ACPI / EC: Work around method reentrancy limit in ACPICA for _Qxx
[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 "internal.h"
38
39 #ifdef CONFIG_ACPI_CUSTOM_DSDT
40 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
41 #endif
42
43 #define ACPI_MAX_TABLES         128
44
45 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
46 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
47
48 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
49
50 static int acpi_apic_instance __initdata;
51
52 /*
53  * Disable table checksum verification for the early stage due to the size
54  * limitation of the current x86 early mapping implementation.
55  */
56 static bool acpi_verify_table_checksum __initdata = false;
57
58 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
59 {
60         if (!header)
61                 return;
62
63         switch (header->type) {
64
65         case ACPI_MADT_TYPE_LOCAL_APIC:
66                 {
67                         struct acpi_madt_local_apic *p =
68                             (struct acpi_madt_local_apic *)header;
69                         pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
70                                  p->processor_id, p->id,
71                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
72                 }
73                 break;
74
75         case ACPI_MADT_TYPE_LOCAL_X2APIC:
76                 {
77                         struct acpi_madt_local_x2apic *p =
78                             (struct acpi_madt_local_x2apic *)header;
79                         pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
80                                  p->local_apic_id, p->uid,
81                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
82                 }
83                 break;
84
85         case ACPI_MADT_TYPE_IO_APIC:
86                 {
87                         struct acpi_madt_io_apic *p =
88                             (struct acpi_madt_io_apic *)header;
89                         pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
90                                  p->id, p->address, p->global_irq_base);
91                 }
92                 break;
93
94         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
95                 {
96                         struct acpi_madt_interrupt_override *p =
97                             (struct acpi_madt_interrupt_override *)header;
98                         pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
99                                 p->bus, p->source_irq, p->global_irq,
100                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
101                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
102                         if (p->inti_flags  &
103                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
104                                 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
105                                         p->inti_flags  &
106                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
107                 }
108                 break;
109
110         case ACPI_MADT_TYPE_NMI_SOURCE:
111                 {
112                         struct acpi_madt_nmi_source *p =
113                             (struct acpi_madt_nmi_source *)header;
114                         pr_info("NMI_SRC (%s %s global_irq %d)\n",
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->global_irq);
118                 }
119                 break;
120
121         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
122                 {
123                         struct acpi_madt_local_apic_nmi *p =
124                             (struct acpi_madt_local_apic_nmi *)header;
125                         pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
126                                 p->processor_id,
127                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
128                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
129                                 p->lint);
130                 }
131                 break;
132
133         case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
134                 {
135                         u16 polarity, trigger;
136                         struct acpi_madt_local_x2apic_nmi *p =
137                             (struct acpi_madt_local_x2apic_nmi *)header;
138
139                         polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
140                         trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
141
142                         pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
143                                 p->uid,
144                                 mps_inti_flags_polarity[polarity],
145                                 mps_inti_flags_trigger[trigger],
146                                 p->lint);
147                 }
148                 break;
149
150         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
151                 {
152                         struct acpi_madt_local_apic_override *p =
153                             (struct acpi_madt_local_apic_override *)header;
154                         pr_info("LAPIC_ADDR_OVR (address[%p])\n",
155                                 (void *)(unsigned long)p->address);
156                 }
157                 break;
158
159         case ACPI_MADT_TYPE_IO_SAPIC:
160                 {
161                         struct acpi_madt_io_sapic *p =
162                             (struct acpi_madt_io_sapic *)header;
163                         pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
164                                  p->id, (void *)(unsigned long)p->address,
165                                  p->global_irq_base);
166                 }
167                 break;
168
169         case ACPI_MADT_TYPE_LOCAL_SAPIC:
170                 {
171                         struct acpi_madt_local_sapic *p =
172                             (struct acpi_madt_local_sapic *)header;
173                         pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
174                                  p->processor_id, p->id, p->eid,
175                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
176                 }
177                 break;
178
179         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
180                 {
181                         struct acpi_madt_interrupt_source *p =
182                             (struct acpi_madt_interrupt_source *)header;
183                         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",
184                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
185                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
186                                 p->type, p->id, p->eid, p->io_sapic_vector,
187                                 p->global_irq);
188                 }
189                 break;
190
191         case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
192                 {
193                         struct acpi_madt_generic_interrupt *p =
194                                 (struct acpi_madt_generic_interrupt *)header;
195                         pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
196                                  p->uid, p->base_address,
197                                  p->arm_mpidr,
198                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
199
200                 }
201                 break;
202
203         case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
204                 {
205                         struct acpi_madt_generic_distributor *p =
206                                 (struct acpi_madt_generic_distributor *)header;
207                         pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
208                                  p->gic_id, p->base_address,
209                                  p->global_irq_base);
210                 }
211                 break;
212
213         default:
214                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
215                         header->type);
216                 break;
217         }
218 }
219
220 /**
221  * acpi_parse_entries_array - for each proc_num find a suitable subtable
222  *
223  * @id: table id (for debugging purposes)
224  * @table_size: single entry size
225  * @table_header: where does the table start?
