xref: /openbmc/linux/drivers/acpi/tables.c (revision f71a261a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  acpi_tables.c - ACPI Boot-Time Table Parsing
4  *
5  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  */
7 
8 /* Uncomment next line to get verbose printout */
9 /* #define DEBUG */
10 #define pr_fmt(fmt) "ACPI: " fmt
11 
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/smp.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/irq.h>
18 #include <linux/errno.h>
19 #include <linux/acpi.h>
20 #include <linux/memblock.h>
21 #include <linux/earlycpio.h>
22 #include <linux/initrd.h>
23 #include <linux/security.h>
24 #include <linux/kmemleak.h>
25 #include "internal.h"
26 
27 #ifdef CONFIG_ACPI_CUSTOM_DSDT
28 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
29 #endif
30 
31 #define ACPI_MAX_TABLES		128
32 
33 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
34 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
35 
36 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
37 
38 static int acpi_apic_instance __initdata_or_acpilib;
39 
40 enum acpi_subtable_type {
41 	ACPI_SUBTABLE_COMMON,
42 	ACPI_SUBTABLE_HMAT,
43 	ACPI_SUBTABLE_PRMT,
44 	ACPI_SUBTABLE_CEDT,
45 };
46 
47 struct acpi_subtable_entry {
48 	union acpi_subtable_headers *hdr;
49 	enum acpi_subtable_type type;
50 };
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_or_acpilib = 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[0x%llx])\n",
155 				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 static unsigned long __init_or_acpilib
221 acpi_get_entry_type(struct acpi_subtable_entry *entry)
222 {
223 	switch (entry->type) {
224 	case ACPI_SUBTABLE_COMMON:
225 		return entry->hdr->common.type;
226 	case ACPI_SUBTABLE_HMAT:
227 		return entry->hdr->hmat.type;
228 	case ACPI_SUBTABLE_PRMT:
229 		return 0;
230 	case ACPI_SUBTABLE_CEDT:
231 		return entry->hdr->cedt.type;
232 	}
233 	return 0;
234 }
235 
236 static unsigned long __init_or_acpilib
237 acpi_get_entry_length(struct acpi_subtable_entry *entry)
238 {
239 	switch (entry->type) {
240 	case ACPI_SUBTABLE_COMMON:
241 		return entry->hdr->common.length;
242 	case ACPI_SUBTABLE_HMAT:
243 		return entry->hdr->hmat.length;
244 	case ACPI_SUBTABLE_PRMT:
245 		return entry->hdr->prmt.length;
246 	case ACPI_SUBTABLE_CEDT:
247 		return entry->hdr->cedt.length;
248 	}
249 	return 0;
250 }
251 
252 static unsigned long __init_or_acpilib
253 acpi_get_subtable_header_length(struct acpi_subtable_entry *entry)
254 {
255 	switch (entry->type) {
256 	case ACPI_SUBTABLE_COMMON:
257 		return sizeof(entry->hdr->common);
258 	case ACPI_SUBTABLE_HMAT:
259 		return sizeof(entry->hdr->hmat);
260 	case ACPI_SUBTABLE_PRMT:
261 		return sizeof(entry->hdr->prmt);
262 	case ACPI_SUBTABLE_CEDT:
263 		return sizeof(entry->hdr->cedt);
264 	}
265 	return 0;
266 }
267 
268 static enum acpi_subtable_type __init_or_acpilib
269 acpi_get_subtable_type(char *id)
270 {
271 	if (strncmp(id, ACPI_SIG_HMAT, 4) == 0)
272 		return ACPI_SUBTABLE_HMAT;
273 	if (strncmp(id, ACPI_SIG_PRMT, 4) == 0)
274 		return ACPI_SUBTABLE_PRMT;
275 	if (strncmp(id, ACPI_SIG_CEDT, 4) == 0)
276 		return ACPI_SUBTABLE_CEDT;
277 	return ACPI_SUBTABLE_COMMON;
278 }
279 
280 static __init_or_acpilib bool has_handler(struct acpi_subtable_proc *proc)
281 {
282 	return proc->handler || proc->handler_arg;
283 }
284 
285 static __init_or_acpilib int call_handler(struct acpi_subtable_proc *proc,
286 					  union acpi_subtable_headers *hdr,
287 					  unsigned long end)
288 {
289 	if (proc->handler)
290 		return proc->handler(hdr, end);
291 	if (proc->handler_arg)
292 		return proc->handler_arg(hdr, proc->arg, end);
293 	return -EINVAL;
294 }
295 
296 /**
297  * acpi_parse_entries_array - for each proc_num find a suitable subtable
298  *
299  * @id: table id (for debugging purposes)
300  * @table_size: size of the root table
301  * @table_header: where does the table start?
