 				      info->reg_id_isar6, boot->reg_id_isar6);
1066 
1067 	/*
1068 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1069 	 * ACTLR formats could differ across CPUs and therefore would have to
1070 	 * be trapped for virtualization anyway.
1071 	 */
1072 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1073 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1074 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1075 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1076 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1077 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1078 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1079 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1080 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1081 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1082 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1083 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1084 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1085 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1086 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1087 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1088 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1089 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1090 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1091 				      info->reg_mvfr0, boot->reg_mvfr0);
1092 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1093 				      info->reg_mvfr1, boot->reg_mvfr1);
1094 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1095 				      info->reg_mvfr2, boot->reg_mvfr2);
1096 
1097 	return taint;
1098 }
1099 
1100 /*
1101  * Update system wide CPU feature registers with the values from a
1102  * non-boot CPU. Also performs SANITY checks to make sure that there
1103  * aren't any insane variations from that of the boot CPU.
1104  */
1105 void update_cpu_features(int cpu,
1106 			 struct cpuinfo_arm64 *info,
1107 			 struct cpuinfo_arm64 *boot)
1108 {
1109 	int taint = 0;
1110 
1111 	/*
1112 	 * The kernel can handle differing I-cache policies, but otherwise
1113 	 * caches should look identical. Userspace JITs will make use of
1114 	 * *minLine.
1115 	 */
1116 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1117 				      info->reg_ctr, boot->reg_ctr);
1118 
1119 	/*
1120 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1121 	 * could result in too much or too little memory being zeroed if a
1122 	 * process is preempted and migrated between CPUs.
1123 	 */
1124 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1125 				      info->reg_dczid, boot->reg_dczid);
1126 
1127 	/* If different, timekeeping will be broken (especially with KVM) */
1128 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1129 				      info->reg_cntfrq, boot->reg_cntfrq);
1130 
1131 	/*
1132 	 * The kernel uses self-hosted debug features and expects CPUs to
1133 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1134 	 * and BRPs to be identical.
1135 	 * ID_AA64DFR1 is currently RES0.
1136 	 */
1137 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1138 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1139 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1140 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1141 	/*
1142 	 * Even in big.LITTLE, processors should be identical instruction-set
1143 	 * wise.
1144 	 */
1145 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1146 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1147 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1148 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1149 
1150 	/*
1151 	 * Differing PARange support is fine as long as all peripherals and
1152 	 * memory are mapped within the minimum PARange of all CPUs.
1153 	 * Linux should not care about secure memory.
1154 	 */
1155 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1156 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1157 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1158 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1159 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1160 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1161 
1162 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1163 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1164 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1165 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1166 
1167 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1168 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1169 
1170 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1171 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1172 					info->reg_zcr, boot->reg_zcr);
1173 
1174 		/* Probe vector lengths, unless we already gave up on SVE */
1175 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1176 		    !system_capabilities_finalized())
1177 			sve_update_vq_map();
1178 	}
1179 
1180 	/*
1181 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1182 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1183 	 * value is the same on all CPUs.
1184 	 */
1185 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1186 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1187 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1188 					      info->reg_gmid, boot->reg_gmid);
1189 	}
1190 
1191 	/*
1192 	 * If we don't have AArch32 at all then skip the checks entirely
1193 	 * as the register values may be UNKNOWN and we're not going to be
1194 	 * using them for anything.
1195 	 *
1196 	 * This relies on a sanitised view of the AArch64 ID registers
1197 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1198 	 */
1199 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1200 		lazy_init_32bit_cpu_features(info, boot);
1201 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1202 						   &boot->aarch32);
1203 	}
1204 
1205 	/*
1206 	 * Mismatched CPU features are a recipe for disaster. Don't even
1207 	 * pretend to support them.
1208 	 */
1209 	if (taint) {
1210 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1211 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1212 	}
1213 }
1214 
1215 u64 read_sanitised_ftr_reg(u32 id)
1216 {
1217 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1218 
1219 	if (!regp)
1220 		return 0;
1221 	return regp->sys_val;
1222 }
1223 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1224 
1225 #define read_sysreg_case(r)	\
1226 	case r:		val = read_sysreg_s(r); break;
1227 
1228 /*
1229  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1230  * Read the system register on the current CPU
1231  */
1232 u64 __read_sysreg_by_encoding(u32 sys_id)
1233 {
1234 	struct arm64_ftr_reg *regp;
1235 	u64 val;
1236 
1237 	switch (sys_id) {
1238 	read_sysreg_case(SYS_ID_PFR0_EL1);
1239 	read_sysreg_case(SYS_ID_PFR1_EL1);
1240 	read_sysreg_case(SYS_ID_PFR2_EL1);
1241 	read_sysreg_case(SYS_ID_DFR0_EL1);
1242 	read_sysreg_case(SYS_ID_DFR1_EL1);
1243 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1244 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1245 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1246 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1247 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1248 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1249 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1250 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1251 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1252 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1253 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1254 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1255 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1256 	read_sysreg_case(SYS_MVFR0_EL1);
1257 	read_sysreg_case(SYS_MVFR1_EL1);
1258 	read_sysreg_case(SYS_MVFR2_EL1);
1259 
1260 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1261 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1262 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1263 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1264 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1265 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1266 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1267 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1268 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1269 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1270 
1271 	read_sysreg_case(SYS_CNTFRQ_EL0);
1272 	read_sysreg_case(SYS_CTR_EL0);
1273 	read_sysreg_case(SYS_DCZID_EL0);
1274 
1275 	default:
1276 		BUG();
1277 		return 0;
1278 	}
1279 
1280 	regp  = get_arm64_ftr_reg(sys_id);
1281 	if (regp) {
1282 		val &= ~regp->override->mask;
1283 		val |= (regp->override->val & regp->override->mask);
1284 	}
1285 
1286 	return val;
1287 }
1288 
1289 #include <linux/irqchip/arm-gic-v3.h>
1290 
1291 static bool
1292 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1293 {
1294 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1295 
1296 	return val >= entry->min_field_value;
1297 }
1298 
1299 static bool
1300 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1301 {
1302 	u64 val;
1303 
1304 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1305 	if (scope == SCOPE_SYSTEM)
1306 		val = read_sanitised_ftr_reg(entry->sys_reg);
1307 	else
1308 		val = __read_sysreg_by_encoding(entry->sys_reg);
1309 
1310 	return feature_matches(val, entry);
1311 }
1312 
1313 const struct cpumask *system_32bit_el0_cpumask(void)
1314 {
1315 	if (!system_supports_32bit_el0())
1316 		return cpu_none_mask;
1317 
1318 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1319 		return cpu_32bit_el0_mask;
1320 
1321 	return cpu_possible_mask;
1322 }
1323 
1324 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1325 {
1326 	if (!has_cpuid_feature(entry, scope))
1327 		return allow_mismatched_32bit_el0;
1328 
1329 	if (scope == SCOPE_SYSTEM)
1330 		pr_info("detected: 32-bit EL0 Support\n");
1331 
1332 	return true;
1333 }
1334 
1335 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1336 {
1337 	bool has_sre;
1338 
1339 	if (!has_cpuid_feature(entry, scope))
1340 		return false;
1341 
1342 	has_sre = gic_enable_sre();
1343 	if (!has_sre)
1344 		pr_warn_once("%s present but disabled by higher exception level\n",
1345 			     entry->desc);
1346 
1347 	return has_sre;
1348 }
1349 
1350 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1351 {
1352 	u32 midr = read_cpuid_id();
1353 
1354 	/* Cavium ThunderX pass 1.x and 2.x */
1355 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1356 		MIDR_CPU_VAR_REV(0, 0),
1357 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1358 }
1359 
1360 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1361 {
1362 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1363 
1364 	return cpuid_feature_extract_signed_field(pfr0,
1365 					ID_AA64PFR0_FP_SHIFT) < 0;
1366 }
1367 
1368 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1369 			  int scope)
1370 {
1371 	u64 ctr;
1372 
1373 	if (scope == SCOPE_SYSTEM)
1374 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1375 	else
1376 		ctr = read_cpuid_effective_cachetype();
1377 
1378 	return ctr & BIT(CTR_IDC_SHIFT);
1379 }
1380 
1381 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1382 {
1383 	/*
1384 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1385 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1386 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1387 	 * value.