226  * @proc: array of acpi_subtable_proc struct containing entry id
227  *        and associated handler with it
228  * @proc_num: how big proc is?
229  * @max_entries: how many entries can we process?
230  *
231  * For each proc_num find a subtable with proc->id and run proc->handler
232  * on it. Assumption is that there's only single handler for particular
233  * entry id.
234  *
235  * On success returns sum of all matching entries for all proc handlers.
236  * Otherwise, -ENODEV or -EINVAL is returned.
237  */
238 static int __init
239 acpi_parse_entries_array(char *id, unsigned long table_size,
240                 struct acpi_table_header *table_header,
241                 struct acpi_subtable_proc *proc, int proc_num,
242                 unsigned int max_entries)
243 {
244         struct acpi_subtable_header *entry;
245         unsigned long table_end;
246         int count = 0;
247         int i;
248
249         if (acpi_disabled)
250                 return -ENODEV;
251
252         if (!id)
253                 return -EINVAL;
254
255         if (!table_size)
256                 return -EINVAL;
257
258         if (!table_header) {
259                 pr_warn("%4.4s not present\n", id);
260                 return -ENODEV;
261         }
262
263         table_end = (unsigned long)table_header + table_header->length;
264
265         /* Parse all entries looking for a match. */
266
267         entry = (struct acpi_subtable_header *)
268             ((unsigned long)table_header + table_size);
269
270         while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
271                table_end) {
272                 if (max_entries && count >= max_entries)
273                         break;
274
275                 for (i = 0; i < proc_num; i++) {
276                         if (entry->type != proc[i].id)
277                                 continue;
278                         if (!proc[i].handler ||
279                              proc[i].handler(entry, table_end))
280                                 return -EINVAL;
281
282                         proc->count++;
283                         break;
284                 }
285                 if (i != proc_num)
286                         count++;
287
288                 /*
289                  * If entry->length is 0, break from this loop to avoid
290                  * infinite loop.
291                  */
292                 if (entry->length == 0) {
293                         pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
294                         return -EINVAL;
295                 }
296
297                 entry = (struct acpi_subtable_header *)
298                     ((unsigned long)entry + entry->length);
299         }
300
301         if (max_entries && count > max_entries) {
302                 pr_warn("[%4.4s:0x%02x] ignored %i entries of %i found\n",
303                         id, proc->id, count - max_entries, count);
304         }
305
306         return count;
307 }
308
309 int __init
310 acpi_parse_entries(char *id,
311                         unsigned long table_size,
312                         acpi_tbl_entry_handler handler,
313                         struct acpi_table_header *table_header,
314                         int entry_id, unsigned int max_entries)
315 {
316         struct acpi_subtable_proc proc = {
317                 .id             = entry_id,
318                 .handler        = handler,
319         };
320
321         return acpi_parse_entries_array(id, table_size, table_header,
322                         &proc, 1, max_entries);
323 }
324
325 int __init
326 acpi_table_parse_entries_array(char *id,
327                          unsigned long table_size,
328                          struct acpi_subtable_proc *proc, int proc_num,
329                          unsigned int max_entries)
330 {
331         struct acpi_table_header *table_header = NULL;
332         acpi_size tbl_size;
333         int count;
334         u32 instance = 0;
335
336         if (acpi_disabled)
337                 return -ENODEV;
338
339         if (!id)
340                 return -EINVAL;
341
342         if (!strncmp(id, ACPI_SIG_MADT, 4))
343                 instance = acpi_apic_instance;
344
345         acpi_get_table_with_size(id, instance, &table_header, &tbl_size);
346         if (!table_header) {
347                 pr_warn("%4.4s not present\n", id);
348                 return -ENODEV;
349         }
350
351         count = acpi_parse_entries_array(id, table_size, table_header,
352                         proc, proc_num, max_entries);
353
354         early_acpi_os_unmap_memory((char *)table_header, tbl_size);
355         return count;
356 }
357
358 int __init
359 acpi_table_parse_entries(char *id,
360                         unsigned long table_size,
361                         int entry_id,
362                         acpi_tbl_entry_handler handler,
363                         unsigned int max_entries)
364 {
365         struct acpi_subtable_proc proc = {
366                 .id             = entry_id,
367                 .handler        = handler,
368         };
369
370         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
371                                                 max_entries);
372 }
373
374 int __init
375 acpi_table_parse_madt(enum acpi_madt_type id,
376                       acpi_tbl_entry_handler handler, unsigned int max_entries)
377 {
378         return acpi_table_parse_entries(ACPI_SIG_MADT,
379                                             sizeof(struct acpi_table_madt), id,
380                                             handler, max_entries);
381 }
382
383 /**
384  * acpi_table_parse - find table with @id, run @handler on it
385  * @id: table id to find
386  * @handler: handler to run
387  *
388  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
389  * run @handler on it.
