1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * acpi_numa.c - ACPI NUMA support 4 * 5 * Copyright (C) 2002 Takayoshi Kochi <t-kochi@bq.jp.nec.com> 6 */ 7 8 #define pr_fmt(fmt) "ACPI: " fmt 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/types.h> 14 #include <linux/errno.h> 15 #include <linux/acpi.h> 16 #include <linux/memblock.h> 17 #include <linux/numa.h> 18 #include <linux/nodemask.h> 19 #include <linux/topology.h> 20 #include <linux/numa_memblks.h> 21 22 static nodemask_t nodes_found_map = NODE_MASK_NONE; 23 24 /* maps to convert between proximity domain and logical node ID */ 25 static int pxm_to_node_map[MAX_PXM_DOMAINS] 26 = { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE }; 27 static int node_to_pxm_map[MAX_NUMNODES] 28 = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; 29 30 unsigned char acpi_srat_revision __initdata; 31 static int acpi_numa __initdata; 32 33 static int last_real_pxm; 34 35 void __init disable_srat(void) 36 { 37 acpi_numa = -1; 38 } 39 40 int pxm_to_node(int pxm) 41 { 42 if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off) 43 return NUMA_NO_NODE; 44 return pxm_to_node_map[pxm]; 45 } 46 EXPORT_SYMBOL(pxm_to_node); 47 48 int node_to_pxm(int node) 49 { 50 if (node < 0) 51 return PXM_INVAL; 52 return node_to_pxm_map[node]; 53 } 54 55 static void __acpi_map_pxm_to_node(int pxm, int node) 56 { 57 if (pxm_to_node_map[pxm] == NUMA_NO_NODE || node < pxm_to_node_map[pxm]) 58 pxm_to_node_map[pxm] = node; 59 if (node_to_pxm_map[node] == PXM_INVAL || pxm < node_to_pxm_map[node]) 60 node_to_pxm_map[node] = pxm; 61 } 62 63 int acpi_map_pxm_to_node(int pxm) 64 { 65 int node; 66 67 if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off) 68 return NUMA_NO_NODE; 69 70 node = pxm_to_node_map[pxm]; 71 72 if (node == NUMA_NO_NODE) { 73 node = first_unset_node(nodes_found_map); 74 if (node >= MAX_NUMNODES) 75 return NUMA_NO_NODE; 76 __acpi_map_pxm_to_node(pxm, node); 77 node_set(node, nodes_found_map); 78 } 79 80 return node; 81 } 82 EXPORT_SYMBOL(acpi_map_pxm_to_node); 83 84 #ifdef CONFIG_NUMA_EMU 85 /* 86 * Take max_nid - 1 fake-numa nodes into account in both 87 * pxm_to_node_map()/node_to_pxm_map[] tables. 88 */ 89 int __init fix_pxm_node_maps(int max_nid) 90 { 91 static int pxm_to_node_map_copy[MAX_PXM_DOMAINS] __initdata 92 = { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE }; 93 static int node_to_pxm_map_copy[MAX_NUMNODES] __initdata 94 = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; 95 int i, j, index = -1, count = 0; 96 nodemask_t nodes_to_enable; 97 98 if (numa_off) 99 return -1; 100 101 /* no or incomplete node/PXM mapping set, nothing to do */ 102 if (srat_disabled()) 103 return 0; 104 105 /* find fake nodes PXM mapping */ 106 for (i = 0; i < MAX_NUMNODES; i++) { 107 if (node_to_pxm_map[i] != PXM_INVAL) { 108 for (j = 0; j <= max_nid; j++) { 109 if ((emu_nid_to_phys[j] == i) && 110 WARN(node_to_pxm_map_copy[j] != PXM_INVAL, 111 "Node %d is already binded to PXM %d\n", 112 j, node_to_pxm_map_copy[j])) 113 return -1; 114 if (emu_nid_to_phys[j] == i) { 115 node_to_pxm_map_copy[j] = 116 node_to_pxm_map[i]; 117 if (j > index) 118 index = j; 119 count++; 120 } 121 } 122 } 123 } 124 if (index == -1) { 125 pr_debug("No node/PXM mapping has been set\n"); 126 /* nothing more to be done */ 127 return 0; 128 } 129 if (WARN(index != max_nid, "%d max nid when expected %d\n", 130 index, max_nid)) 131 return -1; 132 133 nodes_clear(nodes_to_enable); 134 135 /* map phys nodes not used for fake nodes */ 136 for (i = 0; i < MAX_NUMNODES; i++) { 137 if (node_to_pxm_map[i] != PXM_INVAL) { 138 for (j = 0; j <= max_nid; j++) 139 if (emu_nid_to_phys[j] == i) 140 break; 141 /* fake nodes PXM mapping has been done */ 142 if (j <= max_nid) 143 continue; 144 /* find first hole */ 145 for (j = 0; 146 j < MAX_NUMNODES && 147 node_to_pxm_map_copy[j] != PXM_INVAL; 148 j++) 149 ; 150 if (WARN(j == MAX_NUMNODES, 151 "Number of nodes exceeds MAX_NUMNODES\n")) 152 return -1; 153 node_to_pxm_map_copy[j] = node_to_pxm_map[i]; 154 node_set(j, nodes_to_enable); 155 count++; 156 } 157 } 158 159 /* creating reverse mapping in pxm_to_node_map[] */ 160 for (i = 0; i < MAX_NUMNODES; i++) 161 if (node_to_pxm_map_copy[i] != PXM_INVAL && 162 pxm_to_node_map_copy[node_to_pxm_map_copy[i]] == NUMA_NO_NODE) 163 pxm_to_node_map_copy[node_to_pxm_map_copy[i]] = i; 164 165 /* overwrite with new mapping */ 166 for (i = 0; i < MAX_NUMNODES; i++) { 167 node_to_pxm_map[i] = node_to_pxm_map_copy[i]; 168 pxm_to_node_map[i] = pxm_to_node_map_copy[i]; 169 } 170 171 /* enable other nodes found in PXM for hotplug */ 172 nodes_or(numa_nodes_parsed, nodes_to_enable, numa_nodes_parsed); 173 174 pr_debug("found %d total number of nodes\n", count); 175 return 0; 176 } 177 #endif 178 179 static void __init 180 acpi_table_print_srat_entry(struct acpi_subtable_header *header) 181 { 182 switch (header->type) { 183 case ACPI_SRAT_TYPE_CPU_AFFINITY: 184 { 185 struct acpi_srat_cpu_affinity *p = 186 (struct acpi_srat_cpu_affinity *)header; 187 pr_debug("SRAT Processor (id[0x%02x] eid[0x%02x]) in proximity domain %d %s\n", 188 p->apic_id, p->local_sapic_eid, 189 p->proximity_domain_lo, 190 (p->flags & ACPI_SRAT_CPU_ENABLED) ? 191 "enabled" : "disabled"); 192 } 193 break; 194 195 case ACPI_SRAT_TYPE_MEMORY_AFFINITY: 196 { 197 struct acpi_srat_mem_affinity *p = 198 (struct acpi_srat_mem_affinity *)header; 199 pr_debug("SRAT Memory (0x%llx length 0x%llx) in proximity domain %d %s%s%s\n", 200 (unsigned long long)p->base_address, 201 (unsigned long long)p->length, 202 p->proximity_domain, 203 (p->flags & ACPI_SRAT_MEM_ENABLED) ? 204 "enabled" : "disabled", 205 (p->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) ? 206 " hot-pluggable" : "", 207 (p->flags & ACPI_SRAT_MEM_NON_VOLATILE) ? 208 " non-volatile" : ""); 209 } 210 break; 211 212 case ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY: 213 { 214 struct acpi_srat_x2apic_cpu_affinity *p = 215 (struct acpi_srat_x2apic_cpu_affinity *)header; 216 pr_debug("SRAT Processor (x2apicid[0x%08x]) in proximity domain %d %s\n", 217 p->apic_id, 218 p->proximity_domain, 219 (p->flags & ACPI_SRAT_CPU_ENABLED) ? 220 "enabled" : "disabled"); 221 } 222 break; 223 224 case ACPI_SRAT_TYPE_GICC_AFFINITY: 225 { 226 struct acpi_srat_gicc_affinity *p = 227 (struct acpi_srat_gicc_affinity *)header; 228 pr_debug("SRAT Processor (acpi id[0x%04x]) in proximity domain %d %s\n", 229 p->acpi_processor_uid, 230 p->proximity_domain, 231 (p->flags & ACPI_SRAT_GICC_ENABLED) ? 