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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/hwcap.h>
80 #include <asm/mmu_context.h>
81 #include <asm/mte.h>
82 #include <asm/processor.h>
83 #include <asm/sysreg.h>
84 #include <asm/traps.h>
85 #include <asm/vectors.h>
86 #include <asm/virt.h>
87 
88 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
89 static unsigned long elf_hwcap __read_mostly;
90 
91 #ifdef CONFIG_COMPAT
92 #define COMPAT_ELF_HWCAP_DEFAULT	\
93 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
94 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
95 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\
96 				 COMPAT_HWCAP_LPAE)
97 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
98 unsigned int compat_elf_hwcap2 __read_mostly;
99 #endif
100 
101 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
102 EXPORT_SYMBOL(cpu_hwcaps);
103 static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS];
104 
105 /* Need also bit for ARM64_CB_PATCH */
106 DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
107 
108 bool arm64_use_ng_mappings = false;
109 EXPORT_SYMBOL(arm64_use_ng_mappings);
110 
111 DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
112 
113 /*
114  * Flag to indicate if we have computed the system wide
115  * capabilities based on the boot time active CPUs. This
116  * will be used to determine if a new booting CPU should
117  * go through the verification process to make sure that it
118  * supports the system capabilities, without using a hotplug
119  * notifier. This is also used to decide if we could use
120  * the fast path for checking constant CPU caps.
121  */
122 DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready);
123 EXPORT_SYMBOL(arm64_const_caps_ready);
finalize_system_capabilities(void)124 static inline void finalize_system_capabilities(void)
125 {
126 	static_branch_enable(&arm64_const_caps_ready);
127 }
128 
dump_cpu_features(void)129 void dump_cpu_features(void)
130 {
131 	/* file-wide pr_fmt adds "CPU features: " prefix */
132 	pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps);
133 }
134 
135 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
136 EXPORT_SYMBOL(cpu_hwcap_keys);
137 
138 #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
139 	{						\
140 		.sign = SIGNED,				\
141 		.visible = VISIBLE,			\
142 		.strict = STRICT,			\
143 		.type = TYPE,				\
144 		.shift = SHIFT,				\
145 		.width = WIDTH,				\
146 		.safe_val = SAFE_VAL,			\
147 	}
148 
149 /* Define a feature with unsigned values */
150 #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
151 	__ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
152 
153 /* Define a feature with a signed value */
154 #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \
155 	__ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL)
156 
157 #define ARM64_FTR_END					\
158 	{						\
159 		.width = 0,				\
160 	}
161 
162 /* meta feature for alternatives */
163 static bool __maybe_unused
164 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused);
165 
166 static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap);
167 
168 static bool __system_matches_cap(unsigned int n);
169 
170 /*
171  * NOTE: Any changes to the visibility of features should be kept in
172  * sync with the documentation of the CPU feature register ABI.
173  */
174 static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
175 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0),
176 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0),
177 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0),
178 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0),
179 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0),
180 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
181 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
182 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
183 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
184 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
185 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
186 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0),
187 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0),
188 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0),
189 	ARM64_FTR_END,
190 };
191 
192 static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
193 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0),
194 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0),
195 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0),
196 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0),
197 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0),
198 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0),
199 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
200 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0),
201 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
202 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0),
203 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0),
204 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
205 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
206 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
207 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_API_SHIFT, 4, 0),
208 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
209 		       FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_APA_SHIFT, 4, 0),
210 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0),
211 	ARM64_FTR_END,
212 };
213 
214 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
215 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
216 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
217 	ARM64_FTR_END,
218 };
219 
220 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
221 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
222 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
223 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0),
224 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0),
225 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0),
226 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0),
227 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
228 				   FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0),
229 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0),
230 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0),
231 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI),
232 	S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI),
233 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0),
234 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0),
235 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY),
236 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY),
237 	ARM64_FTR_END,
238 };
239 
240 static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = {
241 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0),
242 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0),
243 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_MTE),
244 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MTE_SHIFT, 4, ID_AA64PFR1_MTE_NI),
245 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI),
246 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI),
247 				    FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0),
248 	ARM64_FTR_END,
249 };
250 
251 static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
252 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
253 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0),
254 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
255 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0),
256 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
257 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0),
258 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
259 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0),
260 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
261 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0),
262 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
263 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0),
264 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
265 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0),
266 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
267 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0),
268 	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE),
269 		       FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0),
270 	ARM64_FTR_END,
271 };
272 
273 static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
274 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
275 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
276 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
277 	/*
278 	 * Page size not being supported at Stage-2 is not fatal. You
279 	 * just give up KVM if PAGE_SIZE isn't supported there. Go fix
280 	 * your favourite nesting hypervisor.
281 	 *
282 	 * There is a small corner case where the hypervisor explicitly
283 	 * advertises a given granule size at Stage-2 (value 2) on some
284 	 * vCPUs, and uses the fallback to Stage-1 (value 0) for other
285 	 * vCPUs. Although this is not forbidden by the architecture, it
286 	 * indicates that the hypervisor is being silly (or buggy).
287 	 *
288 	 * We make no effort to cope with this and pretend that if these
289 	 * fields are inconsistent across vCPUs, then it isn't worth
290 	 * trying to bring KVM up.
291 	 */
292 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_2_SHIFT, 4, 1),
293 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_2_SHIFT, 4, 1),
294 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_2_SHIFT, 4, 1),
295 	/*
296 	 * We already refuse to boot CPUs that don't support our configured
297 	 * page size, so we can only detect mismatches for a page size other
298 	 * than the one we're currently using. Unfortunately, SoCs like this
299 	 * exist in the wild so, even though we don't like it, we'll have to go
300 	 * along with it and treat them as non-strict.
301 	 */
302 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
303 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
304 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
305 
306 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
307 	/* Linux shouldn't care about secure memory */
308 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
309 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0),
310 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0),
311 	/*
312 	 * Differing PARange is fine as long as all peripherals and memory are mapped
313 	 * within the minimum PARange of all CPUs
314 	 */
315 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0),
316 	ARM64_FTR_END,
317 };
318 
319 static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
320 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
321 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
322 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
323 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
324 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64MMFR1_SPECSEI_SHIFT, 4, 0),
325 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0),
326 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0),
327 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0),
328 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0),
329 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0),
330 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0),
331 	ARM64_FTR_END,
332 };
333 
334 static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
335 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
336 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_EVT_SHIFT, 4, 0),
337 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_BBM_SHIFT, 4, 0),
338 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
339 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
340 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IDS_SHIFT, 4, 0),
341 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
342 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_ST_SHIFT, 4, 0),
343 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_NV_SHIFT, 4, 0),
344 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CCIDX_SHIFT, 4, 0),
345 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
346 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
347 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
348 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
349 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
350 	ARM64_FTR_END,
351 };
352 
353 static const struct arm64_ftr_bits ftr_ctr[] = {
354 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
355 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
356 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
357 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
358 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
359 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
360 	/*
361 	 * Linux can handle differing I-cache policies. Userspace JITs will
362 	 * make use of *minLine.
363 	 * If we have differing I-cache policies, report it as the weakest - VIPT.
364 	 */
365 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, CTR_L1IP_SHIFT, 2, ICACHE_POLICY_VIPT),	/* L1Ip */
366 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0),
367 	ARM64_FTR_END,
368 };
369 
370 struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = {
371 	.name		= "SYS_CTR_EL0",
372 	.ftr_bits	= ftr_ctr
373 };
374 
375 static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
376 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_INNERSHR_SHIFT, 4, 0xf),
377 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_FCSE_SHIFT, 4, 0),
378 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_MMFR0_AUXREG_SHIFT, 4, 0),
379 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_TCM_SHIFT, 4, 0),
380 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_SHARELVL_SHIFT, 4, 0),
381 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_OUTERSHR_SHIFT, 4, 0xf),
382 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_PMSA_SHIFT, 4, 0),
383 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR0_VMSA_SHIFT, 4, 0),
384 	ARM64_FTR_END,
385 };
386 
387 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
388 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_DOUBLELOCK_SHIFT, 4, 0),
389 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0),
390 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0),
391 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0),
392 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0),
393 	/*
394 	 * We can instantiate multiple PMU instances with different levels
395 	 * of support.
396 	 */
397 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0),
398 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6),
399 	ARM64_FTR_END,
400 };
401 
402 static const struct arm64_ftr_bits ftr_mvfr2[] = {
403 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_FPMISC_SHIFT, 4, 0),
404 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR2_SIMDMISC_SHIFT, 4, 0),
405 	ARM64_FTR_END,
406 };
407 
408 static const struct arm64_ftr_bits ftr_dczid[] = {
409 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, DCZID_DZP_SHIFT, 1, 1),
410 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, DCZID_BS_SHIFT, 4, 0),
411 	ARM64_FTR_END,
412 };
413 
414 static const struct arm64_ftr_bits ftr_id_isar0[] = {
415 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0),
416 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0),
417 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0),
418 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0),
419 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0),
420 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0),
421 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0),
422 	ARM64_FTR_END,
423 };
424 
425 static const struct arm64_ftr_bits ftr_id_isar5[] = {
426 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0),
427 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0),
428 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0),
429 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0),
430 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0),
431 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0),
432 	ARM64_FTR_END,
433 };
434 
435 static const struct arm64_ftr_bits ftr_id_mmfr4[] = {
436 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0),
437 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0),
438 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0),
439 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0),
440 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0),
441 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0),
442 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_AC2_SHIFT, 4, 0),
443 
444 	/*
445 	 * SpecSEI = 1 indicates that the PE might generate an SError on an
446 	 * external abort on speculative read. It is safe to assume that an
447 	 * SError might be generated than it will not be. Hence it has been
448 	 * classified as FTR_HIGHER_SAFE.
