xref: /openbmc/linux/arch/arm64/kernel/cpufeature.c (revision 9cf0666f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Contains CPU feature definitions
4  *
5  * Copyright (C) 2015 ARM Ltd.
6  *
7  * A note for the weary kernel hacker: the code here is confusing and hard to
8  * follow! That's partly because it's solving a nasty problem, but also because
9  * there's a little bit of over-abstraction that tends to obscure what's going
10  * on behind a maze of helper functions and macros.
11  *
12  * The basic problem is that hardware folks have started gluing together CPUs
13  * with distinct architectural features; in some cases even creating SoCs where
14  * user-visible instructions are available only on a subset of the available
15  * cores. We try to address this by snapshotting the feature registers of the
16  * boot CPU and comparing these with the feature registers of each secondary
17  * CPU when bringing them up. If there is a mismatch, then we update the
18  * snapshot state to indicate the lowest-common denominator of the feature,
19  * known as the "safe" value. This snapshot state can be queried to view the
20  * "sanitised" value of a feature register.
21  *
22  * The sanitised register values are used to decide which capabilities we
23  * have in the system. These may be in the form of traditional "hwcaps"
24  * advertised to userspace or internal "cpucaps" which are used to configure
25  * things like alternative patching and static keys. While a feature mismatch
26  * may result in a TAINT_CPU_OUT_OF_SPEC kernel taint, a capability mismatch
27  * may prevent a CPU from being onlined at all.
28  *
29  * Some implementation details worth remembering:
30  *
31  * - Mismatched features are *always* sanitised to a "safe" value, which
32  *   usually indicates that the feature is not supported.
33  *
34  * - A mismatched feature marked with FTR_STRICT will cause a "SANITY CHECK"
35  *   warning when onlining an offending CPU and the kernel will be tainted
36  *   with TAINT_CPU_OUT_OF_SPEC.
37  *
38  * - Features marked as FTR_VISIBLE have their sanitised value visible to
39  *   userspace. FTR_VISIBLE features in registers that are only visible
40  *   to EL0 by trapping *must* have a corresponding HWCAP so that late
41  *   onlining of CPUs cannot lead to features disappearing at runtime.
42  *
43  * - A "feature" is typically a 4-bit register field. A "capability" is the
44  *   high-level description derived from the sanitised field value.
45  *
46  * - Read the Arm ARM (DDI 0487F.a) section D13.1.3 ("Principles of the ID
47  *   scheme for fields in ID registers") to understand when feature fields
48  *   may be signed or unsigned (FTR_SIGNED and FTR_UNSIGNED accordingly).
49  *
50  * - KVM exposes its own view of the feature registers to guest operating
51  *   systems regardless of FTR_VISIBLE. This is typically driven from the
52  *   sanitised register values to allow virtual CPUs to be migrated between
53  *   arbitrary physical CPUs, but some features not present on the host are
54  *   also advertised and emulated. Look at sys_reg_descs[] for the gory
55  *   details.
56  *
57  * - If the arm64_ftr_bits[] for a register has a missing field, then this
58  *   field is treated as STRICT RES0, including for read_sanitised_ftr_reg().
59  *   This is stronger than FTR_HIDDEN and can be used to hide features from
60  *   KVM guests.
61  */
62 
63 #define pr_fmt(fmt) "CPU features: " fmt
64 
65 #include <linux/bsearch.h>
66 #include <linux/cpumask.h>
67 #include <linux/crash_dump.h>
68 #include <linux/sort.h>
69 #include <linux/stop_machine.h>
70 #include <linux/sysfs.h>
71 #include <linux/types.h>
72 #include <linux/minmax.h>
73 #include <linux/mm.h>
74 #include <linux/cpu.h>
75 #include <linux/kasan.h>
76 #include <asm/cpu.h>
77 #include <asm/cpufeature.h>
78 #include <asm/cpu_ops.h>
79 #include <asm/fpsimd.h>
80 #include <asm/insn.h>
81 #include <asm/kvm_host.h>
82 #include <asm/mmu_context.h>
83 #include <asm/mte.h>
84 #include <asm/processor.h>
85 #include <asm/smp.h>
86 #include <asm/sysreg.h>
87 #include <asm/traps.h>
88 #include <asm/virt.h>
89 
90 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
91 static unsigned long elf_hwcap __read_mostly;
92 
93 #ifdef CONFIG_COMPAT
94 #define COMPAT_ELF_HWCAP_DEFAULT	\
95 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
96 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
97 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
98 				 COMPAT_HWCAP_LPAE)
99 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
100 unsigned int compat_elf_hwcap2 __read_mostly;
101 #endif
102 
103 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
104 EXPORT_SYMBOL(cpu_hwcaps);
105 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
106 
107 /* Need also bit for ARM64_CB_PATCH */
108 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
109 
110 bool arm64_use_ng_mappings = false;
111 EXPORT_SYMBOL(arm64_use_ng_mappings);
112 
113 /*
114  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
115  * support it?
116  */
117 static bool __read_mostly allow_mismatched_32bit_el0;
118 
119 /*
120  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
121  * seen at least one CPU capable of 32-bit EL0.
122  */
123 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
124 
125 /*
126  * Mask of CPUs supporting 32-bit EL0.
127  * Only valid if arm64_mismatched_32bit_el0 is enabled.
128  */
129 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
130 
131 /*
132  * Flag to indicate if we have computed the system wide
133  * capabilities based on the boot time active CPUs. This
134  * will be used to determine if a new booting CPU should
135  * go through the verification process to make sure that it
136  * supports the system capabilities, without using a hotplug
137  * notifier. This is also used to decide if we could use
138  * the fast path for checking constant CPU caps.
139  */
140 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
141 EXPORT_SYMBOL(arm64_const_caps_ready);
142 static inline void finalize_system_capabilities(void)
143 {
144 	static_branch_enable(&arm64_const_caps_ready);
145 }
146 
147 void dump_cpu_features(void)
148 {
149 	/* file-wide pr_fmt adds "CPU features: " prefix */
150 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
151 }
152 
153 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
154 EXPORT_SYMBOL(cpu_hwcap_keys);
155 
156 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
157 	{						\
158 		.sign = SIGNED,				\
159 		.visible = VISIBLE,			\
160 		.strict = STRICT,			\
161 		.type = TYPE,				\
162 		.shift = SHIFT,				\
163 		.width = WIDTH,				\
164 		.safe_val = SAFE_VAL,			\
165 	}
166 
167 /* Define a feature with unsigned values */
168 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
169 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
170 
171 /* Define a feature with a signed value */
172 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
173 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
174 
175 #define ARM64_FTR_END					\
176 	{						\
177 		.width = 0,				\
178 	}
179 
180 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
181 
182 static bool __system_matches_cap(unsigned int n);
183 
184 /*
185  * NOTE: Any changes to the visibility of features should be kept in
186  * sync with the documentation of the CPU feature register ABI.
187  */
188 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
189 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
190 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
191 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
192 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
203 	ARM64_FTR_END,
204 };
205 
206 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
211 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
212 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
213 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
214 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
216 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
221 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
223 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
225 	ARM64_FTR_END,
226 };
227 
228 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
229 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
231 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
232 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
233 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
235 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
236 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
238 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
239 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
240 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
244 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_ELx_64BIT_ONLY),
245 	ARM64_FTR_END,
246 };
247 
248 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
249 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
251 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
252 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
253 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
254 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
255 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
256 	ARM64_FTR_END,
257 };
258 
259 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
260 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
261 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
263 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
264 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
265 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
266 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
267 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
268 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
269 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
270 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
271 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
272 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
273 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
274 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
275 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
276 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
277 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
278 	ARM64_FTR_END,
279 };
280 
281 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
282 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
284 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
285 	/*
286 	 * Page size not being supported at Stage-2 is not fatal. You
287 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
288 	 * your favourite nesting hypervisor.
289 	 *
290 	 * There is a small corner case where the hypervisor explicitly
291 	 * advertises a given granule size at Stage-2 (value 2) on some
292 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
293 	 * vCPUs. Although this is not forbidden by the architecture, it
294 	 * indicates that the hypervisor is being silly (or buggy).
295 	 *
296 	 * We make no effort to cope with this and pretend that if these
297 	 * fields are inconsistent across vCPUs, then it isn't worth
298 	 * trying to bring KVM up.
299 	 */
300 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
301 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
302 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
303 	/*
304 	 * We already refuse to boot CPUs that don't support our configured
305 	 * page size, so we can only detect mismatches for a page size other
306 	 * than the one we're currently using. Unfortunately, SoCs like this
307 	 * exist in the wild so, even though we don't like it, we'll have to go
308 	 * along with it and treat them as non-strict.
309 	 */
310 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
311 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
312 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
313 
314 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
315 	/* Linux shouldn't care about secure memory */
316 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
317 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
318 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
319 	/*
320 	 * Differing PARange is fine as long as all peripherals and memory are mapped
321 	 * within the minimum PARange of all CPUs
322 	 */
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
324 	ARM64_FTR_END,
325 };
326 
327 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
330 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
331 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
332 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
333 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
334 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
335 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
338 	ARM64_FTR_END,
339 };
340 
341 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
347 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
348 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
351 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
352 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
353 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
354 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
356 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
357 	ARM64_FTR_END,
358 };
359 
360 static const struct arm64_ftr_bits ftr_ctr[] = {
361 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
362 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
363 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
364 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
365 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
367 	/*
368 	 * Linux can handle differing I-cache policies. Userspace JITs will
369 	 * make use of *minLine.
370 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
371 	 */
372 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
373 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
374 	ARM64_FTR_END,
375 };
376 
377 static struct arm64_ftr_override __ro_after_init no_override = { };
378 
379 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
380 	.name		= "SYS_CTR_EL0",
381 	.ftr_bits	= ftr_ctr,
382 	.override	= &no_override,
383 };
384 
385 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
386 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
390 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
391 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
393 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
394 	ARM64_FTR_END,
395 };
396 
397 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
398 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
399 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
402 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
403 	/*
404 	 * We can instantiate multiple PMU instances with different levels
405 	 * of support.
