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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/percpu.h>
69 #include <linux/sort.h>
70 #include <linux/stop_machine.h>
71 #include <linux/sysfs.h>
72 #include <linux/types.h>
73 #include <linux/mm.h>
74 #include <linux/cpu.h>
75 #include <linux/kasan.h>
76 
77 #include <asm/cpu.h>
78 #include <asm/cpufeature.h>
79 #include <asm/cpu_ops.h>
80 #include <asm/fpsimd.h>
81 #include <asm/kvm_host.h>
82 #include <asm/hwcap.h>
83 #include <asm/mmu_context.h>
84 #include <asm/mte.h>
85 #include <asm/processor.h>
86 #include <asm/sysreg.h>
87 #include <asm/traps.h>
88 #include <asm/vectors.h>
89 #include <asm/virt.h>
90 
91 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
92 static unsigned long elf_hwcap __read_mostly;
93 
94 #ifdef CONFIG_COMPAT
95 #define COMPAT_ELF_HWCAP_DEFAULT	\
96 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
97 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
98 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
99 				 COMPAT_HWCAP_LPAE)
100 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
101 unsigned int compat_elf_hwcap2 __read_mostly;
102 #endif
103 
104 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
105 EXPORT_SYMBOL(cpu_hwcaps);
106 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
107 
108 /* Need also bit for ARM64_CB_PATCH */
109 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
110 
111 bool arm64_use_ng_mappings = false;
112 EXPORT_SYMBOL(arm64_use_ng_mappings);
113 
114 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
115 
116 /*
117  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
118  * support it?
119  */
120 static bool __read_mostly allow_mismatched_32bit_el0;
121 
122 /*
123  * Static branch enabled only if allow_mismatched_32bit_el0 is set and we have
124  * seen at least one CPU capable of 32-bit EL0.
125  */
126 DEFINE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
127 
128 /*
129  * Mask of CPUs supporting 32-bit EL0.
130  * Only valid if arm64_mismatched_32bit_el0 is enabled.
131  */
132 static cpumask_var_t cpu_32bit_el0_mask __cpumask_var_read_mostly;
133 
134 /*
135  * Flag to indicate if we have computed the system wide
136  * capabilities based on the boot time active CPUs. This
137  * will be used to determine if a new booting CPU should
138  * go through the verification process to make sure that it
139  * supports the system capabilities, without using a hotplug
140  * notifier. This is also used to decide if we could use
141  * the fast path for checking constant CPU caps.
142  */
143 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
144 EXPORT_SYMBOL(arm64_const_caps_ready);
finalize_system_capabilities(void)145 static inline void finalize_system_capabilities(void)
146 {
147 	static_branch_enable(&arm64_const_caps_ready);
148 }
149 
dump_cpu_features(void)150 void dump_cpu_features(void)
151 {
152 	/* file-wide pr_fmt adds "CPU features: " prefix */
153 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
154 }
155 
156 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
157 EXPORT_SYMBOL(cpu_hwcap_keys);
158 
159 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
160 	{						\
161 		.sign = SIGNED,				\
162 		.visible = VISIBLE,			\
163 		.strict = STRICT,			\
164 		.type = TYPE,				\
165 		.shift = SHIFT,				\
166 		.width = WIDTH,				\
167 		.safe_val = SAFE_VAL,			\
168 	}
169 
170 /* Define a feature with unsigned values */
171 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
172 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
173 
174 /* Define a feature with a signed value */
175 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
176 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
177 
178 #define ARM64_FTR_END					\
179 	{						\
180 		.width = 0,				\
181 	}
182 
183 /* meta feature for alternatives */
184 static bool __maybe_unused
185 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
186 
187 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
188 
189 static bool __system_matches_cap(unsigned int n);
190 
191 /*
192  * NOTE: Any changes to the visibility of features should be kept in
193  * sync with the documentation of the CPU feature register ABI.
194  */
195 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
210 	ARM64_FTR_END,
211 };
212 
213 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
214 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
215 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
217 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
218 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
219 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
221 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
223 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
228 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
229 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
230 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
231 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
232 	ARM64_FTR_END,
233 };
234 
235 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
236 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
237 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
238 	ARM64_FTR_END,
239 };
240 
241 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
244 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
245 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
246 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
247 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
248 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
249 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
250 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
251 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
252 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
253 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
254 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
255 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
256 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
257 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
258 	ARM64_FTR_END,
259 };
260 
261 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
262 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
263 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
264 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
265 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
266 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
267 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
268 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
269 	ARM64_FTR_END,
270 };
271 
272 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
273 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
274 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
276 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
277 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
278 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
279 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
280 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
281 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
282 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
283 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
284 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
285 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
286 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
287 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
288 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
289 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
290 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
291 	ARM64_FTR_END,
292 };
293 
294 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
295 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
296 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
297 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
298 	/*
299 	 * Page size not being supported at Stage-2 is not fatal. You
300 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
301 	 * your favourite nesting hypervisor.
302 	 *
303 	 * There is a small corner case where the hypervisor explicitly
304 	 * advertises a given granule size at Stage-2 (value 2) on some
305 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
306 	 * vCPUs. Although this is not forbidden by the architecture, it
307 	 * indicates that the hypervisor is being silly (or buggy).
308 	 *
309 	 * We make no effort to cope with this and pretend that if these
310 	 * fields are inconsistent across vCPUs, then it isn't worth
311 	 * trying to bring KVM up.
312 	 */
313 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
314 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
315 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
316 	/*
317 	 * We already refuse to boot CPUs that don't support our configured
318 	 * page size, so we can only detect mismatches for a page size other
319 	 * than the one we're currently using. Unfortunately, SoCs like this
320 	 * exist in the wild so, even though we don't like it, we'll have to go
321 	 * along with it and treat them as non-strict.
322 	 */
323 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
324 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
326 
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
328 	/* Linux shouldn't care about secure memory */
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
330 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
331 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
332 	/*
333 	 * Differing PARange is fine as long as all peripherals and memory are mapped
334 	 * within the minimum PARange of all CPUs
335 	 */
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
337 	ARM64_FTR_END,
338 };
339 
340 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
341 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
347 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
350 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
351 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
352 	ARM64_FTR_END,
353 };
354 
355 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
356 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
357 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
358 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
359 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
360 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
361 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
362 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
363 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
364 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
365 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
366 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
367 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
368 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
369 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
370 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
371 	ARM64_FTR_END,
372 };
373 
374 static const struct arm64_ftr_bits ftr_ctr[] = {
375 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
376 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
377 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
378 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
379 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
380 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
381 	/*
382 	 * Linux can handle differing I-cache policies. Userspace JITs will
383 	 * make use of *minLine.
384 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
385 	 */
386 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
387 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
388 	ARM64_FTR_END,
389 };
390 
391 static struct arm64_ftr_override __ro_after_init no_override = { };
392 
393 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
394 	.name		= "SYS_CTR_EL0",
395 	.ftr_bits	= ftr_ctr,
396 	.override	= &no_override,
397 };
398 
399 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
400 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
402 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
403 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
404 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
405 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
406 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
407 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
408 	ARM64_FTR_END,
409 };
410 
411 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
412 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
415 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
416 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
417 	/*
418 	 * We can instantiate multiple PMU instances with different levels
419 	 * of support.
420 	 */
421 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
422 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
423 	ARM64_FTR_END,
424 };
425 
426 static const struct arm64_ftr_bits ftr_mvfr2[] = {
427 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
428 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
429 	ARM64_FTR_END,
430 };
431 
432 static const struct arm64_ftr_bits ftr_dczid[] = {
433 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
434 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
435 	ARM64_FTR_END,
436 };
437 
438 static const struct arm64_ftr_bits ftr_id_isar0[] = {
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
443 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
444 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
445 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
446 	ARM64_FTR_END,
447 };
448 
449 static const struct arm64_ftr_bits ftr_id_isar5[] = {
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
451 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
456 	ARM64_FTR_END,
457 };
458 
459 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
460 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
461 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
462 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
463 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
464 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
465 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
466 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
467 
468 	/*
469 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
470 	 * external abort on speculative read. It is safe to assume that an
471 	 * SError might be generated than it will not be. Hence it has been
472 	 * classified as FTR_HIGHER_SAFE.
473 	 */
474 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
475 	ARM64_FTR_END,
476 };
477 
478 static const struct arm64_ftr_bits ftr_id_isar4[] = {
479 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
480 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
484 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
485 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
486 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
487 	ARM64_FTR_END,
488 };
489 
490 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
491 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
492 	ARM64_FTR_END,
493 };
494 
495 static const struct arm64_ftr_bits ftr_id_isar6[] = {
496 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
501 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
503 	ARM64_FTR_END,
504 };
505 
506 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
507 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
508 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
509 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
513 	ARM64_FTR_END,
514 };
515 
516 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
517 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
518 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
519 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
520 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
521 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
522 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
523 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
524 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
525 	ARM64_FTR_END,
526 };
527 
528 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
529 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
530 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
531 	ARM64_FTR_END,
532 };
533 
534 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
535 	/* [31:28] TraceFilt */
536 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_DFR0_PERFMON_SHIFT, 4, 0),
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
538 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
541 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
542 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
543 	ARM64_FTR_END,
544 };
545 
546 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
547 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
548 	ARM64_FTR_END,
549 };
550 
551 static const struct arm64_ftr_bits ftr_zcr[] = {
552 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
553 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
554 	ARM64_FTR_END,
555 };
556 
557 /*
558  * Common ftr bits for a 32bit register with all hidden, strict
559  * attributes, with 4bit feature fields and a default safe value of
560  * 0. Covers the following 32bit registers:
561  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
562  */
563 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
564 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
565 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
566 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
567 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
568 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
569 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
570 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
571 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
572 	ARM64_FTR_END,
573 };
574 
575 /* Table for a single 32bit feature value */
576 static const struct arm64_ftr_bits ftr_single32[] = {
577 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
578 	ARM64_FTR_END,
579 };
580 
581 static const struct arm64_ftr_bits ftr_raz[] = {
582 	ARM64_FTR_END,
583 };
584 
585 #define __ARM64_FTR_REG_OVERRIDE(id_str, id, table, ovr) {	\
586 		.sys_id = id,					\
587 		.reg = 	&(struct arm64_ftr_reg){		\
588 			.name = id_str,				\
589 			.override = (ovr),			\
590 			.ftr_bits = &((table)[0]),		\
591 	}}
592 
593 #define ARM64_FTR_REG_OVERRIDE(id, table, ovr)	\
594 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, ovr)
595 
596 #define ARM64_FTR_REG(id, table)		\
597 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
598 
599 struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override;
600 struct arm64_ftr_override __ro_after_init id_aa64pfr1_override;
601 struct arm64_ftr_override __ro_after_init id_aa64isar1_override;
602 
603 static const struct __ftr_reg_entry {
604 	u32			sys_id;
605 	struct arm64_ftr_reg 	*reg;
606 } arm64_ftr_regs[] = {
607 
608 	/* Op1 = 0, CRn = 0, CRm = 1 */
609 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
610 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
611 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
612 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
613 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
614 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
615 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
616 
617 	/* Op1 = 0, CRn = 0, CRm = 2 */
618 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
619 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
620 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
621 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
622 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
623 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
624 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
625 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
626 
627 	/* Op1 = 0, CRn = 0, CRm = 3 */
628 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
629 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
630 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
631 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
632 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
633 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
634 
635 	/* Op1 = 0, CRn = 0, CRm = 4 */
636 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
637 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1,
638 			       &id_aa64pfr1_override),
639 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
640 
641 	/* Op1 = 0, CRn = 0, CRm = 5 */
642 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
643 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
644 
645 	/* Op1 = 0, CRn = 0, CRm = 6 */
646 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
647 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1,
648 			       &id_aa64isar1_override),
649 	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
650 
651 	/* Op1 = 0, CRn = 0, CRm = 7 */
652 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
653 	ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1,
654 			       &id_aa64mmfr1_override),
655 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
656 
657 	/* Op1 = 0, CRn = 1, CRm = 2 */
658 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
659 
660 	/* Op1 = 3, CRn = 0, CRm = 0 */
661 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
662 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
663 
664 	/* Op1 = 3, CRn = 14, CRm = 0 */
665 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
666 };
667 
search_cmp_ftr_reg(const void * id,const void * regp)668 static int search_cmp_ftr_reg(const void *id, const void *regp)
669 {
670 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
671 }
672 
673 /*
674  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
675  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
676  * ascending order of sys_id, we use binary search to find a matching
677  * entry.