449 	 */
450 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0),
451 	ARM64_FTR_END,
452 };
453 
454 static const struct arm64_ftr_bits ftr_id_isar4[] = {
455 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0),
456 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0),
457 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0),
458 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0),
459 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0),
460 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0),
461 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0),
462 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0),
463 	ARM64_FTR_END,
464 };
465 
466 static const struct arm64_ftr_bits ftr_id_mmfr5[] = {
467 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0),
468 	ARM64_FTR_END,
469 };
470 
471 static const struct arm64_ftr_bits ftr_id_isar6[] = {
472 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0),
473 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0),
474 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0),
475 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0),
476 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0),
477 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0),
478 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0),
479 	ARM64_FTR_END,
480 };
481 
482 static const struct arm64_ftr_bits ftr_id_pfr0[] = {
483 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
484 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
485 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0),
486 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0),
487 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0),
488 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0),
489 	ARM64_FTR_END,
490 };
491 
492 static const struct arm64_ftr_bits ftr_id_pfr1[] = {
493 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0),
494 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0),
495 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0),
496 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0),
497 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0),
498 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0),
499 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0),
500 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0),
501 	ARM64_FTR_END,
502 };
503 
504 static const struct arm64_ftr_bits ftr_id_pfr2[] = {
505 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
506 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
507 	ARM64_FTR_END,
508 };
509 
510 static const struct arm64_ftr_bits ftr_id_dfr0[] = {
511 	/* [31:28] TraceFilt */
512 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_DFR0_PERFMON_SHIFT, 4, 0),
513 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MPROFDBG_SHIFT, 4, 0),
514 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPTRC_SHIFT, 4, 0),
515 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPTRC_SHIFT, 4, 0),
516 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_MMAPDBG_SHIFT, 4, 0),
517 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPSDBG_SHIFT, 4, 0),
518 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_COPDBG_SHIFT, 4, 0),
519 	ARM64_FTR_END,
520 };
521 
522 static const struct arm64_ftr_bits ftr_id_dfr1[] = {
523 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0),
524 	ARM64_FTR_END,
525 };
526 
527 static const struct arm64_ftr_bits ftr_zcr[] = {
528 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE,
529 		ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0),	/* LEN */
530 	ARM64_FTR_END,
531 };
532 
533 /*
534  * Common ftr bits for a 32bit register with all hidden, strict
535  * attributes, with 4bit feature fields and a default safe value of
536  * 0. Covers the following 32bit registers:
537  * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1]
538  */
539 static const struct arm64_ftr_bits ftr_generic_32bits[] = {
540 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
541 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0),
542 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
543 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),
544 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0),
545 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0),
546 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0),
547 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),
548 	ARM64_FTR_END,
549 };
550 
551 /* Table for a single 32bit feature value */
552 static const struct arm64_ftr_bits ftr_single32[] = {
553 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0),
554 	ARM64_FTR_END,
555 };
556 
557 static const struct arm64_ftr_bits ftr_raz[] = {
558 	ARM64_FTR_END,
559 };
560 
561 #define ARM64_FTR_REG(id, table) {		\
562 	.sys_id = id,				\
563 	.reg = 	&(struct arm64_ftr_reg){	\
564 		.name = #id,			\
565 		.ftr_bits = &((table)[0]),	\
566 	}}
567 
568 static const struct __ftr_reg_entry {
569 	u32			sys_id;
570 	struct arm64_ftr_reg 	*reg;
571 } arm64_ftr_regs[] = {
572 
573 	/* Op1 = 0, CRn = 0, CRm = 1 */
574 	ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0),
575 	ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1),
576 	ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0),
577 	ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0),
578 	ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits),
579 	ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits),
580 	ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits),
581 
582 	/* Op1 = 0, CRn = 0, CRm = 2 */
583 	ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0),
584 	ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits),
585 	ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits),
586 	ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits),
587 	ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4),
588 	ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5),
589 	ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4),
590 	ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6),
591 
592 	/* Op1 = 0, CRn = 0, CRm = 3 */
593 	ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
594 	ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
595 	ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
596 	ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),
597 	ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1),
598 	ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5),
599 
600 	/* Op1 = 0, CRn = 0, CRm = 4 */
601 	ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
602 	ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1),
603 	ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0),
604 
605 	/* Op1 = 0, CRn = 0, CRm = 5 */
606 	ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0),
607 	ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz),
608 
609 	/* Op1 = 0, CRn = 0, CRm = 6 */
610 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
611 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
612 	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
613 
614 	/* Op1 = 0, CRn = 0, CRm = 7 */
615 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
616 	ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1),
617 	ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2),
618 
619 	/* Op1 = 0, CRn = 1, CRm = 2 */
620 	ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr),
621 
622 	/* Op1 = 3, CRn = 0, CRm = 0 */
623 	{ SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 },
624 	ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid),
625 
626 	/* Op1 = 3, CRn = 14, CRm = 0 */
627 	ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32),
628 };
629 
search_cmp_ftr_reg(const void * id,const void * regp)630 static int search_cmp_ftr_reg(const void *id, const void *regp)
631 {
632 	return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id;
633 }
634 
635 /*
636  * get_arm64_ftr_reg_nowarn - Looks up a feature register entry using
637  * its sys_reg() encoding. With the array arm64_ftr_regs sorted in the
638  * ascending order of sys_id, we use binary search to find a matching
639  * entry.
640  *
641  * returns - Upon success,  matching ftr_reg entry for id.
642  *         - NULL on failure. It is upto the caller to decide
643  *	     the impact of a failure.
644  */
get_arm64_ftr_reg_nowarn(u32 sys_id)645 static struct arm64_ftr_reg *get_arm64_ftr_reg_nowarn(u32 sys_id)
646 {
647 	const struct __ftr_reg_entry *ret;
648 
649 	ret = bsearch((const void *)(unsigned long)sys_id,
650 			arm64_ftr_regs,
651 			ARRAY_SIZE(arm64_ftr_regs),
652 			sizeof(arm64_ftr_regs[0]),
653 			search_cmp_ftr_reg);
654 	if (ret)
655 		return ret->reg;
656 	return NULL;
657 }
658 
659 /*
660  * get_arm64_ftr_reg - Looks up a feature register entry using
661  * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
662  *
663  * returns - Upon success,  matching ftr_reg entry for id.
664  *         - NULL on failure but with an WARN_ON().
665  */
get_arm64_ftr_reg(u32 sys_id)666 static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
667 {
668 	struct arm64_ftr_reg *reg;
669 
670 	reg = get_arm64_ftr_reg_nowarn(sys_id);
671 
672 	/*
673 	 * Requesting a non-existent register search is an error. Warn
674 	 * and let the caller handle it.
675 	 */
676 	WARN_ON(!reg);
677 	return reg;
678 }
679 
arm64_ftr_set_value(const struct arm64_ftr_bits * ftrp,s64 reg,s64 ftr_val)680 static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
681 			       s64 ftr_val)
682 {
683 	u64 mask = arm64_ftr_mask(ftrp);
684 
685 	reg &= ~mask;
686 	reg |= (ftr_val << ftrp->shift) & mask;
687 	return reg;
688 }
689 
arm64_ftr_safe_value(const struct arm64_ftr_bits * ftrp,s64 new,s64 cur)690 static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
691 				s64 cur)
692 {
693 	s64 ret = 0;
694 
695 	switch (ftrp->type) {
696 	case FTR_EXACT:
697 		ret = ftrp->safe_val;
698 		break;
699 	case FTR_LOWER_SAFE:
700 		ret = new < cur ? new : cur;
701 		break;
702 	case FTR_HIGHER_OR_ZERO_SAFE:
703 		if (!cur || !new)
704 			break;
705 		fallthrough;
706 	case FTR_HIGHER_SAFE:
707 		ret = new > cur ? new : cur;
708 		break;
709 	default:
710 		BUG();
711 	}
712 
713 	return ret;
714 }
715 
sort_ftr_regs(void)716 static void __init sort_ftr_regs(void)
717 {
718 	unsigned int i;
719 
720 	for (i = 0; i < ARRAY_SIZE(arm64_ftr_regs); i++) {
721 		const struct arm64_ftr_reg *ftr_reg = arm64_ftr_regs[i].reg;
722 		const struct arm64_ftr_bits *ftr_bits = ftr_reg->ftr_bits;
723 		unsigned int j = 0;
724 
725 		/*
726 		 * Features here must be sorted in descending order with respect
727 		 * to their shift values and should not overlap with each other.
728 		 */
729 		for (; ftr_bits->width != 0; ftr_bits++, j++) {
730 			unsigned int width = ftr_reg->ftr_bits[j].width;
731 			unsigned int shift = ftr_reg->ftr_bits[j].shift;
732 			unsigned int prev_shift;
733 
734 			WARN((shift  + width) > 64,
735 				"%s has invalid feature at shift %d\n",
736 				ftr_reg->name, shift);
737 
738 			/*
739 			 * Skip the first feature. There is nothing to
740 			 * compare against for now.
741 			 */
742 			if (j == 0)
743 				continue;
744 
745 			prev_shift = ftr_reg->ftr_bits[j - 1].shift;
746 			WARN((shift + width) > prev_shift,
747 				"%s has feature overlap at shift %d\n",
748 				ftr_reg->name, shift);
749 		}
750 
751 		/*
752 		 * Skip the first register. There is nothing to
753 		 * compare against for now.
754 		 */
755 		if (i == 0)
756 			continue;
757 		/*
758 		 * Registers here must be sorted in ascending order with respect
759 		 * to sys_id for subsequent binary search in get_arm64_ftr_reg()
760 		 * to work correctly.
761 		 */
762 		BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id);
763 	}
764 }
765 
766 /*
767  * Initialise the CPU feature register from Boot CPU values.
768  * Also initiliases the strict_mask for the register.
769  * Any bits that are not covered by an arm64_ftr_bits entry are considered
770  * RES0 for the system-wide value, and must strictly match.
771  */
init_cpu_ftr_reg(u32 sys_reg,u64 new)772 static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
773 {
774 	u64 val = 0;
775 	u64 strict_mask = ~0x0ULL;
776 	u64 user_mask = 0;
777 	u64 valid_mask = 0;
778 
779 	const struct arm64_ftr_bits *ftrp;
780 	struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
781 
782 	if (!reg)
783 		return;
784 
785 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
786 		u64 ftr_mask = arm64_ftr_mask(ftrp);
787 		s64 ftr_new = arm64_ftr_value(ftrp, new);
788 
789 		val = arm64_ftr_set_value(ftrp, val, ftr_new);
790 
791 		valid_mask |= ftr_mask;
792 		if (!ftrp->strict)
793 			strict_mask &= ~ftr_mask;
794 		if (ftrp->visible)
795 			user_mask |= ftr_mask;
796 		else
797 			reg->user_val = arm64_ftr_set_value(ftrp,
798 							    reg->user_val,
799 							    ftrp->safe_val);
800 	}
801 
802 	val &= valid_mask;
803 
804 	reg->sys_val = val;
805 	reg->strict_mask = strict_mask;
806 	reg->user_mask = user_mask;
807 }
808 
809 extern const struct arm64_cpu_capabilities arm64_errata[];
810 static const struct arm64_cpu_capabilities arm64_features[];
811 
812 static void __init
init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities * caps)813 init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps)
814 {
815 	for (; caps->matches; caps++) {
816 		if (WARN(caps->capability >= ARM64_NCAPS,
817 			"Invalid capability %d\n", caps->capability))
818 			continue;
819 		if (WARN(cpu_hwcaps_ptrs[caps->capability],
820 			"Duplicate entry for capability %d\n",
821 			caps->capability))
822 			continue;
823 		cpu_hwcaps_ptrs[caps->capability] = caps;
824 	}
825 }
826 
init_cpu_hwcaps_indirect_list(void)827 static void __init init_cpu_hwcaps_indirect_list(void)
828 {
829 	init_cpu_hwcaps_indirect_list_from_array(arm64_features);
830 	init_cpu_hwcaps_indirect_list_from_array(arm64_errata);
831 }
832 
833 static void __init setup_boot_cpu_capabilities(void);
834 
init_cpu_features(struct cpuinfo_arm64 * info)835 void __init init_cpu_features(struct cpuinfo_arm64 *info)
836 {
837 	/* Before we start using the tables, make sure it is sorted */
838 	sort_ftr_regs();
839 
840 	init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr);
841 	init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid);
842 	init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq);
843 	init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0);
844 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
845 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
846 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
847 	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
848 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
849 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
850 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
851 	init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0);
852 	init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1);
853 	init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0);
854 
855 	if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) {
856 		init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0);
857 		init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1);
858 		init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0);
859 		init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1);
860 		init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2);
861 		init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3);
862 		init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4);
863 		init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5);
864 		init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6);
865 		init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0);
866 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
867 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
868 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
869 		init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
870 		init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
871 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
872 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
873 		init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
874 		init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
875 		init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
876 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
877 	}
878 
879 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
880 		init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr);
881 		sve_init_vq_map();
882 	}
883 
884 	/*
885 	 * Initialize the indirect array of CPU hwcaps capabilities pointers
886 	 * before we handle the boot CPU below.
887 	 */
888 	init_cpu_hwcaps_indirect_list();
889 
890 	/*
891 	 * Detect and enable early CPU capabilities based on the boot CPU,
892 	 * after we have initialised the CPU feature infrastructure.
893 	 */
894 	setup_boot_cpu_capabilities();
895 }
896 
update_cpu_ftr_reg(struct arm64_ftr_reg * reg,u64 new)897 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
898 {
899 	const struct arm64_ftr_bits *ftrp;
900 
901 	for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
902 		s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val);
903 		s64 ftr_new = arm64_ftr_value(ftrp, new);
904 
905 		if (ftr_cur == ftr_new)
906 			continue;
907 		/* Find a safe value */
908 		ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur);
909 		reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new);
910 	}
911 
912 }
913 
check_update_ftr_reg(u32 sys_id,int cpu,u64 val,u64 boot)914 static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
915 {
916 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
917 
918 	if (!regp)
919 		return 0;
920 
921 	update_cpu_ftr_reg(regp, val);
922 	if ((boot & regp->strict_mask) == (val & regp->strict_mask))
923 		return 0;
924 	pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n",
925 			regp->name, boot, cpu, val);
926 	return 1;
927 }
928 
relax_cpu_ftr_reg(u32 sys_id,int field)929 static void relax_cpu_ftr_reg(u32 sys_id, int field)
930 {
931 	const struct arm64_ftr_bits *ftrp;
932 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
933 
934 	if (!regp)
935 		return;
936 
937 	for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) {
938 		if (ftrp->shift == field) {
939 			regp->strict_mask &= ~arm64_ftr_mask(ftrp);
940 			break;
941 		}
942 	}
943 
944 	/* Bogus field? */
945 	WARN_ON(!ftrp->width);
946 }
947 
update_32bit_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)948 static int update_32bit_cpu_features(int cpu, struct cpuinfo_arm64 *info,
949 				     struct cpuinfo_arm64 *boot)
950 {
951 	int taint = 0;
952 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
953 
954 	/*
955 	 * If we don't have AArch32 at all then skip the checks entirely
956 	 * as the register values may be UNKNOWN and we're not going to be
957 	 * using them for anything.
