]> asedeno.scripts.mit.edu Git - linux.git/blob - drivers/acpi/tables.c
acpi: Disable ACPI table override if the kernel is locked down
[linux.git] / drivers / acpi / tables.c
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 "internal.h"
25
26 #ifdef CONFIG_ACPI_CUSTOM_DSDT
27 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
28 #endif
29
30 #define ACPI_MAX_TABLES         128
31
32 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
33 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
34
35 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
36
37 static int acpi_apic_instance __initdata;
38
39 enum acpi_subtable_type {
40         ACPI_SUBTABLE_COMMON,
41         ACPI_SUBTABLE_HMAT,
42 };
43
44 struct acpi_subtable_entry {
45         union acpi_subtable_headers *hdr;
46         enum acpi_subtable_type type;
47 };
48
49 /*
50  * Disable table checksum verification for the early stage due to the size
51  * limitation of the current x86 early mapping implementation.
52  */
53 static bool acpi_verify_table_checksum __initdata = false;
54
55 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
56 {
57         if (!header)
58                 return;
59
60         switch (header->type) {
61
62         case ACPI_MADT_TYPE_LOCAL_APIC:
63                 {
64                         struct acpi_madt_local_apic *p =
65                             (struct acpi_madt_local_apic *)header;
66                         pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
67                                  p->processor_id, p->id,
68                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
69                 }
70                 break;
71
72         case ACPI_MADT_TYPE_LOCAL_X2APIC:
73                 {
74                         struct acpi_madt_local_x2apic *p =
75                             (struct acpi_madt_local_x2apic *)header;
76                         pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
77                                  p->local_apic_id, p->uid,
78                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
79                 }
80                 break;
81
82         case ACPI_MADT_TYPE_IO_APIC:
83                 {
84                         struct acpi_madt_io_apic *p =
85                             (struct acpi_madt_io_apic *)header;
86                         pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
87                                  p->id, p->address, p->global_irq_base);
88                 }
89                 break;
90
91         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
92                 {
93                         struct acpi_madt_interrupt_override *p =
94                             (struct acpi_madt_interrupt_override *)header;
95                         pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
96                                 p->bus, p->source_irq, p->global_irq,
97                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
98                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
99                         if (p->inti_flags  &
100                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
101                                 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
102                                         p->inti_flags  &
103                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
104                 }
105                 break;
106
107         case ACPI_MADT_TYPE_NMI_SOURCE:
108                 {
109                         struct acpi_madt_nmi_source *p =
110                             (struct acpi_madt_nmi_source *)header;
111                         pr_info("NMI_SRC (%s %s global_irq %d)\n",
112                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
113                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
114                                 p->global_irq);
115                 }
116                 break;
117
118         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
119                 {
120                         struct acpi_madt_local_apic_nmi *p =
121                             (struct acpi_madt_local_apic_nmi *)header;
122                         pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
123                                 p->processor_id,
124                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
125                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
126                                 p->lint);
127                 }
128                 break;
129
130         case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
131                 {
132                         u16 polarity, trigger;
133                         struct acpi_madt_local_x2apic_nmi *p =
134                             (struct acpi_madt_local_x2apic_nmi *)header;
135
136                         polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
137                         trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
138
139                         pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
140                                 p->uid,
141                                 mps_inti_flags_polarity[polarity],
142                                 mps_inti_flags_trigger[trigger],
143                                 p->lint);
144                 }
145                 break;
146
147         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
148                 {
