1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * acpi_tables.c - ACPI Boot-Time Table Parsing
4 *
5 * Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 */
7
8/* Uncomment next line to get verbose printout */
9/* #define DEBUG */
10#define pr_fmt(fmt) "ACPI: " fmt
11
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/smp.h>
15#include <linux/string.h>
16#include <linux/types.h>
17#include <linux/irq.h>
18#include <linux/errno.h>
19#include <linux/acpi.h>
20#include <linux/memblock.h>
21#include <linux/earlycpio.h>
22#include <linux/initrd.h>
23#include <linux/security.h>
24#include <linux/kmemleak.h>
25#include "internal.h"
26
27#ifdef CONFIG_ACPI_CUSTOM_DSDT
28#include CONFIG_ACPI_CUSTOM_DSDT_FILE
29#endif
30
31#define ACPI_MAX_TABLES 128
32
33static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
34static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
35
36static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
37
38static int acpi_apic_instance __initdata_or_acpilib;
39
40/*
41 * Disable table checksum verification for the early stage due to the size
42 * limitation of the current x86 early mapping implementation.
43 */
44static bool acpi_verify_table_checksum __initdata_or_acpilib = false;
45
46void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
47{
48 if (!header)
49 return;
50
51 switch (header->type) {
52
53 case ACPI_MADT_TYPE_LOCAL_APIC:
54 {
55 struct acpi_madt_local_apic *p =
56 (struct acpi_madt_local_apic *)header;
57 pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
58 p->processor_id, p->id,
59 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
60 }
61 break;
62
63 case ACPI_MADT_TYPE_LOCAL_X2APIC:
64 {
65 struct acpi_madt_local_x2apic *p =
66 (struct acpi_madt_local_x2apic *)header;
67 pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
68 p->local_apic_id, p->uid,
69 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
70 }
71 break;
72
73 case ACPI_MADT_TYPE_IO_APIC:
74 {
75 struct acpi_madt_io_apic *p =
76 (struct acpi_madt_io_apic *)header;
77 pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
78 p->id, p->address, p->global_irq_base);
79 }
80 break;
81
82 case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
83 {
84 struct acpi_madt_interrupt_override *p =
85 (struct acpi_madt_interrupt_override *)header;
86 pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
87 p->bus, p->source_irq, p->global_irq,
88 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
89 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
90 if (p->inti_flags &
91 ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
92 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
93 p->inti_flags &
94 ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
95 }
96 break;
97
98 case ACPI_MADT_TYPE_NMI_SOURCE:
99 {
100 struct acpi_madt_nmi_source *p =
101 (struct acpi_madt_nmi_source *)header;
102 pr_info("NMI_SRC (%s %s global_irq %d)\n",
103 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
104 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
105 p->global_irq);
106 }
107 break;
108
109 case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
110 {
111 struct acpi_madt_local_apic_nmi *p =
112 (struct acpi_madt_local_apic_nmi *)header;
113 pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
114 p->processor_id,
115 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
116 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
117 p->lint);
118 }
119 break;
120
121 case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
122 {
123 u16 polarity, trigger;
124 struct acpi_madt_local_x2apic_nmi *p =
125 (struct acpi_madt_local_x2apic_nmi *)header;
126
127 polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
128 trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
129
130 pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
131 p->uid,
132 mps_inti_flags_polarity[polarity],
133 mps_inti_flags_trigger[trigger],
134 p->lint);
135 }
136 break;
137
138 case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
139 {
140 struct acpi_madt_local_apic_override *p =
141 (struct acpi_madt_local_apic_override *)header;
142 pr_info("LAPIC_ADDR_OVR (address[0x%llx])\n",
143 p->address);
144 }
145 break;
146
147 case ACPI_MADT_TYPE_IO_SAPIC:
148 {
149 struct acpi_madt_io_sapic *p =
150 (struct acpi_madt_io_sapic *)header;
151 pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
152 p->id, (void *)(unsigned long)p->address,
153 p->global_irq_base);
154 }
155 break;
156
157 case ACPI_MADT_TYPE_LOCAL_SAPIC:
