xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision f5ad1c74)
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/mm.h>
72 #include <linux/cpu.h>
73 #include <asm/cpu.h>
74 #include <asm/cpufeature.h>
75 #include <asm/cpu_ops.h>
76 #include <asm/fpsimd.h>
77 #include <asm/mmu_context.h>
78 #include <asm/mte.h>
79 #include <asm/processor.h>
80 #include <asm/sysreg.h>
81 #include <asm/traps.h>
82 #include <asm/virt.h>
83 
84 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
85 static unsigned long elf_hwcap __read_mostly;
86 
87 #ifdef CONFIG_COMPAT
88 #define COMPAT_ELF_HWCAP_DEFAULT	\
89 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
90 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
91 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
92 				 COMPAT_HWCAP_LPAE)
93 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
94 unsigned int compat_elf_hwcap2 __read_mostly;
95 #endif
96 
97 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
98 EXPORT_SYMBOL(cpu_hwcaps);
99 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
100 
101 /* Need also bit for ARM64_CB_PATCH */
102 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
103 
104 bool arm64_use_ng_mappings = false;
105 EXPORT_SYMBOL(arm64_use_ng_mappings);
106 
107 /*
108  * Flag to indicate if we have computed the system wide
109  * capabilities based on the boot time active CPUs. This
110  * will be used to determine if a new booting CPU should
111  * go through the verification process to make sure that it
112  * supports the system capabilities, without using a hotplug
113  * notifier. This is also used to decide if we could use
114  * the fast path for checking constant CPU caps.
115  */
116 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
117 EXPORT_SYMBOL(arm64_const_caps_ready);
118 static inline void finalize_system_capabilities(void)
119 {
120 	static_branch_enable(&arm64_const_caps_ready);
121 }
122 
123 void dump_cpu_features(void)
124 {
125 	/* file-wide pr_fmt adds "CPU features: " prefix */
126 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
127 }
128 
129 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
130 EXPORT_SYMBOL(cpu_hwcap_keys);
131 
132 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
133 	{						\
134 		.sign = SIGNED,				\
135 		.visible = VISIBLE,			\
136 		.strict = STRICT,			\
137 		.type = TYPE,				\
138 		.shift = SHIFT,				\
139 		.width = WIDTH,				\
140 		.safe_val = SAFE_VAL,			\
141 	}
142 
143 /* Define a feature with unsigned values */
144 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
145 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
146 
147 /* Define a feature with a signed value */
148 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
149 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
150 
151 #define ARM64_FTR_END					\
152 	{						\
153 		.width = 0,				\
154 	}
155 
156 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
157 
158 static bool __system_matches_cap(unsigned int n);
159 
160 /*
161  * NOTE: Any changes to the visibility of features should be kept in
162  * sync with the documentation of the CPU feature register ABI.
163  */
164 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
165 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
166 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
167 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
168 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
169 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
170 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
171 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
172 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
173 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
174 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
175 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
176 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
178 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
179 	ARM64_FTR_END,
180 };
181 
182 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
183 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
184 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
187 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
188 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
189 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
190 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
192 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
197 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
199 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
201 	ARM64_FTR_END,
202 };
203 
204 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
205 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
212 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
214 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
215 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
216 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
217 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
220 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
221 	ARM64_FTR_END,
222 };
223 
224 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
225 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
228 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
229 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
230 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
231 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
232 	ARM64_FTR_END,
233 };
234 
235 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
236 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
237 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
238 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
239 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
241 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
243 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
244 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
245 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
246 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
247 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
249 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
251 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
252 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
253 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
254 	ARM64_FTR_END,
255 };
256 
257 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
258 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
259 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
260 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
261 	/*
262 	 * Page size not being supported at Stage-2 is not fatal. You
263 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
264 	 * your favourite nesting hypervisor.
265 	 *
266 	 * There is a small corner case where the hypervisor explicitly
267 	 * advertises a given granule size at Stage-2 (value 2) on some
268 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
269 	 * vCPUs. Although this is not forbidden by the architecture, it
270 	 * indicates that the hypervisor is being silly (or buggy).
271 	 *
272 	 * We make no effort to cope with this and pretend that if these
273 	 * fields are inconsistent across vCPUs, then it isn't worth
274 	 * trying to bring KVM up.
275 	 */
276 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
277 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
278 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
279 	/*
280 	 * We already refuse to boot CPUs that don't support our configured
281 	 * page size, so we can only detect mismatches for a page size other
282 	 * than the one we're currently using. Unfortunately, SoCs like this
283 	 * exist in the wild so, even though we don't like it, we'll have to go
284 	 * along with it and treat them as non-strict.
285 	 */
286 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
287 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
288 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
289 
290 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
291 	/* Linux shouldn't care about secure memory */
292 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
293 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
294 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
295 	/*
296 	 * Differing PARange is fine as long as all peripherals and memory are mapped
297 	 * within the minimum PARange of all CPUs
298 	 */
299 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
300 	ARM64_FTR_END,
301 };
302 
303 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
304 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
305 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
306 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
307 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
308 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
309 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
310 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
311 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
312 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
313 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
314 	ARM64_FTR_END,
315 };
316 
317 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
318 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
319 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
320 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
324 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
326 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
330 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
331 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
332 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
333 	ARM64_FTR_END,
334 };
335 
336 static const struct arm64_ftr_bits ftr_ctr[] = {
337 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
338 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
339 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
340 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
343 	/*
344 	 * Linux can handle differing I-cache policies. Userspace JITs will
345 	 * make use of *minLine.
346 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
347 	 */
348 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
349 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
350 	ARM64_FTR_END,
351 };
352 
353 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
354 	.name		= "SYS_CTR_EL0",
355 	.ftr_bits	= ftr_ctr
356 };
357 
358 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
359 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
360 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
361 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
362 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
363 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
364 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
365 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
367 	ARM64_FTR_END,
368 };
369 
370 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
371 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
372 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
373 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
374 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
375 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
376 	/*
377 	 * We can instantiate multiple PMU instances with different levels
378 	 * of support.
379 	 */
380 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
381 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0),
382 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
383 	ARM64_FTR_END,
384 };
385 
386 static const struct arm64_ftr_bits ftr_mvfr2[] = {
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
389 	ARM64_FTR_END,
390 };
391 
392 static const struct arm64_ftr_bits ftr_dczid[] = {
393 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
394 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
395 	ARM64_FTR_END,
396 };
397 
398 static const struct arm64_ftr_bits ftr_id_isar0[] = {
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
402 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
403 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
404 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
405 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
406 	ARM64_FTR_END,
407 };
408 
409 static const struct arm64_ftr_bits ftr_id_isar5[] = {
410 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
411 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
412 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
415 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
416 	ARM64_FTR_END,
417 };
418 
419 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
420 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
421 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
422 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
423 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
424 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
425 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
427 
428 	/*
429 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
430 	 * external abort on speculative read. It is safe to assume that an
431 	 * SError might be generated than it will not be. Hence it has been
432 	 * classified as FTR_HIGHER_SAFE.
433 	 */
434 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
435 	ARM64_FTR_END,
436 };
437 
438 static const struct arm64_ftr_bits ftr_id_isar4[] = {
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
444 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
446 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
447 	ARM64_FTR_END,
448 };
449 
450 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
452 	ARM64_FTR_END,
453 };
454 
455 static const struct arm64_ftr_bits ftr_id_isar6[] = {
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
459 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
460 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
461 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
462 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
463 	ARM64_FTR_END,
464 };
465 
466 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
467 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
468 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
473 	ARM64_FTR_END,
474 };
475 
476 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
478 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
479 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
480 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
484 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
485 	ARM64_FTR_END,
486 };
487 
488 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
489 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
490 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
491 	ARM64_FTR_END,
492 };
493 
494 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
495 	/* [31:28] TraceFilt */
496 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
501 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
503 	ARM64_FTR_END,
504 };
505 
506 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
507 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
508 	ARM64_FTR_END,
509 };
510 
511 static const struct arm64_ftr_bits ftr_zcr[] = {
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
513 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
514 	ARM64_FTR_END,
515 };
516 
517 /*
518  * Common ftr bits for a 32bit register with all hidden, strict
519  * attributes, with 4bit feature fields and a default safe value of
520  * 0. Covers the following 32bit registers:
521  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
522  */
523 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
524 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
525 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
526 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
527 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
531 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
532 	ARM64_FTR_END,
533 };
534 
535 /* Table for a single 32bit feature value */
536 static const struct arm64_ftr_bits ftr_single32[] = {
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
538 	ARM64_FTR_END,
539 };
540 
541 static const struct arm64_ftr_bits ftr_raz[] = {
542 	ARM64_FTR_END,
543 };
544 
545 #define ARM64_FTR_REG(id, table) {		\
546 	.sys_id = id,				\
547 	.reg = 	&(struct arm64_ftr_reg){	\
548 		.name = #id,			\
549 		.ftr_bits = &((table)[0]),	\
550 	}}
551 
552 static const struct __ftr_reg_entry {
553 	u32			sys_id;
554 	struct arm64_ftr_reg 	*reg;
555 } arm64_ftr_regs[] = {
556 
557 	/* Op1 = 0, CRn = 0, CRm = 1 */
558 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
559 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
560 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
561 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
562 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
563 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
564 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
565 
566 	/* Op1 = 0, CRn = 0, CRm = 2 */
567 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
568 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
569 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
570 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
571 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
572 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
573 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
574 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
575 
576 	/* Op1 = 0, CRn = 0, CRm = 3 */
577 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
578 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
579 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
580 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
581 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
582 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
583 
584 	/* Op1 = 0, CRn = 0, CRm = 4 */
585 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
586 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
587 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
588 
589 	/* Op1 = 0, CRn = 0, CRm = 5 */
590 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
591 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
592 
593 	/* Op1 = 0, CRn = 0, CRm = 6 */
594 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
595 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
596 
597 	/* Op1 = 0, CRn = 0, CRm = 7 */
598 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
599 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
600 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
601 
602 	/* Op1 = 0, CRn = 1, CRm = 2 */
603 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
604 
605 	/* Op1 = 3, CRn = 0, CRm = 0 */
606 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
607 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
608 
609 	/* Op1 = 3, CRn = 14, CRm = 0 */
610 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
611 };
612 
613 static int search_cmp_ftr_reg(const void *id, const void *regp)
614 {
615 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
616 }
617 
618 /*
619  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
620  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
621  * ascending order of sys_id, we use binary search to find a matching
622  * entry.