958 	 */
959 	if (!id_aa64pfr0_32bit_el0(pfr0))
960 		return taint;
961 
962 	/*
963 	 * If we don't have AArch32 at EL1, then relax the strictness of
964 	 * EL1-dependent register fields to avoid spurious sanity check fails.
965 	 */
966 	if (!id_aa64pfr0_32bit_el1(pfr0)) {
967 		relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT);
968 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT);
969 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT);
970 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT);
971 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT);
972 		relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT);
973 	}
974 
975 	taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu,
976 				      info->reg_id_dfr0, boot->reg_id_dfr0);
977 	taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu,
978 				      info->reg_id_dfr1, boot->reg_id_dfr1);
979 	taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu,
980 				      info->reg_id_isar0, boot->reg_id_isar0);
981 	taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu,
982 				      info->reg_id_isar1, boot->reg_id_isar1);
983 	taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu,
984 				      info->reg_id_isar2, boot->reg_id_isar2);
985 	taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu,
986 				      info->reg_id_isar3, boot->reg_id_isar3);
987 	taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu,
988 				      info->reg_id_isar4, boot->reg_id_isar4);
989 	taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu,
990 				      info->reg_id_isar5, boot->reg_id_isar5);
991 	taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu,
992 				      info->reg_id_isar6, boot->reg_id_isar6);
993 
994 	/*
995 	 * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
996 	 * ACTLR formats could differ across CPUs and therefore would have to
997 	 * be trapped for virtualization anyway.
998 	 */
999 	taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu,
1000 				      info->reg_id_mmfr0, boot->reg_id_mmfr0);
1001 	taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu,
1002 				      info->reg_id_mmfr1, boot->reg_id_mmfr1);
1003 	taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu,
1004 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
1005 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
1006 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
1007 	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
1008 				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
1009 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
1010 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
1011 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
1012 				      info->reg_id_pfr0, boot->reg_id_pfr0);
1013 	taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
1014 				      info->reg_id_pfr1, boot->reg_id_pfr1);
1015 	taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
1016 				      info->reg_id_pfr2, boot->reg_id_pfr2);
1017 	taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
1018 				      info->reg_mvfr0, boot->reg_mvfr0);
1019 	taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
1020 				      info->reg_mvfr1, boot->reg_mvfr1);
1021 	taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu,
1022 				      info->reg_mvfr2, boot->reg_mvfr2);
1023 
1024 	return taint;
1025 }
1026 
1027 /*
1028  * Update system wide CPU feature registers with the values from a
1029  * non-boot CPU. Also performs SANITY checks to make sure that there
1030  * aren't any insane variations from that of the boot CPU.
1031  */
update_cpu_features(int cpu,struct cpuinfo_arm64 * info,struct cpuinfo_arm64 * boot)1032 void update_cpu_features(int cpu,
1033 			 struct cpuinfo_arm64 *info,
1034 			 struct cpuinfo_arm64 *boot)
1035 {
1036 	int taint = 0;
1037 
1038 	/*
1039 	 * The kernel can handle differing I-cache policies, but otherwise
1040 	 * caches should look identical. Userspace JITs will make use of
1041 	 * *minLine.
1042 	 */
1043 	taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu,
1044 				      info->reg_ctr, boot->reg_ctr);
1045 
1046 	/*
1047 	 * Userspace may perform DC ZVA instructions. Mismatched block sizes
1048 	 * could result in too much or too little memory being zeroed if a
1049 	 * process is preempted and migrated between CPUs.
1050 	 */
1051 	taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu,
1052 				      info->reg_dczid, boot->reg_dczid);
1053 
1054 	/* If different, timekeeping will be broken (especially with KVM) */
1055 	taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu,
1056 				      info->reg_cntfrq, boot->reg_cntfrq);
1057 
1058 	/*
1059 	 * The kernel uses self-hosted debug features and expects CPUs to
1060 	 * support identical debug features. We presently need CTX_CMPs, WRPs,
1061 	 * and BRPs to be identical.
1062 	 * ID_AA64DFR1 is currently RES0.
1063 	 */
1064 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu,
1065 				      info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0);
1066 	taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu,
1067 				      info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1);
1068 	/*
1069 	 * Even in big.LITTLE, processors should be identical instruction-set
1070 	 * wise.
1071 	 */
1072 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu,
1073 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
1074 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
1075 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
1076 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
1077 				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
1078 
1079 	/*
1080 	 * Differing PARange support is fine as long as all peripherals and
1081 	 * memory are mapped within the minimum PARange of all CPUs.
1082 	 * Linux should not care about secure memory.
1083 	 */
1084 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu,
1085 				      info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0);
1086 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu,
1087 				      info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1);
1088 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu,
1089 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
1090 
1091 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
1092 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);
1093 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu,
1094 				      info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1);
1095 
1096 	taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu,
1097 				      info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0);
1098 
1099 	if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) {
1100 		taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu,
1101 					info->reg_zcr, boot->reg_zcr);
1102 
1103 		/* Probe vector lengths, unless we already gave up on SVE */
1104 		if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) &&
1105 		    !system_capabilities_finalized())
1106 			sve_update_vq_map();
1107 	}
1108 
1109 	/*
1110 	 * This relies on a sanitised view of the AArch64 ID registers
1111 	 * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last.
1112 	 */
1113 	taint |= update_32bit_cpu_features(cpu, info, boot);
1114 
1115 	/*
1116 	 * Mismatched CPU features are a recipe for disaster. Don't even
1117 	 * pretend to support them.
1118 	 */
1119 	if (taint) {
1120 		pr_warn_once("Unsupported CPU feature variation detected.\n");
1121 		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1122 	}
1123 }
1124 
read_sanitised_ftr_reg(u32 id)1125 u64 read_sanitised_ftr_reg(u32 id)
1126 {
1127 	struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id);
1128 
1129 	if (!regp)
1130 		return 0;
1131 	return regp->sys_val;
1132 }
1133 EXPORT_SYMBOL_GPL(read_sanitised_ftr_reg);
1134 
1135 #define read_sysreg_case(r)	\
1136 	case r:		return read_sysreg_s(r)
1137 
1138 /*
1139  * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated.
1140  * Read the system register on the current CPU
1141  */
__read_sysreg_by_encoding(u32 sys_id)1142 static u64 __read_sysreg_by_encoding(u32 sys_id)
1143 {
1144 	switch (sys_id) {
1145 	read_sysreg_case(SYS_ID_PFR0_EL1);
1146 	read_sysreg_case(SYS_ID_PFR1_EL1);
1147 	read_sysreg_case(SYS_ID_PFR2_EL1);
1148 	read_sysreg_case(SYS_ID_DFR0_EL1);
1149 	read_sysreg_case(SYS_ID_DFR1_EL1);
1150 	read_sysreg_case(SYS_ID_MMFR0_EL1);
1151 	read_sysreg_case(SYS_ID_MMFR1_EL1);
1152 	read_sysreg_case(SYS_ID_MMFR2_EL1);
1153 	read_sysreg_case(SYS_ID_MMFR3_EL1);
1154 	read_sysreg_case(SYS_ID_MMFR4_EL1);
1155 	read_sysreg_case(SYS_ID_MMFR5_EL1);
1156 	read_sysreg_case(SYS_ID_ISAR0_EL1);
1157 	read_sysreg_case(SYS_ID_ISAR1_EL1);
1158 	read_sysreg_case(SYS_ID_ISAR2_EL1);
1159 	read_sysreg_case(SYS_ID_ISAR3_EL1);
1160 	read_sysreg_case(SYS_ID_ISAR4_EL1);
1161 	read_sysreg_case(SYS_ID_ISAR5_EL1);
1162 	read_sysreg_case(SYS_ID_ISAR6_EL1);
1163 	read_sysreg_case(SYS_MVFR0_EL1);
1164 	read_sysreg_case(SYS_MVFR1_EL1);
1165 	read_sysreg_case(SYS_MVFR2_EL1);
1166 
1167 	read_sysreg_case(SYS_ID_AA64PFR0_EL1);
1168 	read_sysreg_case(SYS_ID_AA64PFR1_EL1);
1169 	read_sysreg_case(SYS_ID_AA64ZFR0_EL1);
1170 	read_sysreg_case(SYS_ID_AA64DFR0_EL1);
1171 	read_sysreg_case(SYS_ID_AA64DFR1_EL1);
1172 	read_sysreg_case(SYS_ID_AA64MMFR0_EL1);
1173 	read_sysreg_case(SYS_ID_AA64MMFR1_EL1);
1174 	read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
1175 	read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
1176 	read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
1177 	read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
1178 
1179 	read_sysreg_case(SYS_CNTFRQ_EL0);
1180 	read_sysreg_case(SYS_CTR_EL0);
1181 	read_sysreg_case(SYS_DCZID_EL0);
1182 
1183 	default:
1184 		BUG();
1185 		return 0;
1186 	}
1187 }
1188 
1189 #include <linux/irqchip/arm-gic-v3.h>
1190 
1191 static bool
feature_matches(u64 reg,const struct arm64_cpu_capabilities * entry)1192 feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
1193 {
1194 	int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign);
1195 
1196 	return val >= entry->min_field_value;
1197 }
1198 
1199 static bool
has_cpuid_feature(const struct arm64_cpu_capabilities * entry,int scope)1200 has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope)
1201 {
1202 	u64 val;
1203 
1204 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
1205 	if (scope == SCOPE_SYSTEM)
1206 		val = read_sanitised_ftr_reg(entry->sys_reg);
1207 	else
1208 		val = __read_sysreg_by_encoding(entry->sys_reg);
1209 
1210 	return feature_matches(val, entry);
1211 }
1212 
has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities * entry,int scope)1213 static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
1214 {
1215 	bool has_sre;
1216 
1217 	if (!has_cpuid_feature(entry, scope))
1218 		return false;
1219 
1220 	has_sre = gic_enable_sre();
1221 	if (!has_sre)
1222 		pr_warn_once("%s present but disabled by higher exception level\n",
1223 			     entry->desc);
1224 
1225 	return has_sre;
1226 }
1227 
has_no_hw_prefetch(const struct arm64_cpu_capabilities * entry,int __unused)1228 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
1229 {
1230 	u32 midr = read_cpuid_id();
1231 
1232 	/* Cavium ThunderX pass 1.x and 2.x */
1233 	return midr_is_cpu_model_range(midr, MIDR_THUNDERX,
1234 		MIDR_CPU_VAR_REV(0, 0),
1235 		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
1236 }
1237 
has_no_fpsimd(const struct arm64_cpu_capabilities * entry,int __unused)1238 static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
1239 {
1240 	u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1241 
1242 	return cpuid_feature_extract_signed_field(pfr0,
1243 					ID_AA64PFR0_FP_SHIFT) < 0;
1244 }
1245 
has_cache_idc(const struct arm64_cpu_capabilities * entry,int scope)1246 static bool has_cache_idc(const struct arm64_cpu_capabilities *entry,
1247 			  int scope)
1248 {
1249 	u64 ctr;
1250 
1251 	if (scope == SCOPE_SYSTEM)
1252 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1253 	else
1254 		ctr = read_cpuid_effective_cachetype();
1255 
1256 	return ctr & BIT(CTR_IDC_SHIFT);
1257 }
1258 
cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities * __unused)1259 static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused)
1260 {
1261 	/*
1262 	 * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively
1263 	 * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses
1264 	 * to the CTR_EL0 on this CPU and emulate it with the real/safe
1265 	 * value.