158 {
159 struct acpi_madt_local_sapic *p =
160 (struct acpi_madt_local_sapic *)header;
161 pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
162 p->processor_id, p->id, p->eid,
163 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
164 }
165 break;
166
167 case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
168 {
169 struct acpi_madt_interrupt_source *p =
170 (struct acpi_madt_interrupt_source *)header;
171 pr_info("PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
172 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
173 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
174 p->type, p->id, p->eid, p->io_sapic_vector,
175 p->global_irq);
176 }
177 break;
178
179 case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
180 {
181 struct acpi_madt_generic_interrupt *p =
182 (struct acpi_madt_generic_interrupt *)header;
183 pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
184 p->uid, p->base_address,
185 p->arm_mpidr,
186 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
187
188 }
189 break;
190
191 case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
192 {
193 struct acpi_madt_generic_distributor *p =
194 (struct acpi_madt_generic_distributor *)header;
195 pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
196 p->gic_id, p->base_address,
197 p->global_irq_base);
198 }
199 break;
200
201 case ACPI_MADT_TYPE_CORE_PIC:
202 {
203 struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
204
205 pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
206 p->processor_id, p->core_id,
207 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
208 }
209 break;
210
211 case ACPI_MADT_TYPE_RINTC:
212 {
213 struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
214
215 pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
216 p->uid, p->hart_id,
217 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
218 }
219 break;
220
221 default:
222 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
223 header->type);
224 break;
225 }
226}
227
228int __init_or_acpilib acpi_table_parse_entries_array(
229 char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
230 int proc_num, unsigned int max_entries)
231{
232 struct acpi_table_header *table_header = NULL;
233 int count;
234 u32 instance = 0;
235
236 if (acpi_disabled)
237 return -ENODEV;
238
239 if (!id)
240 return -EINVAL;
241
242 if (!table_size)
243 return -EINVAL;
244
245 if (!strncmp(id, ACPI_SIG_MADT, 4))
246 instance = acpi_apic_instance;
247
248 acpi_get_table(signature: id, instance, out_table: &table_header);
249 if (!table_header) {
250 pr_debug("%4.4s not present\n", id);
251 return -ENODEV;
252 }
253
254 count = acpi_parse_entries_array(id, table_size,
255 table_header: (union fw_table_header *)table_header,
256 max_length: 0, proc, proc_num, max_entries);
257
258 acpi_put_table(table: table_header);
259 return count;
260}
261
262static int __init_or_acpilib __acpi_table_parse_entries(
263 char *id, unsigned long table_size, int entry_id,
264 acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
265 void *arg, unsigned int max_entries)
266{
267 struct acpi_subtable_proc proc = {
268 .id = entry_id,
269 .handler = handler,
270 .handler_arg = handler_arg,
271 .arg = arg,
272 };
273
274 return acpi_table_parse_entries_array(id, table_size, proc: &proc, proc_num: 1,
275 max_entries);
276}
277
278int __init_or_acpilib
279acpi_table_parse_cedt(enum acpi_cedt_type id,
280 acpi_tbl_entry_handler_arg handler_arg, void *arg)
281{
282 return __acpi_table_parse_entries(ACPI_SIG_CEDT,
283 table_size: sizeof(struct acpi_table_cedt), entry_id: id,
284 NULL, handler_arg, arg, max_entries: 0);
285}
286EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
287
288int __init acpi_table_parse_entries(char *id, unsigned long table_size,
289 int entry_id,
290 acpi_tbl_entry_handler handler,
291 unsigned int max_entries)
292{
293 return __acpi_table_parse_entries(id, table_size, entry_id, handler,
294 NULL, NULL, max_entries);
295}
296
297int __init acpi_table_parse_madt(enum acpi_madt_type id,
298 acpi_tbl_entry_handler handler, unsigned int max_entries)
299{
300 return acpi_table_parse_entries(ACPI_SIG_MADT,
301 table_size: sizeof(struct acpi_table_madt), entry_id: id,
302 handler, max_entries);
303}
304
305/**
306 * acpi_table_parse - find table with @id, run @handler on it
307 * @id: table id to find
308 * @handler: handler to run
309 *
310 * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
311 * run @handler on it.
312 *
313 * Return 0 if table found, -errno if not.