149                         struct acpi_madt_local_apic_override *p =
150                             (struct acpi_madt_local_apic_override *)header;
151                         pr_info("LAPIC_ADDR_OVR (address[%p])\n",
152                                 (void *)(unsigned long)p->address);
153                 }
154                 break;
155
156         case ACPI_MADT_TYPE_IO_SAPIC:
157                 {
158                         struct acpi_madt_io_sapic *p =
159                             (struct acpi_madt_io_sapic *)header;
160                         pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
161                                  p->id, (void *)(unsigned long)p->address,
162                                  p->global_irq_base);
163                 }
164                 break;
165
166         case ACPI_MADT_TYPE_LOCAL_SAPIC:
167                 {
168                         struct acpi_madt_local_sapic *p =
169                             (struct acpi_madt_local_sapic *)header;
170                         pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
171                                  p->processor_id, p->id, p->eid,
172                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
173                 }
174                 break;
175
176         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
177                 {
178                         struct acpi_madt_interrupt_source *p =
179                             (struct acpi_madt_interrupt_source *)header;
180                         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",
181                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
182                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
183                                 p->type, p->id, p->eid, p->io_sapic_vector,
184                                 p->global_irq);
185                 }
186                 break;
187
188         case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
189                 {
190                         struct acpi_madt_generic_interrupt *p =
191                                 (struct acpi_madt_generic_interrupt *)header;
192                         pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
193                                  p->uid, p->base_address,
194                                  p->arm_mpidr,
195                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
196
197                 }
198                 break;
199
200         case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
201                 {
202                         struct acpi_madt_generic_distributor *p =
203                                 (struct acpi_madt_generic_distributor *)header;
204                         pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
205                                  p->gic_id, p->base_address,
206                                  p->global_irq_base);
207                 }
208                 break;
209
210         default:
211                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
212                         header->type);
213                 break;
214         }
215 }
216
217 static unsigned long __init
218 acpi_get_entry_type(struct acpi_subtable_entry *entry)
219 {
220         switch (entry->type) {
221         case ACPI_SUBTABLE_COMMON:
222                 return entry->hdr->common.type;
223         case ACPI_SUBTABLE_HMAT:
224                 return entry->hdr->hmat.type;
225         }
226         return 0;
227 }
228
229 static unsigned long __init
230 acpi_get_entry_length(struct acpi_subtable_entry *entry)
231 {
232         switch (entry->type) {
233         case ACPI_SUBTABLE_COMMON:
234                 return entry->hdr->common.length;
235         case ACPI_SUBTABLE_HMAT:
236                 return entry->hdr->hmat.length;
237         }
238         return 0;
239 }
240
241 static unsigned long __init
242 acpi_get_subtable_header_length(struct acpi_subtable_entry *entry)
243 {
244         switch (entry->type) {
245         case ACPI_SUBTABLE_COMMON:
246                 return sizeof(entry->hdr->common);
247         case ACPI_SUBTABLE_HMAT:
248                 return sizeof(entry->hdr->hmat);
249         }
250         return 0;
251 }
252
253 static enum acpi_subtable_type __init
254 acpi_get_subtable_type(char *id)
255 {
256         if (strncmp(id, ACPI_SIG_HMAT, 4) == 0)
257                 return ACPI_SUBTABLE_HMAT;
258         return ACPI_SUBTABLE_COMMON;
259 }
260
261 /**
262  * acpi_parse_entries_array - for each proc_num find a suitable subtable
263  *
264  * @id: table id (for debugging purposes)
265  * @table_size: size of the root table
266  * @table_header: where does the table start?
267  * @proc: array of acpi_subtable_proc struct containing entry id
268  *        and associated handler with it
269  * @proc_num: how big proc is?
270  * @max_entries: how many entries can we process?
271  *
272  * For each proc_num find a subtable with proc->id and run proc->handler
273  * on it. Assumption is that there's only single handler for particular
274  * entry id.
275  *
276  * The table_size is not the size of the complete ACPI table (the length
277  * field in the header struct), but only the size of the root table; i.e.,
278  * the offset from the very first byte of the complete ACPI table, to the
279  * first byte of the very first subtable.
280  *
281  * On success returns sum of all matching entries for all proc handlers.
282  * Otherwise, -ENODEV or -EINVAL is returned.
