xref: /openbmc/linux/drivers/acpi/tables.c (revision 7559e757)
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 	case ACPI_MADT_TYPE_CORE_PIC:
214 		{
215 			struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
216 
217 			pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
218 				 p->processor_id, p->core_id,
219 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
220 		}
221 		break;
222 
223 	case ACPI_MADT_TYPE_RINTC:
224 		{
225 			struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
226 
227 			pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
228 				 p->uid, p->hart_id,
229 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
230 		}
231 		break;
232 
233 	default:
234 		pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
235 			header->type);
236 		break;
237 	}
238 }
239 
240 static unsigned long __init_or_acpilib
241 acpi_get_entry_type(struct acpi_subtable_entry *entry)
242 {
243 	switch (entry->type) {
244 	case ACPI_SUBTABLE_COMMON:
245 		return entry->hdr->common.type;
246 	case ACPI_SUBTABLE_HMAT:
247 		return entry->hdr->hmat.type;
248 	case ACPI_SUBTABLE_PRMT:
249 		return 0;
250 	case ACPI_SUBTABLE_CEDT:
251 		return entry->hdr->cedt.type;
252 	}
253 	return 0;
254 }
255 
256 static unsigned long __init_or_acpilib
257 acpi_get_entry_length(struct acpi_subtable_entry *entry)
258 {
259 	switch (entry->type) {
260 	case ACPI_SUBTABLE_COMMON:
261 		return entry->hdr->common.length;
262 	case ACPI_SUBTABLE_HMAT:
263 		return entry->hdr->hmat.length;
264 	case ACPI_SUBTABLE_PRMT:
265 		return entry->hdr->prmt.length;
266 	case ACPI_SUBTABLE_CEDT:
267 		return entry->hdr->cedt.length;
268 	}
269 	return 0;
270 }
271 
272 static unsigned long __init_or_acpilib
273 acpi_get_subtable_header_length(struct acpi_subtable_entry *entry)
274 {
275 	switch (entry->type) {
276 	case ACPI_SUBTABLE_COMMON:
277 		return sizeof(entry->hdr->common);
278 	case ACPI_SUBTABLE_HMAT:
279 		return sizeof(entry->hdr->hmat);
280 	case ACPI_SUBTABLE_PRMT:
281 		return sizeof(entry->hdr->prmt);
282 	case ACPI_SUBTABLE_CEDT:
283 		return sizeof(entry->hdr->cedt);
284 	}
285 	return 0;
286 }
287 
288 static enum acpi_subtable_type __init_or_acpilib
289 acpi_get_subtable_type(char *id)
290 {
291 	if (strncmp(id, ACPI_SIG_HMAT, 4) == 0)
292 		return ACPI_SUBTABLE_HMAT;
293 	if (strncmp(id, ACPI_SIG_PRMT, 4) == 0)
294 		return ACPI_SUBTABLE_PRMT;
295 	if (strncmp(id, ACPI_SIG_CEDT, 4) == 0)
296 		return ACPI_SUBTABLE_CEDT;
297 	return ACPI_SUBTABLE_COMMON;
298 }
299 
300 static __init_or_acpilib bool has_handler(struct acpi_subtable_proc *proc)
301 {
302 	return proc->handler || proc->handler_arg;
303 }
304 
305 static __init_or_acpilib int call_handler(struct acpi_subtable_proc *proc,
306 					  union acpi_subtable_headers *hdr,
307 					  unsigned long end)
308 {
309 	if (proc->handler)
310 		return proc->handler(hdr, end);
311 	if (proc->handler_arg)
312 		return proc->handler_arg(hdr, proc->arg, end);
313 	return -EINVAL;
314 }
315 
316 /**
317  * acpi_parse_entries_array - for each proc_num find a suitable subtable
318  *
319  * @id: table id (for debugging purposes)
320  * @table_size: size of the root table
321  * @table_header: where does the table start?
322  * @proc: array of acpi_subtable_proc struct containing entry id
323  *        and associated handler with it
324  * @proc_num: how big proc is?
325  * @max_entries: how many entries can we process?
326  *
327  * For each proc_num find a subtable with proc->id and run proc->handler
328  * on it. Assumption is that there's only single handler for particular
329  * entry id.
330  *
331  * The table_size is not the size of the complete ACPI table (the length
332  * field in the header struct), but only the size of the root table; i.e.,
333  * the offset from the very first byte of the complete ACPI table, to the
334  * first byte of the very first subtable.
335  *
336  * On success returns sum of all matching entries for all proc handlers.
