x86/smpboot: Init apic mapping before usage
[cascardo/linux.git] / drivers / acpi / tables.c
1 /*
2  *  acpi_tables.c - ACPI Boot-Time Table Parsing
3  *
4  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
19  *
20  */
21
22 /* Uncomment next line to get verbose printout */
23 /* #define DEBUG */
24 #define pr_fmt(fmt) "ACPI: " fmt
25
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/smp.h>
29 #include <linux/string.h>
30 #include <linux/types.h>
31 #include <linux/irq.h>
32 #include <linux/errno.h>
33 #include <linux/acpi.h>
34 #include <linux/bootmem.h>
35 #include <linux/earlycpio.h>
36 #include <linux/memblock.h>
37 #include <linux/initrd.h>
38 #include "internal.h"
39
40 #ifdef CONFIG_ACPI_CUSTOM_DSDT
41 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
42 #endif
43
44 #define ACPI_MAX_TABLES         128
45
46 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
47 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
48
49 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
50
51 static int acpi_apic_instance __initdata;
52
53 /*
54  * Disable table checksum verification for the early stage due to the size
55  * limitation of the current x86 early mapping implementation.
56  */
57 static bool acpi_verify_table_checksum __initdata = false;
58
59 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
60 {
61         if (!header)
62                 return;
63
64         switch (header->type) {
65
66         case ACPI_MADT_TYPE_LOCAL_APIC:
67                 {
68                         struct acpi_madt_local_apic *p =
69                             (struct acpi_madt_local_apic *)header;
70                         pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
71                                  p->processor_id, p->id,
72                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
73                 }
74                 break;
75
76         case ACPI_MADT_TYPE_LOCAL_X2APIC:
77                 {
78                         struct acpi_madt_local_x2apic *p =
79                             (struct acpi_madt_local_x2apic *)header;
80                         pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
81                                  p->local_apic_id, p->uid,
82                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
83                 }
84                 break;
85
86         case ACPI_MADT_TYPE_IO_APIC:
87                 {
88                         struct acpi_madt_io_apic *p =
89                             (struct acpi_madt_io_apic *)header;
90                         pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
91                                  p->id, p->address, p->global_irq_base);
92                 }
93                 break;
94
95         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
96                 {
97                         struct acpi_madt_interrupt_override *p =
98                             (struct acpi_madt_interrupt_override *)header;
99                         pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
100                                 p->bus, p->source_irq, p->global_irq,
101                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
102                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
103                         if (p->inti_flags  &
104                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
105                                 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
106                                         p->inti_flags  &
107                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
108                 }
109                 break;
110
111         case ACPI_MADT_TYPE_NMI_SOURCE:
112                 {
113                         struct acpi_madt_nmi_source *p =
114                             (struct acpi_madt_nmi_source *)header;
115                         pr_info("NMI_SRC (%s %s global_irq %d)\n",
116                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
117                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
118                                 p->global_irq);
119                 }
120                 break;
121
122         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
123                 {
124                         struct acpi_madt_local_apic_nmi *p =
125                             (struct acpi_madt_local_apic_nmi *)header;
126                         pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
127                                 p->processor_id,
128                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
129                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
130                                 p->lint);
131                 }
132                 break;
133
134         case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
135                 {
136                         u16 polarity, trigger;
137                         struct acpi_madt_local_x2apic_nmi *p =
138                             (struct acpi_madt_local_x2apic_nmi *)header;
139
140                         polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
141                         trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
142
143                         pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
144                                 p->uid,
145                                 mps_inti_flags_polarity[polarity],
146                                 mps_inti_flags_trigger[trigger],
147                                 p->lint);
148                 }
149                 break;
150
151         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
152                 {
153                         struct acpi_madt_local_apic_override *p =
