1 /* 2 * Copyright (c) 2016-2021, ARM Limited and Contributors. All rights reserved. 3 * Portions copyright (c) 2021-2022, ProvenRun S.A.S. All rights reserved. 4 * 5 * SPDX-License-Identifier: BSD-3-Clause 6 */ 7 8 #ifndef ARCH_HELPERS_H 9 #define ARCH_HELPERS_H 10 11 #include <assert.h> 12 #include <cdefs.h> 13 #include <stdbool.h> 14 #include <stdint.h> 15 #include <string.h> 16 17 #include <arch.h> 18 19 /********************************************************************** 20 * Macros which create inline functions to read or write CPU system 21 * registers 22 *********************************************************************/ 23 24 #define _DEFINE_COPROCR_WRITE_FUNC(_name, coproc, opc1, CRn, CRm, opc2) \ 25 static inline void write_## _name(u_register_t v) \ 26 { \ 27 __asm__ volatile ("mcr "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : : "r" (v));\ 28 } 29 30 #define _DEFINE_COPROCR_READ_FUNC(_name, coproc, opc1, CRn, CRm, opc2) \ 31 static inline u_register_t read_ ## _name(void) \ 32 { \ 33 u_register_t v; \ 34 __asm__ volatile ("mrc "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : "=r" (v));\ 35 return v; \ 36 } 37 38 /* 39 * The undocumented %Q and %R extended asm are used to implemented the below 40 * 64 bit `mrrc` and `mcrr` instructions. 41 */ 42 43 #define _DEFINE_COPROCR_WRITE_FUNC_64(_name, coproc, opc1, CRm) \ 44 static inline void write64_## _name(uint64_t v) \ 45 { \ 46 __asm__ volatile ("mcrr "#coproc","#opc1", %Q0, %R0,"#CRm : : "r" (v));\ 47 } 48 49 #define _DEFINE_COPROCR_READ_FUNC_64(_name, coproc, opc1, CRm) \ 50 static inline uint64_t read64_## _name(void) \ 51 { uint64_t v; \ 52 __asm__ volatile ("mrrc "#coproc","#opc1", %Q0, %R0,"#CRm : "=r" (v));\ 53 return v; \ 54 } 55 56 #define _DEFINE_SYSREG_READ_FUNC(_name, _reg_name) \ 57 static inline u_register_t read_ ## _name(void) \ 58 { \ 59 u_register_t v; \ 60 __asm__ volatile ("mrs %0, " #_reg_name : "=r" (v)); \ 61 return v; \ 62 } 63 64 #define _DEFINE_SYSREG_WRITE_FUNC(_name, _reg_name) \ 65 static inline void write_ ## _name(u_register_t v) \ 66 { \ 67 __asm__ volatile ("msr " #_reg_name ", %0" : : "r" (v)); \ 68 } 69 70 #define _DEFINE_SYSREG_WRITE_CONST_FUNC(_name, _reg_name) \ 71 static inline void write_ ## _name(const u_register_t v) \ 72 { \ 73 __asm__ volatile ("msr " #_reg_name ", %0" : : "i" (v)); \ 74 } 75 76 /* Define read function for coproc register */ 77 #define DEFINE_COPROCR_READ_FUNC(_name, ...) \ 78 _DEFINE_COPROCR_READ_FUNC(_name, __VA_ARGS__) 79 80 /* Define write function for coproc register */ 81 #define DEFINE_COPROCR_WRITE_FUNC(_name, ...) \ 82 _DEFINE_COPROCR_WRITE_FUNC(_name, __VA_ARGS__) 83 84 /* Define read & write function for coproc register */ 85 #define DEFINE_COPROCR_RW_FUNCS(_name, ...) \ 86 _DEFINE_COPROCR_READ_FUNC(_name, __VA_ARGS__) \ 