337  * Otherwise, -ENODEV or -EINVAL is returned.
338  */
339 static int __init_or_acpilib acpi_parse_entries_array(
340 	char *id, unsigned long table_size,
341 	struct acpi_table_header *table_header, struct acpi_subtable_proc *proc,
342 	int proc_num, unsigned int max_entries)
343 {
344 	struct acpi_subtable_entry entry;
345 	unsigned long table_end, subtable_len, entry_len;
346 	int count = 0;
347 	int errs = 0;
348 	int i;
349 
350 	table_end = (unsigned long)table_header + table_header->length;
351 
352 	/* Parse all entries looking for a match. */
353 
354 	entry.type = acpi_get_subtable_type(id);
355 	entry.hdr = (union acpi_subtable_headers *)
356 	    ((unsigned long)table_header + table_size);
357 	subtable_len = acpi_get_subtable_header_length(&entry);
358 
359 	while (((unsigned long)entry.hdr) + subtable_len  < table_end) {
360 		if (max_entries && count >= max_entries)
361 			break;
362 
363 		for (i = 0; i < proc_num; i++) {
364 			if (acpi_get_entry_type(&entry) != proc[i].id)
365 				continue;
366 			if (!has_handler(&proc[i]) ||
367 			    (!errs &&
368 			     call_handler(&proc[i], entry.hdr, table_end))) {
369 				errs++;
370 				continue;
371 			}
372 
373 			proc[i].count++;
374 			break;
375 		}
376 		if (i != proc_num)
377 			count++;
378 
379 		/*
380 		 * If entry->length is 0, break from this loop to avoid
381 		 * infinite loop.
382 		 */
383 		entry_len = acpi_get_entry_length(&entry);
384 		if (entry_len == 0) {
385 			pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
386 			return -EINVAL;
387 		}
388 
389 		entry.hdr = (union acpi_subtable_headers *)
390 		    ((unsigned long)entry.hdr + entry_len);
391 	}
392 
393 	if (max_entries && count > max_entries) {
394 		pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
395 			id, proc->id, count);
396 	}
397 
398 	return errs ? -EINVAL : count;
399 }
400 
401 int __init_or_acpilib acpi_table_parse_entries_array(
402 	char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
403 	int proc_num, unsigned int max_entries)
404 {
405 	struct acpi_table_header *table_header = NULL;
406 	int count;
407 	u32 instance = 0;
408 
409 	if (acpi_disabled)
410 		return -ENODEV;
411 
412 	if (!id)
413 		return -EINVAL;
414 
415 	if (!table_size)
416 		return -EINVAL;
417 
418 	if (!strncmp(id, ACPI_SIG_MADT, 4))
419 		instance = acpi_apic_instance;
420 
421 	acpi_get_table(id, instance, &table_header);
422 	if (!table_header) {
423 		pr_debug("%4.4s not present\n", id);
424 		return -ENODEV;
425 	}
426 
427 	count = acpi_parse_entries_array(id, table_size, table_header,
428 			proc, proc_num, max_entries);
429 
430 	acpi_put_table(table_header);
431 	return count;
432 }
433 
434 static int __init_or_acpilib __acpi_table_parse_entries(
435 	char *id, unsigned long table_size, int entry_id,
436 	acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
437 	void *arg, unsigned int max_entries)
438 {
439 	struct acpi_subtable_proc proc = {
440 		.id		= entry_id,
441 		.handler	= handler,
442 		.handler_arg	= handler_arg,
443 		.arg		= arg,
444 	};
445 
446 	return acpi_table_parse_entries_array(id, table_size, &proc, 1,
447 						max_entries);
448 }
449 
450 int __init_or_acpilib
451 acpi_table_parse_cedt(enum acpi_cedt_type id,
452 		      acpi_tbl_entry_handler_arg handler_arg, void *arg)
453 {
454 	return __acpi_table_parse_entries(ACPI_SIG_CEDT,
455 					  sizeof(struct acpi_table_cedt), id,
456 					  NULL, handler_arg, arg, 0);
457 }
458 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
459 
460 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
461 				    int entry_id,
462 				    acpi_tbl_entry_handler handler,
463 				    unsigned int max_entries)
464 {
465 	return __acpi_table_parse_entries(id, table_size, entry_id, handler,
466 					  NULL, NULL, max_entries);
467 }
468 
469 int __init acpi_table_parse_madt(enum acpi_madt_type id,
470 		      acpi_tbl_entry_handler handler, unsigned int max_entries)
471 {
472 	return acpi_table_parse_entries(ACPI_SIG_MADT,
473 					    sizeof(struct acpi_table_madt), id,
474 					    handler, max_entries);
475 }
476 
477 /**
478  * acpi_table_parse - find table with @id, run @handler on it
479  * @id: table id to find
480  * @handler: handler to run
481  *
482  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
483  * run @handler on it.
