xref: /linux/drivers/acpi/tables.c (revision eed4edda910fe34dfae8c6bfbcf57f4593a54295)
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 /*
41  * Disable table checksum verification for the early stage due to the size
42  * limitation of the current x86 early mapping implementation.
43  */
44 static bool acpi_verify_table_checksum __initdata_or_acpilib = false;
45 
46 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
47 {
48 	if (!header)
49 		return;
50 
51 	switch (header->type) {
52 
53 	case ACPI_MADT_TYPE_LOCAL_APIC:
54 		{
55 			struct acpi_madt_local_apic *p =
56 			    (struct acpi_madt_local_apic *)header;
57 			pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
58 				 p->processor_id, p->id,
59 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
60 		}
61 		break;
62 
63 	case ACPI_MADT_TYPE_LOCAL_X2APIC:
64 		{
65 			struct acpi_madt_local_x2apic *p =
66 			    (struct acpi_madt_local_x2apic *)header;
67 			pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
68 				 p->local_apic_id, p->uid,
69 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
70 		}
71 		break;
72 
73 	case ACPI_MADT_TYPE_IO_APIC:
74 		{
75 			struct acpi_madt_io_apic *p =
76 			    (struct acpi_madt_io_apic *)header;
77 			pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
78 				 p->id, p->address, p->global_irq_base);
79 		}
80 		break;
81 
82 	case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
83 		{
84 			struct acpi_madt_interrupt_override *p =
85 			    (struct acpi_madt_interrupt_override *)header;
86 			pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
87 				p->bus, p->source_irq, p->global_irq,
88 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
89 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
90 			if (p->inti_flags  &
91 			    ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
92 				pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
93 					p->inti_flags  &
94 					~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
95 		}
96 		break;
97 
98 	case ACPI_MADT_TYPE_NMI_SOURCE:
99 		{
100 			struct acpi_madt_nmi_source *p =
101 			    (struct acpi_madt_nmi_source *)header;
102 			pr_info("NMI_SRC (%s %s global_irq %d)\n",
103 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
104 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
105 				p->global_irq);
106 		}
107 		break;
108 
109 	case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
110 		{
111 			struct acpi_madt_local_apic_nmi *p =
112 			    (struct acpi_madt_local_apic_nmi *)header;
113 			pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
114 				p->processor_id,
115 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK	],
116 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
117 				p->lint);
118 		}
119 		break;
120 
121 	case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
122 		{
123 			u16 polarity, trigger;
124 			struct acpi_madt_local_x2apic_nmi *p =
125 			    (struct acpi_madt_local_x2apic_nmi *)header;
126 
127 			polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
128 			trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
129 
130 			pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
131 				p->uid,
132 				mps_inti_flags_polarity[polarity],
133 				mps_inti_flags_trigger[trigger],
134 				p->lint);
135 		}
136 		break;
137 
138 	case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
139 		{
140 			struct acpi_madt_local_apic_override *p =
141 			    (struct acpi_madt_local_apic_override *)header;
142 			pr_info("LAPIC_ADDR_OVR (address[0x%llx])\n",
143 				p->address);
144 		}
145 		break;
146 
147 	case ACPI_MADT_TYPE_IO_SAPIC:
148 		{
149 			struct acpi_madt_io_sapic *p =
150 			    (struct acpi_madt_io_sapic *)header;
151 			pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
152 				 p->id, (void *)(unsigned long)p->address,
153 				 p->global_irq_base);
154 		}
155 		break;
156 
157 	case ACPI_MADT_TYPE_LOCAL_SAPIC:
158 		{
159 			struct acpi_madt_local_sapic *p =
160 			    (struct acpi_madt_local_sapic *)header;
161 			pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
162 				 p->processor_id, p->id, p->eid,
163 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
164 		}
165 		break;
166 
167 	case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
168 		{
169 			struct acpi_madt_interrupt_source *p =
170 			    (struct acpi_madt_interrupt_source *)header;
171 			pr_info("PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
172 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
173 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
174 				p->type, p->id, p->eid, p->io_sapic_vector,