406 	 */
407 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
408 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
409 	ARM64_FTR_END,
410 };
411 
412 static const struct arm64_ftr_bits ftr_mvfr2[] = {
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
415 	ARM64_FTR_END,
416 };
417 
418 static const struct arm64_ftr_bits ftr_dczid[] = {
419 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
420 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
421 	ARM64_FTR_END,
422 };
423 
424 static const struct arm64_ftr_bits ftr_gmid[] = {
425 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, SYS_GMID_EL1_BS_SHIFT, 4, 0),
426 	ARM64_FTR_END,
427 };
428 
429 static const struct arm64_ftr_bits ftr_id_isar0[] = {
430 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
431 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
432 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
433 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
434 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
435 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
436 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
437 	ARM64_FTR_END,
438 };
439 
440 static const struct arm64_ftr_bits ftr_id_isar5[] = {
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
444 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
446 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
447 	ARM64_FTR_END,
448 };
449 
450 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
458 
459 	/*
460 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
461 	 * external abort on speculative read. It is safe to assume that an
462 	 * SError might be generated than it will not be. Hence it has been
463 	 * classified as FTR_HIGHER_SAFE.
464 	 */
465 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
466 	ARM64_FTR_END,
467 };
468 
469 static const struct arm64_ftr_bits ftr_id_isar4[] = {
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
473 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
474 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
475 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
476 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
478 	ARM64_FTR_END,
479 };
480 
481 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
483 	ARM64_FTR_END,
484 };
485 
486 static const struct arm64_ftr_bits ftr_id_isar6[] = {
487 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
489 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
490 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
491 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
492 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
494 	ARM64_FTR_END,
495 };
496 
497 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
501 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
503 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
504 	ARM64_FTR_END,
505 };
506 
507 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
516 	ARM64_FTR_END,
517 };
518 
519 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
521 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
522 	ARM64_FTR_END,
523 };
524 
525 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
526 	/* [31:28] TraceFilt */
527 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
531 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
532 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
533 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
534 	ARM64_FTR_END,
535 };
536 
537 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
538 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
539 	ARM64_FTR_END,
540 };
541 
542 static const struct arm64_ftr_bits ftr_zcr[] = {
543 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
544 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
545 	ARM64_FTR_END,
546 };
547 
548 /*
549  * Common ftr bits for a 32bit register with all hidden, strict
550  * attributes, with 4bit feature fields and a default safe value of
551  * 0. Covers the following 32bit registers:
552  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
553  */
554 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
555 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
556 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
557 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
558 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
559 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
560 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
561 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
562 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
563 	ARM64_FTR_END,
564 };
565 
566 /* Table for a single 32bit feature value */
567 static const struct arm64_ftr_bits ftr_single32[] = {
568 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
569 	ARM64_FTR_END,
570 };
571 
572 static const struct arm64_ftr_bits ftr_raz[] = {
573 	ARM64_FTR_END,
574 };
575 
576 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
577 		.sys_id = id,					\
578 		.reg = 	&(struct arm64_ftr_reg){		\
579 			.name = id_str,				\
580 			.override = (ovr),			\
581 			.ftr_bits = &((table)[0]),		\
582 	}}
583 
584 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
585 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
586 
587 #define ARM64_FTR_REG(id, table)		\
588 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
589 
590 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
591 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
592 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
593 
594 static const struct __ftr_reg_entry {
595 	u32			sys_id;
596 	struct arm64_ftr_reg 	*reg;
597 } arm64_ftr_regs[] = {
598 
599 	/* Op1 = 0, CRn = 0, CRm = 1 */
600 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
601 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
602 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
603 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
604 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
605 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
606 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
607 
608 	/* Op1 = 0, CRn = 0, CRm = 2 */
609 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
610 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
611 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
612 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
613 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
614 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
615 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
616 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
617 
618 	/* Op1 = 0, CRn = 0, CRm = 3 */
619 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
620 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
621 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
622 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
623 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
624 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
625 
626 	/* Op1 = 0, CRn = 0, CRm = 4 */
627 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
628 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
629 			       &id_aa64pfr1_override),
630 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
631 
632 	/* Op1 = 0, CRn = 0, CRm = 5 */
633 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
634 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
635 
636 	/* Op1 = 0, CRn = 0, CRm = 6 */
637 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
638 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
639 			       &id_aa64isar1_override),
640 
641 	/* Op1 = 0, CRn = 0, CRm = 7 */
642 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
643 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
644 			       &id_aa64mmfr1_override),
645 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
646 
647 	/* Op1 = 0, CRn = 1, CRm = 2 */
648 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
649 
650 	/* Op1 = 1, CRn = 0, CRm = 0 */
651 	ARM64_FTR_REG(SYS_GMID_EL1, ftr_gmid),
652 
653 	/* Op1 = 3, CRn = 0, CRm = 0 */
654 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
655 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
656 
657 	/* Op1 = 3, CRn = 14, CRm = 0 */
658 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
659 };
660 
661 static int search_cmp_ftr_reg(const void *id, const void *regp)
662 {
663 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
664 }
665 
666 /*
667  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
668  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
669  * ascending order of sys_id, we use binary search to find a matching
670  * entry.
671  *
672  * returns - Upon success,  matching ftr_reg entry for id.
673  *         - NULL on failure. It is upto the caller to decide
674  *	     the impact of a failure.
675  */
676 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
677 {
678 	const struct __ftr_reg_entry *ret;
679 
680 	ret = bsearch((const void *)(unsigned long)sys_id,
681 			arm64_ftr_regs,
682 			ARRAY_SIZE(arm64_ftr_regs),
683 			sizeof(arm64_ftr_regs[0]),
684 			search_cmp_ftr_reg);
685 	if (ret)
686 		return ret->reg;
687 	return NULL;
688 }
689 
690 /*
691  * get_arm64_ftr_reg - Looks up a feature register entry using
692  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
693  *
694  * returns - Upon success,  matching ftr_reg entry for id.
695  *         - NULL on failure but with an WARN_ON().
696  */
697 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
698 {
699 	struct arm64_ftr_reg *reg;
700 
701 	reg = get_arm64_ftr_reg_nowarn(sys_id);
702 
703 	/*
704 	 * Requesting a non-existent register search is an error. Warn
705 	 * and let the caller handle it.
706 	 */
707 	WARN_ON(!reg);
708 	return reg;
709 }
710 
711 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
712 			       s64 ftr_val)
713 {
714 	u64 mask = arm64_ftr_mask(ftrp);
715 
716 	reg &= ~mask;
717 	reg |= (ftr_val << ftrp->shift) & mask;
718 	return reg;
719 }
720 
721 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
722 				s64 cur)
723 {
724 	s64 ret = 0;
725 
726 	switch (ftrp->type) {
727 	case FTR_EXACT:
728 		ret = ftrp->safe_val;
729 		break;
730 	case FTR_LOWER_SAFE:
731 		ret = min(new, cur);
732 		break;
733 	case FTR_HIGHER_OR_ZERO_SAFE:
734 		if (!cur || !new)
735 			break;
736 		fallthrough;
737 	case FTR_HIGHER_SAFE:
738 		ret = max(new, cur);
739 		break;
740 	default:
741 		BUG();
742 	}
743 
744 	return ret;
745 }
746 
747 static void __init sort_ftr_regs(void)
748 {
749 	unsigned int i;
750 
751 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
752 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
753 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
754 		unsigned int j = 0;
755 
756 		/*
757 		 * Features here must be sorted in descending order with respect
758 		 * to their shift values and should not overlap with each other.
759 		 */
760 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
761 			unsigned int width = ftr_reg->ftr_bits[j].width;
762 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
763 			unsigned int prev_shift;
764 
765 			WARN((shift  + width) > 64,
766 				"%s has invalid feature at shift %d\n",
767 				ftr_reg->name, shift);
768 
769 			/*
770 			 * Skip the first feature. There is nothing to
771 			 * compare against for now.
772 			 */
773 			if (j == 0)
774 				continue;
775 
776 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
777 			WARN((shift + width) > prev_shift,
778 				"%s has feature overlap at shift %d\n",
779 				ftr_reg->name, shift);
780 		}
781 
782 		/*
783 		 * Skip the first register. There is nothing to
784 		 * compare against for now.
785 		 */
786 		if (i == 0)
787 			continue;
788 		/*
789 		 * Registers here must be sorted in ascending order with respect
790 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
791 		 * to work correctly.
792 		 */
793 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
794 	}
795 }
796 
797 /*
798  * Initialise the CPU feature register from Boot CPU values.
799  * Also initiliases the strict_mask for the register.
800  * Any bits that are not covered by an arm64_ftr_bits entry are considered
801  * RES0 for the system-wide value, and must strictly match.
802  */
803 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
804 {
805 	u64 val = 0;
806 	u64 strict_mask = ~0x0ULL;
807 	u64 user_mask = 0;
808 	u64 valid_mask = 0;
809 
810 	const struct arm64_ftr_bits *ftrp;
811 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
812 
813 	if (!reg)
814 		return;
815 
816 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
817 		u64 ftr_mask = arm64_ftr_mask(ftrp);
818 		s64 ftr_new = arm64_ftr_value(ftrp, new);
819 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
820 
821 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
822 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
823 			char *str = NULL;
824 
825 			if (ftr_ovr != tmp) {
826 				/* Unsafe, remove the override */
827 				reg->override->mask &= ~ftr_mask;
828 				reg->override->val &= ~ftr_mask;
829 				tmp = ftr_ovr;
830 				str = "ignoring override";
831 			} else if (ftr_new != tmp) {
832 				/* Override was valid */
833 				ftr_new = tmp;
834 				str = "forced";
835 			} else if (ftr_ovr == tmp) {
836 				/* Override was the safe value */
837 				str = "already set";
838 			}
839 
840 			if (str)
841 				pr_warn("%s[%d:%d]: %s to %llx\n",
842 					reg->name,
843 					ftrp->shift + ftrp->width - 1,
844 					ftrp->shift, str, tmp);
845 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
846 			reg->override->val &= ~ftr_mask;
847 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
848 				reg->name,
849 				ftrp->shift + ftrp->width - 1,
850 				ftrp->shift);
851 		}
852 
853 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
854 
855 		valid_mask |= ftr_mask;
856 		if (!ftrp->strict)
857 			strict_mask &= ~ftr_mask;
858 		if (ftrp->visible)
859 			user_mask |= ftr_mask;
860 		else
861 			reg->user_val = arm64_ftr_set_value(ftrp,
862 							    reg->user_val,
863 							    ftrp->safe_val);
864 	}
865 
866 	val &= valid_mask;
867 
868 	reg->sys_val = val;
869 	reg->strict_mask = strict_mask;
870 	reg->user_mask = user_mask;
871 }
872 
873 extern const struct arm64_cpu_capabilities arm64_errata[];
874 static const struct arm64_cpu_capabilities arm64_features[];
875 
876 static void __init
877 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
878 {
879 	for (; caps->matches; caps++) {
880 		if (WARN(caps->capability >= ARM64_NCAPS,
881 			"Invalid capability %d\n", caps->capability))
882 			continue;
883 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
884 			"Duplicate entry for capability %d\n",
885 			caps->capability))
886 			continue;
887 		cpu_hwcaps_ptrs[caps->capability] = caps;
888 	}
889 }
890 
891 static void __init init_cpu_hwcaps_indirect_list(void)
892 {
893 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
894 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
895 }
896 
897 static void __init setup_boot_cpu_capabilities(void);
898 
899 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
900 {
901 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
902 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
903 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
904 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
905 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
906 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
907 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
908 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
909 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
910 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
911 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
912 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
913 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
914 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
915 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
916 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
917 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
918 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
919 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
920 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
921 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
922 }
923 
924 void __init init_cpu_features(struct cpuinfo_arm64 *info)
925 {
926 	/* Before we start using the tables, make sure it is sorted */
927 	sort_ftr_regs();
928 
929 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
930 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
931 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
932 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
933 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
934 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
935 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
936 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
937 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
938 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
939 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
940 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
941 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
942 
943 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
944 		init_32bit_cpu_features(&info->aarch32);
945 
946 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
947 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
948 		vec_init_vq_map(ARM64_VEC_SVE);
949 	}
950 
951 	if (id_aa64pfr1_mte(info->reg_id_aa64pfr1))
952 		init_cpu_ftr_reg(SYS_GMID_EL1, info->reg_gmid);
953 
954 	/*
955 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
956 	 * before we handle the boot CPU below.