484  *
485  * Return 0 if table found, -errno if not.
486  */
487 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
488 {
489 	struct acpi_table_header *table = NULL;
490 
491 	if (acpi_disabled)
492 		return -ENODEV;
493 
494 	if (!id || !handler)
495 		return -EINVAL;
496 
497 	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
498 		acpi_get_table(id, acpi_apic_instance, &table);
499 	else
500 		acpi_get_table(id, 0, &table);
501 
502 	if (table) {
503 		handler(table);
504 		acpi_put_table(table);
505 		return 0;
506 	} else
507 		return -ENODEV;
508 }
509 
510 /*
511  * The BIOS is supposed to supply a single APIC/MADT,
512  * but some report two.  Provide a knob to use either.
513  * (don't you wish instance 0 and 1 were not the same?)
514  */
515 static void __init check_multiple_madt(void)
516 {
517 	struct acpi_table_header *table = NULL;
518 
519 	acpi_get_table(ACPI_SIG_MADT, 2, &table);
520 	if (table) {
521 		pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
522 			acpi_apic_instance);
523 		pr_warn("If \"acpi_apic_instance=%d\" works better, "
524 			"notify linux-acpi@vger.kernel.org\n",
525 			acpi_apic_instance ? 0 : 2);
526 		acpi_put_table(table);
527 
528 	} else
529 		acpi_apic_instance = 0;
530 
531 	return;
532 }
533 
534 static void acpi_table_taint(struct acpi_table_header *table)
535 {
536 	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
537 		table->signature, table->oem_table_id);
538 	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
539 }
540 
541 #ifdef CONFIG_ACPI_TABLE_UPGRADE
542 static u64 acpi_tables_addr;
543 static int all_tables_size;
544 
545 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
546 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
547 {
548 	u8 sum = 0;
549 	u8 *end = buffer + length;
550 
551 	while (buffer < end)
552 		sum = (u8) (sum + *(buffer++));
553 	return sum;
554 }
555 
556 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
557 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
558 	ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
559 	ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
560 	ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
561 	ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
562 	ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
563 	ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
564 	ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
565 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
566 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
567 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
568 	ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
569 	ACPI_SIG_NBFT };
570 
571 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
572 
573 #define NR_ACPI_INITRD_TABLES 64
574 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
575 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
576 
577 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
578 
579 void __init acpi_table_upgrade(void)
580 {
581 	void *data;
582 	size_t size;
583 	int sig, no, table_nr = 0, total_offset = 0;
584 	long offset = 0;
585 	struct acpi_table_header *table;
586 	char cpio_path[32] = "kernel/firmware/acpi/";
587 	struct cpio_data file;
588 
589 	if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
590 		data = __initramfs_start;
591 		size = __initramfs_size;
592 	} else {
593 		data = (void *)initrd_start;
594 		size = initrd_end - initrd_start;
595 	}
596 
597 	if (data == NULL || size == 0)
598 		return;
599 
600 	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
601 		file = find_cpio_data(cpio_path, data, size, &offset);
602 		if (!file.data)
603 			break;
604 
605 		data += offset;
606 		size -= offset;
607 
608 		if (file.size < sizeof(struct acpi_table_header)) {
609 			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
610 				cpio_path, file.name);
611 			continue;
612 		}
613 
614 		table = file.data;
615 
616 		for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
617 			if (!memcmp(table->signature, table_sigs[sig], 4))
618 				break;
619 
620 		if (sig >= ARRAY_SIZE(table_sigs)) {
621 			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
622 				cpio_path, file.name);
623 			continue;
624 		}
625 		if (file.size != table->length) {
626 			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
627 				cpio_path, file.name);
628 			continue;
629 		}
630 		if (acpi_table_checksum(file.data, table->length)) {
631 			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
632 				cpio_path, file.name);
633 			continue;
634 		}
635 
636 		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
637 			table->signature, cpio_path, file.name, table->length);
638 
639 		all_tables_size += table->length;
640 		acpi_initrd_files[table_nr].data = file.data;
641 		acpi_initrd_files[table_nr].size = file.size;
642 		table_nr++;
643 	}
644 	if (table_nr == 0)
645 		return;
646 
647 	if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
648 		pr_notice("kernel is locked down, ignoring table override\n");
649 		return;
650 	}
651 
652 	acpi_tables_addr =
653 		memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
654 					  0, ACPI_TABLE_UPGRADE_MAX_PHYS);
655 	if (!acpi_tables_addr) {
656 		WARN_ON(1);
657 		return;
658 	}
659 	/*
660 	 * Only calling e820_add_reserve does not work and the
661 	 * tables are invalid (memory got used) later.