1266 	 */
1267 	if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT)))
1268 		sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0);
1269 }
1270 
has_cache_dic(const struct arm64_cpu_capabilities * entry,int scope)1271 static bool has_cache_dic(const struct arm64_cpu_capabilities *entry,
1272 			  int scope)
1273 {
1274 	u64 ctr;
1275 
1276 	if (scope == SCOPE_SYSTEM)
1277 		ctr = arm64_ftr_reg_ctrel0.sys_val;
1278 	else
1279 		ctr = read_cpuid_cachetype();
1280 
1281 	return ctr & BIT(CTR_DIC_SHIFT);
1282 }
1283 
1284 static bool __maybe_unused
has_useable_cnp(const struct arm64_cpu_capabilities * entry,int scope)1285 has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope)
1286 {
1287 	/*
1288 	 * Kdump isn't guaranteed to power-off all secondary CPUs, CNP
1289 	 * may share TLB entries with a CPU stuck in the crashed
1290 	 * kernel.
1291 	 */
1292 	 if (is_kdump_kernel())
1293 		return false;
1294 
1295 	return has_cpuid_feature(entry, scope);
1296 }
1297 
1298 /*
1299  * This check is triggered during the early boot before the cpufeature
1300  * is initialised. Checking the status on the local CPU allows the boot
1301  * CPU to detect the need for non-global mappings and thus avoiding a
1302  * pagetable re-write after all the CPUs are booted. This check will be
1303  * anyway run on individual CPUs, allowing us to get the consistent
1304  * state once the SMP CPUs are up and thus make the switch to non-global
1305  * mappings if required.
1306  */
kaslr_requires_kpti(void)1307 bool kaslr_requires_kpti(void)
1308 {
1309 	if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
1310 		return false;
1311 
1312 	/*
1313 	 * E0PD does a similar job to KPTI so can be used instead
1314 	 * where available.
1315 	 */
1316 	if (IS_ENABLED(CONFIG_ARM64_E0PD)) {
1317 		u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
1318 		if (cpuid_feature_extract_unsigned_field(mmfr2,
1319 						ID_AA64MMFR2_E0PD_SHIFT))
1320 			return false;
1321 	}
1322 
1323 	/*
1324 	 * Systems affected by Cavium erratum 24756 are incompatible
1325 	 * with KPTI.
1326 	 */
1327 	if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) {
1328 		extern const struct midr_range cavium_erratum_27456_cpus[];
1329 
1330 		if (is_midr_in_range_list(read_cpuid_id(),
1331 					  cavium_erratum_27456_cpus))
1332 			return false;
1333 	}
1334 
1335 	return kaslr_offset() > 0;
1336 }
1337 
1338 static bool __meltdown_safe = true;
1339 static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
1340 
unmap_kernel_at_el0(const struct arm64_cpu_capabilities * entry,int scope)1341 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
1342 				int scope)
1343 {
1344 	/* List of CPUs that are not vulnerable and don't need KPTI */
1345 	static const struct midr_range kpti_safe_list[] = {
1346 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
1347 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
1348 		MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
1349 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
1350 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
1351 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1352 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
1353 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
1354 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
1355 		MIDR_ALL_VERSIONS(MIDR_HISI_TSV110),
1356 		MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL),
1357 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_GOLD),
1358 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
1359 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
1360 		MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
1361 		{ /* sentinel */ }
1362 	};
1363 	char const *str = "kpti command line option";
1364 	bool meltdown_safe;
1365 
1366 	meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
1367 
1368 	/* Defer to CPU feature registers */
1369 	if (has_cpuid_feature(entry, scope))
1370 		meltdown_safe = true;
1371 
1372 	if (!meltdown_safe)
1373 		__meltdown_safe = false;
1374 
1375 	/*
1376 	 * For reasons that aren't entirely clear, enabling KPTI on Cavium
1377 	 * ThunderX leads to apparent I-cache corruption of kernel text, which
1378 	 * ends as well as you might imagine. Don't even try.
1379 	 */
1380 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) {
1381 		str = "ARM64_WORKAROUND_CAVIUM_27456";
1382 		__kpti_forced = -1;
1383 	}
1384 
1385 	/* Useful for KASLR robustness */
1386 	if (kaslr_requires_kpti()) {
1387 		if (!__kpti_forced) {
1388 			str = "KASLR";
1389 			__kpti_forced = 1;
1390 		}
1391 	}
1392 
1393 	if (cpu_mitigations_off() && !__kpti_forced) {
1394 		str = "mitigations=off";
1395 		__kpti_forced = -1;
1396 	}
1397 
1398 	if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
1399 		pr_info_once("kernel page table isolation disabled by kernel configuration\n");
1400 		return false;
1401 	}
1402 
1403 	/* Forced? */
1404 	if (__kpti_forced) {
1405 		pr_info_once("kernel page table isolation forced %s by %s\n",
1406 			     __kpti_forced > 0 ? "ON" : "OFF", str);
1407 		return __kpti_forced > 0;
1408 	}
1409 
1410 	return !meltdown_safe;
1411 }
1412 
1413 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
1414 static void __nocfi
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1415 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1416 {
1417 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
1418 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
1419 	kpti_remap_fn *remap_fn;
1420 
1421 	int cpu = smp_processor_id();
1422 
1423 	if (__this_cpu_read(this_cpu_vector) == vectors) {
1424 		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
1425 
1426 		__this_cpu_write(this_cpu_vector, v);
1427 	}
1428 
1429 	/*
1430 	 * We don't need to rewrite the page-tables if either we've done
1431 	 * it already or we have KASLR enabled and therefore have not
1432 	 * created any global mappings at all.
1433 	 */
1434 	if (arm64_use_ng_mappings)
1435 		return;
1436 
1437 	remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings));
1438 
1439 	cpu_install_idmap();
1440 	remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir));
1441 	cpu_uninstall_idmap();
1442 
1443 	if (!cpu)
1444 		arm64_use_ng_mappings = true;
1445 
1446 	return;
1447 }
1448 #else
1449 static void
kpti_install_ng_mappings(const struct arm64_cpu_capabilities * __unused)1450 kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
1451 {
1452 }
1453 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
1454 
parse_kpti(char * str)1455 static int __init parse_kpti(char *str)
1456 {
1457 	bool enabled;
1458 	int ret = strtobool(str, &enabled);
1459 
1460 	if (ret)
1461 		return ret;
1462 
1463 	__kpti_forced = enabled ? 1 : -1;
1464 	return 0;
1465 }
1466 early_param("kpti", parse_kpti);
1467 
1468 #ifdef CONFIG_ARM64_HW_AFDBM
__cpu_enable_hw_dbm(void)1469 static inline void __cpu_enable_hw_dbm(void)
1470 {
1471 	u64 tcr = read_sysreg(tcr_el1) | TCR_HD;
1472 
1473 	write_sysreg(tcr, tcr_el1);
1474 	isb();
1475 	local_flush_tlb_all();
1476 }
1477 
cpu_has_broken_dbm(void)1478 static bool cpu_has_broken_dbm(void)
1479 {
1480 	/* List of CPUs which have broken DBM support. */
1481 	static const struct midr_range cpus[] = {
1482 #ifdef CONFIG_ARM64_ERRATUM_1024718
1483 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
1484 		/* Kryo4xx Silver (rdpe => r1p0) */
1485 		MIDR_REV(MIDR_QCOM_KRYO_4XX_SILVER, 0xd, 0xe),
1486 #endif
1487 		{},
1488 	};
1489 
1490 	return is_midr_in_range_list(read_cpuid_id(), cpus);
1491 }
1492 
cpu_can_use_dbm(const struct arm64_cpu_capabilities * cap)1493 static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap)
1494 {
1495 	return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) &&
1496 	       !cpu_has_broken_dbm();
1497 }
1498 
cpu_enable_hw_dbm(struct arm64_cpu_capabilities const * cap)1499 static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap)
1500 {
1501 	if (cpu_can_use_dbm(cap))
1502 		__cpu_enable_hw_dbm();
1503 }
1504 
has_hw_dbm(const struct arm64_cpu_capabilities * cap,int __unused)1505 static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap,
1506 		       int __unused)
1507 {
1508 	static bool detected = false;
1509 	/*
1510 	 * DBM is a non-conflicting feature. i.e, the kernel can safely
1511 	 * run a mix of CPUs with and without the feature. So, we
1512 	 * unconditionally enable the capability to allow any late CPU
1513 	 * to use the feature. We only enable the control bits on the
1514 	 * CPU, if it actually supports.
1515 	 *
1516 	 * We have to make sure we print the "feature" detection only
1517 	 * when at least one CPU actually uses it. So check if this CPU
1518 	 * can actually use it and print the message exactly once.
1519 	 *
1520 	 * This is safe as all CPUs (including secondary CPUs - due to the
1521 	 * LOCAL_CPU scope - and the hotplugged CPUs - via verification)
1522 	 * goes through the "matches" check exactly once. Also if a CPU
1523 	 * matches the criteria, it is guaranteed that the CPU will turn
1524 	 * the DBM on, as the capability is unconditionally enabled.
1525 	 */
1526 	if (!detected && cpu_can_use_dbm(cap)) {
1527 		detected = true;
1528 		pr_info("detected: Hardware dirty bit management\n");
1529 	}
1530 
1531 	return true;
1532 }
1533 
1534 #endif
1535 
1536 #ifdef CONFIG_ARM64_AMU_EXTN
1537 
1538 /*
1539  * The "amu_cpus" cpumask only signals that the CPU implementation for the
1540  * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide
1541  * information regarding all the events that it supports. When a CPU bit is
1542  * set in the cpumask, the user of this feature can only rely on the presence
1543  * of the 4 fixed counters for that CPU. But this does not guarantee that the
1544  * counters are enabled or access to these counters is enabled by code
1545  * executed at higher exception levels (firmware).
1546  */
1547 static struct cpumask amu_cpus __read_mostly;
1548 
cpu_has_amu_feat(int cpu)1549 bool cpu_has_amu_feat(int cpu)
1550 {
1551 	return cpumask_test_cpu(cpu, &amu_cpus);
1552 }
1553 
1554 /* Initialize the use of AMU counters for frequency invariance */
1555 extern void init_cpu_freq_invariance_counters(void);
1556 
cpu_amu_enable(struct arm64_cpu_capabilities const * cap)1557 static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap)
1558 {
1559 	if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) {
1560 		pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n",
1561 			smp_processor_id());
1562 		cpumask_set_cpu(smp_processor_id(), &amu_cpus);
1563 
1564 		/* 0 reference values signal broken/disabled counters */
1565 		if (!this_cpu_has_cap(ARM64_WORKAROUND_2457168))
1566 			init_cpu_freq_invariance_counters();
1567 	}
1568 }
1569 
has_amu(const struct arm64_cpu_capabilities * cap,int __unused)1570 static bool has_amu(const struct arm64_cpu_capabilities *cap,
1571 		    int __unused)
1572 {
1573 	/*
1574 	 * The AMU extension is a non-conflicting feature: the kernel can
1575 	 * safely run a mix of CPUs with and without support for the
1576 	 * activity monitors extension. Therefore, unconditionally enable
1577 	 * the capability to allow any late CPU to use the feature.
1578 	 *
1579 	 * With this feature unconditionally enabled, the cpu_enable
1580 	 * function will be called for all CPUs that match the criteria,
1581 	 * including secondary and hotplugged, marking this feature as
1582 	 * present on that respective CPU. The enable function will also
1583 	 * print a detection message.
