xref: /openbmc/linux/drivers/acpi/tables.c (revision 2326f3cd)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  acpi_tables.c - ACPI Boot-Time Table Parsing
4  *
5  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  */
7 
8 /* Uncomment next line to get verbose printout */
9 /* #define DEBUG */
10 #define pr_fmt(fmt) "ACPI: " fmt
11 
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/smp.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/irq.h>
18 #include <linux/errno.h>
19 #include <linux/acpi.h>
20 #include <linux/memblock.h>
21 #include <linux/earlycpio.h>
22 #include <linux/initrd.h>
23 #include <linux/security.h>
24 #include "internal.h"
25 
26 #ifdef CONFIG_ACPI_CUSTOM_DSDT
27 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
28 #endif
29 
30 #define ACPI_MAX_TABLES		128
31 
32 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
33 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
34 
35 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
36 
37 static int acpi_apic_instance __initdata;
38 
39 enum acpi_subtable_type {
40 	ACPI_SUBTABLE_COMMON,
41 	ACPI_SUBTABLE_HMAT,
42 	ACPI_SUBTABLE_PRMT,
43 };
44 
45 struct acpi_subtable_entry {
46 	union acpi_subtable_headers *hdr;
47 	enum acpi_subtable_type type;
48 };
49 
50 /*
51  * Disable table checksum verification for the early stage due to the size
52  * limitation of the current x86 early mapping implementation.
53  */
54 static bool acpi_verify_table_checksum __initdata = false;
55 
56 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
57 {
58 	if (!header)
59 		return;
60 
61 	switch (header->type) {
62 
63 	case ACPI_MADT_TYPE_LOCAL_APIC:
64 		{
65 			struct acpi_madt_local_apic *p =
66 			    (struct acpi_madt_local_apic *)header;
67 			pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
68 				 p->processor_id, p->id,
69 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
70 		}
71 		break;
72 
73 	case ACPI_MADT_TYPE_LOCAL_X2APIC:
74 		{
75 			struct acpi_madt_local_x2apic *p =
76 			    (struct acpi_madt_local_x2apic *)header;
77 			pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
78 				 p->local_apic_id, p->uid,
79 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
80 		}
81 		break;
82 
83 	case ACPI_MADT_TYPE_IO_APIC:
84 		{
85 			struct acpi_madt_io_apic *p =
86 			    (struct acpi_madt_io_apic *)header;
87 			pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
88 				 p->id, p->address, p->global_irq_base);
89 		}
90 		break;
91 
92 	case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
93 		{
94 			struct acpi_madt_interrupt_override *p =
95 			    (struct acpi_madt_interrupt_override *)header;
96 			pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
97 				p->bus, p->source_irq, p->global_irq,
98 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
99 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
100 			if (p->inti_flags  &
101 			    ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
102 				pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
103 					p->inti_flags  &
104 					~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
105 		}
106 		break;
107 
108 	case ACPI_MADT_TYPE_NMI_SOURCE:
109 		{
110 			struct acpi_madt_nmi_source *p =
111 			    (struct acpi_madt_nmi_source *)header;
112 			pr_info("NMI_SRC (%s %s global_irq %d)\n",
113 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
114 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
115 				p->global_irq);
116 		}
117 		break;
118 
119 	case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
120 		{
121 			struct acpi_madt_local_apic_nmi *p =
122 			    (struct acpi_madt_local_apic_nmi *)header;
123 			pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
124 				p->processor_id,
125 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK	],
126 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
127 				p->lint);
128 		}
129 		break;
130 
131 	case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
132 		{
133 			u16 polarity, trigger;
134 			struct acpi_madt_local_x2apic_nmi *p =
135 			    (struct acpi_madt_local_x2apic_nmi *)header;
136 
137 			polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
138 			trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
139 
140 			pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
141 				p->uid,
142 				mps_inti_flags_polarity[polarity],
143 				mps_inti_flags_trigger[trigger],
144 				p->lint);
145 		}
146 		break;
147 
148 	case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
149 		{
