1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (c) 2015, Linaro Limited 4 */ 5 #ifndef __LINUX_ARM_SMCCC_H 6 #define __LINUX_ARM_SMCCC_H 7 8 #include <linux/init.h> 9 #include <uapi/linux/const.h> 10 11 /* 12 * This file provides common defines for ARM SMC Calling Convention as 13 * specified in 14 * https://developer.arm.com/docs/den0028/latest 15 * 16 * This code is up-to-date with version DEN 0028 C 17 */ 18 19 #define ARM_SMCCC_STD_CALL _AC(0,U) 20 #define ARM_SMCCC_FAST_CALL _AC(1,U) 21 #define ARM_SMCCC_TYPE_SHIFT 31 22 23 #define ARM_SMCCC_SMC_32 0 24 #define ARM_SMCCC_SMC_64 1 25 #define ARM_SMCCC_CALL_CONV_SHIFT 30 26 27 #define ARM_SMCCC_OWNER_MASK 0x3F 28 #define ARM_SMCCC_OWNER_SHIFT 24 29 30 #define ARM_SMCCC_FUNC_MASK 0xFFFF 31 32 #define ARM_SMCCC_IS_FAST_CALL(smc_val) \ 33 ((smc_val) & (ARM_SMCCC_FAST_CALL << ARM_SMCCC_TYPE_SHIFT)) 34 #define ARM_SMCCC_IS_64(smc_val) \ 35 ((smc_val) & (ARM_SMCCC_SMC_64 << ARM_SMCCC_CALL_CONV_SHIFT)) 36 #define ARM_SMCCC_FUNC_NUM(smc_val) ((smc_val) & ARM_SMCCC_FUNC_MASK) 37 #define ARM_SMCCC_OWNER_NUM(smc_val) \ 38 (((smc_val) >> ARM_SMCCC_OWNER_SHIFT) & ARM_SMCCC_OWNER_MASK) 39 40 #define ARM_SMCCC_CALL_VAL(type, calling_convention, owner, func_num) \ 41 (((type) << ARM_SMCCC_TYPE_SHIFT) | \ 42 ((calling_convention) << ARM_SMCCC_CALL_CONV_SHIFT) | \ 43 (((owner) & ARM_SMCCC_OWNER_MASK) << ARM_SMCCC_OWNER_SHIFT) | \ 44 ((func_num) & ARM_SMCCC_FUNC_MASK)) 45 46 #define ARM_SMCCC_OWNER_ARCH 0 47 #define ARM_SMCCC_OWNER_CPU 1 48 #define ARM_SMCCC_OWNER_SIP 2 49 #define ARM_SMCCC_OWNER_OEM 3 50 #define ARM_SMCCC_OWNER_STANDARD 4 51 #define ARM_SMCCC_OWNER_STANDARD_HYP 5 52 #define ARM_SMCCC_OWNER_VENDOR_HYP 6 53 #define ARM_SMCCC_OWNER_TRUSTED_APP 48 54 #define ARM_SMCCC_OWNER_TRUSTED_APP_END 49 55 #define ARM_SMCCC_OWNER_TRUSTED_OS 50 56 #define ARM_SMCCC_OWNER_TRUSTED_OS_END 63 57 58 #define ARM_SMCCC_FUNC_QUERY_CALL_UID 0xff01 59 60 #define ARM_SMCCC_QUIRK_NONE 0 61 #define ARM_SMCCC_QUIRK_QCOM_A6 1 /* Save/restore register a6 */ 62 63 #define ARM_SMCCC_VERSION_1_0 0x10000 64 #define ARM_SMCCC_VERSION_1_1 0x10001 65 #define ARM_SMCCC_VERSION_1_2 0x10002 66 #define ARM_SMCCC_VERSION_1_3 0x10003 67 68 #define ARM_SMCCC_1_3_SVE_HINT 0x10000 69 70 #define ARM_SMCCC_VERSION_FUNC_ID \ 71 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 72 ARM_SMCCC_SMC_32, \ 73 0, 0) 74 75 #define ARM_SMCCC_ARCH_FEATURES_FUNC_ID \ 76 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 77 ARM_SMCCC_SMC_32, \ 78 0, 1) 79 80 #define ARM_SMCCC_ARCH_SOC_ID \ 81 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 82 ARM_SMCCC_SMC_32, \ 83 0, 2) 84 85 #define ARM_SMCCC_ARCH_WORKAROUND_1 \ 86 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 87 ARM_SMCCC_SMC_32, \ 88 0, 0x8000) 89 90 #define ARM_SMCCC_ARCH_WORKAROUND_2 \ 91 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 92 ARM_SMCCC_SMC_32, \ 93 0, 0x7fff) 94 95 #define ARM_SMCCC_ARCH_WORKAROUND_3 \ 96 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 97 ARM_SMCCC_SMC_32, \ 98 0, 0x3fff) 99 100 #define ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID \ 101 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 102 ARM_SMCCC_SMC_32, \ 103 ARM_SMCCC_OWNER_VENDOR_HYP, \ 104 