1584 	 */
1585 
1586 	return true;
1587 }
1588 #endif
1589 
1590 #ifdef CONFIG_ARM64_VHE
runs_at_el2(const struct arm64_cpu_capabilities * entry,int __unused)1591 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)
1592 {
1593 	return is_kernel_in_hyp_mode();
1594 }
1595 
cpu_copy_el2regs(const struct arm64_cpu_capabilities * __unused)1596 static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
1597 {
1598 	/*
1599 	 * Copy register values that aren't redirected by hardware.
1600 	 *
1601 	 * Before code patching, we only set tpidr_el1, all CPUs need to copy
1602 	 * this value to tpidr_el2 before we patch the code. Once we've done
1603 	 * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to
1604 	 * do anything here.
1605 	 */
1606 	if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN))
1607 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
1608 }
1609 #endif
1610 
cpu_has_fwb(const struct arm64_cpu_capabilities * __unused)1611 static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused)
1612 {
1613 	u64 val = read_sysreg_s(SYS_CLIDR_EL1);
1614 
1615 	/* Check that CLIDR_EL1.LOU{U,IS} are both 0 */
1616 	WARN_ON(val & (7 << 27 | 7 << 21));
1617 }
1618 
1619 #ifdef CONFIG_ARM64_PAN
cpu_enable_pan(const struct arm64_cpu_capabilities * __unused)1620 static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
1621 {
1622 	/*
1623 	 * We modify PSTATE. This won't work from irq context as the PSTATE
1624 	 * is discarded once we return from the exception.
1625 	 */
1626 	WARN_ON_ONCE(in_interrupt());
1627 
1628 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
1629 	asm(SET_PSTATE_PAN(1));
1630 }
1631 #endif /* CONFIG_ARM64_PAN */
1632 
1633 #ifdef CONFIG_ARM64_RAS_EXTN
cpu_clear_disr(const struct arm64_cpu_capabilities * __unused)1634 static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused)
1635 {
1636 	/* Firmware may have left a deferred SError in this register. */
1637 	write_sysreg_s(0, SYS_DISR_EL1);
1638 }
1639 #endif /* CONFIG_ARM64_RAS_EXTN */
1640 
1641 #ifdef CONFIG_ARM64_PTR_AUTH
has_address_auth_cpucap(const struct arm64_cpu_capabilities * entry,int scope)1642 static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope)
1643 {
1644 	int boot_val, sec_val;
1645 
1646 	/* We don't expect to be called with SCOPE_SYSTEM */
1647 	WARN_ON(scope == SCOPE_SYSTEM);
1648 	/*
1649 	 * The ptr-auth feature levels are not intercompatible with lower
1650 	 * levels. Hence we must match ptr-auth feature level of the secondary
1651 	 * CPUs with that of the boot CPU. The level of boot cpu is fetched
1652 	 * from the sanitised register whereas direct register read is done for
1653 	 * the secondary CPUs.
1654 	 * The sanitised feature state is guaranteed to match that of the
1655 	 * boot CPU as a mismatched secondary CPU is parked before it gets
1656 	 * a chance to update the state, with the capability.
1657 	 */
1658 	boot_val = cpuid_feature_extract_field(read_sanitised_ftr_reg(entry->sys_reg),
1659 					       entry->field_pos, entry->sign);
1660 	if (scope & SCOPE_BOOT_CPU)
1661 		return boot_val >= entry->min_field_value;
1662 	/* Now check for the secondary CPUs with SCOPE_LOCAL_CPU scope */
1663 	sec_val = cpuid_feature_extract_field(__read_sysreg_by_encoding(entry->sys_reg),
1664 					      entry->field_pos, entry->sign);
1665 	return sec_val == boot_val;
1666 }
1667 
has_address_auth_metacap(const struct arm64_cpu_capabilities * entry,int scope)1668 static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry,
1669 				     int scope)
1670 {
1671 	return has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_ARCH], scope) ||
1672 	       has_address_auth_cpucap(cpu_hwcaps_ptrs[ARM64_HAS_ADDRESS_AUTH_IMP_DEF], scope);
1673 }
1674 
has_generic_auth(const struct arm64_cpu_capabilities * entry,int __unused)1675 static bool has_generic_auth(const struct arm64_cpu_capabilities *entry,
1676 			     int __unused)
1677 {
1678 	return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) ||
1679 	       __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF);
1680 }
1681 #endif /* CONFIG_ARM64_PTR_AUTH */
1682 
1683 #ifdef CONFIG_ARM64_E0PD
cpu_enable_e0pd(struct arm64_cpu_capabilities const * cap)1684 static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
1685 {
1686 	if (this_cpu_has_cap(ARM64_HAS_E0PD))
1687 		sysreg_clear_set(tcr_el1, 0, TCR_E0PD1);
1688 }
1689 #endif /* CONFIG_ARM64_E0PD */
1690 
1691 #ifdef CONFIG_ARM64_PSEUDO_NMI
1692 static bool enable_pseudo_nmi;
1693 
early_enable_pseudo_nmi(char * p)1694 static int __init early_enable_pseudo_nmi(char *p)
1695 {
1696 	return strtobool(p, &enable_pseudo_nmi);
1697 }
1698 early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
1699 
can_use_gic_priorities(const struct arm64_cpu_capabilities * entry,int scope)1700 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
1701 				   int scope)
1702 {
1703 	return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope);
1704 }
1705 #endif
1706 
1707 #ifdef CONFIG_ARM64_BTI
bti_enable(const struct arm64_cpu_capabilities * __unused)1708 static void bti_enable(const struct arm64_cpu_capabilities *__unused)
1709 {
1710 	/*
1711 	 * Use of X16/X17 for tail-calls and trampolines that jump to
1712 	 * function entry points using BR is a requirement for
1713 	 * marking binaries with GNU_PROPERTY_AARCH64_FEATURE_1_BTI.
1714 	 * So, be strict and forbid other BRs using other registers to
1715 	 * jump onto a PACIxSP instruction:
1716 	 */
1717 	sysreg_clear_set(sctlr_el1, 0, SCTLR_EL1_BT0 | SCTLR_EL1_BT1);
1718 	isb();
1719 }
1720 #endif /* CONFIG_ARM64_BTI */
1721 
1722 #ifdef CONFIG_ARM64_MTE
cpu_enable_mte(struct arm64_cpu_capabilities const * cap)1723 static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
1724 {
1725 	/*
1726 	 * Clear the tags in the zero page. This needs to be done via the
1727 	 * linear map which has the Tagged attribute.
1728 	 */
1729 	if (!test_and_set_bit(PG_mte_tagged, &ZERO_PAGE(0)->flags))
1730 		mte_clear_page_tags(lm_alias(empty_zero_page));
1731 }
1732 #endif /* CONFIG_ARM64_MTE */
1733 
elf_hwcap_fixup(void)1734 static void elf_hwcap_fixup(void)
1735 {
1736 #ifdef CONFIG_ARM64_ERRATUM_1742098
1737 	if (cpus_have_const_cap(ARM64_WORKAROUND_1742098))
1738 		compat_elf_hwcap2 &= ~COMPAT_HWCAP2_AES;
1739 #endif /* ARM64_ERRATUM_1742098 */
1740 }
1741 
1742 /* Internal helper functions to match cpu capability type */
1743 static bool
cpucap_late_cpu_optional(const struct arm64_cpu_capabilities * cap)1744 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
1745 {
1746 	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
1747 }
1748 
1749 static bool
cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities * cap)1750 cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
1751 {
1752 	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
1753 }
1754 
1755 static bool
cpucap_panic_on_conflict(const struct arm64_cpu_capabilities * cap)1756 cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap)
1757 {
1758 	return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT);
1759 }
1760 
1761 static const struct arm64_cpu_capabilities arm64_features[] = {
1762 	{
1763 		.desc = "GIC system register CPU interface",
1764 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
1765 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1766 		.matches = has_useable_gicv3_cpuif,
1767 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1768 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
1769 		.sign = FTR_UNSIGNED,
1770 		.min_field_value = 1,
1771 	},
1772 #ifdef CONFIG_ARM64_PAN
1773 	{
1774 		.desc = "Privileged Access Never",
1775 		.capability = ARM64_HAS_PAN,
1776 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1777 		.matches = has_cpuid_feature,
1778 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
1779 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
1780 		.sign = FTR_UNSIGNED,
1781 		.min_field_value = 1,
1782 		.cpu_enable = cpu_enable_pan,
1783 	},
1784 #endif /* CONFIG_ARM64_PAN */
1785 #ifdef CONFIG_ARM64_LSE_ATOMICS
1786 	{
1787 		.desc = "LSE atomic instructions",
1788 		.capability = ARM64_HAS_LSE_ATOMICS,
1789 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1790 		.matches = has_cpuid_feature,
1791 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1792 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
1793 		.sign = FTR_UNSIGNED,
1794 		.min_field_value = 2,
1795 	},
1796 #endif /* CONFIG_ARM64_LSE_ATOMICS */
1797 	{
1798 		.desc = "Software prefetching using PRFM",
1799 		.capability = ARM64_HAS_NO_HW_PREFETCH,
1800 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1801 		.matches = has_no_hw_prefetch,
1802 	},
1803 #ifdef CONFIG_ARM64_UAO
1804 	{
1805 		.desc = "User Access Override",
1806 		.capability = ARM64_HAS_UAO,
1807 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1808 		.matches = has_cpuid_feature,
1809 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1810 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
1811 		.min_field_value = 1,
1812 		/*
1813 		 * We rely on stop_machine() calling uao_thread_switch() to set
1814 		 * UAO immediately after patching.
1815 		 */
1816 	},
1817 #endif /* CONFIG_ARM64_UAO */
1818 #ifdef CONFIG_ARM64_PAN
1819 	{
1820 		.capability = ARM64_ALT_PAN_NOT_UAO,
1821 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1822 		.matches = cpufeature_pan_not_uao,
1823 	},
1824 #endif /* CONFIG_ARM64_PAN */
1825 #ifdef CONFIG_ARM64_VHE
1826 	{
1827 		.desc = "Virtualization Host Extensions",
1828 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
1829 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
1830 		.matches = runs_at_el2,
1831 		.cpu_enable = cpu_copy_el2regs,
1832 	},
1833 #endif	/* CONFIG_ARM64_VHE */
1834 	{
1835 		.desc = "32-bit EL0 Support",
1836 		.capability = ARM64_HAS_32BIT_EL0,
1837 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1838 		.matches = has_cpuid_feature,
1839 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1840 		.sign = FTR_UNSIGNED,
1841 		.field_pos = ID_AA64PFR0_EL0_SHIFT,
1842 		.min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
1843 	},
1844 #ifdef CONFIG_KVM
1845 	{
1846 		.desc = "32-bit EL1 Support",
1847 		.capability = ARM64_HAS_32BIT_EL1,
1848 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1849 		.matches = has_cpuid_feature,
1850 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1851 		.sign = FTR_UNSIGNED,
1852 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
1853 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
1854 	},
1855 #endif
1856 	{
1857 		.desc = "Kernel page table isolation (KPTI)",
1858 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
1859 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1860 		/*
1861 		 * The ID feature fields below are used to indicate that
1862 		 * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for
1863 		 * more details.