87 _DEFINE_COPROCR_WRITE_FUNC(_name, __VA_ARGS__) 88 89 /* Define 64 bit read function for coproc register */ 90 #define DEFINE_COPROCR_READ_FUNC_64(_name, ...) \ 91 _DEFINE_COPROCR_READ_FUNC_64(_name, __VA_ARGS__) 92 93 /* Define 64 bit write function for coproc register */ 94 #define DEFINE_COPROCR_WRITE_FUNC_64(_name, ...) \ 95 _DEFINE_COPROCR_WRITE_FUNC_64(_name, __VA_ARGS__) 96 97 /* Define 64 bit read & write function for coproc register */ 98 #define DEFINE_COPROCR_RW_FUNCS_64(_name, ...) \ 99 _DEFINE_COPROCR_READ_FUNC_64(_name, __VA_ARGS__) \ 100 _DEFINE_COPROCR_WRITE_FUNC_64(_name, __VA_ARGS__) 101 102 /* Define read & write function for system register */ 103 #define DEFINE_SYSREG_RW_FUNCS(_name) \ 104 _DEFINE_SYSREG_READ_FUNC(_name, _name) \ 105 _DEFINE_SYSREG_WRITE_FUNC(_name, _name) 106 107 /********************************************************************** 108 * Macros to create inline functions for tlbi operations 109 *********************************************************************/ 110 111 #define _DEFINE_TLBIOP_FUNC(_op, coproc, opc1, CRn, CRm, opc2) \ 112 static inline void tlbi##_op(void) \ 113 { \ 114 u_register_t v = 0; \ 115 __asm__ volatile ("mcr "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : : "r" (v));\ 116 } 117 118 #define _DEFINE_BPIOP_FUNC(_op, coproc, opc1, CRn, CRm, opc2) \ 119 static inline void bpi##_op(void) \ 120 { \ 121 u_register_t v = 0; \ 122 __asm__ volatile ("mcr "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : : "r" (v));\ 123 } 124 125 #define _DEFINE_TLBIOP_PARAM_FUNC(_op, coproc, opc1, CRn, CRm, opc2) \ 126 static inline void tlbi##_op(u_register_t v) \ 127 { \ 128 __asm__ volatile ("mcr "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : : "r" (v));\ 129 } 130 131 /* Define function for simple TLBI operation */ 132 #define DEFINE_TLBIOP_FUNC(_op, ...) \ 133 _DEFINE_TLBIOP_FUNC(_op, __VA_ARGS__) 134 135 /* Define function for TLBI operation with register parameter */ 136 #define DEFINE_TLBIOP_PARAM_FUNC(_op, ...) \ 137 _DEFINE_TLBIOP_PARAM_FUNC(_op, __VA_ARGS__) 138 139 /* Define function for simple BPI operation */ 140 #define DEFINE_BPIOP_FUNC(_op, ...) \ 141 _DEFINE_BPIOP_FUNC(_op, __VA_ARGS__) 142 143 /********************************************************************** 144 * Macros to create inline functions for DC operations 145 *********************************************************************/ 146 #define _DEFINE_DCOP_PARAM_FUNC(_op, coproc, opc1, CRn, CRm, opc2) \ 147 static inline void dc##_op(u_register_t v) \ 148 { \ 149 __asm__ volatile ("mcr "#coproc","#opc1",%0,"#CRn","#CRm","#opc2 : : "r" (v));\ 150 } 151 152 /* Define function for DC operation with register parameter */ 153 #define DEFINE_DCOP_PARAM_FUNC(_op, ...) \ 154 _DEFINE_DCOP_PARAM_FUNC(_op, __VA_ARGS__) 155 156 /********************************************************************** 157 * Macros to create inline functions for system instructions 158 *********************************************************************/ 159 /* Define function for simple system instruction */ 160 #define DEFINE_SYSOP_FUNC(_op) \ 161 static inline void _op(void) \ 162 { \ 163 __asm__ (#_op); \ 164 } 165 166 167 /* Define function for system instruction with type specifier */ 168 #define DEFINE_SYSOP_TYPE_FUNC(_op, _type) \ 169 static inline void _op ## _type(void) \ 170 { \ 171 __asm__ (#_op " " #_type : : : "memory"); \ 172 } 173 174 /* Define function for system instruction with register parameter */ 175 #define DEFINE_SYSOP_TYPE_PARAM_FUNC(_op, _type) \ 176 static inline void _op ## _type(u_register_t v) \ 177 { \ 178 __asm__ (#_op " " #_type ", %0" : : "r" (v)); \ 179 } 180 181 void flush_dcache_range(uintptr_t addr, size_t size); 182 void clean_dcache_range(uintptr_t addr, size_t size); 183 void inv_dcache_range(uintptr_t addr, size_t size); 184 bool is_dcache_enabled(void); 185 186 void dcsw_op_louis(u_register_t op_type); 187 void dcsw_op_all(u_register_t op_type); 188 189 void disable_mmu_secure(void); 190 void disable_mmu_icache_secure(void); 191 192 DEFINE_SYSOP_FUNC(wfi) 193 DEFINE_SYSOP_FUNC(wfe) 194 DEFINE_SYSOP_FUNC(sev) 195 DEFINE_SYSOP_TYPE_FUNC(dsb, sy) 196 DEFINE_SYSOP_TYPE_FUNC(dmb, sy) 197 DEFINE_SYSOP_TYPE_FUNC(dmb, st) 198 199 /* dmb ld is not valid for armv7/thumb machines */ 200 #if ARM_ARCH_MAJOR != 7 201 DEFINE_SYSOP_TYPE_FUNC(dmb, ld) 202 #endif 203 204 DEFINE_SYSOP_TYPE_FUNC(dsb, ish) 205 DEFINE_SYSOP_TYPE_FUNC(dsb, ishst) 206 DEFINE_SYSOP_TYPE_FUNC(dmb, ish) 207 DEFINE_SYSOP_TYPE_FUNC(dmb, ishst) 208 DEFINE_SYSOP_FUNC(isb) 209 210 void __dead2 smc(uint32_t r0, uint32_t r1, uint32_t r2, uint32_t r3, 211 uint32_t r4, uint32_t r5, uint32_t r6, uint32_t r7); 212 213 DEFINE_SYSREG_RW_FUNCS(spsr) 214 DEFINE_SYSREG_RW_FUNCS(cpsr) 215 216 /******************************************************************************* 217 * System register accessor prototypes 218 ******************************************************************************/ 219 DEFINE_COPROCR_READ_FUNC(mpidr, MPIDR) 220 DEFINE_COPROCR_READ_FUNC(midr, MIDR) 221 DEFINE_COPROCR_READ_FUNC(id_mmfr3, ID_MMFR3) 222 DEFINE_COPROCR_READ_FUNC(id_mmfr4, ID_MMFR4) 223 DEFINE_COPROCR_READ_FUNC(id_dfr0, ID_DFR0) 224 DEFINE_COPROCR_READ_FUNC(id_dfr1, ID_DFR1) 225 DEFINE_COPROCR_READ_FUNC(id_pfr0, ID_PFR0) 226 DEFINE_COPROCR_READ_FUNC(id_pfr1, ID_PFR1) 227 DEFINE_COPROCR_READ_FUNC(isr, ISR) 228 DEFINE_COPROCR_READ_FUNC(clidr, CLIDR) 229 DEFINE_COPROCR_READ_FUNC_64(cntpct, CNTPCT_64) 230 231 DEFINE_COPROCR_RW_FUNCS(scr, SCR) 232 DEFINE_COPROCR_RW_FUNCS(ctr, CTR) 233 DEFINE_COPROCR_RW_FUNCS(sctlr, SCTLR) 234 DEFINE_COPROCR_RW_FUNCS(actlr, ACTLR) 