283  */
284 static int __init acpi_parse_entries_array(char *id, unsigned long table_size,
285                 struct acpi_table_header *table_header,
286                 struct acpi_subtable_proc *proc, int proc_num,
287                 unsigned int max_entries)
288 {
289         struct acpi_subtable_entry entry;
290         unsigned long table_end, subtable_len, entry_len;
291         int count = 0;
292         int errs = 0;
293         int i;
294
295         if (acpi_disabled)
296                 return -ENODEV;
297
298         if (!id)
299                 return -EINVAL;
300
301         if (!table_size)
302                 return -EINVAL;
303
304         if (!table_header) {
305                 pr_warn("%4.4s not present\n", id);
306                 return -ENODEV;
307         }
308
309         table_end = (unsigned long)table_header + table_header->length;
310
311         /* Parse all entries looking for a match. */
312
313         entry.type = acpi_get_subtable_type(id);
314         entry.hdr = (union acpi_subtable_headers *)
315             ((unsigned long)table_header + table_size);
316         subtable_len = acpi_get_subtable_header_length(&entry);
317
318         while (((unsigned long)entry.hdr) + subtable_len  < table_end) {
319                 if (max_entries && count >= max_entries)
320                         break;
321
322                 for (i = 0; i < proc_num; i++) {
323                         if (acpi_get_entry_type(&entry) != proc[i].id)
324                                 continue;
325                         if (!proc[i].handler ||
326                              (!errs && proc[i].handler(entry.hdr, table_end))) {
327                                 errs++;
328                                 continue;
329                         }
330
331                         proc[i].count++;
332                         break;
333                 }
334                 if (i != proc_num)
335                         count++;
336
337                 /*
338                  * If entry->length is 0, break from this loop to avoid
339                  * infinite loop.
340                  */
341                 entry_len = acpi_get_entry_length(&entry);
342                 if (entry_len == 0) {
343                         pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
344                         return -EINVAL;
345                 }
346
347                 entry.hdr = (union acpi_subtable_headers *)
348                     ((unsigned long)entry.hdr + entry_len);
349         }
350
351         if (max_entries && count > max_entries) {
352                 pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
353                         id, proc->id, count);
354         }
355
356         return errs ? -EINVAL : count;
357 }
358
359 int __init acpi_table_parse_entries_array(char *id,
360                          unsigned long table_size,
361                          struct acpi_subtable_proc *proc, int proc_num,
362                          unsigned int max_entries)
363 {
364         struct acpi_table_header *table_header = NULL;
365         int count;
366         u32 instance = 0;
367
368         if (acpi_disabled)
369                 return -ENODEV;
370
371         if (!id)
372                 return -EINVAL;
373
374         if (!strncmp(id, ACPI_SIG_MADT, 4))
375                 instance = acpi_apic_instance;
376
377         acpi_get_table(id, instance, &table_header);
378         if (!table_header) {
379                 pr_warn("%4.4s not present\n", id);
380                 return -ENODEV;
381         }
382
383         count = acpi_parse_entries_array(id, table_size, table_header,
384                         proc, proc_num, max_entries);
385
386         acpi_put_table(table_header);
387         return count;
388 }
389
390 int __init acpi_table_parse_entries(char *id,
391                         unsigned long table_size,
392                         int entry_id,
393                         acpi_tbl_entry_handler handler,
394                         unsigned int max_entries)
395 {
396         struct acpi_subtable_proc proc = {
397                 .id             = entry_id,
398                 .handler        = handler,
399         };
400
401         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
402                                                 max_entries);
403 }
404
405 int __init acpi_table_parse_madt(enum acpi_madt_type id,
406                       acpi_tbl_entry_handler handler, unsigned int max_entries)
407 {
408         return acpi_table_parse_entries(ACPI_SIG_MADT,
409                                             sizeof(struct acpi_table_madt), id,
410                                             handler, max_entries);
411 }
412
413 /**
414  * acpi_table_parse - find table with @id, run @handler on it
415  * @id: table id to find
416  * @handler: handler to run
417  *
418  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
419  * run @handler on it.
