1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * SBI initialilization and all extension implementation. 4 * 5 * Copyright (c) 2020 Western Digital Corporation or its affiliates. 6 */ 7 8#include <linux/bits.h> 9#include <linux/init.h> 10#include <linux/mm.h> 11#include <linux/pm.h> 12#include <linux/reboot.h> 13#include <asm/sbi.h> 14#include <asm/smp.h> 15#include <asm/tlbflush.h> 16 17/* default SBI version is 0.1 */ 18unsigned long sbi_spec_version __ro_after_init = SBI_SPEC_VERSION_DEFAULT; 19EXPORT_SYMBOL(sbi_spec_version); 20 21static void (*__sbi_set_timer)(uint64_t stime) __ro_after_init; 22static void (*__sbi_send_ipi)(unsigned int cpu) __ro_after_init; 23static int (*__sbi_rfence)(int fid, const struct cpumask *cpu_mask, 24 unsigned long start, unsigned long size, 25 unsigned long arg4, unsigned long arg5) __ro_after_init; 26 27struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, 28 unsigned long arg1, unsigned long arg2, 29 unsigned long arg3, unsigned long arg4, 30 unsigned long arg5) 31{ 32 struct sbiret ret; 33 34 register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0); 35 register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1); 36 register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2); 37 register uintptr_t a3 asm ("a3") = (uintptr_t)(arg3); 38 register uintptr_t a4 asm ("a4") = (uintptr_t)(arg4); 39 register uintptr_t a5 asm ("a5") = (uintptr_t)(arg5); 40 register uintptr_t a6 asm ("a6") = (uintptr_t)(fid); 41 register uintptr_t a7 asm ("a7") = (uintptr_t)(ext); 42 asm volatile ("ecall" 43 : "+r" (a0), "+r" (a1) 44 : "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7) 45 : "memory"); 46 ret.error = a0; 47 ret.value = a1; 48 49 return ret; 50} 51EXPORT_SYMBOL(sbi_ecall); 52 53int sbi_err_map_linux_errno(int err) 54{ 55 switch (err) { 56 case SBI_SUCCESS: 57 return 0; 58 case SBI_ERR_DENIED: 59 return -EPERM; 60 case SBI_ERR_INVALID_PARAM: 61 return -EINVAL; 62 case SBI_ERR_INVALID_ADDRESS: 63 return -EFAULT; 64 case SBI_ERR_NOT_SUPPORTED: 65 case SBI_ERR_FAILURE: 66 default: 67 return -ENOTSUPP; 68 }; 69} 70EXPORT_SYMBOL(sbi_err_map_linux_errno); 71 72#ifdef CONFIG_RISCV_SBI_V01 73static unsigned long __sbi_v01_cpumask_to_hartmask(const struct cpumask *cpu_mask) 74{ 75 unsigned long cpuid, hartid; 76 unsigned long hmask = 0; 77 78 /* 79 * There is no maximum hartid concept in RISC-V and NR_CPUS must not be 80 * associated with hartid. As SBI v0.1 is only kept for backward compatibility 81 * and will be removed in the future, there is no point in supporting hartid 82 * greater than BITS_PER_LONG (32 for RV32 and 64 for RV64). Ideally, SBI v0.2 83 * should be used for platforms with hartid greater than BITS_PER_LONG. 84 */ 85 for_each_cpu(cpuid, cpu_mask) { 86 hartid = cpuid_to_hartid_map(cpuid); 87 if (hartid >= BITS_PER_LONG) { 88 pr_warn("Unable to send any request to hartid > BITS_PER_LONG for SBI v0.1\n"); 89 break; 90 } 91 hmask |= BIT(hartid); 92 } 93 94 return hmask; 95} 96 97/** 98 * sbi_console_putchar() - Writes given character to the console device. 99 * @ch: The data to be written to the console. 100 * 101 * Return: None 102 */ 103void sbi_console_putchar(int ch) 104{ 105 sbi_ecall(SBI_EXT_0_1_CONSOLE_PUTCHAR, 0, ch, 0, 0, 0, 0, 0); 106} 107EXPORT_SYMBOL(sbi_console_putchar); 108 109/** 110 * sbi_console_getchar() - Reads a byte from console device. 