623  *
624  * returns - Upon success,  matching ftr_reg entry for id.
625  *         - NULL on failure. It is upto the caller to decide
626  *	     the impact of a failure.
627  */
628 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
629 {
630 	const struct __ftr_reg_entry *ret;
631 
632 	ret = bsearch((const void *)(unsigned long)sys_id,
633 			arm64_ftr_regs,
634 			ARRAY_SIZE(arm64_ftr_regs),
635 			sizeof(arm64_ftr_regs[0]),
636 			search_cmp_ftr_reg);
637 	if (ret)
638 		return ret->reg;
639 	return NULL;
640 }
641 
642 /*
643  * get_arm64_ftr_reg - Looks up a feature register entry using
644  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
645  *
646  * returns - Upon success,  matching ftr_reg entry for id.
647  *         - NULL on failure but with an WARN_ON().
648  */
649 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
650 {
651 	struct arm64_ftr_reg *reg;
652 
653 	reg = get_arm64_ftr_reg_nowarn(sys_id);
654 
655 	/*
656 	 * Requesting a non-existent register search is an error. Warn
657 	 * and let the caller handle it.
658 	 */
659 	WARN_ON(!reg);
660 	return reg;
661 }
662 
663 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
664 			       s64 ftr_val)
665 {
666 	u64 mask = arm64_ftr_mask(ftrp);
667 
668 	reg &= ~mask;
669 	reg |= (ftr_val << ftrp->shift) & mask;
670 	return reg;
671 }
672 
673 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
674 				s64 cur)
675 {
676 	s64 ret = 0;
677 
678 	switch (ftrp->type) {
679 	case FTR_EXACT:
680 		ret = ftrp->safe_val;
681 		break;
682 	case FTR_LOWER_SAFE:
683 		ret = new < cur ? new : cur;
684 		break;
685 	case FTR_HIGHER_OR_ZERO_SAFE:
686 		if (!cur || !new)
687 			break;
688 		fallthrough;
689 	case FTR_HIGHER_SAFE:
690 		ret = new > cur ? new : cur;
691 		break;
692 	default:
693 		BUG();
694 	}
695 
696 	return ret;
697 }
698 
699 static void __init sort_ftr_regs(void)
700 {
701 	unsigned int i;
702 
703 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
704 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
705 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
706 		unsigned int j = 0;
707 
708 		/*
709 		 * Features here must be sorted in descending order with respect
710 		 * to their shift values and should not overlap with each other.
711 		 */
712 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
713 			unsigned int width = ftr_reg->ftr_bits[j].width;
714 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
715 			unsigned int prev_shift;
716 
717 			WARN((shift  + width) > 64,
718 				"%s has invalid feature at shift %d\n",
719 				ftr_reg->name, shift);
720 
721 			/*
722 			 * Skip the first feature. There is nothing to
723 			 * compare against for now.
724 			 */
725 			if (j == 0)
726 				continue;
727 
728 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
729 			WARN((shift + width) > prev_shift,
730 				"%s has feature overlap at shift %d\n",
731 				ftr_reg->name, shift);
732 		}
733 
734 		/*
735 		 * Skip the first register. There is nothing to
736 		 * compare against for now.
737 		 */
738 		if (i == 0)
739 			continue;
740 		/*
741 		 * Registers here must be sorted in ascending order with respect
742 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
743 		 * to work correctly.
744 		 */
745 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
746 	}
747 }
748 
749 /*
750  * Initialise the CPU feature register from Boot CPU values.
751  * Also initiliases the strict_mask for the register.
752  * Any bits that are not covered by an arm64_ftr_bits entry are considered
753  * RES0 for the system-wide value, and must strictly match.
754  */
755 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
756 {
757 	u64 val = 0;
758 	u64 strict_mask = ~0x0ULL;
759 	u64 user_mask = 0;
760 	u64 valid_mask = 0;
761 
762 	const struct arm64_ftr_bits *ftrp;
763 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
764 
765 	if (!reg)
766 		return;
767 
768 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
769 		u64 ftr_mask = arm64_ftr_mask(ftrp);
770 		s64 ftr_new = arm64_ftr_value(ftrp, new);
771 
772 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
773 
774 		valid_mask |= ftr_mask;
775 		if (!ftrp->strict)
776 			strict_mask &= ~ftr_mask;
777 		if (ftrp->visible)
778 			user_mask |= ftr_mask;
779 		else
780 			reg->user_val = arm64_ftr_set_value(ftrp,
781 							    reg->user_val,
782 							    ftrp->safe_val);
783 	}
784 
785 	val &= valid_mask;
786 
787 	reg->sys_val = val;
788 	reg->strict_mask = strict_mask;
789 	reg->user_mask = user_mask;
790 }
791 
792 extern const struct arm64_cpu_capabilities arm64_errata[];
793 static const struct arm64_cpu_capabilities arm64_features[];
794 
795 static void __init
796 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
797 {
798 	for (; caps->matches; caps++) {
799 		if (WARN(caps->capability >= ARM64_NCAPS,
800 			"Invalid capability %d\n", caps->capability))
801 			continue;
802 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
803 			"Duplicate entry for capability %d\n",
804 			caps->capability))
805 			continue;
806 		cpu_hwcaps_ptrs[caps->capability] = caps;
807 	}
808 }
809 
810 static void __init init_cpu_hwcaps_indirect_list(void)
811 {
812 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
813 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
814 }
815 
816 static void __init setup_boot_cpu_capabilities(void);
817 
818 void __init init_cpu_features(struct cpuinfo_arm64 *info)
819 {
820 	/* Before we start using the tables, make sure it is sorted */
821 	sort_ftr_regs();
822 
823 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
824 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
825 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
826 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
827 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
828 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
829 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
830 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
831 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
832 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
833 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
834 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
835 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
836 
837 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
838 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
839 		init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
840 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
841 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
842 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
843 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
844 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
845 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
846 		init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
847 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
848 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
849 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
850 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
851 		init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
852 		init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
853 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
854 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
855 		init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
856 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
857 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
858 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
859 	}
860 
861 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
862 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
863 		sve_init_vq_map();
864 	}
865 
866 	/*
867 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
868 	 * before we handle the boot CPU below.
869 	 */
870 	init_cpu_hwcaps_indirect_list();
871 
872 	/*
873 	 * Detect and enable early CPU capabilities based on the boot CPU,
874 	 * after we have initialised the CPU feature infrastructure.
875 	 */
876 	setup_boot_cpu_capabilities();
877 }
878 
879 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
880 {
881 	const struct arm64_ftr_bits *ftrp;
882 
883 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
884 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
885 		s64 ftr_new = arm64_ftr_value(ftrp, new);
886 
887 		if (ftr_cur == ftr_new)
888 			continue;
889 		/* Find a safe value */
890 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
891 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
892 	}
893 
894 }
895 
896 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
897 {
898 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
899 
900 	if (!regp)
901 		return 0;
902 
903 	update_cpu_ftr_reg(regp, val);
904 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
905 		return 0;
906 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
907 			regp->name, boot, cpu, val);
908 	return 1;
909 }
910 
911 static void relax_cpu_ftr_reg(u32 sys_id, int field)
912 {
913 	const struct arm64_ftr_bits *ftrp;
914 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
915 
916 	if (!regp)
917 		return;
918 
919 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
920 		if (ftrp->shift == field) {
921 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
922 			break;
923 		}
924 	}
925 
926 	/* Bogus field? */
927 	WARN_ON(!ftrp->width);
928 }
929 
930 static int update_32bit_cpu_features(int cpu, struct cpuinfo_arm64 *info,
931 				     struct cpuinfo_arm64 *boot)
932 {
933 	int taint = 0;
934 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
935 
936 	/*
937 	 * If we don't have AArch32 at all then skip the checks entirely
938 	 * as the register values may be UNKNOWN and we're not going to be
939 	 * using them for anything.