ARM_SMCCC_FUNC_QUERY_CALL_UID) 105 106 /* KVM UID value: 28b46fb6-2ec5-11e9-a9ca-4b564d003a74 */ 107 #define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 0xb66fb428U 108 #define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 0xe911c52eU 109 #define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 0x564bcaa9U 110 #define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3 0x743a004dU 111 112 /* KVM "vendor specific" services */ 113 #define ARM_SMCCC_KVM_FUNC_FEATURES 0 114 #define ARM_SMCCC_KVM_FUNC_PTP 1 115 #define ARM_SMCCC_KVM_FUNC_FEATURES_2 127 116 #define ARM_SMCCC_KVM_NUM_FUNCS 128 117 118 #define ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID \ 119 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 120 ARM_SMCCC_SMC_32, \ 121 ARM_SMCCC_OWNER_VENDOR_HYP, \ 122 ARM_SMCCC_KVM_FUNC_FEATURES) 123 124 #define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1 125 126 /* 127 * ptp_kvm is a feature used for time sync between vm and host. 128 * ptp_kvm module in guest kernel will get service from host using 129 * this hypercall ID. 130 */ 131 #define ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID \ 132 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 133 ARM_SMCCC_SMC_32, \ 134 ARM_SMCCC_OWNER_VENDOR_HYP, \ 135 ARM_SMCCC_KVM_FUNC_PTP) 136 137 /* ptp_kvm counter type ID */ 138 #define KVM_PTP_VIRT_COUNTER 0 139 #define KVM_PTP_PHYS_COUNTER 1 140 141 /* Paravirtualised time calls (defined by ARM DEN0057A) */ 142 #define ARM_SMCCC_HV_PV_TIME_FEATURES \ 143 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 144 ARM_SMCCC_SMC_64, \ 145 ARM_SMCCC_OWNER_STANDARD_HYP, \ 146 0x20) 147 148 #define ARM_SMCCC_HV_PV_TIME_ST \ 149 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 150 ARM_SMCCC_SMC_64, \ 151 ARM_SMCCC_OWNER_STANDARD_HYP, \ 152 0x21) 153 154 /* TRNG entropy source calls (defined by ARM DEN0098) */ 155 #define ARM_SMCCC_TRNG_VERSION \ 156 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 157 ARM_SMCCC_SMC_32, \ 158 ARM_SMCCC_OWNER_STANDARD, \ 159 0x50) 160 161 #define ARM_SMCCC_TRNG_FEATURES \ 162 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 163 ARM_SMCCC_SMC_32, \ 164 ARM_SMCCC_OWNER_STANDARD, \ 165 0x51) 166 167 #define ARM_SMCCC_TRNG_GET_UUID \ 168 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 169 ARM_SMCCC_SMC_32, \ 170 ARM_SMCCC_OWNER_STANDARD, \ 171 0x52) 172 173 #define ARM_SMCCC_TRNG_RND32 \ 174 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 175 ARM_SMCCC_SMC_32, \ 176 ARM_SMCCC_OWNER_STANDARD, \ 177 0x53) 178 179 #define ARM_SMCCC_TRNG_RND64 \ 180 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 181 ARM_SMCCC_SMC_64, \ 182 ARM_SMCCC_OWNER_STANDARD, \ 183 0x53) 184 185 /* 186 * Return codes defined in ARM DEN 0070A 187 * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C 188 */ 189 #define SMCCC_RET_SUCCESS 0 190 #define SMCCC_RET_NOT_SUPPORTED -1 191 #define SMCCC_RET_NOT_REQUIRED -2 192 #define SMCCC_RET_INVALID_PARAMETER -3 193 194 #ifndef __ASSEMBLY__ 195 196 #include <linux/linkage.h> 197 #include <linux/types.h> 198 199 enum arm_smccc_conduit { 200 SMCCC_CONDUIT_NONE, 201 SMCCC_CONDUIT_SMC, 202 SMCCC_CONDUIT_HVC, 203 }; 204 205 /** 206 * arm_smccc_1_1_get_conduit() 207 * 208 * Returns the conduit to be used for SMCCCv1.1 or later. 