150 			struct acpi_madt_local_apic_override *p =
151 			    (struct acpi_madt_local_apic_override *)header;
152 			pr_info("LAPIC_ADDR_OVR (address[%p])\n",
153 				(void *)(unsigned long)p->address);
154 		}
155 		break;
156 
157 	case ACPI_MADT_TYPE_IO_SAPIC:
158 		{
159 			struct acpi_madt_io_sapic *p =
160 			    (struct acpi_madt_io_sapic *)header;
161 			pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
162 				 p->id, (void *)(unsigned long)p->address,
163 				 p->global_irq_base);
164 		}
165 		break;
166 
167 	case ACPI_MADT_TYPE_LOCAL_SAPIC:
168 		{
169 			struct acpi_madt_local_sapic *p =
170 			    (struct acpi_madt_local_sapic *)header;
171 			pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
172 				 p->processor_id, p->id, p->eid,
173 				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
174 		}
175 		break;
176 
177 	case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
178 		{
179 			struct acpi_madt_interrupt_source *p =
180 			    (struct acpi_madt_interrupt_source *)header;
181 			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",
182 				mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
183 				mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
184 				p->type, p->id, p->eid, p->io_sapic_vector,
185 				p->global_irq);
186 		}
187 		break;
188 
189 	case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
190 		{
191 			struct acpi_madt_generic_interrupt *p =
192 				(struct acpi_madt_generic_interrupt *)header;
193 			pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
194 				 p->uid, p->base_address,
195 				 p->arm_mpidr,
196 				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
197 
198 		}
199 		break;
200 
201 	case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
202 		{
203 			struct acpi_madt_generic_distributor *p =
204 				(struct acpi_madt_generic_distributor *)header;
205 			pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
206 				 p->gic_id, p->base_address,
207 				 p->global_irq_base);
208 		}
209 		break;
210 
211 	default:
212 		pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
213 			header->type);
214 		break;
215 	}
216 }
217 
218 static unsigned long __init
219 acpi_get_entry_type(struct acpi_subtable_entry *entry)
220 {
221 	switch (entry->type) {
222 	case ACPI_SUBTABLE_COMMON:
223 		return entry->hdr->common.type;
224 	case ACPI_SUBTABLE_HMAT:
225 		return entry->hdr->hmat.type;
226 	case ACPI_SUBTABLE_PRMT:
227 		return 0;
228 	}
229 	return 0;
230 }
231 
232 static unsigned long __init
233 acpi_get_entry_length(struct acpi_subtable_entry *entry)
234 {
235 	switch (entry->type) {
236 	case ACPI_SUBTABLE_COMMON:
237 		return entry->hdr->common.length;
238 	case ACPI_SUBTABLE_HMAT:
239 		return entry->hdr->hmat.length;
240 	case ACPI_SUBTABLE_PRMT:
241 		return entry->hdr->prmt.length;
242 	}
243 	return 0;
244 }
245 
246 static unsigned long __init
247 acpi_get_subtable_header_length(struct acpi_subtable_entry *entry)
248 {
249 	switch (entry->type) {
250 	case ACPI_SUBTABLE_COMMON:
251 		return sizeof(entry->hdr->common);
252 	case ACPI_SUBTABLE_HMAT:
253 		return sizeof(entry->hdr->hmat);
254 	case ACPI_SUBTABLE_PRMT:
255 		return sizeof(entry->hdr->prmt);
256 	}
257 	return 0;
258 }
259 
260 static enum acpi_subtable_type __init
261 acpi_get_subtable_type(char *id)
262 {
263 	if (strncmp(id, ACPI_SIG_HMAT, 4) == 0)
264 		return ACPI_SUBTABLE_HMAT;
265 	if (strncmp(id, ACPI_SIG_PRMT, 4) == 0)
266 		return ACPI_SUBTABLE_PRMT;
267 	return ACPI_SUBTABLE_COMMON;
268 }
269 
270 /**
271  * acpi_parse_entries_array - for each proc_num find a suitable subtable
272  *
273  * @id: table id (for debugging purposes)
274  * @table_size: size of the root table
275  * @table_header: where does the table start?
276  * @proc: array of acpi_subtable_proc struct containing entry id
277  *        and associated handler with it
278  * @proc_num: how big proc is?
279  * @max_entries: how many entries can we process?
280  *
281  * For each proc_num find a subtable with proc->id and run proc->handler
282  * on it. Assumption is that there's only single handler for particular
283  * entry id.
284  *
285  * The table_size is not the size of the complete ACPI table (the length
286  * field in the header struct), but only the size of the root table; i.e.,
287  * the offset from the very first byte of the complete ACPI table, to the
288  * first byte of the very first subtable.
289  *
290  * On success returns sum of all matching entries for all proc handlers.
291  * Otherwise, -ENODEV or -EINVAL is returned.