390  *
391  * Return 0 if table found, -errno if not.
392  */
393 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
394 {
395         struct acpi_table_header *table = NULL;
396         acpi_size tbl_size;
397
398         if (acpi_disabled)
399                 return -ENODEV;
400
401         if (!id || !handler)
402                 return -EINVAL;
403
404         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
405                 acpi_get_table_with_size(id, acpi_apic_instance, &table, &tbl_size);
406         else
407                 acpi_get_table_with_size(id, 0, &table, &tbl_size);
408
409         if (table) {
410                 handler(table);
411                 early_acpi_os_unmap_memory(table, tbl_size);
412                 return 0;
413         } else
414                 return -ENODEV;
415 }
416
417 /* 
418  * The BIOS is supposed to supply a single APIC/MADT,
419  * but some report two.  Provide a knob to use either.
420  * (don't you wish instance 0 and 1 were not the same?)
421  */
422 static void __init check_multiple_madt(void)
423 {
424         struct acpi_table_header *table = NULL;
425         acpi_size tbl_size;
426
427         acpi_get_table_with_size(ACPI_SIG_MADT, 2, &table, &tbl_size);
428         if (table) {
429                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
430                         acpi_apic_instance);
431                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
432                         "notify linux-acpi@vger.kernel.org\n",
433                         acpi_apic_instance ? 0 : 2);
434                 early_acpi_os_unmap_memory(table, tbl_size);
435
436         } else
437                 acpi_apic_instance = 0;
438
439         return;
440 }
441
442 static void acpi_table_taint(struct acpi_table_header *table)
443 {
444         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
445                 table->signature, table->oem_table_id);
446         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
447 }
448
449 #ifdef CONFIG_ACPI_TABLE_UPGRADE
450 static u64 acpi_tables_addr;
451 static int all_tables_size;
452
453 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
454 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
455 {
456         u8 sum = 0;
457         u8 *end = buffer + length;
458
459         while (buffer < end)
460                 sum = (u8) (sum + *(buffer++));
461         return sum;
462 }
463
464 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
465 static const char * const table_sigs[] = {
466         ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
467         ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
468         ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
469         ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
470         ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
471         ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
472         ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
473         ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
474         ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, NULL };
475
476 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
477
478 #define NR_ACPI_INITRD_TABLES 64
479 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
480 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
481
482 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
483
484 static void __init acpi_table_initrd_init(void *data, size_t size)
485 {
486         int sig, no, table_nr = 0, total_offset = 0;
487         long offset = 0;
488         struct acpi_table_header *table;
489         char cpio_path[32] = "kernel/firmware/acpi/";
490         struct cpio_data file;
491
492         if (data == NULL || size == 0)
493                 return;
494
495         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
496                 file = find_cpio_data(cpio_path, data, size, &offset);
497                 if (!file.data)
498                         break;
499
500                 data += offset;
501                 size -= offset;
502
503                 if (file.size < sizeof(struct acpi_table_header)) {
504                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
505                                 cpio_path, file.name);
506                         continue;
507                 }
508
509                 table = file.data;
510
511                 for (sig = 0; table_sigs[sig]; sig++)
512                         if (!memcmp(table->signature, table_sigs[sig], 4))
513                                 break;
514
515                 if (!table_sigs[sig]) {
516                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
517                                 cpio_path, file.name);
518                         continue;
519                 }
520                 if (file.size != table->length) {
521                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
522                                 cpio_path, file.name);
523                         continue;
524                 }
525                 if (acpi_table_checksum(file.data, table->length)) {
526                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
527                                 cpio_path, file.name);
528                         continue;
529                 }
530
531                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
532                         table->signature, cpio_path, file.name, table->length);
533
534                 all_tables_size += table->length;
535                 acpi_initrd_files[table_nr].data = file.data;
536                 acpi_initrd_files[table_nr].size = file.size;
537                 table_nr++;
538         }
539         if (table_nr == 0)
540                 return;
541
542         acpi_tables_addr =
543                 memblock_find_in_range(0, max_low_pfn_mapped << PAGE_SHIFT,
544                                        all_tables_size, PAGE_SIZE);
545         if (!acpi_tables_addr) {
546                 WARN_ON(1);
547                 return;
548         }
549         /*
550          * Only calling e820_add_reserve does not work and the
551          * tables are invalid (memory got used) later.