235 DEFINE_COPROCR_RW_FUNCS(hsctlr, HSCTLR) 236 DEFINE_COPROCR_RW_FUNCS(hcr, HCR) 237 DEFINE_COPROCR_RW_FUNCS(hcptr, HCPTR) 238 DEFINE_COPROCR_RW_FUNCS(cntfrq, CNTFRQ) 239 DEFINE_COPROCR_RW_FUNCS(cnthctl, CNTHCTL) 240 DEFINE_COPROCR_RW_FUNCS(mair0, MAIR0) 241 DEFINE_COPROCR_RW_FUNCS(mair1, MAIR1) 242 DEFINE_COPROCR_RW_FUNCS(hmair0, HMAIR0) 243 DEFINE_COPROCR_RW_FUNCS(ttbcr, TTBCR) 244 DEFINE_COPROCR_RW_FUNCS(htcr, HTCR) 245 DEFINE_COPROCR_RW_FUNCS(ttbr0, TTBR0) 246 DEFINE_COPROCR_RW_FUNCS_64(ttbr0, TTBR0_64) 247 DEFINE_COPROCR_RW_FUNCS(ttbr1, TTBR1) 248 DEFINE_COPROCR_RW_FUNCS_64(httbr, HTTBR_64) 249 DEFINE_COPROCR_RW_FUNCS(vpidr, VPIDR) 250 DEFINE_COPROCR_RW_FUNCS(vmpidr, VMPIDR) 251 DEFINE_COPROCR_RW_FUNCS_64(vttbr, VTTBR_64) 252 DEFINE_COPROCR_RW_FUNCS_64(ttbr1, TTBR1_64) 253 DEFINE_COPROCR_RW_FUNCS_64(cntvoff, CNTVOFF_64) 254 DEFINE_COPROCR_RW_FUNCS(csselr, CSSELR) 255 DEFINE_COPROCR_RW_FUNCS(hstr, HSTR) 256 DEFINE_COPROCR_RW_FUNCS(cnthp_ctl_el2, CNTHP_CTL) 257 DEFINE_COPROCR_RW_FUNCS(cnthp_tval_el2, CNTHP_TVAL) 258 DEFINE_COPROCR_RW_FUNCS_64(cnthp_cval_el2, CNTHP_CVAL_64) 259 260 #define get_cntp_ctl_enable(x) (((x) >> CNTP_CTL_ENABLE_SHIFT) & \ 261 CNTP_CTL_ENABLE_MASK) 262 #define get_cntp_ctl_imask(x) (((x) >> CNTP_CTL_IMASK_SHIFT) & \ 263 CNTP_CTL_IMASK_MASK) 264 #define get_cntp_ctl_istatus(x) (((x) >> CNTP_CTL_ISTATUS_SHIFT) & \ 265 CNTP_CTL_ISTATUS_MASK) 266 267 #define set_cntp_ctl_enable(x) ((x) |= U(1) << CNTP_CTL_ENABLE_SHIFT) 268 #define set_cntp_ctl_imask(x) ((x) |= U(1) << CNTP_CTL_IMASK_SHIFT) 269 270 #define clr_cntp_ctl_enable(x) ((x) &= ~(U(1) << CNTP_CTL_ENABLE_SHIFT)) 271 #define clr_cntp_ctl_imask(x) ((x) &= ~(U(1) << CNTP_CTL_IMASK_SHIFT)) 272 273 DEFINE_COPROCR_RW_FUNCS(icc_sre_el1, ICC_SRE) 274 DEFINE_COPROCR_RW_FUNCS(icc_sre_el2, ICC_HSRE) 275 DEFINE_COPROCR_RW_FUNCS(icc_sre_el3, ICC_MSRE) 276 DEFINE_COPROCR_RW_FUNCS(icc_pmr_el1, ICC_PMR) 277 DEFINE_COPROCR_RW_FUNCS(icc_rpr_el1, ICC_RPR) 278 DEFINE_COPROCR_RW_FUNCS(icc_igrpen1_el3, ICC_MGRPEN1) 279 DEFINE_COPROCR_RW_FUNCS(icc_igrpen1_el1, ICC_IGRPEN1) 280 DEFINE_COPROCR_RW_FUNCS(icc_igrpen0_el1, ICC_IGRPEN0) 281 DEFINE_COPROCR_RW_FUNCS(icc_hppir0_el1, ICC_HPPIR0) 282 DEFINE_COPROCR_RW_FUNCS(icc_hppir1_el1, ICC_HPPIR1) 283 DEFINE_COPROCR_RW_FUNCS(icc_iar0_el1, ICC_IAR0) 284 DEFINE_COPROCR_RW_FUNCS(icc_iar1_el1, ICC_IAR1) 285 DEFINE_COPROCR_RW_FUNCS(icc_eoir0_el1, ICC_EOIR0) 286 DEFINE_COPROCR_RW_FUNCS(icc_eoir1_el1, ICC_EOIR1) 287 DEFINE_COPROCR_RW_FUNCS_64(icc_sgi0r_el1, ICC_SGI0R_EL1_64) 288 DEFINE_COPROCR_WRITE_FUNC_64(icc_sgi1r, ICC_SGI1R_EL1_64) 289 DEFINE_COPROCR_WRITE_FUNC_64(icc_asgi1r, ICC_ASGI1R_EL1_64) 290 291 DEFINE_COPROCR_RW_FUNCS(sdcr, SDCR) 292 DEFINE_COPROCR_RW_FUNCS(hdcr, HDCR) 293 DEFINE_COPROCR_RW_FUNCS(cnthp_ctl, CNTHP_CTL) 294 DEFINE_COPROCR_RW_FUNCS(pmcr, PMCR) 