292  */
293 static int __init acpi_parse_entries_array(char *id, unsigned long table_size,
294 		struct acpi_table_header *table_header,
295 		struct acpi_subtable_proc *proc, int proc_num,
296 		unsigned int max_entries)
297 {
298 	struct acpi_subtable_entry entry;
299 	unsigned long table_end, subtable_len, entry_len;
300 	int count = 0;
301 	int errs = 0;
302 	int i;
303 
304 	table_end = (unsigned long)table_header + table_header->length;
305 
306 	/* Parse all entries looking for a match. */
307 
308 	entry.type = acpi_get_subtable_type(id);
309 	entry.hdr = (union acpi_subtable_headers *)
310 	    ((unsigned long)table_header + table_size);
311 	subtable_len = acpi_get_subtable_header_length(&entry);
312 
313 	while (((unsigned long)entry.hdr) + subtable_len  < table_end) {
314 		if (max_entries && count >= max_entries)
315 			break;
316 
317 		for (i = 0; i < proc_num; i++) {
318 			if (acpi_get_entry_type(&entry) != proc[i].id)
319 				continue;
320 			if (!proc[i].handler ||
321 			     (!errs && proc[i].handler(entry.hdr, table_end))) {
322 				errs++;
323 				continue;
324 			}
325 
326 			proc[i].count++;
327 			break;
328 		}
329 		if (i != proc_num)
330 			count++;
331 
332 		/*
333 		 * If entry->length is 0, break from this loop to avoid
334 		 * infinite loop.
335 		 */
336 		entry_len = acpi_get_entry_length(&entry);
337 		if (entry_len == 0) {
338 			pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
339 			return -EINVAL;
340 		}
341 
342 		entry.hdr = (union acpi_subtable_headers *)
343 		    ((unsigned long)entry.hdr + entry_len);
344 	}
345 
346 	if (max_entries && count > max_entries) {
347 		pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
348 			id, proc->id, count);
349 	}
350 
351 	return errs ? -EINVAL : count;
352 }
353 
354 int __init acpi_table_parse_entries_array(char *id,
355 			 unsigned long table_size,
356 			 struct acpi_subtable_proc *proc, int proc_num,
357 			 unsigned int max_entries)
358 {
359 	struct acpi_table_header *table_header = NULL;
360 	int count;
361 	u32 instance = 0;
362 
363 	if (acpi_disabled)
364 		return -ENODEV;
365 
366 	if (!id)
367 		return -EINVAL;
368 
369 	if (!table_size)
370 		return -EINVAL;
371 
372 	if (!strncmp(id, ACPI_SIG_MADT, 4))
373 		instance = acpi_apic_instance;
374 
375 	acpi_get_table(id, instance, &table_header);
376 	if (!table_header) {
377 		pr_warn("%4.4s not present\n", id);
378 		return -ENODEV;
379 	}
380 
381 	count = acpi_parse_entries_array(id, table_size, table_header,
382 			proc, proc_num, max_entries);
383 
384 	acpi_put_table(table_header);
385 	return count;
386 }
387 
388 int __init acpi_table_parse_entries(char *id,
389 			unsigned long table_size,
390 			int entry_id,
391 			acpi_tbl_entry_handler handler,
392 			unsigned int max_entries)
393 {
394 	struct acpi_subtable_proc proc = {
395 		.id		= entry_id,
396 		.handler	= handler,
397 	};
398 
399 	return acpi_table_parse_entries_array(id, table_size, &proc, 1,
400 						max_entries);
401 }
402 
403 int __init acpi_table_parse_madt(enum acpi_madt_type id,
404 		      acpi_tbl_entry_handler handler, unsigned int max_entries)
405 {
406 	return acpi_table_parse_entries(ACPI_SIG_MADT,
407 					    sizeof(struct acpi_table_madt), id,
408 					    handler, max_entries);
409 }
410 
411 /**
412  * acpi_table_parse - find table with @id, run @handler on it
413  * @id: table id to find
414  * @handler: handler to run
415  *
416  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
417  * run @handler on it.
418  *
419  * Return 0 if table found, -errno if not.
420  */
421 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
422 {
423 	struct acpi_table_header *table = NULL;
424 
425 	if (acpi_disabled)
426 		return -ENODEV;
427 
428 	if (!id || !handler)
429 		return -EINVAL;
430 
431 	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
432 		acpi_get_table(id, acpi_apic_instance, &table);
433 	else
434 		acpi_get_table(id, 0, &table);
435 
436 	if (table) {
437 		handler(table);
438 		acpi_put_table(table);
439 		return 0;
440 	} else
441 		return -ENODEV;
442 }
443 
444 /*
445  * The BIOS is supposed to supply a single APIC/MADT,
446  * but some report two.  Provide a knob to use either.
447  * (don't you wish instance 0 and 1 were not the same?)
