xref: /linux/drivers/acpi/tables.c (revision d53b8e36925256097a08d7cb749198d85cbf9b2b)
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_MULTIPROC_WAKEUP:
202 		{
203 			struct acpi_madt_multiproc_wakeup *p =
204 				(struct acpi_madt_multiproc_wakeup *)header;
205 			u64 reset_vector = 0;
206 
207 			if (p->version >= ACPI_MADT_MP_WAKEUP_VERSION_V1)
208 				reset_vector = p->reset_vector;
209 
210 			pr_debug("MP Wakeup (version[%d], mailbox[%#llx], reset[%#llx])\n",
211 				 p->version, p->mailbox_address, reset_vector);
212 		}
213 		break;
214 
215 	case ACPI_MADT_TYPE_CORE_PIC:
216 		{
217 			struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
218 
219 			pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
220 				 p->processor_id, p->core_id,
221 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
222 		}
223 		break;
224 
225 	case ACPI_MADT_TYPE_RINTC:
226 		{
227 			struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
228 
229 			pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
230 				 p->uid, p->hart_id,
231 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
232 		}
233 		break;
234 
235 	default:
236 		pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
237 			header->type);
238 		break;
239 	}
240 }
241 
242 int __init_or_acpilib acpi_table_parse_entries_array(
243 	char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
244 	int proc_num, unsigned int max_entries)
245 {
246 	struct acpi_table_header *table_header = NULL;
247 	int count;
248 	u32 instance = 0;
249 
250 	if (acpi_disabled)
251 		return -ENODEV;
252 
253 	if (!id)
254 		return -EINVAL;
255 
256 	if (!table_size)
257 		return -EINVAL;
258 
259 	if (!strncmp(id, ACPI_SIG_MADT, 4))
260 		instance = acpi_apic_instance;
261 
262 	acpi_get_table(id, instance, &table_header);
263 	if (!table_header) {
264 		pr_debug("%4.4s not present\n", id);
265 		return -ENODEV;
266 	}
267 
268 	count = acpi_parse_entries_array(id, table_size,
269 					 (union fw_table_header *)table_header,
270 					 0, proc, proc_num, max_entries);
271 
272 	acpi_put_table(table_header);
273 	return count;
274 }
275 
276 static int __init_or_acpilib __acpi_table_parse_entries(
277 	char *id, unsigned long table_size, int entry_id,
278 	acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
279 	void *arg, unsigned int max_entries)
280 {
281 	struct acpi_subtable_proc proc = {
282 		.id		= entry_id,
283 		.handler	= handler,
284 		.handler_arg	= handler_arg,
285 		.arg		= arg,
286 	};
287 
288 	return acpi_table_parse_entries_array(id, table_size, &proc, 1,
289 						max_entries);
290 }
291 
292 int __init_or_acpilib
293 acpi_table_parse_cedt(enum acpi_cedt_type id,
294 		      acpi_tbl_entry_handler_arg handler_arg, void *arg)
295 {
296 	return __acpi_table_parse_entries(ACPI_SIG_CEDT,
297 					  sizeof(struct acpi_table_cedt), id,
298 					  NULL, handler_arg, arg, 0);
299 }
300 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
301 
302 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
303 				    int entry_id,
304 				    acpi_tbl_entry_handler handler,
305 				    unsigned int max_entries)
306 {
307 	return __acpi_table_parse_entries(id, table_size, entry_id, handler,
308 					  NULL, NULL, max_entries);
309 }
310 
311 int __init acpi_table_parse_madt(enum acpi_madt_type id,
312 		      acpi_tbl_entry_handler handler, unsigned int max_entries)
313 {
314 	return acpi_table_parse_entries(ACPI_SIG_MADT,
315 					    sizeof(struct acpi_table_madt), id,
316 					    handler, max_entries);
317 }
318 
319 /**
320  * acpi_table_parse - find table with @id, run @handler on it
321  * @id: table id to find
322  * @handler: handler to run
323  *
324  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
325  * run @handler on it.
326  *
327  * Return 0 if table found, -errno if not.