209 * 210 * When SMCCCv1.1 is not present, returns SMCCC_CONDUIT_NONE. 211 */ 212 enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void); 213 214 /** 215 * arm_smccc_get_version() 216 * 217 * Returns the version to be used for SMCCCv1.1 or later. 218 * 219 * When SMCCCv1.1 or above is not present, returns SMCCCv1.0, but this 220 * does not imply the presence of firmware or a valid conduit. Caller 221 * handling SMCCCv1.0 must determine the conduit by other means. 222 */ 223 u32 arm_smccc_get_version(void); 224 225 void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit); 226 227 extern u64 smccc_has_sve_hint; 228 229 /** 230 * struct arm_smccc_res - Result from SMC/HVC call 231 * @a0-a3 result values from registers 0 to 3 232 */ 233 struct arm_smccc_res { 234 unsigned long a0; 235 unsigned long a1; 236 unsigned long a2; 237 unsigned long a3; 238 }; 239 240 #ifdef CONFIG_ARM64 241 /** 242 * struct arm_smccc_1_2_regs - Arguments for or Results from SMC/HVC call 243 * @a0-a17 argument values from registers 0 to 17 244 */ 245 struct arm_smccc_1_2_regs { 246 unsigned long a0; 247 unsigned long a1; 248 unsigned long a2; 249 unsigned long a3; 250 unsigned long a4; 251 unsigned long a5; 252 unsigned long a6; 253 unsigned long a7; 254 unsigned long a8; 255 unsigned long a9; 256 unsigned long a10; 257 unsigned long a11; 258 unsigned long a12; 259 unsigned long a13; 260 unsigned long a14; 261 unsigned long a15; 262 unsigned long a16; 263 unsigned long a17; 264 }; 265 266 /** 267 * arm_smccc_1_2_hvc() - make HVC calls 268 * @args: arguments passed via struct arm_smccc_1_2_regs 269 * @res: result values via struct arm_smccc_1_2_regs 270 * 271 * This function is used to make HVC calls following SMC Calling Convention 272 * v1.2 or above. The content of the supplied param are copied from the 273 * structure to registers prior to the HVC instruction. The return values 274 * are updated with the content from registers on return from the HVC 275 * instruction. 276 */ 277 asmlinkage void arm_smccc_1_2_hvc(const struct arm_smccc_1_2_regs *args, 278 struct arm_smccc_1_2_regs *res); 279 280 /** 281 * arm_smccc_1_2_smc() - make SMC calls 282 * @args: arguments passed via struct arm_smccc_1_2_regs 283 * @res: result values via struct arm_smccc_1_2_regs 284 * 285 * This function is used to make SMC calls following SMC Calling Convention 286 * v1.2 or above. The content of the supplied param are copied from the 287 * structure to registers prior to the SMC instruction. The return values 288 * are updated with the content from registers on return from the SMC 289 * instruction. 290 */ 291 asmlinkage void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args, 292 struct arm_smccc_1_2_regs *res); 293 #endif 294 295 /** 296 * struct arm_smccc_quirk - Contains quirk information 297 * @id: quirk identification 298 * @state: quirk specific information 299 * @a6: Qualcomm quirk entry for returning post-smc call contents of a6 300 */ 301 struct arm_smccc_quirk { 302 int id; 303 union { 304 unsigned long a6; 305 } state; 306 }; 307 308 /** 309 * __arm_smccc_sve_check() - Set the SVE hint bit when doing SMC calls 310 * 311 * Sets the SMCCC hint bit to indicate if there is live state in the SVE 312 * registers, this modifies x0 in place and should never be called from C 313 * code. 314 */ 315 asmlinkage unsigned long __arm_smccc_sve_check(unsigned long x0); 316 317 /** 318 * __arm_smccc_smc() - make SMC calls 319 * @a0-a7: arguments passed in registers 0 to 7 320 * @res: result values from registers 0 to 3 321 * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required. 