448  */
449 static void __init check_multiple_madt(void)
450 {
451 	struct acpi_table_header *table = NULL;
452 
453 	acpi_get_table(ACPI_SIG_MADT, 2, &table);
454 	if (table) {
455 		pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
456 			acpi_apic_instance);
457 		pr_warn("If \"acpi_apic_instance=%d\" works better, "
458 			"notify linux-acpi@vger.kernel.org\n",
459 			acpi_apic_instance ? 0 : 2);
460 		acpi_put_table(table);
461 
462 	} else
463 		acpi_apic_instance = 0;
464 
465 	return;
466 }
467 
468 static void acpi_table_taint(struct acpi_table_header *table)
469 {
470 	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
471 		table->signature, table->oem_table_id);
472 	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
473 }
474 
475 #ifdef CONFIG_ACPI_TABLE_UPGRADE
476 static u64 acpi_tables_addr;
477 static int all_tables_size;
478 
479 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
480 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
481 {
482 	u8 sum = 0;
483 	u8 *end = buffer + length;
484 
485 	while (buffer < end)
486 		sum = (u8) (sum + *(buffer++));
487 	return sum;
488 }
489 
490 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
491 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
492 	ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
493 	ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
494 	ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
495 	ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
496 	ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
497 	ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
498 	ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
499 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
500 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
501 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
502 	ACPI_SIG_NHLT };
503 
504 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
505 
506 #define NR_ACPI_INITRD_TABLES 64
507 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
508 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
509 
510 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
511 
512 void __init acpi_table_upgrade(void)
513 {
514 	void *data;
515 	size_t size;
516 	int sig, no, table_nr = 0, total_offset = 0;
517 	long offset = 0;
518 	struct acpi_table_header *table;
519 	char cpio_path[32] = "kernel/firmware/acpi/";
520 	struct cpio_data file;
521 
522 	if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
523 		data = __initramfs_start;
524 		size = __initramfs_size;
525 	} else {
526 		data = (void *)initrd_start;
527 		size = initrd_end - initrd_start;
528 	}
529 
530 	if (data == NULL || size == 0)
531 		return;
532 
533 	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
534 		file = find_cpio_data(cpio_path, data, size, &offset);
535 		if (!file.data)
536 			break;
537 
538 		data += offset;
539 		size -= offset;
540 
541 		if (file.size < sizeof(struct acpi_table_header)) {
542 			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
543 				cpio_path, file.name);
544 			continue;
545 		}
546 
547 		table = file.data;
548 
549 		for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
550 			if (!memcmp(table->signature, table_sigs[sig], 4))
551 				break;
552 
553 		if (sig >= ARRAY_SIZE(table_sigs)) {
554 			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
555 				cpio_path, file.name);
556 			continue;
557 		}
558 		if (file.size != table->length) {
559 			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
560 				cpio_path, file.name);
561 			continue;
562 		}
563 		if (acpi_table_checksum(file.data, table->length)) {
564 			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
565 				cpio_path, file.name);
566 			continue;
567 		}
568 
569 		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
570 			table->signature, cpio_path, file.name, table->length);
571 
572 		all_tables_size += table->length;
573 		acpi_initrd_files[table_nr].data = file.data;
574 		acpi_initrd_files[table_nr].size = file.size;
575 		table_nr++;
576 	}
577 	if (table_nr == 0)
578 		return;
579 
580 	if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
581 		pr_notice("kernel is locked down, ignoring table override\n");
582 		return;
583 	}
584 
585 	acpi_tables_addr =
586 		memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
587 					  0, ACPI_TABLE_UPGRADE_MAX_PHYS);
588 	if (!acpi_tables_addr) {
589 		WARN_ON(1);
590 		return;
591 	}
592 	/*
593 	 * Only calling e820_add_reserve does not work and the
594 	 * tables are invalid (memory got used) later.
595 	 * memblock_reserve works as expected and the tables won't get modified.
596 	 * But it's not enough on X86 because ioremap will
597 	 * complain later (used by acpi_os_map_memory) that the pages
598 	 * that should get mapped are not marked "reserved".
599 	 * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
600 	 * works fine.
601 	 */
602 	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
603 
604 	/*
605 	 * early_ioremap only can remap 256k one time. If we map all
606 	 * tables one time, we will hit the limit. Need to map chunks
607 	 * one by one during copying the same as that in relocate_initrd().