1388 	 */
1389 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1390 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1391 }
1392 
1393 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1394 			  int scope)
1395 {
1396 	u64 ctr;
1397 
1398 	if (scope == SCOPE_SYSTEM)
1399 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1400 	else
1401 		ctr = read_cpuid_cachetype();
1402 
1403 	return ctr & BIT(CTR_DIC_SHIFT);
1404 }
1405 
1406 static bool __maybe_unused
1407 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1408 {
1409 	/*
1410 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1411 	 * may share TLB entries with a CPU stuck in the crashed
1412 	 * kernel.
1413 	 */
1414 	if (is_kdump_kernel())
1415 		return false;
1416 
1417 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1418 		return false;
1419 
1420 	return has_cpuid_feature(entry, scope);
1421 }
1422 
1423 /*
1424  * This check is triggered during the early boot before the cpufeature
1425  * is initialised. Checking the status on the local CPU allows the boot
1426  * CPU to detect the need for non-global mappings and thus avoiding a
1427  * pagetable re-write after all the CPUs are booted. This check will be
1428  * anyway run on individual CPUs, allowing us to get the consistent
1429  * state once the SMP CPUs are up and thus make the switch to non-global
1430  * mappings if required.
1431  */
1432 bool kaslr_requires_kpti(void)
1433 {
1434 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1435 		return false;
1436 
1437 	/*
1438 	 * E0PD does a similar job to KPTI so can be used instead
1439 	 * where available.
1440 	 */
1441 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1442 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1443 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1444 						ID_AA64MMFR2_E0PD_SHIFT))
1445 			return false;
1446 	}
1447 
1448 	/*
1449 	 * Systems affected by Cavium erratum 24756 are incompatible
1450 	 * with KPTI.
1451 	 */
1452 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1453 		extern const struct midr_range cavium_erratum_27456_cpus[];
1454 
1455 		if (is_midr_in_range_list(read_cpuid_id(),
1456 					  cavium_erratum_27456_cpus))
1457 			return false;
1458 	}
1459 
1460 	return kaslr_offset() > 0;
1461 }
1462 
1463 static bool __meltdown_safe = true;
1464 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1465 
1466 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1467 				int scope)
1468 {
1469 	/* List of CPUs that are not vulnerable and don't need KPTI */
1470 	static const struct midr_range kpti_safe_list[] = {
1471 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1472 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1473 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1474 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1475 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1476 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1477 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1478 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1479 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1480 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1481 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1482 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1483 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1484 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1485 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1486 		{ /* sentinel */ }
1487 	};
1488 	char const *str = "kpti command line option";
1489 	bool meltdown_safe;
1490 
1491 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1492 
1493 	/* Defer to CPU feature registers */
1494 	if (has_cpuid_feature(entry, scope))
1495 		meltdown_safe = true;
1496 
1497 	if (!meltdown_safe)
1498 		__meltdown_safe = false;
1499 
1500 	/*
1501 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1502 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1503 	 * ends as well as you might imagine. Don't even try.
1504 	 */
1505 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1506 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1507 		__kpti_forced = -1;
1508 	}
1509 
1510 	/* Useful for KASLR robustness */
1511 	if (kaslr_requires_kpti()) {
1512 		if (!__kpti_forced) {
1513 			str = "KASLR";
1514 			__kpti_forced = 1;
1515 		}
1516 	}
1517 
1518 	if (cpu_mitigations_off() && !__kpti_forced) {
1519 		str = "mitigations=off";
1520 		__kpti_forced = -1;
1521 	}
1522 
1523 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1524 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1525 		return false;
1526 	}
1527 
1528 	/* Forced? */
1529 	if (__kpti_forced) {
1530 		pr_info_once("kernel page table isolation forced %s by %s\n",
1531 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1532 		return __kpti_forced > 0;
1533 	}
1534 
1535 	return !meltdown_safe;
1536 }
1537 
1538 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1539 static void __nocfi
1540 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1541 {
1542 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1543 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1544 	kpti_remap_fn *remap_fn;
1545 
1546 	int cpu = smp_processor_id();
1547 
1548 	/*
1549 	 * We don't need to rewrite the page-tables if either we've done
1550 	 * it already or we have KASLR enabled and therefore have not
1551 	 * created any global mappings at all.
1552 	 */
1553 	if (arm64_use_ng_mappings)
1554 		return;
1555 
1556 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1557 
1558 	cpu_install_idmap();
1559 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1560 	cpu_uninstall_idmap();
1561 
1562 	if (!cpu)
1563 		arm64_use_ng_mappings = true;
1564 
1565 	return;
1566 }
1567 #else
1568 static void
1569 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1570 {
1571 }
1572 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1573 
1574 static int __init parse_kpti(char *str)
1575 {
1576 	bool enabled;
1577 	int ret = strtobool(str, &enabled);
1578 
1579 	if (ret)
1580 		return ret;
1581 
1582 	__kpti_forced = enabled ? 1 : -1;
1583 	return 0;
1584 }
1585 early_param("kpti", parse_kpti);
1586 
1587 #ifdef CONFIG_ARM64_HW_AFDBM
1588 static inline void __cpu_enable_hw_dbm(void)
1589 {
1590 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1591 
1592 	write_sysreg(tcr, tcr_el1);
1593 	isb();
1594 	local_flush_tlb_all();
1595 }
1596 
1597 static bool cpu_has_broken_dbm(void)
1598 {
1599 	/* List of CPUs which have broken DBM support. */
1600 	static const struct midr_range cpus[] = {
1601 #ifdef CONFIG_ARM64_ERRATUM_1024718
1602 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1603 		/* Kryo4xx Silver (rdpe => r1p0) */
1604 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1605 #endif
1606 		{},
1607 	};
1608 
1609 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1610 }
1611 
1612 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1613 {
1614 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1615 	       !cpu_has_broken_dbm();
1616 }
1617 
1618 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1619 {
1620 	if (cpu_can_use_dbm(cap))
1621 		__cpu_enable_hw_dbm();
1622 }
1623 
1624 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1625 		       int __unused)
1626 {
1627 	static bool detected = false;
1628 	/*
1629 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1630 	 * run a mix of CPUs with and without the feature. So, we
1631 	 * unconditionally enable the capability to allow any late CPU
1632 	 * to use the feature. We only enable the control bits on the
1633 	 * CPU, if it actually supports.
