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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/types.h>
72 #include <linux/mm.h>
73 #include <linux/cpu.h>
74 
75 #include <asm/cpu.h>
76 #include <asm/cpufeature.h>
77 #include <asm/cpu_ops.h>
78 #include <asm/fpsimd.h>
79 #include <asm/mmu_context.h>
80 #include <asm/mte.h>
81 #include <asm/processor.h>
82 #include <asm/sysreg.h>
83 #include <asm/traps.h>
84 #include <asm/vectors.h>
85 #include <asm/virt.h>
86 
87 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
88 static unsigned long elf_hwcap __read_mostly;
89 
90 #ifdef CONFIG_COMPAT
91 #define COMPAT_ELF_HWCAP_DEFAULT	\
92 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
93 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
94 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
95 				 COMPAT_HWCAP_LPAE)
96 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
97 unsigned int compat_elf_hwcap2 __read_mostly;
98 #endif
99 
100 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
101 EXPORT_SYMBOL(cpu_hwcaps);
102 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
103 
104 /* Need also bit for ARM64_CB_PATCH */
105 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
106 
107 bool arm64_use_ng_mappings = false;
108 EXPORT_SYMBOL(arm64_use_ng_mappings);
109 
110 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
111 
112 /*
113  * Flag to indicate if we have computed the system wide
114  * capabilities based on the boot time active CPUs. This
115  * will be used to determine if a new booting CPU should
116  * go through the verification process to make sure that it
117  * supports the system capabilities, without using a hotplug
118  * notifier. This is also used to decide if we could use
119  * the fast path for checking constant CPU caps.
120  */
121 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
122 EXPORT_SYMBOL(arm64_const_caps_ready);
finalize_system_capabilities(void)123 static inline void finalize_system_capabilities(void)
124 {
125 	static_branch_enable(&arm64_const_caps_ready);
126 }
127 
dump_cpu_features(void)128 void dump_cpu_features(void)
129 {
130 	/* file-wide pr_fmt adds "CPU features: " prefix */
131 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
132 }
133 
134 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
135 EXPORT_SYMBOL(cpu_hwcap_keys);
136 
137 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
138 	{						\
139 		.sign = SIGNED,				\
140 		.visible = VISIBLE,			\
141 		.strict = STRICT,			\
142 		.type = TYPE,				\
143 		.shift = SHIFT,				\
144 		.width = WIDTH,				\
145 		.safe_val = SAFE_VAL,			\
146 	}
147 
148 /* Define a feature with unsigned values */
149 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
150 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
151 
152 /* Define a feature with a signed value */
153 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
154 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
155 
156 #define ARM64_FTR_END					\
157 	{						\
158 		.width = 0,				\
159 	}
160 
161 /* meta feature for alternatives */
162 static bool __maybe_unused
163 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
164 
165 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
166 
167 static bool __system_matches_cap(unsigned int n);
168 
169 /*
170  * NOTE: Any changes to the visibility of features should be kept in
171  * sync with the documentation of the CPU feature register ABI.
172  */
173 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
174 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
175 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
176 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
178 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
179 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
180 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
181 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
182 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
183 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
184 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
187 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
188 	ARM64_FTR_END,
189 };
190 
191 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
192 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
199 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
200 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
201 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
202 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
206 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
207 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
208 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
209 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
210 	ARM64_FTR_END,
211 };
212 
213 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
214 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
215 	ARM64_FTR_END,
216 };
217 
218 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
219 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
220 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
221 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
223 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
226 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
228 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
229 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
230 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
231 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
232 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
233 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
235 	ARM64_FTR_END,
236 };
237 
238 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
239 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
240 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
241 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
242 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
243 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
244 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
245 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
246 	ARM64_FTR_END,
247 };
248 
249 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
250 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
251 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
252 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
253 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
254 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
255 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
256 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
257 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
258 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
259 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
260 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
261 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
263 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
264 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
265 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
266 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
267 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
268 	ARM64_FTR_END,
269 };
270 
271 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
272 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
273 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
274 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
275 	/*
276 	 * Page size not being supported at Stage-2 is not fatal. You
277 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
278 	 * your favourite nesting hypervisor.
279 	 *
280 	 * There is a small corner case where the hypervisor explicitly
281 	 * advertises a given granule size at Stage-2 (value 2) on some
282 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
283 	 * vCPUs. Although this is not forbidden by the architecture, it
284 	 * indicates that the hypervisor is being silly (or buggy).
285 	 *
286 	 * We make no effort to cope with this and pretend that if these
287 	 * fields are inconsistent across vCPUs, then it isn't worth
288 	 * trying to bring KVM up.
289 	 */
290 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
291 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
292 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
293 	/*
294 	 * We already refuse to boot CPUs that don't support our configured
295 	 * page size, so we can only detect mismatches for a page size other
296 	 * than the one we're currently using. Unfortunately, SoCs like this
297 	 * exist in the wild so, even though we don't like it, we'll have to go
298 	 * along with it and treat them as non-strict.
299 	 */
300 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
301 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
302 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
303 
304 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
305 	/* Linux shouldn't care about secure memory */
306 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
307 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
308 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
309 	/*
310 	 * Differing PARange is fine as long as all peripherals and memory are mapped
311 	 * within the minimum PARange of all CPUs
312 	 */
313 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
314 	ARM64_FTR_END,
315 };
316 
317 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
318 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
319 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
320 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
324 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
326 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
328 	ARM64_FTR_END,
329 };
330 
331 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
332 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
333 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
334 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
335 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
338 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
347 	ARM64_FTR_END,
348 };
349 
350 static const struct arm64_ftr_bits ftr_ctr[] = {
351 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
352 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
353 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
354 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
355 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
356 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
357 	/*
358 	 * Linux can handle differing I-cache policies. Userspace JITs will
359 	 * make use of *minLine.
360 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
361 	 */
362 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
363 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
364 	ARM64_FTR_END,
365 };
366 
367 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
368 	.name		= "SYS_CTR_EL0",
369 	.ftr_bits	= ftr_ctr
370 };
371 
372 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
373 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
374 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
375 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
376 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
377 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
378 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
379 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
380 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
381 	ARM64_FTR_END,
382 };
383 
384 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
385 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
386 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
387 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
388 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
390 	/*
391 	 * We can instantiate multiple PMU instances with different levels
392 	 * of support.
393 	 */
394 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
395 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
396 	ARM64_FTR_END,
397 };
398 
399 static const struct arm64_ftr_bits ftr_mvfr2[] = {
400 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
401 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
402 	ARM64_FTR_END,
403 };
404 
405 static const struct arm64_ftr_bits ftr_dczid[] = {
406 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
407 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
408 	ARM64_FTR_END,
409 };
410 
411 static const struct arm64_ftr_bits ftr_id_isar0[] = {
412 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
413 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
414 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
415 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
416 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
417 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
418 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
419 	ARM64_FTR_END,
420 };
421 
422 static const struct arm64_ftr_bits ftr_id_isar5[] = {
423 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
424 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
425 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
427 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
428 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
429 	ARM64_FTR_END,
430 };
431 
432 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
433 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
434 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
435 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
436 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
440 
441 	/*
442 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
443 	 * external abort on speculative read. It is safe to assume that an
444 	 * SError might be generated than it will not be. Hence it has been
445 	 * classified as FTR_HIGHER_SAFE.
446 	 */
447 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
448 	ARM64_FTR_END,
449 };
450 
451 static const struct arm64_ftr_bits ftr_id_isar4[] = {
452 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
453 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
454 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
459 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
460 	ARM64_FTR_END,
461 };
462 
463 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
464 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
465 	ARM64_FTR_END,
466 };
467 
468 static const struct arm64_ftr_bits ftr_id_isar6[] = {
469 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
470 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
471 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
473 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
474 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
475 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
476 	ARM64_FTR_END,
477 };
478 
479 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
480 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
481 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
482 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
484 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
485 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
486 	ARM64_FTR_END,
487 };
488 
489 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
490 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
491 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
492 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
495 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
496 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
498 	ARM64_FTR_END,
499 };
500 
501 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
502 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
503 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
504 	ARM64_FTR_END,
505 };
506 
507 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
508 	/* [31:28] TraceFilt */
509 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_PERFMON_SHIFT, 4, 0xf),
510 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
511 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
512 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
516 	ARM64_FTR_END,
517 };
518 
519 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
520 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
521 	ARM64_FTR_END,
522 };
523 
524 static const struct arm64_ftr_bits ftr_zcr[] = {
525 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
526 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
527 	ARM64_FTR_END,
528 };
529 
530 /*
531  * Common ftr bits for a 32bit register with all hidden, strict
532  * attributes, with 4bit feature fields and a default safe value of
533  * 0. Covers the following 32bit registers:
534  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
535  */
536 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
537 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
538 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
539 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
541 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
542 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
543 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
544 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
545 	ARM64_FTR_END,
546 };
547 
548 /* Table for a single 32bit feature value */
549 static const struct arm64_ftr_bits ftr_single32[] = {
550 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
551 	ARM64_FTR_END,
552 };
553 
554 static const struct arm64_ftr_bits ftr_raz[] = {
555 	ARM64_FTR_END,
556 };
557 
558 #define ARM64_FTR_REG(id, table) {		\
559 	.sys_id = id,				\
560 	.reg = 	&(struct arm64_ftr_reg){	\
561 		.name = #id,			\
562 		.ftr_bits = &((table)[0]),	\
563 	}}
564 
565 static const struct __ftr_reg_entry {
566 	u32			sys_id;
567 	struct arm64_ftr_reg 	*reg;
568 } arm64_ftr_regs[] = {
569 
570 	/* Op1 = 0, CRn = 0, CRm = 1 */
571 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
572 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
573 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
574 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
575 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
576 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
577 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
578 
579 	/* Op1 = 0, CRn = 0, CRm = 2 */
580 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
581 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
582 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
583 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
584 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
585 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
586 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
587 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
588 
589 	/* Op1 = 0, CRn = 0, CRm = 3 */
590 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
591 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
592 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
593 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
594 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
595 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
596 
597 	/* Op1 = 0, CRn = 0, CRm = 4 */
598 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
599 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
600 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
601 
602 	/* Op1 = 0, CRn = 0, CRm = 5 */
603 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
604 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
605 
606 	/* Op1 = 0, CRn = 0, CRm = 6 */
607 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
608 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
609 	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
610 
611 	/* Op1 = 0, CRn = 0, CRm = 7 */
612 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
613 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
614 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
615 
616 	/* Op1 = 0, CRn = 1, CRm = 2 */
617 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
618 
619 	/* Op1 = 3, CRn = 0, CRm = 0 */
620 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
621 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
622 
623 	/* Op1 = 3, CRn = 14, CRm = 0 */
624 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
625 };
626 
search_cmp_ftr_reg(const void * id,const void * regp)627 static int search_cmp_ftr_reg(const void *id, const void *regp)
628 {
629 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
630 }
631 
632 /*
633  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
634  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
635  * ascending order of sys_id, we use binary search to find a matching
636  * entry.