175 				p->global_irq);
176 		}
177 		break;
178 
179 	case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
180 		{
181 			struct acpi_madt_generic_interrupt *p =
182 				(struct acpi_madt_generic_interrupt *)header;
183 			pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
184 				 p->uid, p->base_address,
185 				 p->arm_mpidr,
186 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
187 
188 		}
189 		break;
190 
191 	case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
192 		{
193 			struct acpi_madt_generic_distributor *p =
194 				(struct acpi_madt_generic_distributor *)header;
195 			pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
196 				 p->gic_id, p->base_address,
197 				 p->global_irq_base);
198 		}
199 		break;
200 
201 	case ACPI_MADT_TYPE_CORE_PIC:
202 		{
203 			struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
204 
205 			pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
206 				 p->processor_id, p->core_id,
207 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
208 		}
209 		break;
210 
211 	case ACPI_MADT_TYPE_RINTC:
212 		{
213 			struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
214 
215 			pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
216 				 p->uid, p->hart_id,
217 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
218 		}
219 		break;
220 
221 	default:
222 		pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
223 			header->type);
224 		break;
225 	}
226 }
227 
228 int __init_or_acpilib acpi_table_parse_entries_array(
229 	char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
230 	int proc_num, unsigned int max_entries)
231 {
232 	struct acpi_table_header *table_header = NULL;
233 	int count;
234 	u32 instance = 0;
235 
236 	if (acpi_disabled)
237 		return -ENODEV;
238 
239 	if (!id)
240 		return -EINVAL;
241 
242 	if (!table_size)
243 		return -EINVAL;
244 
245 	if (!strncmp(id, ACPI_SIG_MADT, 4))
246 		instance = acpi_apic_instance;
247 
248 	acpi_get_table(id, instance, &table_header);
249 	if (!table_header) {
250 		pr_debug("%4.4s not present\n", id);
251 		return -ENODEV;
252 	}
253 
254 	count = acpi_parse_entries_array(id, table_size,
255 					 (union fw_table_header *)table_header,
256 					 proc, proc_num, max_entries);
257 
258 	acpi_put_table(table_header);
259 	return count;
260 }
261 
262 static int __init_or_acpilib __acpi_table_parse_entries(
263 	char *id, unsigned long table_size, int entry_id,
264 	acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
265 	void *arg, unsigned int max_entries)
266 {
267 	struct acpi_subtable_proc proc = {
268 		.id		= entry_id,
269 		.handler	= handler,
270 		.handler_arg	= handler_arg,
271 		.arg		= arg,
272 	};
273 
274 	return acpi_table_parse_entries_array(id, table_size, &proc, 1,
275 						max_entries);
276 }
277 
278 int __init_or_acpilib
279 acpi_table_parse_cedt(enum acpi_cedt_type id,
280 		      acpi_tbl_entry_handler_arg handler_arg, void *arg)
281 {
282 	return __acpi_table_parse_entries(ACPI_SIG_CEDT,
283 					  sizeof(struct acpi_table_cedt), id,
284 					  NULL, handler_arg, arg, 0);
285 }
286 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
287 
288 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
289 				    int entry_id,
290 				    acpi_tbl_entry_handler handler,
291 				    unsigned int max_entries)
292 {
293 	return __acpi_table_parse_entries(id, table_size, entry_id, handler,
294 					  NULL, NULL, max_entries);
295 }
296 
297 int __init acpi_table_parse_madt(enum acpi_madt_type id,
298 		      acpi_tbl_entry_handler handler, unsigned int max_entries)
299 {
300 	return acpi_table_parse_entries(ACPI_SIG_MADT,
301 					    sizeof(struct acpi_table_madt), id,
302 					    handler, max_entries);
303 }
304 
305 /**
306  * acpi_table_parse - find table with @id, run @handler on it
307  * @id: table id to find
308  * @handler: handler to run
309  *
310  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
311  * run @handler on it.
312  *
313  * Return 0 if table found, -errno if not.
314  */
315 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
316 {
317 	struct acpi_table_header *table = NULL;
318 
319 	if (acpi_disabled)
320 		return -ENODEV;
321 
322 	if (!id || !handler)
323 		return -EINVAL;
324 
325 	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
326 		acpi_get_table(id, acpi_apic_instance, &table);
327 	else
328 		acpi_get_table(id, 0, &table);
329 
330 	if (table) {
331 		handler(table);
332 		acpi_put_table(table);
333 		return 0;
334 	} else
335 		return -ENODEV;
336 }
337 
338 /*
339  * The BIOS is supposed to supply a single APIC/MADT,
340  * but some report two.  Provide a knob to use either.