940 	 */
941 	if (!id_aa64pfr0_32bit_el0(pfr0))
942 		return taint;
943 
944 	/*
945 	 * If we don't have AArch32 at EL1, then relax the strictness of
946 	 * EL1-dependent register fields to avoid spurious sanity check fails.
947 	 */
948 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
949 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
950 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
951 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
952 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
953 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
954 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
955 	}
956 
957 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
958 				      info->reg_id_dfr0, boot->reg_id_dfr0);
959 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
960 				      info->reg_id_dfr1, boot->reg_id_dfr1);
961 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
962 				      info->reg_id_isar0, boot->reg_id_isar0);
963 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
964 				      info->reg_id_isar1, boot->reg_id_isar1);
965 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
966 				      info->reg_id_isar2, boot->reg_id_isar2);
967 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
968 				      info->reg_id_isar3, boot->reg_id_isar3);
969 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
970 				      info->reg_id_isar4, boot->reg_id_isar4);
971 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
972 				      info->reg_id_isar5, boot->reg_id_isar5);
973 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
974 				      info->reg_id_isar6, boot->reg_id_isar6);
975 
976 	/*
977 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
978 	 * ACTLR formats could differ across CPUs and therefore would have to
979 	 * be trapped for virtualization anyway.
980 	 */
981 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
982 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
983 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
984 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
985 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
986 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
987 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
988 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
989 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
990 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
991 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
992 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
993 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
994 				      info->reg_id_pfr0, boot->reg_id_pfr0);
995 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
996 				      info->reg_id_pfr1, boot->reg_id_pfr1);
997 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
998 				      info->reg_id_pfr2, boot->reg_id_pfr2);
999 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1000 				      info->reg_mvfr0, boot->reg_mvfr0);
1001 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1002 				      info->reg_mvfr1, boot->reg_mvfr1);
1003 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1004 				      info->reg_mvfr2, boot->reg_mvfr2);
1005 
1006 	return taint;
1007 }
1008 
1009 /*
1010  * Update system wide CPU feature registers with the values from a
1011  * non-boot CPU. Also performs SANITY checks to make sure that there
1012  * aren't any insane variations from that of the boot CPU.
1013  */
1014 void update_cpu_features(int cpu,
1015 			 struct cpuinfo_arm64 *info,
1016 			 struct cpuinfo_arm64 *boot)
1017 {
1018 	int taint = 0;
1019 
1020 	/*
1021 	 * The kernel can handle differing I-cache policies, but otherwise
1022 	 * caches should look identical. Userspace JITs will make use of
1023 	 * *minLine.
1024 	 */
1025 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1026 				      info->reg_ctr, boot->reg_ctr);
1027 
1028 	/*
1029 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1030 	 * could result in too much or too little memory being zeroed if a
1031 	 * process is preempted and migrated between CPUs.
1032 	 */
1033 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1034 				      info->reg_dczid, boot->reg_dczid);
1035 
1036 	/* If different, timekeeping will be broken (especially with KVM) */
1037 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1038 				      info->reg_cntfrq, boot->reg_cntfrq);
1039 
1040 	/*
1041 	 * The kernel uses self-hosted debug features and expects CPUs to
1042 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1043 	 * and BRPs to be identical.
1044 	 * ID_AA64DFR1 is currently RES0.
1045 	 */
1046 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1047 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1048 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1049 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1050 	/*
1051 	 * Even in big.LITTLE, processors should be identical instruction-set
1052 	 * wise.
1053 	 */
1054 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1055 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1056 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1057 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1058 
1059 	/*
1060 	 * Differing PARange support is fine as long as all peripherals and
1061 	 * memory are mapped within the minimum PARange of all CPUs.
1062 	 * Linux should not care about secure memory.
1063 	 */
1064 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1065 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1066 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1067 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1068 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1069 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1070 
1071 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1072 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1073 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1074 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1075 
1076 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1077 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1078 
1079 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1080 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1081 					info->reg_zcr, boot->reg_zcr);
1082 
1083 		/* Probe vector lengths, unless we already gave up on SVE */
1084 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1085 		    !system_capabilities_finalized())
1086 			sve_update_vq_map();
1087 	}
1088 
1089 	/*
1090 	 * This relies on a sanitised view of the AArch64 ID registers
1091 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1092 	 */
1093 	taint |= update_32bit_cpu_features(cpu, info, boot);
1094 
1095 	/*
1096 	 * Mismatched CPU features are a recipe for disaster. Don't even
1097 	 * pretend to support them.
1098 	 */
1099 	if (taint) {
1100 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1101 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1102 	}
1103 }
1104 
1105 u64 read_sanitised_ftr_reg(u32 id)
1106 {
1107 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1108 
1109 	if (!regp)
1110 		return 0;
1111 	return regp->sys_val;
1112 }
1113 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1114 
1115 #define read_sysreg_case(r)	\
1116 	case r:		return read_sysreg_s(r)
1117 
1118 /*
1119  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1120  * Read the system register on the current CPU
1121  */
1122 static u64 __read_sysreg_by_encoding(u32 sys_id)
1123 {
1124 	switch (sys_id) {
1125 	read_sysreg_case(SYS_ID_PFR0_EL1);
1126 	read_sysreg_case(SYS_ID_PFR1_EL1);
1127 	read_sysreg_case(SYS_ID_PFR2_EL1);
1128 	read_sysreg_case(SYS_ID_DFR0_EL1);
1129 	read_sysreg_case(SYS_ID_DFR1_EL1);
1130 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1131 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1132 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1133 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1134 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1135 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1136 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1137 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1138 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1139 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1140 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1141 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1142 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1143 	read_sysreg_case(SYS_MVFR0_EL1);
1144 	read_sysreg_case(SYS_MVFR1_EL1);
1145 	read_sysreg_case(SYS_MVFR2_EL1);
1146 
1147 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1148 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1149 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1150 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1151 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1152 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1153 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1154 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1155 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1156 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1157 
1158 	read_sysreg_case(SYS_CNTFRQ_EL0);
1159 	read_sysreg_case(SYS_CTR_EL0);
1160 	read_sysreg_case(SYS_DCZID_EL0);
1161 
1162 	default:
1163 		BUG();
1164 		return 0;
1165 	}
1166 }
1167 
1168 #include <linux/irqchip/arm-gic-v3.h>
1169 
1170 static bool
1171 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1172 {
1173 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1174 
1175 	return val >= entry->min_field_value;
1176 }
1177 
1178 static bool
1179 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1180 {
1181 	u64 val;
1182 
1183 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1184 	if (scope == SCOPE_SYSTEM)
1185 		val = read_sanitised_ftr_reg(entry->sys_reg);
1186 	else
1187 		val = __read_sysreg_by_encoding(entry->sys_reg);
1188 
1189 	return feature_matches(val, entry);
1190 }
1191 
1192 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1193 {
1194 	bool has_sre;
1195 
1196 	if (!has_cpuid_feature(entry, scope))
1197 		return false;
1198 
1199 	has_sre = gic_enable_sre();
1200 	if (!has_sre)
1201 		pr_warn_once("%s present but disabled by higher exception level\n",
1202 			     entry->desc);
1203 
1204 	return has_sre;
1205 }
1206 
1207 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1208 {
1209 	u32 midr = read_cpuid_id();
1210 
1211 	/* Cavium ThunderX pass 1.x and 2.x */
1212 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1213 		MIDR_CPU_VAR_REV(0, 0),
1214 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1215 }
1216 
1217 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1218 {
1219 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1220 
1221 	return cpuid_feature_extract_signed_field(pfr0,
1222 					ID_AA64PFR0_FP_SHIFT) < 0;
1223 }
1224 
1225 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1226 			  int scope)
1227 {
1228 	u64 ctr;
1229 
1230 	if (scope == SCOPE_SYSTEM)
1231 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1232 	else
1233 		ctr = read_cpuid_effective_cachetype();
1234 
1235 	return ctr & BIT(CTR_IDC_SHIFT);
1236 }
1237 
1238 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1239 {
1240 	/*
1241 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1242 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1243 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1244 	 * value.
1245 	 */
1246 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1247 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1248 }
1249 
1250 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1251 			  int scope)
1252 {
1253 	u64 ctr;
1254 
1255 	if (scope == SCOPE_SYSTEM)
1256 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1257 	else
1258 		ctr = read_cpuid_cachetype();
1259 
1260 	return ctr & BIT(CTR_DIC_SHIFT);
1261 }
1262 
1263 static bool __maybe_unused
1264 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1265 {
1266 	/*
1267 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1268 	 * may share TLB entries with a CPU stuck in the crashed
1269 	 * kernel.