637  *
638  * returns - Upon success,  matching ftr_reg entry for id.
639  *         - NULL on failure. It is upto the caller to decide
640  *	     the impact of a failure.
641  */
get_arm64_ftr_reg_nowarn(u32 sys_id)642 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
643 {
644 	const struct __ftr_reg_entry *ret;
645 
646 	ret = bsearch((const void *)(unsigned long)sys_id,
647 			arm64_ftr_regs,
648 			ARRAY_SIZE(arm64_ftr_regs),
649 			sizeof(arm64_ftr_regs[0]),
650 			search_cmp_ftr_reg);
651 	if (ret)
652 		return ret->reg;
653 	return NULL;
654 }
655 
656 /*
657  * get_arm64_ftr_reg - Looks up a feature register entry using
658  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
659  *
660  * returns - Upon success,  matching ftr_reg entry for id.
661  *         - NULL on failure but with an WARN_ON().
662  */
get_arm64_ftr_reg(u32 sys_id)663 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
664 {
665 	struct arm64_ftr_reg *reg;
666 
667 	reg = get_arm64_ftr_reg_nowarn(sys_id);
668 
669 	/*
670 	 * Requesting a non-existent register search is an error. Warn
671 	 * and let the caller handle it.
672 	 */
673 	WARN_ON(!reg);
674 	return reg;
675 }
676 
arm64_ftr_set_value(const struct arm64_ftr_bits * ftrp,s64 reg,s64 ftr_val)677 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
678 			       s64 ftr_val)
679 {
680 	u64 mask = arm64_ftr_mask(ftrp);
681 
682 	reg &= ~mask;
683 	reg |= (ftr_val << ftrp->shift) & mask;
684 	return reg;
685 }
686 
arm64_ftr_safe_value(const struct arm64_ftr_bits * ftrp,s64 new,s64 cur)687 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
688 				s64 cur)
689 {
690 	s64 ret = 0;
691 
692 	switch (ftrp->type) {
693 	case FTR_EXACT:
694 		ret = ftrp->safe_val;
695 		break;
696 	case FTR_LOWER_SAFE:
697 		ret = new < cur ? new : cur;
698 		break;
699 	case FTR_HIGHER_OR_ZERO_SAFE:
700 		if (!cur || !new)
701 			break;
702 		fallthrough;
703 	case FTR_HIGHER_SAFE:
704 		ret = new > cur ? new : cur;
705 		break;
706 	default:
707 		BUG();
708 	}
709 
710 	return ret;
711 }
712 
sort_ftr_regs(void)713 static void __init sort_ftr_regs(void)
714 {
715 	unsigned int i;
716 
717 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
718 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
719 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
720 		unsigned int j = 0;
721 
722 		/*
723 		 * Features here must be sorted in descending order with respect
724 		 * to their shift values and should not overlap with each other.
725 		 */
726 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
727 			unsigned int width = ftr_reg->ftr_bits[j].width;
728 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
729 			unsigned int prev_shift;
730 
731 			WARN((shift  + width) > 64,
732 				"%s has invalid feature at shift %d\n",
733 				ftr_reg->name, shift);
734 
735 			/*
736 			 * Skip the first feature. There is nothing to
737 			 * compare against for now.
738 			 */
739 			if (j == 0)
740 				continue;
741 
742 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
743 			WARN((shift + width) > prev_shift,
744 				"%s has feature overlap at shift %d\n",
745 				ftr_reg->name, shift);
746 		}
747 
748 		/*
749 		 * Skip the first register. There is nothing to
750 		 * compare against for now.
751 		 */
752 		if (i == 0)
753 			continue;
754 		/*
755 		 * Registers here must be sorted in ascending order with respect
756 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
757 		 * to work correctly.
758 		 */
759 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
760 	}
761 }
762 
763 /*
764  * Initialise the CPU feature register from Boot CPU values.
765  * Also initiliases the strict_mask for the register.
766  * Any bits that are not covered by an arm64_ftr_bits entry are considered
767  * RES0 for the system-wide value, and must strictly match.
768  */
init_cpu_ftr_reg(u32 sys_reg,u64 new)769 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
770 {
771 	u64 val = 0;
772 	u64 strict_mask = ~0x0ULL;
773 	u64 user_mask = 0;
774 	u64 valid_mask = 0;
775 
776 	const struct arm64_ftr_bits *ftrp;
777 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
778 
779 	if (!reg)
780 		return;
781 
782 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
783 		u64 ftr_mask = arm64_ftr_mask(ftrp);
784 		s64 ftr_new = arm64_ftr_value(ftrp, new);
785 
786 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
787 
788 		valid_mask |= ftr_mask;
789 		if (!ftrp->strict)
790 			strict_mask &= ~ftr_mask;
791 		if (ftrp->visible)
792 			user_mask |= ftr_mask;
793 		else
794 			reg->user_val = arm64_ftr_set_value(ftrp,
795 							    reg->user_val,
796 							    ftrp->safe_val);
797 	}
798 
799 	val &= valid_mask;
800 
801 	reg->sys_val = val;
802 	reg->strict_mask = strict_mask;
803 	reg->user_mask = user_mask;
804 }
805 
806 extern const struct arm64_cpu_capabilities arm64_errata[];
807 static const struct arm64_cpu_capabilities arm64_features[];
808 
809 static void __init
init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities * caps)810 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
811 {
812 	for (; caps->matches; caps++) {
813 		if (WARN(caps->capability >= ARM64_NCAPS,
814 			"Invalid capability %d\n", caps->capability))
815 			continue;
816 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
817 			"Duplicate entry for capability %d\n",
818 			caps->capability))
819 			continue;
820 		cpu_hwcaps_ptrs[caps->capability] = caps;
821 	}
822 }
823 
init_cpu_hwcaps_indirect_list(void)824 static void __init init_cpu_hwcaps_indirect_list(void)
825 {
826 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
827 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
828 }
829 
830 static void __init setup_boot_cpu_capabilities(void);
831 
init_cpu_features(struct cpuinfo_arm64 * info)832 void __init init_cpu_features(struct cpuinfo_arm64 *info)
833 {
834 	/* Before we start using the tables, make sure it is sorted */
835 	sort_ftr_regs();
836 
837 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
838 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
839 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
840 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
841 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
842 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
843 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
844 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
845 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
846 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
847 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
848 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
849 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
850 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
851 
852 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
853 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
854 		init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
855 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
856 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
857 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
858 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
859 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
860 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
861 		init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
862 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
863 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
864 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
865 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
866 		init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
867 		init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
868 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
869 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
870 		init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
871 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
872 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
873 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
874 	}
875 
876 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
877 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
878 		sve_init_vq_map();
879 	}
880 
881 	/*
882 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
883 	 * before we handle the boot CPU below.
884 	 */
885 	init_cpu_hwcaps_indirect_list();
886 
887 	/*
888 	 * Detect and enable early CPU capabilities based on the boot CPU,
889 	 * after we have initialised the CPU feature infrastructure.
890 	 */
891 	setup_boot_cpu_capabilities();
892 }
893 
update_cpu_ftr_reg(struct arm64_ftr_reg * reg,u64 new)894 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
895 {
896 	const struct arm64_ftr_bits *ftrp;
897 
898 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
899 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
900 		s64 ftr_new = arm64_ftr_value(ftrp, new);
901 
902 		if (ftr_cur == ftr_new)
903 			continue;
904 		/* Find a safe value */
905 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
906 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
907 	}
908 
909 }
910 
check_update_ftr_reg(u32 sys_id,int cpu,u64 val,u64 boot)911 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
912 {
913 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
914 
915 	if (!regp)
916 		return 0;
917 
918 	update_cpu_ftr_reg(regp, val);
919 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
920 		return 0;
921 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
922 			regp->name, boot, cpu, val);
923 	return 1;
924 }
925 
relax_cpu_ftr_reg(u32 sys_id,int field)926 static void relax_cpu_ftr_reg(u32 sys_id, int field)
927 {
928 	const struct arm64_ftr_bits *ftrp;
929 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
930 
931 	if (!regp)
932 		return;
933 
934 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
935 		if (ftrp->shift == field) {
936 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
937 			break;
938 		}
939 	}
940 
941 	/* Bogus field? */
942 	WARN_ON(!ftrp->width);
943 }
944 
update_32bit_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)945 static int update_32bit_cpu_features(int cpu, struct cpuinfo_arm64 *info,
946 				     struct cpuinfo_arm64 *boot)
947 {
948 	int taint = 0;
949 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
950 
951 	/*
952 	 * If we don't have AArch32 at all then skip the checks entirely
953 	 * as the register values may be UNKNOWN and we're not going to be
954 	 * using them for anything.