1634 	 *
1635 	 * We have to make sure we print the "feature" detection only
1636 	 * when at least one CPU actually uses it. So check if this CPU
1637 	 * can actually use it and print the message exactly once.
1638 	 *
1639 	 * This is safe as all CPUs (including secondary CPUs - due to the
1640 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1641 	 * goes through the "matches" check exactly once. Also if a CPU
1642 	 * matches the criteria, it is guaranteed that the CPU will turn
1643 	 * the DBM on, as the capability is unconditionally enabled.
1644 	 */
1645 	if (!detected && cpu_can_use_dbm(cap)) {
1646 		detected = true;
1647 		pr_info("detected: Hardware dirty bit management\n");
1648 	}
1649 
1650 	return true;
1651 }
1652 
1653 #endif
1654 
1655 #ifdef CONFIG_ARM64_AMU_EXTN
1656 
1657 /*
1658  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1659  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1660  * information regarding all the events that it supports. When a CPU bit is
1661  * set in the cpumask, the user of this feature can only rely on the presence
1662  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1663  * counters are enabled or access to these counters is enabled by code
1664  * executed at higher exception levels (firmware).
1665  */
1666 static struct cpumask amu_cpus __read_mostly;
1667 
1668 bool cpu_has_amu_feat(int cpu)
1669 {
1670 	return cpumask_test_cpu(cpu, &amu_cpus);
1671 }
1672 
1673 int get_cpu_with_amu_feat(void)
1674 {
1675 	return cpumask_any(&amu_cpus);
1676 }
1677 
1678 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1679 {
1680 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1681 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1682 			smp_processor_id());
1683 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1684 		update_freq_counters_refs();
1685 	}
1686 }
1687 
1688 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1689 		    int __unused)
1690 {
1691 	/*
1692 	 * The AMU extension is a non-conflicting feature: the kernel can
1693 	 * safely run a mix of CPUs with and without support for the
1694 	 * activity monitors extension. Therefore, unconditionally enable
1695 	 * the capability to allow any late CPU to use the feature.
1696 	 *
1697 	 * With this feature unconditionally enabled, the cpu_enable
1698 	 * function will be called for all CPUs that match the criteria,
1699 	 * including secondary and hotplugged, marking this feature as
1700 	 * present on that respective CPU. The enable function will also
1701 	 * print a detection message.
1702 	 */
1703 
1704 	return true;
1705 }
1706 #else
1707 int get_cpu_with_amu_feat(void)
1708 {
1709 	return nr_cpu_ids;
1710 }
1711 #endif
1712 
1713 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1714 {
1715 	return is_kernel_in_hyp_mode();
1716 }
1717 
1718 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1719 {
1720 	/*
1721 	 * Copy register values that aren't redirected by hardware.
1722 	 *
1723 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1724 	 * this value to tpidr_el2 before we patch the code. Once we've done
1725 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1726 	 * do anything here.
1727 	 */
1728 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1729 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1730 }
1731 
1732 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1733 {
1734 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1735 
1736 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1737 	WARN_ON(val & (7 << 27 | 7 << 21));
1738 }
1739 
1740 #ifdef CONFIG_ARM64_PAN
1741 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1742 {
1743 	/*
1744 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1745 	 * is discarded once we return from the exception.
1746 	 */
1747 	WARN_ON_ONCE(in_interrupt());
1748 
1749 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1750 	set_pstate_pan(1);
1751 }
1752 #endif /* CONFIG_ARM64_PAN */
1753 
1754 #ifdef CONFIG_ARM64_RAS_EXTN
1755 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1756 {
1757 	/* Firmware may have left a deferred SError in this register. */
1758 	write_sysreg_s(0, SYS_DISR_EL1);
1759 }
1760 #endif /* CONFIG_ARM64_RAS_EXTN */
1761 
1762 #ifdef CONFIG_ARM64_PTR_AUTH
1763 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1764 {
1765 	int boot_val, sec_val;
1766 
1767 	/* We don't expect to be called with SCOPE_SYSTEM */
1768 	WARN_ON(scope == SCOPE_SYSTEM);
1769 	/*
1770 	 * The ptr-auth feature levels are not intercompatible with lower
1771 	 * levels. Hence we must match ptr-auth feature level of the secondary
1772 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1773 	 * from the sanitised register whereas direct register read is done for
1774 	 * the secondary CPUs.
1775 	 * The sanitised feature state is guaranteed to match that of the
1776 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1777 	 * a chance to update the state, with the capability.
1778 	 */
1779 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1780 					       entry->field_pos, entry->sign);
1781 	if (scope & SCOPE_BOOT_CPU)
1782 		return boot_val >= entry->min_field_value;
1783 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1784 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1785 					      entry->field_pos, entry->sign);
1786 	return sec_val == boot_val;
1787 }
1788 
1789 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1790 				     int scope)
1791 {
1792 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1793 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1794 }
1795 
1796 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1797 			     int __unused)
1798 {
1799 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1800 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1801 }
1802 #endif /* CONFIG_ARM64_PTR_AUTH */
1803 
1804 #ifdef CONFIG_ARM64_E0PD
1805 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1806 {
1807 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1808 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1809 }
1810 #endif /* CONFIG_ARM64_E0PD */
1811 
1812 #ifdef CONFIG_ARM64_PSEUDO_NMI
1813 static bool enable_pseudo_nmi;
1814 
1815 static int __init early_enable_pseudo_nmi(char *p)
1816 {
1817 	return strtobool(p, &enable_pseudo_nmi);
1818 }
1819 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1820 
1821 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1822 				   int scope)
1823 {
1824 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1825 }
1826 #endif
1827 
1828 #ifdef CONFIG_ARM64_BTI
1829 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1830 {
1831 	/*
1832 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1833 	 * function entry points using BR is a requirement for
1834 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1835 	 * So, be strict and forbid other BRs using other registers to
1836 	 * jump onto a PACIxSP instruction:
1837 	 */
1838 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1839 	isb();
1840 }
1841 #endif /* CONFIG_ARM64_BTI */
1842 
1843 #ifdef CONFIG_ARM64_MTE
1844 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1845 {
1846 	/*
1847 	 * Clear the tags in the zero page. This needs to be done via the
1848 	 * linear map which has the Tagged attribute.