314 */
315int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
316{
317 struct acpi_table_header *table = NULL;
318
319 if (acpi_disabled)
320 return -ENODEV;
321
322 if (!id || !handler)
323 return -EINVAL;
324
325 if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
326 acpi_get_table(signature: id, instance: acpi_apic_instance, out_table: &table);
327 else
328 acpi_get_table(signature: id, instance: 0, out_table: &table);
329
330 if (table) {
331 handler(table);
332 acpi_put_table(table);
333 return 0;
334 } else
335 return -ENODEV;
336}
337
338/*
339 * The BIOS is supposed to supply a single APIC/MADT,
340 * but some report two. Provide a knob to use either.
341 * (don't you wish instance 0 and 1 were not the same?)
342 */
343static void __init check_multiple_madt(void)
344{
345 struct acpi_table_header *table = NULL;
346
347 acpi_get_table(ACPI_SIG_MADT, instance: 2, out_table: &table);
348 if (table) {
349 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
350 acpi_apic_instance);
351 pr_warn("If \"acpi_apic_instance=%d\" works better, "
352 "notify linux-acpi@vger.kernel.org\n",
353 acpi_apic_instance ? 0 : 2);
354 acpi_put_table(table);
355
356 } else
357 acpi_apic_instance = 0;
358
359 return;
360}
361
362static void acpi_table_taint(struct acpi_table_header *table)
363{
364 pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
365 table->signature, table->oem_table_id);
366 add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
367}
368
369#ifdef CONFIG_ACPI_TABLE_UPGRADE
370static u64 acpi_tables_addr;
371static int all_tables_size;
372
373/* Copied from acpica/tbutils.c:acpi_tb_checksum() */
374static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
375{
376 u8 sum = 0;
377 u8 *end = buffer + length;
378
379 while (buffer < end)
380 sum = (u8) (sum + *(buffer++));
381 return sum;
382}
383
384/* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
385static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
386 ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
387 ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
388 ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
389 ACPI_SIG_ASF, ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
390 ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
391 ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
392 ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
393 ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
394 ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
395 ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
396 ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
397 ACPI_SIG_NBFT };
398
399#define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
400
401#define NR_ACPI_INITRD_TABLES 64
402static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
403static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
404
405#define MAP_CHUNK_SIZE (NR_FIX_BTMAPS << PAGE_SHIFT)
406
407void __init acpi_table_upgrade(void)
408{
409 void *data;
410 size_t size;
411 int sig, no, table_nr = 0, total_offset = 0;
412 long offset = 0;
413 struct acpi_table_header *table;
414 char cpio_path[32] = "kernel/firmware/acpi/";
415 struct cpio_data file;
416
417 if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
418 data = __initramfs_start;
419 size = __initramfs_size;
420 } else {
421 data = (void *)initrd_start;
422 size = initrd_end - initrd_start;
423 }
424
425 if (data == NULL || size == 0)
426 return;
427
428 for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
429 file = find_cpio_data(path: cpio_path, data, len: size, offset: &offset);
430 if (!file.data)
431 break;
432
433 data += offset;
434 size -= offset;
435
436 if (file.size < sizeof(struct acpi_table_header)) {
437 pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
438 cpio_path, file.name);
439 continue;
440 }
441
442 table = file.data;
443
444 for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
445 if (!memcmp(p: table->signature, q: table_sigs[sig], size: 4))
446 break;
447
448 if (sig >= ARRAY_SIZE(table_sigs)) {
449 pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
450 cpio_path, file.name);
451 continue;
452 }
453 if (file.size != table->length) {
454 pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
455 cpio_path, file.name);
456 continue;
457 }
458 if (acpi_table_checksum(buffer: file.data, length: table->length)) {
459 pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
460 cpio_path, file.name);
461 continue;
462 }
463
464 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
465 table->signature, cpio_path, file.name, table->length);
466
467 all_tables_size += table->length;
468 acpi_initrd_files[table_nr].data = file.data;
469 acpi_initrd_files[table_nr].size = file.size;
470 table_nr++;
471 }
472 if (table_nr == 0)
473 return;
474
475 if (security_locked_down(what: LOCKDOWN_ACPI_TABLES)) {
476 pr_notice("kernel is locked down, ignoring table override\n");
477 return;
478 }
479
480 acpi_tables_addr =
481 memblock_phys_alloc_range(size: all_tables_size, PAGE_SIZE,
482 start: 0, ACPI_TABLE_UPGRADE_MAX_PHYS);
483 if (!acpi_tables_addr) {
484 WARN_ON(1);
485 return;
486 }
487 /*
488 * Only calling e820_add_reserve does not work and the
489 * tables are invalid (memory got used) later.