955 	 */
956 	if (!id_aa64pfr0_32bit_el0(pfr0))
957 		return taint;
958 
959 	/*
960 	 * If we don't have AArch32 at EL1, then relax the strictness of
961 	 * EL1-dependent register fields to avoid spurious sanity check fails.
962 	 */
963 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
964 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
965 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
966 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
967 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
968 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
969 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
970 	}
971 
972 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
973 				      info->reg_id_dfr0, boot->reg_id_dfr0);
974 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
975 				      info->reg_id_dfr1, boot->reg_id_dfr1);
976 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
977 				      info->reg_id_isar0, boot->reg_id_isar0);
978 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
979 				      info->reg_id_isar1, boot->reg_id_isar1);
980 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
981 				      info->reg_id_isar2, boot->reg_id_isar2);
982 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
983 				      info->reg_id_isar3, boot->reg_id_isar3);
984 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
985 				      info->reg_id_isar4, boot->reg_id_isar4);
986 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
987 				      info->reg_id_isar5, boot->reg_id_isar5);
988 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
989 				      info->reg_id_isar6, boot->reg_id_isar6);
990 
991 	/*
992 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
993 	 * ACTLR formats could differ across CPUs and therefore would have to
994 	 * be trapped for virtualization anyway.
995 	 */
996 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
997 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
998 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
999 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1000 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1001 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1002 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1003 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1004 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1005 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1006 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1007 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1008 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1009 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1010 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1011 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1012 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1013 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1014 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1015 				      info->reg_mvfr0, boot->reg_mvfr0);
1016 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1017 				      info->reg_mvfr1, boot->reg_mvfr1);
1018 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1019 				      info->reg_mvfr2, boot->reg_mvfr2);
1020 
1021 	return taint;
1022 }
1023 
1024 /*
1025  * Update system wide CPU feature registers with the values from a
1026  * non-boot CPU. Also performs SANITY checks to make sure that there
1027  * aren't any insane variations from that of the boot CPU.
1028  */
update_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)1029 void update_cpu_features(int cpu,
1030 			 struct cpuinfo_arm64 *info,
1031 			 struct cpuinfo_arm64 *boot)
1032 {
1033 	int taint = 0;
1034 
1035 	/*
1036 	 * The kernel can handle differing I-cache policies, but otherwise
1037 	 * caches should look identical. Userspace JITs will make use of
1038 	 * *minLine.
1039 	 */
1040 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1041 				      info->reg_ctr, boot->reg_ctr);
1042 
1043 	/*
1044 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1045 	 * could result in too much or too little memory being zeroed if a
1046 	 * process is preempted and migrated between CPUs.
1047 	 */
1048 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1049 				      info->reg_dczid, boot->reg_dczid);
1050 
1051 	/* If different, timekeeping will be broken (especially with KVM) */
1052 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1053 				      info->reg_cntfrq, boot->reg_cntfrq);
1054 
1055 	/*
1056 	 * The kernel uses self-hosted debug features and expects CPUs to
1057 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1058 	 * and BRPs to be identical.
1059 	 * ID_AA64DFR1 is currently RES0.
1060 	 */
1061 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1062 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1063 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1064 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1065 	/*
1066 	 * Even in big.LITTLE, processors should be identical instruction-set
1067 	 * wise.
1068 	 */
1069 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1070 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1071 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1072 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1073 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1074 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1075 
1076 	/*
1077 	 * Differing PARange support is fine as long as all peripherals and
1078 	 * memory are mapped within the minimum PARange of all CPUs.
1079 	 * Linux should not care about secure memory.
1080 	 */
1081 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1082 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1083 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1084 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1085 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1086 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1087 
1088 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1089 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1090 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1091 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1092 
1093 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1094 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1095 
1096 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1097 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1098 					info->reg_zcr, boot->reg_zcr);
1099 
1100 		/* Probe vector lengths, unless we already gave up on SVE */
1101 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1102 		    !system_capabilities_finalized())
1103 			sve_update_vq_map();
1104 	}
1105 
1106 	/*
1107 	 * This relies on a sanitised view of the AArch64 ID registers
1108 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1109 	 */
1110 	taint |= update_32bit_cpu_features(cpu, info, boot);
1111 
1112 	/*
1113 	 * Mismatched CPU features are a recipe for disaster. Don't even
1114 	 * pretend to support them.
1115 	 */
1116 	if (taint) {
1117 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1118 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1119 	}
1120 }
1121 
read_sanitised_ftr_reg(u32 id)1122 u64 read_sanitised_ftr_reg(u32 id)
1123 {
1124 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1125 
1126 	if (!regp)
1127 		return 0;
1128 	return regp->sys_val;
1129 }
1130 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1131 
1132 #define read_sysreg_case(r)	\
1133 	case r:		return read_sysreg_s(r)
1134 
1135 /*
1136  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1137  * Read the system register on the current CPU
1138  */
__read_sysreg_by_encoding(u32 sys_id)1139 static u64 __read_sysreg_by_encoding(u32 sys_id)
1140 {
1141 	switch (sys_id) {
1142 	read_sysreg_case(SYS_ID_PFR0_EL1);
1143 	read_sysreg_case(SYS_ID_PFR1_EL1);
1144 	read_sysreg_case(SYS_ID_PFR2_EL1);
1145 	read_sysreg_case(SYS_ID_DFR0_EL1);
1146 	read_sysreg_case(SYS_ID_DFR1_EL1);
1147 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1148 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1149 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1150 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1151 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1152 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1153 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1154 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1155 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1156 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1157 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1158 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1159 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1160 	read_sysreg_case(SYS_MVFR0_EL1);
1161 	read_sysreg_case(SYS_MVFR1_EL1);
1162 	read_sysreg_case(SYS_MVFR2_EL1);
1163 
1164 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1165 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1166 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1167 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1168 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1169 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1170 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1171 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1172 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1173 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1174 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1175 
1176 	read_sysreg_case(SYS_CNTFRQ_EL0);
1177 	read_sysreg_case(SYS_CTR_EL0);
1178 	read_sysreg_case(SYS_DCZID_EL0);
1179 
1180 	default:
1181 		BUG();
1182 		return 0;
1183 	}
1184 }
1185 
1186 #include <linux/irqchip/arm-gic-v3.h>
1187 
1188 static bool
feature_matches(u64 reg,const struct arm64_cpu_capabilities * entry)1189 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1190 {
1191 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1192 
1193 	return val >= entry->min_field_value;
1194 }
1195 
1196 static bool
has_cpuid_feature(const struct arm64_cpu_capabilities * entry,int scope)1197 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1198 {
1199 	u64 val;
1200 
1201 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1202 	if (scope == SCOPE_SYSTEM)
1203 		val = read_sanitised_ftr_reg(entry->sys_reg);
1204 	else
1205 		val = __read_sysreg_by_encoding(entry->sys_reg);
1206 
1207 	return feature_matches(val, entry);
1208 }
1209 
has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities * entry,int scope)1210 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1211 {
1212 	bool has_sre;
1213 
1214 	if (!has_cpuid_feature(entry, scope))
1215 		return false;
1216 
1217 	has_sre = gic_enable_sre();
1218 	if (!has_sre)
1219 		pr_warn_once("%s present but disabled by higher exception level\n",
1220 			     entry->desc);
1221 
1222 	return has_sre;
1223 }
1224 
has_no_hw_prefetch(const struct arm64_cpu_capabilities * entry,int __unused)1225 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1226 {
1227 	u32 midr = read_cpuid_id();
1228 
1229 	/* Cavium ThunderX pass 1.x and 2.x */
1230 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1231 		MIDR_CPU_VAR_REV(0, 0),
1232 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1233 }
1234 
has_no_fpsimd(const struct arm64_cpu_capabilities * entry,int __unused)1235 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1236 {
1237 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1238 
1239 	return cpuid_feature_extract_signed_field(pfr0,
1240 					ID_AA64PFR0_FP_SHIFT) < 0;
1241 }
1242 
has_cache_idc(const struct arm64_cpu_capabilities * entry,int scope)1243 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1244 			  int scope)
1245 {
1246 	u64 ctr;
1247 
1248 	if (scope == SCOPE_SYSTEM)
1249 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1250 	else
1251 		ctr = read_cpuid_effective_cachetype();
1252 
1253 	return ctr & BIT(CTR_IDC_SHIFT);
1254 }
1255 
cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities * __unused)1256 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1257 {
1258 	/*
1259 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1260 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1261 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1262 	 * value.
1263 	 */
1264 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1265 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1266 }
1267 
has_cache_dic(const struct arm64_cpu_capabilities * entry,int scope)1268 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1269 			  int scope)
1270 {
1271 	u64 ctr;
1272 
1273 	if (scope == SCOPE_SYSTEM)
1274 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1275 	else
1276 		ctr = read_cpuid_cachetype();
1277 
1278 	return ctr & BIT(CTR_DIC_SHIFT);
1279 }
1280 
1281 static bool __maybe_unused
has_useable_cnp(const struct arm64_cpu_capabilities * entry,int scope)1282 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1283 {
1284 	/*
1285 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1286 	 * may share TLB entries with a CPU stuck in the crashed
1287 	 * kernel.
1288 	 */
1289 	 if (is_kdump_kernel())
1290 		return false;
1291 
1292 	return has_cpuid_feature(entry, scope);
1293 }
1294 
1295 /*
1296  * This check is triggered during the early boot before the cpufeature
1297  * is initialised. Checking the status on the local CPU allows the boot
1298  * CPU to detect the need for non-global mappings and thus avoiding a
1299  * pagetable re-write after all the CPUs are booted. This check will be
1300  * anyway run on individual CPUs, allowing us to get the consistent
1301  * state once the SMP CPUs are up and thus make the switch to non-global
1302  * mappings if required.