1849 	 */
1850 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1851 		mte_clear_page_tags(lm_alias(empty_zero_page));
1852 
1853 	kasan_init_hw_tags_cpu();
1854 }
1855 #endif /* CONFIG_ARM64_MTE */
1856 
1857 #ifdef CONFIG_KVM
1858 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1859 {
1860 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1861 		return false;
1862 
1863 	if (is_kernel_in_hyp_mode()) {
1864 		pr_warn("Protected KVM not available with VHE\n");
1865 		return false;
1866 	}
1867 
1868 	return true;
1869 }
1870 #endif /* CONFIG_KVM */
1871 
1872 /* Internal helper functions to match cpu capability type */
1873 static bool
1874 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1875 {
1876 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1877 }
1878 
1879 static bool
1880 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1881 {
1882 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1883 }
1884 
1885 static bool
1886 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1887 {
1888 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1889 }
1890 
1891 static const struct arm64_cpu_capabilities arm64_features[] = {
1892 	{
1893 		.desc = "GIC system register CPU interface",
1894 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1895 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1896 		.matches = has_useable_gicv3_cpuif,
1897 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1898 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1899 		.sign = FTR_UNSIGNED,
1900 		.min_field_value = 1,
1901 	},
1902 #ifdef CONFIG_ARM64_PAN
1903 	{
1904 		.desc = "Privileged Access Never",
1905 		.capability = ARM64_HAS_PAN,
1906 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1907 		.matches = has_cpuid_feature,
1908 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1909 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1910 		.sign = FTR_UNSIGNED,
1911 		.min_field_value = 1,
1912 		.cpu_enable = cpu_enable_pan,
1913 	},
1914 #endif /* CONFIG_ARM64_PAN */
1915 #ifdef CONFIG_ARM64_EPAN
1916 	{
1917 		.desc = "Enhanced Privileged Access Never",
1918 		.capability = ARM64_HAS_EPAN,
1919 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1920 		.matches = has_cpuid_feature,
1921 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1922 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1923 		.sign = FTR_UNSIGNED,
1924 		.min_field_value = 3,
1925 	},
1926 #endif /* CONFIG_ARM64_EPAN */
1927 #ifdef CONFIG_ARM64_LSE_ATOMICS
1928 	{
1929 		.desc = "LSE atomic instructions",
1930 		.capability = ARM64_HAS_LSE_ATOMICS,
1931 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1932 		.matches = has_cpuid_feature,
1933 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1934 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1935 		.sign = FTR_UNSIGNED,
1936 		.min_field_value = 2,
1937 	},
1938 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1939 	{
1940 		.desc = "Software prefetching using PRFM",
1941 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1942 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1943 		.matches = has_no_hw_prefetch,
1944 	},
1945 	{
1946 		.desc = "Virtualization Host Extensions",
1947 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1948 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1949 		.matches = runs_at_el2,
1950 		.cpu_enable = cpu_copy_el2regs,
1951 	},
1952 	{
1953 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
1954 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1955 		.matches = has_32bit_el0,
1956 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1957 		.sign = FTR_UNSIGNED,
1958 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1959 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1960 	},
1961 #ifdef CONFIG_KVM
1962 	{
1963 		.desc = "32-bit EL1 Support",
1964 		.capability = ARM64_HAS_32BIT_EL1,
1965 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1966 		.matches = has_cpuid_feature,
1967 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1968 		.sign = FTR_UNSIGNED,
1969 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
1970 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
1971 	},
1972 	{
1973 		.desc = "Protected KVM",
1974 		.capability = ARM64_KVM_PROTECTED_MODE,
1975 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1976 		.matches = is_kvm_protected_mode,
1977 	},
1978 #endif
1979 	{
1980 		.desc = "Kernel page table isolation (KPTI)",
1981 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1982 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1983 		/*
1984 		 * The ID feature fields below are used to indicate that
1985 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1986 		 * more details.
1987 		 */
1988 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1989 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1990 		.min_field_value = 1,
1991 		.matches = unmap_kernel_at_el0,
1992 		.cpu_enable = kpti_install_ng_mappings,
1993 	},
1994 	{
1995 		/* FP/SIMD is not implemented */
1996 		.capability = ARM64_HAS_NO_FPSIMD,
1997 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1998 		.min_field_value = 0,
1999 		.matches = has_no_fpsimd,
2000 	},
2001 #ifdef CONFIG_ARM64_PMEM
2002 	{
2003 		.desc = "Data cache clean to Point of Persistence",
2004 		.capability = ARM64_HAS_DCPOP,
2005 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2006 		.matches = has_cpuid_feature,
2007 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2008 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2009 		.min_field_value = 1,
2010 	},
2011 	{
2012 		.desc = "Data cache clean to Point of Deep Persistence",
2013 		.capability = ARM64_HAS_DCPODP,
2014 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2015 		.matches = has_cpuid_feature,
2016 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2017 		.sign = FTR_UNSIGNED,
2018 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2019 		.min_field_value = 2,
2020 	},
2021 #endif
2022 #ifdef CONFIG_ARM64_SVE
2023 	{
2024 		.desc = "Scalable Vector Extension",
2025 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2026 		.capability = ARM64_SVE,
2027 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2028 		.sign = FTR_UNSIGNED,
2029 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2030 		.min_field_value = ID_AA64PFR0_SVE,
2031 		.matches = has_cpuid_feature,
2032 		.cpu_enable = sve_kernel_enable,
2033 	},
2034 #endif /* CONFIG_ARM64_SVE */
2035 #ifdef CONFIG_ARM64_RAS_EXTN
2036 	{
2037 		.desc = "RAS Extension Support",
2038 		.capability = ARM64_HAS_RAS_EXTN,
2039 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2040 		.matches = has_cpuid_feature,
2041 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2042 		.sign = FTR_UNSIGNED,
2043 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2044 		.min_field_value = ID_AA64PFR0_RAS_V1,
2045 		.cpu_enable = cpu_clear_disr,
2046 	},
2047 #endif /* CONFIG_ARM64_RAS_EXTN */
2048 #ifdef CONFIG_ARM64_AMU_EXTN
2049 	{
2050 		/*
2051 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2052 		 * Therefore, don't provide .desc as we don't want the detection
2053 		 * message to be shown until at least one CPU is detected to
2054 		 * support the feature.