1864 		 */
1865 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1866 		.field_pos = ID_AA64PFR0_CSV3_SHIFT,
1867 		.min_field_value = 1,
1868 		.matches = unmap_kernel_at_el0,
1869 		.cpu_enable = kpti_install_ng_mappings,
1870 	},
1871 	{
1872 		/* FP/SIMD is not implemented */
1873 		.capability = ARM64_HAS_NO_FPSIMD,
1874 		.type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE,
1875 		.min_field_value = 0,
1876 		.matches = has_no_fpsimd,
1877 	},
1878 #ifdef CONFIG_ARM64_PMEM
1879 	{
1880 		.desc = "Data cache clean to Point of Persistence",
1881 		.capability = ARM64_HAS_DCPOP,
1882 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1883 		.matches = has_cpuid_feature,
1884 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1885 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1886 		.min_field_value = 1,
1887 	},
1888 	{
1889 		.desc = "Data cache clean to Point of Deep Persistence",
1890 		.capability = ARM64_HAS_DCPODP,
1891 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1892 		.matches = has_cpuid_feature,
1893 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
1894 		.sign = FTR_UNSIGNED,
1895 		.field_pos = ID_AA64ISAR1_DPB_SHIFT,
1896 		.min_field_value = 2,
1897 	},
1898 #endif
1899 #ifdef CONFIG_ARM64_SVE
1900 	{
1901 		.desc = "Scalable Vector Extension",
1902 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1903 		.capability = ARM64_SVE,
1904 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1905 		.sign = FTR_UNSIGNED,
1906 		.field_pos = ID_AA64PFR0_SVE_SHIFT,
1907 		.min_field_value = ID_AA64PFR0_SVE,
1908 		.matches = has_cpuid_feature,
1909 		.cpu_enable = sve_kernel_enable,
1910 	},
1911 #endif /* CONFIG_ARM64_SVE */
1912 #ifdef CONFIG_ARM64_RAS_EXTN
1913 	{
1914 		.desc = "RAS Extension Support",
1915 		.capability = ARM64_HAS_RAS_EXTN,
1916 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1917 		.matches = has_cpuid_feature,
1918 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1919 		.sign = FTR_UNSIGNED,
1920 		.field_pos = ID_AA64PFR0_RAS_SHIFT,
1921 		.min_field_value = ID_AA64PFR0_RAS_V1,
1922 		.cpu_enable = cpu_clear_disr,
1923 	},
1924 #endif /* CONFIG_ARM64_RAS_EXTN */
1925 #ifdef CONFIG_ARM64_AMU_EXTN
1926 	{
1927 		/*
1928 		 * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y.
1929 		 * Therefore, don't provide .desc as we don't want the detection
1930 		 * message to be shown until at least one CPU is detected to
1931 		 * support the feature.
1932 		 */
1933 		.capability = ARM64_HAS_AMU_EXTN,
1934 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1935 		.matches = has_amu,
1936 		.sys_reg = SYS_ID_AA64PFR0_EL1,
1937 		.sign = FTR_UNSIGNED,
1938 		.field_pos = ID_AA64PFR0_AMU_SHIFT,
1939 		.min_field_value = ID_AA64PFR0_AMU,
1940 		.cpu_enable = cpu_amu_enable,
1941 	},
1942 #endif /* CONFIG_ARM64_AMU_EXTN */
1943 	{
1944 		.desc = "Data cache clean to the PoU not required for I/D coherence",
1945 		.capability = ARM64_HAS_CACHE_IDC,
1946 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1947 		.matches = has_cache_idc,
1948 		.cpu_enable = cpu_emulate_effective_ctr,
1949 	},
1950 	{
1951 		.desc = "Instruction cache invalidation not required for I/D coherence",
1952 		.capability = ARM64_HAS_CACHE_DIC,
1953 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1954 		.matches = has_cache_dic,
1955 	},
1956 	{
1957 		.desc = "Stage-2 Force Write-Back",
1958 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1959 		.capability = ARM64_HAS_STAGE2_FWB,
1960 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1961 		.sign = FTR_UNSIGNED,
1962 		.field_pos = ID_AA64MMFR2_FWB_SHIFT,
1963 		.min_field_value = 1,
1964 		.matches = has_cpuid_feature,
1965 		.cpu_enable = cpu_has_fwb,
1966 	},
1967 	{
1968 		.desc = "ARMv8.4 Translation Table Level",
1969 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1970 		.capability = ARM64_HAS_ARMv8_4_TTL,
1971 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
1972 		.sign = FTR_UNSIGNED,
1973 		.field_pos = ID_AA64MMFR2_TTL_SHIFT,
1974 		.min_field_value = 1,
1975 		.matches = has_cpuid_feature,
1976 	},
1977 	{
1978 		.desc = "TLB range maintenance instructions",
1979 		.capability = ARM64_HAS_TLB_RANGE,
1980 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
1981 		.matches = has_cpuid_feature,
1982 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
1983 		.field_pos = ID_AA64ISAR0_TLB_SHIFT,
1984 		.sign = FTR_UNSIGNED,
1985 		.min_field_value = ID_AA64ISAR0_TLB_RANGE,
1986 	},
1987 #ifdef CONFIG_ARM64_HW_AFDBM
1988 	{
1989 		/*
1990 		 * Since we turn this on always, we don't want the user to
1991 		 * think that the feature is available when it may not be.
1992 		 * So hide the description.
1993 		 *
1994 		 * .desc = "Hardware pagetable Dirty Bit Management",
1995 		 *
1996 		 */
1997 		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
1998 		.capability = ARM64_HW_DBM,
1999 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
2000 		.sign = FTR_UNSIGNED,
2001 		.field_pos = ID_AA64MMFR1_HADBS_SHIFT,
2002 		.min_field_value = 2,
2003 		.matches = has_hw_dbm,
2004 		.cpu_enable = cpu_enable_hw_dbm,
2005 	},
2006 #endif
2007 	{
2008 		.desc = "CRC32 instructions",
2009 		.capability = ARM64_HAS_CRC32,
2010 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2011 		.matches = has_cpuid_feature,
2012 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2013 		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,
2014 		.min_field_value = 1,
2015 	},
2016 	{
2017 		.desc = "Speculative Store Bypassing Safe (SSBS)",
2018 		.capability = ARM64_SSBS,
2019 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2020 		.matches = has_cpuid_feature,
2021 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2022 		.field_pos = ID_AA64PFR1_SSBS_SHIFT,
2023 		.sign = FTR_UNSIGNED,
2024 		.min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY,
2025 	},
2026 #ifdef CONFIG_ARM64_CNP
2027 	{
2028 		.desc = "Common not Private translations",
2029 		.capability = ARM64_HAS_CNP,
2030 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2031 		.matches = has_useable_cnp,
2032 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2033 		.sign = FTR_UNSIGNED,
2034 		.field_pos = ID_AA64MMFR2_CNP_SHIFT,
2035 		.min_field_value = 1,
2036 		.cpu_enable = cpu_enable_cnp,
2037 	},
2038 #endif
2039 	{
2040 		.desc = "Speculation barrier (SB)",
2041 		.capability = ARM64_HAS_SB,
2042 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2043 		.matches = has_cpuid_feature,
2044 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2045 		.field_pos = ID_AA64ISAR1_SB_SHIFT,
2046 		.sign = FTR_UNSIGNED,
2047 		.min_field_value = 1,
2048 	},
2049 #ifdef CONFIG_ARM64_PTR_AUTH
2050 	{
2051 		.desc = "Address authentication (architected algorithm)",
2052 		.capability = ARM64_HAS_ADDRESS_AUTH_ARCH,
2053 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2054 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2055 		.sign = FTR_UNSIGNED,
2056 		.field_pos = ID_AA64ISAR1_APA_SHIFT,
2057 		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
2058 		.matches = has_address_auth_cpucap,
2059 	},
2060 	{
2061 		.desc = "Address authentication (IMP DEF algorithm)",
2062 		.capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF,
2063 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2064 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2065 		.sign = FTR_UNSIGNED,
2066 		.field_pos = ID_AA64ISAR1_API_SHIFT,
2067 		.min_field_value = ID_AA64ISAR1_API_IMP_DEF,
2068 		.matches = has_address_auth_cpucap,
2069 	},
2070 	{
2071 		.capability = ARM64_HAS_ADDRESS_AUTH,
2072 		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
2073 		.matches = has_address_auth_metacap,
2074 	},
2075 	{
2076 		.desc = "Generic authentication (architected algorithm)",
2077 		.capability = ARM64_HAS_GENERIC_AUTH_ARCH,
2078 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2079 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2080 		.sign = FTR_UNSIGNED,
2081 		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
2082 		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
2083 		.matches = has_cpuid_feature,
2084 	},
2085 	{
2086 		.desc = "Generic authentication (IMP DEF algorithm)",
2087 		.capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF,
2088 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2089 		.sys_reg = SYS_ID_AA64ISAR1_EL1,
2090 		.sign = FTR_UNSIGNED,
2091 		.field_pos = ID_AA64ISAR1_GPI_SHIFT,
2092 		.min_field_value = ID_AA64ISAR1_GPI_IMP_DEF,
2093 		.matches = has_cpuid_feature,
2094 	},
2095 	{
2096 		.capability = ARM64_HAS_GENERIC_AUTH,
2097 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2098 		.matches = has_generic_auth,
2099 	},
2100 #endif /* CONFIG_ARM64_PTR_AUTH */
2101 #ifdef CONFIG_ARM64_PSEUDO_NMI
2102 	{
2103 		/*
2104 		 * Depends on having GICv3
2105 		 */
2106 		.desc = "IRQ priority masking",
2107 		.capability = ARM64_HAS_IRQ_PRIO_MASKING,
2108 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2109 		.matches = can_use_gic_priorities,
2110 		.sys_reg = SYS_ID_AA64PFR0_EL1,
2111 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
2112 		.sign = FTR_UNSIGNED,
2113 		.min_field_value = 1,
2114 	},
2115 #endif
2116 #ifdef CONFIG_ARM64_E0PD
2117 	{
2118 		.desc = "E0PD",
2119 		.capability = ARM64_HAS_E0PD,
2120 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2121 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
2122 		.sign = FTR_UNSIGNED,
2123 		.field_pos = ID_AA64MMFR2_E0PD_SHIFT,
2124 		.matches = has_cpuid_feature,
2125 		.min_field_value = 1,
2126 		.cpu_enable = cpu_enable_e0pd,
2127 	},
2128 #endif
2129 #ifdef CONFIG_ARCH_RANDOM
2130 	{
2131 		.desc = "Random Number Generator",
2132 		.capability = ARM64_HAS_RNG,
2133 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2134 		.matches = has_cpuid_feature,
2135 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
2136 		.field_pos = ID_AA64ISAR0_RNDR_SHIFT,
2137 		.sign = FTR_UNSIGNED,
2138 		.min_field_value = 1,
2139 	},
2140 #endif
2141 #ifdef CONFIG_ARM64_BTI
2142 	{
2143 		.desc = "Branch Target Identification",
2144 		.capability = ARM64_BTI,
2145 #ifdef CONFIG_ARM64_BTI_KERNEL
2146 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2147 #else
2148 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
2149 #endif
2150 		.matches = has_cpuid_feature,
2151 		.cpu_enable = bti_enable,
2152 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2153 		.field_pos = ID_AA64PFR1_BT_SHIFT,
2154 		.min_field_value = ID_AA64PFR1_BT_BTI,
2155 		.sign = FTR_UNSIGNED,
2156 	},
2157 #endif
2158 #ifdef CONFIG_ARM64_MTE
2159 	{
2160 		.desc = "Memory Tagging Extension",
2161 		.capability = ARM64_MTE,
2162 		.type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
2163 		.matches = has_cpuid_feature,
2164 		.sys_reg = SYS_ID_AA64PFR1_EL1,
2165 		.field_pos = ID_AA64PFR1_MTE_SHIFT,
2166 		.min_field_value = ID_AA64PFR1_MTE,
2167 		.sign = FTR_UNSIGNED,
2168 		.cpu_enable = cpu_enable_mte,
2169 	},
2170 #endif /* CONFIG_ARM64_MTE */
2171 	{},
2172 };
2173 
2174 #define HWCAP_CPUID_MATCH(reg, field, s, min_value)				\
2175 		.matches = has_cpuid_feature,					\
2176 		.sys_reg = reg,							\
2177 		.field_pos = field,						\
2178 		.sign = s,							\
2179 		.min_field_value = min_value,
2180 
2181 #define __HWCAP_CAP(name, cap_type, cap)					\
2182 		.desc = name,							\
2183 		.type = ARM64_CPUCAP_SYSTEM_FEATURE,				\
2184 		.hwcap_type = cap_type,						\
2185 		.hwcap = cap,							\
2186 
2187 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)			\
2188 	{									\
2189 		__HWCAP_CAP(#cap, cap_type, cap)				\
2190 		HWCAP_CPUID_MATCH(reg, field, s, min_value)			\
2191 	}
2192 
2193 #define HWCAP_MULTI_CAP(list, cap_type, cap)					\
2194 	{									\
2195 		__HWCAP_CAP(#cap, cap_type, cap)				\
2196 		.matches = cpucap_multi_entry_cap_matches,			\
2197 		.match_list = list,						\
2198 	}
2199 
2200 #define HWCAP_CAP_MATCH(match, cap_type, cap)					\
2201 	{									\
2202 		__HWCAP_CAP(#cap, cap_type, cap)				\
2203 		.matches = match,						\
2204 	}
2205 
2206 #ifdef CONFIG_ARM64_PTR_AUTH
2207 static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = {
2208 	{
2209 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT,
2210 				  FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED)
2211 	},
2212 	{
2213 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT,
2214 				  FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF)
2215 	},
2216 	{},
2217 };
2218 
2219 static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = {
2220 	{
2221 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT,
2222 				  FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED)
2223 	},
2224 	{
2225 		HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT,
2226 				  FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF)
2227 	},
2228 	{},
2229 };
2230 #endif
2231 
2232 static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
2233 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL),
2234 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES),
2235 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1),
2236 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2),
2237 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512),
2238 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32),
2239 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
2240 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
2241 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3),
2242 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3),
2243 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4),
2244 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP),
2245 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM),
2246 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM),
2247 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2),
2248 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG),
2249 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP),
2250 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP),
2251 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
2252 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
2253 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT),
2254 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
2255 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
2256 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
2257 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA),
2258 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
2259 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC),
2260 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
2261 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
2262 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
2263 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
2264 	HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
2265 	HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
2266 #ifdef CONFIG_ARM64_SVE
2267 	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE),
2268 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2),
2269 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES),
2270 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL),
2271 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM),
2272 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16),
2273 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3),
2274 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4),
2275 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
2276 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
2277 	HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
2278 #endif
2279 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS),
2280 #ifdef CONFIG_ARM64_BTI
2281 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_BT_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_BT_BTI, CAP_HWCAP, KERNEL_HWCAP_BTI),
2282 #endif
2283 #ifdef CONFIG_ARM64_PTR_AUTH
2284 	HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA),
2285 	HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG),
2286 #endif
2287 #ifdef CONFIG_ARM64_MTE
2288 	HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
2289 #endif /* CONFIG_ARM64_MTE */
2290 	HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
2291 	HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
2292 	HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
2293 	{},
2294 };
2295 
2296 #ifdef CONFIG_COMPAT
compat_has_neon(const struct arm64_cpu_capabilities * cap,int scope)2297 static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
2298 {
2299 	/*
2300 	 * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available,
2301 	 * in line with that of arm32 as in vfp_init(). We make sure that the
2302 	 * check is future proof, by making sure value is non-zero.