154                             (struct acpi_madt_local_apic_override *)header;
155                         pr_info("LAPIC_ADDR_OVR (address[%p])\n",
156                                 (void *)(unsigned long)p->address);
157                 }
158                 break;
159
160         case ACPI_MADT_TYPE_IO_SAPIC:
161                 {
162                         struct acpi_madt_io_sapic *p =
163                             (struct acpi_madt_io_sapic *)header;
164                         pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
165                                  p->id, (void *)(unsigned long)p->address,
166                                  p->global_irq_base);
167                 }
168                 break;
169
170         case ACPI_MADT_TYPE_LOCAL_SAPIC:
171                 {
172                         struct acpi_madt_local_sapic *p =
173                             (struct acpi_madt_local_sapic *)header;
174                         pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
175                                  p->processor_id, p->id, p->eid,
176                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
177                 }
178                 break;
179
180         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
181                 {
182                         struct acpi_madt_interrupt_source *p =
183                             (struct acpi_madt_interrupt_source *)header;
184                         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",
185                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
186                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
187                                 p->type, p->id, p->eid, p->io_sapic_vector,
188                                 p->global_irq);
189                 }
190                 break;
191
192         case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
193                 {
194                         struct acpi_madt_generic_interrupt *p =
195                                 (struct acpi_madt_generic_interrupt *)header;
196                         pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
197                                  p->uid, p->base_address,
198                                  p->arm_mpidr,
199                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
200
201                 }
202                 break;
203
204         case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
205                 {
206                         struct acpi_madt_generic_distributor *p =
207                                 (struct acpi_madt_generic_distributor *)header;
208                         pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
209                                  p->gic_id, p->base_address,
210                                  p->global_irq_base);
211                 }
212                 break;
213
214         default:
215                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
216                         header->type);
217                 break;
218         }
219 }
220
221 /**
222  * acpi_parse_entries_array - for each proc_num find a suitable subtable
223  *
224  * @id: table id (for debugging purposes)
225  * @table_size: single entry size
226  * @table_header: where does the table start?
227  * @proc: array of acpi_subtable_proc struct containing entry id
228  *        and associated handler with it
229  * @proc_num: how big proc is?
230  * @max_entries: how many entries can we process?
231  *
232  * For each proc_num find a subtable with proc->id and run proc->handler
233  * on it. Assumption is that there's only single handler for particular
234  * entry id.
235  *
236  * On success returns sum of all matching entries for all proc handlers.
237  * Otherwise, -ENODEV or -EINVAL is returned.
238  */
239 static int __init
240 acpi_parse_entries_array(char *id, unsigned long table_size,
241                 struct acpi_table_header *table_header,
242                 struct acpi_subtable_proc *proc, int proc_num,
243                 unsigned int max_entries)
244 {
245         struct acpi_subtable_header *entry;
246         unsigned long table_end;
247         int count = 0;
248         int errs = 0;
249         int i;
250
251         if (acpi_disabled)
252                 return -ENODEV;
253
254         if (!id)
255                 return -EINVAL;
256
257         if (!table_size)
258                 return -EINVAL;
259
260         if (!table_header) {
261                 pr_warn("%4.4s not present\n", id);
262                 return -ENODEV;
263         }
264
265         table_end = (unsigned long)table_header + table_header->length;
266
267         /* Parse all entries looking for a match. */
268
269         entry = (struct acpi_subtable_header *)
270             ((unsigned long)table_header + table_size);
271
272         while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
273                table_end) {
274                 if (max_entries && count >= max_entries)
275                         break;
276
277                 for (i = 0; i < proc_num; i++) {
278                         if (entry->type != proc[i].id)
279                                 continue;
280                         if (!proc[i].handler ||
281                              (!errs && proc[i].handler(entry, table_end))) {
282                                 errs++;
283                                 continue;
284                         }
285
286                         proc[i].count++;
287                         break;
288                 }
289                 if (i != proc_num)
290                         count++;
291
292                 /*
293                  * If entry->length is 0, break from this loop to avoid
294                  * infinite loop.