678  *
679  * returns - Upon success,  matching ftr_reg entry for id.
680  *         - NULL on failure. It is upto the caller to decide
681  *	     the impact of a failure.
682  */
get_arm64_ftr_reg_nowarn(u32 sys_id)683 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
684 {
685 	const struct __ftr_reg_entry *ret;
686 
687 	ret = bsearch((const void *)(unsigned long)sys_id,
688 			arm64_ftr_regs,
689 			ARRAY_SIZE(arm64_ftr_regs),
690 			sizeof(arm64_ftr_regs[0]),
691 			search_cmp_ftr_reg);
692 	if (ret)
693 		return ret->reg;
694 	return NULL;
695 }
696 
697 /*
698  * get_arm64_ftr_reg - Looks up a feature register entry using
699  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
700  *
701  * returns - Upon success,  matching ftr_reg entry for id.
702  *         - NULL on failure but with an WARN_ON().
703  */
get_arm64_ftr_reg(u32 sys_id)704 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
705 {
706 	struct arm64_ftr_reg *reg;
707 
708 	reg = get_arm64_ftr_reg_nowarn(sys_id);
709 
710 	/*
711 	 * Requesting a non-existent register search is an error. Warn
712 	 * and let the caller handle it.
713 	 */
714 	WARN_ON(!reg);
715 	return reg;
716 }
717 
arm64_ftr_set_value(const struct arm64_ftr_bits * ftrp,s64 reg,s64 ftr_val)718 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
719 			       s64 ftr_val)
720 {
721 	u64 mask = arm64_ftr_mask(ftrp);
722 
723 	reg &= ~mask;
724 	reg |= (ftr_val << ftrp->shift) & mask;
725 	return reg;
726 }
727 
arm64_ftr_safe_value(const struct arm64_ftr_bits * ftrp,s64 new,s64 cur)728 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
729 				s64 cur)
730 {
731 	s64 ret = 0;
732 
733 	switch (ftrp->type) {
734 	case FTR_EXACT:
735 		ret = ftrp->safe_val;
736 		break;
737 	case FTR_LOWER_SAFE:
738 		ret = new < cur ? new : cur;
739 		break;
740 	case FTR_HIGHER_OR_ZERO_SAFE:
741 		if (!cur || !new)
742 			break;
743 		fallthrough;
744 	case FTR_HIGHER_SAFE:
745 		ret = new > cur ? new : cur;
746 		break;
747 	default:
748 		BUG();
749 	}
750 
751 	return ret;
752 }
753 
sort_ftr_regs(void)754 static void __init sort_ftr_regs(void)
755 {
756 	unsigned int i;
757 
758 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
759 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
760 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
761 		unsigned int j = 0;
762 
763 		/*
764 		 * Features here must be sorted in descending order with respect
765 		 * to their shift values and should not overlap with each other.
766 		 */
767 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
768 			unsigned int width = ftr_reg->ftr_bits[j].width;
769 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
770 			unsigned int prev_shift;
771 
772 			WARN((shift  + width) > 64,
773 				"%s has invalid feature at shift %d\n",
774 				ftr_reg->name, shift);
775 
776 			/*
777 			 * Skip the first feature. There is nothing to
778 			 * compare against for now.
779 			 */
780 			if (j == 0)
781 				continue;
782 
783 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
784 			WARN((shift + width) > prev_shift,
785 				"%s has feature overlap at shift %d\n",
786 				ftr_reg->name, shift);
787 		}
788 
789 		/*
790 		 * Skip the first register. There is nothing to
791 		 * compare against for now.
792 		 */
793 		if (i == 0)
794 			continue;
795 		/*
796 		 * Registers here must be sorted in ascending order with respect
797 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
798 		 * to work correctly.
799 		 */
800 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
801 	}
802 }
803 
804 /*
805  * Initialise the CPU feature register from Boot CPU values.
806  * Also initiliases the strict_mask for the register.
807  * Any bits that are not covered by an arm64_ftr_bits entry are considered
808  * RES0 for the system-wide value, and must strictly match.
809  */
init_cpu_ftr_reg(u32 sys_reg,u64 new)810 static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
811 {
812 	u64 val = 0;
813 	u64 strict_mask = ~0x0ULL;
814 	u64 user_mask = 0;
815 	u64 valid_mask = 0;
816 
817 	const struct arm64_ftr_bits *ftrp;
818 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
819 
820 	if (!reg)
821 		return;
822 
823 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
824 		u64 ftr_mask = arm64_ftr_mask(ftrp);
825 		s64 ftr_new = arm64_ftr_value(ftrp, new);
826 		s64 ftr_ovr = arm64_ftr_value(ftrp, reg->override->val);
827 
828 		if ((ftr_mask & reg->override->mask) == ftr_mask) {
829 			s64 tmp = arm64_ftr_safe_value(ftrp, ftr_ovr, ftr_new);
830 			char *str = NULL;
831 
832 			if (ftr_ovr != tmp) {
833 				/* Unsafe, remove the override */
834 				reg->override->mask &= ~ftr_mask;
835 				reg->override->val &= ~ftr_mask;
836 				tmp = ftr_ovr;
837 				str = "ignoring override";
838 			} else if (ftr_new != tmp) {
839 				/* Override was valid */
840 				ftr_new = tmp;
841 				str = "forced";
842 			} else if (ftr_ovr == tmp) {
843 				/* Override was the safe value */
844 				str = "already set";
845 			}
846 
847 			if (str)
848 				pr_warn("%s[%d:%d]: %s to %llx\n",
849 					reg->name,
850 					ftrp->shift + ftrp->width - 1,
851 					ftrp->shift, str, tmp);
852 		}
853 
854 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
855 
856 		valid_mask |= ftr_mask;
857 		if (!ftrp->strict)
858 			strict_mask &= ~ftr_mask;
859 		if (ftrp->visible)
860 			user_mask |= ftr_mask;
861 		else
862 			reg->user_val = arm64_ftr_set_value(ftrp,
863 							    reg->user_val,
864 							    ftrp->safe_val);
865 	}
866 
867 	val &= valid_mask;
868 
869 	reg->sys_val = val;
870 	reg->strict_mask = strict_mask;
871 	reg->user_mask = user_mask;
872 }
873 
874 extern const struct arm64_cpu_capabilities arm64_errata[];
875 static const struct arm64_cpu_capabilities arm64_features[];
876 
877 static void __init
init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities * caps)878 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
879 {
880 	for (; caps->matches; caps++) {
881 		if (WARN(caps->capability >= ARM64_NCAPS,
882 			"Invalid capability %d\n", caps->capability))
883 			continue;
884 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
885 			"Duplicate entry for capability %d\n",
886 			caps->capability))
887 			continue;
888 		cpu_hwcaps_ptrs[caps->capability] = caps;
889 	}
890 }
891 
init_cpu_hwcaps_indirect_list(void)892 static void __init init_cpu_hwcaps_indirect_list(void)
893 {
894 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
895 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
896 }
897 
898 static void __init setup_boot_cpu_capabilities(void);
899 
init_32bit_cpu_features(struct cpuinfo_32bit * info)900 static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
901 {
902 	init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
903 	init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
904 	init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
905 	init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
906 	init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
907 	init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
908 	init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
909 	init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
910 	init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
911 	init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
912 	init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
913 	init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
914 	init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
915 	init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
916 	init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
917 	init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
918 	init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
919 	init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
920 	init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
921 	init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
922 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
923 }
924 
init_cpu_features(struct cpuinfo_arm64 * info)925 void __init init_cpu_features(struct cpuinfo_arm64 *info)
926 {
927 	/* Before we start using the tables, make sure it is sorted */
928 	sort_ftr_regs();
929 
930 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
931 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
932 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
933 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
934 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
935 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
936 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
937 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
938 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
939 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
940 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
941 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
942 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
943 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
944 
945 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0))
946 		init_32bit_cpu_features(&info->aarch32);
947 
948 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
949 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
950 		sve_init_vq_map();
951 	}
952 
953 	/*
954 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
955 	 * before we handle the boot CPU below.
956 	 */
957 	init_cpu_hwcaps_indirect_list();
958 
959 	/*
960 	 * Detect and enable early CPU capabilities based on the boot CPU,
961 	 * after we have initialised the CPU feature infrastructure.
962 	 */
963 	setup_boot_cpu_capabilities();
964 }
965 
update_cpu_ftr_reg(struct arm64_ftr_reg * reg,u64 new)966 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
967 {
968 	const struct arm64_ftr_bits *ftrp;
969 
970 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
971 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
972 		s64 ftr_new = arm64_ftr_value(ftrp, new);
973 
974 		if (ftr_cur == ftr_new)
975 			continue;
976 		/* Find a safe value */
977 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
978 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
979 	}
980 
981 }
982 
check_update_ftr_reg(u32 sys_id,int cpu,u64 val,u64 boot)983 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
984 {
985 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
986 
987 	if (!regp)
988 		return 0;
989 
990 	update_cpu_ftr_reg(regp, val);
991 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
992 		return 0;
993 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
994 			regp->name, boot, cpu, val);
995 	return 1;
996 }
997 
relax_cpu_ftr_reg(u32 sys_id,int field)998 static void relax_cpu_ftr_reg(u32 sys_id, int field)
999 {
1000 	const struct arm64_ftr_bits *ftrp;
1001 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
1002 
1003 	if (!regp)
1004 		return;
1005 
1006 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
1007 		if (ftrp->shift == field) {
1008 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
1009 			break;
1010 		}
1011 	}
1012 
1013 	/* Bogus field? */
1014 	WARN_ON(!ftrp->width);
1015 }
1016 
update_mismatched_32bit_el0_cpu_features(struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)1017 static void update_mismatched_32bit_el0_cpu_features(struct cpuinfo_arm64 *info,
1018 						     struct cpuinfo_arm64 *boot)
1019 {
1020 	static bool boot_cpu_32bit_regs_overridden = false;
1021 
1022 	if (!allow_mismatched_32bit_el0 || boot_cpu_32bit_regs_overridden)
1023 		return;
1024 
1025 	if (id_aa64pfr0_32bit_el0(boot->reg_id_aa64pfr0))
1026 		return;
1027 
1028 	boot->aarch32 = info->aarch32;
1029 	init_32bit_cpu_features(&boot->aarch32);
1030 	boot_cpu_32bit_regs_overridden = true;
1031 }
1032 
update_32bit_cpu_features(int cpu,struct cpuinfo_32bit * info,struct cpuinfo_32bit * boot)1033 static int update_32bit_cpu_features(int cpu, struct cpuinfo_32bit *info,
1034 				     struct cpuinfo_32bit *boot)
1035 {
1036 	int taint = 0;
1037 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1038 
1039 	/*
1040 	 * If we don't have AArch32 at EL1, then relax the strictness of
1041 	 * EL1-dependent register fields to avoid spurious sanity check fails.