232 "enabled" : "disabled"); 233 } 234 break; 235 236 case ACPI_SRAT_TYPE_GENERIC_AFFINITY: 237 { 238 struct acpi_srat_generic_affinity *p = 239 (struct acpi_srat_generic_affinity *)header; 240 241 if (p->device_handle_type == 0) { 242 /* 243 * For pci devices this may be the only place they 244 * are assigned a proximity domain 245 */ 246 pr_debug("SRAT Generic Initiator(Seg:%u BDF:%u) in proximity domain %d %s\n", 247 *(u16 *)(&p->device_handle[0]), 248 *(u16 *)(&p->device_handle[2]), 249 p->proximity_domain, 250 (p->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED) ? 251 "enabled" : "disabled"); 252 } else { 253 /* 254 * In this case we can rely on the device having a 255 * proximity domain reference 256 */ 257 pr_debug("SRAT Generic Initiator(HID=%.8s UID=%.4s) in proximity domain %d %s\n", 258 (char *)(&p->device_handle[0]), 259 (char *)(&p->device_handle[8]), 260 p->proximity_domain, 261 (p->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED) ? 262 "enabled" : "disabled"); 263 } 264 } 265 break; 266 267 case ACPI_SRAT_TYPE_RINTC_AFFINITY: 268 { 269 struct acpi_srat_rintc_affinity *p = 270 (struct acpi_srat_rintc_affinity *)header; 271 pr_debug("SRAT Processor (acpi id[0x%04x]) in proximity domain %d %s\n", 272 p->acpi_processor_uid, 273 p->proximity_domain, 274 (p->flags & ACPI_SRAT_RINTC_ENABLED) ? 275 "enabled" : "disabled"); 276 } 277 break; 278 279 default: 280 pr_warn("Found unsupported SRAT entry (type = 0x%x)\n", 281 header->type); 282 break; 283 } 284 } 285 286 /* 287 * A lot of BIOS fill in 10 (= no distance) everywhere. This messes 288 * up the NUMA heuristics which wants the local node to have a smaller 289 * distance than the others. 290 * Do some quick checks here and only use the SLIT if it passes. 291 */ 292 static int __init slit_valid(struct acpi_table_slit *slit) 293 { 294 int i, j; 295 int d = slit->locality_count; 296 for (i = 0; i < d; i++) { 297 for (j = 0; j < d; j++) { 298 u8 val = slit->entry[d*i + j]; 299 if (i == j) { 300 if (val != LOCAL_DISTANCE) 301 return 0; 302 } else if (val <= LOCAL_DISTANCE) 303 return 0; 304 } 305 } 306 return 1; 307 } 308 309 void __init bad_srat(void) 310 { 311 pr_err("SRAT: SRAT not used.\n"); 312 disable_srat(); 313 } 314 315 int __init srat_disabled(void) 316 { 317 return acpi_numa < 0; 318 } 319 320 __weak int __init numa_fill_memblks(u64 start, u64 end) 321 { 322 return NUMA_NO_MEMBLK; 323 } 324 325 /* 326 * Callback for SLIT parsing. pxm_to_node() returns NUMA_NO_NODE for 327 * I/O localities since SRAT does not list them. I/O localities are 328 * not supported at this point. 329 */ 330 static int __init acpi_parse_slit(struct acpi_table_header *table) 331 { 332 struct acpi_table_slit *slit = (struct acpi_table_slit *)table; 333 int i, j; 334 335 if (!slit_valid(slit)) { 336 pr_info("SLIT table looks invalid. Not used.