341  * (don't you wish instance 0 and 1 were not the same?)
342  */
343 static void __init check_multiple_madt(void)
344 {
345 	struct acpi_table_header *table = NULL;
346 
347 	acpi_get_table(ACPI_SIG_MADT, 2, &table);
348 	if (table) {
349 		pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
350 			acpi_apic_instance);
351 		pr_warn("If \"acpi_apic_instance=%d\" works better, "
352 			"notify linux-acpi@vger.kernel.org\n",
353 			acpi_apic_instance ? 0 : 2);
354 		acpi_put_table(table);
355 
356 	} else
357 		acpi_apic_instance = 0;
358 
359 	return;
360 }
361 
362 static void acpi_table_taint(struct acpi_table_header *table)
363 {
364 	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
365 		table->signature, table->oem_table_id);
366 	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
367 }
368 
369 #ifdef CONFIG_ACPI_TABLE_UPGRADE
370 static u64 acpi_tables_addr;
371 static int all_tables_size;
372 
373 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
374 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
375 {
376 	u8 sum = 0;
377 	u8 *end = buffer + length;
378 
379 	while (buffer < end)
380 		sum = (u8) (sum + *(buffer++));
381 	return sum;
382 }
383 
384 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
385 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
386 	ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
387 	ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
388 	ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
389 	ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
390 	ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
391 	ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
392 	ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
393 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
394 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
395 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
396 	ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
397 	ACPI_SIG_NBFT };
398 
399 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
400 
401 #define NR_ACPI_INITRD_TABLES 64
402 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
403 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
404 
405 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
406 
407 void __init acpi_table_upgrade(void)
408 {
409 	void *data;
410 	size_t size;
411 	int sig, no, table_nr = 0, total_offset = 0;
412 	long offset = 0;
413 	struct acpi_table_header *table;
414 	char cpio_path[32] = "kernel/firmware/acpi/";
415 	struct cpio_data file;
416 
417 	if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
418 		data = __initramfs_start;
419 		size = __initramfs_size;
420 	} else {
421 		data = (void *)initrd_start;
422 		size = initrd_end - initrd_start;
423 	}
424 
425 	if (data == NULL || size == 0)
426 		return;
427 
428 	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
429 		file = find_cpio_data(cpio_path, data, size, &offset);
430 		if (!file.data)
431 			break;
432 
433 		data += offset;
434 		size -= offset;
435 
436 		if (file.size < sizeof(struct acpi_table_header)) {
437 			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
438 				cpio_path, file.name);
439 			continue;
440 		}
441 
442 		table = file.data;
443 
444 		for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
445 			if (!memcmp(table->signature, table_sigs[sig], 4))
446 				break;
447 
448 		if (sig >= ARRAY_SIZE(table_sigs)) {
449 			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
450 				cpio_path, file.name);
451 			continue;
452 		}
453 		if (file.size != table->length) {
454 			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
455 				cpio_path, file.name);
456 			continue;
457 		}
458 		if (acpi_table_checksum(file.data, table->length)) {
459 			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
460 				cpio_path, file.name);
461 			continue;
462 		}
463 
464 		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
465 			table->signature, cpio_path, file.name, table->length);
466 
467 		all_tables_size += table->length;
468 		acpi_initrd_files[table_nr].data = file.data;
469 		acpi_initrd_files[table_nr].size = file.size;
470 		table_nr++;
471 	}
472 	if (table_nr == 0)
473 		return;
474 
475 	if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
476 		pr_notice("kernel is locked down, ignoring table override\n");
477 		return;
478 	}
479 
480 	acpi_tables_addr =
481 		memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
482 					  0, ACPI_TABLE_UPGRADE_MAX_PHYS);
483 	if (!acpi_tables_addr) {
484 		WARN_ON(1);
485 		return;
486 	}
487 	/*
488 	 * Only calling e820_add_reserve does not work and the
489 	 * tables are invalid (memory got used) later.
490 	 * memblock_reserve works as expected and the tables won't get modified.