1303  */
kaslr_requires_kpti(void)1304 bool kaslr_requires_kpti(void)
1305 {
1306 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1307 		return false;
1308 
1309 	/*
1310 	 * E0PD does a similar job to KPTI so can be used instead
1311 	 * where available.
1312 	 */
1313 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1314 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1315 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1316 						ID_AA64MMFR2_E0PD_SHIFT))
1317 			return false;
1318 	}
1319 
1320 	/*
1321 	 * Systems affected by Cavium erratum 24756 are incompatible
1322 	 * with KPTI.
1323 	 */
1324 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1325 		extern const struct midr_range cavium_erratum_27456_cpus[];
1326 
1327 		if (is_midr_in_range_list(read_cpuid_id(),
1328 					  cavium_erratum_27456_cpus))
1329 			return false;
1330 	}
1331 
1332 	return kaslr_offset() > 0;
1333 }
1334 
1335 static bool __meltdown_safe = true;
1336 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1337 
unmap_kernel_at_el0(const struct arm64_cpu_capabilities * entry,int scope)1338 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1339 				int scope)
1340 {
1341 	/* List of CPUs that are not vulnerable and don't need KPTI */
1342 	static const struct midr_range kpti_safe_list[] = {
1343 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1344 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1345 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1346 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1347 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1348 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1349 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1350 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1351 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1352 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1353 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1354 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1355 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1356 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1357 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1358 		{ /* sentinel */ }
1359 	};
1360 	char const *str = "kpti command line option";
1361 	bool meltdown_safe;
1362 
1363 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1364 
1365 	/* Defer to CPU feature registers */
1366 	if (has_cpuid_feature(entry, scope))
1367 		meltdown_safe = true;
1368 
1369 	if (!meltdown_safe)
1370 		__meltdown_safe = false;
1371 
1372 	/*
1373 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1374 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1375 	 * ends as well as you might imagine. Don't even try.
1376 	 */
1377 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1378 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1379 		__kpti_forced = -1;
1380 	}
1381 
1382 	/* Useful for KASLR robustness */
1383 	if (kaslr_requires_kpti()) {
1384 		if (!__kpti_forced) {
1385 			str = "KASLR";
1386 			__kpti_forced = 1;
1387 		}
1388 	}
1389 
1390 	if (cpu_mitigations_off() && !__kpti_forced) {
1391 		str = "mitigations=off";
1392 		__kpti_forced = -1;
1393 	}
1394 
1395 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1396 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1397 		return false;
1398 	}
1399 
1400 	/* Forced? */
1401 	if (__kpti_forced) {
1402 		pr_info_once("kernel page table isolation forced %s by %s\n",
1403 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1404 		return __kpti_forced > 0;
1405 	}
1406 
1407 	return !meltdown_safe;
1408 }
1409 
1410 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1411 static void __nocfi
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1412 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1413 {
1414 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1415 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1416 	kpti_remap_fn *remap_fn;
1417 
1418 	int cpu = smp_processor_id();
1419 
1420 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1421 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1422 
1423 		__this_cpu_write(this_cpu_vector, v);
1424 	}
1425 
1426 	/*
1427 	 * We don't need to rewrite the page-tables if either we've done
1428 	 * it already or we have KASLR enabled and therefore have not
1429 	 * created any global mappings at all.
1430 	 */
1431 	if (arm64_use_ng_mappings)
1432 		return;
1433 
1434 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1435 
1436 	cpu_install_idmap();
1437 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1438 	cpu_uninstall_idmap();
1439 
1440 	if (!cpu)
1441 		arm64_use_ng_mappings = true;
1442 
1443 	return;
1444 }
1445 #else
1446 static void
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1447 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1448 {
1449 }
1450 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1451 
parse_kpti(char * str)1452 static int __init parse_kpti(char *str)
1453 {
1454 	bool enabled;
1455 	int ret = strtobool(str, &enabled);
1456 
1457 	if (ret)
1458 		return ret;
1459 
1460 	__kpti_forced = enabled ? 1 : -1;
1461 	return 0;
1462 }
1463 early_param("kpti", parse_kpti);
1464 
1465 #ifdef CONFIG_ARM64_HW_AFDBM
__cpu_enable_hw_dbm(void)1466 static inline void __cpu_enable_hw_dbm(void)
1467 {
1468 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1469 
1470 	write_sysreg(tcr, tcr_el1);
1471 	isb();
1472 	local_flush_tlb_all();
1473 }
1474 
cpu_has_broken_dbm(void)1475 static bool cpu_has_broken_dbm(void)
1476 {
1477 	/* List of CPUs which have broken DBM support. */
1478 	static const struct midr_range cpus[] = {
1479 #ifdef CONFIG_ARM64_ERRATUM_1024718
1480 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1481 		/* Kryo4xx Silver (rdpe => r1p0) */
1482 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1483 #endif
1484 		{},
1485 	};
1486 
1487 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1488 }
1489 
cpu_can_use_dbm(const struct arm64_cpu_capabilities * cap)1490 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1491 {
1492 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1493 	       !cpu_has_broken_dbm();
1494 }
1495 
cpu_enable_hw_dbm(struct arm64_cpu_capabilities const * cap)1496 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1497 {
1498 	if (cpu_can_use_dbm(cap))
1499 		__cpu_enable_hw_dbm();
1500 }
1501 
has_hw_dbm(const struct arm64_cpu_capabilities * cap,int __unused)1502 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1503 		       int __unused)
1504 {
1505 	static bool detected = false;
1506 	/*
1507 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1508 	 * run a mix of CPUs with and without the feature. So, we
1509 	 * unconditionally enable the capability to allow any late CPU
1510 	 * to use the feature. We only enable the control bits on the
1511 	 * CPU, if it actually supports.
1512 	 *
1513 	 * We have to make sure we print the "feature" detection only
1514 	 * when at least one CPU actually uses it. So check if this CPU
1515 	 * can actually use it and print the message exactly once.
1516 	 *
1517 	 * This is safe as all CPUs (including secondary CPUs - due to the
1518 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1519 	 * goes through the "matches" check exactly once. Also if a CPU
1520 	 * matches the criteria, it is guaranteed that the CPU will turn
1521 	 * the DBM on, as the capability is unconditionally enabled.
1522 	 */
1523 	if (!detected && cpu_can_use_dbm(cap)) {
1524 		detected = true;
1525 		pr_info("detected: Hardware dirty bit management\n");
1526 	}
1527 
1528 	return true;
1529 }
1530 
1531 #endif
1532 
1533 #ifdef CONFIG_ARM64_AMU_EXTN
1534 
1535 /*
1536  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1537  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1538  * information regarding all the events that it supports. When a CPU bit is
1539  * set in the cpumask, the user of this feature can only rely on the presence
1540  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1541  * counters are enabled or access to these counters is enabled by code
1542  * executed at higher exception levels (firmware).
1543  */
1544 static struct cpumask amu_cpus __read_mostly;
1545 
cpu_has_amu_feat(int cpu)1546 bool cpu_has_amu_feat(int cpu)
1547 {
1548 	return cpumask_test_cpu(cpu, &amu_cpus);
1549 }
1550 
1551 /* Initialize the use of AMU counters for frequency invariance */
1552 extern void init_cpu_freq_invariance_counters(void);
1553 
cpu_amu_enable(struct arm64_cpu_capabilities const * cap)1554 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1555 {
1556 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1557 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1558 			smp_processor_id());
1559 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1560 		init_cpu_freq_invariance_counters();
1561 	}
1562 }
1563 
has_amu(const struct arm64_cpu_capabilities * cap,int __unused)1564 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1565 		    int __unused)
1566 {
1567 	/*
1568 	 * The AMU extension is a non-conflicting feature: the kernel can
1569 	 * safely run a mix of CPUs with and without support for the
1570 	 * activity monitors extension. Therefore, unconditionally enable
1571 	 * the capability to allow any late CPU to use the feature.
1572 	 *
1573 	 * With this feature unconditionally enabled, the cpu_enable
1574 	 * function will be called for all CPUs that match the criteria,
1575 	 * including secondary and hotplugged, marking this feature as
1576 	 * present on that respective CPU. The enable function will also
1577 	 * print a detection message.
1578 	 */
1579 
1580 	return true;
1581 }
1582 #endif
1583 
1584 #ifdef CONFIG_ARM64_VHE
runs_at_el2(const struct arm64_cpu_capabilities * entry,int __unused)1585 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1586 {
1587 	return is_kernel_in_hyp_mode();
1588 }
1589 
cpu_copy_el2regs(const struct arm64_cpu_capabilities * __unused)1590 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1591 {
1592 	/*
1593 	 * Copy register values that aren't redirected by hardware.
1594 	 *
1595 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1596 	 * this value to tpidr_el2 before we patch the code. Once we've done
1597 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1598 	 * do anything here.
1599 	 */
1600 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1601 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1602 }
1603 #endif
1604 
cpu_has_fwb(const struct arm64_cpu_capabilities * __unused)1605 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1606 {
1607 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1608 
1609 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1610 	WARN_ON(val & (7 << 27 | 7 << 21));
1611 }
1612 
1613 #ifdef CONFIG_ARM64_PAN
cpu_enable_pan(const struct arm64_cpu_capabilities * __unused)1614 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1615 {
1616 	/*
1617 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1618 	 * is discarded once we return from the exception.