\n"); 337 return -EINVAL; 338 } 339 340 for (i = 0; i < slit->locality_count; i++) { 341 const int from_node = pxm_to_node(i); 342 343 if (from_node == NUMA_NO_NODE) 344 continue; 345 346 for (j = 0; j < slit->locality_count; j++) { 347 const int to_node = pxm_to_node(j); 348 349 if (to_node == NUMA_NO_NODE) 350 continue; 351 352 numa_set_distance(from_node, to_node, 353 slit->entry[slit->locality_count * i + j]); 354 } 355 } 356 357 return 0; 358 } 359 360 static int parsed_numa_memblks __initdata; 361 362 static int __init 363 acpi_parse_memory_affinity(union acpi_subtable_headers *header, 364 const unsigned long table_end) 365 { 366 struct acpi_srat_mem_affinity *ma; 367 u64 start, end; 368 u32 hotpluggable; 369 int node, pxm; 370 371 ma = (struct acpi_srat_mem_affinity *)header; 372 373 acpi_table_print_srat_entry(&header->common); 374 375 if (srat_disabled()) 376 return 0; 377 if (ma->header.length < sizeof(struct acpi_srat_mem_affinity)) { 378 pr_err("SRAT: Unexpected header length: %d\n", 379 ma->header.length); 380 goto out_err_bad_srat; 381 } 382 if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0) 383 return 0; 384 hotpluggable = IS_ENABLED(CONFIG_MEMORY_HOTPLUG) && 385 (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE); 386 387 start = ma->base_address; 388 end = start + ma->length; 389 pxm = ma->proximity_domain; 390 if (acpi_srat_revision <= 1) 391 pxm &= 0xff; 392 393 node = acpi_map_pxm_to_node(pxm); 394 if (node == NUMA_NO_NODE) { 395 pr_err("SRAT: Too many proximity domains.\n"); 396 goto out_err_bad_srat; 397 } 398 399 if (numa_add_memblk(node, start, end) < 0) { 400 pr_err("SRAT: Failed to add memblk to node %u [mem %#010Lx-%#010Lx]\n", 401 node, (unsigned long long) start, 402 (unsigned long long) end - 1); 403 goto out_err_bad_srat; 404 } 405 406 node_set(node, numa_nodes_parsed); 407 408 pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s%s\n", 409 node, pxm, 410 (unsigned long long) start, (unsigned long long) end - 1, 411 hotpluggable ? " hotplug" : "", 412 ma->flags & ACPI_SRAT_MEM_NON_VOLATILE ? " non-volatile" : ""); 413 414 /* Mark hotplug range in memblock. */ 415 if (hotpluggable && memblock_mark_hotplug(start, ma->length)) 416 pr_warn("SRAT: Failed to mark hotplug range [mem %#010Lx-%#010Lx] in memblock\n", 417 (unsigned long long)start, (unsigned long long)end - 1); 418 419 max_possible_pfn = max(max_possible_pfn, PFN_UP(end - 1)); 420 421 parsed_numa_memblks++; 422 423 return 0; 424 425 out_err_bad_srat: 426 /* Just disable SRAT, but do not fail and ignore errors. */ 427 bad_srat(); 428 429 return 0; 430 } 431 432 static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, 433 void *arg, const unsigned long table_end) 434 { 435 struct acpi_cedt_cfmws *cfmws; 436 int *fake_pxm = arg; 437 u64 start, end; 438 int node; 439 440 cfmws = (struct acpi_cedt_cfmws *)header; 441 start = cfmws->base_hpa; 442 end = cfmws->base_hpa + cfmws->window_size; 443 444 /* 445 * The SRAT may have already described NUMA details for all, 446 * or a portion of, this CFMWS HPA range. Extend the memblks 447 * found for any portion of the window to cover the entire 448 * window. 449 */ 450 if (!numa_fill_memblks(start, end)) 451 return 0; 452 453 /* No SRAT description. Create a new node. */ 454 node = acpi_map_pxm_to_node(*fake_pxm); 455 456 if (node == NUMA_NO_NODE) { 457 pr_err("ACPI NUMA: Too many proximity domains while processing CFMWS.