322 * 323 * This function is used to make SMC calls following SMC Calling Convention. 324 * The content of the supplied param are copied to registers 0 to 7 prior 325 * to the SMC instruction. The return values are updated with the content 326 * from register 0 to 3 on return from the SMC instruction. An optional 327 * quirk structure provides vendor specific behavior. 328 */ 329 #ifdef CONFIG_HAVE_ARM_SMCCC 330 asmlinkage void __arm_smccc_smc(unsigned long a0, unsigned long a1, 331 unsigned long a2, unsigned long a3, unsigned long a4, 332 unsigned long a5, unsigned long a6, unsigned long a7, 333 struct arm_smccc_res *res, struct arm_smccc_quirk *quirk); 334 #else 335 static inline void __arm_smccc_smc(unsigned long a0, unsigned long a1, 336 unsigned long a2, unsigned long a3, unsigned long a4, 337 unsigned long a5, unsigned long a6, unsigned long a7, 338 struct arm_smccc_res *res, struct arm_smccc_quirk *quirk) 339 { 340 *res = (struct arm_smccc_res){}; 341 } 342 #endif 343 344 /** 345 * __arm_smccc_hvc() - make HVC calls 346 * @a0-a7: arguments passed in registers 0 to 7 347 * @res: result values from registers 0 to 3 348 * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required. 349 * 350 * This function is used to make HVC calls following SMC Calling 351 * Convention. The content of the supplied param are copied to registers 0 352 * to 7 prior to the HVC instruction. The return values are updated with 353 * the content from register 0 to 3 on return from the HVC instruction. An 354 * optional quirk structure provides vendor specific behavior. 355 */ 356 asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1, 357 unsigned long a2, unsigned long a3, unsigned long a4, 358 unsigned long a5, unsigned long a6, unsigned long a7, 359 struct arm_smccc_res *res, struct arm_smccc_quirk *quirk); 360 361 #define arm_smccc_smc(...) __arm_smccc_smc(__VA_ARGS__, NULL) 362 363 #define arm_smccc_smc_quirk(...) __arm_smccc_smc(__VA_ARGS__) 364 365 #define arm_smccc_hvc(...) __arm_smccc_hvc(__VA_ARGS__, NULL) 366 367 #define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__) 368 369 /* SMCCC v1.1 implementation madness follows */ 370 #ifdef CONFIG_ARM64 371 372 #define SMCCC_SMC_INST "smc #0" 373 #define SMCCC_HVC_INST "hvc #0" 374 375 #elif defined(CONFIG_ARM) 376 #include <asm/opcodes-sec.h> 377 #include <asm/opcodes-virt.h> 378 379 #define SMCCC_SMC_INST __SMC(0) 380 #define SMCCC_HVC_INST __HVC(0) 381 382 #endif 383 384 /* nVHE hypervisor doesn't have a current thread so needs separate checks */ 385 #if defined(CONFIG_ARM64_SVE) && !defined(__KVM_NVHE_HYPERVISOR__) 386 387 #define SMCCC_SVE_CHECK ALTERNATIVE("nop \n", "bl __arm_smccc_sve_check \n", \ 388 ARM64_SVE) 389 #define smccc_sve_clobbers "x16", "x30", "cc", 390 391 #else 392 393 #define SMCCC_SVE_CHECK 394 #define