1270 	 */
1271 	 if (is_kdump_kernel())
1272 		return false;
1273 
1274 	return has_cpuid_feature(entry, scope);
1275 }
1276 
1277 /*
1278  * This check is triggered during the early boot before the cpufeature
1279  * is initialised. Checking the status on the local CPU allows the boot
1280  * CPU to detect the need for non-global mappings and thus avoiding a
1281  * pagetable re-write after all the CPUs are booted. This check will be
1282  * anyway run on individual CPUs, allowing us to get the consistent
1283  * state once the SMP CPUs are up and thus make the switch to non-global
1284  * mappings if required.
1285  */
1286 bool kaslr_requires_kpti(void)
1287 {
1288 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1289 		return false;
1290 
1291 	/*
1292 	 * E0PD does a similar job to KPTI so can be used instead
1293 	 * where available.
1294 	 */
1295 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1296 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1297 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1298 						ID_AA64MMFR2_E0PD_SHIFT))
1299 			return false;
1300 	}
1301 
1302 	/*
1303 	 * Systems affected by Cavium erratum 24756 are incompatible
1304 	 * with KPTI.
1305 	 */
1306 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1307 		extern const struct midr_range cavium_erratum_27456_cpus[];
1308 
1309 		if (is_midr_in_range_list(read_cpuid_id(),
1310 					  cavium_erratum_27456_cpus))
1311 			return false;
1312 	}
1313 
1314 	return kaslr_offset() > 0;
1315 }
1316 
1317 static bool __meltdown_safe = true;
1318 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1319 
1320 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1321 				int scope)
1322 {
1323 	/* List of CPUs that are not vulnerable and don't need KPTI */
1324 	static const struct midr_range kpti_safe_list[] = {
1325 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1326 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1327 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1328 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1329 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1330 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1331 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1332 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1333 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1334 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1335 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1336 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1337 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1338 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1339 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1340 		{ /* sentinel */ }
1341 	};
1342 	char const *str = "kpti command line option";
1343 	bool meltdown_safe;
1344 
1345 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1346 
1347 	/* Defer to CPU feature registers */
1348 	if (has_cpuid_feature(entry, scope))
1349 		meltdown_safe = true;
1350 
1351 	if (!meltdown_safe)
1352 		__meltdown_safe = false;
1353 
1354 	/*
1355 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1356 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1357 	 * ends as well as you might imagine. Don't even try.
1358 	 */
1359 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1360 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1361 		__kpti_forced = -1;
1362 	}
1363 
1364 	/* Useful for KASLR robustness */
1365 	if (kaslr_requires_kpti()) {
1366 		if (!__kpti_forced) {
1367 			str = "KASLR";
1368 			__kpti_forced = 1;
1369 		}
1370 	}
1371 
1372 	if (cpu_mitigations_off() && !__kpti_forced) {
1373 		str = "mitigations=off";
1374 		__kpti_forced = -1;
1375 	}
1376 
1377 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1378 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1379 		return false;
1380 	}
1381 
1382 	/* Forced? */
1383 	if (__kpti_forced) {
1384 		pr_info_once("kernel page table isolation forced %s by %s\n",
1385 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1386 		return __kpti_forced > 0;
1387 	}
1388 
1389 	return !meltdown_safe;
1390 }
1391 
1392 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1393 static void
1394 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1395 {
1396 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1397 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1398 	kpti_remap_fn *remap_fn;
1399 
1400 	int cpu = smp_processor_id();
1401 
1402 	/*
1403 	 * We don't need to rewrite the page-tables if either we've done
1404 	 * it already or we have KASLR enabled and therefore have not
1405 	 * created any global mappings at all.
1406 	 */
1407 	if (arm64_use_ng_mappings)
1408 		return;
1409 
1410 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
1411 
1412 	cpu_install_idmap();
1413 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1414 	cpu_uninstall_idmap();
1415 
1416 	if (!cpu)
1417 		arm64_use_ng_mappings = true;
1418 
1419 	return;
1420 }
1421 #else
1422 static void
1423 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1424 {
1425 }
1426 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1427 
1428 static int __init parse_kpti(char *str)
1429 {
1430 	bool enabled;
1431 	int ret = strtobool(str, &enabled);
1432 
1433 	if (ret)
1434 		return ret;
1435 
1436 	__kpti_forced = enabled ? 1 : -1;
1437 	return 0;
1438 }
1439 early_param("kpti", parse_kpti);
1440 
1441 #ifdef CONFIG_ARM64_HW_AFDBM
1442 static inline void __cpu_enable_hw_dbm(void)
1443 {
1444 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1445 
1446 	write_sysreg(tcr, tcr_el1);
1447 	isb();
1448 	local_flush_tlb_all();
1449 }
1450 
1451 static bool cpu_has_broken_dbm(void)
1452 {
1453 	/* List of CPUs which have broken DBM support. */
1454 	static const struct midr_range cpus[] = {
1455 #ifdef CONFIG_ARM64_ERRATUM_1024718
1456 		MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0),  // A55 r0p0 -r1p0
1457 		/* Kryo4xx Silver (rdpe => r1p0) */
1458 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1459 #endif
1460 		{},
1461 	};
1462 
1463 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1464 }
1465 
1466 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1467 {
1468 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1469 	       !cpu_has_broken_dbm();
1470 }
1471 
1472 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1473 {
1474 	if (cpu_can_use_dbm(cap))
1475 		__cpu_enable_hw_dbm();
1476 }
1477 
1478 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1479 		       int __unused)
1480 {
1481 	static bool detected = false;
1482 	/*
1483 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1484 	 * run a mix of CPUs with and without the feature. So, we
1485 	 * unconditionally enable the capability to allow any late CPU
1486 	 * to use the feature. We only enable the control bits on the
1487 	 * CPU, if it actually supports.
1488 	 *
1489 	 * We have to make sure we print the "feature" detection only
1490 	 * when at least one CPU actually uses it. So check if this CPU
1491 	 * can actually use it and print the message exactly once.
1492 	 *
1493 	 * This is safe as all CPUs (including secondary CPUs - due to the
1494 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1495 	 * goes through the "matches" check exactly once. Also if a CPU
1496 	 * matches the criteria, it is guaranteed that the CPU will turn
1497 	 * the DBM on, as the capability is unconditionally enabled.
1498 	 */
1499 	if (!detected && cpu_can_use_dbm(cap)) {
1500 		detected = true;
1501 		pr_info("detected: Hardware dirty bit management\n");
1502 	}
1503 
1504 	return true;
1505 }
1506 
1507 #endif
1508 
1509 #ifdef CONFIG_ARM64_AMU_EXTN
1510 
1511 /*
1512  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1513  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1514  * information regarding all the events that it supports. When a CPU bit is
1515  * set in the cpumask, the user of this feature can only rely on the presence
1516  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1517  * counters are enabled or access to these counters is enabled by code
1518  * executed at higher exception levels (firmware).
1519  */
1520 static struct cpumask amu_cpus __read_mostly;
1521 
1522 bool cpu_has_amu_feat(int cpu)
1523 {
1524 	return cpumask_test_cpu(cpu, &amu_cpus);
1525 }
1526 
1527 int get_cpu_with_amu_feat(void)
1528 {
1529 	return cpumask_any(&amu_cpus);
1530 }
1531 
1532 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1533 {
1534 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1535 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1536 			smp_processor_id());
1537 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1538 		update_freq_counters_refs();
1539 	}
1540 }
1541 
1542 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1543 		    int __unused)
1544 {
1545 	/*
1546 	 * The AMU extension is a non-conflicting feature: the kernel can
1547 	 * safely run a mix of CPUs with and without support for the
1548 	 * activity monitors extension. Therefore, unconditionally enable
1549 	 * the capability to allow any late CPU to use the feature.
1550 	 *
1551 	 * With this feature unconditionally enabled, the cpu_enable
1552 	 * function will be called for all CPUs that match the criteria,
1553 	 * including secondary and hotplugged, marking this feature as
1554 	 * present on that respective CPU. The enable function will also
1555 	 * print a detection message.
1556 	 */
1557 
1558 	return true;
1559 }
1560 #else
1561 int get_cpu_with_amu_feat(void)
1562 {
1563 	return nr_cpu_ids;
1564 }
1565 #endif
1566 
1567 #ifdef CONFIG_ARM64_VHE
1568 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1569 {
1570 	return is_kernel_in_hyp_mode();
1571 }
1572 
1573 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1574 {
1575 	/*
1576 	 * Copy register values that aren't redirected by hardware.
1577 	 *
1578 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1579 	 * this value to tpidr_el2 before we patch the code. Once we've done
1580 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1581 	 * do anything here.
1582 	 */
1583 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1584 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1585 }
1586 #endif
1587 
1588 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1589 {
1590 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1591 
1592 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1593 	WARN_ON(val & (7 << 27 | 7 << 21));
1594 }
1595 
1596 #ifdef CONFIG_ARM64_PAN
1597 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1598 {
1599 	/*
1600 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1601 	 * is discarded once we return from the exception.