328  */
329 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
330 {
331 	struct acpi_table_header *table = NULL;
332 
333 	if (acpi_disabled)
334 		return -ENODEV;
335 
336 	if (!id || !handler)
337 		return -EINVAL;
338 
339 	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
340 		acpi_get_table(id, acpi_apic_instance, &table);
341 	else
342 		acpi_get_table(id, 0, &table);
343 
344 	if (table) {
345 		handler(table);
346 		acpi_put_table(table);
347 		return 0;
348 	} else
349 		return -ENODEV;
350 }
351 
352 /*
353  * The BIOS is supposed to supply a single APIC/MADT,
354  * but some report two.  Provide a knob to use either.
355  * (don't you wish instance 0 and 1 were not the same?)
356  */
357 static void __init check_multiple_madt(void)
358 {
359 	struct acpi_table_header *table = NULL;
360 
361 	acpi_get_table(ACPI_SIG_MADT, 2, &table);
362 	if (table) {
363 		pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
364 			acpi_apic_instance);
365 		pr_warn("If \"acpi_apic_instance=%d\" works better, "
366 			"notify linux-acpi@vger.kernel.org\n",
367 			acpi_apic_instance ? 0 : 2);
368 		acpi_put_table(table);
369 
370 	} else
371 		acpi_apic_instance = 0;
372 
373 	return;
374 }
375 
376 static void acpi_table_taint(struct acpi_table_header *table)
377 {
378 	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
379 		table->signature, table->oem_table_id);
380 	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
381 }
382 
383 #ifdef CONFIG_ACPI_TABLE_UPGRADE
384 static u64 acpi_tables_addr;
385 static int all_tables_size;
386 
387 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
388 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
389 {
390 	u8 sum = 0;
391 	u8 *end = buffer + length;
392 
393 	while (buffer < end)
394 		sum = (u8) (sum + *(buffer++));
395 	return sum;
396 }
397 
398 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
399 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
400 	ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
401 	ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
402 	ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
403 	ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
404 	ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
405 	ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
406 	ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
407 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
408 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
409 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
410 	ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
411 	ACPI_SIG_NBFT };
412 
413 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
414 
415 #define NR_ACPI_INITRD_TABLES 64
416 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
417 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
418 
419 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
420 
421 void __init acpi_table_upgrade(void)
422 {
423 	void *data;
424 	size_t size;
425 	int sig, no, table_nr = 0, total_offset = 0;
426 	long offset = 0;
427 	struct acpi_table_header *table;
428 	char cpio_path[32] = "kernel/firmware/acpi/";
429 	struct cpio_data file;
430 
431 	if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
432 		data = __initramfs_start;
433 		size = __initramfs_size;
434 	} else {
435 		data = (void *)initrd_start;
436 		size = initrd_end - initrd_start;
437 	}
438 
439 	if (data == NULL || size == 0)
440 		return;
441 
442 	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
443 		file = find_cpio_data(cpio_path, data, size, &offset);
444 		if (!file.data)
445 			break;
446 
447 		data += offset;
448 		size -= offset;
449 
450 		if (file.size < sizeof(struct acpi_table_header)) {
451 			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
452 				cpio_path, file.name);
453 			continue;
454 		}
455 
456 		table = file.data;
457 
458 		for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
459 			if (!memcmp(table->signature, table_sigs[sig], 4))
460 				break;
461 
462 		if (sig >= ARRAY_SIZE(table_sigs)) {
463 			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
464 				cpio_path, file.name);
465 			continue;
466 		}
467 		if (file.size != table->length) {
468 			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
469 				cpio_path, file.name);
470 			continue;
471 		}
472 		if (acpi_table_checksum(file.data, table->length)) {
473 			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
474 				cpio_path, file.name);
475 			continue;
476 		}
477 
478 		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
479 			table->signature, cpio_path, file.name, table->length);
480 
481 		all_tables_size += table->length;
482 		acpi_initrd_files[table_nr].data = file.data;
483 		acpi_initrd_files[table_nr].size = file.size;
484 		table_nr++;
485 	}
486 	if (table_nr == 0)
487 		return;
488 
489 	if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
490 		pr_notice("kernel is locked down, ignoring table override\n");
491 		return;
492 	}
493 
494 	acpi_tables_addr =
495 		memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
496 					  0, ACPI_TABLE_UPGRADE_MAX_PHYS);
497 	if (!acpi_tables_addr) {
498 		WARN_ON(1);
499 		return;
500 	}
501 	/*
502 	 * Only calling e820_add_reserve does not work and the
503 	 * tables are invalid (memory got used) later.