491 	 * But it's not enough on X86 because ioremap will
492 	 * complain later (used by acpi_os_map_memory) that the pages
493 	 * that should get mapped are not marked "reserved".
494 	 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
495 	 * works fine.
496 	 */
497 	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
498 
499 	kmemleak_ignore_phys(acpi_tables_addr);
500 
501 	/*
502 	 * early_ioremap only can remap 256k one time. If we map all
503 	 * tables one time, we will hit the limit. Need to map chunks
504 	 * one by one during copying the same as that in relocate_initrd().
505 	 */
506 	for (no = 0; no < table_nr; no++) {
507 		unsigned char *src_p = acpi_initrd_files[no].data;
508 		phys_addr_t size = acpi_initrd_files[no].size;
509 		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
510 		phys_addr_t slop, clen;
511 		char *dest_p;
512 
513 		total_offset += size;
514 
515 		while (size) {
516 			slop = dest_addr & ~PAGE_MASK;
517 			clen = size;
518 			if (clen > MAP_CHUNK_SIZE - slop)
519 				clen = MAP_CHUNK_SIZE - slop;
520 			dest_p = early_memremap(dest_addr & PAGE_MASK,
521 						clen + slop);
522 			memcpy(dest_p + slop, src_p, clen);
523 			early_memunmap(dest_p, clen + slop);
524 			src_p += clen;
525 			dest_addr += clen;
526 			size -= clen;
527 		}
528 	}
529 }
530 
531 static acpi_status
532 acpi_table_initrd_override(struct acpi_table_header *existing_table,
533 			   acpi_physical_address *address, u32 *length)
534 {
535 	int table_offset = 0;
536 	int table_index = 0;
537 	struct acpi_table_header *table;
538 	u32 table_length;
539 
540 	*length = 0;
541 	*address = 0;
542 	if (!acpi_tables_addr)
543 		return AE_OK;
544 
545 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
546 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
547 					   ACPI_HEADER_SIZE);
548 		if (table_offset + table->length > all_tables_size) {
549 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
550 			WARN_ON(1);
551 			return AE_OK;
552 		}
553 
554 		table_length = table->length;
555 
556 		/* Only override tables matched */
557 		if (memcmp(existing_table->signature, table->signature, 4) ||
558 		    memcmp(table->oem_id, existing_table->oem_id,
559 			   ACPI_OEM_ID_SIZE) ||
560 		    memcmp(table->oem_table_id, existing_table->oem_table_id,
561 			   ACPI_OEM_TABLE_ID_SIZE)) {
562 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
563 			goto next_table;
564 		}
565 		/*
566 		 * Mark the table to avoid being used in
567 		 * acpi_table_initrd_scan() and check the revision.
568 		 */
569 		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
570 		    existing_table->oem_revision >= table->oem_revision) {
571 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
572 			goto next_table;
573 		}
574 
575 		*length = table_length;
576 		*address = acpi_tables_addr + table_offset;
577 		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
578 			table->signature, table->oem_id,
579 			table->oem_table_id);
580 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
581 		break;
582 
583 next_table:
584 		table_offset += table_length;
585 		table_index++;
586 	}
587 	return AE_OK;
588 }
589 
590 static void __init acpi_table_initrd_scan(void)
591 {
592 	int table_offset = 0;
593 	int table_index = 0;
594 	u32 table_length;
595 	struct acpi_table_header *table;
596 
597 	if (!acpi_tables_addr)
598 		return;
599 
600 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
601 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
602 					   ACPI_HEADER_SIZE);
603 		if (table_offset + table->length > all_tables_size) {
604 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
605 			WARN_ON(1);
606 			return;
607 		}
608 
609 		table_length = table->length;
610 
611 		/* Skip RSDT/XSDT which should only be used for override */
612 		if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
613 		    ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
614 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
615 			goto next_table;
616 		}
617 		/*
618 		 * Mark the table to avoid being used in
619 		 * acpi_table_initrd_override(). Though this is not possible
620 		 * because override is disabled in acpi_install_physical_table().