295                  */
296                 if (entry->length == 0) {
297                         pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
298                         return -EINVAL;
299                 }
300
301                 entry = (struct acpi_subtable_header *)
302                     ((unsigned long)entry + entry->length);
303         }
304
305         if (max_entries && count > max_entries) {
306                 pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
307                         id, proc->id, count);
308         }
309
310         return errs ? -EINVAL : count;
311 }
312
313 int __init
314 acpi_parse_entries(char *id,
315                         unsigned long table_size,
316                         acpi_tbl_entry_handler handler,
317                         struct acpi_table_header *table_header,
318                         int entry_id, unsigned int max_entries)
319 {
320         struct acpi_subtable_proc proc = {
321                 .id             = entry_id,
322                 .handler        = handler,
323         };
324
325         return acpi_parse_entries_array(id, table_size, table_header,
326                         &proc, 1, max_entries);
327 }
328
329 int __init
330 acpi_table_parse_entries_array(char *id,
331                          unsigned long table_size,
332                          struct acpi_subtable_proc *proc, int proc_num,
333                          unsigned int max_entries)
334 {
335         struct acpi_table_header *table_header = NULL;
336         acpi_size tbl_size;
337         int count;
338         u32 instance = 0;
339
340         if (acpi_disabled)
341                 return -ENODEV;
342
343         if (!id)
344                 return -EINVAL;
345
346         if (!strncmp(id, ACPI_SIG_MADT, 4))
347                 instance = acpi_apic_instance;
348
349         acpi_get_table_with_size(id, instance, &table_header, &tbl_size);
350         if (!table_header) {
351                 pr_warn("%4.4s not present\n", id);
352                 return -ENODEV;
353         }
354
355         count = acpi_parse_entries_array(id, table_size, table_header,
356                         proc, proc_num, max_entries);
357
358         early_acpi_os_unmap_memory((char *)table_header, tbl_size);
359         return count;
360 }
361
362 int __init
363 acpi_table_parse_entries(char *id,
364                         unsigned long table_size,
365                         int entry_id,
366                         acpi_tbl_entry_handler handler,
367                         unsigned int max_entries)
368 {
369         struct acpi_subtable_proc proc = {
370                 .id             = entry_id,
371                 .handler        = handler,
372         };
373
374         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
375                                                 max_entries);
376 }
377
378 int __init
379 acpi_table_parse_madt(enum acpi_madt_type id,
380                       acpi_tbl_entry_handler handler, unsigned int max_entries)
381 {
382         return acpi_table_parse_entries(ACPI_SIG_MADT,
383                                             sizeof(struct acpi_table_madt), id,
384                                             handler, max_entries);
385 }
386
387 /**
388  * acpi_table_parse - find table with @id, run @handler on it
389  * @id: table id to find
390  * @handler: handler to run
391  *
392  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
393  * run @handler on it.
394  *
395  * Return 0 if table found, -errno if not.
396  */
397 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
398 {
399         struct acpi_table_header *table = NULL;
400         acpi_size tbl_size;
401
402         if (acpi_disabled)
403                 return -ENODEV;
404
405         if (!id || !handler)
406                 return -EINVAL;
407
408         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
409                 acpi_get_table_with_size(id, acpi_apic_instance, &table, &tbl_size);
410         else
411                 acpi_get_table_with_size(id, 0, &table, &tbl_size);
412
413         if (table) {
414                 handler(table);
415                 early_acpi_os_unmap_memory(table, tbl_size);
416                 return 0;
417         } else
418                 return -ENODEV;
419 }
420
421 /* 
422  * The BIOS is supposed to supply a single APIC/MADT,
423  * but some report two.  Provide a knob to use either.
424  * (don't you wish instance 0 and 1 were not the same?)
425  */
426 static void __init check_multiple_madt(void)
427 {
428         struct acpi_table_header *table = NULL;
429         acpi_size tbl_size;
430
431         acpi_get_table_with_size(ACPI_SIG_MADT, 2, &table, &tbl_size);
432         if (table) {
433                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
434                         acpi_apic_instance);
435                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
436                         "notify linux-acpi@vger.kernel.org\n",
437                         acpi_apic_instance ? 0 : 2);
438                 early_acpi_os_unmap_memory(table, tbl_size);
439
440         } else
441                 acpi_apic_instance = 0;
442
443         return;
444 }
445
446 static void acpi_table_taint(struct acpi_table_header *table)
447 {
448         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
449                 table->signature, table->oem_table_id);
450         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
451 }
452
453 #ifdef CONFIG_ACPI_TABLE_UPGRADE
454 static u64 acpi_tables_addr;
455 static int all_tables_size;
456
457 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
458 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
459 {
460         u8 sum = 0;
461         u8 *end = buffer + length;
462
463         while (buffer < end)
464                 sum = (u8) (sum + *(buffer++));
465         return sum;
466 }
467
468 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
469 static const char * const table_sigs[] = {
470         ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
471         ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
472         ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
473         ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
474         ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
475         ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
476         ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
477         ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
478         ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, NULL };
479
480 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