504 	 * memblock_reserve works as expected and the tables won't get modified.
505 	 * But it's not enough on X86 because ioremap will
506 	 * complain later (used by acpi_os_map_memory) that the pages
507 	 * that should get mapped are not marked "reserved".
508 	 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
509 	 * works fine.
510 	 */
511 	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
512 
513 	kmemleak_ignore_phys(acpi_tables_addr);
514 
515 	/*
516 	 * early_ioremap only can remap 256k one time. If we map all
517 	 * tables one time, we will hit the limit. Need to map chunks
518 	 * one by one during copying the same as that in relocate_initrd().
519 	 */
520 	for (no = 0; no < table_nr; no++) {
521 		unsigned char *src_p = acpi_initrd_files[no].data;
522 		phys_addr_t size = acpi_initrd_files[no].size;
523 		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
524 		phys_addr_t slop, clen;
525 		char *dest_p;
526 
527 		total_offset += size;
528 
529 		while (size) {
530 			slop = dest_addr & ~PAGE_MASK;
531 			clen = size;
532 			if (clen > MAP_CHUNK_SIZE - slop)
533 				clen = MAP_CHUNK_SIZE - slop;
534 			dest_p = early_memremap(dest_addr & PAGE_MASK,
535 						clen + slop);
536 			memcpy(dest_p + slop, src_p, clen);
537 			early_memunmap(dest_p, clen + slop);
538 			src_p += clen;
539 			dest_addr += clen;
540 			size -= clen;
541 		}
542 	}
543 }
544 
545 static acpi_status
546 acpi_table_initrd_override(struct acpi_table_header *existing_table,
547 			   acpi_physical_address *address, u32 *length)
548 {
549 	int table_offset = 0;
550 	int table_index = 0;
551 	struct acpi_table_header *table;
552 	u32 table_length;
553 
554 	*length = 0;
555 	*address = 0;
556 	if (!acpi_tables_addr)
557 		return AE_OK;
558 
559 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
560 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
561 					   ACPI_HEADER_SIZE);
562 		if (table_offset + table->length > all_tables_size) {
563 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
564 			WARN_ON(1);
565 			return AE_OK;
566 		}
567 
568 		table_length = table->length;
569 
570 		/* Only override tables matched */
571 		if (memcmp(existing_table->signature, table->signature, 4) ||
572 		    memcmp(table->oem_id, existing_table->oem_id,
573 			   ACPI_OEM_ID_SIZE) ||
574 		    memcmp(table->oem_table_id, existing_table->oem_table_id,
575 			   ACPI_OEM_TABLE_ID_SIZE)) {
576 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
577 			goto next_table;
578 		}
579 		/*
580 		 * Mark the table to avoid being used in
581 		 * acpi_table_initrd_scan() and check the revision.
582 		 */
583 		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
584 		    existing_table->oem_revision >= table->oem_revision) {
585 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
586 			goto next_table;
587 		}
588 
589 		*length = table_length;
590 		*address = acpi_tables_addr + table_offset;
591 		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
592 			table->signature, table->oem_id,
593 			table->oem_table_id);
594 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
595 		break;
596 
597 next_table:
598 		table_offset += table_length;
599 		table_index++;
600 	}
601 	return AE_OK;
602 }
603 
604 static void __init acpi_table_initrd_scan(void)
605 {
606 	int table_offset = 0;
607 	int table_index = 0;
608 	u32 table_length;
609 	struct acpi_table_header *table;
610 
611 	if (!acpi_tables_addr)
612 		return;
613 
614 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
615 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
616 					   ACPI_HEADER_SIZE);
617 		if (table_offset + table->length > all_tables_size) {
618 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
619 			WARN_ON(1);
620 			return;
621 		}
622 
623 		table_length = table->length;
624 
625 		/* Skip RSDT/XSDT which should only be used for override */
626 		if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
627 		    ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
628 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
629 			goto next_table;
630 		}
631 		/*
632 		 * Mark the table to avoid being used in
633 		 * acpi_table_initrd_override(). Though this is not possible
634 		 * because override is disabled in acpi_install_physical_table().