1619 	 */
1620 	WARN_ON_ONCE(in_interrupt());
1621 
1622 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1623 	asm(SET_PSTATE_PAN(1));
1624 }
1625 #endif /* CONFIG_ARM64_PAN */
1626 
1627 #ifdef CONFIG_ARM64_RAS_EXTN
cpu_clear_disr(const struct arm64_cpu_capabilities * __unused)1628 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1629 {
1630 	/* Firmware may have left a deferred SError in this register. */
1631 	write_sysreg_s(0, SYS_DISR_EL1);
1632 }
1633 #endif /* CONFIG_ARM64_RAS_EXTN */
1634 
1635 #ifdef CONFIG_ARM64_PTR_AUTH
has_address_auth_cpucap(const struct arm64_cpu_capabilities * entry,int scope)1636 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1637 {
1638 	int boot_val, sec_val;
1639 
1640 	/* We don't expect to be called with SCOPE_SYSTEM */
1641 	WARN_ON(scope == SCOPE_SYSTEM);
1642 	/*
1643 	 * The ptr-auth feature levels are not intercompatible with lower
1644 	 * levels. Hence we must match ptr-auth feature level of the secondary
1645 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1646 	 * from the sanitised register whereas direct register read is done for
1647 	 * the secondary CPUs.
1648 	 * The sanitised feature state is guaranteed to match that of the
1649 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1650 	 * a chance to update the state, with the capability.
1651 	 */
1652 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1653 					       entry->field_pos, entry->sign);
1654 	if (scope & SCOPE_BOOT_CPU)
1655 		return boot_val >= entry->min_field_value;
1656 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1657 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1658 					      entry->field_pos, entry->sign);
1659 	return sec_val == boot_val;
1660 }
1661 
has_address_auth_metacap(const struct arm64_cpu_capabilities * entry,int scope)1662 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1663 				     int scope)
1664 {
1665 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1666 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1667 }
1668 
has_generic_auth(const struct arm64_cpu_capabilities * entry,int __unused)1669 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1670 			     int __unused)
1671 {
1672 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1673 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1674 }
1675 #endif /* CONFIG_ARM64_PTR_AUTH */
1676 
1677 #ifdef CONFIG_ARM64_E0PD
cpu_enable_e0pd(struct arm64_cpu_capabilities const * cap)1678 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1679 {
1680 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1681 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1682 }
1683 #endif /* CONFIG_ARM64_E0PD */
1684 
1685 #ifdef CONFIG_ARM64_PSEUDO_NMI
1686 static bool enable_pseudo_nmi;
1687 
early_enable_pseudo_nmi(char * p)1688 static int __init early_enable_pseudo_nmi(char *p)
1689 {
1690 	return strtobool(p, &enable_pseudo_nmi);
1691 }
1692 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1693 
can_use_gic_priorities(const struct arm64_cpu_capabilities * entry,int scope)1694 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1695 				   int scope)
1696 {
1697 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1698 }
1699 #endif
1700 
1701 #ifdef CONFIG_ARM64_BTI
bti_enable(const struct arm64_cpu_capabilities * __unused)1702 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1703 {
1704 	/*
1705 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1706 	 * function entry points using BR is a requirement for
1707 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1708 	 * So, be strict and forbid other BRs using other registers to
1709 	 * jump onto a PACIxSP instruction:
1710 	 */
1711 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1712 	isb();
1713 }
1714 #endif /* CONFIG_ARM64_BTI */
1715 
1716 #ifdef CONFIG_ARM64_MTE
cpu_enable_mte(struct arm64_cpu_capabilities const * cap)1717 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1718 {
1719 	/*
1720 	 * Clear the tags in the zero page. This needs to be done via the
1721 	 * linear map which has the Tagged attribute.
1722 	 */
1723 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1724 		mte_clear_page_tags(lm_alias(empty_zero_page));
1725 }
1726 #endif /* CONFIG_ARM64_MTE */
1727 
1728 /* Internal helper functions to match cpu capability type */
1729 static bool
cpucap_late_cpu_optional(const struct arm64_cpu_capabilities * cap)1730 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1731 {
1732 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1733 }
1734 
1735 static bool
cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities * cap)1736 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1737 {
1738 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1739 }
1740 
1741 static bool
cpucap_panic_on_conflict(const struct arm64_cpu_capabilities * cap)1742 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1743 {
1744 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1745 }
1746 
1747 static const struct arm64_cpu_capabilities arm64_features[] = {
1748 	{
1749 		.desc = "GIC system register CPU interface",
1750 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1751 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1752 		.matches = has_useable_gicv3_cpuif,
1753 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1754 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1755 		.sign = FTR_UNSIGNED,
1756 		.min_field_value = 1,
1757 	},
1758 #ifdef CONFIG_ARM64_PAN
1759 	{
1760 		.desc = "Privileged Access Never",
1761 		.capability = ARM64_HAS_PAN,
1762 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1763 		.matches = has_cpuid_feature,
1764 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1765 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1766 		.sign = FTR_UNSIGNED,
1767 		.min_field_value = 1,
1768 		.cpu_enable = cpu_enable_pan,
1769 	},
1770 #endif /* CONFIG_ARM64_PAN */
1771 #ifdef CONFIG_ARM64_LSE_ATOMICS
1772 	{
1773 		.desc = "LSE atomic instructions",
1774 		.capability = ARM64_HAS_LSE_ATOMICS,
1775 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1776 		.matches = has_cpuid_feature,
1777 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1778 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1779 		.sign = FTR_UNSIGNED,
1780 		.min_field_value = 2,
1781 	},
1782 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1783 	{
1784 		.desc = "Software prefetching using PRFM",
1785 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1786 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1787 		.matches = has_no_hw_prefetch,
1788 	},
1789 #ifdef CONFIG_ARM64_UAO
1790 	{
1791 		.desc = "User Access Override",
1792 		.capability = ARM64_HAS_UAO,
1793 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1794 		.matches = has_cpuid_feature,
1795 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1796 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
1797 		.min_field_value = 1,
1798 		/*
1799 		 * We rely on stop_machine() calling uao_thread_switch() to set
1800 		 * UAO immediately after patching.
1801 		 */
1802 	},
1803 #endif /* CONFIG_ARM64_UAO */
1804 #ifdef CONFIG_ARM64_PAN
1805 	{
1806 		.capability = ARM64_ALT_PAN_NOT_UAO,
1807 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1808 		.matches = cpufeature_pan_not_uao,
1809 	},
1810 #endif /* CONFIG_ARM64_PAN */
1811 #ifdef CONFIG_ARM64_VHE
1812 	{
1813 		.desc = "Virtualization Host Extensions",
1814 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1815 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1816 		.matches = runs_at_el2,
1817 		.cpu_enable = cpu_copy_el2regs,
1818 	},
1819 #endif	/* CONFIG_ARM64_VHE */
1820 	{
1821 		.desc = "32-bit EL0 Support",
1822 		.capability = ARM64_HAS_32BIT_EL0,
1823 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1824 		.matches = has_cpuid_feature,
1825 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1826 		.sign = FTR_UNSIGNED,
1827 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1828 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1829 	},
1830 #ifdef CONFIG_KVM
1831 	{
1832 		.desc = "32-bit EL1 Support",
1833 		.capability = ARM64_HAS_32BIT_EL1,
1834 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1835 		.matches = has_cpuid_feature,
1836 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1837 		.sign = FTR_UNSIGNED,
1838 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
1839 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
1840 	},
1841 #endif
1842 	{
1843 		.desc = "Kernel page table isolation (KPTI)",
1844 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1845 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1846 		/*
1847 		 * The ID feature fields below are used to indicate that
1848 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1849 		 * more details.
1850 		 */
1851 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1852 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1853 		.min_field_value = 1,
1854 		.matches = unmap_kernel_at_el0,
1855 		.cpu_enable = kpti_install_ng_mappings,
1856 	},
1857 	{
1858 		/* FP/SIMD is not implemented */
1859 		.capability = ARM64_HAS_NO_FPSIMD,
1860 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1861 		.min_field_value = 0,
1862 		.matches = has_no_fpsimd,
1863 	},
1864 #ifdef CONFIG_ARM64_PMEM
1865 	{
1866 		.desc = "Data cache clean to Point of Persistence",
1867 		.capability = ARM64_HAS_DCPOP,
1868 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1869 		.matches = has_cpuid_feature,
1870 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1871 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1872 		.min_field_value = 1,
1873 	},
1874 	{
1875 		.desc = "Data cache clean to Point of Deep Persistence",
1876 		.capability = ARM64_HAS_DCPODP,
1877 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1878 		.matches = has_cpuid_feature,
1879 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1880 		.sign = FTR_UNSIGNED,
1881 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1882 		.min_field_value = 2,
1883 	},
1884 #endif
1885 #ifdef CONFIG_ARM64_SVE
1886 	{
1887 		.desc = "Scalable Vector Extension",
1888 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1889 		.capability = ARM64_SVE,
1890 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1891 		.sign = FTR_UNSIGNED,
1892 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
1893 		.min_field_value = ID_AA64PFR0_SVE,
1894 		.matches = has_cpuid_feature,
1895 		.cpu_enable = sve_kernel_enable,
1896 	},
1897 #endif /* CONFIG_ARM64_SVE */
1898 #ifdef CONFIG_ARM64_RAS_EXTN
1899 	{
1900 		.desc = "RAS Extension Support",
1901 		.capability = ARM64_HAS_RAS_EXTN,
1902 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1903 		.matches = has_cpuid_feature,
1904 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1905 		.sign = FTR_UNSIGNED,
1906 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
1907 		.min_field_value = ID_AA64PFR0_RAS_V1,
1908 		.cpu_enable = cpu_clear_disr,
1909 	},
1910 #endif /* CONFIG_ARM64_RAS_EXTN */
1911 #ifdef CONFIG_ARM64_AMU_EXTN
1912 	{
1913 		/*
1914 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
1915 		 * Therefore, don't provide .desc as we don't want the detection
1916 		 * message to be shown until at least one CPU is detected to
1917 		 * support the feature.