2055 		 */
2056 		.capability = ARM64_HAS_AMU_EXTN,
2057 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2058 		.matches = has_amu,
2059 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2060 		.sign = FTR_UNSIGNED,
2061 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2062 		.min_field_value = ID_AA64PFR0_AMU,
2063 		.cpu_enable = cpu_amu_enable,
2064 	},
2065 #endif /* CONFIG_ARM64_AMU_EXTN */
2066 	{
2067 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2068 		.capability = ARM64_HAS_CACHE_IDC,
2069 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2070 		.matches = has_cache_idc,
2071 		.cpu_enable = cpu_emulate_effective_ctr,
2072 	},
2073 	{
2074 		.desc = "Instruction cache invalidation not required for I/D coherence",
2075 		.capability = ARM64_HAS_CACHE_DIC,
2076 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2077 		.matches = has_cache_dic,
2078 	},
2079 	{
2080 		.desc = "Stage-2 Force Write-Back",
2081 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2082 		.capability = ARM64_HAS_STAGE2_FWB,
2083 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2084 		.sign = FTR_UNSIGNED,
2085 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2086 		.min_field_value = 1,
2087 		.matches = has_cpuid_feature,
2088 		.cpu_enable = cpu_has_fwb,
2089 	},
2090 	{
2091 		.desc = "ARMv8.4 Translation Table Level",
2092 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2093 		.capability = ARM64_HAS_ARMv8_4_TTL,
2094 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2095 		.sign = FTR_UNSIGNED,
2096 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2097 		.min_field_value = 1,
2098 		.matches = has_cpuid_feature,
2099 	},
2100 	{
2101 		.desc = "TLB range maintenance instructions",
2102 		.capability = ARM64_HAS_TLB_RANGE,
2103 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2104 		.matches = has_cpuid_feature,
2105 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2106 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
2107 		.sign = FTR_UNSIGNED,
2108 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
2109 	},
2110 #ifdef CONFIG_ARM64_HW_AFDBM
2111 	{
2112 		/*
2113 		 * Since we turn this on always, we don't want the user to
2114 		 * think that the feature is available when it may not be.
2115 		 * So hide the description.
2116 		 *
2117 		 * .desc = "Hardware pagetable Dirty Bit Management",
2118 		 *
2119 		 */
2120 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2121 		.capability = ARM64_HW_DBM,
2122 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2123 		.sign = FTR_UNSIGNED,
2124 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2125 		.min_field_value = 2,
2126 		.matches = has_hw_dbm,
2127 		.cpu_enable = cpu_enable_hw_dbm,
2128 	},
2129 #endif
2130 	{
2131 		.desc = "CRC32 instructions",
2132 		.capability = ARM64_HAS_CRC32,
2133 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2134 		.matches = has_cpuid_feature,
2135 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2136 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2137 		.min_field_value = 1,
2138 	},
2139 	{
2140 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2141 		.capability = ARM64_SSBS,
2142 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2143 		.matches = has_cpuid_feature,
2144 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2145 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2146 		.sign = FTR_UNSIGNED,
2147 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2148 	},
2149 #ifdef CONFIG_ARM64_CNP
2150 	{
2151 		.desc = "Common not Private translations",
2152 		.capability = ARM64_HAS_CNP,
2153 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2154 		.matches = has_useable_cnp,
2155 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2156 		.sign = FTR_UNSIGNED,
2157 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2158 		.min_field_value = 1,
2159 		.cpu_enable = cpu_enable_cnp,
2160 	},
2161 #endif
2162 	{
2163 		.desc = "Speculation barrier (SB)",
2164 		.capability = ARM64_HAS_SB,
2165 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2166 		.matches = has_cpuid_feature,
2167 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2168 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2169 		.sign = FTR_UNSIGNED,
2170 		.min_field_value = 1,
2171 	},
2172 #ifdef CONFIG_ARM64_PTR_AUTH
2173 	{
2174 		.desc = "Address authentication (architected algorithm)",
2175 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2176 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2177 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2178 		.sign = FTR_UNSIGNED,
2179 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2180 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2181 		.matches = has_address_auth_cpucap,
2182 	},
2183 	{
2184 		.desc = "Address authentication (IMP DEF algorithm)",
2185 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2186 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2187 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2188 		.sign = FTR_UNSIGNED,
2189 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2190 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2191 		.matches = has_address_auth_cpucap,
2192 	},
2193 	{
2194 		.capability = ARM64_HAS_ADDRESS_AUTH,
2195 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2196 		.matches = has_address_auth_metacap,
2197 	},
2198 	{
2199 		.desc = "Generic authentication (architected algorithm)",
2200 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2201 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2202 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2203 		.sign = FTR_UNSIGNED,
2204 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2205 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2206 		.matches = has_cpuid_feature,
2207 	},
2208 	{
2209 		.desc = "Generic authentication (IMP DEF algorithm)",
2210 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2211 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2212 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2213 		.sign = FTR_UNSIGNED,
2214 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2215 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2216 		.matches = has_cpuid_feature,
2217 	},
2218 	{
2219 		.capability = ARM64_HAS_GENERIC_AUTH,
2220 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2221 		.matches = has_generic_auth,
2222 	},
2223 #endif /* CONFIG_ARM64_PTR_AUTH */
2224 #ifdef CONFIG_ARM64_PSEUDO_NMI
2225 	{
2226 		/*
2227 		 * Depends on having GICv3
2228 		 */
2229 		.desc = "IRQ priority masking",
2230 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2231 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2232 		.matches = can_use_gic_priorities,
2233 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2234 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2235 		.sign = FTR_UNSIGNED,
2236 		.min_field_value = 1,
2237 	},
2238 #endif
2239 #ifdef CONFIG_ARM64_E0PD
2240 	{
2241 		.desc = "E0PD",
2242 		.capability = ARM64_HAS_E0PD,
2243 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2244 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2245 		.sign = FTR_UNSIGNED,
2246 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2247 		.matches = has_cpuid_feature,
2248 		.min_field_value = 1,
2249 		.cpu_enable = cpu_enable_e0pd,
2250 	},
2251 #endif
2252 #ifdef CONFIG_ARCH_RANDOM
2253 	{
2254 		.desc = "Random Number Generator",
2255 		.capability = ARM64_HAS_RNG,
2256 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2257 		.matches = has_cpuid_feature,
2258 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2259 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2260 		.sign = FTR_UNSIGNED,
2261 		.min_field_value = 1,
2262 	},
2263 #endif
2264 #ifdef CONFIG_ARM64_BTI
2265 	{
2266 		.desc = "Branch Target Identification",
2267 		.capability = ARM64_BTI,
2268 #ifdef CONFIG_ARM64_BTI_KERNEL
2269 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2270 #else
2271 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2272 #endif
2273 		.matches = has_cpuid_feature,
2274 		.cpu_enable = bti_enable,
2275 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2276 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2277 		.min_field_value = ID_AA64PFR1_BT_BTI,
2278 		.sign = FTR_UNSIGNED,
2279 	},
2280 #endif
2281 #ifdef CONFIG_ARM64_MTE
2282 	{
2283 		.desc = "Memory Tagging Extension",
2284 		.capability = ARM64_MTE,
2285 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2286 		.matches = has_cpuid_feature,
2287 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2288 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2289 		.min_field_value = ID_AA64PFR1_MTE,
2290 		.sign = FTR_UNSIGNED,
2291 		.cpu_enable = cpu_enable_mte,
2292 	},
2293 #endif /* CONFIG_ARM64_MTE */
2294 	{
2295 		.desc = "RCpc load-acquire (LDAPR)",
2296 		.capability = ARM64_HAS_LDAPR,
2297 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2298 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2299 		.sign = FTR_UNSIGNED,
2300 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2301 		.matches = has_cpuid_feature,
2302 		.min_field_value = 1,
2303 	},
2304 	{},
2305 };
2306 
2307 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2308 		.matches = has_cpuid_feature,					\
2309 		.sys_reg = reg,							\
2310 		.field_pos = field,						\
2311 		.sign = s,							\
2312 		.min_field_value = min_value,
2313 
2314 #define __HWCAP_CAP(name, cap_type, cap)					\
2315 		.desc = name,							\
2316 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2317 		.hwcap_type = cap_type,						\
2318 		.hwcap = cap,							\
2319 
2320 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2321 	{									\