302  * @proc: array of acpi_subtable_proc struct containing entry id
303  *        and associated handler with it
304  * @proc_num: how big proc is?
305  * @max_entries: how many entries can we process?
306  *
307  * For each proc_num find a subtable with proc->id and run proc->handler
308  * on it. Assumption is that there's only single handler for particular
309  * entry id.
310  *
311  * The table_size is not the size of the complete ACPI table (the length
312  * field in the header struct), but only the size of the root table; i.e.,
313  * the offset from the very first byte of the complete ACPI table, to the
314  * first byte of the very first subtable.
315  *
316  * On success returns sum of all matching entries for all proc handlers.
317  * Otherwise, -ENODEV or -EINVAL is returned.
318  */
319 static int __init_or_acpilib acpi_parse_entries_array(
320 	char *id, unsigned long table_size,
321 	struct acpi_table_header *table_header, struct acpi_subtable_proc *proc,
322 	int proc_num, unsigned int max_entries)
323 {
324 	struct acpi_subtable_entry entry;
325 	unsigned long table_end, subtable_len, entry_len;
326 	int count = 0;
327 	int errs = 0;
328 	int i;
329 
330 	table_end = (unsigned long)table_header + table_header->length;
331 
332 	/* Parse all entries looking for a match. */
333 
334 	entry.type = acpi_get_subtable_type(id);
335 	entry.hdr = (union acpi_subtable_headers *)
336 	    ((unsigned long)table_header + table_size);
337 	subtable_len = acpi_get_subtable_header_length(&entry);
338 
339 	while (((unsigned long)entry.hdr) + subtable_len  < table_end) {
340 		if (max_entries && count >= max_entries)
341 			break;
342 
343 		for (i = 0; i < proc_num; i++) {
344 			if (acpi_get_entry_type(&entry) != proc[i].id)
345 				continue;
346 			if (!has_handler(&proc[i]) ||
347 			    (!errs &&
348 			     call_handler(&proc[i], entry.hdr, table_end))) {
349 				errs++;
350 				continue;
351 			}
352 
353 			proc[i].count++;
354 			break;
355 		}
356 		if (i != proc_num)
357 			count++;
358 
359 		/*
360 		 * If entry->length is 0, break from this loop to avoid
361 		 * infinite loop.
