1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Firmware-Assisted Dump support on POWER platform (OPAL). 4 * 5 * Copyright 2019, Hari Bathini, IBM Corporation. 6 */ 7 8 #define pr_fmt(fmt) "opal fadump: " fmt 9 10 #include <linux/string.h> 11 #include <linux/seq_file.h> 12 #include <linux/of.h> 13 #include <linux/of_fdt.h> 14 #include <linux/libfdt.h> 15 #include <linux/mm.h> 16 #include <linux/crash_dump.h> 17 18 #include <asm/page.h> 19 #include <asm/opal.h> 20 #include <asm/fadump-internal.h> 21 22 #include "opal-fadump.h" 23 24 25 #ifdef CONFIG_PRESERVE_FA_DUMP 26 /* 27 * When dump is active but PRESERVE_FA_DUMP is enabled on the kernel, 28 * ensure crash data is preserved in hope that the subsequent memory 29 * preserving kernel boot is going to process this crash data. 30 */ 31 void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 32 { 33 const struct opal_fadump_mem_struct *opal_fdm_active; 34 const __be32 *prop; 35 unsigned long dn; 36 u64 addr = 0; 37 s64 ret; 38 39 dn = of_get_flat_dt_subnode_by_name(node, "dump"); 40 if (dn == -FDT_ERR_NOTFOUND) 41 return; 42 43 /* 44 * Check if dump has been initiated on last reboot. 45 */ 46 prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL); 47 if (!prop) 48 return; 49 50 ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr); 51 if ((ret != OPAL_SUCCESS) || !addr) { 52 pr_debug("Could not get Kernel metadata (%lld)\n", ret); 53 return; 54 } 55 56 /* 57 * Preserve memory only if kernel memory regions are registered 58 * with f/w for MPIPL. 59 */ 60 addr = be64_to_cpu(addr); 61 pr_debug("Kernel metadata addr: %llx\n", addr); 62 opal_fdm_active = (void *)addr; 63 if (be16_to_cpu(opal_fdm_active->registered_regions) == 0) 64 return; 65 66 ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_BOOT_MEM, &addr); 67 if ((ret != OPAL_SUCCESS) || !addr) { 68 pr_err("Failed to get boot memory tag (%lld)\n", ret); 69 return; 70 } 71 72 /* 73 * Memory below this address can be used for booting a 74 * capture kernel or petitboot kernel. Preserve everything 75 * above this address for processing crashdump. 76 */ 77 fadump_conf->boot_mem_top = be64_to_cpu(addr); 78 pr_debug("Preserve everything above %llx\n", fadump_conf->boot_mem_top); 79 80 pr_info("Firmware-assisted dump is active.\n"); 81 fadump_conf->dump_active = 1; 82 } 83 84 #else /* CONFIG_PRESERVE_FA_DUMP */ 85 static const struct opal_fadump_mem_struct *opal_fdm_active; 86 static const struct opal_mpipl_fadump *opal_cpu_metadata; 87 static struct opal_fadump_mem_struct *opal_fdm; 88 89 #ifdef CONFIG_OPAL_CORE 90 extern bool kernel_initiated; 91 #endif 92 93 static int opal_fadump_unregister(struct fw_dump *fadump_conf); 94 95 static void opal_fadump_update_config(struct fw_dump *fadump_conf, 96 const struct opal_fadump_mem_struct *fdm) 97 { 98 pr_debug("Boot memory regions count: %d\n", be16_to_cpu(fdm->region_cnt)); 99 100 /* 101 * The destination address of the first boot memory region is the 102 * destination address of boot memory regions. 103 */ 104 fadump_conf->boot_mem_dest_addr = be64_to_cpu(fdm->rgn[0].dest); 105 pr_debug("Destination address of boot memory regions: %#016llx\n", 106 fadump_conf->boot_mem_dest_addr); 107 108 fadump_conf->fadumphdr_addr = be64_to_cpu(fdm->fadumphdr_addr); 109 } 110 111 /* 112 * This function is called in the capture kernel to get configuration details 113 * from metadata setup by the first kernel. 