957 	 */
958 	init_cpu_hwcaps_indirect_list();
959 
960 	/*
961 	 * Detect and enable early CPU capabilities based on the boot CPU,
962 	 * after we have initialised the CPU feature infrastructure.
963 	 */
964 	setup_boot_cpu_capabilities();
965 }
966 
967 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
968 {
969 	const struct arm64_ftr_bits *ftrp;
970 
971 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
972 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
973 		s64 ftr_new = arm64_ftr_value(ftrp, new);
974 
975 		if (ftr_cur == ftr_new)
976 			continue;
977 		/* Find a safe value */
978 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
979 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
980 	}
981 
982 }
983 
984 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
985 {
986 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
987 
988 	if (!regp)
989 		return 0;
990 
991 	update_cpu_ftr_reg(regp, val);
992 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
993 		return 0;
994 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
995 			regp->name, boot, cpu, val);
996 	return 1;
997 }
998 
999 static void relax_cpu_ftr_reg(u32 sys_id, int field)
1000 {
1001 	const struct arm64_ftr_bits *ftrp;
1002 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1003 
1004 	if (!regp)
1005 		return;
1006 
1007 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1008 		if (ftrp->shift == field) {
1009 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1010 			break;
1011 		}
1012 	}
1013 
1014 	/* Bogus field? */
1015 	WARN_ON(!ftrp->width);
1016 }
1017 
1018 static void lazy_init_32bit_cpu_features(struct cpuinfo_arm64 *info,
1019 					 struct cpuinfo_arm64 *boot)
1020 {
1021 	static bool boot_cpu_32bit_regs_overridden = false;
1022 
1023 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1024 		return;
1025 
1026 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1027 		return;
1028 
1029 	boot->aarch32 = info->aarch32;
1030 	init_32bit_cpu_features(&boot->aarch32);
1031 	boot_cpu_32bit_regs_overridden = true;
1032 }
1033 
1034 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1035 				     struct cpuinfo_32bit *boot)
1036 {
1037 	int taint = 0;
1038 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1039 
1040 	/*
1041 	 * If we don't have AArch32 at EL1, then relax the strictness of
1042 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1043 	 */
1044 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1045 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1046 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1047 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1048 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1049 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1050 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1051 	}
1052 
1053 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1054 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1055 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1056 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1057 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1058 				      info->reg_id_isar0, boot->reg_id_isar0);
1059 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1060 				      info->reg_id_isar1, boot->reg_id_isar1);
1061 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1062 				      info->reg_id_isar2, boot->reg_id_isar2);
1063 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1064 				      info->reg_id_isar3, boot->reg_id_isar3);
1065 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1066 				      info->reg_id_isar4, boot->reg_id_isar4);
1067 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1068 				      info->reg_id_isar5, boot->reg_id_isar5);
1069 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1070 				      info->reg_id_isar6, boot->reg_id_isar6);
1071 
1072 	/*
1073 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1074 	 * ACTLR formats could differ across CPUs and therefore would have to
1075 	 * be trapped for virtualization anyway.
1076 	 */
1077 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1078 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1079 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1080 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1081 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1082 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1083 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1084 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1085 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1086 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1087 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1088 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1089 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1090 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1091 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1092 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1093 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1094 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1095 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1096 				      info->reg_mvfr0, boot->reg_mvfr0);
1097 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1098 				      info->reg_mvfr1, boot->reg_mvfr1);
1099 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1100 				      info->reg_mvfr2, boot->reg_mvfr2);
1101 
1102 	return taint;
1103 }
1104 
1105 /*
1106  * Update system wide CPU feature registers with the values from a
1107  * non-boot CPU. Also performs SANITY checks to make sure that there
1108  * aren't any insane variations from that of the boot CPU.
1109  */
1110 void update_cpu_features(int cpu,
1111 			 struct cpuinfo_arm64 *info,
1112 			 struct cpuinfo_arm64 *boot)
1113 {
1114 	int taint = 0;
1115 
1116 	/*
1117 	 * The kernel can handle differing I-cache policies, but otherwise
1118 	 * caches should look identical. Userspace JITs will make use of
1119 	 * *minLine.
1120 	 */
1121 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1122 				      info->reg_ctr, boot->reg_ctr);
1123 
1124 	/*
1125 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1126 	 * could result in too much or too little memory being zeroed if a
1127 	 * process is preempted and migrated between CPUs.
1128 	 */
1129 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1130 				      info->reg_dczid, boot->reg_dczid);
1131 
1132 	/* If different, timekeeping will be broken (especially with KVM) */
1133 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1134 				      info->reg_cntfrq, boot->reg_cntfrq);
1135 
1136 	/*
1137 	 * The kernel uses self-hosted debug features and expects CPUs to
1138 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1139 	 * and BRPs to be identical.
1140 	 * ID_AA64DFR1 is currently RES0.
1141 	 */
1142 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1143 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1144 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1145 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1146 	/*
1147 	 * Even in big.LITTLE, processors should be identical instruction-set
1148 	 * wise.
1149 	 */
1150 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1151 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1152 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1153 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1154 
1155 	/*
1156 	 * Differing PARange support is fine as long as all peripherals and
1157 	 * memory are mapped within the minimum PARange of all CPUs.
1158 	 * Linux should not care about secure memory.
1159 	 */
1160 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1161 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1162 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1163 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1164 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1165 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1166 
1167 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1168 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1169 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1170 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1171 
1172 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1173 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1174 
1175 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1176 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1177 					info->reg_zcr, boot->reg_zcr);
1178 
1179 		/* Probe vector lengths, unless we already gave up on SVE */
1180 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1181 		    !system_capabilities_finalized())
1182 			vec_update_vq_map(ARM64_VEC_SVE);
1183 	}
1184 
1185 	/*
1186 	 * The kernel uses the LDGM/STGM instructions and the number of tags
1187 	 * they read/write depends on the GMID_EL1.BS field. Check that the
1188 	 * value is the same on all CPUs.
1189 	 */
1190 	if (IS_ENABLED(CONFIG_ARM64_MTE) &&
1191 	    id_aa64pfr1_mte(info->reg_id_aa64pfr1)) {
1192 		taint |= check_update_ftr_reg(SYS_GMID_EL1, cpu,
1193 					      info->reg_gmid, boot->reg_gmid);
1194 	}
1195 
1196 	/*
1197 	 * If we don't have AArch32 at all then skip the checks entirely
1198 	 * as the register values may be UNKNOWN and we're not going to be
1199 	 * using them for anything.
1200 	 *
1201 	 * This relies on a sanitised view of the AArch64 ID registers
1202 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1203 	 */
1204 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1205 		lazy_init_32bit_cpu_features(info, boot);
1206 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1207 						   &boot->aarch32);
1208 	}
1209 
1210 	/*
1211 	 * Mismatched CPU features are a recipe for disaster. Don't even
1212 	 * pretend to support them.
