1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012 ARM Ltd. 4 */ 5 #ifndef __ASM_FP_H 6 #define __ASM_FP_H 7 8 #include <asm/errno.h> 9 #include <asm/ptrace.h> 10 #include <asm/processor.h> 11 #include <asm/sigcontext.h> 12 #include <asm/sysreg.h> 13 14 #ifndef __ASSEMBLY__ 15 16 #include <linux/bitmap.h> 17 #include <linux/build_bug.h> 18 #include <linux/bug.h> 19 #include <linux/cache.h> 20 #include <linux/init.h> 21 #include <linux/stddef.h> 22 #include <linux/types.h> 23 24 #ifdef CONFIG_COMPAT 25 /* Masks for extracting the FPSR and FPCR from the FPSCR */ 26 #define VFP_FPSCR_STAT_MASK 0xf800009f 27 #define VFP_FPSCR_CTRL_MASK 0x07f79f00 28 /* 29 * The VFP state has 32x64-bit registers and a single 32-bit 30 * control/status register. 31 */ 32 #define VFP_STATE_SIZE ((32 * 8) + 4) 33 #endif 34 35 /* 36 * When we defined the maximum SVE vector length we defined the ABI so 37 * that the maximum vector length included all the reserved for future 38 * expansion bits in ZCR rather than those just currently defined by 39 * the architecture. While SME follows a similar pattern the fact that 40 * it includes a square matrix means that any allocations that attempt 41 * to cover the maximum potential vector length (such as happen with 42 * the regset used for ptrace) end up being extremely large. Define 43 * the much lower actual limit for use in such situations. 44 */ 45 #define SME_VQ_MAX 16 46 47 struct task_struct; 48 49 extern void fpsimd_save_state(struct user_fpsimd_state *state); 50 extern void fpsimd_load_state(struct user_fpsimd_state *state); 51 52 extern void fpsimd_thread_switch(struct task_struct *next); 53 extern void fpsimd_flush_thread(void); 54 55 extern void fpsimd_signal_preserve_current_state(void); 56 extern void fpsimd_preserve_current_state(void); 57 extern void fpsimd_restore_current_state(void); 58 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state); 59 extern void fpsimd_kvm_prepare(void); 60 61 struct cpu_fp_state { 62 struct user_fpsimd_state *st; 63 void *sve_state; 64 void *sme_state; 65 u64 *svcr; 66 unsigned int sve_vl; 67 unsigned int sme_vl; 68 enum fp_type *fp_type; 69 enum fp_type to_save; 70 }; 71 72 extern void fpsimd_bind_state_to_cpu(struct cpu_fp_state *fp_state); 73 74 extern void fpsimd_flush_task_state(struct task_struct *target); 75 extern void fpsimd_save_and_flush_cpu_state(void); 76 77 static inline bool thread_sm_enabled(struct thread_struct *thread) 78 { 79 return system_supports_sme() && (thread->svcr & SVCR_SM_MASK); 80 } 81 82 static inline bool thread_za_enabled(struct thread_struct *thread) 83 { 84 return system_supports_sme() && (thread->svcr & SVCR_ZA_MASK); 85 } 86 87 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */ 88 #define VL_ARCH_MAX 0x100 89 90 /* Offset of FFR in the SVE register dump */ 91 static inline size_t sve_ffr_offset(int vl) 92 { 93 return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET; 94 } 95 96 static inline void *sve_pffr(struct thread_struct *thread) 97 { 98 unsigned int vl; 99 100 if (system_supports_sme() && thread_sm_enabled(thread)) 101 vl = thread_get_sme_vl(thread); 102 else 103 vl = thread_get_sve_vl(thread); 104 105 return (char *)thread->sve_state + sve_ffr_offset(vl); 106 } 107 108 static inline void *thread_zt_state(struct thread_struct *thread) 109 { 110 /* The ZT register state is stored immediately after the ZA state */ 111 unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread)); 112 return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq); 113 } 114 115 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr); 116 extern void sve_load_state(void const *state, u32 const *pfpsr, 117 int restore_ffr); 118 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1); 119 extern unsigned int sve_get_vl(void); 120 extern void sve_set_vq(unsigned long vq_minus_1); 121 extern void sme_set_vq(unsigned long vq_minus_1); 122 extern void sme_save_state(void *state, int zt); 123 extern void sme_load_state(void const *state, int zt); 124 125 struct arm64_cpu_capabilities; 126 extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused); 127 extern void sme_kernel_enable(const struct arm64_cpu_capabilities *__unused); 128 extern void sme2_kernel_enable(const struct arm64_cpu_capabilities *__unused); 129 extern void fa64_kernel_enable(const struct arm64_cpu_capabilities *__unused); 130 131 extern u64 read_zcr_features(void); 132 extern u64 read_smcr_features(void); 133 134 /* 135 * Helpers to translate bit indices in sve_vq_map to VQ values (and 136 * vice versa). This allows find_next_bit() to be used to find the 137 * _maximum_ VQ not exceeding a certain value. 