635 		 */
636 		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
637 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
638 			goto next_table;
639 		}
640 
641 		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
642 			table->signature, table->oem_id,
643 			table->oem_table_id);
644 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
645 		acpi_install_physical_table(acpi_tables_addr + table_offset);
646 next_table:
647 		table_offset += table_length;
648 		table_index++;
649 	}
650 }
651 #else
652 static acpi_status
653 acpi_table_initrd_override(struct acpi_table_header *existing_table,
654 			   acpi_physical_address *address,
655 			   u32 *table_length)
656 {
657 	*table_length = 0;
658 	*address = 0;
659 	return AE_OK;
660 }
661 
662 static void __init acpi_table_initrd_scan(void)
663 {
664 }
665 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
666 
667 acpi_status
668 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
669 				acpi_physical_address *address,
670 				u32 *table_length)
671 {
672 	return acpi_table_initrd_override(existing_table, address,
673 					  table_length);
674 }
675 
676 #ifdef CONFIG_ACPI_CUSTOM_DSDT
677 static void *amlcode __attribute__ ((weakref("AmlCode")));
678 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
679 #endif
680 
681 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
682 		       struct acpi_table_header **new_table)
683 {
684 	if (!existing_table || !new_table)
685 		return AE_BAD_PARAMETER;
686 
687 	*new_table = NULL;
688 
689 #ifdef CONFIG_ACPI_CUSTOM_DSDT
690 	if (!strncmp(existing_table->signature, "DSDT", 4)) {
691 		*new_table = (struct acpi_table_header *)&amlcode;
692 		if (!(*new_table))
693 			*new_table = (struct acpi_table_header *)&dsdt_amlcode;
694 	}
695 #endif
696 	if (*new_table != NULL)
697 		acpi_table_taint(existing_table);
698 	return AE_OK;
699 }
700 
701 /*
702  * acpi_locate_initial_tables()
703  *
704  * Get the RSDP, then find and checksum all the ACPI tables.
705  *
706  * result: initial_tables[] is initialized, and points to
707  * a list of ACPI tables.
708  */
709 int __init acpi_locate_initial_tables(void)
710 {
711 	acpi_status status;
712 
713 	if (acpi_verify_table_checksum) {
714 		pr_info("Early table checksum verification enabled\n");
715 		acpi_gbl_enable_table_validation = TRUE;
716 	} else {
717 		pr_info("Early table checksum verification disabled\n");
718 		acpi_gbl_enable_table_validation = FALSE;
719 	}
720 
721 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
722 	if (ACPI_FAILURE(status))
723 		return -EINVAL;
724 
725 	return 0;
726 }
727 
728 void __init acpi_reserve_initial_tables(void)
729 {
730 	int i;
731 
732 	for (i = 0; i < ACPI_MAX_TABLES; i++) {
733 		struct acpi_table_desc *table_desc = &initial_tables[i];
734 		u64 start = table_desc->address;
735 		u64 size = table_desc->length;
736 
737 		if (!start || !size)
738 			break;
739 
740 		pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
741 			table_desc->signature.ascii, start, start + size - 1);
742 
743 		memblock_reserve(start, size);
744 	}
745 }
746 
747 void __init acpi_table_init_complete(void)
748 {
749 	acpi_table_initrd_scan();
750 	check_multiple_madt();
751 }
752 
753 int __init acpi_table_init(void)
754 {
755 	int ret;
756 
757 	ret = acpi_locate_initial_tables();
758 	if (ret)
759 		return ret;
760 
761 	acpi_table_init_complete();
762 
763 	return 0;
764 }
765 
766 static int __init acpi_parse_apic_instance(char *str)
767 {
768 	if (!str)
769 		return -EINVAL;
770 
771 	if (kstrtoint(str, 0, &acpi_apic_instance))
772 		return -EINVAL;
773 
774 	pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
775 
776 	return 0;
777 }
778 early_param("acpi_apic_instance", acpi_parse_apic_instance);
779 
780 static int __init acpi_force_table_verification_setup(char *s)
781 {
782 	acpi_verify_table_checksum = true;
783 
784 	return 0;
785 }
786 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
787 
788 static int __init acpi_force_32bit_fadt_addr(char *s)
789 {
790 	pr_info("Forcing 32 Bit FADT addresses\n");
791 	acpi_gbl_use32_bit_fadt_addresses = TRUE;
792 
793 	return 0;
794 }
795 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
796