1042 	 */
1043 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
1044 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
1045 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
1046 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
1047 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
1048 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
1049 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
1050 	}
1051 
1052 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
1053 				      info->reg_id_dfr0, boot->reg_id_dfr0);
1054 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
1055 				      info->reg_id_dfr1, boot->reg_id_dfr1);
1056 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
1057 				      info->reg_id_isar0, boot->reg_id_isar0);
1058 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
1059 				      info->reg_id_isar1, boot->reg_id_isar1);
1060 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
1061 				      info->reg_id_isar2, boot->reg_id_isar2);
1062 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
1063 				      info->reg_id_isar3, boot->reg_id_isar3);
1064 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
1065 				      info->reg_id_isar4, boot->reg_id_isar4);
1066 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
1067 				      info->reg_id_isar5, boot->reg_id_isar5);
1068 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
1069 				      info->reg_id_isar6, boot->reg_id_isar6);
1070 
1071 	/*
1072 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
1073 	 * ACTLR formats could differ across CPUs and therefore would have to
1074 	 * be trapped for virtualization anyway.
1075 	 */
1076 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1077 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1078 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1079 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1080 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1081 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1082 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1083 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1084 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1085 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1086 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1087 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1088 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1089 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1090 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1091 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1092 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1093 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1094 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1095 				      info->reg_mvfr0, boot->reg_mvfr0);
1096 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1097 				      info->reg_mvfr1, boot->reg_mvfr1);
1098 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1099 				      info->reg_mvfr2, boot->reg_mvfr2);
1100 
1101 	return taint;
1102 }
1103 
1104 /*
1105  * Update system wide CPU feature registers with the values from a
1106  * non-boot CPU. Also performs SANITY checks to make sure that there
1107  * aren't any insane variations from that of the boot CPU.
1108  */
update_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)1109 void update_cpu_features(int cpu,
1110 			 struct cpuinfo_arm64 *info,
1111 			 struct cpuinfo_arm64 *boot)
1112 {
1113 	int taint = 0;
1114 
1115 	/*
1116 	 * The kernel can handle differing I-cache policies, but otherwise
1117 	 * caches should look identical. Userspace JITs will make use of
1118 	 * *minLine.
1119 	 */
1120 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1121 				      info->reg_ctr, boot->reg_ctr);
1122 
1123 	/*
1124 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1125 	 * could result in too much or too little memory being zeroed if a
1126 	 * process is preempted and migrated between CPUs.
1127 	 */
1128 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1129 				      info->reg_dczid, boot->reg_dczid);
1130 
1131 	/* If different, timekeeping will be broken (especially with KVM) */
1132 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1133 				      info->reg_cntfrq, boot->reg_cntfrq);
1134 
1135 	/*
1136 	 * The kernel uses self-hosted debug features and expects CPUs to
1137 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1138 	 * and BRPs to be identical.
1139 	 * ID_AA64DFR1 is currently RES0.
1140 	 */
1141 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1142 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1143 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1144 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1145 	/*
1146 	 * Even in big.LITTLE, processors should be identical instruction-set
1147 	 * wise.
1148 	 */
1149 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1150 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1151 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1152 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1153 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1154 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1155 
1156 	/*
1157 	 * Differing PARange support is fine as long as all peripherals and
1158 	 * memory are mapped within the minimum PARange of all CPUs.
1159 	 * Linux should not care about secure memory.
1160 	 */
1161 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1162 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1163 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1164 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1165 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1166 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1167 
1168 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1169 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1170 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1171 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1172 
1173 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1174 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1175 
1176 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1177 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1178 					info->reg_zcr, boot->reg_zcr);
1179 
1180 		/* Probe vector lengths, unless we already gave up on SVE */
1181 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1182 		    !system_capabilities_finalized())
1183 			sve_update_vq_map();
1184 	}
1185 
1186 	/*
1187 	 * If we don't have AArch32 at all then skip the checks entirely
1188 	 * as the register values may be UNKNOWN and we're not going to be
1189 	 * using them for anything.
1190 	 *
1191 	 * This relies on a sanitised view of the AArch64 ID registers
1192 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1193 	 */
1194 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
1195 		update_mismatched_32bit_el0_cpu_features(info, boot);
1196 		taint |= update_32bit_cpu_features(cpu, &info->aarch32,
1197 						   &boot->aarch32);
1198 	}
1199 
1200 	/*
1201 	 * Mismatched CPU features are a recipe for disaster. Don't even
1202 	 * pretend to support them.
1203 	 */
1204 	if (taint) {
1205 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1206 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1207 	}
1208 }
1209 
read_sanitised_ftr_reg(u32 id)1210 u64 read_sanitised_ftr_reg(u32 id)
1211 {
1212 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1213 
1214 	if (!regp)
1215 		return 0;
1216 	return regp->sys_val;
1217 }
1218 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1219 
1220 #define read_sysreg_case(r)	\
1221 	case r:		val = read_sysreg_s(r); break;
1222 
1223 /*
1224  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1225  * Read the system register on the current CPU
1226  */
__read_sysreg_by_encoding(u32 sys_id)1227 u64 __read_sysreg_by_encoding(u32 sys_id)
1228 {
1229 	struct arm64_ftr_reg *regp;
1230 	u64 val;
1231 
1232 	switch (sys_id) {
1233 	read_sysreg_case(SYS_ID_PFR0_EL1);
1234 	read_sysreg_case(SYS_ID_PFR1_EL1);
1235 	read_sysreg_case(SYS_ID_PFR2_EL1);
1236 	read_sysreg_case(SYS_ID_DFR0_EL1);
1237 	read_sysreg_case(SYS_ID_DFR1_EL1);
1238 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1239 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1240 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1241 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1242 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1243 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1244 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1245 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1246 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1247 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1248 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1249 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1250 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1251 	read_sysreg_case(SYS_MVFR0_EL1);
1252 	read_sysreg_case(SYS_MVFR1_EL1);
1253 	read_sysreg_case(SYS_MVFR2_EL1);
1254 
1255 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1256 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1257 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1258 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1259 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1260 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1261 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1262 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1263 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1264 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1265 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1266 
1267 	read_sysreg_case(SYS_CNTFRQ_EL0);
1268 	read_sysreg_case(SYS_CTR_EL0);
1269 	read_sysreg_case(SYS_DCZID_EL0);
1270 
1271 	default:
1272 		BUG();
1273 		return 0;
1274 	}
1275 
1276 	regp  = get_arm64_ftr_reg(sys_id);
1277 	if (regp) {
1278 		val &= ~regp->override->mask;
1279 		val |= (regp->override->val & regp->override->mask);
1280 	}
1281 
1282 	return val;
1283 }
1284 
1285 #include <linux/irqchip/arm-gic-v3.h>
1286 
1287 static bool
feature_matches(u64 reg,const struct arm64_cpu_capabilities * entry)1288 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1289 {
1290 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1291 
1292 	return val >= entry->min_field_value;
1293 }
1294 
1295 static bool
has_cpuid_feature(const struct arm64_cpu_capabilities * entry,int scope)1296 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1297 {
1298 	u64 val;
1299 
1300 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1301 	if (scope == SCOPE_SYSTEM)
1302 		val = read_sanitised_ftr_reg(entry->sys_reg);
1303 	else
1304 		val = __read_sysreg_by_encoding(entry->sys_reg);
1305 
1306 	return feature_matches(val, entry);
1307 }
1308 
system_32bit_el0_cpumask(void)1309 const struct cpumask *system_32bit_el0_cpumask(void)
1310 {
1311 	if (!system_supports_32bit_el0())
1312 		return cpu_none_mask;
1313 
1314 	if (static_branch_unlikely(&arm64_mismatched_32bit_el0))
1315 		return cpu_32bit_el0_mask;
1316 
1317 	return cpu_possible_mask;
1318 }
1319 EXPORT_SYMBOL_GPL(system_32bit_el0_cpumask);
1320 
parse_32bit_el0_param(char * str)1321 static int __init parse_32bit_el0_param(char *str)
1322 {
1323 	allow_mismatched_32bit_el0 = true;
1324 	return 0;
1325 }
1326 early_param("allow_mismatched_32bit_el0", parse_32bit_el0_param);
1327 
aarch32_el0_show(struct device * dev,struct device_attribute * attr,char * buf)1328 static ssize_t aarch32_el0_show(struct device *dev,
1329 				struct device_attribute *attr, char *buf)
1330 {
1331 	const struct cpumask *mask = system_32bit_el0_cpumask();
1332 
1333 	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(mask));
1334 }
1335 static const DEVICE_ATTR_RO(aarch32_el0);
1336 
aarch32_el0_sysfs_init(void)1337 static int __init aarch32_el0_sysfs_init(void)
1338 {
1339 	if (!allow_mismatched_32bit_el0)
1340 		return 0;
1341 
1342 	return device_create_file(cpu_subsys.dev_root, &dev_attr_aarch32_el0);
1343 }
1344 device_initcall(aarch32_el0_sysfs_init);
1345 
has_32bit_el0(const struct arm64_cpu_capabilities * entry,int scope)1346 static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
1347 {
1348 	if (!has_cpuid_feature(entry, scope))
1349 		return allow_mismatched_32bit_el0;
1350 
1351 	if (scope == SCOPE_SYSTEM)
1352 		pr_info("detected: 32-bit EL0 Support\n");
1353 
1354 	return true;
1355 }
1356 
has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities * entry,int scope)1357 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1358 {
1359 	bool has_sre;
1360 
1361 	if (!has_cpuid_feature(entry, scope))
1362 		return false;
1363 
1364 	has_sre = gic_enable_sre();
1365 	if (!has_sre)
1366 		pr_warn_once("%s present but disabled by higher exception level\n",
1367 			     entry->desc);
1368 
1369 	return has_sre;
1370 }
1371 
has_no_hw_prefetch(const struct arm64_cpu_capabilities * entry,int __unused)1372 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1373 {
1374 	u32 midr = read_cpuid_id();
1375 
1376 	/* Cavium ThunderX pass 1.x and 2.x */
1377 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1378 		MIDR_CPU_VAR_REV(0, 0),
1379 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1380 }
1381 
has_no_fpsimd(const struct arm64_cpu_capabilities * entry,int __unused)1382 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1383 {
1384 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1385 
1386 	return cpuid_feature_extract_signed_field(pfr0,
1387 					ID_AA64PFR0_FP_SHIFT) < 0;
1388 }
1389 
has_cache_idc(const struct arm64_cpu_capabilities * entry,int scope)1390 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1391 			  int scope)
1392 {
1393 	u64 ctr;
1394 
1395 	if (scope == SCOPE_SYSTEM)
1396 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1397 	else
1398 		ctr = read_cpuid_effective_cachetype();
1399 
1400 	return ctr & BIT(CTR_IDC_SHIFT);
1401 }
1402 
cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities * __unused)1403 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1404 {
1405 	/*
1406 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1407 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1408 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1409 	 * value.