2322 		__HWCAP_CAP(#cap, cap_type, cap)				\
2323 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2324 	}
2325 
2326 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2327 	{									\
2328 		__HWCAP_CAP(#cap, cap_type, cap)				\
2329 		.matches = cpucap_multi_entry_cap_matches,			\
2330 		.match_list = list,						\
2331 	}
2332 
2333 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2334 	{									\
2335 		__HWCAP_CAP(#cap, cap_type, cap)				\
2336 		.matches = match,						\
2337 	}
2338 
2339 #ifdef CONFIG_ARM64_PTR_AUTH
2340 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2341 	{
2342 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2343 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2344 	},
2345 	{
2346 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2347 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2348 	},
2349 	{},
2350 };
2351 
2352 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2353 	{
2354 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2355 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2356 	},
2357 	{
2358 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2359 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2360 	},
2361 	{},
2362 };
2363 #endif
2364 
2365 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2366 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2367 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2368 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2369 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2370 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2371 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2372 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2373 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2374 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2375 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2376 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2377 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2378 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2379 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2380 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2381 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2382 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2383 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2384 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2385 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2386 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2387 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2388 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2389 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2390 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2391 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2392 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2393 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2394 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2395 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2396 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2397 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2398 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2399 #ifdef CONFIG_ARM64_SVE
2400 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2401 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2402 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2403 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2404 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2405 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2406 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2407 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2408 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2409 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2410 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2411 #endif
2412 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2413 #ifdef CONFIG_ARM64_BTI
2414 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2415 #endif
2416 #ifdef CONFIG_ARM64_PTR_AUTH
2417 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2418 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2419 #endif
2420 #ifdef CONFIG_ARM64_MTE
2421 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2422 #endif /* CONFIG_ARM64_MTE */
2423 	{},
2424 };
2425 
2426 #ifdef CONFIG_COMPAT
2427 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2428 {
2429 	/*
2430 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2431 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2432 	 * check is future proof, by making sure value is non-zero.
2433 	 */
2434 	u32 mvfr1;
2435 
2436 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2437 	if (scope == SCOPE_SYSTEM)
2438 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2439 	else
2440 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2441 
2442 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2443 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2444 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2445 }
2446 #endif
2447 
2448 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2449 #ifdef CONFIG_COMPAT
2450 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2451 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2452 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2453 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2454 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2455 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2456 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2457 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2458 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2459 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2460 #endif
2461 	{},
2462 };
2463 
2464 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2465 {
2466 	switch (cap->hwcap_type) {
2467 	case CAP_HWCAP:
2468 		cpu_set_feature(cap->hwcap);
2469 		break;
2470 #ifdef CONFIG_COMPAT
2471 	case CAP_COMPAT_HWCAP:
2472 		compat_elf_hwcap |= (u32)cap->hwcap;
2473 		break;
2474 	case CAP_COMPAT_HWCAP2:
2475 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2476 		break;
2477 #endif
2478 	default:
2479 		WARN_ON(1);
2480 		break;
2481 	}
2482 }
2483 
2484 /* Check if we have a particular HWCAP enabled */
2485 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2486 {
2487 	bool rc;
2488 
2489 	switch (cap->hwcap_type) {
2490 	case CAP_HWCAP:
2491 		rc = cpu_have_feature(cap->hwcap);
2492 		break;
2493 #ifdef CONFIG_COMPAT
2494 	case CAP_COMPAT_HWCAP:
2495 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2496 		break;
2497 	case CAP_COMPAT_HWCAP2:
2498 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2499 		break;
2500 #endif
2501 	default:
2502 		WARN_ON(1);
2503 		rc = false;
2504 	}
2505 
2506 	return rc;
2507 }
2508 
2509 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2510 {
2511 	/* We support emulation of accesses to CPU ID feature registers */
2512 	cpu_set_named_feature(CPUID);
2513 	for (; hwcaps->matches; hwcaps++)
2514 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2515 			cap_set_elf_hwcap(hwcaps);
2516 }
2517 
2518 static void update_cpu_capabilities(u16 scope_mask)
2519 {
2520 	int i;
2521 	const struct arm64_cpu_capabilities *caps;
2522 
2523 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2524 	for (i = 0; i < ARM64_NCAPS; i++) {
2525 		caps = cpu_hwcaps_ptrs[i];
2526 		if (!caps || !(caps->type & scope_mask) ||
2527 		    cpus_have_cap(caps->capability) ||
2528 		    !caps->matches(caps, cpucap_default_scope(caps)))
2529 			continue;
2530 
2531 		if (caps->desc)
2532 			pr_info("detected: %s\n", caps->desc);
2533 		cpus_set_cap(caps->capability);
2534 
2535 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2536 			set_bit(caps->capability, boot_capabilities);
2537 	}
2538 }
2539 
2540 /*
2541  * Enable all the available capabilities on this CPU. The capabilities
2542  * with BOOT_CPU scope are handled separately and hence skipped here.
2543  */
2544 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2545 {
2546 	int i;
2547 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2548 
2549 	for_each_available_cap(i) {
2550 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2551 
2552 		if (WARN_ON(!cap))
2553 			continue;
2554 
2555 		if (!(cap->type & non_boot_scope))
2556 			continue;
2557 
2558 		if (cap->cpu_enable)
2559 			cap->cpu_enable(cap);
2560 	}
2561 	return 0;
2562 }
2563 
2564 /*
2565  * Run through the enabled capabilities and enable() it on all active
2566  * CPUs
2567  */
2568 static void __init enable_cpu_capabilities(u16 scope_mask)
2569 {
2570 	int i;
2571 	const struct arm64_cpu_capabilities *caps;
2572 	bool boot_scope;
2573 
2574 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2575 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2576 
2577 	for (i = 0; i < ARM64_NCAPS; i++) {
2578 		unsigned int num;
2579 
2580 		caps = cpu_hwcaps_ptrs[i];
2581 		if (!caps || !(caps->type & scope_mask))
2582 			continue;
2583 		num = caps->capability;
2584 		if (!cpus_have_cap(num))
2585 			continue;
2586 
2587 		/* Ensure cpus_have_const_cap(num) works */
2588 		static_branch_enable(&cpu_hwcap_keys[num]);
2589 
2590 		if (boot_scope && caps->cpu_enable)
2591 			/*
2592 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2593 			 * before any secondary CPU boots. Thus, each secondary
2594 			 * will enable the capability as appropriate via
2595 			 * check_local_cpu_capabilities(). The only exception is
2596 			 * the boot CPU, for which the capability must be
2597 			 * enabled here. This approach avoids costly
2598 			 * stop_machine() calls for this case.