114 */ 115 static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 116 const struct opal_fadump_mem_struct *fdm) 117 { 118 unsigned long base, size, last_end, hole_size; 119 int i; 120 121 if (!fadump_conf->dump_active) 122 return; 123 124 last_end = 0; 125 hole_size = 0; 126 fadump_conf->boot_memory_size = 0; 127 128 pr_debug("Boot memory regions:\n"); 129 for (i = 0; i < be16_to_cpu(fdm->region_cnt); i++) { 130 base = be64_to_cpu(fdm->rgn[i].src); 131 size = be64_to_cpu(fdm->rgn[i].size); 132 pr_debug("\t[%03d] base: 0x%lx, size: 0x%lx\n", i, base, size); 133 134 fadump_conf->boot_mem_addr[i] = base; 135 fadump_conf->boot_mem_sz[i] = size; 136 fadump_conf->boot_memory_size += size; 137 hole_size += (base - last_end); 138 139 last_end = base + size; 140 } 141 142 /* 143 * Start address of reserve dump area (permanent reservation) for 144 * re-registering FADump after dump capture. 145 */ 146 fadump_conf->reserve_dump_area_start = be64_to_cpu(fdm->rgn[0].dest); 147 148 /* 149 * Rarely, but it can so happen that system crashes before all 150 * boot memory regions are registered for MPIPL. In such 151 * cases, warn that the vmcore may not be accurate and proceed 152 * anyway as that is the best bet considering free pages, cache 153 * pages, user pages, etc are usually filtered out. 154 * 155 * Hope the memory that could not be preserved only has pages 156 * that are usually filtered out while saving the vmcore. 157 */ 158 if (be16_to_cpu(fdm->region_cnt) > be16_to_cpu(fdm->registered_regions)) { 159 pr_warn("Not all memory regions were saved!!!\n"); 160 pr_warn(" Unsaved memory regions:\n"); 161 i = be16_to_cpu(fdm->registered_regions); 162 while (i < be16_to_cpu(fdm->region_cnt)) { 163 pr_warn("\t[%03d] base: 0x%llx, size: 0x%llx\n", 164 i, be64_to_cpu(fdm->rgn[i].src), 165 be64_to_cpu(fdm->rgn[i].size)); 166 i++; 167 } 168 169 pr_warn("If the unsaved regions only contain pages that are filtered out (eg. free/user pages), the vmcore should still be usable.\n"); 170 pr_warn("WARNING: If the unsaved regions contain kernel pages, the vmcore will be corrupted.\n"); 171 } 172 173 fadump_conf->boot_mem_top = (fadump_conf->boot_memory_size + hole_size); 174 fadump_conf->boot_mem_regs_cnt = be16_to_cpu(fdm->region_cnt); 175 opal_fadump_update_config(fadump_conf, fdm); 176 } 177 178 /* Initialize kernel metadata */ 179 static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm) 180 { 181 fdm->version = OPAL_FADUMP_VERSION; 182 fdm->region_cnt = cpu_to_be16(0); 183 fdm->registered_regions = cpu_to_be16(0); 184 fdm->fadumphdr_addr = cpu_to_be64(0); 185 } 186 187 static u64 opal_fadump_init_mem_struct(struct fw_dump *fadump_conf) 188 { 189 u64 addr = fadump_conf->reserve_dump_area_start; 190 u16 reg_cnt; 191 int i; 192 193 opal_fdm = __va(fadump_conf->kernel_metadata); 194 opal_fadump_init_metadata(opal_fdm); 195 196 /* Boot memory regions */ 197 reg_cnt = be16_to_cpu(opal_fdm->region_cnt); 198 for (i = 0; i < fadump_conf->boot_mem_regs_cnt; i++) { 199 opal_fdm->rgn[i].src = cpu_to_be64(fadump_conf->boot_mem_addr[i]); 200 opal_fdm->rgn[i].dest = cpu_to_be64(addr); 201 opal_fdm->rgn[i].size = cpu_to_be64(fadump_conf->boot_mem_sz[i]); 202 203 reg_cnt++; 204 addr += fadump_conf->boot_mem_sz[i]; 205 } 206 opal_fdm->region_cnt = cpu_to_be16(reg_cnt); 207 208 /* 209 * Kernel metadata is passed to f/w and retrieved in capture kernel. 