420  *
421  * Return 0 if table found, -errno if not.
422  */
423 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
424 {
425         struct acpi_table_header *table = NULL;
426
427         if (acpi_disabled)
428                 return -ENODEV;
429
430         if (!id || !handler)
431                 return -EINVAL;
432
433         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
434                 acpi_get_table(id, acpi_apic_instance, &table);
435         else
436                 acpi_get_table(id, 0, &table);
437
438         if (table) {
439                 handler(table);
440                 acpi_put_table(table);
441                 return 0;
442         } else
443                 return -ENODEV;
444 }
445
446 /*
447  * The BIOS is supposed to supply a single APIC/MADT,
448  * but some report two.  Provide a knob to use either.
449  * (don't you wish instance 0 and 1 were not the same?)
450  */
451 static void __init check_multiple_madt(void)
452 {
453         struct acpi_table_header *table = NULL;
454
455         acpi_get_table(ACPI_SIG_MADT, 2, &table);
456         if (table) {
457                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
458                         acpi_apic_instance);
459                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
460                         "notify linux-acpi@vger.kernel.org\n",
461                         acpi_apic_instance ? 0 : 2);
462                 acpi_put_table(table);
463
464         } else
465                 acpi_apic_instance = 0;
466
467         return;
468 }
469
470 static void acpi_table_taint(struct acpi_table_header *table)
471 {
472         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
473                 table->signature, table->oem_table_id);
474         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
475 }
476
477 #ifdef CONFIG_ACPI_TABLE_UPGRADE
478 static u64 acpi_tables_addr;
479 static int all_tables_size;
480
481 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
482 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
483 {
484         u8 sum = 0;
485         u8 *end = buffer + length;
486
487         while (buffer < end)
488                 sum = (u8) (sum + *(buffer++));
489         return sum;
490 }
491
492 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
493 static const char * const table_sigs[] = {
494         ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
495         ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
496         ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
497         ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
498         ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
499         ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
500         ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
501         ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
502         ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, ACPI_SIG_IORT,
503         ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT, NULL };
504
505 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
506
507 #define NR_ACPI_INITRD_TABLES 64
508 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
509 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
510
511 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
512
513 void __init acpi_table_upgrade(void)
514 {
515         void *data;
516         size_t size;
517         int sig, no, table_nr = 0, total_offset = 0;
518         long offset = 0;
519         struct acpi_table_header *table;
520         char cpio_path[32] = "kernel/firmware/acpi/";
521         struct cpio_data file;
522
523         if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
524                 data = __initramfs_start;
525                 size = __initramfs_size;
526         } else {
527                 data = (void *)initrd_start;
528                 size = initrd_end - initrd_start;
529         }
530
531         if (data == NULL || size == 0)
532                 return;
533
534         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
535                 file = find_cpio_data(cpio_path, data, size, &offset);
536                 if (!file.data)
537                         break;
538
539                 data += offset;
540                 size -= offset;
541
542                 if (file.size < sizeof(struct acpi_table_header)) {
543                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
544                                 cpio_path, file.name);
545                         continue;
546                 }
547
548                 table = file.data;
549
550                 for (sig = 0; table_sigs[sig]; sig++)
551                         if (!memcmp(table->signature, table_sigs[sig], 4))
552                                 break;
553
554                 if (!table_sigs[sig]) {
555                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
556                                 cpio_path, file.name);
557                         continue;
558                 }
559                 if (file.size != table->length) {
560                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
561                                 cpio_path, file.name);
562                         continue;
563                 }
564                 if (acpi_table_checksum(file.data, table->length)) {
565                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
566                                 cpio_path, file.name);
567                         continue;
568                 }
569
570                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
571                         table->signature, cpio_path, file.name, table->length);
572
573                 all_tables_size += table->length;
574                 acpi_initrd_files[table_nr].data = file.data;
575                 acpi_initrd_files[table_nr].size = file.size;
576                 table_nr++;
577         }
578         if (table_nr == 0)
579                 return;
580
581         if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
582                 pr_notice("kernel is locked down, ignoring table override\n");
583                 return;
584         }
585
586         acpi_tables_addr =
587                 memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
588                                        all_tables_size, PAGE_SIZE);
589         if (!acpi_tables_addr) {
590                 WARN_ON(1);
591                 return;
592         }
593         /*
594          * Only calling e820_add_reserve does not work and the
595          * tables are invalid (memory got used) later.