138 */ 139 static inline unsigned int __vq_to_bit(unsigned int vq) 140 { 141 return SVE_VQ_MAX - vq; 142 } 143 144 static inline unsigned int __bit_to_vq(unsigned int bit) 145 { 146 return SVE_VQ_MAX - bit; 147 } 148 149 150 struct vl_info { 151 enum vec_type type; 152 const char *name; /* For display purposes */ 153 154 /* Minimum supported vector length across all CPUs */ 155 int min_vl; 156 157 /* Maximum supported vector length across all CPUs */ 158 int max_vl; 159 int max_virtualisable_vl; 160 161 /* 162 * Set of available vector lengths, 163 * where length vq encoded as bit __vq_to_bit(vq): 164 */ 165 DECLARE_BITMAP(vq_map, SVE_VQ_MAX); 166 167 /* Set of vector lengths present on at least one cpu: */ 168 DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX); 169 }; 170 171 #ifdef CONFIG_ARM64_SVE 172 173 extern void sve_alloc(struct task_struct *task, bool flush); 174 extern void fpsimd_release_task(struct task_struct *task); 175 extern void fpsimd_sync_to_sve(struct task_struct *task); 176 extern void fpsimd_force_sync_to_sve(struct task_struct *task); 177 extern void sve_sync_to_fpsimd(struct task_struct *task); 178 extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task); 179 180 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type, 181 unsigned long vl, unsigned long flags); 182 183 extern int sve_set_current_vl(unsigned long arg); 184 extern int sve_get_current_vl(void); 185 186 static inline void sve_user_disable(void) 187 { 188 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0); 189 } 190 191 static inline void sve_user_enable(void) 192 { 193 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN); 194 } 195 196 #define sve_cond_update_zcr_vq(val, reg) \ 197 do { \ 198 u64 __zcr = read_sysreg_s((reg)); \ 199 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \ 200 __new |= (val) & ZCR_ELx_LEN_MASK; \ 201 if (__zcr != __new) \ 202 write_sysreg_s(__new, (reg)); \ 203 } while (0) 204 205 /* 206 * Probing and setup functions. 207 * Calls to these functions must be serialised with one another. 208 */ 209 enum vec_type; 210 211 extern void __init vec_init_vq_map(enum vec_type type); 212 extern void vec_update_vq_map(enum vec_type type); 213 extern int vec_verify_vq_map(enum vec_type type); 214 extern void __init sve_setup(void); 215 216 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX]; 217 218 static inline void write_vl(enum vec_type type, u64 val) 219 { 220 u64 tmp; 221 222 switch (type) { 223 #ifdef CONFIG_ARM64_SVE 224 case ARM64_VEC_SVE: 225 tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK; 226 write_sysreg_s(tmp | val, SYS_ZCR_EL1); 227 break; 228 #endif 229 #ifdef CONFIG_ARM64_SME 230 case ARM64_VEC_SME: 231 tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK; 232 write_sysreg_s(tmp | val, SYS_SMCR_EL1); 233 break; 234 #endif 235 default: 236 WARN_ON_ONCE(1); 237 break; 238 } 239 } 240 241 static inline int vec_max_vl(enum vec_type type) 242 { 243 return vl_info[type].max_vl; 244 } 245 246 static inline int vec_max_virtualisable_vl(enum vec_type type) 247 { 248 return vl_info[type].max_virtualisable_vl; 249 } 250 251 static inline int sve_max_vl(void) 252 { 253 return vec_max_vl(ARM64_VEC_SVE); 254 } 255 256 static inline int sve_max_virtualisable_vl(void) 257 { 258 return vec_max_virtualisable_vl(ARM64_VEC_SVE); 259 } 260 261 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */ 262 static inline bool vq_available(enum vec_type type, unsigned int vq) 263 { 264 return test_bit(__vq_to_bit(vq), vl_info[type].vq_map); 265 } 266 