552          * memblock_reserve works as expected and the tables won't get modified.
553          * But it's not enough on X86 because ioremap will
554          * complain later (used by acpi_os_map_memory) that the pages
555          * that should get mapped are not marked "reserved".
556          * Both memblock_reserve and e820_add_region (via arch_reserve_mem_area)
557          * works fine.
558          */
559         memblock_reserve(acpi_tables_addr, all_tables_size);
560         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
561
562         /*
563          * early_ioremap only can remap 256k one time. If we map all
564          * tables one time, we will hit the limit. Need to map chunks
565          * one by one during copying the same as that in relocate_initrd().
566          */
567         for (no = 0; no < table_nr; no++) {
568                 unsigned char *src_p = acpi_initrd_files[no].data;
569                 phys_addr_t size = acpi_initrd_files[no].size;
570                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
571                 phys_addr_t slop, clen;
572                 char *dest_p;
573
574                 total_offset += size;
575
576                 while (size) {
577                         slop = dest_addr & ~PAGE_MASK;
578                         clen = size;
579                         if (clen > MAP_CHUNK_SIZE - slop)
580                                 clen = MAP_CHUNK_SIZE - slop;
581                         dest_p = early_ioremap(dest_addr & PAGE_MASK,
582                                                  clen + slop);
583                         memcpy(dest_p + slop, src_p, clen);
584                         early_iounmap(dest_p, clen + slop);
585                         src_p += clen;
586                         dest_addr += clen;
587                         size -= clen;
588                 }
589         }
590 }
591
592 static acpi_status
593 acpi_table_initrd_override(struct acpi_table_header *existing_table,
594                            acpi_physical_address *address, u32 *length)
595 {
596         int table_offset = 0;
597         int table_index = 0;
598         struct acpi_table_header *table;
599         u32 table_length;
600
601         *length = 0;
602         *address = 0;
603         if (!acpi_tables_addr)
604                 return AE_OK;
605
606         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
607                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
608                                            ACPI_HEADER_SIZE);
609                 if (table_offset + table->length > all_tables_size) {
610                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
611                         WARN_ON(1);
612                         return AE_OK;
613                 }
614
615                 table_length = table->length;
616
617                 /* Only override tables matched */
618                 if (memcmp(existing_table->signature, table->signature, 4) ||
619                     memcmp(table->oem_id, existing_table->oem_id,
620                            ACPI_OEM_ID_SIZE) ||
621                     memcmp(table->oem_table_id, existing_table->oem_table_id,
622                            ACPI_OEM_TABLE_ID_SIZE)) {
623                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
624                         goto next_table;
625                 }
626                 /*
627                  * Mark the table to avoid being used in
628                  * acpi_table_initrd_scan() and check the revision.