210 * So, use it to save fadump header address instead of calculating it. 211 */ 212 opal_fdm->fadumphdr_addr = cpu_to_be64(be64_to_cpu(opal_fdm->rgn[0].dest) + 213 fadump_conf->boot_memory_size); 214 215 opal_fadump_update_config(fadump_conf, opal_fdm); 216 217 return addr; 218 } 219 220 static u64 opal_fadump_get_metadata_size(void) 221 { 222 return PAGE_ALIGN(sizeof(struct opal_fadump_mem_struct)); 223 } 224 225 static int opal_fadump_setup_metadata(struct fw_dump *fadump_conf) 226 { 227 int err = 0; 228 s64 ret; 229 230 /* 231 * Use the last page(s) in FADump memory reservation for 232 * kernel metadata. 233 */ 234 fadump_conf->kernel_metadata = (fadump_conf->reserve_dump_area_start + 235 fadump_conf->reserve_dump_area_size - 236 opal_fadump_get_metadata_size()); 237 pr_info("Kernel metadata addr: %llx\n", fadump_conf->kernel_metadata); 238 239 /* Initialize kernel metadata before registering the address with f/w */ 240 opal_fdm = __va(fadump_conf->kernel_metadata); 241 opal_fadump_init_metadata(opal_fdm); 242 243 /* 244 * Register metadata address with f/w. Can be retrieved in 245 * the capture kernel. 246 */ 247 ret = opal_mpipl_register_tag(OPAL_MPIPL_TAG_KERNEL, 248 fadump_conf->kernel_metadata); 249 if (ret != OPAL_SUCCESS) { 250 pr_err("Failed to set kernel metadata tag!\n"); 251 err = -EPERM; 252 } 253 254 /* 255 * Register boot memory top address with f/w. Should be retrieved 256 * by a kernel that intends to preserve crash'ed kernel's memory. 257 */ 258 ret = opal_mpipl_register_tag(OPAL_MPIPL_TAG_BOOT_MEM, 259 fadump_conf->boot_mem_top); 260 if (ret != OPAL_SUCCESS) { 261 pr_err("Failed to set boot memory tag!\n"); 262 err = -EPERM; 263 } 264 265 return err; 266 } 267 268 static u64 opal_fadump_get_bootmem_min(void) 269 { 270 return OPAL_FADUMP_MIN_BOOT_MEM; 271 } 272 273 static int opal_fadump_register(struct fw_dump *fadump_conf) 274 { 275 s64 rc = OPAL_PARAMETER; 276 u16 registered_regs; 277 int i, err = -EIO; 278 279 registered_regs = be16_to_cpu(opal_fdm->registered_regions); 280 for (i = 0; i < be16_to_cpu(opal_fdm->region_cnt); i++) { 281 rc = opal_mpipl_update(OPAL_MPIPL_ADD_RANGE, 282 be64_to_cpu(opal_fdm->rgn[i].src), 283 be64_to_cpu(opal_fdm->rgn[i].dest), 284 be64_to_cpu(opal_fdm->rgn[i].size)); 285 if (rc != OPAL_SUCCESS) 286 break; 287 288 registered_regs++; 289 } 290 opal_fdm->registered_regions = cpu_to_be16(registered_regs); 291 292 switch (rc) { 293 case OPAL_SUCCESS: 294 pr_info("Registration is successful!\n"); 295 fadump_conf->dump_registered = 1; 296 err = 0; 297 break; 298 case OPAL_RESOURCE: 299 /* If MAX regions limit in f/w is hit, warn and proceed. */ 300 pr_warn("%d regions could not be registered for MPIPL as MAX limit is reached!\n", 301 (be16_to_cpu(opal_fdm->region_cnt) - 302 be16_to_cpu(opal_fdm->registered_regions))); 303 fadump_conf->dump_registered = 1; 304 err = 0; 305 break; 306 case OPAL_PARAMETER: 307 pr_err("Failed to register. Parameter Error(%lld).\n", rc); 308 break; 309 case OPAL_HARDWARE: 310 pr_err("Support not available.\n"); 311 fadump_conf->fadump_supported = 0; 312 fadump_conf->fadump_enabled = 0; 313 break; 314 default: 315 pr_err("Failed to register. Unknown Error(%lld).