2599 			 */
2600 			caps->cpu_enable(caps);
2601 	}
2602 
2603 	/*
2604 	 * For all non-boot scope capabilities, use stop_machine()
2605 	 * as it schedules the work allowing us to modify PSTATE,
2606 	 * instead of on_each_cpu() which uses an IPI, giving us a
2607 	 * PSTATE that disappears when we return.
2608 	 */
2609 	if (!boot_scope)
2610 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2611 			     NULL, cpu_online_mask);
2612 }
2613 
2614 /*
2615  * Run through the list of capabilities to check for conflicts.
2616  * If the system has already detected a capability, take necessary
2617  * action on this CPU.
2618  */
2619 static void verify_local_cpu_caps(u16 scope_mask)
2620 {
2621 	int i;
2622 	bool cpu_has_cap, system_has_cap;
2623 	const struct arm64_cpu_capabilities *caps;
2624 
2625 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2626 
2627 	for (i = 0; i < ARM64_NCAPS; i++) {
2628 		caps = cpu_hwcaps_ptrs[i];
2629 		if (!caps || !(caps->type & scope_mask))
2630 			continue;
2631 
2632 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2633 		system_has_cap = cpus_have_cap(caps->capability);
2634 
2635 		if (system_has_cap) {
2636 			/*
2637 			 * Check if the new CPU misses an advertised feature,
2638 			 * which is not safe to miss.
2639 			 */
2640 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2641 				break;
2642 			/*
2643 			 * We have to issue cpu_enable() irrespective of
2644 			 * whether the CPU has it or not, as it is enabeld
2645 			 * system wide. It is upto the call back to take
2646 			 * appropriate action on this CPU.
2647 			 */
2648 			if (caps->cpu_enable)
2649 				caps->cpu_enable(caps);
2650 		} else {
2651 			/*
2652 			 * Check if the CPU has this capability if it isn't
2653 			 * safe to have when the system doesn't.
2654 			 */
2655 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2656 				break;
2657 		}
2658 	}
2659 
2660 	if (i < ARM64_NCAPS) {
2661 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2662 			smp_processor_id(), caps->capability,
2663 			caps->desc, system_has_cap, cpu_has_cap);
2664 
2665 		if (cpucap_panic_on_conflict(caps))
2666 			cpu_panic_kernel();
2667 		else
2668 			cpu_die_early();
2669 	}
2670 }
2671 
2672 /*
2673  * Check for CPU features that are used in early boot
2674  * based on the Boot CPU value.
2675  */
2676 static void check_early_cpu_features(void)
2677 {
2678 	verify_cpu_asid_bits();
2679 
2680 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2681 }
2682 
2683 static void
2684 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2685 {
2686 
2687 	for (; caps->matches; caps++)
2688 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2689 			pr_crit("CPU%d: missing HWCAP: %s\n",
2690 					smp_processor_id(), caps->desc);
2691 			cpu_die_early();
2692 		}
2693 }
2694 
2695 static void verify_local_elf_hwcaps(void)
2696 {
2697 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2698 
2699 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2700 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2701 }
2702 
2703 static void verify_sve_features(void)
2704 {
2705 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2706 	u64 zcr = read_zcr_features();
2707 
2708 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2709 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2710 
2711 	if (len < safe_len || sve_verify_vq_map()) {
2712 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2713 			smp_processor_id());
2714 		cpu_die_early();
2715 	}
2716 
2717 	/* Add checks on other ZCR bits here if necessary */
2718 }
2719 
2720 static void verify_hyp_capabilities(void)
2721 {
2722 	u64 safe_mmfr1, mmfr0, mmfr1;
2723 	int parange, ipa_max;
2724 	unsigned int safe_vmid_bits, vmid_bits;
2725 
2726 	if (!IS_ENABLED(CONFIG_KVM))
2727 		return;
2728 
2729 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2730 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2731 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2732 
2733 	/* Verify VMID bits */
2734 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2735 	vmid_bits = get_vmid_bits(mmfr1);
2736 	if (vmid_bits < safe_vmid_bits) {
2737 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2738 		cpu_die_early();
2739 	}
2740 
2741 	/* Verify IPA range */
2742 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2743 				ID_AA64MMFR0_PARANGE_SHIFT);
2744 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2745 	if (ipa_max < get_kvm_ipa_limit()) {
2746 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2747 		cpu_die_early();
2748 	}
2749 }
2750 
2751 /*
2752  * Run through the enabled system capabilities and enable() it on this CPU.
2753  * The capabilities were decided based on the available CPUs at the boot time.
2754  * Any new CPU should match the system wide status of the capability. If the
2755  * new CPU doesn't have a capability which the system now has enabled, we
2756  * cannot do anything to fix it up and could cause unexpected failures. So
2757  * we park the CPU.
2758  */
2759 static void verify_local_cpu_capabilities(void)
2760 {
2761 	/*
2762 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2763 	 * check_early_cpu_features(), as they need to be verified
2764 	 * on all secondary CPUs.
2765 	 */
2766 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2767 	verify_local_elf_hwcaps();
2768 
2769 	if (system_supports_sve())
2770 		verify_sve_features();
2771 
2772 	if (is_hyp_mode_available())
2773 		verify_hyp_capabilities();
2774 }
2775 
2776 void check_local_cpu_capabilities(void)
2777 {
2778 	/*
2779 	 * All secondary CPUs should conform to the early CPU features
2780 	 * in use by the kernel based on boot CPU.
2781 	 */
2782 	check_early_cpu_features();
2783 
2784 	/*
2785 	 * If we haven't finalised the system capabilities, this CPU gets
2786 	 * a chance to update the errata work arounds and local features.
2787 	 * Otherwise, this CPU should verify that it has all the system
2788 	 * advertised capabilities.
2789 	 */
2790 	if (!system_capabilities_finalized())
2791 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2792 	else
2793 		verify_local_cpu_capabilities();
2794 }
2795 
2796 static void __init setup_boot_cpu_capabilities(void)
2797 {
2798 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2799 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2800 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2801 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2802 }
2803 
2804 bool this_cpu_has_cap(unsigned int n)
2805 {
2806 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2807 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2808 
2809 		if (cap)
2810 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2811 	}
2812 
2813 	return false;
2814 }
2815 
2816 /*
2817  * This helper function is used in a narrow window when,
2818  * - The system wide safe registers are set with all the SMP CPUs and,
2819  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2820  * In all other cases cpus_have_{const_}cap() should be used.