1213 	 */
1214 	if (taint) {
1215 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1216 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1217 	}
1218 }
1219 
1220 u64 read_sanitised_ftr_reg(u32 id)
1221 {
1222 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1223 
1224 	if (!regp)
1225 		return 0;
1226 	return regp->sys_val;
1227 }
1228 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1229 
1230 #define read_sysreg_case(r)	\
1231 	case r:		val = read_sysreg_s(r); break;
1232 
1233 /*
1234  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1235  * Read the system register on the current CPU
1236  */
1237 u64 __read_sysreg_by_encoding(u32 sys_id)
1238 {
1239 	struct arm64_ftr_reg *regp;
1240 	u64 val;
1241 
1242 	switch (sys_id) {
1243 	read_sysreg_case(SYS_ID_PFR0_EL1);
1244 	read_sysreg_case(SYS_ID_PFR1_EL1);
1245 	read_sysreg_case(SYS_ID_PFR2_EL1);
1246 	read_sysreg_case(SYS_ID_DFR0_EL1);
1247 	read_sysreg_case(SYS_ID_DFR1_EL1);
1248 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1249 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1250 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1251 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1252 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1253 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1254 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1255 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1256 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1257 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1258 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1259 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1260 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1261 	read_sysreg_case(SYS_MVFR0_EL1);
1262 	read_sysreg_case(SYS_MVFR1_EL1);
1263 	read_sysreg_case(SYS_MVFR2_EL1);
1264 
1265 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1266 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1267 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1268 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1269 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1270 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1271 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1272 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1273 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1274 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1275 
1276 	read_sysreg_case(SYS_CNTFRQ_EL0);
1277 	read_sysreg_case(SYS_CTR_EL0);
1278 	read_sysreg_case(SYS_DCZID_EL0);
1279 
1280 	default:
1281 		BUG();
1282 		return 0;
1283 	}
1284 
1285 	regp  = get_arm64_ftr_reg(sys_id);
1286 	if (regp) {
1287 		val &= ~regp->override->mask;
1288 		val |= (regp->override->val & regp->override->mask);
1289 	}
1290 
1291 	return val;
1292 }
1293 
1294 #include <linux/irqchip/arm-gic-v3.h>
1295 
1296 static bool
1297 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1298 {
1299 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1300 
1301 	return val >= entry->min_field_value;
1302 }
1303 
1304 static bool
1305 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1306 {
1307 	u64 val;
1308 
1309 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1310 	if (scope == SCOPE_SYSTEM)
1311 		val = read_sanitised_ftr_reg(entry->sys_reg);
1312 	else
1313 		val = __read_sysreg_by_encoding(entry->sys_reg);
1314 
1315 	return feature_matches(val, entry);
1316 }
1317 
1318 const struct cpumask *system_32bit_el0_cpumask(void)
1319 {
1320 	if (!system_supports_32bit_el0())
1321 		return cpu_none_mask;
1322 
1323 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1324 		return cpu_32bit_el0_mask;
1325 
1326 	return cpu_possible_mask;
1327 }
1328 
1329 static int __init parse_32bit_el0_param(char *str)
1330 {
1331 	allow_mismatched_32bit_el0 = true;
1332 	return 0;
1333 }
1334 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1335 
1336 static ssize_t aarch32_el0_show(struct device *dev,
1337 				struct device_attribute *attr, char *buf)
1338 {
1339 	const struct cpumask *mask = system_32bit_el0_cpumask();
1340 
1341 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1342 }
1343 static const DEVICE_ATTR_RO(aarch32_el0);
1344 
1345 static int __init aarch32_el0_sysfs_init(void)
1346 {
1347 	if (!allow_mismatched_32bit_el0)
1348 		return 0;
1349 
1350 	return device_create_file(cpu_subsys.dev_root, &dev_attr_aarch32_el0);
1351 }
1352 device_initcall(aarch32_el0_sysfs_init);
1353 
1354 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1355 {
1356 	if (!has_cpuid_feature(entry, scope))
1357 		return allow_mismatched_32bit_el0;
1358 
1359 	if (scope == SCOPE_SYSTEM)
1360 		pr_info("detected: 32-bit EL0 Support\n");
1361 
1362 	return true;
1363 }
1364 
1365 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1366 {
1367 	bool has_sre;
1368 
1369 	if (!has_cpuid_feature(entry, scope))
1370 		return false;
1371 
1372 	has_sre = gic_enable_sre();
1373 	if (!has_sre)
1374 		pr_warn_once("%s present but disabled by higher exception level\n",
1375 			     entry->desc);
1376 
1377 	return has_sre;
1378 }
1379 
1380 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1381 {
1382 	u32 midr = read_cpuid_id();
1383 
1384 	/* Cavium ThunderX pass 1.x and 2.x */
1385 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1386 		MIDR_CPU_VAR_REV(0, 0),
1387 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1388 }
1389 
1390 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1391 {
1392 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1393 
1394 	return cpuid_feature_extract_signed_field(pfr0,
1395 					ID_AA64PFR0_FP_SHIFT) < 0;
1396 }
1397 
1398 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1399 			  int scope)
1400 {
1401 	u64 ctr;
1402 
1403 	if (scope == SCOPE_SYSTEM)
1404 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1405 	else
1406 		ctr = read_cpuid_effective_cachetype();
1407 
1408 	return ctr & BIT(CTR_IDC_SHIFT);
1409 }
1410 
1411 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1412 {
1413 	/*
1414 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1415 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1416 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1417 	 * value.
1418 	 */
1419 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1420 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1421 }
1422 
1423 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1424 			  int scope)
1425 {
1426 	u64 ctr;
1427 
1428 	if (scope == SCOPE_SYSTEM)
1429 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1430 	else
1431 		ctr = read_cpuid_cachetype();
1432 
1433 	return ctr & BIT(CTR_DIC_SHIFT);
1434 }
1435 
1436 static bool __maybe_unused
1437 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1438 {
1439 	/*
1440 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1441 	 * may share TLB entries with a CPU stuck in the crashed
1442 	 * kernel.
1443 	 */
1444 	if (is_kdump_kernel())
1445 		return false;
1446 
1447 	if (cpus_have_const_cap(ARM64_WORKAROUND_NVIDIA_CARMEL_CNP))
1448 		return false;
1449 
1450 	return has_cpuid_feature(entry, scope);
1451 }
1452 
1453 /*
1454  * This check is triggered during the early boot before the cpufeature
1455  * is initialised. Checking the status on the local CPU allows the boot
1456  * CPU to detect the need for non-global mappings and thus avoiding a
1457  * pagetable re-write after all the CPUs are booted. This check will be
1458  * anyway run on individual CPUs, allowing us to get the consistent
1459  * state once the SMP CPUs are up and thus make the switch to non-global
1460  * mappings if required.
1461  */
1462 bool kaslr_requires_kpti(void)
1463 {
1464 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1465 		return false;
1466 
1467 	/*
1468 	 * E0PD does a similar job to KPTI so can be used instead
1469 	 * where available.
1470 	 */
1471 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1472 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1473 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1474 						ID_AA64MMFR2_E0PD_SHIFT))
1475 			return false;
1476 	}
1477 
1478 	/*
1479 	 * Systems affected by Cavium erratum 24756 are incompatible
1480 	 * with KPTI.
1481 	 */
1482 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1483 		extern const struct midr_range cavium_erratum_27456_cpus[];
1484 
1485 		if (is_midr_in_range_list(read_cpuid_id(),
1486 					  cavium_erratum_27456_cpus))
1487 			return false;
1488 	}
1489 
1490 	return kaslr_offset() > 0;
1491 }
1492 
1493 static bool __meltdown_safe = true;
1494 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1495 
1496 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1497 				int scope)
1498 {
1499 	/* List of CPUs that are not vulnerable and don't need KPTI */
1500 	static const struct midr_range kpti_safe_list[] = {
1501 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1502 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1503 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1504 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1505 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1506 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1507 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1508 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1509 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1510 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1511 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1512 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1513 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1514 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1515 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1516 		{ /* sentinel */ }
1517 	};
1518 	char const *str = "kpti command line option";
1519 	bool meltdown_safe;
1520 
1521 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1522 
1523 	/* Defer to CPU feature registers */
1524 	if (has_cpuid_feature(entry, scope))
1525 		meltdown_safe = true;
1526 
1527 	if (!meltdown_safe)
1528 		__meltdown_safe = false;
1529 
1530 	/*
1531 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1532 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1533 	 * ends as well as you might imagine. Don't even try. We cannot rely
1534 	 * on the cpus_have_*cap() helpers here to detect the CPU erratum
1535 	 * because cpucap detection order may change. However, since we know
1536 	 * affected CPUs are always in a homogeneous configuration, it is
1537 	 * safe to rely on this_cpu_has_cap() here.
1538 	 */
1539 	if (this_cpu_has_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1540 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1541 		__kpti_forced = -1;
1542 	}
1543 
1544 	/* Useful for KASLR robustness */
1545 	if (kaslr_requires_kpti()) {
1546 		if (!__kpti_forced) {
1547 			str = "KASLR";
1548 			__kpti_forced = 1;
1549 		}
1550 	}
1551 
1552 	if (cpu_mitigations_off() && !__kpti_forced) {
1553 		str = "mitigations=off";
1554 		__kpti_forced = -1;
1555 	}
1556 
1557 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1558 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1559 		return false;
1560 	}
1561 
1562 	/* Forced? */
1563 	if (__kpti_forced) {
1564 		pr_info_once("kernel page table isolation forced %s by %s\n",
1565 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1566 		return __kpti_forced > 0;
1567 	}
1568 
1569 	return !meltdown_safe;
1570 }
1571 
1572 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1573 static void __nocfi
1574 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1575 {
1576 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1577 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1578 	kpti_remap_fn *remap_fn;
1579 
1580 	int cpu = smp_processor_id();
1581 
1582 	/*
1583 	 * We don't need to rewrite the page-tables if either we've done
1584 	 * it already or we have KASLR enabled and therefore have not
1585 	 * created any global mappings at all.
1586 	 */
1587 	if (arm64_use_ng_mappings)
1588 		return;
1589 
1590 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1591 
1592 	cpu_install_idmap();
1593 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1594 	cpu_uninstall_idmap();
1595 
1596 	if (!cpu)
1597 		arm64_use_ng_mappings = true;
1598 }
1599 #else
1600 static void
1601 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1602 {
1603 }
1604 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1605 
1606 static int __init parse_kpti(char *str)
1607 {
1608 	bool enabled;
1609 	int ret = strtobool(str, &enabled);
1610 
1611 	if (ret)
1612 		return ret;
1613 
1614 	__kpti_forced = enabled ? 1 : -1;
1615 	return 0;
1616 }
1617 early_param("kpti", parse_kpti);
1618 
1619 #ifdef CONFIG_ARM64_HW_AFDBM
1620 static inline void __cpu_enable_hw_dbm(void)
1621 {
1622 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1623 
1624 	write_sysreg(tcr, tcr_el1);
1625 	isb();
1626 	local_flush_tlb_all();
1627 }
1628 
1629 static bool cpu_has_broken_dbm(void)
1630 {
1631 	/* List of CPUs which have broken DBM support. */
1632 	static const struct midr_range cpus[] = {
1633 #ifdef CONFIG_ARM64_ERRATUM_1024718
1634 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1635 		/* Kryo4xx Silver (rdpe => r1p0) */
1636 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1637 #endif
1638 		{},
1639 	};
1640 
1641 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1642 }
1643 
1644 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1645 {
1646 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1647 	       !cpu_has_broken_dbm();
1648 }
1649 
1650 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1651 {
1652 	if (cpu_can_use_dbm(cap))
1653 		__cpu_enable_hw_dbm();
1654 }
1655 
1656 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1657 		       int __unused)
1658 {
1659 	static bool detected = false;
1660 	/*
1661 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1662 	 * run a mix of CPUs with and without the feature. So, we
1663 	 * unconditionally enable the capability to allow any late CPU
1664 	 * to use the feature. We only enable the control bits on the
1665 	 * CPU, if it actually supports.
1666 	 *
1667 	 * We have to make sure we print the "feature" detection only
1668 	 * when at least one CPU actually uses it. So check if this CPU
1669 	 * can actually use it and print the message exactly once.
1670 	 *
1671 	 * This is safe as all CPUs (including secondary CPUs - due to the
1672 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1673 	 * goes through the "matches" check exactly once. Also if a CPU
1674 	 * matches the criteria, it is guaranteed that the CPU will turn
1675 	 * the DBM on, as the capability is unconditionally enabled.