2303 	 */
2304 	u32 mvfr1;
2305 
2306 	WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible());
2307 	if (scope == SCOPE_SYSTEM)
2308 		mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1);
2309 	else
2310 		mvfr1 = read_sysreg_s(SYS_MVFR1_EL1);
2311 
2312 	return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) &&
2313 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) &&
2314 		cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT);
2315 }
2316 #endif
2317 
2318 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
2319 #ifdef CONFIG_COMPAT
2320 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
2321 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
2322 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
2323 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
2324 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
2325 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
2326 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
2327 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
2328 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2),
2329 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32),
2330 #endif
2331 	{},
2332 };
2333 
cap_set_elf_hwcap(const struct arm64_cpu_capabilities * cap)2334 static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2335 {
2336 	switch (cap->hwcap_type) {
2337 	case CAP_HWCAP:
2338 		cpu_set_feature(cap->hwcap);
2339 		break;
2340 #ifdef CONFIG_COMPAT
2341 	case CAP_COMPAT_HWCAP:
2342 		compat_elf_hwcap |= (u32)cap->hwcap;
2343 		break;
2344 	case CAP_COMPAT_HWCAP2:
2345 		compat_elf_hwcap2 |= (u32)cap->hwcap;
2346 		break;
2347 #endif
2348 	default:
2349 		WARN_ON(1);
2350 		break;
2351 	}
2352 }
2353 
2354 /* Check if we have a particular HWCAP enabled */
cpus_have_elf_hwcap(const struct arm64_cpu_capabilities * cap)2355 static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
2356 {
2357 	bool rc;
2358 
2359 	switch (cap->hwcap_type) {
2360 	case CAP_HWCAP:
2361 		rc = cpu_have_feature(cap->hwcap);
2362 		break;
2363 #ifdef CONFIG_COMPAT
2364 	case CAP_COMPAT_HWCAP:
2365 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
2366 		break;
2367 	case CAP_COMPAT_HWCAP2:
2368 		rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0;
2369 		break;
2370 #endif
2371 	default:
2372 		WARN_ON(1);
2373 		rc = false;
2374 	}
2375 
2376 	return rc;
2377 }
2378 
setup_elf_hwcaps(const struct arm64_cpu_capabilities * hwcaps)2379 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
2380 {
2381 	/* We support emulation of accesses to CPU ID feature registers */
2382 	cpu_set_named_feature(CPUID);
2383 	for (; hwcaps->matches; hwcaps++)
2384 		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
2385 			cap_set_elf_hwcap(hwcaps);
2386 }
2387 
update_cpu_capabilities(u16 scope_mask)2388 static void update_cpu_capabilities(u16 scope_mask)
2389 {
2390 	int i;
2391 	const struct arm64_cpu_capabilities *caps;
2392 
2393 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2394 	for (i = 0; i < ARM64_NCAPS; i++) {
2395 		caps = cpu_hwcaps_ptrs[i];
2396 		if (!caps || !(caps->type & scope_mask) ||
2397 		    cpus_have_cap(caps->capability) ||
2398 		    !caps->matches(caps, cpucap_default_scope(caps)))
2399 			continue;
2400 
2401 		if (caps->desc)
2402 			pr_info("detected: %s\n", caps->desc);
2403 		cpus_set_cap(caps->capability);
2404 
2405 		if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU))
2406 			set_bit(caps->capability, boot_capabilities);
2407 	}
2408 }
2409 
2410 /*
2411  * Enable all the available capabilities on this CPU. The capabilities
2412  * with BOOT_CPU scope are handled separately and hence skipped here.
2413  */
cpu_enable_non_boot_scope_capabilities(void * __unused)2414 static int cpu_enable_non_boot_scope_capabilities(void *__unused)
2415 {
2416 	int i;
2417 	u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU;
2418 
2419 	for_each_available_cap(i) {
2420 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i];
2421 
2422 		if (WARN_ON(!cap))
2423 			continue;
2424 
2425 		if (!(cap->type & non_boot_scope))
2426 			continue;
2427 
2428 		if (cap->cpu_enable)
2429 			cap->cpu_enable(cap);
2430 	}
2431 	return 0;
2432 }
2433 
2434 /*
2435  * Run through the enabled capabilities and enable() it on all active
2436  * CPUs
2437  */
enable_cpu_capabilities(u16 scope_mask)2438 static void __init enable_cpu_capabilities(u16 scope_mask)
2439 {
2440 	int i;
2441 	const struct arm64_cpu_capabilities *caps;
2442 	bool boot_scope;
2443 
2444 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2445 	boot_scope = !!(scope_mask & SCOPE_BOOT_CPU);
2446 
2447 	for (i = 0; i < ARM64_NCAPS; i++) {
2448 		unsigned int num;
2449 
2450 		caps = cpu_hwcaps_ptrs[i];
2451 		if (!caps || !(caps->type & scope_mask))
2452 			continue;
2453 		num = caps->capability;
2454 		if (!cpus_have_cap(num))
2455 			continue;
2456 
2457 		/* Ensure cpus_have_const_cap(num) works */
2458 		static_branch_enable(&cpu_hwcap_keys[num]);
2459 
2460 		if (boot_scope && caps->cpu_enable)
2461 			/*
2462 			 * Capabilities with SCOPE_BOOT_CPU scope are finalised
2463 			 * before any secondary CPU boots. Thus, each secondary
2464 			 * will enable the capability as appropriate via
2465 			 * check_local_cpu_capabilities(). The only exception is
2466 			 * the boot CPU, for which the capability must be
2467 			 * enabled here. This approach avoids costly
2468 			 * stop_machine() calls for this case.
2469 			 */
2470 			caps->cpu_enable(caps);
2471 	}
2472 
2473 	/*
2474 	 * For all non-boot scope capabilities, use stop_machine()
2475 	 * as it schedules the work allowing us to modify PSTATE,
2476 	 * instead of on_each_cpu() which uses an IPI, giving us a
2477 	 * PSTATE that disappears when we return.
2478 	 */
2479 	if (!boot_scope)
2480 		stop_machine(cpu_enable_non_boot_scope_capabilities,
2481 			     NULL, cpu_online_mask);
2482 }
2483 
2484 /*
2485  * Run through the list of capabilities to check for conflicts.
2486  * If the system has already detected a capability, take necessary
2487  * action on this CPU.
2488  */
verify_local_cpu_caps(u16 scope_mask)2489 static void verify_local_cpu_caps(u16 scope_mask)
2490 {
2491 	int i;
2492 	bool cpu_has_cap, system_has_cap;
2493 	const struct arm64_cpu_capabilities *caps;
2494 
2495 	scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
2496 
2497 	for (i = 0; i < ARM64_NCAPS; i++) {
2498 		caps = cpu_hwcaps_ptrs[i];
2499 		if (!caps || !(caps->type & scope_mask))
2500 			continue;
2501 
2502 		cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
2503 		system_has_cap = cpus_have_cap(caps->capability);
2504 
2505 		if (system_has_cap) {
2506 			/*
2507 			 * Check if the new CPU misses an advertised feature,
2508 			 * which is not safe to miss.
2509 			 */
2510 			if (!cpu_has_cap && !cpucap_late_cpu_optional(caps))
2511 				break;
2512 			/*
2513 			 * We have to issue cpu_enable() irrespective of
2514 			 * whether the CPU has it or not, as it is enabeld
2515 			 * system wide. It is upto the call back to take
2516 			 * appropriate action on this CPU.
2517 			 */
2518 			if (caps->cpu_enable)
2519 				caps->cpu_enable(caps);
2520 		} else {
2521 			/*
2522 			 * Check if the CPU has this capability if it isn't
2523 			 * safe to have when the system doesn't.
2524 			 */
2525 			if (cpu_has_cap && !cpucap_late_cpu_permitted(caps))
2526 				break;
2527 		}
2528 	}
2529 
2530 	if (i < ARM64_NCAPS) {
2531 		pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
2532 			smp_processor_id(), caps->capability,
2533 			caps->desc, system_has_cap, cpu_has_cap);
2534 
2535 		if (cpucap_panic_on_conflict(caps))
2536 			cpu_panic_kernel();
2537 		else
2538 			cpu_die_early();
2539 	}
2540 }
2541 
2542 /*
2543  * Check for CPU features that are used in early boot
2544  * based on the Boot CPU value.