1918 		 */
1919 		.capability = ARM64_HAS_AMU_EXTN,
1920 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1921 		.matches = has_amu,
1922 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1923 		.sign = FTR_UNSIGNED,
1924 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
1925 		.min_field_value = ID_AA64PFR0_AMU,
1926 		.cpu_enable = cpu_amu_enable,
1927 	},
1928 #endif /* CONFIG_ARM64_AMU_EXTN */
1929 	{
1930 		.desc = "Data cache clean to the PoU not required for I/D coherence",
1931 		.capability = ARM64_HAS_CACHE_IDC,
1932 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1933 		.matches = has_cache_idc,
1934 		.cpu_enable = cpu_emulate_effective_ctr,
1935 	},
1936 	{
1937 		.desc = "Instruction cache invalidation not required for I/D coherence",
1938 		.capability = ARM64_HAS_CACHE_DIC,
1939 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1940 		.matches = has_cache_dic,
1941 	},
1942 	{
1943 		.desc = "Stage-2 Force Write-Back",
1944 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1945 		.capability = ARM64_HAS_STAGE2_FWB,
1946 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1947 		.sign = FTR_UNSIGNED,
1948 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
1949 		.min_field_value = 1,
1950 		.matches = has_cpuid_feature,
1951 		.cpu_enable = cpu_has_fwb,
1952 	},
1953 	{
1954 		.desc = "ARMv8.4 Translation Table Level",
1955 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1956 		.capability = ARM64_HAS_ARMv8_4_TTL,
1957 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1958 		.sign = FTR_UNSIGNED,
1959 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
1960 		.min_field_value = 1,
1961 		.matches = has_cpuid_feature,
1962 	},
1963 	{
1964 		.desc = "TLB range maintenance instructions",
1965 		.capability = ARM64_HAS_TLB_RANGE,
1966 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1967 		.matches = has_cpuid_feature,
1968 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1969 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
1970 		.sign = FTR_UNSIGNED,
1971 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
1972 	},
1973 #ifdef CONFIG_ARM64_HW_AFDBM
1974 	{
1975 		/*
1976 		 * Since we turn this on always, we don't want the user to
1977 		 * think that the feature is available when it may not be.
1978 		 * So hide the description.
1979 		 *
1980 		 * .desc = "Hardware pagetable Dirty Bit Management",
1981 		 *
1982 		 */
1983 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1984 		.capability = ARM64_HW_DBM,
1985 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1986 		.sign = FTR_UNSIGNED,
1987 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
1988 		.min_field_value = 2,
1989 		.matches = has_hw_dbm,
1990 		.cpu_enable = cpu_enable_hw_dbm,
1991 	},
1992 #endif
1993 	{
1994 		.desc = "CRC32 instructions",
1995 		.capability = ARM64_HAS_CRC32,
1996 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1997 		.matches = has_cpuid_feature,
1998 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1999 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2000 		.min_field_value = 1,
2001 	},
2002 	{
2003 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2004 		.capability = ARM64_SSBS,
2005 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2006 		.matches = has_cpuid_feature,
2007 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2008 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2009 		.sign = FTR_UNSIGNED,
2010 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2011 	},
2012 #ifdef CONFIG_ARM64_CNP
2013 	{
2014 		.desc = "Common not Private translations",
2015 		.capability = ARM64_HAS_CNP,
2016 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2017 		.matches = has_useable_cnp,
2018 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2019 		.sign = FTR_UNSIGNED,
2020 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2021 		.min_field_value = 1,
2022 		.cpu_enable = cpu_enable_cnp,
2023 	},
2024 #endif
2025 	{
2026 		.desc = "Speculation barrier (SB)",
2027 		.capability = ARM64_HAS_SB,
2028 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2029 		.matches = has_cpuid_feature,
2030 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2031 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2032 		.sign = FTR_UNSIGNED,
2033 		.min_field_value = 1,
2034 	},
2035 #ifdef CONFIG_ARM64_PTR_AUTH
2036 	{
2037 		.desc = "Address authentication (architected algorithm)",
2038 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2039 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2040 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2041 		.sign = FTR_UNSIGNED,
2042 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2043 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2044 		.matches = has_address_auth_cpucap,
2045 	},
2046 	{
2047 		.desc = "Address authentication (IMP DEF algorithm)",
2048 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2049 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2050 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2051 		.sign = FTR_UNSIGNED,
2052 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2053 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2054 		.matches = has_address_auth_cpucap,
2055 	},
2056 	{
2057 		.capability = ARM64_HAS_ADDRESS_AUTH,
2058 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2059 		.matches = has_address_auth_metacap,
2060 	},
2061 	{
2062 		.desc = "Generic authentication (architected algorithm)",
2063 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2064 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2065 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2066 		.sign = FTR_UNSIGNED,
2067 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2068 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2069 		.matches = has_cpuid_feature,
2070 	},
2071 	{
2072 		.desc = "Generic authentication (IMP DEF algorithm)",
2073 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2074 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2075 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2076 		.sign = FTR_UNSIGNED,
2077 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2078 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2079 		.matches = has_cpuid_feature,
2080 	},
2081 	{
2082 		.capability = ARM64_HAS_GENERIC_AUTH,
2083 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2084 		.matches = has_generic_auth,
2085 	},
2086 #endif /* CONFIG_ARM64_PTR_AUTH */
2087 #ifdef CONFIG_ARM64_PSEUDO_NMI
2088 	{
2089 		/*
2090 		 * Depends on having GICv3
2091 		 */
2092 		.desc = "IRQ priority masking",
2093 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2094 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2095 		.matches = can_use_gic_priorities,
2096 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2097 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2098 		.sign = FTR_UNSIGNED,
2099 		.min_field_value = 1,
2100 	},
2101 #endif
2102 #ifdef CONFIG_ARM64_E0PD
2103 	{
2104 		.desc = "E0PD",
2105 		.capability = ARM64_HAS_E0PD,
2106 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2107 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2108 		.sign = FTR_UNSIGNED,
2109 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2110 		.matches = has_cpuid_feature,
2111 		.min_field_value = 1,
2112 		.cpu_enable = cpu_enable_e0pd,
2113 	},
2114 #endif
2115 #ifdef CONFIG_ARCH_RANDOM
2116 	{
2117 		.desc = "Random Number Generator",
2118 		.capability = ARM64_HAS_RNG,
2119 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2120 		.matches = has_cpuid_feature,
2121 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2122 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2123 		.sign = FTR_UNSIGNED,
2124 		.min_field_value = 1,
2125 	},
2126 #endif
2127 #ifdef CONFIG_ARM64_BTI
2128 	{
2129 		.desc = "Branch Target Identification",
2130 		.capability = ARM64_BTI,
2131 #ifdef CONFIG_ARM64_BTI_KERNEL
2132 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2133 #else
2134 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2135 #endif
2136 		.matches = has_cpuid_feature,
2137 		.cpu_enable = bti_enable,
2138 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2139 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2140 		.min_field_value = ID_AA64PFR1_BT_BTI,
2141 		.sign = FTR_UNSIGNED,
2142 	},
2143 #endif
2144 #ifdef CONFIG_ARM64_MTE
2145 	{
2146 		.desc = "Memory Tagging Extension",
2147 		.capability = ARM64_MTE,
2148 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2149 		.matches = has_cpuid_feature,
2150 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2151 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2152 		.min_field_value = ID_AA64PFR1_MTE,
2153 		.sign = FTR_UNSIGNED,
2154 		.cpu_enable = cpu_enable_mte,
2155 	},
2156 #endif /* CONFIG_ARM64_MTE */
2157 	{},
2158 };
2159 
2160 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2161 		.matches = has_cpuid_feature,					\
2162 		.sys_reg = reg,							\
2163 		.field_pos = field,						\
2164 		.sign = s,							\
2165 		.min_field_value = min_value,
2166 
2167 #define __HWCAP_CAP(name, cap_type, cap)					\
2168 		.desc = name,							\
2169 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2170 		.hwcap_type = cap_type,						\
2171 		.hwcap = cap,							\
2172 
2173 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2174 	{									\
2175 		__HWCAP_CAP(#cap, cap_type, cap)				\
2176 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2177 	}
2178 
2179 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2180 	{									\
2181 		__HWCAP_CAP(#cap, cap_type, cap)				\
2182 		.matches = cpucap_multi_entry_cap_matches,			\
2183 		.match_list = list,						\
2184 	}
2185 
2186 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2187 	{									\
2188 		__HWCAP_CAP(#cap, cap_type, cap)				\
2189 		.matches = match,						\
2190 	}
2191 
2192 #ifdef CONFIG_ARM64_PTR_AUTH
2193 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2194 	{
2195 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2196 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2197 	},
2198 	{
2199 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2200 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2201 	},
2202 	{},
2203 };
2204 
2205 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2206 	{
2207 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2208 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2209 	},
2210 	{
2211 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2212 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2213 	},
2214 	{},
2215 };
2216 #endif
2217 
2218 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2219 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2220 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2221 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2222 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2223 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2224 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2225 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2226 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2227 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2228 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2229 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2230 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2231 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2232 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2233 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2234 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2235 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2236 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2237 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2238 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2239 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2240 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2241 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2242 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2243 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2244 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2245 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2246 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2247 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2248 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2249 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2250 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2251 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2252 #ifdef CONFIG_ARM64_SVE
2253 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2254 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2255 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2256 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2257 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2258 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2259 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2260 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2261 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2262 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2263 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2264 #endif
2265 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2266 #ifdef CONFIG_ARM64_BTI
2267 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2268 #endif
2269 #ifdef CONFIG_ARM64_PTR_AUTH
2270 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2271 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2272 #endif
2273 #ifdef CONFIG_ARM64_MTE
2274 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2275 #endif /* CONFIG_ARM64_MTE */
2276 	{},
2277 };
2278 
2279 #ifdef CONFIG_COMPAT
compat_has_neon(const struct arm64_cpu_capabilities * cap,int scope)2280 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2281 {
2282 	/*
2283 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2284 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2285 	 * check is future proof, by making sure value is non-zero.