1676 	 */
1677 	if (!detected && cpu_can_use_dbm(cap)) {
1678 		detected = true;
1679 		pr_info("detected: Hardware dirty bit management\n");
1680 	}
1681 
1682 	return true;
1683 }
1684 
1685 #endif
1686 
1687 #ifdef CONFIG_ARM64_AMU_EXTN
1688 
1689 /*
1690  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1691  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1692  * information regarding all the events that it supports. When a CPU bit is
1693  * set in the cpumask, the user of this feature can only rely on the presence
1694  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1695  * counters are enabled or access to these counters is enabled by code
1696  * executed at higher exception levels (firmware).
1697  */
1698 static struct cpumask amu_cpus __read_mostly;
1699 
1700 bool cpu_has_amu_feat(int cpu)
1701 {
1702 	return cpumask_test_cpu(cpu, &amu_cpus);
1703 }
1704 
1705 int get_cpu_with_amu_feat(void)
1706 {
1707 	return cpumask_any(&amu_cpus);
1708 }
1709 
1710 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1711 {
1712 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1713 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1714 			smp_processor_id());
1715 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1716 		update_freq_counters_refs();
1717 	}
1718 }
1719 
1720 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1721 		    int __unused)
1722 {
1723 	/*
1724 	 * The AMU extension is a non-conflicting feature: the kernel can
1725 	 * safely run a mix of CPUs with and without support for the
1726 	 * activity monitors extension. Therefore, unconditionally enable
1727 	 * the capability to allow any late CPU to use the feature.
1728 	 *
1729 	 * With this feature unconditionally enabled, the cpu_enable
1730 	 * function will be called for all CPUs that match the criteria,
1731 	 * including secondary and hotplugged, marking this feature as
1732 	 * present on that respective CPU. The enable function will also
1733 	 * print a detection message.
1734 	 */
1735 
1736 	return true;
1737 }
1738 #else
1739 int get_cpu_with_amu_feat(void)
1740 {
1741 	return nr_cpu_ids;
1742 }
1743 #endif
1744 
1745 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1746 {
1747 	return is_kernel_in_hyp_mode();
1748 }
1749 
1750 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1751 {
1752 	/*
1753 	 * Copy register values that aren't redirected by hardware.
1754 	 *
1755 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1756 	 * this value to tpidr_el2 before we patch the code. Once we've done
1757 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1758 	 * do anything here.
1759 	 */
1760 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1761 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1762 }
1763 
1764 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1765 {
1766 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1767 
1768 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1769 	WARN_ON(CLIDR_LOUU(val) || CLIDR_LOUIS(val));
1770 }
1771 
1772 #ifdef CONFIG_ARM64_PAN
1773 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1774 {
1775 	/*
1776 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1777 	 * is discarded once we return from the exception.
1778 	 */
1779 	WARN_ON_ONCE(in_interrupt());
1780 
1781 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1782 	set_pstate_pan(1);
1783 }
1784 #endif /* CONFIG_ARM64_PAN */
1785 
1786 #ifdef CONFIG_ARM64_RAS_EXTN
1787 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1788 {
1789 	/* Firmware may have left a deferred SError in this register. */
1790 	write_sysreg_s(0, SYS_DISR_EL1);
1791 }
1792 #endif /* CONFIG_ARM64_RAS_EXTN */
1793 
1794 #ifdef CONFIG_ARM64_PTR_AUTH
1795 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1796 {
1797 	int boot_val, sec_val;
1798 
1799 	/* We don't expect to be called with SCOPE_SYSTEM */
1800 	WARN_ON(scope == SCOPE_SYSTEM);
1801 	/*
1802 	 * The ptr-auth feature levels are not intercompatible with lower
1803 	 * levels. Hence we must match ptr-auth feature level of the secondary
1804 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1805 	 * from the sanitised register whereas direct register read is done for
1806 	 * the secondary CPUs.
1807 	 * The sanitised feature state is guaranteed to match that of the
1808 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1809 	 * a chance to update the state, with the capability.
1810 	 */
1811 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1812 					       entry->field_pos, entry->sign);
1813 	if (scope & SCOPE_BOOT_CPU)
1814 		return boot_val >= entry->min_field_value;
1815 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1816 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1817 					      entry->field_pos, entry->sign);
1818 	return sec_val == boot_val;
1819 }
1820 
1821 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1822 				     int scope)
1823 {
1824 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1825 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1826 }
1827 
1828 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1829 			     int __unused)
1830 {
1831 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1832 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1833 }
1834 #endif /* CONFIG_ARM64_PTR_AUTH */
1835 
1836 #ifdef CONFIG_ARM64_E0PD
1837 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1838 {
1839 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1840 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1841 }
1842 #endif /* CONFIG_ARM64_E0PD */
1843 
1844 #ifdef CONFIG_ARM64_PSEUDO_NMI
1845 static bool enable_pseudo_nmi;
1846 
1847 static int __init early_enable_pseudo_nmi(char *p)
1848 {
1849 	return strtobool(p, &enable_pseudo_nmi);
1850 }
1851 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1852 
1853 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1854 				   int scope)
1855 {
1856 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1857 }
1858 #endif
1859 
1860 #ifdef CONFIG_ARM64_BTI
1861 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1862 {
1863 	/*
1864 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1865 	 * function entry points using BR is a requirement for
1866 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1867 	 * So, be strict and forbid other BRs using other registers to
1868 	 * jump onto a PACIxSP instruction:
1869 	 */
1870 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1871 	isb();
1872 }
1873 #endif /* CONFIG_ARM64_BTI */
1874 
1875 #ifdef CONFIG_ARM64_MTE
1876 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1877 {
1878 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
1879 	isb();
1880 
1881 	/*
1882 	 * Clear the tags in the zero page. This needs to be done via the
1883 	 * linear map which has the Tagged attribute.
1884 	 */
1885 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1886 		mte_clear_page_tags(lm_alias(empty_zero_page));
1887 
1888 	kasan_init_hw_tags_cpu();
1889 }
1890 #endif /* CONFIG_ARM64_MTE */
1891 
1892 #ifdef CONFIG_KVM
1893 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1894 {
1895 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1896 		return false;
1897 
1898 	if (is_kernel_in_hyp_mode()) {
1899 		pr_warn("Protected KVM not available with VHE\n");
1900 		return false;
1901 	}
1902 
1903 	return true;
1904 }
1905 #endif /* CONFIG_KVM */
1906 
1907 /* Internal helper functions to match cpu capability type */
1908 static bool
1909 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1910 {
1911 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1912 }
1913 
1914 static bool
1915 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1916 {
1917 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1918 }
1919 
1920 static bool
1921 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1922 {
1923 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1924 }
1925 
1926 static const struct arm64_cpu_capabilities arm64_features[] = {
1927 	{
1928 		.desc = "GIC system register CPU interface",
1929 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1930 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1931 		.matches = has_useable_gicv3_cpuif,
1932 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1933 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1934 		.sign = FTR_UNSIGNED,
1935 		.min_field_value = 1,
1936 	},
1937 	{
1938 		.desc = "Enhanced Counter Virtualization",
1939 		.capability = ARM64_HAS_ECV,
1940 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1941 		.matches = has_cpuid_feature,
1942 		.sys_reg = SYS_ID_AA64MMFR0_EL1,
1943 		.field_pos = ID_AA64MMFR0_ECV_SHIFT,
1944 		.sign = FTR_UNSIGNED,
1945 		.min_field_value = 1,
1946 	},
1947 #ifdef CONFIG_ARM64_PAN
1948 	{
1949 		.desc = "Privileged Access Never",
1950 		.capability = ARM64_HAS_PAN,
1951 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1952 		.matches = has_cpuid_feature,
1953 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1954 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1955 		.sign = FTR_UNSIGNED,
1956 		.min_field_value = 1,
1957 		.cpu_enable = cpu_enable_pan,
1958 	},
1959 #endif /* CONFIG_ARM64_PAN */
1960 #ifdef CONFIG_ARM64_EPAN
1961 	{
1962 		.desc = "Enhanced Privileged Access Never",
1963 		.capability = ARM64_HAS_EPAN,
1964 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1965 		.matches = has_cpuid_feature,
1966 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1967 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1968 		.sign = FTR_UNSIGNED,
1969 		.min_field_value = 3,
1970 	},
1971 #endif /* CONFIG_ARM64_EPAN */
1972 #ifdef CONFIG_ARM64_LSE_ATOMICS
1973 	{
1974 		.desc = "LSE atomic instructions",
1975 		.capability = ARM64_HAS_LSE_ATOMICS,
1976 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1977 		.matches = has_cpuid_feature,
1978 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1979 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1980 		.sign = FTR_UNSIGNED,
1981 		.min_field_value = 2,
1982 	},
1983 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1984 	{
1985 		.desc = "Software prefetching using PRFM",
1986 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1987 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1988 		.matches = has_no_hw_prefetch,
1989 	},
1990 	{
1991 		.desc = "Virtualization Host Extensions",
1992 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1993 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1994 		.matches = runs_at_el2,
1995 		.cpu_enable = cpu_copy_el2regs,
1996 	},
1997 	{
1998 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
1999 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2000 		.matches = has_32bit_el0,
2001 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2002 		.sign = FTR_UNSIGNED,
2003 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
2004 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2005 	},
2006 #ifdef CONFIG_KVM
2007 	{
2008 		.desc = "32-bit EL1 Support",
2009 		.capability = ARM64_HAS_32BIT_EL1,
2010 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2011 		.matches = has_cpuid_feature,
2012 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2013 		.sign = FTR_UNSIGNED,
2014 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
2015 		.min_field_value = ID_AA64PFR0_ELx_32BIT_64BIT,
2016 	},
2017 	{
2018 		.desc = "Protected KVM",
2019 		.capability = ARM64_KVM_PROTECTED_MODE,
2020 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2021 		.matches = is_kvm_protected_mode,
2022 	},
2023 #endif
2024 	{
2025 		.desc = "Kernel page table isolation (KPTI)",
2026 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2027 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2028 		/*
2029 		 * The ID feature fields below are used to indicate that
2030 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2031 		 * more details.