1410 	 */
1411 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1412 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1413 }
1414 
has_cache_dic(const struct arm64_cpu_capabilities * entry,int scope)1415 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1416 			  int scope)
1417 {
1418 	u64 ctr;
1419 
1420 	if (scope == SCOPE_SYSTEM)
1421 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1422 	else
1423 		ctr = read_cpuid_cachetype();
1424 
1425 	return ctr & BIT(CTR_DIC_SHIFT);
1426 }
1427 
1428 static bool __maybe_unused
has_useable_cnp(const struct arm64_cpu_capabilities * entry,int scope)1429 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1430 {
1431 	/*
1432 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1433 	 * may share TLB entries with a CPU stuck in the crashed
1434 	 * kernel.
1435 	 */
1436 	 if (is_kdump_kernel())
1437 		return false;
1438 
1439 	return has_cpuid_feature(entry, scope);
1440 }
1441 
1442 /*
1443  * This check is triggered during the early boot before the cpufeature
1444  * is initialised. Checking the status on the local CPU allows the boot
1445  * CPU to detect the need for non-global mappings and thus avoiding a
1446  * pagetable re-write after all the CPUs are booted. This check will be
1447  * anyway run on individual CPUs, allowing us to get the consistent
1448  * state once the SMP CPUs are up and thus make the switch to non-global
1449  * mappings if required.
1450  */
kaslr_requires_kpti(void)1451 bool kaslr_requires_kpti(void)
1452 {
1453 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1454 		return false;
1455 
1456 	/*
1457 	 * E0PD does a similar job to KPTI so can be used instead
1458 	 * where available.
1459 	 */
1460 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1461 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1462 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1463 						ID_AA64MMFR2_E0PD_SHIFT))
1464 			return false;
1465 	}
1466 
1467 	/*
1468 	 * Systems affected by Cavium erratum 24756 are incompatible
1469 	 * with KPTI.
1470 	 */
1471 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1472 		extern const struct midr_range cavium_erratum_27456_cpus[];
1473 
1474 		if (is_midr_in_range_list(read_cpuid_id(),
1475 					  cavium_erratum_27456_cpus))
1476 			return false;
1477 	}
1478 
1479 	return kaslr_offset() > 0;
1480 }
1481 
1482 static bool __meltdown_safe = true;
1483 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1484 
unmap_kernel_at_el0(const struct arm64_cpu_capabilities * entry,int scope)1485 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1486 				int scope)
1487 {
1488 	/* List of CPUs that are not vulnerable and don't need KPTI */
1489 	static const struct midr_range kpti_safe_list[] = {
1490 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1491 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1492 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1493 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1494 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1495 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1496 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1497 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1498 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1499 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1500 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1501 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1502 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1503 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1504 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1505 		{ /* sentinel */ }
1506 	};
1507 	char const *str = "kpti command line option";
1508 	bool meltdown_safe;
1509 
1510 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1511 
1512 	/* Defer to CPU feature registers */
1513 	if (has_cpuid_feature(entry, scope))
1514 		meltdown_safe = true;
1515 
1516 	if (!meltdown_safe)
1517 		__meltdown_safe = false;
1518 
1519 	/*
1520 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1521 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1522 	 * ends as well as you might imagine. Don't even try.
1523 	 */
1524 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1525 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1526 		__kpti_forced = -1;
1527 	}
1528 
1529 	/* Useful for KASLR robustness */
1530 	if (kaslr_requires_kpti()) {
1531 		if (!__kpti_forced) {
1532 			str = "KASLR";
1533 			__kpti_forced = 1;
1534 		}
1535 	}
1536 
1537 	if (cpu_mitigations_off() && !__kpti_forced) {
1538 		str = "mitigations=off";
1539 		__kpti_forced = -1;
1540 	}
1541 
1542 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1543 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1544 		return false;
1545 	}
1546 
1547 	/* Forced? */
1548 	if (__kpti_forced) {
1549 		pr_info_once("kernel page table isolation forced %s by %s\n",
1550 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1551 		return __kpti_forced > 0;
1552 	}
1553 
1554 	return !meltdown_safe;
1555 }
1556 
1557 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1558 static void __nocfi
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1559 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1560 {
1561 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1562 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1563 	kpti_remap_fn *remap_fn;
1564 
1565 	int cpu = smp_processor_id();
1566 
1567 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1568 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1569 
1570 		__this_cpu_write(this_cpu_vector, v);
1571 	}
1572 
1573 	/*
1574 	 * We don't need to rewrite the page-tables if either we've done
1575 	 * it already or we have KASLR enabled and therefore have not
1576 	 * created any global mappings at all.
1577 	 */
1578 	if (arm64_use_ng_mappings)
1579 		return;
1580 
1581 	remap_fn = (void *)__pa_function(idmap_kpti_install_ng_mappings);
1582 
1583 	cpu_install_idmap();
1584 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1585 	cpu_uninstall_idmap();
1586 
1587 	if (!cpu)
1588 		arm64_use_ng_mappings = true;
1589 
1590 	return;
1591 }
1592 #else
1593 static void
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1594 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1595 {
1596 }
1597 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1598 
parse_kpti(char * str)1599 static int __init parse_kpti(char *str)
1600 {
1601 	bool enabled;
1602 	int ret = strtobool(str, &enabled);
1603 
1604 	if (ret)
1605 		return ret;
1606 
1607 	__kpti_forced = enabled ? 1 : -1;
1608 	return 0;
1609 }
1610 early_param("kpti", parse_kpti);
1611 
1612 #ifdef CONFIG_ARM64_HW_AFDBM
__cpu_enable_hw_dbm(void)1613 static inline void __cpu_enable_hw_dbm(void)
1614 {
1615 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1616 
1617 	write_sysreg(tcr, tcr_el1);
1618 	isb();
1619 	local_flush_tlb_all();
1620 }
1621 
cpu_has_broken_dbm(void)1622 static bool cpu_has_broken_dbm(void)
1623 {
1624 	/* List of CPUs which have broken DBM support. */
1625 	static const struct midr_range cpus[] = {
1626 #ifdef CONFIG_ARM64_ERRATUM_1024718
1627 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1628 		/* Kryo4xx Silver (rdpe => r1p0) */
1629 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1630 #endif
1631 #ifdef CONFIG_ARM64_ERRATUM_2051678
1632 		MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
1633 #endif
1634 		{},
1635 	};
1636 
1637 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1638 }
1639 
cpu_can_use_dbm(const struct arm64_cpu_capabilities * cap)1640 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1641 {
1642 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1643 	       !cpu_has_broken_dbm();
1644 }
1645 
cpu_enable_hw_dbm(struct arm64_cpu_capabilities const * cap)1646 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1647 {
1648 	if (cpu_can_use_dbm(cap))
1649 		__cpu_enable_hw_dbm();
1650 }
1651 
has_hw_dbm(const struct arm64_cpu_capabilities * cap,int __unused)1652 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1653 		       int __unused)
1654 {
1655 	static bool detected = false;
1656 	/*
1657 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1658 	 * run a mix of CPUs with and without the feature. So, we
1659 	 * unconditionally enable the capability to allow any late CPU
1660 	 * to use the feature. We only enable the control bits on the
1661 	 * CPU, if it actually supports.
1662 	 *
1663 	 * We have to make sure we print the "feature" detection only
1664 	 * when at least one CPU actually uses it. So check if this CPU
1665 	 * can actually use it and print the message exactly once.
1666 	 *
1667 	 * This is safe as all CPUs (including secondary CPUs - due to the
1668 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1669 	 * goes through the "matches" check exactly once. Also if a CPU
1670 	 * matches the criteria, it is guaranteed that the CPU will turn
1671 	 * the DBM on, as the capability is unconditionally enabled.
1672 	 */
1673 	if (!detected && cpu_can_use_dbm(cap)) {
1674 		detected = true;
1675 		pr_info("detected: Hardware dirty bit management\n");
1676 	}
1677 
1678 	return true;
1679 }
1680 
1681 #endif
1682 
1683 #ifdef CONFIG_ARM64_AMU_EXTN
1684 
1685 /*
1686  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1687  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1688  * information regarding all the events that it supports. When a CPU bit is
1689  * set in the cpumask, the user of this feature can only rely on the presence
1690  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1691  * counters are enabled or access to these counters is enabled by code
1692  * executed at higher exception levels (firmware).
1693  */
1694 static struct cpumask amu_cpus __read_mostly;
1695 
cpu_has_amu_feat(int cpu)1696 bool cpu_has_amu_feat(int cpu)
1697 {
1698 	return cpumask_test_cpu(cpu, &amu_cpus);
1699 }
1700 
1701 /* Initialize the use of AMU counters for frequency invariance */
1702 extern void init_cpu_freq_invariance_counters(void);
1703 
cpu_amu_enable(struct arm64_cpu_capabilities const * cap)1704 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1705 {
1706 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1707 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1708 			smp_processor_id());
1709 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1710 
1711 		/* 0 reference values signal broken/disabled counters */
1712 		if (!this_cpu_has_cap(ARM64_WORKAROUND_2457168))
1713 			init_cpu_freq_invariance_counters();
1714 	}
1715 }
1716 
has_amu(const struct arm64_cpu_capabilities * cap,int __unused)1717 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1718 		    int __unused)
1719 {
1720 	/*
1721 	 * The AMU extension is a non-conflicting feature: the kernel can
1722 	 * safely run a mix of CPUs with and without support for the
1723 	 * activity monitors extension. Therefore, unconditionally enable
1724 	 * the capability to allow any late CPU to use the feature.
1725 	 *
1726 	 * With this feature unconditionally enabled, the cpu_enable
1727 	 * function will be called for all CPUs that match the criteria,
1728 	 * including secondary and hotplugged, marking this feature as
1729 	 * present on that respective CPU. The enable function will also
1730 	 * print a detection message.
1731 	 */
1732 
1733 	return true;
1734 }
1735 #endif
1736 
1737 #ifdef CONFIG_ARM64_VHE
runs_at_el2(const struct arm64_cpu_capabilities * entry,int __unused)1738 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1739 {
1740 	return is_kernel_in_hyp_mode();
1741 }
1742 
cpu_copy_el2regs(const struct arm64_cpu_capabilities * __unused)1743 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1744 {
1745 	/*
1746 	 * Copy register values that aren't redirected by hardware.