1602 	 */
1603 	WARN_ON_ONCE(in_interrupt());
1604 
1605 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1606 	set_pstate_pan(1);
1607 }
1608 #endif /* CONFIG_ARM64_PAN */
1609 
1610 #ifdef CONFIG_ARM64_RAS_EXTN
1611 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1612 {
1613 	/* Firmware may have left a deferred SError in this register. */
1614 	write_sysreg_s(0, SYS_DISR_EL1);
1615 }
1616 #endif /* CONFIG_ARM64_RAS_EXTN */
1617 
1618 #ifdef CONFIG_ARM64_PTR_AUTH
1619 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1620 {
1621 	int boot_val, sec_val;
1622 
1623 	/* We don't expect to be called with SCOPE_SYSTEM */
1624 	WARN_ON(scope == SCOPE_SYSTEM);
1625 	/*
1626 	 * The ptr-auth feature levels are not intercompatible with lower
1627 	 * levels. Hence we must match ptr-auth feature level of the secondary
1628 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1629 	 * from the sanitised register whereas direct register read is done for
1630 	 * the secondary CPUs.
1631 	 * The sanitised feature state is guaranteed to match that of the
1632 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1633 	 * a chance to update the state, with the capability.
1634 	 */
1635 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1636 					       entry->field_pos, entry->sign);
1637 	if (scope & SCOPE_BOOT_CPU)
1638 		return boot_val >= entry->min_field_value;
1639 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1640 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1641 					      entry->field_pos, entry->sign);
1642 	return sec_val == boot_val;
1643 }
1644 
1645 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1646 				     int scope)
1647 {
1648 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1649 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1650 }
1651 
1652 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1653 			     int __unused)
1654 {
1655 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1656 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1657 }
1658 #endif /* CONFIG_ARM64_PTR_AUTH */
1659 
1660 #ifdef CONFIG_ARM64_E0PD
1661 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1662 {
1663 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1664 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1665 }
1666 #endif /* CONFIG_ARM64_E0PD */
1667 
1668 #ifdef CONFIG_ARM64_PSEUDO_NMI
1669 static bool enable_pseudo_nmi;
1670 
1671 static int __init early_enable_pseudo_nmi(char *p)
1672 {
1673 	return strtobool(p, &enable_pseudo_nmi);
1674 }
1675 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1676 
1677 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1678 				   int scope)
1679 {
1680 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1681 }
1682 #endif
1683 
1684 #ifdef CONFIG_ARM64_BTI
1685 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1686 {
1687 	/*
1688 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1689 	 * function entry points using BR is a requirement for
1690 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1691 	 * So, be strict and forbid other BRs using other registers to
1692 	 * jump onto a PACIxSP instruction:
1693 	 */
1694 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1695 	isb();
1696 }
1697 #endif /* CONFIG_ARM64_BTI */
1698 
1699 #ifdef CONFIG_ARM64_MTE
1700 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1701 {
1702 	static bool cleared_zero_page = false;
1703 
1704 	/*
1705 	 * Clear the tags in the zero page. This needs to be done via the
1706 	 * linear map which has the Tagged attribute.
1707 	 */
1708 	if (!cleared_zero_page) {
1709 		cleared_zero_page = true;
1710 		mte_clear_page_tags(lm_alias(empty_zero_page));
1711 	}
1712 }
1713 #endif /* CONFIG_ARM64_MTE */
1714 
1715 /* Internal helper functions to match cpu capability type */
1716 static bool
1717 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1718 {
1719 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1720 }
1721 
1722 static bool
1723 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1724 {
1725 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1726 }
1727 
1728 static bool
1729 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1730 {
1731 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1732 }
1733 
1734 static const struct arm64_cpu_capabilities arm64_features[] = {
1735 	{
1736 		.desc = "GIC system register CPU interface",
1737 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1738 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1739 		.matches = has_useable_gicv3_cpuif,
1740 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1741 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1742 		.sign = FTR_UNSIGNED,
1743 		.min_field_value = 1,
1744 	},
1745 #ifdef CONFIG_ARM64_PAN
1746 	{
1747 		.desc = "Privileged Access Never",
1748 		.capability = ARM64_HAS_PAN,
1749 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1750 		.matches = has_cpuid_feature,
1751 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1752 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1753 		.sign = FTR_UNSIGNED,
1754 		.min_field_value = 1,
1755 		.cpu_enable = cpu_enable_pan,
1756 	},
1757 #endif /* CONFIG_ARM64_PAN */
1758 #ifdef CONFIG_ARM64_LSE_ATOMICS
1759 	{
1760 		.desc = "LSE atomic instructions",
1761 		.capability = ARM64_HAS_LSE_ATOMICS,
1762 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1763 		.matches = has_cpuid_feature,
1764 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1765 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1766 		.sign = FTR_UNSIGNED,
1767 		.min_field_value = 2,
1768 	},
1769 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1770 	{
1771 		.desc = "Software prefetching using PRFM",
1772 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1773 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1774 		.matches = has_no_hw_prefetch,
1775 	},
1776 #ifdef CONFIG_ARM64_VHE
1777 	{
1778 		.desc = "Virtualization Host Extensions",
1779 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1780 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1781 		.matches = runs_at_el2,
1782 		.cpu_enable = cpu_copy_el2regs,
1783 	},
1784 #endif	/* CONFIG_ARM64_VHE */
1785 	{
1786 		.desc = "32-bit EL0 Support",
1787 		.capability = ARM64_HAS_32BIT_EL0,
1788 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1789 		.matches = has_cpuid_feature,
1790 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1791 		.sign = FTR_UNSIGNED,
1792 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1793 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1794 	},
1795 #ifdef CONFIG_KVM
1796 	{
1797 		.desc = "32-bit EL1 Support",
1798 		.capability = ARM64_HAS_32BIT_EL1,
1799 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1800 		.matches = has_cpuid_feature,
1801 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1802 		.sign = FTR_UNSIGNED,
1803 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
1804 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
1805 	},
1806 #endif
1807 	{
1808 		.desc = "Kernel page table isolation (KPTI)",
1809 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1810 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1811 		/*
1812 		 * The ID feature fields below are used to indicate that
1813 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1814 		 * more details.
1815 		 */
1816 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1817 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1818 		.min_field_value = 1,
1819 		.matches = unmap_kernel_at_el0,
1820 		.cpu_enable = kpti_install_ng_mappings,
1821 	},
1822 	{
1823 		/* FP/SIMD is not implemented */
1824 		.capability = ARM64_HAS_NO_FPSIMD,
1825 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1826 		.min_field_value = 0,
1827 		.matches = has_no_fpsimd,
1828 	},
1829 #ifdef CONFIG_ARM64_PMEM
1830 	{
1831 		.desc = "Data cache clean to Point of Persistence",
1832 		.capability = ARM64_HAS_DCPOP,
1833 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1834 		.matches = has_cpuid_feature,
1835 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1836 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1837 		.min_field_value = 1,
1838 	},
1839 	{
1840 		.desc = "Data cache clean to Point of Deep Persistence",
1841 		.capability = ARM64_HAS_DCPODP,
1842 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1843 		.matches = has_cpuid_feature,
1844 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1845 		.sign = FTR_UNSIGNED,
1846 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1847 		.min_field_value = 2,
1848 	},
1849 #endif
1850 #ifdef CONFIG_ARM64_SVE
1851 	{
1852 		.desc = "Scalable Vector Extension",
1853 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1854 		.capability = ARM64_SVE,
1855 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1856 		.sign = FTR_UNSIGNED,
1857 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
1858 		.min_field_value = ID_AA64PFR0_SVE,
1859 		.matches = has_cpuid_feature,
1860 		.cpu_enable = sve_kernel_enable,
1861 	},
1862 #endif /* CONFIG_ARM64_SVE */
1863 #ifdef CONFIG_ARM64_RAS_EXTN
1864 	{
1865 		.desc = "RAS Extension Support",
1866 		.capability = ARM64_HAS_RAS_EXTN,
1867 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1868 		.matches = has_cpuid_feature,
1869 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1870 		.sign = FTR_UNSIGNED,
1871 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
1872 		.min_field_value = ID_AA64PFR0_RAS_V1,
1873 		.cpu_enable = cpu_clear_disr,
1874 	},
1875 #endif /* CONFIG_ARM64_RAS_EXTN */
1876 #ifdef CONFIG_ARM64_AMU_EXTN
1877 	{
1878 		/*
1879 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
1880 		 * Therefore, don't provide .desc as we don't want the detection
1881 		 * message to be shown until at least one CPU is detected to
1882 		 * support the feature.