295 296 /* 297 * Address translation 298 */ 299 DEFINE_COPROCR_WRITE_FUNC(ats1cpr, ATS1CPR) 300 DEFINE_COPROCR_WRITE_FUNC(ats1hr, ATS1HR) 301 DEFINE_COPROCR_RW_FUNCS_64(par, PAR_64) 302 303 DEFINE_COPROCR_RW_FUNCS(nsacr, NSACR) 304 305 /* AArch32 coproc registers for 32bit MMU descriptor support */ 306 DEFINE_COPROCR_RW_FUNCS(prrr, PRRR) 307 DEFINE_COPROCR_RW_FUNCS(nmrr, NMRR) 308 DEFINE_COPROCR_RW_FUNCS(dacr, DACR) 309 310 /* Coproc registers for 32bit AMU support */ 311 DEFINE_COPROCR_READ_FUNC(amcfgr, AMCFGR) 312 DEFINE_COPROCR_READ_FUNC(amcgcr, AMCGCR) 313 DEFINE_COPROCR_RW_FUNCS(amcr, AMCR) 314 315 DEFINE_COPROCR_RW_FUNCS(amcntenset0, AMCNTENSET0) 316 DEFINE_COPROCR_RW_FUNCS(amcntenset1, AMCNTENSET1) 317 DEFINE_COPROCR_RW_FUNCS(amcntenclr0, AMCNTENCLR0) 318 DEFINE_COPROCR_RW_FUNCS(amcntenclr1, AMCNTENCLR1) 319 320 /* Coproc registers for 64bit AMU support */ 321 DEFINE_COPROCR_RW_FUNCS_64(amevcntr00, AMEVCNTR00) 322 DEFINE_COPROCR_RW_FUNCS_64(amevcntr01, AMEVCNTR01) 323 DEFINE_COPROCR_RW_FUNCS_64(amevcntr02, AMEVCNTR02) 324 DEFINE_COPROCR_RW_FUNCS_64(amevcntr03, AMEVCNTR03) 325 326 /* 327 * TLBI operation prototypes 328 */ 329 DEFINE_TLBIOP_FUNC(all, TLBIALL) 330 DEFINE_TLBIOP_FUNC(allis, TLBIALLIS) 331 DEFINE_TLBIOP_PARAM_FUNC(mva, TLBIMVA) 332 DEFINE_TLBIOP_PARAM_FUNC(mvaa, TLBIMVAA) 333 DEFINE_TLBIOP_PARAM_FUNC(mvaais, TLBIMVAAIS) 334 DEFINE_TLBIOP_PARAM_FUNC(mvahis, TLBIMVAHIS) 335 336 /* 337 * BPI operation prototypes. 338 */ 339 DEFINE_BPIOP_FUNC(allis, BPIALLIS) 340 341 /* 342 * DC operation prototypes 343 */ 344 DEFINE_DCOP_PARAM_FUNC(civac, DCCIMVAC) 345 DEFINE_DCOP_PARAM_FUNC(ivac, DCIMVAC) 346 #if ERRATA_A53_819472 || ERRATA_A53_824069 || ERRATA_A53_827319 347 DEFINE_DCOP_PARAM_FUNC(cvac, DCCIMVAC) 348 #else 349 DEFINE_DCOP_PARAM_FUNC(cvac, DCCMVAC) 350 #endif 351 352 /* 353 * DynamIQ Shared Unit power management 354 */ 355 DEFINE_COPROCR_RW_FUNCS(clusterpwrdn, CLUSTERPWRDN) 356 357 /* 358 * RNDR is AArch64 only, so just provide a placeholder here to make the 359 * linker happy. 360 */ 361 static inline u_register_t read_rndr(void) 362 { 363 assert(1); 364 365 return 0; 366 } 367 368 /* Previously defined accessor functions with incomplete register names */ 369 #define dsb() dsbsy() 370 #define dmb() dmbsy() 371 372 /* dmb ld is not valid for armv7/thumb machines, so alias it to dmb */ 373 #if ARM_ARCH_MAJOR == 7 374 #define dmbld() dmb() 375 #endif 376 377 #define IS_IN_SECURE() \ 378 (GET_NS_BIT(read_scr()) == 0) 379 380 #define IS_IN_HYP() (GET_M32(read_cpsr()) == MODE32_hyp) 381 #define IS_IN_SVC() (GET_M32(read_cpsr()) == MODE32_svc) 382 #define IS_IN_MON() (GET_M32(read_cpsr()) == MODE32_mon) 383 #define IS_IN_EL2() IS_IN_HYP() 384 /* If EL3 is AArch32, then secure PL1 and monitor mode correspond to EL3 */ 385 #define IS_IN_EL3() \ 386 ((GET_M32(read_cpsr()) == MODE32_mon) || \ 387 (IS_IN_SECURE() && (GET_M32(read_cpsr()) != MODE32_usr))) 388 389 static inline unsigned int get_current_el(void) 390 { 391 if (IS_IN_EL3()) { 392 return 3U; 393 } else if (IS_IN_EL2()) { 394 return 2U; 395 } else { 396 return 1U; 397 } 398 } 399 400 /* Macros for compatibility with AArch64 system registers */ 401 #define read_mpidr_el1() read_mpidr() 402 403 #define read_scr_el3() read_scr() 404 #define write_scr_el3(_v) write_scr(_v) 405 406 #define read_hcr_el2() read_hcr() 407 #define write_hcr_el2(_v) write_hcr(_v) 408 409 #define read_cpacr_el1() read_cpacr() 410 #define write_cpacr_el1(_v) write_cpacr(_v) 411 412 #define read_cntfrq_el0() read_cntfrq() 413 #define write_cntfrq_el0(_v) write_cntfrq(_v) 414 #define read_isr_el1() read_isr() 415 416 #define read_cntpct_el0() read64_cntpct() 417 418 #define read_ctr_el0() read_ctr() 419 420 #define write_icc_sgi0r_el1(_v) write64_icc_sgi0r_el1(_v) 421 #define write_icc_sgi1r(_v) write64_icc_sgi1r(_v) 422 #define write_icc_asgi1r(_v) write64_icc_asgi1r(_v) 423 424 #define read_daif() read_cpsr() 425 #define write_daif(flags) write_cpsr(flags) 426 427 #define read_cnthp_cval_el2() read64_cnthp_cval_el2() 428 #define write_cnthp_cval_el2(v) write64_cnthp_cval_el2(v) 429 430 #define read_amcntenset0_el0() read_amcntenset0() 431 #define read_amcntenset1_el0() read_amcntenset1() 432 433 /* Helper functions to manipulate CPSR */ 434 static inline void enable_irq(void) 435 { 436 /* 437 * The compiler memory barrier will prevent the compiler from 438 * scheduling non-volatile memory access after the write to the 439 * register. 440 * 441 * This could happen if some initialization code issues non-volatile 442 * accesses to an area used by an interrupt handler, in the assumption 443 * that it is safe as the interrupts are disabled at the time it does 444 * that (according to program order). However, non-volatile accesses 445 * are not necessarily in program order relatively with volatile inline 446 * assembly statements (and volatile accesses). 447 */ 448 COMPILER_BARRIER(); 449 __asm__ volatile ("cpsie i"); 450 isb(); 451 } 452 453 static inline void enable_serror(void) 454 { 455 COMPILER_BARRIER(); 456 __asm__ volatile ("cpsie a"); 457 isb(); 458 } 459 460 static inline void enable_fiq(void) 461 { 462 COMPILER_BARRIER(); 463 __asm__ volatile ("cpsie f"); 464 isb(); 465 } 466 467 static inline void disable_irq(void) 468 { 469 COMPILER_BARRIER(); 470 __asm__ volatile ("cpsid i"); 471 isb(); 472 } 473 474 static inline void disable_serror(void) 475 { 476 COMPILER_BARRIER(); 477 __asm__ volatile ("cpsid a"); 478 isb(); 479 } 480 481 static inline void disable_fiq(void) 482 { 483 COMPILER_BARRIER(); 484 __asm__ volatile ("cpsid f"); 485 isb(); 486 } 487 488 #endif /* ARCH_HELPERS_H */ 489