1747 	 *
1748 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1749 	 * this value to tpidr_el2 before we patch the code. Once we've done
1750 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1751 	 * do anything here.
1752 	 */
1753 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1754 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1755 }
1756 #endif
1757 
cpu_has_fwb(const struct arm64_cpu_capabilities * __unused)1758 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1759 {
1760 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1761 
1762 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1763 	WARN_ON(val & (7 << 27 | 7 << 21));
1764 }
1765 
1766 #ifdef CONFIG_ARM64_PAN
cpu_enable_pan(const struct arm64_cpu_capabilities * __unused)1767 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1768 {
1769 	/*
1770 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1771 	 * is discarded once we return from the exception.
1772 	 */
1773 	WARN_ON_ONCE(in_interrupt());
1774 
1775 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1776 	set_pstate_pan(1);
1777 }
1778 #endif /* CONFIG_ARM64_PAN */
1779 
1780 #ifdef CONFIG_ARM64_RAS_EXTN
cpu_clear_disr(const struct arm64_cpu_capabilities * __unused)1781 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1782 {
1783 	/* Firmware may have left a deferred SError in this register. */
1784 	write_sysreg_s(0, SYS_DISR_EL1);
1785 }
1786 #endif /* CONFIG_ARM64_RAS_EXTN */
1787 
1788 #ifdef CONFIG_ARM64_PTR_AUTH
has_address_auth_cpucap(const struct arm64_cpu_capabilities * entry,int scope)1789 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1790 {
1791 	int boot_val, sec_val;
1792 
1793 	/* We don't expect to be called with SCOPE_SYSTEM */
1794 	WARN_ON(scope == SCOPE_SYSTEM);
1795 	/*
1796 	 * The ptr-auth feature levels are not intercompatible with lower
1797 	 * levels. Hence we must match ptr-auth feature level of the secondary
1798 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1799 	 * from the sanitised register whereas direct register read is done for
1800 	 * the secondary CPUs.
1801 	 * The sanitised feature state is guaranteed to match that of the
1802 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1803 	 * a chance to update the state, with the capability.
1804 	 */
1805 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1806 					       entry->field_pos, entry->sign);
1807 	if (scope & SCOPE_BOOT_CPU)
1808 		return boot_val >= entry->min_field_value;
1809 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1810 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1811 					      entry->field_pos, entry->sign);
1812 	return sec_val == boot_val;
1813 }
1814 
has_address_auth_metacap(const struct arm64_cpu_capabilities * entry,int scope)1815 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1816 				     int scope)
1817 {
1818 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1819 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1820 }
1821 
has_generic_auth(const struct arm64_cpu_capabilities * entry,int __unused)1822 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1823 			     int __unused)
1824 {
1825 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1826 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1827 }
1828 #endif /* CONFIG_ARM64_PTR_AUTH */
1829 
1830 #ifdef CONFIG_ARM64_E0PD
cpu_enable_e0pd(struct arm64_cpu_capabilities const * cap)1831 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1832 {
1833 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1834 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1835 }
1836 #endif /* CONFIG_ARM64_E0PD */
1837 
1838 #ifdef CONFIG_ARM64_PSEUDO_NMI
1839 static bool enable_pseudo_nmi;
1840 
early_enable_pseudo_nmi(char * p)1841 static int __init early_enable_pseudo_nmi(char *p)
1842 {
1843 	return strtobool(p, &enable_pseudo_nmi);
1844 }
1845 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1846 
can_use_gic_priorities(const struct arm64_cpu_capabilities * entry,int scope)1847 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1848 				   int scope)
1849 {
1850 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1851 }
1852 #endif
1853 
1854 #ifdef CONFIG_ARM64_BTI
bti_enable(const struct arm64_cpu_capabilities * __unused)1855 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1856 {
1857 	/*
1858 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1859 	 * function entry points using BR is a requirement for
1860 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1861 	 * So, be strict and forbid other BRs using other registers to
1862 	 * jump onto a PACIxSP instruction:
1863 	 */
1864 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1865 	isb();
1866 }
1867 #endif /* CONFIG_ARM64_BTI */
1868 
1869 #ifdef CONFIG_ARM64_MTE
cpu_enable_mte(struct arm64_cpu_capabilities const * cap)1870 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1871 {
1872 	sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
1873 
1874 	mte_cpu_setup();
1875 
1876 	/*
1877 	 * Clear the tags in the zero page. This needs to be done via the
1878 	 * linear map which has the Tagged attribute.
1879 	 */
1880 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1881 		mte_clear_page_tags(lm_alias(empty_zero_page));
1882 
1883 	kasan_init_hw_tags_cpu();
1884 }
1885 #endif /* CONFIG_ARM64_MTE */
1886 
1887 #ifdef CONFIG_KVM
is_kvm_protected_mode(const struct arm64_cpu_capabilities * entry,int __unused)1888 static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
1889 {
1890 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
1891 		return false;
1892 
1893 	if (is_kernel_in_hyp_mode()) {
1894 		pr_warn("Protected KVM not available with VHE\n");
1895 		return false;
1896 	}
1897 
1898 	return true;
1899 }
1900 #endif /* CONFIG_KVM */
1901 
elf_hwcap_fixup(void)1902 static void elf_hwcap_fixup(void)
1903 {
1904 #ifdef CONFIG_ARM64_ERRATUM_1742098
1905 	if (cpus_have_const_cap(ARM64_WORKAROUND_1742098))
1906 		compat_elf_hwcap2 &= ~COMPAT_HWCAP2_AES;
1907 #endif /* ARM64_ERRATUM_1742098 */
1908 }
1909 
1910 /* Internal helper functions to match cpu capability type */
1911 static bool
cpucap_late_cpu_optional(const struct arm64_cpu_capabilities * cap)1912 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1913 {
1914 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1915 }
1916 
1917 static bool
cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities * cap)1918 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1919 {
1920 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1921 }
1922 
1923 static bool
cpucap_panic_on_conflict(const struct arm64_cpu_capabilities * cap)1924 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1925 {
1926 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1927 }
1928 
1929 static const struct arm64_cpu_capabilities arm64_features[] = {
1930 	{
1931 		.desc = "GIC system register CPU interface",
1932 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1933 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1934 		.matches = has_useable_gicv3_cpuif,
1935 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1936 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1937 		.sign = FTR_UNSIGNED,
1938 		.min_field_value = 1,
1939 	},
1940 #ifdef CONFIG_ARM64_PAN
1941 	{
1942 		.desc = "Privileged Access Never",
1943 		.capability = ARM64_HAS_PAN,
1944 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1945 		.matches = has_cpuid_feature,
1946 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1947 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1948 		.sign = FTR_UNSIGNED,
1949 		.min_field_value = 1,
1950 		.cpu_enable = cpu_enable_pan,
1951 	},
1952 #endif /* CONFIG_ARM64_PAN */
1953 #ifdef CONFIG_ARM64_LSE_ATOMICS
1954 	{
1955 		.desc = "LSE atomic instructions",
1956 		.capability = ARM64_HAS_LSE_ATOMICS,
1957 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1958 		.matches = has_cpuid_feature,
1959 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1960 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1961 		.sign = FTR_UNSIGNED,
1962 		.min_field_value = 2,
1963 	},
1964 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1965 	{
1966 		.desc = "Software prefetching using PRFM",
1967 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1968 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1969 		.matches = has_no_hw_prefetch,
1970 	},
1971 #ifdef CONFIG_ARM64_UAO
1972 	{
1973 		.desc = "User Access Override",
1974 		.capability = ARM64_HAS_UAO,
1975 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1976 		.matches = has_cpuid_feature,
1977 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1978 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
1979 		.min_field_value = 1,
1980 		/*
1981 		 * We rely on stop_machine() calling uao_thread_switch() to set
1982 		 * UAO immediately after patching.
1983 		 */
1984 	},
1985 #endif /* CONFIG_ARM64_UAO */
1986 #ifdef CONFIG_ARM64_PAN
1987 	{
1988 		.capability = ARM64_ALT_PAN_NOT_UAO,
1989 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1990 		.matches = cpufeature_pan_not_uao,
1991 	},
1992 #endif /* CONFIG_ARM64_PAN */
1993 #ifdef CONFIG_ARM64_VHE
1994 	{
1995 		.desc = "Virtualization Host Extensions",
1996 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1997 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1998 		.matches = runs_at_el2,
1999 		.cpu_enable = cpu_copy_el2regs,
2000 	},
2001 #endif	/* CONFIG_ARM64_VHE */
2002 	{
2003 		.capability = ARM64_HAS_32BIT_EL0_DO_NOT_USE,
2004 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2005 		.matches = has_32bit_el0,
2006 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2007 		.sign = FTR_UNSIGNED,
2008 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
2009 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
2010 	},
2011 #ifdef CONFIG_KVM
2012 	{
2013 		.desc = "32-bit EL1 Support",
2014 		.capability = ARM64_HAS_32BIT_EL1,
2015 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2016 		.matches = has_cpuid_feature,
2017 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2018 		.sign = FTR_UNSIGNED,
2019 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
2020 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
2021 	},
2022 	{
2023 		.desc = "Protected KVM",
2024 		.capability = ARM64_KVM_PROTECTED_MODE,
2025 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2026 		.matches = is_kvm_protected_mode,
2027 	},
2028 #endif
2029 	{
2030 		.desc = "Kernel page table isolation (KPTI)",
2031 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
2032 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2033 		/*
2034 		 * The ID feature fields below are used to indicate that
2035 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
2036 		 * more details.
2037 		 */
2038 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2039 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
2040 		.min_field_value = 1,
2041 		.matches = unmap_kernel_at_el0,
2042 		.cpu_enable = kpti_install_ng_mappings,
2043 	},
2044 	{
2045 		/* FP/SIMD is not implemented */
2046 		.capability = ARM64_HAS_NO_FPSIMD,
2047 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
2048 		.min_field_value = 0,
2049 		.matches = has_no_fpsimd,
2050 	},
2051 #ifdef CONFIG_ARM64_PMEM
2052 	{
2053 		.desc = "Data cache clean to Point of Persistence",
2054 		.capability = ARM64_HAS_DCPOP,
2055 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2056 		.matches = has_cpuid_feature,
2057 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2058 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2059 		.min_field_value = 1,
2060 	},
2061 	{
2062 		.desc = "Data cache clean to Point of Deep Persistence",
2063 		.capability = ARM64_HAS_DCPODP,
2064 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2065 		.matches = has_cpuid_feature,
2066 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2067 		.sign = FTR_UNSIGNED,
2068 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
2069 		.min_field_value = 2,
2070 	},
2071 #endif
2072 #ifdef CONFIG_ARM64_SVE
2073 	{
2074 		.desc = "Scalable Vector Extension",
2075 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2076 		.capability = ARM64_SVE,
2077 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2078 		.sign = FTR_UNSIGNED,
2079 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
2080 		.min_field_value = ID_AA64PFR0_SVE,
2081 		.matches = has_cpuid_feature,
2082 		.cpu_enable = sve_kernel_enable,
2083 	},
2084 #endif /* CONFIG_ARM64_SVE */
2085 #ifdef CONFIG_ARM64_RAS_EXTN
2086 	{
2087 		.desc = "RAS Extension Support",
2088 		.capability = ARM64_HAS_RAS_EXTN,
2089 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2090 		.matches = has_cpuid_feature,
2091 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2092 		.sign = FTR_UNSIGNED,
2093 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
2094 		.min_field_value = ID_AA64PFR0_RAS_V1,
2095 		.cpu_enable = cpu_clear_disr,
2096 	},
2097 #endif /* CONFIG_ARM64_RAS_EXTN */
2098 #ifdef CONFIG_ARM64_AMU_EXTN
2099 	{
2100 		/*
2101 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
2102 		 * Therefore, don't provide .desc as we don't want the detection
2103 		 * message to be shown until at least one CPU is detected to
2104 		 * support the feature.