362 		 */
363 		entry_len = acpi_get_entry_length(&entry);
364 		if (entry_len == 0) {
365 			pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
366 			return -EINVAL;
367 		}
368 
369 		entry.hdr = (union acpi_subtable_headers *)
370 		    ((unsigned long)entry.hdr + entry_len);
371 	}
372 
373 	if (max_entries && count > max_entries) {
374 		pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
375 			id, proc->id, count);
376 	}
377 
378 	return errs ? -EINVAL : count;
379 }
380 
381 int __init_or_acpilib acpi_table_parse_entries_array(
382 	char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
383 	int proc_num, unsigned int max_entries)
384 {
385 	struct acpi_table_header *table_header = NULL;
386 	int count;
387 	u32 instance = 0;
388 
389 	if (acpi_disabled)
390 		return -ENODEV;
391 
392 	if (!id)
393 		return -EINVAL;
394 
395 	if (!table_size)
396 		return -EINVAL;
397 
398 	if (!strncmp(id, ACPI_SIG_MADT, 4))
399 		instance = acpi_apic_instance;
400 
401 	acpi_get_table(id, instance, &table_header);
402 	if (!table_header) {
403 		pr_debug("%4.4s not present\n", id);
404 		return -ENODEV;
405 	}
406 
407 	count = acpi_parse_entries_array(id, table_size, table_header,
408 			proc, proc_num, max_entries);
409 
410 	acpi_put_table(table_header);
411 	return count;
412 }
413 
414 static int __init_or_acpilib __acpi_table_parse_entries(
415 	char *id, unsigned long table_size, int entry_id,
416 	acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
417 	void *arg, unsigned int max_entries)
418 {
419 	struct acpi_subtable_proc proc = {
420 		.id		= entry_id,
421 		.handler	= handler,
422 		.handler_arg	= handler_arg,
423 		.arg		= arg,
424 	};
425 
426 	return acpi_table_parse_entries_array(id, table_size, &proc, 1,
427 						max_entries);
428 }
429 
430 int __init_or_acpilib
431 acpi_table_parse_cedt(enum acpi_cedt_type id,
432 		      acpi_tbl_entry_handler_arg handler_arg, void *arg)
433 {
434 	return __acpi_table_parse_entries(ACPI_SIG_CEDT,
435 					  sizeof(struct acpi_table_cedt), id,
436 					  NULL, handler_arg, arg, 0);
437 }
438 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
439 
440 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
441 				    int entry_id,
442 				    acpi_tbl_entry_handler handler,
443 				    unsigned int max_entries)
444 {
445 	return __acpi_table_parse_entries(id, table_size, entry_id, handler,
446 					  NULL, NULL, max_entries);
447 }
448 
449 int __init acpi_table_parse_madt(enum acpi_madt_type id,
450 		      acpi_tbl_entry_handler handler, unsigned int max_entries)
451 {
452 	return acpi_table_parse_entries(ACPI_SIG_MADT,
453 					    sizeof(struct acpi_table_madt), id,
454 					    handler, max_entries);
455 }
456 
457 /**
458  * acpi_table_parse - find table with @id, run @handler on it
459  * @id: table id to find
460  * @handler: handler to run
461  *
462  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
463  * run @handler on it.
464  *
465  * Return 0 if table found, -errno if not.
466  */
467 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
468 {
469 	struct acpi_table_header *table = NULL;
470 
471 	if (acpi_disabled)
472 		return -ENODEV;
473 
474 	if (!id || !handler)
475 		return -EINVAL;
476 
477 	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
478 		acpi_get_table(id, acpi_apic_instance, &table);
479 	else
480 		acpi_get_table(id, 0, &table);
481 
482 	if (table) {
483 		handler(table);
484 		acpi_put_table(table);
485 		return 0;
486 	} else
487 		return -ENODEV;
488 }
489 
490 /*
491  * The BIOS is supposed to supply a single APIC/MADT,
492  * but some report two.  Provide a knob to use either.
493  * (don't you wish instance 0 and 1 were not the same?)
