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 /* Masks for extracting the FPSR and FPCR from the FPSCR */ 25 #define VFP_FPSCR_STAT_MASK 0xf800009f 26 #define VFP_FPSCR_CTRL_MASK 0x07f79f00 27 /* 28 * The VFP state has 32x64-bit registers and a single 32-bit 29 * control/status register. 30 */ 31 #define VFP_STATE_SIZE ((32 * 8) + 4) 32 33 static inline unsigned long cpacr_save_enable_kernel_sve(void) 34 { 35 unsigned long old = read_sysreg(cpacr_el1); 36 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_ZEN_EL1EN; 37 38 write_sysreg(old | set, cpacr_el1); 39 isb(); 40 return old; 41 } 42 43 static inline unsigned long cpacr_save_enable_kernel_sme(void) 44 { 45 unsigned long old = read_sysreg(cpacr_el1); 46 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_SMEN_EL1EN; 47 48 write_sysreg(old | set, cpacr_el1); 49 isb(); 50 return old; 51 } 52 53 static inline void cpacr_restore(unsigned long cpacr) 54 { 55 write_sysreg(cpacr, cpacr_el1); 56 isb(); 57 } 58 59 /* 60 * When we defined the maximum SVE vector length we defined the ABI so 61 * that the maximum vector length included all the reserved for future 62 * expansion bits in ZCR rather than those just currently defined by 63 * the architecture. Using this length to allocate worst size buffers 64 * results in excessively large allocations, and this effect is even 65 * more pronounced for SME due to ZA. Define more suitable VLs for 66 * these situations. 67 */ 68 #define ARCH_SVE_VQ_MAX ((ZCR_ELx_LEN_MASK >> ZCR_ELx_LEN_SHIFT) + 1) 69 #define SME_VQ_MAX ((SMCR_ELx_LEN_MASK >> SMCR_ELx_LEN_SHIFT) + 1) 70 71 struct task_struct; 72 73 extern void fpsimd_save_state(struct user_fpsimd_state *state); 74 extern void fpsimd_load_state(struct user_fpsimd_state *state); 75 76 extern void fpsimd_thread_switch(struct task_struct *next); 77 extern void fpsimd_flush_thread(void); 78 79 extern void fpsimd_signal_preserve_current_state(void); 80 extern void fpsimd_preserve_current_state(void); 81 extern void fpsimd_restore_current_state(void); 82 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state); 83 84 struct cpu_fp_state { 85 struct user_fpsimd_state *st; 86 void *sve_state; 87 void *sme_state; 88 u64 *svcr; 89 u64 *fpmr; 90 unsigned int sve_vl; 91 unsigned int sme_vl; 92 enum fp_type *fp_type; 93 enum fp_type to_save; 94 }; 95 96 extern void fpsimd_bind_state_to_cpu(struct cpu_fp_state *fp_state); 97 98 extern void fpsimd_flush_task_state(struct task_struct *target); 99 extern void fpsimd_save_and_flush_cpu_state(void); 100 101 static inline bool thread_sm_enabled(struct thread_struct *thread) 102 { 103 return system_supports_sme() && (thread->svcr & SVCR_SM_MASK); 104 } 105 106 static inline bool thread_za_enabled(struct thread_struct *thread) 107 { 108 return system_supports_sme() && (thread->svcr & SVCR_ZA_MASK); 109 } 110 111 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */ 112 #define VL_ARCH_MAX 0x100 113 114 /* Offset of FFR in the SVE register dump */ 115 static inline size_t sve_ffr_offset(int vl) 116 { 117 return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET; 118 } 119 120 static inline void *sve_pffr(struct thread_struct *thread) 121 { 122 unsigned int vl; 123 124 if (system_supports_sme() && thread_sm_enabled(thread)) 125 vl = thread_get_sme_vl(thread); 126 else 127 vl = thread_get_sve_vl(thread); 128 129 return (char *)thread->sve_state + sve_ffr_offset(vl); 130 } 131 132 static inline void *thread_zt_state(struct thread_struct *thread) 133 { 134 /* The ZT register state is stored immediately after the ZA state */ 135 unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread)); 136 return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq); 137 } 138 139 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr); 140 extern void sve_load_state(void const *state, u32 const *pfpsr, 141 int restore_ffr); 142 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1); 143 extern unsigned int sve_get_vl(void); 144 extern void sve_set_vq(unsigned long vq_minus_1); 145 extern void sme_set_vq(unsigned long vq_minus_1); 146 extern void sme_save_state(void *state, int zt); 147 extern void sme_load_state(void const *state, int zt); 148 149 struct arm64_cpu_capabilities; 