662 	 * memblock_reserve works as expected and the tables won't get modified.
663 	 * But it's not enough on X86 because ioremap will
664 	 * complain later (used by acpi_os_map_memory) that the pages
665 	 * that should get mapped are not marked "reserved".
666 	 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
667 	 * works fine.
668 	 */
669 	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
670 
671 	kmemleak_ignore_phys(acpi_tables_addr);
672 
673 	/*
674 	 * early_ioremap only can remap 256k one time. If we map all
675 	 * tables one time, we will hit the limit. Need to map chunks
676 	 * one by one during copying the same as that in relocate_initrd().
677 	 */
678 	for (no = 0; no < table_nr; no++) {
679 		unsigned char *src_p = acpi_initrd_files[no].data;
680 		phys_addr_t size = acpi_initrd_files[no].size;
681 		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
682 		phys_addr_t slop, clen;
683 		char *dest_p;
684 
685 		total_offset += size;
686 
687 		while (size) {
688 			slop = dest_addr & ~PAGE_MASK;
689 			clen = size;
690 			if (clen > MAP_CHUNK_SIZE - slop)
691 				clen = MAP_CHUNK_SIZE - slop;
692 			dest_p = early_memremap(dest_addr & PAGE_MASK,
693 						clen + slop);
694 			memcpy(dest_p + slop, src_p, clen);
695 			early_memunmap(dest_p, clen + slop);
696 			src_p += clen;
697 			dest_addr += clen;
698 			size -= clen;
699 		}
700 	}
701 }
702 
703 static acpi_status
704 acpi_table_initrd_override(struct acpi_table_header *existing_table,
705 			   acpi_physical_address *address, u32 *length)
706 {
707 	int table_offset = 0;
708 	int table_index = 0;
709 	struct acpi_table_header *table;
710 	u32 table_length;
711 
712 	*length = 0;
713 	*address = 0;
714 	if (!acpi_tables_addr)
715 		return AE_OK;
716 
717 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
718 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
719 					   ACPI_HEADER_SIZE);
720 		if (table_offset + table->length > all_tables_size) {
721 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
722 			WARN_ON(1);
723 			return AE_OK;
724 		}
725 
726 		table_length = table->length;
727 
728 		/* Only override tables matched */
729 		if (memcmp(existing_table->signature, table->signature, 4) ||
730 		    memcmp(table->oem_id, existing_table->oem_id,
731 			   ACPI_OEM_ID_SIZE) ||
732 		    memcmp(table->oem_table_id, existing_table->oem_table_id,
733 			   ACPI_OEM_TABLE_ID_SIZE)) {
734 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
735 			goto next_table;
736 		}
737 		/*
738 		 * Mark the table to avoid being used in
739 		 * acpi_table_initrd_scan() and check the revision.
740 		 */
741 		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
742 		    existing_table->oem_revision >= table->oem_revision) {
743 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
744 			goto next_table;
745 		}
746 
747 		*length = table_length;
748 		*address = acpi_tables_addr + table_offset;
749 		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
750 			table->signature, table->oem_id,
751 			table->oem_table_id);
752 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
753 		break;
754 
755 next_table:
756 		table_offset += table_length;
757 		table_index++;
758 	}
759 	return AE_OK;
760 }
761 
762 static void __init acpi_table_initrd_scan(void)
763 {
764 	int table_offset = 0;
765 	int table_index = 0;
766 	u32 table_length;
767 	struct acpi_table_header *table;
768 
769 	if (!acpi_tables_addr)
770 		return;
771 
772 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
773 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
774 					   ACPI_HEADER_SIZE);
775 		if (table_offset + table->length > all_tables_size) {
776 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
777 			WARN_ON(1);
778 			return;
779 		}
780 
781 		table_length = table->length;
782 
783 		/* Skip RSDT/XSDT which should only be used for override */
784 		if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
785 		    ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
786 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
787 			goto next_table;
788 		}
789 		/*
790 		 * Mark the table to avoid being used in
791 		 * acpi_table_initrd_override(). Though this is not possible
792 		 * because override is disabled in acpi_install_physical_table().