\n"); 458 return -EINVAL; 459 } 460 461 if (numa_add_memblk(node, start, end) < 0) { 462 /* CXL driver must handle the NUMA_NO_NODE case */ 463 pr_warn("ACPI NUMA: Failed to add memblk for CFMWS node %d [mem %#llx-%#llx]\n", 464 node, start, end); 465 } 466 node_set(node, numa_nodes_parsed); 467 468 /* Set the next available fake_pxm value */ 469 (*fake_pxm)++; 470 return 0; 471 } 472 473 void __init __weak 474 acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa) 475 { 476 pr_warn("Found unsupported x2apic [0x%08x] SRAT entry\n", pa->apic_id); 477 } 478 479 static int __init 480 acpi_parse_x2apic_affinity(union acpi_subtable_headers *header, 481 const unsigned long end) 482 { 483 struct acpi_srat_x2apic_cpu_affinity *processor_affinity; 484 485 processor_affinity = (struct acpi_srat_x2apic_cpu_affinity *)header; 486 487 acpi_table_print_srat_entry(&header->common); 488 489 /* let architecture-dependent part to do it */ 490 acpi_numa_x2apic_affinity_init(processor_affinity); 491 492 return 0; 493 } 494 495 static int __init 496 acpi_parse_processor_affinity(union acpi_subtable_headers *header, 497 const unsigned long end) 498 { 499 struct acpi_srat_cpu_affinity *processor_affinity; 500 501 processor_affinity = (struct acpi_srat_cpu_affinity *)header; 502 503 acpi_table_print_srat_entry(&header->common); 504 505 /* let architecture-dependent part to do it */ 506 acpi_numa_processor_affinity_init(processor_affinity); 507 508 return 0; 509 } 510 511 static int __init 512 acpi_parse_gicc_affinity(union acpi_subtable_headers *header, 513 const unsigned long end) 514 { 515 struct acpi_srat_gicc_affinity *processor_affinity; 516 517 processor_affinity = (struct acpi_srat_gicc_affinity *)header; 518 519 acpi_table_print_srat_entry(&header->common); 520 521 /* let architecture-dependent part to do it */ 522 acpi_numa_gicc_affinity_init(processor_affinity); 523 524 return 0; 525 } 526 527 #if defined(CONFIG_X86) || defined(CONFIG_ARM64) 528 static int __init 529 acpi_parse_gi_affinity(union acpi_subtable_headers *header, 530 const unsigned long end) 531 { 532 struct acpi_srat_generic_affinity *gi_affinity; 533 int node; 534 535 gi_affinity = (struct acpi_srat_generic_affinity *)header; 536 if (!gi_affinity) 537 return -EINVAL; 538 acpi_table_print_srat_entry(&header->common); 539 540 if (!(gi_affinity->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED)) 541 return -EINVAL; 542 543 node = acpi_map_pxm_to_node(gi_affinity->proximity_domain); 544 if (node == NUMA_NO_NODE) { 545 pr_err("SRAT: Too many proximity domains.\n"); 546 return -EINVAL; 547 } 548 node_set(node, numa_nodes_parsed); 549 node_set_state(node, N_GENERIC_INITIATOR); 550 551 return 0; 552 } 553 #else 554 static int __init 555 acpi_parse_gi_affinity(union acpi_subtable_headers *header, 556 const unsigned long end) 557 { 558 return 0; 559 } 560 #endif /* defined(CONFIG_X86) || defined (CONFIG_ARM64) */ 561 562 static int __init 563 acpi_parse_rintc_affinity(union acpi_subtable_headers *header, 564 const unsigned long end) 565 { 566 struct acpi_srat_rintc_affinity *rintc_affinity; 567 568 rintc_affinity = (struct acpi_srat_rintc_affinity *)header; 569 acpi_table_print_srat_entry(&header->common); 570 571 /* let architecture-dependent part to do it */ 572 acpi_numa_rintc_affinity_init(rintc_affinity); 573 574 return 0; 575 } 576 577 static int __init acpi_parse_srat(struct acpi_table_header *table) 578 { 579 struct acpi_table_srat *srat = (struct acpi_table_srat *)table; 580 581 acpi_srat_revision = srat->header.revision; 582 583 /* Real work done in acpi_table_parse_srat below. */ 