596          * memblock_reserve works as expected and the tables won't get modified.
597          * But it's not enough on X86 because ioremap will
598          * complain later (used by acpi_os_map_memory) that the pages
599          * that should get mapped are not marked "reserved".
600          * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
601          * works fine.
602          */
603         memblock_reserve(acpi_tables_addr, all_tables_size);
604         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
605
606         /*
607          * early_ioremap only can remap 256k one time. If we map all
608          * tables one time, we will hit the limit. Need to map chunks
609          * one by one during copying the same as that in relocate_initrd().
610          */
611         for (no = 0; no < table_nr; no++) {
612                 unsigned char *src_p = acpi_initrd_files[no].data;
613                 phys_addr_t size = acpi_initrd_files[no].size;
614                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
615                 phys_addr_t slop, clen;
616                 char *dest_p;
617
618                 total_offset += size;
619
620                 while (size) {
621                         slop = dest_addr & ~PAGE_MASK;
622                         clen = size;
623                         if (clen > MAP_CHUNK_SIZE - slop)
624                                 clen = MAP_CHUNK_SIZE - slop;
625                         dest_p = early_memremap(dest_addr & PAGE_MASK,
626                                                 clen + slop);
627                         memcpy(dest_p + slop, src_p, clen);
628                         early_memunmap(dest_p, clen + slop);
629                         src_p += clen;
630                         dest_addr += clen;
631                         size -= clen;
632                 }
633         }
634 }
635
636 static acpi_status
637 acpi_table_initrd_override(struct acpi_table_header *existing_table,
638                            acpi_physical_address *address, u32 *length)
639 {
640         int table_offset = 0;
641         int table_index = 0;
642         struct acpi_table_header *table;
643         u32 table_length;
644
645         *length = 0;
646         *address = 0;
647         if (!acpi_tables_addr)
648                 return AE_OK;
649
650         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
651                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
652                                            ACPI_HEADER_SIZE);
653                 if (table_offset + table->length > all_tables_size) {
654                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
655                         WARN_ON(1);
656                         return AE_OK;
657                 }
658
659                 table_length = table->length;
660
661                 /* Only override tables matched */
662                 if (memcmp(existing_table->signature, table->signature, 4) ||
663                     memcmp(table->oem_id, existing_table->oem_id,
664                            ACPI_OEM_ID_SIZE) ||
665                     memcmp(table->oem_table_id, existing_table->oem_table_id,
666                            ACPI_OEM_TABLE_ID_SIZE)) {
667                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
668                         goto next_table;
669                 }
670                 /*
671                  * Mark the table to avoid being used in
672                  * acpi_table_initrd_scan() and check the revision.
673                  */
674                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
675                     existing_table->oem_revision >= table->oem_revision) {
676                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
677                         goto next_table;
678                 }
679
680                 *length = table_length;
681                 *address = acpi_tables_addr + table_offset;
682                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
683                         table->signature, table->oem_id,
684                         table->oem_table_id);
685                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
686                 break;
687
688 next_table:
689                 table_offset += table_length;
690                 table_index++;
691         }
692         return AE_OK;
693 }
694
695 static void __init acpi_table_initrd_scan(void)
696 {
697         int table_offset = 0;
698         int table_index = 0;
699         u32 table_length;
700         struct acpi_table_header *table;
701
702         if (!acpi_tables_addr)
703                 return;
704
705         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
706                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
707                                            ACPI_HEADER_SIZE);
708                 if (table_offset + table->length > all_tables_size) {
709                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
710                         WARN_ON(1);
711                         return;
712                 }
713
714                 table_length = table->length;
715
716                 /* Skip RSDT/XSDT which should only be used for override */
717                 if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
718                     ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
719                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
720                         goto next_table;
721                 }
722                 /*
723                  * Mark the table to avoid being used in
724                  * acpi_table_initrd_override(). Though this is not possible
725                  * because override is disabled in acpi_install_table().