111 * 112 * Returns the value read from console. 113 */ 114int sbi_console_getchar(void) 115{ 116 struct sbiret ret; 117 118 ret = sbi_ecall(SBI_EXT_0_1_CONSOLE_GETCHAR, 0, 0, 0, 0, 0, 0, 0); 119 120 return ret.error; 121} 122EXPORT_SYMBOL(sbi_console_getchar); 123 124/** 125 * sbi_shutdown() - Remove all the harts from executing supervisor code. 126 * 127 * Return: None 128 */ 129void sbi_shutdown(void) 130{ 131 sbi_ecall(SBI_EXT_0_1_SHUTDOWN, 0, 0, 0, 0, 0, 0, 0); 132} 133EXPORT_SYMBOL(sbi_shutdown); 134 135/** 136 * __sbi_set_timer_v01() - Program the timer for next timer event. 137 * @stime_value: The value after which next timer event should fire. 138 * 139 * Return: None 140 */ 141static void __sbi_set_timer_v01(uint64_t stime_value) 142{ 143#if __riscv_xlen == 32 144 sbi_ecall(SBI_EXT_0_1_SET_TIMER, 0, stime_value, 145 stime_value >> 32, 0, 0, 0, 0); 146#else 147 sbi_ecall(SBI_EXT_0_1_SET_TIMER, 0, stime_value, 0, 0, 0, 0, 0); 148#endif 149} 150 151static void __sbi_send_ipi_v01(unsigned int cpu) 152{ 153 unsigned long hart_mask = 154 __sbi_v01_cpumask_to_hartmask(cpumask_of(cpu)); 155 sbi_ecall(SBI_EXT_0_1_SEND_IPI, 0, (unsigned long)(&hart_mask), 156 0, 0, 0, 0, 0); 157} 158 159static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_mask, 160 unsigned long start, unsigned long size, 161 unsigned long arg4, unsigned long arg5) 162{ 163 int result = 0; 164 unsigned long hart_mask; 165 166 if (!cpu_mask || cpumask_empty(cpu_mask)) 167 cpu_mask = cpu_online_mask; 168 hart_mask = __sbi_v01_cpumask_to_hartmask(cpu_mask); 169 170 /* v0.2 function IDs are equivalent to v0.1 extension IDs */ 171 switch (fid) { 172 case SBI_EXT_RFENCE_REMOTE_FENCE_I: 173 sbi_ecall(SBI_EXT_0_1_REMOTE_FENCE_I, 0, 174 (unsigned long)&hart_mask, 0, 0, 0, 0, 0); 175 break; 176 case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA: 177 sbi_ecall(SBI_EXT_0_1_REMOTE_SFENCE_VMA, 0, 178 (unsigned long)&hart_mask, start, size, 179 0, 0, 0); 180 break; 181 case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID: 182 sbi_ecall(SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID, 0, 183 (unsigned long)&hart_mask, start, size, 184 arg4, 0, 0); 185 break; 186 default: 187 pr_err("SBI call [%d]not supported in SBI v0.1\n", fid); 188 result = -EINVAL; 189 } 190 191 return result; 192} 193 194static void sbi_set_power_off(void) 195{ 196 pm_power_off = sbi_shutdown; 197} 198#else 199static void __sbi_set_timer_v01(uint64_t stime_value) 200{ 201 pr_warn("Timer extension is not available in SBI v%lu.%lu\n", 202 sbi_major_version(), sbi_minor_version()); 203} 204 205static void __sbi_send_ipi_v01(unsigned int cpu) 206{ 207 pr_warn("IPI extension is not available in SBI v%lu.%lu\n", 208 sbi_major_version(), sbi_minor_version()); 209} 210 211static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_mask, 212 unsigned long start, unsigned long size, 213 unsigned long arg4, unsigned long arg5) 214{ 215 pr_warn("remote fence extension is not available in SBI v%lu.