267 static inline bool sve_vq_available(unsigned int vq) 268 { 269 return vq_available(ARM64_VEC_SVE, vq); 270 } 271 272 size_t sve_state_size(struct task_struct const *task); 273 274 #else /* ! CONFIG_ARM64_SVE */ 275 276 static inline void sve_alloc(struct task_struct *task, bool flush) { } 277 static inline void fpsimd_release_task(struct task_struct *task) { } 278 static inline void sve_sync_to_fpsimd(struct task_struct *task) { } 279 static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { } 280 281 static inline int sve_max_virtualisable_vl(void) 282 { 283 return 0; 284 } 285 286 static inline int sve_set_current_vl(unsigned long arg) 287 { 288 return -EINVAL; 289 } 290 291 static inline int sve_get_current_vl(void) 292 { 293 return -EINVAL; 294 } 295 296 static inline int sve_max_vl(void) 297 { 298 return -EINVAL; 299 } 300 301 static inline bool sve_vq_available(unsigned int vq) { return false; } 302 303 static inline void sve_user_disable(void) { BUILD_BUG(); } 304 static inline void sve_user_enable(void) { BUILD_BUG(); } 305 306 #define sve_cond_update_zcr_vq(val, reg) do { } while (0) 307 308 static inline void vec_init_vq_map(enum vec_type t) { } 309 static inline void vec_update_vq_map(enum vec_type t) { } 310 static inline int vec_verify_vq_map(enum vec_type t) { return 0; } 311 static inline void sve_setup(void) { } 312 313 static inline size_t sve_state_size(struct task_struct const *task) 314 { 315 return 0; 316 } 317 318 #endif /* ! CONFIG_ARM64_SVE */ 319 320 #ifdef CONFIG_ARM64_SME 321 322 static inline void sme_user_disable(void) 323 { 324 sysreg_clear_set(cpacr_el1, CPACR_EL1_SMEN_EL0EN, 0); 325 } 326 327 static inline void sme_user_enable(void) 328 { 329 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_SMEN_EL0EN); 330 } 331 332 static inline void sme_smstart_sm(void) 333 { 334 asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr")); 335 } 336 337 static inline void sme_smstop_sm(void) 338 { 339 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr")); 340 } 341 342 static inline void sme_smstop(void) 343 { 344 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr")); 345 } 346 347 extern void __init sme_setup(void); 348 349 static inline int sme_max_vl(void) 350 { 351 return vec_max_vl(ARM64_VEC_SME); 352 } 353 354 static inline int sme_max_virtualisable_vl(void) 355 { 356 return vec_max_virtualisable_vl(ARM64_VEC_SME); 357 } 358 359 extern void sme_alloc(struct task_struct *task); 360 extern unsigned int sme_get_vl(void); 361 extern int sme_set_current_vl(unsigned long arg); 362 extern int sme_get_current_vl(void); 363 364 /* 365 * Return how many bytes of memory are required to store the full SME 366 * specific state for task, given task's currently configured vector 367 * length. 368 */ 369 static inline size_t sme_state_size(struct task_struct const *task) 370 { 371 unsigned int vl = task_get_sme_vl(task); 372 size_t size; 373 374 size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl)); 375 376 if (system_supports_sme2()) 377 size += ZT_SIG_REG_SIZE; 378 379 return size; 380 } 381 382 #else 383 384 static inline void sme_user_disable(void) { BUILD_BUG(); } 385 static inline void sme_user_enable(void) { BUILD_BUG(); } 386 387 static inline void sme_smstart_sm(void) { } 388 static inline void sme_smstop_sm(void) { } 389 static inline void sme_smstop(void) { } 390 391 static inline void sme_alloc(struct task_struct *task) { } 392 static inline void sme_setup(void) { } 393 static inline unsigned int sme_get_vl(void) { return 0; } 394 static inline int sme_max_vl(void) { return 0; } 395 static inline int sme_max_virtualisable_vl(void) { return 0; } 396 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; } 397 static inline int sme_get_current_vl(void) { return -EINVAL; } 398 399 static inline size_t sme_state_size(struct task_struct const *task) 400 { 401 return 0; 402 } 403 404 #endif /* ! CONFIG_ARM64_SME */ 405 406 /* For use by EFI runtime services calls only */ 407 extern void __efi_fpsimd_begin(void); 408 extern void __efi_fpsimd_end(void); 409 410 #endif 411 412 #endif 413