2821  */
2822 static bool __maybe_unused __system_matches_cap(unsigned int n)
2823 {
2824 	if (n < ARM64_NCAPS) {
2825 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2826 
2827 		if (cap)
2828 			return cap->matches(cap, SCOPE_SYSTEM);
2829 	}
2830 	return false;
2831 }
2832 
2833 void cpu_set_feature(unsigned int num)
2834 {
2835 	WARN_ON(num >= MAX_CPU_FEATURES);
2836 	elf_hwcap |= BIT(num);
2837 }
2838 EXPORT_SYMBOL_GPL(cpu_set_feature);
2839 
2840 bool cpu_have_feature(unsigned int num)
2841 {
2842 	WARN_ON(num >= MAX_CPU_FEATURES);
2843 	return elf_hwcap & BIT(num);
2844 }
2845 EXPORT_SYMBOL_GPL(cpu_have_feature);
2846 
2847 unsigned long cpu_get_elf_hwcap(void)
2848 {
2849 	/*
2850 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2851 	 * note that for userspace compatibility we guarantee that bits 62
2852 	 * and 63 will always be returned as 0.
2853 	 */
2854 	return lower_32_bits(elf_hwcap);
2855 }
2856 
2857 unsigned long cpu_get_elf_hwcap2(void)
2858 {
2859 	return upper_32_bits(elf_hwcap);
2860 }
2861 
2862 static void __init setup_system_capabilities(void)
2863 {
2864 	/*
2865 	 * We have finalised the system-wide safe feature
2866 	 * registers, finalise the capabilities that depend
2867 	 * on it. Also enable all the available capabilities,
2868 	 * that are not enabled already.
2869 	 */
2870 	update_cpu_capabilities(SCOPE_SYSTEM);
2871 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2872 }
2873 
2874 void __init setup_cpu_features(void)
2875 {
2876 	u32 cwg;
2877 
2878 	setup_system_capabilities();
2879 	setup_elf_hwcaps(arm64_elf_hwcaps);
2880 
2881 	if (system_supports_32bit_el0())
2882 		setup_elf_hwcaps(compat_elf_hwcaps);
2883 
2884 	if (system_uses_ttbr0_pan())
2885 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2886 
2887 	sve_setup();
2888 	minsigstksz_setup();
2889 
2890 	/* Advertise that we have computed the system capabilities */
2891 	finalize_system_capabilities();
2892 
2893 	/*
2894 	 * Check for sane CTR_EL0.CWG value.
2895 	 */
2896 	cwg = cache_type_cwg();
2897 	if (!cwg)
2898 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2899 			ARCH_DMA_MINALIGN);
2900 }
2901 
2902 static int enable_mismatched_32bit_el0(unsigned int cpu)
2903 {
2904 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
2905 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
2906 
2907 	if (cpu_32bit) {
2908 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
2909 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
2910 		setup_elf_hwcaps(compat_elf_hwcaps);
2911 	}
2912 
2913 	return 0;
2914 }
2915 
2916 static int __init init_32bit_el0_mask(void)
2917 {
2918 	if (!allow_mismatched_32bit_el0)
2919 		return 0;
2920 
2921 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
2922 		return -ENOMEM;
2923 
2924 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
2925 				 "arm64/mismatched_32bit_el0:online",
2926 				 enable_mismatched_32bit_el0, NULL);
2927 }
2928 subsys_initcall_sync(init_32bit_el0_mask);
2929 
2930 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2931 {
2932 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2933 }
2934 
2935 /*
2936  * We emulate only the following system register space.
2937  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2938  * See Table C5-6 System instruction encodings for System register accesses,
2939  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2940  */
2941 static inline bool __attribute_const__ is_emulated(u32 id)
2942 {
2943 	return (sys_reg_Op0(id) == 0x3 &&
2944 		sys_reg_CRn(id) == 0x0 &&
2945 		sys_reg_Op1(id) == 0x0 &&
2946 		(sys_reg_CRm(id) == 0 ||
2947 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2948 }
2949 
2950 /*
2951  * With CRm == 0, reg should be one of :
2952  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2953  */
2954 static inline int emulate_id_reg(u32 id, u64 *valp)
2955 {
2956 	switch (id) {
2957 	case SYS_MIDR_EL1:
2958 		*valp = read_cpuid_id();
2959 		break;
2960 	case SYS_MPIDR_EL1:
2961 		*valp = SYS_MPIDR_SAFE_VAL;
2962 		break;
2963 	case SYS_REVIDR_EL1:
2964 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2965 		*valp = 0;
2966 		break;
2967 	default:
2968 		return -EINVAL;
2969 	}
2970 
2971 	return 0;
2972 }
2973 
2974 static int emulate_sys_reg(u32 id, u64 *valp)
2975 {
2976 	struct arm64_ftr_reg *regp;
2977 
2978 	if (!is_emulated(id))
2979 		return -EINVAL;
2980 
2981 	if (sys_reg_CRm(id) == 0)
2982 		return emulate_id_reg(id, valp);
2983 
2984 	regp = get_arm64_ftr_reg_nowarn(id);
2985 	if (regp)
2986 		*valp = arm64_ftr_reg_user_value(regp);
2987 	else
2988 		/*
2989 		 * The untracked registers are either IMPLEMENTATION DEFINED
2990 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2991 		 */
2992 		*valp = 0;
2993 	return 0;
2994 }
2995 
2996 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2997 {
2998 	int rc;
2999 	u64 val;
3000 
3001 	rc = emulate_sys_reg(sys_reg, &val);
3002 	if (!rc) {
3003 		pt_regs_write_reg(regs, rt, val);
3004 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3005 	}
3006 	return rc;
3007 }
3008 
3009 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3010 {
3011 	u32 sys_reg, rt;
3012 
3013 	/*
3014 	 * sys_reg values are defined as used in mrs/msr instruction.
3015 	 * shift the imm value to get the encoding.
3016 	 */
3017 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3018 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3019 	return do_emulate_mrs(regs, sys_reg, rt);
3020 }
3021 
3022 static struct undef_hook mrs_hook = {
3023 	.instr_mask = 0xffff0000,
3024 	.instr_val  = 0xd5380000,
3025 	.pstate_mask = PSR_AA32_MODE_MASK,
3026 	.pstate_val = PSR_MODE_EL0t,
3027 	.fn = emulate_mrs,
3028 };
3029 
3030 static int __init enable_mrs_emulation(void)
3031 {
3032 	register_undef_hook(&mrs_hook);
3033 	return 0;
3034 }
3035 
3036 core_initcall(enable_mrs_emulation);
3037 
3038 enum mitigation_state arm64_get_meltdown_state(void)
3039 {
3040 	if (__meltdown_safe)
3041 		return SPECTRE_UNAFFECTED;
3042 
3043 	if (arm64_kernel_unmapped_at_el0())
3044 		return SPECTRE_MITIGATED;
3045 
3046 	return SPECTRE_VULNERABLE;
3047 }
3048 
3049 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3050 			  char *buf)
3051 {
3052 	switch (arm64_get_meltdown_state()) {
3053 	case SPECTRE_UNAFFECTED:
3054 		return sprintf(buf, "Not affected\n");
3055 
3056 	case SPECTRE_MITIGATED:
3057 		return sprintf(buf, "Mitigation: PTI\n");
3058 
3059 	default:
3060 		return sprintf(buf, "Vulnerable\n");
3061 	}
3062 }
3063