%lu\n", 216 sbi_major_version(), sbi_minor_version()); 217 218 return 0; 219} 220 221static void sbi_set_power_off(void) {} 222#endif /* CONFIG_RISCV_SBI_V01 */ 223 224static void __sbi_set_timer_v02(uint64_t stime_value) 225{ 226#if __riscv_xlen == 32 227 sbi_ecall(SBI_EXT_TIME, SBI_EXT_TIME_SET_TIMER, stime_value, 228 stime_value >> 32, 0, 0, 0, 0); 229#else 230 sbi_ecall(SBI_EXT_TIME, SBI_EXT_TIME_SET_TIMER, stime_value, 0, 231 0, 0, 0, 0); 232#endif 233} 234 235static void __sbi_send_ipi_v02(unsigned int cpu) 236{ 237 int result; 238 struct sbiret ret = {0}; 239 240 ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI, 241 1UL, cpuid_to_hartid_map(cpu), 0, 0, 0, 0); 242 if (ret.error) { 243 result = sbi_err_map_linux_errno(ret.error); 244 pr_err("%s: hbase = [%lu] failed (error [%d])\n", 245 __func__, cpuid_to_hartid_map(cpu), result); 246 } 247} 248 249static int __sbi_rfence_v02_call(unsigned long fid, unsigned long hmask, 250 unsigned long hbase, unsigned long start, 251 unsigned long size, unsigned long arg4, 252 unsigned long arg5) 253{ 254 struct sbiret ret = {0}; 255 int ext = SBI_EXT_RFENCE; 256 int result = 0; 257 258 switch (fid) { 259 case SBI_EXT_RFENCE_REMOTE_FENCE_I: 260 ret = sbi_ecall(ext, fid, hmask, hbase, 0, 0, 0, 0); 261 break; 262 case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA: 263 ret = sbi_ecall(ext, fid, hmask, hbase, start, 264 size, 0, 0); 265 break; 266 case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID: 267 ret = sbi_ecall(ext, fid, hmask, hbase, start, 268 size, arg4, 0); 269 break; 270 271 case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA: 272 ret = sbi_ecall(ext, fid, hmask, hbase, start, 273 size, 0, 0); 274 break; 275 case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID: 276 ret = sbi_ecall(ext, fid, hmask, hbase, start, 277 size, arg4, 0); 278 break; 279 case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA: 280 ret = sbi_ecall(ext, fid, hmask, hbase, start, 281 size, 0, 0); 282 break; 283 case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID: 284 ret = sbi_ecall(ext, fid, hmask, hbase, start, 285 size, arg4, 0); 286 break; 287 default: 288 pr_err("unknown function ID [%lu] for SBI extension [%d]\n", 289 fid, ext); 290 result = -EINVAL; 291 } 292 293 if (ret.error) { 294 result = sbi_err_map_linux_errno(ret.error); 295 pr_err("%s: hbase = [%lu] hmask = [0x%lx] failed (error [%d])\n", 296 __func__, hbase, hmask, result); 297 } 298 299 return result; 300} 301 302static int __sbi_rfence_v02(int fid, const struct cpumask *cpu_mask, 303 unsigned long start, unsigned long size, 304 unsigned long arg4, unsigned long arg5) 305{ 306 unsigned long hartid, cpuid, hmask = 0, hbase = 0, htop = 0; 307 int result; 308 309 if (!cpu_mask || cpumask_empty(cpu_mask)) 310 cpu_mask = cpu_online_mask; 311 312 for_each_cpu(cpuid, cpu_mask) { 313 hartid = cpuid_to_hartid_map(cpuid); 314 if (hmask) { 315 if (hartid + BITS_PER_LONG <= htop || 316 hbase + BITS_PER_LONG <= hartid) { 317 result = __sbi_rfence_v02_call(fid, hmask, 318 hbase, start, size, arg4, arg5); 319 if (result) 320 return result; 321 hmask = 0; 322 } else if (hartid < hbase) { 323 /* shift the mask to fit lower hartid */ 324 hmask <<= hbase - hartid; 325 hbase = hartid; 326 } 327 } 328 if (!hmask) { 329 hbase = hartid; 330 htop = hartid; 331 } else if (hartid > htop) { 332 htop = hartid; 333 } 334 hmask |= BIT(hartid - hbase); 335 } 336 337 if (hmask) { 338 result = __sbi_rfence_v02_call(fid, hmask, hbase, 339 start, size, arg4, arg5); 340 if (result) 341 return result; 342 } 343 344 return 0; 345} 346 347/** 348 * sbi_set_timer() - Program the timer for next timer event. 