2286 	 */
2287 	u32 mvfr1;
2288 
2289 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2290 	if (scope == SCOPE_SYSTEM)
2291 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2292 	else
2293 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2294 
2295 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2296 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2297 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2298 }
2299 #endif
2300 
2301 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2302 #ifdef CONFIG_COMPAT
2303 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2304 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2305 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2306 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2307 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2308 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2309 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2310 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2311 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2312 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2313 #endif
2314 	{},
2315 };
2316 
cap_set_elf_hwcap(const struct arm64_cpu_capabilities * cap)2317 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2318 {
2319 	switch (cap->hwcap_type) {
2320 	case CAP_HWCAP:
2321 		cpu_set_feature(cap->hwcap);
2322 		break;
2323 #ifdef CONFIG_COMPAT
2324 	case CAP_COMPAT_HWCAP:
2325 		compat_elf_hwcap |= (u32)cap->hwcap;
2326 		break;
2327 	case CAP_COMPAT_HWCAP2:
2328 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2329 		break;
2330 #endif
2331 	default:
2332 		WARN_ON(1);
2333 		break;
2334 	}
2335 }
2336 
2337 /* Check if we have a particular HWCAP enabled */
cpus_have_elf_hwcap(const struct arm64_cpu_capabilities * cap)2338 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2339 {
2340 	bool rc;
2341 
2342 	switch (cap->hwcap_type) {
2343 	case CAP_HWCAP:
2344 		rc = cpu_have_feature(cap->hwcap);
2345 		break;
2346 #ifdef CONFIG_COMPAT
2347 	case CAP_COMPAT_HWCAP:
2348 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2349 		break;
2350 	case CAP_COMPAT_HWCAP2:
2351 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2352 		break;
2353 #endif
2354 	default:
2355 		WARN_ON(1);
2356 		rc = false;
2357 	}
2358 
2359 	return rc;
2360 }
2361 
setup_elf_hwcaps(const struct arm64_cpu_capabilities * hwcaps)2362 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2363 {
2364 	/* We support emulation of accesses to CPU ID feature registers */
2365 	cpu_set_named_feature(CPUID);
2366 	for (; hwcaps->matches; hwcaps++)
2367 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2368 			cap_set_elf_hwcap(hwcaps);
2369 }
2370 
update_cpu_capabilities(u16 scope_mask)2371 static void update_cpu_capabilities(u16 scope_mask)
2372 {
2373 	int i;
2374 	const struct arm64_cpu_capabilities *caps;
2375 
2376 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2377 	for (i = 0; i < ARM64_NCAPS; i++) {
2378 		caps = cpu_hwcaps_ptrs[i];
2379 		if (!caps || !(caps->type & scope_mask) ||
2380 		    cpus_have_cap(caps->capability) ||
2381 		    !caps->matches(caps, cpucap_default_scope(caps)))
2382 			continue;
2383 
2384 		if (caps->desc)
2385 			pr_info("detected: %s\n", caps->desc);
2386 		cpus_set_cap(caps->capability);
2387 
2388 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2389 			set_bit(caps->capability, boot_capabilities);
2390 	}
2391 }
2392 
2393 /*
2394  * Enable all the available capabilities on this CPU. The capabilities
2395  * with BOOT_CPU scope are handled separately and hence skipped here.
2396  */
cpu_enable_non_boot_scope_capabilities(void * __unused)2397 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2398 {
2399 	int i;
2400 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2401 
2402 	for_each_available_cap(i) {
2403 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2404 
2405 		if (WARN_ON(!cap))
2406 			continue;
2407 
2408 		if (!(cap->type & non_boot_scope))
2409 			continue;
2410 
2411 		if (cap->cpu_enable)
2412 			cap->cpu_enable(cap);
2413 	}
2414 	return 0;
2415 }
2416 
2417 /*
2418  * Run through the enabled capabilities and enable() it on all active
2419  * CPUs
2420  */
enable_cpu_capabilities(u16 scope_mask)2421 static void __init enable_cpu_capabilities(u16 scope_mask)
2422 {
2423 	int i;
2424 	const struct arm64_cpu_capabilities *caps;
2425 	bool boot_scope;
2426 
2427 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2428 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2429 
2430 	for (i = 0; i < ARM64_NCAPS; i++) {
2431 		unsigned int num;
2432 
2433 		caps = cpu_hwcaps_ptrs[i];
2434 		if (!caps || !(caps->type & scope_mask))
2435 			continue;
2436 		num = caps->capability;
2437 		if (!cpus_have_cap(num))
2438 			continue;
2439 
2440 		/* Ensure cpus_have_const_cap(num) works */
2441 		static_branch_enable(&cpu_hwcap_keys[num]);
2442 
2443 		if (boot_scope && caps->cpu_enable)
2444 			/*
2445 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2446 			 * before any secondary CPU boots. Thus, each secondary
2447 			 * will enable the capability as appropriate via
2448 			 * check_local_cpu_capabilities(). The only exception is
2449 			 * the boot CPU, for which the capability must be
2450 			 * enabled here. This approach avoids costly
2451 			 * stop_machine() calls for this case.
2452 			 */
2453 			caps->cpu_enable(caps);
2454 	}
2455 
2456 	/*
2457 	 * For all non-boot scope capabilities, use stop_machine()
2458 	 * as it schedules the work allowing us to modify PSTATE,
2459 	 * instead of on_each_cpu() which uses an IPI, giving us a
2460 	 * PSTATE that disappears when we return.
2461 	 */
2462 	if (!boot_scope)
2463 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2464 			     NULL, cpu_online_mask);
2465 }
2466 
2467 /*
2468  * Run through the list of capabilities to check for conflicts.
2469  * If the system has already detected a capability, take necessary
2470  * action on this CPU.
2471  */
verify_local_cpu_caps(u16 scope_mask)2472 static void verify_local_cpu_caps(u16 scope_mask)
2473 {
2474 	int i;
2475 	bool cpu_has_cap, system_has_cap;
2476 	const struct arm64_cpu_capabilities *caps;
2477 
2478 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2479 
2480 	for (i = 0; i < ARM64_NCAPS; i++) {
2481 		caps = cpu_hwcaps_ptrs[i];
2482 		if (!caps || !(caps->type & scope_mask))
2483 			continue;
2484 
2485 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2486 		system_has_cap = cpus_have_cap(caps->capability);
2487 
2488 		if (system_has_cap) {
2489 			/*
2490 			 * Check if the new CPU misses an advertised feature,
2491 			 * which is not safe to miss.
2492 			 */
2493 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2494 				break;
2495 			/*
2496 			 * We have to issue cpu_enable() irrespective of
2497 			 * whether the CPU has it or not, as it is enabeld
2498 			 * system wide. It is upto the call back to take
2499 			 * appropriate action on this CPU.
2500 			 */
2501 			if (caps->cpu_enable)
2502 				caps->cpu_enable(caps);
2503 		} else {
2504 			/*
2505 			 * Check if the CPU has this capability if it isn't
2506 			 * safe to have when the system doesn't.
2507 			 */
2508 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2509 				break;
2510 		}
2511 	}
2512 
2513 	if (i < ARM64_NCAPS) {
2514 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2515 			smp_processor_id(), caps->capability,
2516 			caps->desc, system_has_cap, cpu_has_cap);
2517 
2518 		if (cpucap_panic_on_conflict(caps))
2519 			cpu_panic_kernel();
2520 		else
2521 			cpu_die_early();
2522 	}
2523 }
2524 
2525 /*
2526  * Check for CPU features that are used in early boot
2527  * based on the Boot CPU value.
2528  */
check_early_cpu_features(void)2529 static void check_early_cpu_features(void)
2530 {
2531 	verify_cpu_asid_bits();
2532 
2533 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2534 }
2535 
2536 static void
verify_local_elf_hwcaps(const struct arm64_cpu_capabilities * caps)2537 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2538 {
2539 
2540 	for (; caps->matches; caps++)
2541 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2542 			pr_crit("CPU%d: missing HWCAP: %s\n",
2543 					smp_processor_id(), caps->desc);
2544 			cpu_die_early();
2545 		}
2546 }
2547 
verify_sve_features(void)2548 static void verify_sve_features(void)
2549 {
2550 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2551 	u64 zcr = read_zcr_features();
2552 
2553 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2554 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2555 
2556 	if (len < safe_len || sve_verify_vq_map()) {
2557 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2558 			smp_processor_id());
2559 		cpu_die_early();
2560 	}
2561 
2562 	/* Add checks on other ZCR bits here if necessary */
2563 }
2564 
verify_hyp_capabilities(void)2565 static void verify_hyp_capabilities(void)
2566 {
2567 	u64 safe_mmfr1, mmfr0, mmfr1;
2568 	int parange, ipa_max;
2569 	unsigned int safe_vmid_bits, vmid_bits;
2570 
2571 	if (!IS_ENABLED(CONFIG_KVM))
2572 		return;
2573 
2574 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2575 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2576 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2577 
2578 	/* Verify VMID bits */
2579 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2580 	vmid_bits = get_vmid_bits(mmfr1);
2581 	if (vmid_bits < safe_vmid_bits) {
2582 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2583 		cpu_die_early();
2584 	}
2585 
2586 	/* Verify IPA range */
2587 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2588 				ID_AA64MMFR0_PARANGE_SHIFT);
2589 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2590 	if (ipa_max < get_kvm_ipa_limit()) {
2591 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2592 		cpu_die_early();
2593 	}
2594 }
2595 
2596 /*
2597  * Run through the enabled system capabilities and enable() it on this CPU.