2545  */
check_early_cpu_features(void)2546 static void check_early_cpu_features(void)
2547 {
2548 	verify_cpu_asid_bits();
2549 
2550 	verify_local_cpu_caps(SCOPE_BOOT_CPU);
2551 }
2552 
2553 static void
verify_local_elf_hwcaps(const struct arm64_cpu_capabilities * caps)2554 verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
2555 {
2556 
2557 	for (; caps->matches; caps++)
2558 		if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) {
2559 			pr_crit("CPU%d: missing HWCAP: %s\n",
2560 					smp_processor_id(), caps->desc);
2561 			cpu_die_early();
2562 		}
2563 }
2564 
verify_sve_features(void)2565 static void verify_sve_features(void)
2566 {
2567 	u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1);
2568 	u64 zcr = read_zcr_features();
2569 
2570 	unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK;
2571 	unsigned int len = zcr & ZCR_ELx_LEN_MASK;
2572 
2573 	if (len < safe_len || sve_verify_vq_map()) {
2574 		pr_crit("CPU%d: SVE: vector length support mismatch\n",
2575 			smp_processor_id());
2576 		cpu_die_early();
2577 	}
2578 
2579 	/* Add checks on other ZCR bits here if necessary */
2580 }
2581 
verify_hyp_capabilities(void)2582 static void verify_hyp_capabilities(void)
2583 {
2584 	u64 safe_mmfr1, mmfr0, mmfr1;
2585 	int parange, ipa_max;
2586 	unsigned int safe_vmid_bits, vmid_bits;
2587 
2588 	if (!IS_ENABLED(CONFIG_KVM))
2589 		return;
2590 
2591 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2592 	mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
2593 	mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
2594 
2595 	/* Verify VMID bits */
2596 	safe_vmid_bits = get_vmid_bits(safe_mmfr1);
2597 	vmid_bits = get_vmid_bits(mmfr1);
2598 	if (vmid_bits < safe_vmid_bits) {
2599 		pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id());
2600 		cpu_die_early();
2601 	}
2602 
2603 	/* Verify IPA range */
2604 	parange = cpuid_feature_extract_unsigned_field(mmfr0,
2605 				ID_AA64MMFR0_PARANGE_SHIFT);
2606 	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
2607 	if (ipa_max < get_kvm_ipa_limit()) {
2608 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
2609 		cpu_die_early();
2610 	}
2611 }
2612 
2613 /*
2614  * Run through the enabled system capabilities and enable() it on this CPU.
2615  * The capabilities were decided based on the available CPUs at the boot time.
2616  * Any new CPU should match the system wide status of the capability. If the
2617  * new CPU doesn't have a capability which the system now has enabled, we
2618  * cannot do anything to fix it up and could cause unexpected failures. So
2619  * we park the CPU.
2620  */
verify_local_cpu_capabilities(void)2621 static void verify_local_cpu_capabilities(void)
2622 {
2623 	/*
2624 	 * The capabilities with SCOPE_BOOT_CPU are checked from
2625 	 * check_early_cpu_features(), as they need to be verified
2626 	 * on all secondary CPUs.
2627 	 */
2628 	verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2629 
2630 	verify_local_elf_hwcaps(arm64_elf_hwcaps);
2631 
2632 	if (system_supports_32bit_el0())
2633 		verify_local_elf_hwcaps(compat_elf_hwcaps);
2634 
2635 	if (system_supports_sve())
2636 		verify_sve_features();
2637 
2638 	if (is_hyp_mode_available())
2639 		verify_hyp_capabilities();
2640 }
2641 
check_local_cpu_capabilities(void)2642 void check_local_cpu_capabilities(void)
2643 {
2644 	/*
2645 	 * All secondary CPUs should conform to the early CPU features
2646 	 * in use by the kernel based on boot CPU.
2647 	 */
2648 	check_early_cpu_features();
2649 
2650 	/*
2651 	 * If we haven't finalised the system capabilities, this CPU gets
2652 	 * a chance to update the errata work arounds and local features.
2653 	 * Otherwise, this CPU should verify that it has all the system
2654 	 * advertised capabilities.
2655 	 */
2656 	if (!system_capabilities_finalized())
2657 		update_cpu_capabilities(SCOPE_LOCAL_CPU);
2658 	else
2659 		verify_local_cpu_capabilities();
2660 }
2661 
setup_boot_cpu_capabilities(void)2662 static void __init setup_boot_cpu_capabilities(void)
2663 {
2664 	/* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */
2665 	update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU);
2666 	/* Enable the SCOPE_BOOT_CPU capabilities alone right away */
2667 	enable_cpu_capabilities(SCOPE_BOOT_CPU);
2668 }
2669 
this_cpu_has_cap(unsigned int n)2670 bool this_cpu_has_cap(unsigned int n)
2671 {
2672 	if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) {
2673 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2674 
2675 		if (cap)
2676 			return cap->matches(cap, SCOPE_LOCAL_CPU);
2677 	}
2678 
2679 	return false;
2680 }
2681 
2682 /*
2683  * This helper function is used in a narrow window when,
2684  * - The system wide safe registers are set with all the SMP CPUs and,
2685  * - The SYSTEM_FEATURE cpu_hwcaps may not have been set.
2686  * In all other cases cpus_have_{const_}cap() should be used.
2687  */
__system_matches_cap(unsigned int n)2688 static bool __system_matches_cap(unsigned int n)
2689 {
2690 	if (n < ARM64_NCAPS) {
2691 		const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n];
2692 
2693 		if (cap)
2694 			return cap->matches(cap, SCOPE_SYSTEM);
2695 	}
2696 	return false;
2697 }
2698 
cpu_set_feature(unsigned int num)2699 void cpu_set_feature(unsigned int num)
2700 {
2701 	WARN_ON(num >= MAX_CPU_FEATURES);
2702 	elf_hwcap |= BIT(num);
2703 }
2704 EXPORT_SYMBOL_GPL(cpu_set_feature);
2705 
cpu_have_feature(unsigned int num)2706 bool cpu_have_feature(unsigned int num)
2707 {
2708 	WARN_ON(num >= MAX_CPU_FEATURES);
2709 	return elf_hwcap & BIT(num);
2710 }
2711 EXPORT_SYMBOL_GPL(cpu_have_feature);
2712 
cpu_get_elf_hwcap(void)2713 unsigned long cpu_get_elf_hwcap(void)
2714 {
2715 	/*
2716 	 * We currently only populate the first 32 bits of AT_HWCAP. Please
2717 	 * note that for userspace compatibility we guarantee that bits 62
2718 	 * and 63 will always be returned as 0.
2719 	 */
2720 	return lower_32_bits(elf_hwcap);
2721 }
2722 
cpu_get_elf_hwcap2(void)2723 unsigned long cpu_get_elf_hwcap2(void)
2724 {
2725 	return upper_32_bits(elf_hwcap);
2726 }
2727 
setup_system_capabilities(void)2728 static void __init setup_system_capabilities(void)
2729 {
2730 	/*
2731 	 * We have finalised the system-wide safe feature
2732 	 * registers, finalise the capabilities that depend
2733 	 * on it. Also enable all the available capabilities,
2734 	 * that are not enabled already.
2735 	 */
2736 	update_cpu_capabilities(SCOPE_SYSTEM);
2737 	enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU);
2738 }
2739 
setup_cpu_features(void)2740 void __init setup_cpu_features(void)
2741 {
2742 	u32 cwg;
2743 
2744 	setup_system_capabilities();
2745 	setup_elf_hwcaps(arm64_elf_hwcaps);
2746 
2747 	if (system_supports_32bit_el0()) {
2748 		setup_elf_hwcaps(compat_elf_hwcaps);
2749 		elf_hwcap_fixup();
2750 	}
2751 
2752 	if (system_uses_ttbr0_pan())
2753 		pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
2754 
2755 	sve_setup();
2756 	minsigstksz_setup();
2757 
2758 	/* Advertise that we have computed the system capabilities */
2759 	finalize_system_capabilities();
2760 
2761 	/*
2762 	 * Check for sane CTR_EL0.CWG value.
2763 	 */
2764 	cwg = cache_type_cwg();
2765 	if (!cwg)
2766 		pr_warn("No Cache Writeback Granule information, assuming %d\n",
2767 			ARCH_DMA_MINALIGN);
2768 }
2769 
2770 static bool __maybe_unused
cpufeature_pan_not_uao(const struct arm64_cpu_capabilities * entry,int __unused)2771 cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
2772 {
2773 	return (__system_matches_cap(ARM64_HAS_PAN) && !__system_matches_cap(ARM64_HAS_UAO));
2774 }
2775 
cpu_enable_cnp(struct arm64_cpu_capabilities const * cap)2776 static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
2777 {
2778 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2779 }
2780 
2781 /*
2782  * We emulate only the following system register space.
2783  * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7]
2784  * See Table C5-6 System instruction encodings for System register accesses,
2785  * ARMv8 ARM(ARM DDI 0487A.f) for more details.
2786  */
is_emulated(u32 id)2787 static inline bool __attribute_const__ is_emulated(u32 id)
2788 {
2789 	return (sys_reg_Op0(id) == 0x3 &&
2790 		sys_reg_CRn(id) == 0x0 &&
2791 		sys_reg_Op1(id) == 0x0 &&
2792 		(sys_reg_CRm(id) == 0 ||
2793 		 ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7))));
2794 }
2795 
2796 /*
2797  * With CRm == 0, reg should be one of :
2798  * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1.
2799  */
emulate_id_reg(u32 id,u64 * valp)2800 static inline int emulate_id_reg(u32 id, u64 *valp)
2801 {
2802 	switch (id) {
2803 	case SYS_MIDR_EL1:
2804 		*valp = read_cpuid_id();
2805 		break;
2806 	case SYS_MPIDR_EL1:
2807 		*valp = SYS_MPIDR_SAFE_VAL;
2808 		break;
2809 	case SYS_REVIDR_EL1:
2810 		/* IMPLEMENTATION DEFINED values are emulated with 0 */
2811 		*valp = 0;
2812 		break;
2813 	default:
2814 		return -EINVAL;
2815 	}
2816 
2817 	return 0;
2818 }
2819 
emulate_sys_reg(u32 id,u64 * valp)2820 static int emulate_sys_reg(u32 id, u64 *valp)
2821 {
2822 	struct arm64_ftr_reg *regp;
2823 
2824 	if (!is_emulated(id))
2825 		return -EINVAL;
2826 
2827 	if (sys_reg_CRm(id) == 0)
2828 		return emulate_id_reg(id, valp);
2829 
2830 	regp = get_arm64_ftr_reg_nowarn(id);
2831 	if (regp)
2832 		*valp = arm64_ftr_reg_user_value(regp);
2833 	else
2834 		/*
2835 		 * The untracked registers are either IMPLEMENTATION DEFINED
2836 		 * (e.g, ID_AFR0_EL1) or reserved RAZ.
2837 		 */
2838 		*valp = 0;
2839 	return 0;
2840 }
2841 
do_emulate_mrs(struct pt_regs * regs,u32 sys_reg,u32 rt)2842 int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt)
2843 {
2844 	int rc;
2845 	u64 val;
2846 
2847 	rc = emulate_sys_reg(sys_reg, &val);
2848 	if (!rc) {
2849 		pt_regs_write_reg(regs, rt, val);
2850 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
2851 	}
2852 	return rc;
2853 }
2854 
emulate_mrs(struct pt_regs * regs,u32 insn)2855 static int emulate_mrs(struct pt_regs *regs, u32 insn)
2856 {
2857 	u32 sys_reg, rt;
2858 
2859 	/*
2860 	 * sys_reg values are defined as used in mrs/msr instruction.
2861 	 * shift the imm value to get the encoding.
2862 	 */
2863 	sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5;
2864 	rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn);
2865 	return do_emulate_mrs(regs, sys_reg, rt);
2866 }
2867 
2868 static struct undef_hook mrs_hook = {
2869 	.instr_mask = 0xfff00000,
2870 	.instr_val  = 0xd5300000,
2871 	.pstate_mask = PSR_AA32_MODE_MASK,
2872 	.pstate_val = PSR_MODE_EL0t,
2873 	.fn = emulate_mrs,
2874 };
2875 
enable_mrs_emulation(void)2876 static int __init enable_mrs_emulation(void)
2877 {
2878 	register_undef_hook(&mrs_hook);
2879 	return 0;
2880 }
2881 
2882 core_initcall(enable_mrs_emulation);
2883 
cpu_show_meltdown(struct device * dev,struct device_attribute * attr,char * buf)2884 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
2885 			  char *buf)
2886 {
2887 	if (__meltdown_safe)
2888 		return sprintf(buf, "Not affected\n");
2889 
2890 	if (arm64_kernel_unmapped_at_el0())
2891 		return sprintf(buf, "Mitigation: PTI\n");
2892 
2893 	return sprintf(buf, "Vulnerable\n");
2894 }
2895