\n", rc); 316 break; 317 } 318 319 /* 320 * If some regions were registered before OPAL_MPIPL_ADD_RANGE 321 * OPAL call failed, unregister all regions. 322 */ 323 if ((err < 0) && (be16_to_cpu(opal_fdm->registered_regions) > 0)) 324 opal_fadump_unregister(fadump_conf); 325 326 return err; 327 } 328 329 static int opal_fadump_unregister(struct fw_dump *fadump_conf) 330 { 331 s64 rc; 332 333 rc = opal_mpipl_update(OPAL_MPIPL_REMOVE_ALL, 0, 0, 0); 334 if (rc) { 335 pr_err("Failed to un-register - unexpected Error(%lld).\n", rc); 336 return -EIO; 337 } 338 339 opal_fdm->registered_regions = cpu_to_be16(0); 340 fadump_conf->dump_registered = 0; 341 return 0; 342 } 343 344 static int opal_fadump_invalidate(struct fw_dump *fadump_conf) 345 { 346 s64 rc; 347 348 rc = opal_mpipl_update(OPAL_MPIPL_FREE_PRESERVED_MEMORY, 0, 0, 0); 349 if (rc) { 350 pr_err("Failed to invalidate - unexpected Error(%lld).\n", rc); 351 return -EIO; 352 } 353 354 fadump_conf->dump_active = 0; 355 opal_fdm_active = NULL; 356 return 0; 357 } 358 359 static void opal_fadump_cleanup(struct fw_dump *fadump_conf) 360 { 361 s64 ret; 362 363 ret = opal_mpipl_register_tag(OPAL_MPIPL_TAG_KERNEL, 0); 364 if (ret != OPAL_SUCCESS) 365 pr_warn("Could not reset (%llu) kernel metadata tag!\n", ret); 366 } 367 368 /* 369 * Verify if CPU state data is available. If available, do a bit of sanity 370 * checking before processing this data. 371 */ 372 static bool __init is_opal_fadump_cpu_data_valid(struct fw_dump *fadump_conf) 373 { 374 if (!opal_cpu_metadata) 375 return false; 376 377 fadump_conf->cpu_state_data_version = 378 be32_to_cpu(opal_cpu_metadata->cpu_data_version); 379 fadump_conf->cpu_state_entry_size = 380 be32_to_cpu(opal_cpu_metadata->cpu_data_size); 381 fadump_conf->cpu_state_dest_vaddr = 382 (u64)__va(be64_to_cpu(opal_cpu_metadata->region[0].dest)); 383 fadump_conf->cpu_state_data_size = 384 be64_to_cpu(opal_cpu_metadata->region[0].size); 385 386 if (fadump_conf->cpu_state_data_version != HDAT_FADUMP_CPU_DATA_VER) { 387 pr_warn("Supported CPU state data version: %u, found: %d!\n", 388 HDAT_FADUMP_CPU_DATA_VER, 389 fadump_conf->cpu_state_data_version); 390 pr_warn("WARNING: F/W using newer CPU state data format!!\n"); 391 } 392 393 if ((fadump_conf->cpu_state_dest_vaddr == 0) || 394 (fadump_conf->cpu_state_entry_size == 0) || 395 (fadump_conf->cpu_state_entry_size > 396 fadump_conf->cpu_state_data_size)) { 397 pr_err("CPU state data is invalid. Ignoring!\n"); 398 return false; 399 } 400 401 return true; 402 } 403 404 /* 405 * Convert CPU state data saved at the time of crash into ELF notes. 406 * 407 * While the crashing CPU's register data is saved by the kernel, CPU state 408 * data for all CPUs is saved by f/w. In CPU state data provided by f/w, 409 * each register entry is of 16 bytes, a numerical identifier along with 410 * a GPR/SPR flag in the first 8 bytes and the register value in the next 411 * 8 bytes. For more details refer to F/W documentation. If this data is 412 * missing or in unsupported format, append crashing CPU's register data 413 * saved by the kernel in the PT_NOTE, to have something to work with in 414 * the vmcore file. 415 */ 416 static int __init 417 opal_fadump_build_cpu_notes(struct fw_dump *fadump_conf, 418 struct