2598  * The capabilities were decided based on the available CPUs at the boot time.
2599  * Any new CPU should match the system wide status of the capability. If the
2600  * new CPU doesn't have a capability which the system now has enabled, we
2601  * cannot do anything to fix it up and could cause unexpected failures. So
2602  * we park the CPU.
2603  */
verify_local_cpu_capabilities(void)2604 static void verify_local_cpu_capabilities(void)
2605 {
2606 	/*
2607 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2608 	 * check_early_cpu_features(), as they need to be verified
2609 	 * on all secondary CPUs.
2610 	 */
2611 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2612 
2613 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
2614 
2615 	if (system_supports_32bit_el0())
2616 		verify_local_elf_hwcaps(compat_elf_hwcaps);
2617 
2618 	if (system_supports_sve())
2619 		verify_sve_features();
2620 
2621 	if (is_hyp_mode_available())
2622 		verify_hyp_capabilities();
2623 }
2624 
check_local_cpu_capabilities(void)2625 void check_local_cpu_capabilities(void)
2626 {
2627 	/*
2628 	 * All secondary CPUs should conform to the early CPU features
2629 	 * in use by the kernel based on boot CPU.
2630 	 */
2631 	check_early_cpu_features();
2632 
2633 	/*
2634 	 * If we haven't finalised the system capabilities, this CPU gets
2635 	 * a chance to update the errata work arounds and local features.
2636 	 * Otherwise, this CPU should verify that it has all the system
2637 	 * advertised capabilities.
2638 	 */
2639 	if (!system_capabilities_finalized())
2640 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2641 	else
2642 		verify_local_cpu_capabilities();
2643 }
2644 
setup_boot_cpu_capabilities(void)2645 static void __init setup_boot_cpu_capabilities(void)
2646 {
2647 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2648 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2649 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2650 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2651 }
2652 
this_cpu_has_cap(unsigned int n)2653 bool this_cpu_has_cap(unsigned int n)
2654 {
2655 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2656 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2657 
2658 		if (cap)
2659 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2660 	}
2661 
2662 	return false;
2663 }
2664 
2665 /*
2666  * This helper function is used in a narrow window when,
2667  * - The system wide safe registers are set with all the SMP CPUs and,
2668  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2669  * In all other cases cpus_have_{const_}cap() should be used.
2670  */
__system_matches_cap(unsigned int n)2671 static bool __system_matches_cap(unsigned int n)
2672 {
2673 	if (n < ARM64_NCAPS) {
2674 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2675 
2676 		if (cap)
2677 			return cap->matches(cap, SCOPE_SYSTEM);
2678 	}
2679 	return false;
2680 }
2681 
cpu_set_feature(unsigned int num)2682 void cpu_set_feature(unsigned int num)
2683 {
2684 	WARN_ON(num >= MAX_CPU_FEATURES);
2685 	elf_hwcap |= BIT(num);
2686 }
2687 EXPORT_SYMBOL_GPL(cpu_set_feature);
2688 
cpu_have_feature(unsigned int num)2689 bool cpu_have_feature(unsigned int num)
2690 {
2691 	WARN_ON(num >= MAX_CPU_FEATURES);
2692 	return elf_hwcap & BIT(num);
2693 }
2694 EXPORT_SYMBOL_GPL(cpu_have_feature);
2695 
cpu_get_elf_hwcap(void)2696 unsigned long cpu_get_elf_hwcap(void)
2697 {
2698 	/*
2699 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2700 	 * note that for userspace compatibility we guarantee that bits 62
2701 	 * and 63 will always be returned as 0.
2702 	 */
2703 	return lower_32_bits(elf_hwcap);
2704 }
2705 
cpu_get_elf_hwcap2(void)2706 unsigned long cpu_get_elf_hwcap2(void)
2707 {
2708 	return upper_32_bits(elf_hwcap);
2709 }
2710 
setup_system_capabilities(void)2711 static void __init setup_system_capabilities(void)
2712 {
2713 	/*
2714 	 * We have finalised the system-wide safe feature
2715 	 * registers, finalise the capabilities that depend
2716 	 * on it. Also enable all the available capabilities,
2717 	 * that are not enabled already.
2718 	 */
2719 	update_cpu_capabilities(SCOPE_SYSTEM);
2720 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2721 }
2722 
setup_cpu_features(void)2723 void __init setup_cpu_features(void)
2724 {
2725 	u32 cwg;
2726 
2727 	setup_system_capabilities();
2728 	setup_elf_hwcaps(arm64_elf_hwcaps);
2729 
2730 	if (system_supports_32bit_el0())
2731 		setup_elf_hwcaps(compat_elf_hwcaps);
2732 
2733 	if (system_uses_ttbr0_pan())
2734 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2735 
2736 	sve_setup();
2737 	minsigstksz_setup();
2738 
2739 	/* Advertise that we have computed the system capabilities */
2740 	finalize_system_capabilities();
2741 
2742 	/*
2743 	 * Check for sane CTR_EL0.CWG value.
2744 	 */
2745 	cwg = cache_type_cwg();
2746 	if (!cwg)
2747 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2748 			ARCH_DMA_MINALIGN);
2749 }
2750 
2751 static bool __maybe_unused
cpufeature_pan_not_uao(const struct arm64_cpu_capabilities * entry,int __unused)2752 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
2753 {
2754 	return (__system_matches_cap(ARM64_HAS_PAN) && !__system_matches_cap(ARM64_HAS_UAO));
2755 }
2756 
cpu_enable_cnp(struct arm64_cpu_capabilities const * cap)2757 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2758 {
2759 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2760 }
2761 
2762 /*
2763  * We emulate only the following system register space.
2764  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2765  * See Table C5-6 System instruction encodings for System register accesses,
2766  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2767  */
is_emulated(u32 id)2768 static inline bool __attribute_const__ is_emulated(u32 id)
2769 {
2770 	return (sys_reg_Op0(id) == 0x3 &&
2771 		sys_reg_CRn(id) == 0x0 &&
2772 		sys_reg_Op1(id) == 0x0 &&
2773 		(sys_reg_CRm(id) == 0 ||
2774 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2775 }
2776 
2777 /*
2778  * With CRm == 0, reg should be one of :
2779  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2780  */
emulate_id_reg(u32 id,u64 * valp)2781 static inline int emulate_id_reg(u32 id, u64 *valp)
2782 {
2783 	switch (id) {
2784 	case SYS_MIDR_EL1:
2785 		*valp = read_cpuid_id();
2786 		break;
2787 	case SYS_MPIDR_EL1:
2788 		*valp = SYS_MPIDR_SAFE_VAL;
2789 		break;
2790 	case SYS_REVIDR_EL1:
2791 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2792 		*valp = 0;
2793 		break;
2794 	default:
2795 		return -EINVAL;
2796 	}
2797 
2798 	return 0;
2799 }
2800 
emulate_sys_reg(u32 id,u64 * valp)2801 static int emulate_sys_reg(u32 id, u64 *valp)
2802 {
2803 	struct arm64_ftr_reg *regp;
2804 
2805 	if (!is_emulated(id))
2806 		return -EINVAL;
2807 
2808 	if (sys_reg_CRm(id) == 0)
2809 		return emulate_id_reg(id, valp);
2810 
2811 	regp = get_arm64_ftr_reg_nowarn(id);
2812 	if (regp)
2813 		*valp = arm64_ftr_reg_user_value(regp);
2814 	else
2815 		/*
2816 		 * The untracked registers are either IMPLEMENTATION DEFINED
2817 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2818 		 */
2819 		*valp = 0;
2820 	return 0;
2821 }
2822 
do_emulate_mrs(struct pt_regs * regs,u32 sys_reg,u32 rt)2823 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2824 {
2825 	int rc;
2826 	u64 val;
2827 
2828 	rc = emulate_sys_reg(sys_reg, &val);
2829 	if (!rc) {
2830 		pt_regs_write_reg(regs, rt, val);
2831 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2832 	}
2833 	return rc;
2834 }
2835 
emulate_mrs(struct pt_regs * regs,u32 insn)2836 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2837 {
2838 	u32 sys_reg, rt;
2839 
2840 	/*
2841 	 * sys_reg values are defined as used in mrs/msr instruction.
2842 	 * shift the imm value to get the encoding.
2843 	 */
2844 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2845 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2846 	return do_emulate_mrs(regs, sys_reg, rt);
2847 }
2848 
2849 static struct undef_hook mrs_hook = {
2850 	.instr_mask = 0xfff00000,
2851 	.instr_val  = 0xd5300000,
2852 	.pstate_mask = PSR_AA32_MODE_MASK,
2853 	.pstate_val = PSR_MODE_EL0t,
2854 	.fn = emulate_mrs,
2855 };
2856 
enable_mrs_emulation(void)2857 static int __init enable_mrs_emulation(void)
2858 {
2859 	register_undef_hook(&mrs_hook);
2860 	return 0;
2861 }
2862 
2863 core_initcall(enable_mrs_emulation);
2864 
cpu_show_meltdown(struct device * dev,struct device_attribute * attr,char * buf)2865 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
2866 			  char *buf)
2867 {
2868 	if (__meltdown_safe)
2869 		return sprintf(buf, "Not affected\n");
2870 
2871 	if (arm64_kernel_unmapped_at_el0())
2872 		return sprintf(buf, "Mitigation: PTI\n");
2873 
2874 	return sprintf(buf, "Vulnerable\n");
2875 }
2876