smccc_sve_clobbers 395 396 #endif 397 398 #define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x 399 400 #define __count_args(...) \ 401 ___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0) 402 403 #define __constraint_read_0 "r" (arg0) 404 #define __constraint_read_1 __constraint_read_0, "r" (arg1) 405 #define __constraint_read_2 __constraint_read_1, "r" (arg2) 406 #define __constraint_read_3 __constraint_read_2, "r" (arg3) 407 #define __constraint_read_4 __constraint_read_3, "r" (arg4) 408 #define __constraint_read_5 __constraint_read_4, "r" (arg5) 409 #define __constraint_read_6 __constraint_read_5, "r" (arg6) 410 #define __constraint_read_7 __constraint_read_6, "r" (arg7) 411 412 #define __declare_arg_0(a0, res) \ 413 struct arm_smccc_res *___res = res; \ 414 register unsigned long arg0 asm("r0") = (u32)a0 415 416 #define __declare_arg_1(a0, a1, res) \ 417 typeof(a1) __a1 = a1; \ 418 struct arm_smccc_res *___res = res; \ 419 register unsigned long arg0 asm("r0") = (u32)a0; \ 420 register typeof(a1) arg1 asm("r1") = __a1 421 422 #define __declare_arg_2(a0, a1, a2, res) \ 423 typeof(a1) __a1 = a1; \ 424 typeof(a2) __a2 = a2; \ 425 struct arm_smccc_res *___res = res; \ 426 register unsigned long arg0 asm("r0") = (u32)a0; \ 427 register typeof(a1) arg1 asm("r1") = __a1; \ 428 register typeof(a2) arg2 asm("r2") = __a2 429 430 #define __declare_arg_3(a0, a1, a2, a3, res) \ 431 typeof(a1) __a1 = a1; \ 432 typeof(a2) __a2 = a2; \ 433 typeof(a3) __a3 = a3; \ 434 struct arm_smccc_res *___res = res; \ 435 register unsigned long arg0 asm("r0") = (u32)a0; \ 436 register typeof(a1) arg1 asm("r1") = __a1; \ 437 register typeof(a2) arg2 asm("r2") = __a2; \ 438 register typeof(a3) arg3 asm("r3") = __a3 439 440 #define __declare_arg_4(a0, a1, a2, a3, a4, res) \ 441 typeof(a4) __a4 = a4; \ 442 __declare_arg_3(a0, a1, a2, a3, res); \ 443 register typeof(a4) arg4 asm("r4") = __a4 444 445 #define __declare_arg_5(a0, a1, a2, a3, a4, a5, res) \ 446 typeof(a5) __a5 = a5; \ 447 __declare_arg_4(a0, a1, a2, a3, a4, res); \ 448 register typeof(a5) arg5 asm("r5") = __a5 449 450 #define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res) \ 451 typeof(a6) __a6 = a6; \ 452 __declare_arg_5(a0, a1, a2, a3, a4, a5, res); \ 453 register typeof(a6) arg6 asm("r6") = __a6 454 455 #define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res) \ 456 typeof(a7) __a7 = a7; \ 457 __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res); \ 458 register typeof(a7) arg7 asm("r7") = __a7 459 460 #define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__) 461 #define __declare_args(count, ...) ___declare_args(count, __VA_ARGS__) 462 463 #define ___constraints(count) \ 464 : __constraint_read_ ## count \ 465 : smccc_sve_clobbers "memory" 466 #define __constraints(count) ___constraints(count) 467 468 /* 469 * We have an output list that is not necessarily used, and GCC feels 470 * entitled to optimise the whole sequence away. "volatile" is what 471 * makes it stick. 