150 extern void cpu_enable_fpsimd(const struct arm64_cpu_capabilities *__unused); 151 extern void cpu_enable_sve(const struct arm64_cpu_capabilities *__unused); 152 extern void cpu_enable_sme(const struct arm64_cpu_capabilities *__unused); 153 extern void cpu_enable_sme2(const struct arm64_cpu_capabilities *__unused); 154 extern void cpu_enable_fa64(const struct arm64_cpu_capabilities *__unused); 155 extern void cpu_enable_fpmr(const struct arm64_cpu_capabilities *__unused); 156 157 /* 158 * Helpers to translate bit indices in sve_vq_map to VQ values (and 159 * vice versa). This allows find_next_bit() to be used to find the 160 * _maximum_ VQ not exceeding a certain value. 161 */ 162 static inline unsigned int __vq_to_bit(unsigned int vq) 163 { 164 return SVE_VQ_MAX - vq; 165 } 166 167 static inline unsigned int __bit_to_vq(unsigned int bit) 168 { 169 return SVE_VQ_MAX - bit; 170 } 171 172 173 struct vl_info { 174 enum vec_type type; 175 const char *name; /* For display purposes */ 176 177 /* Minimum supported vector length across all CPUs */ 178 int min_vl; 179 180 /* Maximum supported vector length across all CPUs */ 181 int max_vl; 182 int max_virtualisable_vl; 183 184 /* 185 * Set of available vector lengths, 186 * where length vq encoded as bit __vq_to_bit(vq): 187 */ 188 DECLARE_BITMAP(vq_map, SVE_VQ_MAX); 189 190 /* Set of vector lengths present on at least one cpu: */ 191 DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX); 192 }; 193 194 #ifdef CONFIG_ARM64_SVE 195 196 extern void sve_alloc(struct task_struct *task, bool flush); 197 extern void fpsimd_release_task(struct task_struct *task); 198 extern void fpsimd_sync_to_sve(struct task_struct *task); 199 extern void fpsimd_force_sync_to_sve(struct task_struct *task); 200 extern void sve_sync_to_fpsimd(struct task_struct *task); 201 extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task); 202 203 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type, 204 unsigned long vl, unsigned long flags); 205 206 extern int sve_set_current_vl(unsigned long arg); 207 extern int sve_get_current_vl(void); 208 209 static inline void sve_user_disable(void) 210 { 211 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0); 212 } 213 214 static inline void sve_user_enable(void) 215 { 216 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN); 217 } 218 219 #define sve_cond_update_zcr_vq(val, reg) \ 220 do { \ 221 u64 __zcr = read_sysreg_s((reg)); \ 222 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \ 223 __new |= (val) & ZCR_ELx_LEN_MASK; \ 224 if (__zcr != __new) \ 225 write_sysreg_s(__new, (reg)); \ 226 } while (0) 227 228 /* 229 * Probing and setup functions. 230 * Calls to these functions must be serialised with one another. 231 */ 232 enum vec_type; 233 234 extern void __init vec_init_vq_map(enum vec_type type); 235 extern void vec_update_vq_map(enum vec_type type); 236 extern int vec_verify_vq_map(enum vec_type type); 237 extern void __init sve_setup(void); 238 239 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX]; 240 241 static inline void write_vl(enum vec_type type, u64 val) 242 { 243 u64 tmp; 244 245 switch (type) { 246 #ifdef CONFIG_ARM64_SVE 247 case ARM64_VEC_SVE: 248 tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK; 249 write_sysreg_s(tmp | val, SYS_ZCR_EL1); 250 break; 251 #endif 252 #ifdef CONFIG_ARM64_SME 253 case ARM64_VEC_SME: 254 tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK; 255 write_sysreg_s(tmp | val, SYS_SMCR_EL1); 256 break; 257 #endif 258 default: 259 WARN_ON_ONCE(1); 260 break; 261 } 262 } 263 264 static inline int vec_max_vl(enum vec_type type) 265 { 266 return vl_info[type].max_vl; 267 } 268 269 static inline int vec_max_virtualisable_vl(enum vec_type type) 270 { 271 return vl_info[type].max_virtualisable_vl; 272 } 273 274 static inline int sve_max_vl(void) 275 { 276 return vec_max_vl(ARM64_VEC_SVE); 277 } 278 279 static inline int sve_max_virtualisable_vl(void) 280 { 281 return vec_max_virtualisable_vl(ARM64_VEC_SVE); 282 } 283 284 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */ 285 static inline bool vq_available(enum vec_type type, unsigned int vq) 286 { 287 return test_bit(__vq_to_bit(vq), vl_info[type].vq_map); 