793 		 */
794 		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
795 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
796 			goto next_table;
797 		}
798 
799 		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
800 			table->signature, table->oem_id,
801 			table->oem_table_id);
802 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
803 		acpi_install_physical_table(acpi_tables_addr + table_offset);
804 next_table:
805 		table_offset += table_length;
806 		table_index++;
807 	}
808 }
809 #else
810 static acpi_status
811 acpi_table_initrd_override(struct acpi_table_header *existing_table,
812 			   acpi_physical_address *address,
813 			   u32 *table_length)
814 {
815 	*table_length = 0;
816 	*address = 0;
817 	return AE_OK;
818 }
819 
820 static void __init acpi_table_initrd_scan(void)
821 {
822 }
823 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
824 
825 acpi_status
826 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
827 				acpi_physical_address *address,
828 				u32 *table_length)
829 {
830 	return acpi_table_initrd_override(existing_table, address,
831 					  table_length);
832 }
833 
834 #ifdef CONFIG_ACPI_CUSTOM_DSDT
835 static void *amlcode __attribute__ ((weakref("AmlCode")));
836 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
837 #endif
838 
839 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
840 		       struct acpi_table_header **new_table)
841 {
842 	if (!existing_table || !new_table)
843 		return AE_BAD_PARAMETER;
844 
845 	*new_table = NULL;
846 
847 #ifdef CONFIG_ACPI_CUSTOM_DSDT
848 	if (!strncmp(existing_table->signature, "DSDT", 4)) {
849 		*new_table = (struct acpi_table_header *)&amlcode;
850 		if (!(*new_table))
851 			*new_table = (struct acpi_table_header *)&dsdt_amlcode;
852 	}
853 #endif
854 	if (*new_table != NULL)
855 		acpi_table_taint(existing_table);
856 	return AE_OK;
857 }
858 
859 /*
860  * acpi_locate_initial_tables()
861  *
862  * Get the RSDP, then find and checksum all the ACPI tables.
863  *
864  * result: initial_tables[] is initialized, and points to
865  * a list of ACPI tables.
866  */
867 int __init acpi_locate_initial_tables(void)
868 {
869 	acpi_status status;
870 
871 	if (acpi_verify_table_checksum) {
872 		pr_info("Early table checksum verification enabled\n");
873 		acpi_gbl_enable_table_validation = TRUE;
874 	} else {
875 		pr_info("Early table checksum verification disabled\n");
876 		acpi_gbl_enable_table_validation = FALSE;
877 	}
878 
879 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
880 	if (ACPI_FAILURE(status))
881 		return -EINVAL;
882 
883 	return 0;
884 }
885 
886 void __init acpi_reserve_initial_tables(void)
887 {
888 	int i;
889 
890 	for (i = 0; i < ACPI_MAX_TABLES; i++) {
891 		struct acpi_table_desc *table_desc = &initial_tables[i];
892 		u64 start = table_desc->address;
893 		u64 size = table_desc->length;
894 
895 		if (!start || !size)
896 			break;
897 
898 		pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
899 			table_desc->signature.ascii, start, start + size - 1);
900 
901 		memblock_reserve(start, size);
902 	}
903 }
904 
905 void __init acpi_table_init_complete(void)
906 {
907 	acpi_table_initrd_scan();
908 	check_multiple_madt();
909 }
910 
911 int __init acpi_table_init(void)
912 {
913 	int ret;
914 
915 	ret = acpi_locate_initial_tables();
916 	if (ret)
917 		return ret;
918 
919 	acpi_table_init_complete();
920 
921 	return 0;
922 }
923 
924 static int __init acpi_parse_apic_instance(char *str)
925 {
926 	if (!str)
927 		return -EINVAL;
928 
929 	if (kstrtoint(str, 0, &acpi_apic_instance))
930 		return -EINVAL;
931 
932 	pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
933 
934 	return 0;
935 }
936 early_param("acpi_apic_instance", acpi_parse_apic_instance);
937 
938 static int __init acpi_force_table_verification_setup(char *s)
939 {
940 	acpi_verify_table_checksum = true;
941 
942 	return 0;
943 }
944 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
945 
946 static int __init acpi_force_32bit_fadt_addr(char *s)
947 {
948 	pr_info("Forcing 32 Bit FADT addresses\n");
949 	acpi_gbl_use32_bit_fadt_addresses = TRUE;
950 
951 	return 0;
952 }
953 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
954