1883 		 */
1884 		.capability = ARM64_HAS_AMU_EXTN,
1885 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1886 		.matches = has_amu,
1887 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1888 		.sign = FTR_UNSIGNED,
1889 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
1890 		.min_field_value = ID_AA64PFR0_AMU,
1891 		.cpu_enable = cpu_amu_enable,
1892 	},
1893 #endif /* CONFIG_ARM64_AMU_EXTN */
1894 	{
1895 		.desc = "Data cache clean to the PoU not required for I/D coherence",
1896 		.capability = ARM64_HAS_CACHE_IDC,
1897 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1898 		.matches = has_cache_idc,
1899 		.cpu_enable = cpu_emulate_effective_ctr,
1900 	},
1901 	{
1902 		.desc = "Instruction cache invalidation not required for I/D coherence",
1903 		.capability = ARM64_HAS_CACHE_DIC,
1904 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1905 		.matches = has_cache_dic,
1906 	},
1907 	{
1908 		.desc = "Stage-2 Force Write-Back",
1909 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1910 		.capability = ARM64_HAS_STAGE2_FWB,
1911 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1912 		.sign = FTR_UNSIGNED,
1913 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
1914 		.min_field_value = 1,
1915 		.matches = has_cpuid_feature,
1916 		.cpu_enable = cpu_has_fwb,
1917 	},
1918 	{
1919 		.desc = "ARMv8.4 Translation Table Level",
1920 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1921 		.capability = ARM64_HAS_ARMv8_4_TTL,
1922 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1923 		.sign = FTR_UNSIGNED,
1924 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
1925 		.min_field_value = 1,
1926 		.matches = has_cpuid_feature,
1927 	},
1928 	{
1929 		.desc = "TLB range maintenance instructions",
1930 		.capability = ARM64_HAS_TLB_RANGE,
1931 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1932 		.matches = has_cpuid_feature,
1933 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1934 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
1935 		.sign = FTR_UNSIGNED,
1936 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
1937 	},
1938 #ifdef CONFIG_ARM64_HW_AFDBM
1939 	{
1940 		/*
1941 		 * Since we turn this on always, we don't want the user to
1942 		 * think that the feature is available when it may not be.
1943 		 * So hide the description.
1944 		 *
1945 		 * .desc = "Hardware pagetable Dirty Bit Management",
1946 		 *
1947 		 */
1948 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1949 		.capability = ARM64_HW_DBM,
1950 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1951 		.sign = FTR_UNSIGNED,
1952 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
1953 		.min_field_value = 2,
1954 		.matches = has_hw_dbm,
1955 		.cpu_enable = cpu_enable_hw_dbm,
1956 	},
1957 #endif
1958 	{
1959 		.desc = "CRC32 instructions",
1960 		.capability = ARM64_HAS_CRC32,
1961 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1962 		.matches = has_cpuid_feature,
1963 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1964 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
1965 		.min_field_value = 1,
1966 	},
1967 	{
1968 		.desc = "Speculative Store Bypassing Safe (SSBS)",
1969 		.capability = ARM64_SSBS,
1970 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1971 		.matches = has_cpuid_feature,
1972 		.sys_reg = SYS_ID_AA64PFR1_EL1,
1973 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
1974 		.sign = FTR_UNSIGNED,
1975 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
1976 	},
1977 #ifdef CONFIG_ARM64_CNP
1978 	{
1979 		.desc = "Common not Private translations",
1980 		.capability = ARM64_HAS_CNP,
1981 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1982 		.matches = has_useable_cnp,
1983 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1984 		.sign = FTR_UNSIGNED,
1985 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
1986 		.min_field_value = 1,
1987 		.cpu_enable = cpu_enable_cnp,
1988 	},
1989 #endif
1990 	{
1991 		.desc = "Speculation barrier (SB)",
1992 		.capability = ARM64_HAS_SB,
1993 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1994 		.matches = has_cpuid_feature,
1995 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1996 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
1997 		.sign = FTR_UNSIGNED,
1998 		.min_field_value = 1,
1999 	},
2000 #ifdef CONFIG_ARM64_PTR_AUTH
2001 	{
2002 		.desc = "Address authentication (architected algorithm)",
2003 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2004 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2005 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2006 		.sign = FTR_UNSIGNED,
2007 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2008 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2009 		.matches = has_address_auth_cpucap,
2010 	},
2011 	{
2012 		.desc = "Address authentication (IMP DEF algorithm)",
2013 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2014 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2015 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2016 		.sign = FTR_UNSIGNED,
2017 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2018 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2019 		.matches = has_address_auth_cpucap,
2020 	},
2021 	{
2022 		.capability = ARM64_HAS_ADDRESS_AUTH,
2023 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2024 		.matches = has_address_auth_metacap,
2025 	},
2026 	{
2027 		.desc = "Generic authentication (architected algorithm)",
2028 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2029 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2030 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2031 		.sign = FTR_UNSIGNED,
2032 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2033 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2034 		.matches = has_cpuid_feature,
2035 	},
2036 	{
2037 		.desc = "Generic authentication (IMP DEF algorithm)",
2038 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2039 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2040 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2041 		.sign = FTR_UNSIGNED,
2042 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2043 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2044 		.matches = has_cpuid_feature,
2045 	},
2046 	{
2047 		.capability = ARM64_HAS_GENERIC_AUTH,
2048 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2049 		.matches = has_generic_auth,
2050 	},
2051 #endif /* CONFIG_ARM64_PTR_AUTH */
2052 #ifdef CONFIG_ARM64_PSEUDO_NMI
2053 	{
2054 		/*
2055 		 * Depends on having GICv3
2056 		 */
2057 		.desc = "IRQ priority masking",
2058 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2059 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2060 		.matches = can_use_gic_priorities,
2061 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2062 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2063 		.sign = FTR_UNSIGNED,
2064 		.min_field_value = 1,
2065 	},
2066 #endif
2067 #ifdef CONFIG_ARM64_E0PD
2068 	{
2069 		.desc = "E0PD",
2070 		.capability = ARM64_HAS_E0PD,
2071 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2072 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2073 		.sign = FTR_UNSIGNED,
2074 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2075 		.matches = has_cpuid_feature,
2076 		.min_field_value = 1,
2077 		.cpu_enable = cpu_enable_e0pd,
2078 	},
2079 #endif
2080 #ifdef CONFIG_ARCH_RANDOM
2081 	{
2082 		.desc = "Random Number Generator",
2083 		.capability = ARM64_HAS_RNG,
2084 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2085 		.matches = has_cpuid_feature,
2086 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2087 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2088 		.sign = FTR_UNSIGNED,
2089 		.min_field_value = 1,
2090 	},
2091 #endif
2092 #ifdef CONFIG_ARM64_BTI
2093 	{
2094 		.desc = "Branch Target Identification",
2095 		.capability = ARM64_BTI,
2096 #ifdef CONFIG_ARM64_BTI_KERNEL
2097 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2098 #else
2099 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2100 #endif
2101 		.matches = has_cpuid_feature,
2102 		.cpu_enable = bti_enable,
2103 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2104 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2105 		.min_field_value = ID_AA64PFR1_BT_BTI,
2106 		.sign = FTR_UNSIGNED,
2107 	},
2108 #endif
2109 #ifdef CONFIG_ARM64_MTE
2110 	{
2111 		.desc = "Memory Tagging Extension",
2112 		.capability = ARM64_MTE,
2113 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2114 		.matches = has_cpuid_feature,
2115 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2116 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2117 		.min_field_value = ID_AA64PFR1_MTE,
2118 		.sign = FTR_UNSIGNED,
2119 		.cpu_enable = cpu_enable_mte,
2120 	},
2121 #endif /* CONFIG_ARM64_MTE */
2122 	{
2123 		.desc = "RCpc load-acquire (LDAPR)",
2124 		.capability = ARM64_HAS_LDAPR,
2125 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2126 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2127 		.sign = FTR_UNSIGNED,
2128 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2129 		.matches = has_cpuid_feature,
2130 		.min_field_value = 1,
2131 	},
2132 	{},
2133 };
2134 
2135 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2136 		.matches = has_cpuid_feature,					\
2137 		.sys_reg = reg,							\
2138 		.field_pos = field,						\
2139 		.sign = s,							\
2140 		.min_field_value = min_value,
2141 
2142 #define __HWCAP_CAP(name, cap_type, cap)					\
2143 		.desc = name,							\
2144 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2145 		.hwcap_type = cap_type,						\
2146 		.hwcap = cap,							\
2147 
2148 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2149 	{									\
2150 		__HWCAP_CAP(#cap, cap_type, cap)				\
2151 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2152 	}
2153 
2154 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2155 	{									\
2156 		__HWCAP_CAP(#cap, cap_type, cap)				\
2157 		.matches = cpucap_multi_entry_cap_matches,			\
2158 		.match_list = list,						\
2159 	}
2160 
2161 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2162 	{									\
2163 		__HWCAP_CAP(#cap, cap_type, cap)				\
2164 		.matches = match,						\
2165 	}
2166 
2167 #ifdef CONFIG_ARM64_PTR_AUTH
2168 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2169 	{
2170 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2171 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2172 	},
2173 	{
2174 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2175 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2176 	},
2177 	{},
2178 };
2179 
2180 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2181 	{
2182 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2183 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2184 	},
2185 	{
2186 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2187 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2188 	},
2189 	{},
2190 };
2191 #endif
2192 
2193 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2194 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2195 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2196 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2197 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2198 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2199 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2200 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2201 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2202 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2203 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2204 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2205 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2206 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2207 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2208 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2209 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2210 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2211 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2212 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2213 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2214 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2215 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2216 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2217 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2218 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2219 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2220 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2221 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2222 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2223 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2224 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2225 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2226 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2227 #ifdef CONFIG_ARM64_SVE
2228 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2229 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2230 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2231 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2232 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2233 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2234 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2235 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2236 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2237 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2238 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2239 #endif
2240 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2241 #ifdef CONFIG_ARM64_BTI
2242 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2243 #endif
2244 #ifdef CONFIG_ARM64_PTR_AUTH
2245 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2246 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2247 #endif
2248 #ifdef CONFIG_ARM64_MTE
2249 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2250 #endif /* CONFIG_ARM64_MTE */
2251 	{},
2252 };
2253 
2254 #ifdef CONFIG_COMPAT
2255 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2256 {
2257 	/*
2258 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2259 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2260 	 * check is future proof, by making sure value is non-zero.