584 585 return 0; 586 } 587 588 static int __init 589 acpi_table_parse_srat(enum acpi_srat_type id, 590 acpi_tbl_entry_handler handler, unsigned int max_entries) 591 { 592 return acpi_table_parse_entries(ACPI_SIG_SRAT, 593 sizeof(struct acpi_table_srat), id, 594 handler, max_entries); 595 } 596 597 int __init acpi_numa_init(void) 598 { 599 int i, fake_pxm, cnt = 0; 600 601 if (acpi_disabled) 602 return -EINVAL; 603 604 /* 605 * Should not limit number with cpu num that is from NR_CPUS or nr_cpus= 606 * SRAT cpu entries could have different order with that in MADT. 607 * So go over all cpu entries in SRAT to get apicid to node mapping. 608 */ 609 610 /* SRAT: System Resource Affinity Table */ 611 if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) { 612 struct acpi_subtable_proc srat_proc[5]; 613 614 memset(srat_proc, 0, sizeof(srat_proc)); 615 srat_proc[0].id = ACPI_SRAT_TYPE_CPU_AFFINITY; 616 srat_proc[0].handler = acpi_parse_processor_affinity; 617 srat_proc[1].id = ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY; 618 srat_proc[1].handler = acpi_parse_x2apic_affinity; 619 srat_proc[2].id = ACPI_SRAT_TYPE_GICC_AFFINITY; 620 srat_proc[2].handler = acpi_parse_gicc_affinity; 621 srat_proc[3].id = ACPI_SRAT_TYPE_GENERIC_AFFINITY; 622 srat_proc[3].handler = acpi_parse_gi_affinity; 623 srat_proc[4].id = ACPI_SRAT_TYPE_RINTC_AFFINITY; 624 srat_proc[4].handler = acpi_parse_rintc_affinity; 625 626 acpi_table_parse_entries_array(ACPI_SIG_SRAT, 627 sizeof(struct acpi_table_srat), 628 srat_proc, ARRAY_SIZE(srat_proc), 0); 629 630 cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, 631 acpi_parse_memory_affinity, 0); 632 } 633 634 /* SLIT: System Locality Information Table */ 635 acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit); 636 637 /* 638 * CXL Fixed Memory Window Structures (CFMWS) must be parsed 639 * after the SRAT. Create NUMA Nodes for CXL memory ranges that 640 * are defined in the CFMWS and not already defined in the SRAT. 641 * Initialize a fake_pxm as the first available PXM to emulate. 642 */ 643 644 /* fake_pxm is the next unused PXM value after SRAT parsing */ 645 for (i = 0, fake_pxm = -1; i < MAX_NUMNODES; i++) { 646 if (node_to_pxm_map[i] > fake_pxm) 647 fake_pxm = node_to_pxm_map[i]; 648 } 649 last_real_pxm = fake_pxm; 650 fake_pxm++; 651 acpi_table_parse_cedt(ACPI_CEDT_TYPE_CFMWS, acpi_parse_cfmws, 652 &fake_pxm); 653 654 if (cnt < 0) 655 return cnt; 656 else if (!parsed_numa_memblks) 657 return -ENOENT; 658 return 0; 659 } 660 661 bool acpi_node_backed_by_real_pxm(int nid) 662 { 663 int pxm = node_to_pxm(nid); 664 665 return pxm <= last_real_pxm; 666 } 667 EXPORT_SYMBOL_GPL(acpi_node_backed_by_real_pxm); 668 669 static int acpi_get_pxm(acpi_handle h) 670 { 671 unsigned long long pxm; 672 acpi_status status; 673 acpi_handle handle; 674 acpi_handle phandle = h; 675 676 do { 677 handle = phandle; 678 status = acpi_evaluate_integer(handle, "_PXM", NULL, &pxm); 679 if (ACPI_SUCCESS(status)) 680 return pxm; 681 status = acpi_get_parent(handle, &phandle); 682 } while (ACPI_SUCCESS(status)); 683 return -1; 684 } 685 686 int acpi_get_node(acpi_handle handle) 687 { 688 int pxm; 689 690 pxm = acpi_get_pxm(handle); 691 692 return pxm_to_node(pxm); 693 } 694 EXPORT_SYMBOL(acpi_get_node); 695