349 * @stime_value: The value after which next timer event should fire. 350 * 351 * Return: None. 352 */ 353void sbi_set_timer(uint64_t stime_value) 354{ 355 __sbi_set_timer(stime_value); 356} 357 358/** 359 * sbi_send_ipi() - Send an IPI to any hart. 360 * @cpu: Logical id of the target CPU. 361 */ 362void sbi_send_ipi(unsigned int cpu) 363{ 364 __sbi_send_ipi(cpu); 365} 366EXPORT_SYMBOL(sbi_send_ipi); 367 368/** 369 * sbi_remote_fence_i() - Execute FENCE.I instruction on given remote harts. 370 * @cpu_mask: A cpu mask containing all the target harts. 371 * 372 * Return: 0 on success, appropriate linux error code otherwise. 373 */ 374int sbi_remote_fence_i(const struct cpumask *cpu_mask) 375{ 376 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_FENCE_I, 377 cpu_mask, 0, 0, 0, 0); 378} 379EXPORT_SYMBOL(sbi_remote_fence_i); 380 381/** 382 * sbi_remote_sfence_vma_asid() - Execute SFENCE.VMA instructions on given 383 * remote harts for a virtual address range belonging to a specific ASID or not. 384 * 385 * @cpu_mask: A cpu mask containing all the target harts. 386 * @start: Start of the virtual address 387 * @size: Total size of the virtual address range. 388 * @asid: The value of address space identifier (ASID), or FLUSH_TLB_NO_ASID 389 * for flushing all address spaces. 390 * 391 * Return: 0 on success, appropriate linux error code otherwise. 392 */ 393int sbi_remote_sfence_vma_asid(const struct cpumask *cpu_mask, 394 unsigned long start, 395 unsigned long size, 396 unsigned long asid) 397{ 398 if (asid == FLUSH_TLB_NO_ASID) 399 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA, 400 cpu_mask, start, size, 0, 0); 401 else 402 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID, 403 cpu_mask, start, size, asid, 0); 404} 405EXPORT_SYMBOL(sbi_remote_sfence_vma_asid); 406 407/** 408 * sbi_remote_hfence_gvma() - Execute HFENCE.GVMA instructions on given remote 409 * harts for the specified guest physical address range. 410 * @cpu_mask: A cpu mask containing all the target harts. 411 * @start: Start of the guest physical address 412 * @size: Total size of the guest physical address range. 413 * 414 * Return: None 415 */ 416int sbi_remote_hfence_gvma(const struct cpumask *cpu_mask, 417 unsigned long start, 418 unsigned long size) 419{ 420 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA, 421 cpu_mask, start, size, 0, 0); 422} 423EXPORT_SYMBOL_GPL(sbi_remote_hfence_gvma); 424 425/** 426 * sbi_remote_hfence_gvma_vmid() - Execute HFENCE.GVMA instructions on given 427 * remote harts for a guest physical address range belonging to a specific VMID. 428 * 429 * @cpu_mask: A cpu mask containing all the target harts. 430 * @start: Start of the guest physical address 431 * @size: Total size of the guest physical address range. 432 * @vmid: The value of guest ID (VMID). 433 * 434 * Return: 0 if success, Error otherwise. 435 */ 436int sbi_remote_hfence_gvma_vmid(const struct cpumask *cpu_mask, 437 unsigned long start, 438 unsigned long size, 439 unsigned long vmid) 440{ 441 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID, 442 cpu_mask, start, size, vmid, 0); 443} 444EXPORT_SYMBOL(sbi_remote_hfence_gvma_vmid); 445 446/** 447 * sbi_remote_hfence_vvma() - Execute HFENCE.VVMA instructions on given remote 448 * harts for the current guest virtual address range. 449 * @cpu_mask: A cpu mask containing all the target harts. 450 * @start: Start of the current guest virtual address 451 * @size: Total size of the current guest virtual address range. 