494  */
495 static void __init check_multiple_madt(void)
496 {
497 	struct acpi_table_header *table = NULL;
498 
499 	acpi_get_table(ACPI_SIG_MADT, 2, &table);
500 	if (table) {
501 		pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
502 			acpi_apic_instance);
503 		pr_warn("If \"acpi_apic_instance=%d\" works better, "
504 			"notify linux-acpi@vger.kernel.org\n",
505 			acpi_apic_instance ? 0 : 2);
506 		acpi_put_table(table);
507 
508 	} else
509 		acpi_apic_instance = 0;
510 
511 	return;
512 }
513 
514 static void acpi_table_taint(struct acpi_table_header *table)
515 {
516 	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
517 		table->signature, table->oem_table_id);
518 	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
519 }
520 
521 #ifdef CONFIG_ACPI_TABLE_UPGRADE
522 static u64 acpi_tables_addr;
523 static int all_tables_size;
524 
525 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
526 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
527 {
528 	u8 sum = 0;
529 	u8 *end = buffer + length;
530 
531 	while (buffer < end)
532 		sum = (u8) (sum + *(buffer++));
533 	return sum;
534 }
535 
536 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
537 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
538 	ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
539 	ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
540 	ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
541 	ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
542 	ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
543 	ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
544 	ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
545 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
546 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
547 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
548 	ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI };
549 
550 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
551 
552 #define NR_ACPI_INITRD_TABLES 64
553 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
554 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
555 
556 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
557 
558 void __init acpi_table_upgrade(void)
559 {
560 	void *data;
561 	size_t size;
562 	int sig, no, table_nr = 0, total_offset = 0;
563 	long offset = 0;
564 	struct acpi_table_header *table;
565 	char cpio_path[32] = "kernel/firmware/acpi/";
566 	struct cpio_data file;
567 
568 	if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
569 		data = __initramfs_start;
570 		size = __initramfs_size;
571 	} else {
572 		data = (void *)initrd_start;
573 		size = initrd_end - initrd_start;
574 	}
575 
576 	if (data == NULL || size == 0)
577 		return;
578 
579 	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
580 		file = find_cpio_data(cpio_path, data, size, &offset);
581 		if (!file.data)
582 			break;
583 
584 		data += offset;
585 		size -= offset;
586 
587 		if (file.size < sizeof(struct acpi_table_header)) {
588 			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
589 				cpio_path, file.name);
590 			continue;
591 		}
592 
593 		table = file.data;
594 
595 		for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
596 			if (!memcmp(table->signature, table_sigs[sig], 4))
597 				break;
598 
599 		if (sig >= ARRAY_SIZE(table_sigs)) {
600 			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
601 				cpio_path, file.name);
602 			continue;
603 		}
604 		if (file.size != table->length) {
605 			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
606 				cpio_path, file.name);
607 			continue;
608 		}
609 		if (acpi_table_checksum(file.data, table->length)) {
610 			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
611 				cpio_path, file.name);
612 			continue;
613 		}
614 
615 		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
616 			table->signature, cpio_path, file.name, table->length);
617 
618 		all_tables_size += table->length;
619 		acpi_initrd_files[table_nr].data = file.data;
620 		acpi_initrd_files[table_nr].size = file.size;
621 		table_nr++;
622 	}
623 	if (table_nr == 0)
624 		return;
625 
626 	if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
627 		pr_notice("kernel is locked down, ignoring table override\n");
628 		return;
629 	}
630 
631 	acpi_tables_addr =
632 		memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
633 					  0, ACPI_TABLE_UPGRADE_MAX_PHYS);
634 	if (!acpi_tables_addr) {
635 		WARN_ON(1);
636 		return;
637 	}
638 	/*
639 	 * Only calling e820_add_reserve does not work and the
640 	 * tables are invalid (memory got used) later.
641 	 * memblock_reserve works as expected and the tables won't get modified.
642 	 * But it's not enough on X86 because ioremap will
643 	 * complain later (used by acpi_os_map_memory) that the pages
644 	 * that should get mapped are not marked "reserved".
645 	 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
646 	 * works fine.
647 	 */
648 	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
649 
650 	kmemleak_ignore_phys(acpi_tables_addr);
651 
652 	/*
653 	 * early_ioremap only can remap 256k one time. If we map all
654 	 * tables one time, we will hit the limit. Need to map chunks
655 	 * one by one during copying the same as that in relocate_initrd().