2032 		 */
2033 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2034 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
2035 		.min_field_value = 1,
2036 		.matches = unmap_kernel_at_el0,
2037 		.cpu_enable = kpti_install_ng_mappings,
2038 	},
2039 	{
2040 		/* FP/SIMD is not implemented */
2041 		.capability = ARM64_HAS_NO_FPSIMD,
2042 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2043 		.min_field_value = 0,
2044 		.matches = has_no_fpsimd,
2045 	},
2046 #ifdef CONFIG_ARM64_PMEM
2047 	{
2048 		.desc = "Data cache clean to Point of Persistence",
2049 		.capability = ARM64_HAS_DCPOP,
2050 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2051 		.matches = has_cpuid_feature,
2052 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2053 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2054 		.min_field_value = 1,
2055 	},
2056 	{
2057 		.desc = "Data cache clean to Point of Deep Persistence",
2058 		.capability = ARM64_HAS_DCPODP,
2059 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2060 		.matches = has_cpuid_feature,
2061 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2062 		.sign = FTR_UNSIGNED,
2063 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2064 		.min_field_value = 2,
2065 	},
2066 #endif
2067 #ifdef CONFIG_ARM64_SVE
2068 	{
2069 		.desc = "Scalable Vector Extension",
2070 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2071 		.capability = ARM64_SVE,
2072 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2073 		.sign = FTR_UNSIGNED,
2074 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2075 		.min_field_value = ID_AA64PFR0_SVE,
2076 		.matches = has_cpuid_feature,
2077 		.cpu_enable = sve_kernel_enable,
2078 	},
2079 #endif /* CONFIG_ARM64_SVE */
2080 #ifdef CONFIG_ARM64_RAS_EXTN
2081 	{
2082 		.desc = "RAS Extension Support",
2083 		.capability = ARM64_HAS_RAS_EXTN,
2084 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2085 		.matches = has_cpuid_feature,
2086 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2087 		.sign = FTR_UNSIGNED,
2088 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2089 		.min_field_value = ID_AA64PFR0_RAS_V1,
2090 		.cpu_enable = cpu_clear_disr,
2091 	},
2092 #endif /* CONFIG_ARM64_RAS_EXTN */
2093 #ifdef CONFIG_ARM64_AMU_EXTN
2094 	{
2095 		/*
2096 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2097 		 * Therefore, don't provide .desc as we don't want the detection
2098 		 * message to be shown until at least one CPU is detected to
2099 		 * support the feature.
2100 		 */
2101 		.capability = ARM64_HAS_AMU_EXTN,
2102 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2103 		.matches = has_amu,
2104 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2105 		.sign = FTR_UNSIGNED,
2106 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2107 		.min_field_value = ID_AA64PFR0_AMU,
2108 		.cpu_enable = cpu_amu_enable,
2109 	},
2110 #endif /* CONFIG_ARM64_AMU_EXTN */
2111 	{
2112 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2113 		.capability = ARM64_HAS_CACHE_IDC,
2114 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2115 		.matches = has_cache_idc,
2116 		.cpu_enable = cpu_emulate_effective_ctr,
2117 	},
2118 	{
2119 		.desc = "Instruction cache invalidation not required for I/D coherence",
2120 		.capability = ARM64_HAS_CACHE_DIC,
2121 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2122 		.matches = has_cache_dic,
2123 	},
2124 	{
2125 		.desc = "Stage-2 Force Write-Back",
2126 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2127 		.capability = ARM64_HAS_STAGE2_FWB,
2128 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2129 		.sign = FTR_UNSIGNED,
2130 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2131 		.min_field_value = 1,
2132 		.matches = has_cpuid_feature,
2133 		.cpu_enable = cpu_has_fwb,
2134 	},
2135 	{
2136 		.desc = "ARMv8.4 Translation Table Level",
2137 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2138 		.capability = ARM64_HAS_ARMv8_4_TTL,
2139 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2140 		.sign = FTR_UNSIGNED,
2141 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2142 		.min_field_value = 1,
2143 		.matches = has_cpuid_feature,
2144 	},
2145 	{
2146 		.desc = "TLB range maintenance instructions",
2147 		.capability = ARM64_HAS_TLB_RANGE,
2148 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2149 		.matches = has_cpuid_feature,
2150 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2151 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
2152 		.sign = FTR_UNSIGNED,
2153 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
2154 	},
2155 #ifdef CONFIG_ARM64_HW_AFDBM
2156 	{
2157 		/*
2158 		 * Since we turn this on always, we don't want the user to
2159 		 * think that the feature is available when it may not be.
2160 		 * So hide the description.
2161 		 *
2162 		 * .desc = "Hardware pagetable Dirty Bit Management",
2163 		 *
2164 		 */
2165 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2166 		.capability = ARM64_HW_DBM,
2167 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2168 		.sign = FTR_UNSIGNED,
2169 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2170 		.min_field_value = 2,
2171 		.matches = has_hw_dbm,
2172 		.cpu_enable = cpu_enable_hw_dbm,
2173 	},
2174 #endif
2175 	{
2176 		.desc = "CRC32 instructions",
2177 		.capability = ARM64_HAS_CRC32,
2178 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2179 		.matches = has_cpuid_feature,
2180 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2181 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2182 		.min_field_value = 1,
2183 	},
2184 	{
2185 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2186 		.capability = ARM64_SSBS,
2187 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2188 		.matches = has_cpuid_feature,
2189 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2190 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2191 		.sign = FTR_UNSIGNED,
2192 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2193 	},
2194 #ifdef CONFIG_ARM64_CNP
2195 	{
2196 		.desc = "Common not Private translations",
2197 		.capability = ARM64_HAS_CNP,
2198 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2199 		.matches = has_useable_cnp,
2200 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2201 		.sign = FTR_UNSIGNED,
2202 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2203 		.min_field_value = 1,
2204 		.cpu_enable = cpu_enable_cnp,
2205 	},
2206 #endif
2207 	{
2208 		.desc = "Speculation barrier (SB)",
2209 		.capability = ARM64_HAS_SB,
2210 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2211 		.matches = has_cpuid_feature,
2212 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2213 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2214 		.sign = FTR_UNSIGNED,
2215 		.min_field_value = 1,
2216 	},
2217 #ifdef CONFIG_ARM64_PTR_AUTH
2218 	{
2219 		.desc = "Address authentication (architected algorithm)",
2220 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2221 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2222 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2223 		.sign = FTR_UNSIGNED,
2224 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2225 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2226 		.matches = has_address_auth_cpucap,
2227 	},
2228 	{
2229 		.desc = "Address authentication (IMP DEF algorithm)",
2230 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2231 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2232 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2233 		.sign = FTR_UNSIGNED,
2234 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2235 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2236 		.matches = has_address_auth_cpucap,
2237 	},
2238 	{
2239 		.capability = ARM64_HAS_ADDRESS_AUTH,
2240 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2241 		.matches = has_address_auth_metacap,
2242 	},
2243 	{
2244 		.desc = "Generic authentication (architected algorithm)",
2245 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2246 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2247 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2248 		.sign = FTR_UNSIGNED,
2249 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2250 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2251 		.matches = has_cpuid_feature,
2252 	},
2253 	{
2254 		.desc = "Generic authentication (IMP DEF algorithm)",
2255 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2256 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2257 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2258 		.sign = FTR_UNSIGNED,
2259 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2260 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2261 		.matches = has_cpuid_feature,
2262 	},
2263 	{
2264 		.capability = ARM64_HAS_GENERIC_AUTH,
2265 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2266 		.matches = has_generic_auth,
2267 	},
2268 #endif /* CONFIG_ARM64_PTR_AUTH */
2269 #ifdef CONFIG_ARM64_PSEUDO_NMI
2270 	{
2271 		/*
2272 		 * Depends on having GICv3
2273 		 */
2274 		.desc = "IRQ priority masking",
2275 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2276 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2277 		.matches = can_use_gic_priorities,
2278 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2279 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2280 		.sign = FTR_UNSIGNED,
2281 		.min_field_value = 1,
2282 	},
2283 #endif
2284 #ifdef CONFIG_ARM64_E0PD
2285 	{
2286 		.desc = "E0PD",
2287 		.capability = ARM64_HAS_E0PD,
2288 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2289 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2290 		.sign = FTR_UNSIGNED,
2291 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2292 		.matches = has_cpuid_feature,
2293 		.min_field_value = 1,
2294 		.cpu_enable = cpu_enable_e0pd,
2295 	},
2296 #endif
2297 #ifdef CONFIG_ARCH_RANDOM
2298 	{
2299 		.desc = "Random Number Generator",
2300 		.capability = ARM64_HAS_RNG,
2301 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2302 		.matches = has_cpuid_feature,
2303 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2304 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2305 		.sign = FTR_UNSIGNED,
2306 		.min_field_value = 1,
2307 	},
2308 #endif
2309 #ifdef CONFIG_ARM64_BTI
2310 	{
2311 		.desc = "Branch Target Identification",
2312 		.capability = ARM64_BTI,
2313 #ifdef CONFIG_ARM64_BTI_KERNEL
2314 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2315 #else
2316 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2317 #endif
2318 		.matches = has_cpuid_feature,
2319 		.cpu_enable = bti_enable,
2320 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2321 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2322 		.min_field_value = ID_AA64PFR1_BT_BTI,
2323 		.sign = FTR_UNSIGNED,
2324 	},
2325 #endif
2326 #ifdef CONFIG_ARM64_MTE
2327 	{
2328 		.desc = "Memory Tagging Extension",
2329 		.capability = ARM64_MTE,
2330 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2331 		.matches = has_cpuid_feature,
2332 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2333 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2334 		.min_field_value = ID_AA64PFR1_MTE,
2335 		.sign = FTR_UNSIGNED,
2336 		.cpu_enable = cpu_enable_mte,
2337 	},
2338 	{
2339 		.desc = "Asymmetric MTE Tag Check Fault",
2340 		.capability = ARM64_MTE_ASYMM,
2341 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2342 		.matches = has_cpuid_feature,
2343 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2344 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2345 		.min_field_value = ID_AA64PFR1_MTE_ASYMM,
2346 		.sign = FTR_UNSIGNED,
2347 	},
2348 #endif /* CONFIG_ARM64_MTE */
2349 	{
2350 		.desc = "RCpc load-acquire (LDAPR)",
2351 		.capability = ARM64_HAS_LDAPR,
2352 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2353 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2354 		.sign = FTR_UNSIGNED,
2355 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2356 		.matches = has_cpuid_feature,
2357 		.min_field_value = 1,
2358 	},
2359 	{},
2360 };
2361 
2362 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2363 		.matches = has_cpuid_feature,					\
2364 		.sys_reg = reg,							\
2365 		.field_pos = field,						\
2366 		.sign = s,							\
2367 		.min_field_value = min_value,
2368 
2369 #define __HWCAP_CAP(name, cap_type, cap)					\
2370 		.desc = name,							\
2371 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2372 		.hwcap_type = cap_type,						\
2373 		.hwcap = cap,							\
2374 
2375 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2376 	{									\
2377 		__HWCAP_CAP(#cap, cap_type, cap)				\
2378 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2379 	}
2380 
2381 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2382 	{									\
2383 		__HWCAP_CAP(#cap, cap_type, cap)				\
2384 		.matches = cpucap_multi_entry_cap_matches,			\
2385 		.match_list = list,						\
2386 	}
2387 
2388 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2389 	{									\
2390 		__HWCAP_CAP(#cap, cap_type, cap)				\
2391 		.matches = match,						\
2392 	}
2393 
2394 #ifdef CONFIG_ARM64_PTR_AUTH
2395 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2396 	{
2397 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2398 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2399 	},
2400 	{
2401 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2402 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2403 	},
2404 	{},
2405 };
2406 
2407 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2408 	{
2409 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2410 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2411 	},
2412 	{
2413 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2414 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2415 	},
2416 	{},
2417 };
2418 #endif
2419 
2420 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2421 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2422 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2423 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2424 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2425 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2426 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2427 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2428 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2429 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2430 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2431 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2432 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2433 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2434 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2435 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2436 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2437 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2438 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2439 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2440 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2441 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2442 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2443 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2444 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2445 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2446 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2447 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2448 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2449 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2450 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2451 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2452 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2453 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2454 #ifdef CONFIG_ARM64_SVE
2455 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2456 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2457 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2458 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2459 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2460 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2461 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2462 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2463 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2464 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2465 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2466 #endif
2467 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2468 #ifdef CONFIG_ARM64_BTI
2469 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2470 #endif
2471 #ifdef CONFIG_ARM64_PTR_AUTH
2472 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2473 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2474 #endif
2475 #ifdef CONFIG_ARM64_MTE
2476 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2477 #endif /* CONFIG_ARM64_MTE */
2478 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2479 	{},
2480 };
2481 
2482 #ifdef CONFIG_COMPAT
2483 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2484 {
2485 	/*
2486 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2487 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2488 	 * check is future proof, by making sure value is non-zero.