472 */ 473 #define __arm_smccc_1_1(inst, ...) \ 474 do { \ 475 register unsigned long r0 asm("r0"); \ 476 register unsigned long r1 asm("r1"); \ 477 register unsigned long r2 asm("r2"); \ 478 register unsigned long r3 asm("r3"); \ 479 __declare_args(__count_args(__VA_ARGS__), __VA_ARGS__); \ 480 asm volatile(SMCCC_SVE_CHECK \ 481 inst "\n" : \ 482 "=r" (r0), "=r" (r1), "=r" (r2), "=r" (r3) \ 483 __constraints(__count_args(__VA_ARGS__))); \ 484 if (___res) \ 485 *___res = (typeof(*___res)){r0, r1, r2, r3}; \ 486 } while (0) 487 488 /* 489 * arm_smccc_1_1_smc() - make an SMCCC v1.1 compliant SMC call 490 * 491 * This is a variadic macro taking one to eight source arguments, and 492 * an optional return structure. 493 * 494 * @a0-a7: arguments passed in registers 0 to 7 495 * @res: result values from registers 0 to 3 496 * 497 * This macro is used to make SMC calls following SMC Calling Convention v1.1. 498 * The content of the supplied param are copied to registers 0 to 7 prior 499 * to the SMC instruction. The return values are updated with the content 500 * from register 0 to 3 on return from the SMC instruction if not NULL. 501 */ 502 #define arm_smccc_1_1_smc(...) __arm_smccc_1_1(SMCCC_SMC_INST, __VA_ARGS__) 503 504 /* 505 * arm_smccc_1_1_hvc() - make an SMCCC v1.1 compliant HVC call 506 * 507 * This is a variadic macro taking one to eight source arguments, and 508 * an optional return structure. 509 * 510 * @a0-a7: arguments passed in registers 0 to 7 511 * @res: result values from registers 0 to 3 512 * 513 * This macro is used to make HVC calls following SMC Calling Convention v1.1. 514 * The content of the supplied param are copied to registers 0 to 7 prior 515 * to the HVC instruction. The return values are updated with the content 516 * from register 0 to 3 on return from the HVC instruction if not NULL. 517 */ 518 #define arm_smccc_1_1_hvc(...) __arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__) 519 520 /* 521 * Like arm_smccc_1_1* but always returns SMCCC_RET_NOT_SUPPORTED. 522 * Used when the SMCCC conduit is not defined. The empty asm statement 523 * avoids compiler warnings about unused variables. 524 */ 525 #define __fail_smccc_1_1(...) \ 526 do { \ 527 __declare_args(__count_args(__VA_ARGS__), __VA_ARGS__); \ 528 asm ("" : __constraints(__count_args(__VA_ARGS__))); \ 529 if (___res) \ 530 ___res->a0 = SMCCC_RET_NOT_SUPPORTED; \ 531 } while (0) 532 533 /* 534 * arm_smccc_1_1_invoke() - make an SMCCC v1.1 compliant call 535 * 536 * This is a variadic macro taking one to eight source arguments, and 537 * an optional return structure. 538 * 539 * @a0-a7: arguments passed in registers 0 to 7 540 * @res: result values from registers 0 to 3 541 * 542 * This macro will make either an HVC call or an SMC call depending on the 543 * current SMCCC conduit. If no valid conduit is available then -1 544 * (SMCCC_RET_NOT_SUPPORTED) is returned in @res.a0 (if supplied). 545 * 546 * The return value also provides the conduit that was used. 547 */ 548 #define arm_smccc_1_1_invoke(...) ({ \ 549 int method = arm_smccc_1_1_get_conduit(); \ 550 switch (method) { \ 551 case SMCCC_CONDUIT_HVC: \ 552 arm_smccc_1_1_hvc(__VA_ARGS__); \ 553 break; \ 554 case SMCCC_CONDUIT_SMC: \ 555 arm_smccc_1_1_smc(__VA_ARGS__); \ 556 break; \ 557 default: \ 558 __fail_smccc_1_1(__VA_ARGS__); \ 559 method = SMCCC_CONDUIT_NONE; \ 560 break; \ 561 } \ 562 method; \ 563 }) 564 565 #endif /*__ASSEMBLY__*/ 566 #endif /*__LINUX_ARM_SMCCC_H*/ 567