656 	 */
657 	for (no = 0; no < table_nr; no++) {
658 		unsigned char *src_p = acpi_initrd_files[no].data;
659 		phys_addr_t size = acpi_initrd_files[no].size;
660 		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
661 		phys_addr_t slop, clen;
662 		char *dest_p;
663 
664 		total_offset += size;
665 
666 		while (size) {
667 			slop = dest_addr & ~PAGE_MASK;
668 			clen = size;
669 			if (clen > MAP_CHUNK_SIZE - slop)
670 				clen = MAP_CHUNK_SIZE - slop;
671 			dest_p = early_memremap(dest_addr & PAGE_MASK,
672 						clen + slop);
673 			memcpy(dest_p + slop, src_p, clen);
674 			early_memunmap(dest_p, clen + slop);
675 			src_p += clen;
676 			dest_addr += clen;
677 			size -= clen;
678 		}
679 	}
680 }
681 
682 static acpi_status
683 acpi_table_initrd_override(struct acpi_table_header *existing_table,
684 			   acpi_physical_address *address, u32 *length)
685 {
686 	int table_offset = 0;
687 	int table_index = 0;
688 	struct acpi_table_header *table;
689 	u32 table_length;
690 
691 	*length = 0;
692 	*address = 0;
693 	if (!acpi_tables_addr)
694 		return AE_OK;
695 
696 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
697 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
698 					   ACPI_HEADER_SIZE);
699 		if (table_offset + table->length > all_tables_size) {
700 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
701 			WARN_ON(1);
702 			return AE_OK;
703 		}
704 
705 		table_length = table->length;
706 
707 		/* Only override tables matched */
708 		if (memcmp(existing_table->signature, table->signature, 4) ||
709 		    memcmp(table->oem_id, existing_table->oem_id,
710 			   ACPI_OEM_ID_SIZE) ||
711 		    memcmp(table->oem_table_id, existing_table->oem_table_id,
712 			   ACPI_OEM_TABLE_ID_SIZE)) {
713 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
714 			goto next_table;
715 		}
716 		/*
717 		 * Mark the table to avoid being used in
718 		 * acpi_table_initrd_scan() and check the revision.
719 		 */
720 		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
721 		    existing_table->oem_revision >= table->oem_revision) {
722 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
723 			goto next_table;
724 		}
725 
726 		*length = table_length;
727 		*address = acpi_tables_addr + table_offset;
728 		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
729 			table->signature, table->oem_id,
730 			table->oem_table_id);
731 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
732 		break;
733 
734 next_table:
735 		table_offset += table_length;
736 		table_index++;
737 	}
738 	return AE_OK;
739 }
740 
741 static void __init acpi_table_initrd_scan(void)
742 {
743 	int table_offset = 0;
744 	int table_index = 0;
745 	u32 table_length;
746 	struct acpi_table_header *table;
747 
748 	if (!acpi_tables_addr)
749 		return;
750 
751 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
752 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
753 					   ACPI_HEADER_SIZE);
754 		if (table_offset + table->length > all_tables_size) {
755 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
756 			WARN_ON(1);
757 			return;
758 		}
759 
760 		table_length = table->length;
761 
762 		/* Skip RSDT/XSDT which should only be used for override */
763 		if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
764 		    ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
765 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
766 			goto next_table;
767 		}
768 		/*
769 		 * Mark the table to avoid being used in
770 		 * acpi_table_initrd_override(). Though this is not possible
771 		 * because override is disabled in acpi_install_physical_table().