fadump_crash_info_header *fdh) 419 { 420 u32 thread_pir, size_per_thread, regs_offset, regs_cnt, reg_esize; 421 struct hdat_fadump_thread_hdr *thdr; 422 bool is_cpu_data_valid = false; 423 u32 num_cpus = 1, *note_buf; 424 struct pt_regs regs; 425 char *bufp; 426 int rc, i; 427 428 if (is_opal_fadump_cpu_data_valid(fadump_conf)) { 429 size_per_thread = fadump_conf->cpu_state_entry_size; 430 num_cpus = (fadump_conf->cpu_state_data_size / size_per_thread); 431 bufp = __va(fadump_conf->cpu_state_dest_vaddr); 432 is_cpu_data_valid = true; 433 } 434 435 rc = fadump_setup_cpu_notes_buf(num_cpus); 436 if (rc != 0) 437 return rc; 438 439 note_buf = (u32 *)fadump_conf->cpu_notes_buf_vaddr; 440 if (!is_cpu_data_valid) 441 goto out; 442 443 /* 444 * Offset for register entries, entry size and registers count is 445 * duplicated in every thread header in keeping with HDAT format. 446 * Use these values from the first thread header. 447 */ 448 thdr = (struct hdat_fadump_thread_hdr *)bufp; 449 regs_offset = (offsetof(struct hdat_fadump_thread_hdr, offset) + 450 be32_to_cpu(thdr->offset)); 451 reg_esize = be32_to_cpu(thdr->esize); 452 regs_cnt = be32_to_cpu(thdr->ecnt); 453 454 pr_debug("--------CPU State Data------------\n"); 455 pr_debug("NumCpus : %u\n", num_cpus); 456 pr_debug("\tOffset: %u, Entry size: %u, Cnt: %u\n", 457 regs_offset, reg_esize, regs_cnt); 458 459 for (i = 0; i < num_cpus; i++, bufp += size_per_thread) { 460 thdr = (struct hdat_fadump_thread_hdr *)bufp; 461 462 thread_pir = be32_to_cpu(thdr->pir); 463 pr_debug("[%04d] PIR: 0x%x, core state: 0x%02x\n", 464 i, thread_pir, thdr->core_state); 465 466 /* 467 * If this is kernel initiated crash, crashing_cpu would be set 468 * appropriately and register data of the crashing CPU saved by 469 * crashing kernel. Add this saved register data of crashing CPU 470 * to elf notes and populate the pt_regs for the remaining CPUs 471 * from register state data provided by firmware. 472 */ 473 if (fdh->crashing_cpu == thread_pir) { 474 note_buf = fadump_regs_to_elf_notes(note_buf, 475 &fdh->regs); 476 pr_debug("Crashing CPU PIR: 0x%x - R1 : 0x%lx, NIP : 0x%lx\n", 477 fdh->crashing_cpu, fdh->regs.gpr[1], 478 fdh->regs.nip); 479 continue; 480 } 481 482 /* 483 * Register state data of MAX cores is provided by firmware, 484 * but some of this cores may not be active. So, while 485 * processing register state data, check core state and 486 * skip threads that belong to inactive cores. 487 */ 488 if (thdr->core_state == HDAT_FADUMP_CORE_INACTIVE) 489 continue; 490 491 opal_fadump_read_regs((bufp + regs_offset), regs_cnt, 492 reg_esize, true, ®s); 493 note_buf = fadump_regs_to_elf_notes(note_buf, ®s); 494 pr_debug("CPU PIR: 0x%x - R1 : 0x%lx, NIP : 0x%lx\n", 495 thread_pir, regs.gpr[1], regs.nip); 496 } 497 498 out: 499 /* 500 * CPU state data is invalid/unsupported. Try appending crashing CPU's 501 * register data, if it is saved by the kernel. 