452 * 453 * Return: None 454 */ 455int sbi_remote_hfence_vvma(const struct cpumask *cpu_mask, 456 unsigned long start, 457 unsigned long size) 458{ 459 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA, 460 cpu_mask, start, size, 0, 0); 461} 462EXPORT_SYMBOL(sbi_remote_hfence_vvma); 463 464/** 465 * sbi_remote_hfence_vvma_asid() - Execute HFENCE.VVMA instructions on given 466 * remote harts for current guest virtual address range belonging to a specific 467 * ASID. 468 * 469 * @cpu_mask: A cpu mask containing all the target harts. 470 * @start: Start of the current guest virtual address 471 * @size: Total size of the current guest virtual address range. 472 * @asid: The value of address space identifier (ASID). 473 * 474 * Return: None 475 */ 476int sbi_remote_hfence_vvma_asid(const struct cpumask *cpu_mask, 477 unsigned long start, 478 unsigned long size, 479 unsigned long asid) 480{ 481 return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID, 482 cpu_mask, start, size, asid, 0); 483} 484EXPORT_SYMBOL(sbi_remote_hfence_vvma_asid); 485 486static void sbi_srst_reset(unsigned long type, unsigned long reason) 487{ 488 sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason, 489 0, 0, 0, 0); 490 pr_warn("%s: type=0x%lx reason=0x%lx failed\n", 491 __func__, type, reason); 492} 493 494static int sbi_srst_reboot(struct notifier_block *this, 495 unsigned long mode, void *cmd) 496{ 497 sbi_srst_reset((mode == REBOOT_WARM || mode == REBOOT_SOFT) ? 498 SBI_SRST_RESET_TYPE_WARM_REBOOT : 499 SBI_SRST_RESET_TYPE_COLD_REBOOT, 500 SBI_SRST_RESET_REASON_NONE); 501 return NOTIFY_DONE; 502} 503 504static struct notifier_block sbi_srst_reboot_nb; 505 506static void sbi_srst_power_off(void) 507{ 508 sbi_srst_reset(SBI_SRST_RESET_TYPE_SHUTDOWN, 509 SBI_SRST_RESET_REASON_NONE); 510} 511 512/** 513 * sbi_probe_extension() - Check if an SBI extension ID is supported or not. 514 * @extid: The extension ID to be probed. 515 * 516 * Return: 1 or an extension specific nonzero value if yes, 0 otherwise. 517 */ 518long sbi_probe_extension(int extid) 519{ 520 struct sbiret ret; 521 522 ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid, 523 0, 0, 0, 0, 0); 524 if (!ret.error) 525 return ret.value; 526 527 return 0; 528} 529EXPORT_SYMBOL(sbi_probe_extension); 530 531static long __sbi_base_ecall(int fid) 532{ 533 struct sbiret ret; 534 535 ret = sbi_ecall(SBI_EXT_BASE, fid, 0, 0, 0, 0, 0, 0); 536 if (!ret.error) 537 return ret.value; 538 else 539 return sbi_err_map_linux_errno(ret.error); 540} 541 542static inline long sbi_get_spec_version(void) 543{ 544 return __sbi_base_ecall(SBI_EXT_BASE_GET_SPEC_VERSION); 545} 546 547static inline long sbi_get_firmware_id(void) 548{ 549 return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_ID); 550} 551 552static inline long sbi_get_firmware_version(void) 553{ 554 return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_VERSION); 555} 556 557long sbi_get_mvendorid(void) 558{ 559 return __sbi_base_ecall(SBI_EXT_BASE_GET_MVENDORID); 560} 561EXPORT_SYMBOL_GPL(sbi_get_mvendorid); 562 563long sbi_get_marchid(void) 564{ 565 return __sbi_base_ecall(SBI_EXT_BASE_GET_MARCHID); 566} 567EXPORT_SYMBOL_GPL(sbi_get_marchid); 568 569long sbi_get_mimpid(void) 570{ 571 return __sbi_base_ecall(SBI_EXT_BASE_GET_MIMPID); 572} 573EXPORT_SYMBOL_GPL(sbi_get_mimpid); 574 575bool sbi_debug_console_available; 576 577int sbi_debug_console_write(const