481
482 #define NR_ACPI_INITRD_TABLES 64
483 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
484 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
485
486 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
487
488 void __init acpi_table_upgrade(void)
489 {
490         void *data = (void *)initrd_start;
491         size_t size = initrd_end - initrd_start;
492         int sig, no, table_nr = 0, total_offset = 0;
493         long offset = 0;
494         struct acpi_table_header *table;
495         char cpio_path[32] = "kernel/firmware/acpi/";
496         struct cpio_data file;
497
498         if (data == NULL || size == 0)
499                 return;
500
501         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
502                 file = find_cpio_data(cpio_path, data, size, &offset);
503                 if (!file.data)
504                         break;
505
506                 data += offset;
507                 size -= offset;
508
509                 if (file.size < sizeof(struct acpi_table_header)) {
510                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
511                                 cpio_path, file.name);
512                         continue;
513                 }
514
515                 table = file.data;
516
517                 for (sig = 0; table_sigs[sig]; sig++)
518                         if (!memcmp(table->signature, table_sigs[sig], 4))
519                                 break;
520
521                 if (!table_sigs[sig]) {
522                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
523                                 cpio_path, file.name);
524                         continue;
525                 }
526                 if (file.size != table->length) {
527                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
528                                 cpio_path, file.name);
529                         continue;
530                 }
531                 if (acpi_table_checksum(file.data, table->length)) {
532                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
533                                 cpio_path, file.name);
534                         continue;
535                 }
536
537                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
538                         table->signature, cpio_path, file.name, table->length);
539
540                 all_tables_size += table->length;
541                 acpi_initrd_files[table_nr].data = file.data;
542                 acpi_initrd_files[table_nr].size = file.size;
543                 table_nr++;
544         }
545         if (table_nr == 0)
546                 return;
547
548         acpi_tables_addr =
549                 memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
550                                        all_tables_size, PAGE_SIZE);
551         if (!acpi_tables_addr) {
552                 WARN_ON(1);
553                 return;
554         }
555         /*
556          * Only calling e820_add_reserve does not work and the
557          * tables are invalid (memory got used) later.
558          * memblock_reserve works as expected and the tables won't get modified.
559          * But it's not enough on X86 because ioremap will
560          * complain later (used by acpi_os_map_memory) that the pages
561          * that should get mapped are not marked "reserved".
562          * Both memblock_reserve and e820_add_region (via arch_reserve_mem_area)
563          * works fine.
564          */
565         memblock_reserve(acpi_tables_addr, all_tables_size);
566         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
567
568         /*
569          * early_ioremap only can remap 256k one time. If we map all
570          * tables one time, we will hit the limit. Need to map chunks
571          * one by one during copying the same as that in relocate_initrd().
572          */
573         for (no = 0; no < table_nr; no++) {
574                 unsigned char *src_p = acpi_initrd_files[no].data;
575                 phys_addr_t size = acpi_initrd_files[no].size;
576                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
577                 phys_addr_t slop, clen;
578                 char *dest_p;
579
580                 total_offset += size;
581
582                 while (size) {
583                         slop = dest_addr & ~PAGE_MASK;
584                         clen = size;
585                         if (clen > MAP_CHUNK_SIZE - slop)
586                                 clen = MAP_CHUNK_SIZE - slop;
587                         dest_p = early_memremap(dest_addr & PAGE_MASK,
588                                                 clen + slop);
589                         memcpy(dest_p + slop, src_p, clen);
590                         early_memunmap(dest_p, clen + slop);
591                         src_p += clen;
592                         dest_addr += clen;
593                         size -= clen;
594                 }
595         }
596 }
597
598 static acpi_status
599 acpi_table_initrd_override(struct acpi_table_header *existing_table,
600                            acpi_physical_address *address, u32 *length)
601 {
602         int table_offset = 0;
603         int table_index = 0;
604         struct acpi_table_header *table;
605         u32 table_length;
606
607         *length = 0;
608         *address = 0;
609         if (!acpi_tables_addr)
610                 return AE_OK;
611
612         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
613                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
614                                            ACPI_HEADER_SIZE);
615                 if (table_offset + table->length > all_tables_size) {
616                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
617                         WARN_ON(1);
618                         return AE_OK;
619                 }
620
621                 table_length = table->length;
622
623                 /* Only override tables matched */
624                 if (memcmp(existing_table->signature, table->signature, 4) ||
625                     memcmp(table->oem_id, existing_table->oem_id,
626                            ACPI_OEM_ID_SIZE) ||
627                     memcmp(table->oem_table_id, existing_table->oem_table_id,
628                            ACPI_OEM_TABLE_ID_SIZE)) {
629                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
630                         goto next_table;
631                 }
632                 /*
633                  * Mark the table to avoid being used in
634                  * acpi_table_initrd_scan() and check the revision.