2261 	 */
2262 	u32 mvfr1;
2263 
2264 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2265 	if (scope == SCOPE_SYSTEM)
2266 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2267 	else
2268 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2269 
2270 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2271 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2272 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2273 }
2274 #endif
2275 
2276 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2277 #ifdef CONFIG_COMPAT
2278 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2279 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2280 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2281 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2282 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2283 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2284 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2285 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2286 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2287 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2288 #endif
2289 	{},
2290 };
2291 
2292 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2293 {
2294 	switch (cap->hwcap_type) {
2295 	case CAP_HWCAP:
2296 		cpu_set_feature(cap->hwcap);
2297 		break;
2298 #ifdef CONFIG_COMPAT
2299 	case CAP_COMPAT_HWCAP:
2300 		compat_elf_hwcap |= (u32)cap->hwcap;
2301 		break;
2302 	case CAP_COMPAT_HWCAP2:
2303 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2304 		break;
2305 #endif
2306 	default:
2307 		WARN_ON(1);
2308 		break;
2309 	}
2310 }
2311 
2312 /* Check if we have a particular HWCAP enabled */
2313 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2314 {
2315 	bool rc;
2316 
2317 	switch (cap->hwcap_type) {
2318 	case CAP_HWCAP:
2319 		rc = cpu_have_feature(cap->hwcap);
2320 		break;
2321 #ifdef CONFIG_COMPAT
2322 	case CAP_COMPAT_HWCAP:
2323 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2324 		break;
2325 	case CAP_COMPAT_HWCAP2:
2326 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2327 		break;
2328 #endif
2329 	default:
2330 		WARN_ON(1);
2331 		rc = false;
2332 	}
2333 
2334 	return rc;
2335 }
2336 
2337 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2338 {
2339 	/* We support emulation of accesses to CPU ID feature registers */
2340 	cpu_set_named_feature(CPUID);
2341 	for (; hwcaps->matches; hwcaps++)
2342 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2343 			cap_set_elf_hwcap(hwcaps);
2344 }
2345 
2346 static void update_cpu_capabilities(u16 scope_mask)
2347 {
2348 	int i;
2349 	const struct arm64_cpu_capabilities *caps;
2350 
2351 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2352 	for (i = 0; i < ARM64_NCAPS; i++) {
2353 		caps = cpu_hwcaps_ptrs[i];
2354 		if (!caps || !(caps->type & scope_mask) ||
2355 		    cpus_have_cap(caps->capability) ||
2356 		    !caps->matches(caps, cpucap_default_scope(caps)))
2357 			continue;
2358 
2359 		if (caps->desc)
2360 			pr_info("detected: %s\n", caps->desc);
2361 		cpus_set_cap(caps->capability);
2362 
2363 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2364 			set_bit(caps->capability, boot_capabilities);
2365 	}
2366 }
2367 
2368 /*
2369  * Enable all the available capabilities on this CPU. The capabilities
2370  * with BOOT_CPU scope are handled separately and hence skipped here.
2371  */
2372 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2373 {
2374 	int i;
2375 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2376 
2377 	for_each_available_cap(i) {
2378 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2379 
2380 		if (WARN_ON(!cap))
2381 			continue;
2382 
2383 		if (!(cap->type & non_boot_scope))
2384 			continue;
2385 
2386 		if (cap->cpu_enable)
2387 			cap->cpu_enable(cap);
2388 	}
2389 	return 0;
2390 }
2391 
2392 /*
2393  * Run through the enabled capabilities and enable() it on all active
2394  * CPUs
2395  */
2396 static void __init enable_cpu_capabilities(u16 scope_mask)
2397 {
2398 	int i;
2399 	const struct arm64_cpu_capabilities *caps;
2400 	bool boot_scope;
2401 
2402 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2403 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2404 
2405 	for (i = 0; i < ARM64_NCAPS; i++) {
2406 		unsigned int num;
2407 
2408 		caps = cpu_hwcaps_ptrs[i];
2409 		if (!caps || !(caps->type & scope_mask))
2410 			continue;
2411 		num = caps->capability;
2412 		if (!cpus_have_cap(num))
2413 			continue;
2414 
2415 		/* Ensure cpus_have_const_cap(num) works */
2416 		static_branch_enable(&cpu_hwcap_keys[num]);
2417 
2418 		if (boot_scope && caps->cpu_enable)
2419 			/*
2420 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2421 			 * before any secondary CPU boots. Thus, each secondary
2422 			 * will enable the capability as appropriate via
2423 			 * check_local_cpu_capabilities(). The only exception is
2424 			 * the boot CPU, for which the capability must be
2425 			 * enabled here. This approach avoids costly
2426 			 * stop_machine() calls for this case.
2427 			 */
2428 			caps->cpu_enable(caps);
2429 	}
2430 
2431 	/*
2432 	 * For all non-boot scope capabilities, use stop_machine()
2433 	 * as it schedules the work allowing us to modify PSTATE,
2434 	 * instead of on_each_cpu() which uses an IPI, giving us a
2435 	 * PSTATE that disappears when we return.
2436 	 */
2437 	if (!boot_scope)
2438 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2439 			     NULL, cpu_online_mask);
2440 }
2441 
2442 /*
2443  * Run through the list of capabilities to check for conflicts.
2444  * If the system has already detected a capability, take necessary
2445  * action on this CPU.
2446  */
2447 static void verify_local_cpu_caps(u16 scope_mask)
2448 {
2449 	int i;
2450 	bool cpu_has_cap, system_has_cap;
2451 	const struct arm64_cpu_capabilities *caps;
2452 
2453 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2454 
2455 	for (i = 0; i < ARM64_NCAPS; i++) {
2456 		caps = cpu_hwcaps_ptrs[i];
2457 		if (!caps || !(caps->type & scope_mask))
2458 			continue;
2459 
2460 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2461 		system_has_cap = cpus_have_cap(caps->capability);
2462 
2463 		if (system_has_cap) {
2464 			/*
2465 			 * Check if the new CPU misses an advertised feature,
2466 			 * which is not safe to miss.
2467 			 */
2468 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2469 				break;
2470 			/*
2471 			 * We have to issue cpu_enable() irrespective of
2472 			 * whether the CPU has it or not, as it is enabeld
2473 			 * system wide. It is upto the call back to take
2474 			 * appropriate action on this CPU.
2475 			 */
2476 			if (caps->cpu_enable)
2477 				caps->cpu_enable(caps);
2478 		} else {
2479 			/*
2480 			 * Check if the CPU has this capability if it isn't
2481 			 * safe to have when the system doesn't.
2482 			 */
2483 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2484 				break;
2485 		}
2486 	}
2487 
2488 	if (i < ARM64_NCAPS) {
2489 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2490 			smp_processor_id(), caps->capability,
2491 			caps->desc, system_has_cap, cpu_has_cap);
2492 
2493 		if (cpucap_panic_on_conflict(caps))
2494 			cpu_panic_kernel();
2495 		else
2496 			cpu_die_early();
2497 	}
2498 }
2499 
2500 /*
2501  * Check for CPU features that are used in early boot
2502  * based on the Boot CPU value.
2503  */
2504 static void check_early_cpu_features(void)
2505 {
2506 	verify_cpu_asid_bits();
2507 
2508 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2509 }
2510 
2511 static void
2512 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2513 {
2514 
2515 	for (; caps->matches; caps++)
2516 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2517 			pr_crit("CPU%d: missing HWCAP: %s\n",
2518 					smp_processor_id(), caps->desc);
2519 			cpu_die_early();
2520 		}
2521 }
2522 
2523 static void verify_sve_features(void)
2524 {
2525 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2526 	u64 zcr = read_zcr_features();
2527 
2528 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2529 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2530 
2531 	if (len < safe_len || sve_verify_vq_map()) {
2532 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2533 			smp_processor_id());
2534 		cpu_die_early();
2535 	}
2536 
2537 	/* Add checks on other ZCR bits here if necessary */
2538 }
2539 
2540 static void verify_hyp_capabilities(void)
2541 {
2542 	u64 safe_mmfr1, mmfr0, mmfr1;
2543 	int parange, ipa_max;
2544 	unsigned int safe_vmid_bits, vmid_bits;
2545 
2546 	if (!IS_ENABLED(CONFIG_KVM) || !IS_ENABLED(CONFIG_KVM_ARM_HOST))
2547 		return;
2548 
2549 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2550 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2551 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2552 
2553 	/* Verify VMID bits */
2554 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2555 	vmid_bits = get_vmid_bits(mmfr1);
2556 	if (vmid_bits < safe_vmid_bits) {
2557 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2558 		cpu_die_early();
2559 	}
2560 
2561 	/* Verify IPA range */
2562 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2563 				ID_AA64MMFR0_PARANGE_SHIFT);
2564 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2565 	if (ipa_max < get_kvm_ipa_limit()) {
2566 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2567 		cpu_die_early();
2568 	}
2569 }
2570 
2571 /*
2572  * Run through the enabled system capabilities and enable() it on this CPU.