2105 		 */
2106 		.capability = ARM64_HAS_AMU_EXTN,
2107 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2108 		.matches = has_amu,
2109 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2110 		.sign = FTR_UNSIGNED,
2111 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
2112 		.min_field_value = ID_AA64PFR0_AMU,
2113 		.cpu_enable = cpu_amu_enable,
2114 	},
2115 #endif /* CONFIG_ARM64_AMU_EXTN */
2116 	{
2117 		.desc = "Data cache clean to the PoU not required for I/D coherence",
2118 		.capability = ARM64_HAS_CACHE_IDC,
2119 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2120 		.matches = has_cache_idc,
2121 		.cpu_enable = cpu_emulate_effective_ctr,
2122 	},
2123 	{
2124 		.desc = "Instruction cache invalidation not required for I/D coherence",
2125 		.capability = ARM64_HAS_CACHE_DIC,
2126 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2127 		.matches = has_cache_dic,
2128 	},
2129 	{
2130 		.desc = "Stage-2 Force Write-Back",
2131 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2132 		.capability = ARM64_HAS_STAGE2_FWB,
2133 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2134 		.sign = FTR_UNSIGNED,
2135 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
2136 		.min_field_value = 1,
2137 		.matches = has_cpuid_feature,
2138 		.cpu_enable = cpu_has_fwb,
2139 	},
2140 	{
2141 		.desc = "ARMv8.4 Translation Table Level",
2142 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2143 		.capability = ARM64_HAS_ARMv8_4_TTL,
2144 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2145 		.sign = FTR_UNSIGNED,
2146 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
2147 		.min_field_value = 1,
2148 		.matches = has_cpuid_feature,
2149 	},
2150 	{
2151 		.desc = "TLB range maintenance instructions",
2152 		.capability = ARM64_HAS_TLB_RANGE,
2153 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2154 		.matches = has_cpuid_feature,
2155 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2156 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
2157 		.sign = FTR_UNSIGNED,
2158 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
2159 	},
2160 #ifdef CONFIG_ARM64_HW_AFDBM
2161 	{
2162 		/*
2163 		 * Since we turn this on always, we don't want the user to
2164 		 * think that the feature is available when it may not be.
2165 		 * So hide the description.
2166 		 *
2167 		 * .desc = "Hardware pagetable Dirty Bit Management",
2168 		 *
2169 		 */
2170 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
2171 		.capability = ARM64_HW_DBM,
2172 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2173 		.sign = FTR_UNSIGNED,
2174 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2175 		.min_field_value = 2,
2176 		.matches = has_hw_dbm,
2177 		.cpu_enable = cpu_enable_hw_dbm,
2178 	},
2179 #endif
2180 	{
2181 		.desc = "CRC32 instructions",
2182 		.capability = ARM64_HAS_CRC32,
2183 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2184 		.matches = has_cpuid_feature,
2185 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2186 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2187 		.min_field_value = 1,
2188 	},
2189 	{
2190 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2191 		.capability = ARM64_SSBS,
2192 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2193 		.matches = has_cpuid_feature,
2194 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2195 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2196 		.sign = FTR_UNSIGNED,
2197 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2198 	},
2199 #ifdef CONFIG_ARM64_CNP
2200 	{
2201 		.desc = "Common not Private translations",
2202 		.capability = ARM64_HAS_CNP,
2203 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2204 		.matches = has_useable_cnp,
2205 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2206 		.sign = FTR_UNSIGNED,
2207 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2208 		.min_field_value = 1,
2209 		.cpu_enable = cpu_enable_cnp,
2210 	},
2211 #endif
2212 	{
2213 		.desc = "Speculation barrier (SB)",
2214 		.capability = ARM64_HAS_SB,
2215 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2216 		.matches = has_cpuid_feature,
2217 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2218 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2219 		.sign = FTR_UNSIGNED,
2220 		.min_field_value = 1,
2221 	},
2222 #ifdef CONFIG_ARM64_PTR_AUTH
2223 	{
2224 		.desc = "Address authentication (architected algorithm)",
2225 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2226 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2227 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2228 		.sign = FTR_UNSIGNED,
2229 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2230 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2231 		.matches = has_address_auth_cpucap,
2232 	},
2233 	{
2234 		.desc = "Address authentication (IMP DEF algorithm)",
2235 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2236 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2237 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2238 		.sign = FTR_UNSIGNED,
2239 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2240 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2241 		.matches = has_address_auth_cpucap,
2242 	},
2243 	{
2244 		.capability = ARM64_HAS_ADDRESS_AUTH,
2245 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2246 		.matches = has_address_auth_metacap,
2247 	},
2248 	{
2249 		.desc = "Generic authentication (architected algorithm)",
2250 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2251 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2252 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2253 		.sign = FTR_UNSIGNED,
2254 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2255 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2256 		.matches = has_cpuid_feature,
2257 	},
2258 	{
2259 		.desc = "Generic authentication (IMP DEF algorithm)",
2260 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2261 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2262 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2263 		.sign = FTR_UNSIGNED,
2264 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2265 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2266 		.matches = has_cpuid_feature,
2267 	},
2268 	{
2269 		.capability = ARM64_HAS_GENERIC_AUTH,
2270 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2271 		.matches = has_generic_auth,
2272 	},
2273 #endif /* CONFIG_ARM64_PTR_AUTH */
2274 #ifdef CONFIG_ARM64_PSEUDO_NMI
2275 	{
2276 		/*
2277 		 * Depends on having GICv3
2278 		 */
2279 		.desc = "IRQ priority masking",
2280 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2281 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2282 		.matches = can_use_gic_priorities,
2283 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2284 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2285 		.sign = FTR_UNSIGNED,
2286 		.min_field_value = 1,
2287 	},
2288 #endif
2289 #ifdef CONFIG_ARM64_E0PD
2290 	{
2291 		.desc = "E0PD",
2292 		.capability = ARM64_HAS_E0PD,
2293 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2294 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2295 		.sign = FTR_UNSIGNED,
2296 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2297 		.matches = has_cpuid_feature,
2298 		.min_field_value = 1,
2299 		.cpu_enable = cpu_enable_e0pd,
2300 	},
2301 #endif
2302 #ifdef CONFIG_ARCH_RANDOM
2303 	{
2304 		.desc = "Random Number Generator",
2305 		.capability = ARM64_HAS_RNG,
2306 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2307 		.matches = has_cpuid_feature,
2308 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2309 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2310 		.sign = FTR_UNSIGNED,
2311 		.min_field_value = 1,
2312 	},
2313 #endif
2314 #ifdef CONFIG_ARM64_BTI
2315 	{
2316 		.desc = "Branch Target Identification",
2317 		.capability = ARM64_BTI,
2318 #ifdef CONFIG_ARM64_BTI_KERNEL
2319 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2320 #else
2321 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2322 #endif
2323 		.matches = has_cpuid_feature,
2324 		.cpu_enable = bti_enable,
2325 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2326 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2327 		.min_field_value = ID_AA64PFR1_BT_BTI,
2328 		.sign = FTR_UNSIGNED,
2329 	},
2330 #endif
2331 #ifdef CONFIG_ARM64_MTE
2332 	{
2333 		.desc = "Memory Tagging Extension",
2334 		.capability = ARM64_MTE,
2335 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2336 		.matches = has_cpuid_feature,
2337 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2338 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2339 		.min_field_value = ID_AA64PFR1_MTE,
2340 		.sign = FTR_UNSIGNED,
2341 		.cpu_enable = cpu_enable_mte,
2342 	},
2343 #endif /* CONFIG_ARM64_MTE */
2344 	{
2345 		.desc = "RCpc load-acquire (LDAPR)",
2346 		.capability = ARM64_HAS_LDAPR,
2347 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2348 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2349 		.sign = FTR_UNSIGNED,
2350 		.field_pos = ID_AA64ISAR1_LRCPC_SHIFT,
2351 		.matches = has_cpuid_feature,
2352 		.min_field_value = 1,
2353 	},
2354 	{},
2355 };
2356 
2357 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2358 		.matches = has_cpuid_feature,					\
2359 		.sys_reg = reg,							\
2360 		.field_pos = field,						\
2361 		.sign = s,							\
2362 		.min_field_value = min_value,
2363 
2364 #define __HWCAP_CAP(name, cap_type, cap)					\
2365 		.desc = name,							\
2366 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2367 		.hwcap_type = cap_type,						\
2368 		.hwcap = cap,							\
2369 
2370 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2371 	{									\
2372 		__HWCAP_CAP(#cap, cap_type, cap)				\
2373 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2374 	}
2375 
2376 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2377 	{									\
2378 		__HWCAP_CAP(#cap, cap_type, cap)				\
2379 		.matches = cpucap_multi_entry_cap_matches,			\
2380 		.match_list = list,						\
2381 	}
2382 
2383 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2384 	{									\
2385 		__HWCAP_CAP(#cap, cap_type, cap)				\
2386 		.matches = match,						\
2387 	}
2388 
2389 #ifdef CONFIG_ARM64_PTR_AUTH
2390 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2391 	{
2392 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2393 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2394 	},
2395 	{
2396 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2397 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2398 	},
2399 	{},
2400 };
2401 
2402 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2403 	{
2404 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2405 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2406 	},
2407 	{
2408 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2409 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2410 	},
2411 	{},
2412 };
2413 #endif
2414 
2415 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2416 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2417 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2418 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2419 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2420 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2421 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2422 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2423 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2424 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2425 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2426 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2427 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2428 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2429 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2430 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2431 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2432 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2433 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2434 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2435 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2436 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2437 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2438 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2439 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2440 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2441 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2442 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2443 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2444 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2445 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2446 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2447 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2448 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2449 #ifdef CONFIG_ARM64_SVE
2450 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2451 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2452 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2453 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2454 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2455 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2456 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2457 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2458 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2459 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2460 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2461 #endif
2462 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2463 #ifdef CONFIG_ARM64_BTI
2464 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2465 #endif
2466 #ifdef CONFIG_ARM64_PTR_AUTH
2467 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2468 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2469 #endif
2470 #ifdef CONFIG_ARM64_MTE
2471 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2472 #endif /* CONFIG_ARM64_MTE */
2473 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2474 	HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
2475 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2476 	{},
2477 };
2478 
2479 #ifdef CONFIG_COMPAT
compat_has_neon(const struct arm64_cpu_capabilities * cap,int scope)2480 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2481 {
2482 	/*
2483 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2484 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2485 	 * check is future proof, by making sure value is non-zero.