2489 	 */
2490 	u32 mvfr1;
2491 
2492 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2493 	if (scope == SCOPE_SYSTEM)
2494 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2495 	else
2496 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2497 
2498 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2499 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2500 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2501 }
2502 #endif
2503 
2504 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2505 #ifdef CONFIG_COMPAT
2506 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2507 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2508 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2509 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2510 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2511 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2512 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2513 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2514 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2515 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2516 #endif
2517 	{},
2518 };
2519 
2520 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2521 {
2522 	switch (cap->hwcap_type) {
2523 	case CAP_HWCAP:
2524 		cpu_set_feature(cap->hwcap);
2525 		break;
2526 #ifdef CONFIG_COMPAT
2527 	case CAP_COMPAT_HWCAP:
2528 		compat_elf_hwcap |= (u32)cap->hwcap;
2529 		break;
2530 	case CAP_COMPAT_HWCAP2:
2531 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2532 		break;
2533 #endif
2534 	default:
2535 		WARN_ON(1);
2536 		break;
2537 	}
2538 }
2539 
2540 /* Check if we have a particular HWCAP enabled */
2541 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2542 {
2543 	bool rc;
2544 
2545 	switch (cap->hwcap_type) {
2546 	case CAP_HWCAP:
2547 		rc = cpu_have_feature(cap->hwcap);
2548 		break;
2549 #ifdef CONFIG_COMPAT
2550 	case CAP_COMPAT_HWCAP:
2551 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2552 		break;
2553 	case CAP_COMPAT_HWCAP2:
2554 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2555 		break;
2556 #endif
2557 	default:
2558 		WARN_ON(1);
2559 		rc = false;
2560 	}
2561 
2562 	return rc;
2563 }
2564 
2565 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2566 {
2567 	/* We support emulation of accesses to CPU ID feature registers */
2568 	cpu_set_named_feature(CPUID);
2569 	for (; hwcaps->matches; hwcaps++)
2570 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2571 			cap_set_elf_hwcap(hwcaps);
2572 }
2573 
2574 static void update_cpu_capabilities(u16 scope_mask)
2575 {
2576 	int i;
2577 	const struct arm64_cpu_capabilities *caps;
2578 
2579 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2580 	for (i = 0; i < ARM64_NCAPS; i++) {
2581 		caps = cpu_hwcaps_ptrs[i];
2582 		if (!caps || !(caps->type & scope_mask) ||
2583 		    cpus_have_cap(caps->capability) ||
2584 		    !caps->matches(caps, cpucap_default_scope(caps)))
2585 			continue;
2586 
2587 		if (caps->desc)
2588 			pr_info("detected: %s\n", caps->desc);
2589 		cpus_set_cap(caps->capability);
2590 
2591 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2592 			set_bit(caps->capability, boot_capabilities);
2593 	}
2594 }
2595 
2596 /*
2597  * Enable all the available capabilities on this CPU. The capabilities
2598  * with BOOT_CPU scope are handled separately and hence skipped here.
2599  */
2600 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2601 {
2602 	int i;
2603 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2604 
2605 	for_each_available_cap(i) {
2606 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2607 
2608 		if (WARN_ON(!cap))
2609 			continue;
2610 
2611 		if (!(cap->type & non_boot_scope))
2612 			continue;
2613 
2614 		if (cap->cpu_enable)
2615 			cap->cpu_enable(cap);
2616 	}
2617 	return 0;
2618 }
2619 
2620 /*
2621  * Run through the enabled capabilities and enable() it on all active
2622  * CPUs
2623  */
2624 static void __init enable_cpu_capabilities(u16 scope_mask)
2625 {
2626 	int i;
2627 	const struct arm64_cpu_capabilities *caps;
2628 	bool boot_scope;
2629 
2630 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2631 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2632 
2633 	for (i = 0; i < ARM64_NCAPS; i++) {
2634 		unsigned int num;
2635 
2636 		caps = cpu_hwcaps_ptrs[i];
2637 		if (!caps || !(caps->type & scope_mask))
2638 			continue;
2639 		num = caps->capability;
2640 		if (!cpus_have_cap(num))
2641 			continue;
2642 
2643 		/* Ensure cpus_have_const_cap(num) works */
2644 		static_branch_enable(&cpu_hwcap_keys[num]);
2645 
2646 		if (boot_scope && caps->cpu_enable)
2647 			/*
2648 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2649 			 * before any secondary CPU boots. Thus, each secondary
2650 			 * will enable the capability as appropriate via
2651 			 * check_local_cpu_capabilities(). The only exception is
2652 			 * the boot CPU, for which the capability must be
2653 			 * enabled here. This approach avoids costly
2654 			 * stop_machine() calls for this case.
2655 			 */
2656 			caps->cpu_enable(caps);
2657 	}
2658 
2659 	/*
2660 	 * For all non-boot scope capabilities, use stop_machine()
2661 	 * as it schedules the work allowing us to modify PSTATE,
2662 	 * instead of on_each_cpu() which uses an IPI, giving us a
2663 	 * PSTATE that disappears when we return.
2664 	 */
2665 	if (!boot_scope)
2666 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2667 			     NULL, cpu_online_mask);
2668 }
2669 
2670 /*
2671  * Run through the list of capabilities to check for conflicts.
2672  * If the system has already detected a capability, take necessary
2673  * action on this CPU.
2674  */
2675 static void verify_local_cpu_caps(u16 scope_mask)
2676 {
2677 	int i;
2678 	bool cpu_has_cap, system_has_cap;
2679 	const struct arm64_cpu_capabilities *caps;
2680 
2681 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2682 
2683 	for (i = 0; i < ARM64_NCAPS; i++) {
2684 		caps = cpu_hwcaps_ptrs[i];
2685 		if (!caps || !(caps->type & scope_mask))
2686 			continue;
2687 
2688 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2689 		system_has_cap = cpus_have_cap(caps->capability);
2690 
2691 		if (system_has_cap) {
2692 			/*
2693 			 * Check if the new CPU misses an advertised feature,
2694 			 * which is not safe to miss.
2695 			 */
2696 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2697 				break;
2698 			/*
2699 			 * We have to issue cpu_enable() irrespective of
2700 			 * whether the CPU has it or not, as it is enabeld
2701 			 * system wide. It is upto the call back to take
2702 			 * appropriate action on this CPU.
2703 			 */
2704 			if (caps->cpu_enable)
2705 				caps->cpu_enable(caps);
2706 		} else {
2707 			/*
2708 			 * Check if the CPU has this capability if it isn't
2709 			 * safe to have when the system doesn't.
2710 			 */
2711 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2712 				break;
2713 		}
2714 	}
2715 
2716 	if (i < ARM64_NCAPS) {
2717 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2718 			smp_processor_id(), caps->capability,
2719 			caps->desc, system_has_cap, cpu_has_cap);
2720 
2721 		if (cpucap_panic_on_conflict(caps))
2722 			cpu_panic_kernel();
2723 		else
2724 			cpu_die_early();
2725 	}
2726 }
2727 
2728 /*
2729  * Check for CPU features that are used in early boot
2730  * based on the Boot CPU value.
2731  */
2732 static void check_early_cpu_features(void)
2733 {
2734 	verify_cpu_asid_bits();
2735 
2736 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2737 }
2738 
2739 static void
2740 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2741 {
2742 
2743 	for (; caps->matches; caps++)
2744 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2745 			pr_crit("CPU%d: missing HWCAP: %s\n",
2746 					smp_processor_id(), caps->desc);
2747 			cpu_die_early();
2748 		}
2749 }
2750 
2751 static void verify_local_elf_hwcaps(void)
2752 {
2753 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2754 
2755 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2756 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2757 }
2758 
2759 static void verify_sve_features(void)
2760 {
2761 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2762 	u64 zcr = read_zcr_features();
2763 
2764 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2765 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2766 
2767 	if (len < safe_len || vec_verify_vq_map(ARM64_VEC_SVE)) {
2768 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2769 			smp_processor_id());
2770 		cpu_die_early();
2771 	}
2772 
2773 	/* Add checks on other ZCR bits here if necessary */
2774 }
2775 
2776 static void verify_hyp_capabilities(void)
2777 {
2778 	u64 safe_mmfr1, mmfr0, mmfr1;
2779 	int parange, ipa_max;
2780 	unsigned int safe_vmid_bits, vmid_bits;
2781 
2782 	if (!IS_ENABLED(CONFIG_KVM))
2783 		return;
2784 
2785 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2786 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2787 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2788 
2789 	/* Verify VMID bits */
2790 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2791 	vmid_bits = get_vmid_bits(mmfr1);
2792 	if (vmid_bits < safe_vmid_bits) {
2793 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2794 		cpu_die_early();
2795 	}
2796 
2797 	/* Verify IPA range */
2798 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2799 				ID_AA64MMFR0_PARANGE_SHIFT);
2800 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2801 	if (ipa_max < get_kvm_ipa_limit()) {
2802 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2803 		cpu_die_early();
2804 	}
2805 }
2806 
2807 /*
2808  * Run through the enabled system capabilities and enable() it on this CPU.