635                  */
636                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
637                     existing_table->oem_revision >= table->oem_revision) {
638                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
639                         goto next_table;
640                 }
641
642                 *length = table_length;
643                 *address = acpi_tables_addr + table_offset;
644                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
645                         table->signature, table->oem_id,
646                         table->oem_table_id);
647                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
648                 break;
649
650 next_table:
651                 table_offset += table_length;
652                 table_index++;
653         }
654         return AE_OK;
655 }
656
657 static void __init acpi_table_initrd_scan(void)
658 {
659         int table_offset = 0;
660         int table_index = 0;
661         u32 table_length;
662         struct acpi_table_header *table;
663
664         if (!acpi_tables_addr)
665                 return;
666
667         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
668                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
669                                            ACPI_HEADER_SIZE);
670                 if (table_offset + table->length > all_tables_size) {
671                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
672                         WARN_ON(1);
673                         return;
674                 }
675
676                 table_length = table->length;
677
678                 /* Skip RSDT/XSDT which should only be used for override */
679                 if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
680                     ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
681                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
682                         goto next_table;
683                 }
684                 /*
685                  * Mark the table to avoid being used in
686                  * acpi_table_initrd_override(). Though this is not possible
687                  * because override is disabled in acpi_install_table().
688                  */
689                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
690                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
691                         goto next_table;
692                 }
693
694                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
695                         table->signature, table->oem_id,
696                         table->oem_table_id);
697                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
698                 acpi_install_table(acpi_tables_addr + table_offset, TRUE);
699 next_table:
700                 table_offset += table_length;
701                 table_index++;
702         }
703 }
704 #else
705 static acpi_status
706 acpi_table_initrd_override(struct acpi_table_header *existing_table,
707                            acpi_physical_address *address,
708                            u32 *table_length)
709 {
710         *table_length = 0;
711         *address = 0;
712         return AE_OK;
713 }
714
715 static void __init acpi_table_initrd_scan(void)
716 {
717 }
718 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
719
720 acpi_status
721 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
722                                 acpi_physical_address *address,
723                                 u32 *table_length)
724 {
725         return acpi_table_initrd_override(existing_table, address,
726                                           table_length);
727 }
728
729 acpi_status
730 acpi_os_table_override(struct acpi_table_header *existing_table,
731                        struct acpi_table_header **new_table)
732 {
733         if (!existing_table || !new_table)
734                 return AE_BAD_PARAMETER;
735
736         *new_table = NULL;
737
738 #ifdef CONFIG_ACPI_CUSTOM_DSDT
739         if (strncmp(existing_table->signature, "DSDT", 4) == 0)
740                 *new_table = (struct acpi_table_header *)AmlCode;
741 #endif
742         if (*new_table != NULL)
743                 acpi_table_taint(existing_table);
744         return AE_OK;
745 }
746
747 /*
748  * acpi_table_init()
749  *
750  * find RSDP, find and checksum SDT/XSDT.
751  * checksum all tables, print SDT/XSDT
752  *
753  * result: sdt_entry[] is initialized
754  */
755
756 int __init acpi_table_init(void)
757 {
758         acpi_status status;
759
760         if (acpi_verify_table_checksum) {
761                 pr_info("Early table checksum verification enabled\n");
762                 acpi_gbl_verify_table_checksum = TRUE;
763         } else {
764                 pr_info("Early table checksum verification disabled\n");
765                 acpi_gbl_verify_table_checksum = FALSE;
766         }
767
768         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
769         if (ACPI_FAILURE(status))
770                 return -EINVAL;
771         acpi_table_initrd_scan();
772
773         check_multiple_madt();
774         return 0;
775 }
776
777 static int __init acpi_parse_apic_instance(char *str)
778 {
779         if (!str)
780                 return -EINVAL;
781
782         if (kstrtoint(str, 0, &acpi_apic_instance))
783                 return -EINVAL;
784
785         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
786
787         return 0;
788 }
789
790 early_param("acpi_apic_instance", acpi_parse_apic_instance);
791
792 static int __init acpi_force_table_verification_setup(char *s)
793 {
794         acpi_verify_table_checksum = true;
795
796         return 0;
797 }
798
799 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
800
801 static int __init acpi_force_32bit_fadt_addr(char *s)
802 {
803         pr_info("Forcing 32 Bit FADT addresses\n");
804         acpi_gbl_use32_bit_fadt_addresses = TRUE;
805
806         return 0;
807 }
808
809 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);