621 		 */
622 		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
623 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
624 			goto next_table;
625 		}
626 
627 		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
628 			table->signature, table->oem_id,
629 			table->oem_table_id);
630 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
631 		acpi_install_physical_table(acpi_tables_addr + table_offset);
632 next_table:
633 		table_offset += table_length;
634 		table_index++;
635 	}
636 }
637 #else
638 static acpi_status
639 acpi_table_initrd_override(struct acpi_table_header *existing_table,
640 			   acpi_physical_address *address,
641 			   u32 *table_length)
642 {
643 	*table_length = 0;
644 	*address = 0;
645 	return AE_OK;
646 }
647 
648 static void __init acpi_table_initrd_scan(void)
649 {
650 }
651 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
652 
653 acpi_status
654 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
655 				acpi_physical_address *address,
656 				u32 *table_length)
657 {
658 	return acpi_table_initrd_override(existing_table, address,
659 					  table_length);
660 }
661 
662 #ifdef CONFIG_ACPI_CUSTOM_DSDT
663 static void *amlcode __attribute__ ((weakref("AmlCode")));
664 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
665 #endif
666 
667 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
668 		       struct acpi_table_header **new_table)
669 {
670 	if (!existing_table || !new_table)
671 		return AE_BAD_PARAMETER;
672 
673 	*new_table = NULL;
674 
675 #ifdef CONFIG_ACPI_CUSTOM_DSDT
676 	if (!strncmp(existing_table->signature, "DSDT", 4)) {
677 		*new_table = (struct acpi_table_header *)&amlcode;
678 		if (!(*new_table))
679 			*new_table = (struct acpi_table_header *)&dsdt_amlcode;
680 	}
681 #endif
682 	if (*new_table != NULL)
683 		acpi_table_taint(existing_table);
684 	return AE_OK;
685 }
686 
687 /*
688  * acpi_locate_initial_tables()
689  *
690  * Get the RSDP, then find and checksum all the ACPI tables.
691  *
692  * result: initial_tables[] is initialized, and points to
693  * a list of ACPI tables.
694  */
695 int __init acpi_locate_initial_tables(void)
696 {
697 	acpi_status status;
698 
699 	if (acpi_verify_table_checksum) {
700 		pr_info("Early table checksum verification enabled\n");
701 		acpi_gbl_enable_table_validation = TRUE;
702 	} else {
703 		pr_info("Early table checksum verification disabled\n");
704 		acpi_gbl_enable_table_validation = FALSE;
705 	}
706 
707 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
708 	if (ACPI_FAILURE(status))
709 		return -EINVAL;
710 
711 	return 0;
712 }
713 
714 void __init acpi_reserve_initial_tables(void)
715 {
716 	int i;
717 
718 	for (i = 0; i < ACPI_MAX_TABLES; i++) {
719 		struct acpi_table_desc *table_desc = &initial_tables[i];
720 		u64 start = table_desc->address;
721 		u64 size = table_desc->length;
722 
723 		if (!start || !size)
724 			break;
725 
726 		pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
727 			table_desc->signature.ascii, start, start + size - 1);
728 
729 		memblock_reserve(start, size);
730 	}
731 }
732 
733 void __init acpi_table_init_complete(void)
734 {
735 	acpi_table_initrd_scan();
736 	check_multiple_madt();
737 }
738 
739 int __init acpi_table_init(void)
740 {
741 	int ret;
742 
743 	ret = acpi_locate_initial_tables();
744 	if (ret)
745 		return ret;
746 
747 	acpi_table_init_complete();
748 
749 	return 0;
750 }
751 
752 static int __init acpi_parse_apic_instance(char *str)
753 {
754 	if (!str)
755 		return -EINVAL;
756 
757 	if (kstrtoint(str, 0, &acpi_apic_instance))
758 		return -EINVAL;
759 
760 	pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
761 
762 	return 0;
763 }
764 early_param("acpi_apic_instance", acpi_parse_apic_instance);
765 
766 static int __init acpi_force_table_verification_setup(char *s)
767 {
768 	acpi_verify_table_checksum = true;
769 
770 	return 0;
771 }
772 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
773 
774 static int __init acpi_force_32bit_fadt_addr(char *s)
775 {
776 	pr_info("Forcing 32 Bit FADT addresses\n");
777 	acpi_gbl_use32_bit_fadt_addresses = TRUE;
778 
779 	return 0;
780 }
781 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
782