502 */ 503 if (fadump_conf->cpu_notes_buf_vaddr == (u64)note_buf) { 504 if (fdh->crashing_cpu == FADUMP_CPU_UNKNOWN) { 505 fadump_free_cpu_notes_buf(); 506 return -ENODEV; 507 } 508 509 pr_warn("WARNING: appending only crashing CPU's register data\n"); 510 note_buf = fadump_regs_to_elf_notes(note_buf, &(fdh->regs)); 511 } 512 513 final_note(note_buf); 514 515 pr_debug("Updating elfcore header (%llx) with cpu notes\n", 516 fdh->elfcorehdr_addr); 517 fadump_update_elfcore_header(__va(fdh->elfcorehdr_addr)); 518 return 0; 519 } 520 521 static int __init opal_fadump_process(struct fw_dump *fadump_conf) 522 { 523 struct fadump_crash_info_header *fdh; 524 int rc = -EINVAL; 525 526 if (!opal_fdm_active || !fadump_conf->fadumphdr_addr) 527 return rc; 528 529 /* Validate the fadump crash info header */ 530 fdh = __va(fadump_conf->fadumphdr_addr); 531 if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { 532 pr_err("Crash info header is not valid.\n"); 533 return rc; 534 } 535 536 #ifdef CONFIG_OPAL_CORE 537 /* 538 * If this is a kernel initiated crash, crashing_cpu would be set 539 * appropriately and register data of the crashing CPU saved by 540 * crashing kernel. Add this saved register data of crashing CPU 541 * to elf notes and populate the pt_regs for the remaining CPUs 542 * from register state data provided by firmware. 543 */ 544 if (fdh->crashing_cpu != FADUMP_CPU_UNKNOWN) 545 kernel_initiated = true; 546 #endif 547 548 rc = opal_fadump_build_cpu_notes(fadump_conf, fdh); 549 if (rc) 550 return rc; 551 552 /* 553 * We are done validating dump info and elfcore header is now ready 554 * to be exported. set elfcorehdr_addr so that vmcore module will 555 * export the elfcore header through '/proc/vmcore'. 556 */ 557 elfcorehdr_addr = fdh->elfcorehdr_addr; 558 559 return rc; 560 } 561 562 static void opal_fadump_region_show(struct fw_dump *fadump_conf, 563 struct seq_file *m) 564 { 565 const struct opal_fadump_mem_struct *fdm_ptr; 566 u64 dumped_bytes = 0; 567 int i; 568 569 if (fadump_conf->dump_active) 570 fdm_ptr = opal_fdm_active; 571 else 572 fdm_ptr = opal_fdm; 573 574 for (i = 0; i < be16_to_cpu(fdm_ptr->region_cnt); i++) { 575 /* 576 * Only regions that are registered for MPIPL 577 * would have dump data. 578 */ 579 if ((fadump_conf->dump_active) && 580 (i < be16_to_cpu(fdm_ptr->registered_regions))) 581 dumped_bytes = be64_to_cpu(fdm_ptr->rgn[i].size); 582 583 seq_printf(m, "DUMP: Src: %#016llx, Dest: %#016llx, ", 584 be64_to_cpu(fdm_ptr->rgn[i].src), 585 be64_to_cpu(fdm_ptr->rgn[i].dest)); 586 seq_printf(m, "Size: %#llx, Dumped: %#llx bytes\n", 587 be64_to_cpu(fdm_ptr->rgn[i].size), dumped_bytes); 588 } 589 590 /* Dump is active. Show preserved area start address. */ 591 if (fadump_conf->dump_active) { 592 seq_printf(m, "\nMemory above %#016llx is reserved for saving crash dump\n", 593 fadump_conf->boot_mem_top); 594 } 595 } 596 597 static void opal_fadump_trigger(struct fadump_crash_info_header *fdh, 598 const char *msg) 599 { 600 int rc; 601 602 /* 603 * Unlike on pSeries platform, logical CPU number is not provided 604 * with architected register state data. So, store the crashing 605 * CPU's PIR instead to plug the appropriate register data for 606 * crashing CPU in the vmcore file. 607 */ 608 fdh->crashing_cpu = (u32)mfspr(SPRN_PIR); 609 610 rc = opal_cec_reboot2(OPAL_REBOOT_MPIPL, msg); 611 if (rc == OPAL_UNSUPPORTED) { 612 pr_emerg("Reboot type %d not supported.\n", 613 OPAL_REBOOT_MPIPL); 614 } else if (rc == OPAL_HARDWARE) 615 pr_emerg("No backend support for MPIPL!