726                  */
727                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
728                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
729                         goto next_table;
730                 }
731
732                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
733                         table->signature, table->oem_id,
734                         table->oem_table_id);
735                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
736                 acpi_install_table(acpi_tables_addr + table_offset, TRUE);
737 next_table:
738                 table_offset += table_length;
739                 table_index++;
740         }
741 }
742 #else
743 static acpi_status
744 acpi_table_initrd_override(struct acpi_table_header *existing_table,
745                            acpi_physical_address *address,
746                            u32 *table_length)
747 {
748         *table_length = 0;
749         *address = 0;
750         return AE_OK;
751 }
752
753 static void __init acpi_table_initrd_scan(void)
754 {
755 }
756 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
757
758 acpi_status
759 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
760                                 acpi_physical_address *address,
761                                 u32 *table_length)
762 {
763         return acpi_table_initrd_override(existing_table, address,
764                                           table_length);
765 }
766
767 #ifdef CONFIG_ACPI_CUSTOM_DSDT
768 static void *amlcode __attribute__ ((weakref("AmlCode")));
769 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
770 #endif
771
772 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
773                        struct acpi_table_header **new_table)
774 {
775         if (!existing_table || !new_table)
776                 return AE_BAD_PARAMETER;
777
778         *new_table = NULL;
779
780 #ifdef CONFIG_ACPI_CUSTOM_DSDT
781         if (!strncmp(existing_table->signature, "DSDT", 4)) {
782                 *new_table = (struct acpi_table_header *)&amlcode;
783                 if (!(*new_table))
784                         *new_table = (struct acpi_table_header *)&dsdt_amlcode;
785         }
786 #endif
787         if (*new_table != NULL)
788                 acpi_table_taint(existing_table);
789         return AE_OK;
790 }
791
792 /*
793  * acpi_table_init()
794  *
795  * find RSDP, find and checksum SDT/XSDT.
796  * checksum all tables, print SDT/XSDT
797  *
798  * result: sdt_entry[] is initialized
799  */
800
801 int __init acpi_table_init(void)
802 {
803         acpi_status status;
804
805         if (acpi_verify_table_checksum) {
806                 pr_info("Early table checksum verification enabled\n");
807                 acpi_gbl_enable_table_validation = TRUE;
808         } else {
809                 pr_info("Early table checksum verification disabled\n");
810                 acpi_gbl_enable_table_validation = FALSE;
811         }
812
813         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
814         if (ACPI_FAILURE(status))
815                 return -EINVAL;
816         acpi_table_initrd_scan();
817
818         check_multiple_madt();
819         return 0;
820 }
821
822 static int __init acpi_parse_apic_instance(char *str)
823 {
824         if (!str)
825                 return -EINVAL;
826
827         if (kstrtoint(str, 0, &acpi_apic_instance))
828                 return -EINVAL;
829
830         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
831
832         return 0;
833 }
834 early_param("acpi_apic_instance", acpi_parse_apic_instance);
835
836 static int __init acpi_force_table_verification_setup(char *s)
837 {
838         acpi_verify_table_checksum = true;
839
840         return 0;
841 }
842 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
843
844 static int __init acpi_force_32bit_fadt_addr(char *s)
845 {
846         pr_info("Forcing 32 Bit FADT addresses\n");
847         acpi_gbl_use32_bit_fadt_addresses = TRUE;
848
849         return 0;
850 }
851 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);