629                  */
630                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
631                     existing_table->oem_revision >= table->oem_revision) {
632                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
633                         goto next_table;
634                 }
635
636                 *length = table_length;
637                 *address = acpi_tables_addr + table_offset;
638                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
639                         table->signature, table->oem_id,
640                         table->oem_table_id);
641                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
642                 break;
643
644 next_table:
645                 table_offset += table_length;
646                 table_index++;
647         }
648         return AE_OK;
649 }
650
651 static void __init acpi_table_initrd_scan(void)
652 {
653         int table_offset = 0;
654         int table_index = 0;
655         u32 table_length;
656         struct acpi_table_header *table;
657
658         if (!acpi_tables_addr)
659                 return;
660
661         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
662                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
663                                            ACPI_HEADER_SIZE);
664                 if (table_offset + table->length > all_tables_size) {
665                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
666                         WARN_ON(1);
667                         return;
668                 }
669
670                 table_length = table->length;
671
672                 /* Skip RSDT/XSDT which should only be used for override */
673                 if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
674                     ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
675                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
676                         goto next_table;
677                 }
678                 /*
679                  * Mark the table to avoid being used in
680                  * acpi_table_initrd_override(). Though this is not possible
681                  * because override is disabled in acpi_install_table().
682                  */
683                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
684                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
685                         goto next_table;
686                 }
687
688                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
689                         table->signature, table->oem_id,
690                         table->oem_table_id);
691                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
692                 acpi_install_table(acpi_tables_addr + table_offset, TRUE);
693 next_table:
694                 table_offset += table_length;
695                 table_index++;
696         }
697 }
698 #else
699 static void __init acpi_table_initrd_init(void *data, size_t size)
700 {
701 }
702
703 static acpi_status
704 acpi_table_initrd_override(struct acpi_table_header *existing_table,
705                            acpi_physical_address *address,
706                            u32 *table_length)
707 {
708         *table_length = 0;
709         *address = 0;
710         return AE_OK;
711 }
712
713 static void __init acpi_table_initrd_scan(void)
714 {
715 }
716 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
717
718 acpi_status
719 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
720                                 acpi_physical_address *address,
721                                 u32 *table_length)
722 {
723         return acpi_table_initrd_override(existing_table, address,
724                                           table_length);
725 }
726
727 acpi_status
728 acpi_os_table_override(struct acpi_table_header *existing_table,
729                        struct acpi_table_header **new_table)
730 {
731         if (!existing_table || !new_table)
732                 return AE_BAD_PARAMETER;
733
734         *new_table = NULL;
735
736 #ifdef CONFIG_ACPI_CUSTOM_DSDT
737         if (strncmp(existing_table->signature, "DSDT", 4) == 0)
738                 *new_table = (struct acpi_table_header *)AmlCode;
739 #endif
740         if (*new_table != NULL)
741                 acpi_table_taint(existing_table);
742         return AE_OK;
743 }
744
745 void __init early_acpi_table_init(void *data, size_t size)
746 {
747         acpi_table_initrd_init(data, size);
748 }
749
750 /*
751  * acpi_table_init()
752  *
753  * find RSDP, find and checksum SDT/XSDT.
754  * checksum all tables, print SDT/XSDT
755  *
756  * result: sdt_entry[] is initialized
757  */
758
759 int __init acpi_table_init(void)
760 {
761         acpi_status status;
762
763         if (acpi_verify_table_checksum) {
764                 pr_info("Early table checksum verification enabled\n");
765                 acpi_gbl_verify_table_checksum = TRUE;
766         } else {
767                 pr_info("Early table checksum verification disabled\n");
768                 acpi_gbl_verify_table_checksum = FALSE;
769         }
770
771         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
772         if (ACPI_FAILURE(status))
773                 return -EINVAL;
774         acpi_table_initrd_scan();
775
776         check_multiple_madt();
777         return 0;
778 }
779
780 static int __init acpi_parse_apic_instance(char *str)
781 {
782         if (!str)
783                 return -EINVAL;
784
785         if (kstrtoint(str, 0, &acpi_apic_instance))
786                 return -EINVAL;
787
788         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
789
790         return 0;
791 }
792
793 early_param("acpi_apic_instance", acpi_parse_apic_instance);
794
795 static int __init acpi_force_table_verification_setup(char *s)
796 {
797         acpi_verify_table_checksum = true;
798
799         return 0;
800 }
801
802 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
803
804 static int __init acpi_force_32bit_fadt_addr(char *s)
805 {
806         pr_info("Forcing 32 Bit FADT addresses\n");
807         acpi_gbl_use32_bit_fadt_addresses = TRUE;
808
809         return 0;
810 }
811
812 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);