288 } 289 290 static inline bool sve_vq_available(unsigned int vq) 291 { 292 return vq_available(ARM64_VEC_SVE, vq); 293 } 294 295 size_t sve_state_size(struct task_struct const *task); 296 297 #else /* ! CONFIG_ARM64_SVE */ 298 299 static inline void sve_alloc(struct task_struct *task, bool flush) { } 300 static inline void fpsimd_release_task(struct task_struct *task) { } 301 static inline void sve_sync_to_fpsimd(struct task_struct *task) { } 302 static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { } 303 304 static inline int sve_max_virtualisable_vl(void) 305 { 306 return 0; 307 } 308 309 static inline int sve_set_current_vl(unsigned long arg) 310 { 311 return -EINVAL; 312 } 313 314 static inline int sve_get_current_vl(void) 315 { 316 return -EINVAL; 317 } 318 319 static inline int sve_max_vl(void) 320 { 321 return -EINVAL; 322 } 323 324 static inline bool sve_vq_available(unsigned int vq) { return false; } 325 326 static inline void sve_user_disable(void) { BUILD_BUG(); } 327 static inline void sve_user_enable(void) { BUILD_BUG(); } 328 329 #define sve_cond_update_zcr_vq(val, reg) do { } while (0) 330 331 static inline void vec_init_vq_map(enum vec_type t) { } 332 static inline void vec_update_vq_map(enum vec_type t) { } 333 static inline int vec_verify_vq_map(enum vec_type t) { return 0; } 334 static inline void sve_setup(void) { } 335 336 static inline size_t sve_state_size(struct task_struct const *task) 337 { 338 return 0; 339 } 340 341 #endif /* ! CONFIG_ARM64_SVE */ 342 343 #ifdef CONFIG_ARM64_SME 344 345 static inline void sme_user_disable(void) 346 { 347 sysreg_clear_set(cpacr_el1, CPACR_EL1_SMEN_EL0EN, 0); 348 } 349 350 static inline void sme_user_enable(void) 351 { 352 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_SMEN_EL0EN); 353 } 354 355 static inline void sme_smstart_sm(void) 356 { 357 asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr")); 358 } 359 360 static inline void sme_smstop_sm(void) 361 { 362 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr")); 363 } 364 365 static inline void sme_smstop(void) 366 { 367 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr")); 368 } 369 370 extern void __init sme_setup(void); 371 372 static inline int sme_max_vl(void) 373 { 374 return vec_max_vl(ARM64_VEC_SME); 375 } 376 377 static inline int sme_max_virtualisable_vl(void) 378 { 379 return vec_max_virtualisable_vl(ARM64_VEC_SME); 380 } 381 382 extern void sme_alloc(struct task_struct *task, bool flush); 383 extern unsigned int sme_get_vl(void); 384 extern int sme_set_current_vl(unsigned long arg); 385 extern int sme_get_current_vl(void); 386 extern void sme_suspend_exit(void); 387 388 /* 389 * Return how many bytes of memory are required to store the full SME 390 * specific state for task, given task's currently configured vector 391 * length. 392 */ 393 static inline size_t sme_state_size(struct task_struct const *task) 394 { 395 unsigned int vl = task_get_sme_vl(task); 396 size_t size; 397 398 size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl)); 399 400 if (system_supports_sme2()) 401 size += ZT_SIG_REG_SIZE; 402 403 return size; 404 } 405 406 #else 407 408 static inline void sme_user_disable(void) { BUILD_BUG(); } 409 static inline void sme_user_enable(void) { BUILD_BUG(); } 410 411 static inline void sme_smstart_sm(void) { } 412 static inline void sme_smstop_sm(void) { } 413 static inline void sme_smstop(void) { } 414 415 static inline void sme_alloc(struct task_struct *task, bool flush) { } 416 static inline void sme_setup(void) { } 417 static inline unsigned int sme_get_vl(void) { return 0; } 418 static inline int sme_max_vl(void) { return 0; } 419 static inline int sme_max_virtualisable_vl(void) { return 0; } 420 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; } 421 static inline int sme_get_current_vl(void) { return -EINVAL; } 422 static inline void sme_suspend_exit(void) { } 423 424 static inline size_t sme_state_size(struct task_struct const *task) 425 { 426 return 0; 427 } 428 429 #endif /* ! CONFIG_ARM64_SME */ 430 431 /* For use by EFI runtime services calls only */ 432 extern void __efi_fpsimd_begin(void); 433 extern void __efi_fpsimd_end(void); 434 435 #endif 436 437 #endif 438