2809  * The capabilities were decided based on the available CPUs at the boot time.
2810  * Any new CPU should match the system wide status of the capability. If the
2811  * new CPU doesn't have a capability which the system now has enabled, we
2812  * cannot do anything to fix it up and could cause unexpected failures. So
2813  * we park the CPU.
2814  */
2815 static void verify_local_cpu_capabilities(void)
2816 {
2817 	/*
2818 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2819 	 * check_early_cpu_features(), as they need to be verified
2820 	 * on all secondary CPUs.
2821 	 */
2822 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2823 	verify_local_elf_hwcaps();
2824 
2825 	if (system_supports_sve())
2826 		verify_sve_features();
2827 
2828 	if (is_hyp_mode_available())
2829 		verify_hyp_capabilities();
2830 }
2831 
2832 void check_local_cpu_capabilities(void)
2833 {
2834 	/*
2835 	 * All secondary CPUs should conform to the early CPU features
2836 	 * in use by the kernel based on boot CPU.
2837 	 */
2838 	check_early_cpu_features();
2839 
2840 	/*
2841 	 * If we haven't finalised the system capabilities, this CPU gets
2842 	 * a chance to update the errata work arounds and local features.
2843 	 * Otherwise, this CPU should verify that it has all the system
2844 	 * advertised capabilities.
2845 	 */
2846 	if (!system_capabilities_finalized())
2847 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2848 	else
2849 		verify_local_cpu_capabilities();
2850 }
2851 
2852 static void __init setup_boot_cpu_capabilities(void)
2853 {
2854 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2855 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2856 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2857 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2858 }
2859 
2860 bool this_cpu_has_cap(unsigned int n)
2861 {
2862 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2863 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2864 
2865 		if (cap)
2866 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2867 	}
2868 
2869 	return false;
2870 }
2871 EXPORT_SYMBOL_GPL(this_cpu_has_cap);
2872 
2873 /*
2874  * This helper function is used in a narrow window when,
2875  * - The system wide safe registers are set with all the SMP CPUs and,
2876  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2877  * In all other cases cpus_have_{const_}cap() should be used.
2878  */
2879 static bool __maybe_unused __system_matches_cap(unsigned int n)
2880 {
2881 	if (n < ARM64_NCAPS) {
2882 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2883 
2884 		if (cap)
2885 			return cap->matches(cap, SCOPE_SYSTEM);
2886 	}
2887 	return false;
2888 }
2889 
2890 void cpu_set_feature(unsigned int num)
2891 {
2892 	WARN_ON(num >= MAX_CPU_FEATURES);
2893 	elf_hwcap |= BIT(num);
2894 }
2895 EXPORT_SYMBOL_GPL(cpu_set_feature);
2896 
2897 bool cpu_have_feature(unsigned int num)
2898 {
2899 	WARN_ON(num >= MAX_CPU_FEATURES);
2900 	return elf_hwcap & BIT(num);
2901 }
2902 EXPORT_SYMBOL_GPL(cpu_have_feature);
2903 
2904 unsigned long cpu_get_elf_hwcap(void)
2905 {
2906 	/*
2907 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2908 	 * note that for userspace compatibility we guarantee that bits 62
2909 	 * and 63 will always be returned as 0.
2910 	 */
2911 	return lower_32_bits(elf_hwcap);
2912 }
2913 
2914 unsigned long cpu_get_elf_hwcap2(void)
2915 {
2916 	return upper_32_bits(elf_hwcap);
2917 }
2918 
2919 static void __init setup_system_capabilities(void)
2920 {
2921 	/*
2922 	 * We have finalised the system-wide safe feature
2923 	 * registers, finalise the capabilities that depend
2924 	 * on it. Also enable all the available capabilities,
2925 	 * that are not enabled already.
2926 	 */
2927 	update_cpu_capabilities(SCOPE_SYSTEM);
2928 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2929 }
2930 
2931 void __init setup_cpu_features(void)
2932 {
2933 	u32 cwg;
2934 
2935 	setup_system_capabilities();
2936 	setup_elf_hwcaps(arm64_elf_hwcaps);
2937 
2938 	if (system_supports_32bit_el0())
2939 		setup_elf_hwcaps(compat_elf_hwcaps);
2940 
2941 	if (system_uses_ttbr0_pan())
2942 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2943 
2944 	sve_setup();
2945 	minsigstksz_setup();
2946 
2947 	/* Advertise that we have computed the system capabilities */
2948 	finalize_system_capabilities();
2949 
2950 	/*
2951 	 * Check for sane CTR_EL0.CWG value.
2952 	 */
2953 	cwg = cache_type_cwg();
2954 	if (!cwg)
2955 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2956 			ARCH_DMA_MINALIGN);
2957 }
2958 
2959 static int enable_mismatched_32bit_el0(unsigned int cpu)
2960 {
2961 	/*
2962 	 * The first 32-bit-capable CPU we detected and so can no longer
2963 	 * be offlined by userspace. -1 indicates we haven't yet onlined
2964 	 * a 32-bit-capable CPU.
2965 	 */
2966 	static int lucky_winner = -1;
2967 
2968 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
2969 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
2970 
2971 	if (cpu_32bit) {
2972 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
2973 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
2974 	}
2975 
2976 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
2977 		return 0;
2978 
2979 	if (lucky_winner >= 0)
2980 		return 0;
2981 
2982 	/*
2983 	 * We've detected a mismatch. We need to keep one of our CPUs with
2984 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
2985 	 * every CPU in the system for a 32-bit task.
2986 	 */
2987 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
2988 							 cpu_active_mask);
2989 	get_cpu_device(lucky_winner)->offline_disabled = true;
2990 	setup_elf_hwcaps(compat_elf_hwcaps);
2991 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
2992 		cpu, lucky_winner);
2993 	return 0;
2994 }
2995 
2996 static int __init init_32bit_el0_mask(void)
2997 {
2998 	if (!allow_mismatched_32bit_el0)
2999 		return 0;
3000 
3001 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
3002 		return -ENOMEM;
3003 
3004 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
3005 				 "arm64/mismatched_32bit_el0:online",
3006 				 enable_mismatched_32bit_el0, NULL);
3007 }
3008 subsys_initcall_sync(init_32bit_el0_mask);
3009 
3010 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3011 {
3012 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
3013 }
3014 
3015 /*
3016  * We emulate only the following system register space.
3017  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
3018  * See Table C5-6 System instruction encodings for System register accesses,
3019  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3020  */
3021 static inline bool __attribute_const__ is_emulated(u32 id)
3022 {
3023 	return (sys_reg_Op0(id) == 0x3 &&
3024 		sys_reg_CRn(id) == 0x0 &&
3025 		sys_reg_Op1(id) == 0x0 &&
3026 		(sys_reg_CRm(id) == 0 ||
3027 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
3028 }
3029 
3030 /*
3031  * With CRm == 0, reg should be one of :
3032  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3033  */
3034 static inline int emulate_id_reg(u32 id, u64 *valp)
3035 {
3036 	switch (id) {
3037 	case SYS_MIDR_EL1:
3038 		*valp = read_cpuid_id();
3039 		break;
3040 	case SYS_MPIDR_EL1:
3041 		*valp = SYS_MPIDR_SAFE_VAL;
3042 		break;
3043 	case SYS_REVIDR_EL1:
3044 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3045 		*valp = 0;
3046 		break;
3047 	default:
3048 		return -EINVAL;
3049 	}
3050 
3051 	return 0;
3052 }
3053 
3054 static int emulate_sys_reg(u32 id, u64 *valp)
3055 {
3056 	struct arm64_ftr_reg *regp;
3057 
3058 	if (!is_emulated(id))
3059 		return -EINVAL;
3060 
3061 	if (sys_reg_CRm(id) == 0)
3062 		return emulate_id_reg(id, valp);
3063 
3064 	regp = get_arm64_ftr_reg_nowarn(id);
3065 	if (regp)
3066 		*valp = arm64_ftr_reg_user_value(regp);
3067 	else
3068 		/*
3069 		 * The untracked registers are either IMPLEMENTATION DEFINED
3070 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3071 		 */
3072 		*valp = 0;
3073 	return 0;
3074 }
3075 
3076 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3077 {
3078 	int rc;
3079 	u64 val;
3080 
3081 	rc = emulate_sys_reg(sys_reg, &val);
3082 	if (!rc) {
3083 		pt_regs_write_reg(regs, rt, val);
3084 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3085 	}
3086 	return rc;
3087 }
3088 
3089 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3090 {
3091 	u32 sys_reg, rt;
3092 
3093 	/*
3094 	 * sys_reg values are defined as used in mrs/msr instruction.
3095 	 * shift the imm value to get the encoding.
3096 	 */
3097 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3098 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3099 	return do_emulate_mrs(regs, sys_reg, rt);
3100 }
3101 
3102 static struct undef_hook mrs_hook = {
3103 	.instr_mask = 0xffff0000,
3104 	.instr_val  = 0xd5380000,
3105 	.pstate_mask = PSR_AA32_MODE_MASK,
3106 	.pstate_val = PSR_MODE_EL0t,
3107 	.fn = emulate_mrs,
3108 };
3109 
3110 static int __init enable_mrs_emulation(void)
3111 {
3112 	register_undef_hook(&mrs_hook);
3113 	return 0;
3114 }
3115 
3116 core_initcall(enable_mrs_emulation);
3117 
3118 enum mitigation_state arm64_get_meltdown_state(void)
3119 {
3120 	if (__meltdown_safe)
3121 		return SPECTRE_UNAFFECTED;
3122 
3123 	if (arm64_kernel_unmapped_at_el0())
3124 		return SPECTRE_MITIGATED;
3125 
3126 	return SPECTRE_VULNERABLE;
3127 }
3128 
3129 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3130 			  char *buf)
3131 {
3132 	switch (arm64_get_meltdown_state()) {
3133 	case SPECTRE_UNAFFECTED:
3134 		return sprintf(buf, "Not affected\n");
3135 
3136 	case SPECTRE_MITIGATED:
3137 		return sprintf(buf, "Mitigation: PTI\n");
3138 
3139 	default:
3140 		return sprintf(buf, "Vulnerable\n");
3141 	}
3142 }
3143