772 		 */
773 		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
774 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
775 			goto next_table;
776 		}
777 
778 		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
779 			table->signature, table->oem_id,
780 			table->oem_table_id);
781 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
782 		acpi_install_physical_table(acpi_tables_addr + table_offset);
783 next_table:
784 		table_offset += table_length;
785 		table_index++;
786 	}
787 }
788 #else
789 static acpi_status
790 acpi_table_initrd_override(struct acpi_table_header *existing_table,
791 			   acpi_physical_address *address,
792 			   u32 *table_length)
793 {
794 	*table_length = 0;
795 	*address = 0;
796 	return AE_OK;
797 }
798 
799 static void __init acpi_table_initrd_scan(void)
800 {
801 }
802 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
803 
804 acpi_status
805 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
806 				acpi_physical_address *address,
807 				u32 *table_length)
808 {
809 	return acpi_table_initrd_override(existing_table, address,
810 					  table_length);
811 }
812 
813 #ifdef CONFIG_ACPI_CUSTOM_DSDT
814 static void *amlcode __attribute__ ((weakref("AmlCode")));
815 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
816 #endif
817 
818 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
819 		       struct acpi_table_header **new_table)
820 {
821 	if (!existing_table || !new_table)
822 		return AE_BAD_PARAMETER;
823 
824 	*new_table = NULL;
825 
826 #ifdef CONFIG_ACPI_CUSTOM_DSDT
827 	if (!strncmp(existing_table->signature, "DSDT", 4)) {
828 		*new_table = (struct acpi_table_header *)&amlcode;
829 		if (!(*new_table))
830 			*new_table = (struct acpi_table_header *)&dsdt_amlcode;
831 	}
832 #endif
833 	if (*new_table != NULL)
834 		acpi_table_taint(existing_table);
835 	return AE_OK;
836 }
837 
838 /*
839  * acpi_locate_initial_tables()
840  *
841  * find RSDP, find and checksum SDT/XSDT.
842  * checksum all tables, print SDT/XSDT
843  *
844  * result: sdt_entry[] is initialized
845  */
846 
847 int __init acpi_locate_initial_tables(void)
848 {
849 	acpi_status status;
850 
851 	if (acpi_verify_table_checksum) {
852 		pr_info("Early table checksum verification enabled\n");
853 		acpi_gbl_enable_table_validation = TRUE;
854 	} else {
855 		pr_info("Early table checksum verification disabled\n");
856 		acpi_gbl_enable_table_validation = FALSE;
857 	}
858 
859 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
860 	if (ACPI_FAILURE(status))
861 		return -EINVAL;
862 
863 	return 0;
864 }
865 
866 void __init acpi_reserve_initial_tables(void)
867 {
868 	int i;
869 
870 	for (i = 0; i < ACPI_MAX_TABLES; i++) {
871 		struct acpi_table_desc *table_desc = &initial_tables[i];
872 		u64 start = table_desc->address;
873 		u64 size = table_desc->length;
874 
875 		if (!start || !size)
876 			break;
877 
878 		pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
879 			table_desc->signature.ascii, start, start + size - 1);
880 
881 		memblock_reserve(start, size);
882 	}
883 }
884 
885 void __init acpi_table_init_complete(void)
886 {
887 	acpi_table_initrd_scan();
888 	check_multiple_madt();
889 }
890 
891 int __init acpi_table_init(void)
892 {
893 	int ret;
894 
895 	ret = acpi_locate_initial_tables();
896 	if (ret)
897 		return ret;
898 
899 	acpi_table_init_complete();
900 
901 	return 0;
902 }
903 
904 static int __init acpi_parse_apic_instance(char *str)
905 {
906 	if (!str)
907 		return -EINVAL;
908 
909 	if (kstrtoint(str, 0, &acpi_apic_instance))
910 		return -EINVAL;
911 
912 	pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
913 
914 	return 0;
915 }
916 early_param("acpi_apic_instance", acpi_parse_apic_instance);
917 
918 static int __init acpi_force_table_verification_setup(char *s)
919 {
920 	acpi_verify_table_checksum = true;
921 
922 	return 0;
923 }
924 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
925 
926 static int __init acpi_force_32bit_fadt_addr(char *s)
927 {
928 	pr_info("Forcing 32 Bit FADT addresses\n");
929 	acpi_gbl_use32_bit_fadt_addresses = TRUE;
930 
931 	return 0;
932 }
933 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
934