2486 	 */
2487 	u32 mvfr1;
2488 
2489 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2490 	if (scope == SCOPE_SYSTEM)
2491 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2492 	else
2493 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2494 
2495 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2496 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2497 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2498 }
2499 #endif
2500 
2501 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2502 #ifdef CONFIG_COMPAT
2503 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2504 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2505 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2506 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2507 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2508 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2509 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2510 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2511 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2512 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2513 #endif
2514 	{},
2515 };
2516 
cap_set_elf_hwcap(const struct arm64_cpu_capabilities * cap)2517 static void cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2518 {
2519 	switch (cap->hwcap_type) {
2520 	case CAP_HWCAP:
2521 		cpu_set_feature(cap->hwcap);
2522 		break;
2523 #ifdef CONFIG_COMPAT
2524 	case CAP_COMPAT_HWCAP:
2525 		compat_elf_hwcap |= (u32)cap->hwcap;
2526 		break;
2527 	case CAP_COMPAT_HWCAP2:
2528 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2529 		break;
2530 #endif
2531 	default:
2532 		WARN_ON(1);
2533 		break;
2534 	}
2535 }
2536 
2537 /* Check if we have a particular HWCAP enabled */
cpus_have_elf_hwcap(const struct arm64_cpu_capabilities * cap)2538 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2539 {
2540 	bool rc;
2541 
2542 	switch (cap->hwcap_type) {
2543 	case CAP_HWCAP:
2544 		rc = cpu_have_feature(cap->hwcap);
2545 		break;
2546 #ifdef CONFIG_COMPAT
2547 	case CAP_COMPAT_HWCAP:
2548 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2549 		break;
2550 	case CAP_COMPAT_HWCAP2:
2551 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2552 		break;
2553 #endif
2554 	default:
2555 		WARN_ON(1);
2556 		rc = false;
2557 	}
2558 
2559 	return rc;
2560 }
2561 
setup_elf_hwcaps(const struct arm64_cpu_capabilities * hwcaps)2562 static void setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2563 {
2564 	/* We support emulation of accesses to CPU ID feature registers */
2565 	cpu_set_named_feature(CPUID);
2566 	for (; hwcaps->matches; hwcaps++)
2567 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2568 			cap_set_elf_hwcap(hwcaps);
2569 }
2570 
update_cpu_capabilities(u16 scope_mask)2571 static void update_cpu_capabilities(u16 scope_mask)
2572 {
2573 	int i;
2574 	const struct arm64_cpu_capabilities *caps;
2575 
2576 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2577 	for (i = 0; i < ARM64_NCAPS; i++) {
2578 		caps = cpu_hwcaps_ptrs[i];
2579 		if (!caps || !(caps->type & scope_mask) ||
2580 		    cpus_have_cap(caps->capability) ||
2581 		    !caps->matches(caps, cpucap_default_scope(caps)))
2582 			continue;
2583 
2584 		if (caps->desc)
2585 			pr_info("detected: %s\n", caps->desc);
2586 		cpus_set_cap(caps->capability);
2587 
2588 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2589 			set_bit(caps->capability, boot_capabilities);
2590 	}
2591 }
2592 
2593 /*
2594  * Enable all the available capabilities on this CPU. The capabilities
2595  * with BOOT_CPU scope are handled separately and hence skipped here.
2596  */
cpu_enable_non_boot_scope_capabilities(void * __unused)2597 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2598 {
2599 	int i;
2600 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2601 
2602 	for_each_available_cap(i) {
2603 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2604 
2605 		if (WARN_ON(!cap))
2606 			continue;
2607 
2608 		if (!(cap->type & non_boot_scope))
2609 			continue;
2610 
2611 		if (cap->cpu_enable)
2612 			cap->cpu_enable(cap);
2613 	}
2614 	return 0;
2615 }
2616 
2617 /*
2618  * Run through the enabled capabilities and enable() it on all active
2619  * CPUs
2620  */
enable_cpu_capabilities(u16 scope_mask)2621 static void __init enable_cpu_capabilities(u16 scope_mask)
2622 {
2623 	int i;
2624 	const struct arm64_cpu_capabilities *caps;
2625 	bool boot_scope;
2626 
2627 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2628 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2629 
2630 	for (i = 0; i < ARM64_NCAPS; i++) {
2631 		unsigned int num;
2632 
2633 		caps = cpu_hwcaps_ptrs[i];
2634 		if (!caps || !(caps->type & scope_mask))
2635 			continue;
2636 		num = caps->capability;
2637 		if (!cpus_have_cap(num))
2638 			continue;
2639 
2640 		/* Ensure cpus_have_const_cap(num) works */
2641 		static_branch_enable(&cpu_hwcap_keys[num]);
2642 
2643 		if (boot_scope && caps->cpu_enable)
2644 			/*
2645 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2646 			 * before any secondary CPU boots. Thus, each secondary
2647 			 * will enable the capability as appropriate via
2648 			 * check_local_cpu_capabilities(). The only exception is
2649 			 * the boot CPU, for which the capability must be
2650 			 * enabled here. This approach avoids costly
2651 			 * stop_machine() calls for this case.
2652 			 */
2653 			caps->cpu_enable(caps);
2654 	}
2655 
2656 	/*
2657 	 * For all non-boot scope capabilities, use stop_machine()
2658 	 * as it schedules the work allowing us to modify PSTATE,
2659 	 * instead of on_each_cpu() which uses an IPI, giving us a
2660 	 * PSTATE that disappears when we return.
2661 	 */
2662 	if (!boot_scope)
2663 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2664 			     NULL, cpu_online_mask);
2665 }
2666 
2667 /*
2668  * Run through the list of capabilities to check for conflicts.
2669  * If the system has already detected a capability, take necessary
2670  * action on this CPU.
2671  */
verify_local_cpu_caps(u16 scope_mask)2672 static void verify_local_cpu_caps(u16 scope_mask)
2673 {
2674 	int i;
2675 	bool cpu_has_cap, system_has_cap;
2676 	const struct arm64_cpu_capabilities *caps;
2677 
2678 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2679 
2680 	for (i = 0; i < ARM64_NCAPS; i++) {
2681 		caps = cpu_hwcaps_ptrs[i];
2682 		if (!caps || !(caps->type & scope_mask))
2683 			continue;
2684 
2685 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2686 		system_has_cap = cpus_have_cap(caps->capability);
2687 
2688 		if (system_has_cap) {
2689 			/*
2690 			 * Check if the new CPU misses an advertised feature,
2691 			 * which is not safe to miss.
2692 			 */
2693 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2694 				break;
2695 			/*
2696 			 * We have to issue cpu_enable() irrespective of
2697 			 * whether the CPU has it or not, as it is enabeld
2698 			 * system wide. It is upto the call back to take
2699 			 * appropriate action on this CPU.
2700 			 */
2701 			if (caps->cpu_enable)
2702 				caps->cpu_enable(caps);
2703 		} else {
2704 			/*
2705 			 * Check if the CPU has this capability if it isn't
2706 			 * safe to have when the system doesn't.
2707 			 */
2708 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2709 				break;
2710 		}
2711 	}
2712 
2713 	if (i < ARM64_NCAPS) {
2714 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2715 			smp_processor_id(), caps->capability,
2716 			caps->desc, system_has_cap, cpu_has_cap);
2717 
2718 		if (cpucap_panic_on_conflict(caps))
2719 			cpu_panic_kernel();
2720 		else
2721 			cpu_die_early();
2722 	}
2723 }
2724 
2725 /*
2726  * Check for CPU features that are used in early boot
2727  * based on the Boot CPU value.
2728  */
check_early_cpu_features(void)2729 static void check_early_cpu_features(void)
2730 {
2731 	verify_cpu_asid_bits();
2732 
2733 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2734 }
2735 
2736 static void
__verify_local_elf_hwcaps(const struct arm64_cpu_capabilities * caps)2737 __verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2738 {
2739 
2740 	for (; caps->matches; caps++)
2741 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2742 			pr_crit("CPU%d: missing HWCAP: %s\n",
2743 					smp_processor_id(), caps->desc);
2744 			cpu_die_early();
2745 		}
2746 }
2747 
verify_local_elf_hwcaps(void)2748 static void verify_local_elf_hwcaps(void)
2749 {
2750 	__verify_local_elf_hwcaps(arm64_elf_hwcaps);
2751 
2752 	if (id_aa64pfr0_32bit_el0(read_cpuid(ID_AA64PFR0_EL1)))
2753 		__verify_local_elf_hwcaps(compat_elf_hwcaps);
2754 }
2755 
verify_sve_features(void)2756 static void verify_sve_features(void)
2757 {
2758 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2759 	u64 zcr = read_zcr_features();
2760 
2761 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2762 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2763 
2764 	if (len < safe_len || sve_verify_vq_map()) {
2765 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2766 			smp_processor_id());
2767 		cpu_die_early();
2768 	}
2769 
2770 	/* Add checks on other ZCR bits here if necessary */
2771 }
2772 
verify_hyp_capabilities(void)2773 static void verify_hyp_capabilities(void)
2774 {
2775 	u64 safe_mmfr1, mmfr0, mmfr1;
2776 	int parange, ipa_max;
2777 	unsigned int safe_vmid_bits, vmid_bits;
2778 
2779 	if (!IS_ENABLED(CONFIG_KVM))
2780 		return;
2781 
2782 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2783 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2784 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2785 
2786 	/* Verify VMID bits */
2787 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2788 	vmid_bits = get_vmid_bits(mmfr1);
2789 	if (vmid_bits < safe_vmid_bits) {
2790 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2791 		cpu_die_early();
2792 	}
2793 
2794 	/* Verify IPA range */
2795 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2796 				ID_AA64MMFR0_PARANGE_SHIFT);
2797 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2798 	if (ipa_max < get_kvm_ipa_limit()) {
2799 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2800 		cpu_die_early();
2801 	}
2802 }
2803 
2804 /*
2805  * Run through the enabled system capabilities and enable() it on this CPU.
2806  * The capabilities were decided based on the available CPUs at the boot time.
2807  * Any new CPU should match the system wide status of the capability. If the
2808  * new CPU doesn't have a capability which the system now has enabled, we
2809  * cannot do anything to fix it up and could cause unexpected failures. So
2810  * we park the CPU.
2811  */
verify_local_cpu_capabilities(void)2812 static void verify_local_cpu_capabilities(void)
2813 {
2814 	/*
2815 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2816 	 * check_early_cpu_features(), as they need to be verified
2817 	 * on all secondary CPUs.
2818 	 */
2819 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2820 	verify_local_elf_hwcaps();
2821 
2822 	if (system_supports_sve())
2823 		verify_sve_features();
2824 
2825 	if (is_hyp_mode_available())
2826 		verify_hyp_capabilities();
2827 }
2828 
check_local_cpu_capabilities(void)2829 void check_local_cpu_capabilities(void)
2830 {
2831 	/*
2832 	 * All secondary CPUs should conform to the early CPU features
2833 	 * in use by the kernel based on boot CPU.