\n"); 616 } 617 618 static struct fadump_ops opal_fadump_ops = { 619 .fadump_init_mem_struct = opal_fadump_init_mem_struct, 620 .fadump_get_metadata_size = opal_fadump_get_metadata_size, 621 .fadump_setup_metadata = opal_fadump_setup_metadata, 622 .fadump_get_bootmem_min = opal_fadump_get_bootmem_min, 623 .fadump_register = opal_fadump_register, 624 .fadump_unregister = opal_fadump_unregister, 625 .fadump_invalidate = opal_fadump_invalidate, 626 .fadump_cleanup = opal_fadump_cleanup, 627 .fadump_process = opal_fadump_process, 628 .fadump_region_show = opal_fadump_region_show, 629 .fadump_trigger = opal_fadump_trigger, 630 }; 631 632 void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 633 { 634 const __be32 *prop; 635 unsigned long dn; 636 __be64 be_addr; 637 u64 addr = 0; 638 int i, len; 639 s64 ret; 640 641 /* 642 * Check if Firmware-Assisted Dump is supported. if yes, check 643 * if dump has been initiated on last reboot. 644 */ 645 dn = of_get_flat_dt_subnode_by_name(node, "dump"); 646 if (dn == -FDT_ERR_NOTFOUND) { 647 pr_debug("FADump support is missing!\n"); 648 return; 649 } 650 651 if (!of_flat_dt_is_compatible(dn, "ibm,opal-dump")) { 652 pr_err("Support missing for this f/w version!\n"); 653 return; 654 } 655 656 prop = of_get_flat_dt_prop(dn, "fw-load-area", &len); 657 if (prop) { 658 /* 659 * Each f/w load area is an (address,size) pair, 660 * 2 cells each, totalling 4 cells per range. 661 */ 662 for (i = 0; i < len / (sizeof(*prop) * 4); i++) { 663 u64 base, end; 664 665 base = of_read_number(prop + (i * 4) + 0, 2); 666 end = base; 667 end += of_read_number(prop + (i * 4) + 2, 2); 668 if (end > OPAL_FADUMP_MIN_BOOT_MEM) { 669 pr_err("F/W load area: 0x%llx-0x%llx\n", 670 base, end); 671 pr_err("F/W version not supported!\n"); 672 return; 673 } 674 } 675 } 676 677 fadump_conf->ops = &opal_fadump_ops; 678 fadump_conf->fadump_supported = 1; 679 680 /* 681 * Firmware supports 32-bit field for size. Align it to PAGE_SIZE 682 * and request firmware to copy multiple kernel boot memory regions. 683 */ 684 fadump_conf->max_copy_size = ALIGN_DOWN(U32_MAX, PAGE_SIZE); 685 686 /* 687 * Check if dump has been initiated on last reboot. 688 */ 689 prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL); 690 if (!prop) 691 return; 692 693 ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &be_addr); 694 if ((ret != OPAL_SUCCESS) || !be_addr) { 695 pr_err("Failed to get Kernel metadata (%lld)\n", ret); 696 return; 697 } 698 699 addr = be64_to_cpu(be_addr); 700 pr_debug("Kernel metadata addr: %llx\n", addr); 701 702 opal_fdm_active = __va(addr); 703 if (opal_fdm_active->version != OPAL_FADUMP_VERSION) { 704 pr_warn("Supported kernel metadata version: %u, found: %d!\n", 705 OPAL_FADUMP_VERSION, opal_fdm_active->version); 706 pr_warn("WARNING: Kernel metadata format mismatch identified! Core file maybe corrupted..\n"); 707 } 708 709 /* Kernel regions not registered with f/w for MPIPL */ 710 if (be16_to_cpu(opal_fdm_active->registered_regions) == 0) { 711 opal_fdm_active = NULL; 712 return; 713 } 714 715 ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_CPU, &be_addr); 716 if (be_addr) { 717 addr = be64_to_cpu(be_addr); 718 pr_debug("CPU metadata addr: %llx\n", addr); 719 opal_cpu_metadata = __va(addr); 720 } 721 722 pr_info("Firmware-assisted dump is active.\n"); 723 fadump_conf->dump_active = 1; 724 opal_fadump_get_config(fadump_conf, opal_fdm_active); 725 } 726 #endif /* !CONFIG_PRESERVE_FA_DUMP */ 727