2573  * The capabilities were decided based on the available CPUs at the boot time.
2574  * Any new CPU should match the system wide status of the capability. If the
2575  * new CPU doesn't have a capability which the system now has enabled, we
2576  * cannot do anything to fix it up and could cause unexpected failures. So
2577  * we park the CPU.
2578  */
2579 static void verify_local_cpu_capabilities(void)
2580 {
2581 	/*
2582 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2583 	 * check_early_cpu_features(), as they need to be verified
2584 	 * on all secondary CPUs.
2585 	 */
2586 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2587 
2588 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
2589 
2590 	if (system_supports_32bit_el0())
2591 		verify_local_elf_hwcaps(compat_elf_hwcaps);
2592 
2593 	if (system_supports_sve())
2594 		verify_sve_features();
2595 
2596 	if (is_hyp_mode_available())
2597 		verify_hyp_capabilities();
2598 }
2599 
2600 void check_local_cpu_capabilities(void)
2601 {
2602 	/*
2603 	 * All secondary CPUs should conform to the early CPU features
2604 	 * in use by the kernel based on boot CPU.
2605 	 */
2606 	check_early_cpu_features();
2607 
2608 	/*
2609 	 * If we haven't finalised the system capabilities, this CPU gets
2610 	 * a chance to update the errata work arounds and local features.
2611 	 * Otherwise, this CPU should verify that it has all the system
2612 	 * advertised capabilities.
2613 	 */
2614 	if (!system_capabilities_finalized())
2615 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2616 	else
2617 		verify_local_cpu_capabilities();
2618 }
2619 
2620 static void __init setup_boot_cpu_capabilities(void)
2621 {
2622 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2623 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2624 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2625 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2626 }
2627 
2628 bool this_cpu_has_cap(unsigned int n)
2629 {
2630 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2631 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2632 
2633 		if (cap)
2634 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2635 	}
2636 
2637 	return false;
2638 }
2639 
2640 /*
2641  * This helper function is used in a narrow window when,
2642  * - The system wide safe registers are set with all the SMP CPUs and,
2643  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2644  * In all other cases cpus_have_{const_}cap() should be used.
2645  */
2646 static bool __maybe_unused __system_matches_cap(unsigned int n)
2647 {
2648 	if (n < ARM64_NCAPS) {
2649 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2650 
2651 		if (cap)
2652 			return cap->matches(cap, SCOPE_SYSTEM);
2653 	}
2654 	return false;
2655 }
2656 
2657 void cpu_set_feature(unsigned int num)
2658 {
2659 	WARN_ON(num >= MAX_CPU_FEATURES);
2660 	elf_hwcap |= BIT(num);
2661 }
2662 EXPORT_SYMBOL_GPL(cpu_set_feature);
2663 
2664 bool cpu_have_feature(unsigned int num)
2665 {
2666 	WARN_ON(num >= MAX_CPU_FEATURES);
2667 	return elf_hwcap & BIT(num);
2668 }
2669 EXPORT_SYMBOL_GPL(cpu_have_feature);
2670 
2671 unsigned long cpu_get_elf_hwcap(void)
2672 {
2673 	/*
2674 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2675 	 * note that for userspace compatibility we guarantee that bits 62
2676 	 * and 63 will always be returned as 0.
2677 	 */
2678 	return lower_32_bits(elf_hwcap);
2679 }
2680 
2681 unsigned long cpu_get_elf_hwcap2(void)
2682 {
2683 	return upper_32_bits(elf_hwcap);
2684 }
2685 
2686 static void __init setup_system_capabilities(void)
2687 {
2688 	/*
2689 	 * We have finalised the system-wide safe feature
2690 	 * registers, finalise the capabilities that depend
2691 	 * on it. Also enable all the available capabilities,
2692 	 * that are not enabled already.
2693 	 */
2694 	update_cpu_capabilities(SCOPE_SYSTEM);
2695 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2696 }
2697 
2698 void __init setup_cpu_features(void)
2699 {
2700 	u32 cwg;
2701 
2702 	setup_system_capabilities();
2703 	setup_elf_hwcaps(arm64_elf_hwcaps);
2704 
2705 	if (system_supports_32bit_el0())
2706 		setup_elf_hwcaps(compat_elf_hwcaps);
2707 
2708 	if (system_uses_ttbr0_pan())
2709 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2710 
2711 	sve_setup();
2712 	minsigstksz_setup();
2713 
2714 	/* Advertise that we have computed the system capabilities */
2715 	finalize_system_capabilities();
2716 
2717 	/*
2718 	 * Check for sane CTR_EL0.CWG value.
2719 	 */
2720 	cwg = cache_type_cwg();
2721 	if (!cwg)
2722 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2723 			ARCH_DMA_MINALIGN);
2724 }
2725 
2726 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2727 {
2728 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2729 }
2730 
2731 /*
2732  * We emulate only the following system register space.
2733  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2734  * See Table C5-6 System instruction encodings for System register accesses,
2735  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2736  */
2737 static inline bool __attribute_const__ is_emulated(u32 id)
2738 {
2739 	return (sys_reg_Op0(id) == 0x3 &&
2740 		sys_reg_CRn(id) == 0x0 &&
2741 		sys_reg_Op1(id) == 0x0 &&
2742 		(sys_reg_CRm(id) == 0 ||
2743 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2744 }
2745 
2746 /*
2747  * With CRm == 0, reg should be one of :
2748  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2749  */
2750 static inline int emulate_id_reg(u32 id, u64 *valp)
2751 {
2752 	switch (id) {
2753 	case SYS_MIDR_EL1:
2754 		*valp = read_cpuid_id();
2755 		break;
2756 	case SYS_MPIDR_EL1:
2757 		*valp = SYS_MPIDR_SAFE_VAL;
2758 		break;
2759 	case SYS_REVIDR_EL1:
2760 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2761 		*valp = 0;
2762 		break;
2763 	default:
2764 		return -EINVAL;
2765 	}
2766 
2767 	return 0;
2768 }
2769 
2770 static int emulate_sys_reg(u32 id, u64 *valp)
2771 {
2772 	struct arm64_ftr_reg *regp;
2773 
2774 	if (!is_emulated(id))
2775 		return -EINVAL;
2776 
2777 	if (sys_reg_CRm(id) == 0)
2778 		return emulate_id_reg(id, valp);
2779 
2780 	regp = get_arm64_ftr_reg_nowarn(id);
2781 	if (regp)
2782 		*valp = arm64_ftr_reg_user_value(regp);
2783 	else
2784 		/*
2785 		 * The untracked registers are either IMPLEMENTATION DEFINED
2786 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2787 		 */
2788 		*valp = 0;
2789 	return 0;
2790 }
2791 
2792 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2793 {
2794 	int rc;
2795 	u64 val;
2796 
2797 	rc = emulate_sys_reg(sys_reg, &val);
2798 	if (!rc) {
2799 		pt_regs_write_reg(regs, rt, val);
2800 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2801 	}
2802 	return rc;
2803 }
2804 
2805 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2806 {
2807 	u32 sys_reg, rt;
2808 
2809 	/*
2810 	 * sys_reg values are defined as used in mrs/msr instruction.
2811 	 * shift the imm value to get the encoding.
2812 	 */
2813 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2814 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2815 	return do_emulate_mrs(regs, sys_reg, rt);
2816 }
2817 
2818 static struct undef_hook mrs_hook = {
2819 	.instr_mask = 0xfff00000,
2820 	.instr_val  = 0xd5300000,
2821 	.pstate_mask = PSR_AA32_MODE_MASK,
2822 	.pstate_val = PSR_MODE_EL0t,
2823 	.fn = emulate_mrs,
2824 };
2825 
2826 static int __init enable_mrs_emulation(void)
2827 {
2828 	register_undef_hook(&mrs_hook);
2829 	return 0;
2830 }
2831 
2832 core_initcall(enable_mrs_emulation);
2833 
2834 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
2835 			  char *buf)
2836 {
2837 	if (__meltdown_safe)
2838 		return sprintf(buf, "Not affected\n");
2839 
2840 	if (arm64_kernel_unmapped_at_el0())
2841 		return sprintf(buf, "Mitigation: PTI\n");
2842 
2843 	return sprintf(buf, "Vulnerable\n");
2844 }
2845