2834 	 */
2835 	check_early_cpu_features();
2836 
2837 	/*
2838 	 * If we haven't finalised the system capabilities, this CPU gets
2839 	 * a chance to update the errata work arounds and local features.
2840 	 * Otherwise, this CPU should verify that it has all the system
2841 	 * advertised capabilities.
2842 	 */
2843 	if (!system_capabilities_finalized())
2844 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2845 	else
2846 		verify_local_cpu_capabilities();
2847 }
2848 
setup_boot_cpu_capabilities(void)2849 static void __init setup_boot_cpu_capabilities(void)
2850 {
2851 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2852 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2853 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2854 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2855 }
2856 
this_cpu_has_cap(unsigned int n)2857 bool this_cpu_has_cap(unsigned int n)
2858 {
2859 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2860 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2861 
2862 		if (cap)
2863 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2864 	}
2865 
2866 	return false;
2867 }
2868 
2869 /*
2870  * This helper function is used in a narrow window when,
2871  * - The system wide safe registers are set with all the SMP CPUs and,
2872  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2873  * In all other cases cpus_have_{const_}cap() should be used.
2874  */
__system_matches_cap(unsigned int n)2875 static bool __system_matches_cap(unsigned int n)
2876 {
2877 	if (n < ARM64_NCAPS) {
2878 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2879 
2880 		if (cap)
2881 			return cap->matches(cap, SCOPE_SYSTEM);
2882 	}
2883 	return false;
2884 }
2885 
cpu_set_feature(unsigned int num)2886 void cpu_set_feature(unsigned int num)
2887 {
2888 	WARN_ON(num >= MAX_CPU_FEATURES);
2889 	elf_hwcap |= BIT(num);
2890 }
2891 EXPORT_SYMBOL_GPL(cpu_set_feature);
2892 
cpu_have_feature(unsigned int num)2893 bool cpu_have_feature(unsigned int num)
2894 {
2895 	WARN_ON(num >= MAX_CPU_FEATURES);
2896 	return elf_hwcap & BIT(num);
2897 }
2898 EXPORT_SYMBOL_GPL(cpu_have_feature);
2899 
cpu_get_elf_hwcap(void)2900 unsigned long cpu_get_elf_hwcap(void)
2901 {
2902 	/*
2903 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2904 	 * note that for userspace compatibility we guarantee that bits 62
2905 	 * and 63 will always be returned as 0.
2906 	 */
2907 	return lower_32_bits(elf_hwcap);
2908 }
2909 
cpu_get_elf_hwcap2(void)2910 unsigned long cpu_get_elf_hwcap2(void)
2911 {
2912 	return upper_32_bits(elf_hwcap);
2913 }
2914 
setup_system_capabilities(void)2915 static void __init setup_system_capabilities(void)
2916 {
2917 	/*
2918 	 * We have finalised the system-wide safe feature
2919 	 * registers, finalise the capabilities that depend
2920 	 * on it. Also enable all the available capabilities,
2921 	 * that are not enabled already.
2922 	 */
2923 	update_cpu_capabilities(SCOPE_SYSTEM);
2924 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2925 }
2926 
setup_cpu_features(void)2927 void __init setup_cpu_features(void)
2928 {
2929 	u32 cwg;
2930 
2931 	setup_system_capabilities();
2932 	setup_elf_hwcaps(arm64_elf_hwcaps);
2933 
2934 	if (system_supports_32bit_el0()) {
2935 		setup_elf_hwcaps(compat_elf_hwcaps);
2936 		elf_hwcap_fixup();
2937 	}
2938 
2939 	if (system_uses_ttbr0_pan())
2940 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2941 
2942 	sve_setup();
2943 	minsigstksz_setup();
2944 
2945 	/* Advertise that we have computed the system capabilities */
2946 	finalize_system_capabilities();
2947 
2948 	/*
2949 	 * Check for sane CTR_EL0.CWG value.
2950 	 */
2951 	cwg = cache_type_cwg();
2952 	if (!cwg)
2953 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2954 			ARCH_DMA_MINALIGN);
2955 }
2956 
enable_mismatched_32bit_el0(unsigned int cpu)2957 static int enable_mismatched_32bit_el0(unsigned int cpu)
2958 {
2959 	static int lucky_winner = -1;
2960 
2961 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu);
2962 	bool cpu_32bit = id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0);
2963 
2964 	if (cpu_32bit) {
2965 		cpumask_set_cpu(cpu, cpu_32bit_el0_mask);
2966 		static_branch_enable_cpuslocked(&arm64_mismatched_32bit_el0);
2967 	}
2968 
2969 	if (cpumask_test_cpu(0, cpu_32bit_el0_mask) == cpu_32bit)
2970 		return 0;
2971 
2972 	if (lucky_winner >= 0)
2973 		return 0;
2974 
2975 	/*
2976 	 * We've detected a mismatch. We need to keep one of our CPUs with
2977 	 * 32-bit EL0 online so that is_cpu_allowed() doesn't end up rejecting
2978 	 * every CPU in the system for a 32-bit task.
2979 	 */
2980 	lucky_winner = cpu_32bit ? cpu : cpumask_any_and(cpu_32bit_el0_mask,
2981 							 cpu_active_mask);
2982 	get_cpu_device(lucky_winner)->offline_disabled = true;
2983 	setup_elf_hwcaps(compat_elf_hwcaps);
2984 	pr_info("Asymmetric 32-bit EL0 support detected on CPU %u; CPU hot-unplug disabled on CPU %u\n",
2985 		cpu, lucky_winner);
2986 	return 0;
2987 }
2988 
init_32bit_el0_mask(void)2989 static int __init init_32bit_el0_mask(void)
2990 {
2991 	if (!allow_mismatched_32bit_el0)
2992 		return 0;
2993 
2994 	if (!zalloc_cpumask_var(&cpu_32bit_el0_mask, GFP_KERNEL))
2995 		return -ENOMEM;
2996 
2997 	return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
2998 				 "arm64/mismatched_32bit_el0:online",
2999 				 enable_mismatched_32bit_el0, NULL);
3000 }
3001 subsys_initcall_sync(init_32bit_el0_mask);
3002 
3003 static bool __maybe_unused
cpufeature_pan_not_uao(const struct arm64_cpu_capabilities * entry,int __unused)3004 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
3005 {
3006 	return (__system_matches_cap(ARM64_HAS_PAN) && !__system_matches_cap(ARM64_HAS_UAO));
3007 }
3008 
cpu_enable_cnp(struct arm64_cpu_capabilities const * cap)3009 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
3010 {
3011 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
3012 }
3013 
3014 /*
3015  * We emulate only the following system register space.
3016  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
3017  * See Table C5-6 System instruction encodings for System register accesses,
3018  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
3019  */
is_emulated(u32 id)3020 static inline bool __attribute_const__ is_emulated(u32 id)
3021 {
3022 	return (sys_reg_Op0(id) == 0x3 &&
3023 		sys_reg_CRn(id) == 0x0 &&
3024 		sys_reg_Op1(id) == 0x0 &&
3025 		(sys_reg_CRm(id) == 0 ||
3026 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
3027 }
3028 
3029 /*
3030  * With CRm == 0, reg should be one of :
3031  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
3032  */
emulate_id_reg(u32 id,u64 * valp)3033 static inline int emulate_id_reg(u32 id, u64 *valp)
3034 {
3035 	switch (id) {
3036 	case SYS_MIDR_EL1:
3037 		*valp = read_cpuid_id();
3038 		break;
3039 	case SYS_MPIDR_EL1:
3040 		*valp = SYS_MPIDR_SAFE_VAL;
3041 		break;
3042 	case SYS_REVIDR_EL1:
3043 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
3044 		*valp = 0;
3045 		break;
3046 	default:
3047 		return -EINVAL;
3048 	}
3049 
3050 	return 0;
3051 }
3052 
emulate_sys_reg(u32 id,u64 * valp)3053 static int emulate_sys_reg(u32 id, u64 *valp)
3054 {
3055 	struct arm64_ftr_reg *regp;
3056 
3057 	if (!is_emulated(id))
3058 		return -EINVAL;
3059 
3060 	if (sys_reg_CRm(id) == 0)
3061 		return emulate_id_reg(id, valp);
3062 
3063 	regp = get_arm64_ftr_reg_nowarn(id);
3064 	if (regp)
3065 		*valp = arm64_ftr_reg_user_value(regp);
3066 	else
3067 		/*
3068 		 * The untracked registers are either IMPLEMENTATION DEFINED
3069 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
3070 		 */
3071 		*valp = 0;
3072 	return 0;
3073 }
3074 
do_emulate_mrs(struct pt_regs * regs,u32 sys_reg,u32 rt)3075 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
3076 {
3077 	int rc;
3078 	u64 val;
3079 
3080 	rc = emulate_sys_reg(sys_reg, &val);
3081 	if (!rc) {
3082 		pt_regs_write_reg(regs, rt, val);
3083 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
3084 	}
3085 	return rc;
3086 }
3087 
emulate_mrs(struct pt_regs * regs,u32 insn)3088 static int emulate_mrs(struct pt_regs *regs, u32 insn)
3089 {
3090 	u32 sys_reg, rt;
3091 
3092 	/*
3093 	 * sys_reg values are defined as used in mrs/msr instruction.
3094 	 * shift the imm value to get the encoding.
3095 	 */
3096 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
3097 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
3098 	return do_emulate_mrs(regs, sys_reg, rt);
3099 }
3100 
3101 static struct undef_hook mrs_hook = {
3102 	.instr_mask = 0xfff00000,
3103 	.instr_val  = 0xd5300000,
3104 	.pstate_mask = PSR_AA32_MODE_MASK,
3105 	.pstate_val = PSR_MODE_EL0t,
3106 	.fn = emulate_mrs,
3107 };
3108 
enable_mrs_emulation(void)3109 static int __init enable_mrs_emulation(void)
3110 {
3111 	register_undef_hook(&mrs_hook);
3112 	return 0;
3113 }
3114 
3115 core_initcall(enable_mrs_emulation);
3116 
arm64_get_meltdown_state(void)3117 enum mitigation_state arm64_get_meltdown_state(void)
3118 {
3119 	if (__meltdown_safe)
3120 		return SPECTRE_UNAFFECTED;
3121 
3122 	if (arm64_kernel_unmapped_at_el0())
3123 		return SPECTRE_MITIGATED;
3124 
3125 	return SPECTRE_VULNERABLE;
3126 }
3127 
cpu_show_meltdown(struct device * dev,struct device_attribute * attr,char * buf)3128 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
3129 			  char *buf)
3130 {
3131 	switch (arm64_get_meltdown_state()) {
3132 	case SPECTRE_UNAFFECTED:
3133 		return sprintf(buf, "Not affected\n");
3134 
3135 	case SPECTRE_MITIGATED:
3136 		return sprintf(buf, "Mitigation: PTI\n");
3137 
3138 	default:
3139 		return sprintf(buf, "Vulnerable\n");
3140 	}
3141 }
3142