490 * memblock_reserve works as expected and the tables won't get modified.
491 * But it's not enough on X86 because ioremap will
492 * complain later (used by acpi_os_map_memory) that the pages
493 * that should get mapped are not marked "reserved".
494 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
495 * works fine.
496 */
497 arch_reserve_mem_area(addr: acpi_tables_addr, size: all_tables_size);
498
499 kmemleak_ignore_phys(phys: acpi_tables_addr);
500
501 /*
502 * early_ioremap only can remap 256k one time. If we map all
503 * tables one time, we will hit the limit. Need to map chunks
504 * one by one during copying the same as that in relocate_initrd().
505 */
506 for (no = 0; no < table_nr; no++) {
507 unsigned char *src_p = acpi_initrd_files[no].data;
508 phys_addr_t size = acpi_initrd_files[no].size;
509 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
510 phys_addr_t slop, clen;
511 char *dest_p;
512
513 total_offset += size;
514
515 while (size) {
516 slop = dest_addr & ~PAGE_MASK;
517 clen = size;
518 if (clen > MAP_CHUNK_SIZE - slop)
519 clen = MAP_CHUNK_SIZE - slop;
520 dest_p = early_memremap(phys_addr: dest_addr & PAGE_MASK,
521 size: clen + slop);
522 memcpy(dest_p + slop, src_p, clen);
523 early_memunmap(addr: dest_p, size: clen + slop);
524 src_p += clen;
525 dest_addr += clen;
526 size -= clen;
527 }
528 }
529}
530
531static acpi_status
532acpi_table_initrd_override(struct acpi_table_header *existing_table,
533 acpi_physical_address *address, u32 *length)
534{
535 int table_offset = 0;
536 int table_index = 0;
537 struct acpi_table_header *table;
538 u32 table_length;
539
540 *length = 0;
541 *address = 0;
542 if (!acpi_tables_addr)
543 return AE_OK;
544
545 while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
546 table = acpi_os_map_memory(where: acpi_tables_addr + table_offset,
547 ACPI_HEADER_SIZE);
548 if (table_offset + table->length > all_tables_size) {
549 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
550 WARN_ON(1);
551 return AE_OK;
552 }
553
554 table_length = table->length;
555
556 /* Only override tables matched */
557 if (memcmp(p: existing_table->signature, q: table->signature, size: 4) ||
558 memcmp(p: table->oem_id, q: existing_table->oem_id,
559 ACPI_OEM_ID_SIZE) ||
560 memcmp(p: table->oem_table_id, q: existing_table->oem_table_id,
561 ACPI_OEM_TABLE_ID_SIZE)) {
562 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
563 goto next_table;
564 }
565 /*
566 * Mark the table to avoid being used in
567 * acpi_table_initrd_scan() and check the revision.
568 */
569 if (test_and_set_bit(nr: table_index, addr: acpi_initrd_installed) ||
570 existing_table->oem_revision >= table->oem_revision) {
571 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
572 goto next_table;
573 }
574
575 *length = table_length;
576 *address = acpi_tables_addr + table_offset;
577 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
578 table->signature, table->oem_id,
579 table->oem_table_id);
580 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
581 break;
582
583next_table:
584 table_offset += table_length;
585 table_index++;
586 }
587 return AE_OK;
588}
589
590static void __init acpi_table_initrd_scan(void)
591{
592 int table_offset = 0;
593 int table_index = 0;
594 u32 table_length;
595 struct acpi_table_header *table;
596
597 if (!acpi_tables_addr)
598 return;
599
600 while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
601 table = acpi_os_map_memory(where: acpi_tables_addr + table_offset,
602 ACPI_HEADER_SIZE);
603 if (table_offset + table->length > all_tables_size) {
604 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
605 WARN_ON(1);
606 return;
607 }
608
609 table_length = table->length;
610
611 /* Skip RSDT/XSDT which should only be used for override */
612 if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
613 ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
614 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
615 goto next_table;
616 }
617 /*
618 * Mark the table to avoid being used in
619 * acpi_table_initrd_override(). Though this is not possible
620 * because override is disabled in acpi_install_physical_table().