char *bytes, unsigned int num_bytes) 578{ 579 phys_addr_t base_addr; 580 struct sbiret ret; 581 582 if (!sbi_debug_console_available) 583 return -EOPNOTSUPP; 584 585 if (is_vmalloc_addr(bytes)) 586 base_addr = page_to_phys(vmalloc_to_page(bytes)) + 587 offset_in_page(bytes); 588 else 589 base_addr = __pa(bytes); 590 if (PAGE_SIZE < (offset_in_page(bytes) + num_bytes)) 591 num_bytes = PAGE_SIZE - offset_in_page(bytes); 592 593 if (IS_ENABLED(CONFIG_32BIT)) 594 ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE, 595 num_bytes, lower_32_bits(base_addr), 596 upper_32_bits(base_addr), 0, 0, 0); 597 else 598 ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE, 599 num_bytes, base_addr, 0, 0, 0, 0); 600 601 if (ret.error == SBI_ERR_FAILURE) 602 return -EIO; 603 return ret.error ? sbi_err_map_linux_errno(ret.error) : ret.value; 604} 605 606int sbi_debug_console_read(char *bytes, unsigned int num_bytes) 607{ 608 phys_addr_t base_addr; 609 struct sbiret ret; 610 611 if (!sbi_debug_console_available) 612 return -EOPNOTSUPP; 613 614 if (is_vmalloc_addr(bytes)) 615 base_addr = page_to_phys(vmalloc_to_page(bytes)) + 616 offset_in_page(bytes); 617 else 618 base_addr = __pa(bytes); 619 if (PAGE_SIZE < (offset_in_page(bytes) + num_bytes)) 620 num_bytes = PAGE_SIZE - offset_in_page(bytes); 621 622 if (IS_ENABLED(CONFIG_32BIT)) 623 ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ, 624 num_bytes, lower_32_bits(base_addr), 625 upper_32_bits(base_addr), 0, 0, 0); 626 else 627 ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ, 628 num_bytes, base_addr, 0, 0, 0, 0); 629 630 if (ret.error == SBI_ERR_FAILURE) 631 return -EIO; 632 return ret.error ? sbi_err_map_linux_errno(ret.error) : ret.value; 633} 634 635void __init sbi_init(void) 636{ 637 int ret; 638 639 sbi_set_power_off(); 640 ret = sbi_get_spec_version(); 641 if (ret > 0) 642 sbi_spec_version = ret; 643 644 pr_info("SBI specification v%lu.%lu detected\n", 645 sbi_major_version(), sbi_minor_version()); 646 647 if (!sbi_spec_is_0_1()) { 648 pr_info("SBI implementation ID=0x%lx Version=0x%lx\n", 649 sbi_get_firmware_id(), sbi_get_firmware_version()); 650 if (sbi_probe_extension(SBI_EXT_TIME)) { 651 __sbi_set_timer = __sbi_set_timer_v02; 652 pr_info("SBI TIME extension detected\n"); 653 } else { 654 __sbi_set_timer = __sbi_set_timer_v01; 655 } 656 if (sbi_probe_extension(SBI_EXT_IPI)) { 657 __sbi_send_ipi = __sbi_send_ipi_v02; 658 pr_info("SBI IPI extension detected\n"); 659 } else { 660 __sbi_send_ipi = __sbi_send_ipi_v01; 661 } 662 if (sbi_probe_extension(SBI_EXT_RFENCE)) { 663 __sbi_rfence = __sbi_rfence_v02; 664 pr_info("SBI RFENCE extension detected\n"); 665 } else { 666 __sbi_rfence = __sbi_rfence_v01; 667 } 668 if ((sbi_spec_version >= sbi_mk_version(0, 3)) && 669 sbi_probe_extension(SBI_EXT_SRST)) { 670 pr_info("SBI SRST extension detected\n"); 671 pm_power_off = sbi_srst_power_off; 672 sbi_srst_reboot_nb.notifier_call = sbi_srst_reboot; 673 sbi_srst_reboot_nb.priority = 192; 674 register_restart_handler(&sbi_srst_reboot_nb); 675 } 676 if ((sbi_spec_version >= sbi_mk_version(2, 0)) && 677 (sbi_probe_extension(SBI_EXT_DBCN) > 0)) { 678 pr_info("SBI DBCN extension detected\n"); 679 sbi_debug_console_available = true; 680 } 681 } else { 682 __sbi_set_timer = __sbi_set_timer_v01; 683 __sbi_send_ipi = __sbi_send_ipi_v01; 684 __sbi_rfence = __sbi_rfence_v01; 685 } 686} 687