621 */
622 if (test_and_set_bit(nr: table_index, addr: acpi_initrd_installed)) {
623 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
624 goto next_table;
625 }
626
627 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
628 table->signature, table->oem_id,
629 table->oem_table_id);
630 acpi_os_unmap_memory(logical_address: table, ACPI_HEADER_SIZE);
631 acpi_install_physical_table(address: acpi_tables_addr + table_offset);
632next_table:
633 table_offset += table_length;
634 table_index++;
635 }
636}
637#else
638static acpi_status
639acpi_table_initrd_override(struct acpi_table_header *existing_table,
640 acpi_physical_address *address,
641 u32 *table_length)
642{
643 *table_length = 0;
644 *address = 0;
645 return AE_OK;
646}
647
648static void __init acpi_table_initrd_scan(void)
649{
650}
651#endif /* CONFIG_ACPI_TABLE_UPGRADE */
652
653acpi_status
654acpi_os_physical_table_override(struct acpi_table_header *existing_table,
655 acpi_physical_address *address,
656 u32 *table_length)
657{
658 return acpi_table_initrd_override(existing_table, address,
659 length: table_length);
660}
661
662#ifdef CONFIG_ACPI_CUSTOM_DSDT
663static void *amlcode __attribute__ ((weakref("AmlCode")));
664static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
665#endif
666
667acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
668 struct acpi_table_header **new_table)
669{
670 if (!existing_table || !new_table)
671 return AE_BAD_PARAMETER;
672
673 *new_table = NULL;
674
675#ifdef CONFIG_ACPI_CUSTOM_DSDT
676 if (!strncmp(existing_table->signature, "DSDT", 4)) {
677 *new_table = (struct acpi_table_header *)&amlcode;
678 if (!(*new_table))
679 *new_table = (struct acpi_table_header *)&dsdt_amlcode;
680 }
681#endif
682 if (*new_table != NULL)
683 acpi_table_taint(table: existing_table);
684 return AE_OK;
685}
686
687/*
688 * acpi_locate_initial_tables()
689 *
690 * Get the RSDP, then find and checksum all the ACPI tables.
691 *
692 * result: initial_tables[] is initialized, and points to
693 * a list of ACPI tables.
694 */
695int __init acpi_locate_initial_tables(void)
696{
697 acpi_status status;
698
699 if (acpi_verify_table_checksum) {
700 pr_info("Early table checksum verification enabled\n");
701 acpi_gbl_enable_table_validation = TRUE;
702 } else {
703 pr_info("Early table checksum verification disabled\n");
704 acpi_gbl_enable_table_validation = FALSE;
705 }
706
707 status = acpi_initialize_tables(initial_storage: initial_tables, ACPI_MAX_TABLES, allow_resize: 0);
708 if (ACPI_FAILURE(status))
709 return -EINVAL;
710
711 return 0;
712}
713
714void __init acpi_reserve_initial_tables(void)
715{
716 int i;
717
718 for (i = 0; i < ACPI_MAX_TABLES; i++) {
719 struct acpi_table_desc *table_desc = &initial_tables[i];
720 u64 start = table_desc->address;
721 u64 size = table_desc->length;
722
723 if (!start || !size)
724 break;
725
726 pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
727 table_desc->signature.ascii, start, start + size - 1);
728
729 memblock_reserve(base: start, size);
730 }
731}
732
733void __init acpi_table_init_complete(void)
734{
735 acpi_table_initrd_scan();
736 check_multiple_madt();
737}
738
739int __init acpi_table_init(void)
740{
741 int ret;
742
743 ret = acpi_locate_initial_tables();
744 if (ret)
745 return ret;
746
747 acpi_table_init_complete();
748
749 return 0;
750}
751
752static int __init acpi_parse_apic_instance(char *str)
753{
754 if (!str)
755 return -EINVAL;
756
757 if (kstrtoint(s: str, base: 0, res: &acpi_apic_instance))
758 return -EINVAL;
759
760 pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
761
762 return 0;
763}
764early_param("acpi_apic_instance", acpi_parse_apic_instance);
765
766static int __init acpi_force_table_verification_setup(char *s)
767{
768 acpi_verify_table_checksum = true;
769
770 return 0;
771}
772early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
773
774static int __init acpi_force_32bit_fadt_addr(char *s)
775{
776 pr_info("Forcing 32 Bit FADT addresses\n");
777 acpi_gbl_use32_bit_fadt_addresses = TRUE;
778
779 return 0;
780}
781early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
782

source code of linux/drivers/acpi/tables.c