608 	 */
609 	for (no = 0; no < table_nr; no++) {
610 		unsigned char *src_p = acpi_initrd_files[no].data;
611 		phys_addr_t size = acpi_initrd_files[no].size;
612 		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
613 		phys_addr_t slop, clen;
614 		char *dest_p;
615 
616 		total_offset += size;
617 
618 		while (size) {
619 			slop = dest_addr & ~PAGE_MASK;
620 			clen = size;
621 			if (clen > MAP_CHUNK_SIZE - slop)
622 				clen = MAP_CHUNK_SIZE - slop;
623 			dest_p = early_memremap(dest_addr & PAGE_MASK,
624 						clen + slop);
625 			memcpy(dest_p + slop, src_p, clen);
626 			early_memunmap(dest_p, clen + slop);
627 			src_p += clen;
628 			dest_addr += clen;
629 			size -= clen;
630 		}
631 	}
632 }
633 
634 static acpi_status
635 acpi_table_initrd_override(struct acpi_table_header *existing_table,
636 			   acpi_physical_address *address, u32 *length)
637 {
638 	int table_offset = 0;
639 	int table_index = 0;
640 	struct acpi_table_header *table;
641 	u32 table_length;
642 
643 	*length = 0;
644 	*address = 0;
645 	if (!acpi_tables_addr)
646 		return AE_OK;
647 
648 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
649 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
650 					   ACPI_HEADER_SIZE);
651 		if (table_offset + table->length > all_tables_size) {
652 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
653 			WARN_ON(1);
654 			return AE_OK;
655 		}
656 
657 		table_length = table->length;
658 
659 		/* Only override tables matched */
660 		if (memcmp(existing_table->signature, table->signature, 4) ||
661 		    memcmp(table->oem_id, existing_table->oem_id,
662 			   ACPI_OEM_ID_SIZE) ||
663 		    memcmp(table->oem_table_id, existing_table->oem_table_id,
664 			   ACPI_OEM_TABLE_ID_SIZE)) {
665 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
666 			goto next_table;
667 		}
668 		/*
669 		 * Mark the table to avoid being used in
670 		 * acpi_table_initrd_scan() and check the revision.
671 		 */
672 		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
673 		    existing_table->oem_revision >= table->oem_revision) {
674 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
675 			goto next_table;
676 		}
677 
678 		*length = table_length;
679 		*address = acpi_tables_addr + table_offset;
680 		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
681 			table->signature, table->oem_id,
682 			table->oem_table_id);
683 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
684 		break;
685 
686 next_table:
687 		table_offset += table_length;
688 		table_index++;
689 	}
690 	return AE_OK;
691 }
692 
693 static void __init acpi_table_initrd_scan(void)
694 {
695 	int table_offset = 0;
696 	int table_index = 0;
697 	u32 table_length;
698 	struct acpi_table_header *table;
699 
700 	if (!acpi_tables_addr)
701 		return;
702 
703 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
704 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
705 					   ACPI_HEADER_SIZE);
706 		if (table_offset + table->length > all_tables_size) {
707 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
708 			WARN_ON(1);
709 			return;
710 		}
711 
712 		table_length = table->length;
713 
714 		/* Skip RSDT/XSDT which should only be used for override */
715 		if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
716 		    ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
717 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
718 			goto next_table;
719 		}
720 		/*
721 		 * Mark the table to avoid being used in
722 		 * acpi_table_initrd_override(). Though this is not possible
723 		 * because override is disabled in acpi_install_table().
724 		 */
725 		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
726 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
727 			goto next_table;
728 		}
729 
730 		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
731 			table->signature, table->oem_id,
732 			table->oem_table_id);
733 		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
734 		acpi_install_table(acpi_tables_addr + table_offset, TRUE);
735 next_table:
736 		table_offset += table_length;
737 		table_index++;
738 	}
739 }
740 #else
741 static acpi_status
742 acpi_table_initrd_override(struct acpi_table_header *existing_table,
743 			   acpi_physical_address *address,
744 			   u32 *table_length)
745 {
746 	*table_length = 0;
747 	*address = 0;
748 	return AE_OK;
749 }
750 
751 static void __init acpi_table_initrd_scan(void)
752 {
753 }
754 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
755 
756 acpi_status
757 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
758 				acpi_physical_address *address,
759 				u32 *table_length)
760 {
761 	return acpi_table_initrd_override(existing_table, address,
762 					  table_length);
763 }
764 
765 #ifdef CONFIG_ACPI_CUSTOM_DSDT
766 static void *amlcode __attribute__ ((weakref("AmlCode")));
767 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
768 #endif
769 
770 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
771 		       struct acpi_table_header **new_table)
772 {
773 	if (!existing_table || !new_table)
774 		return AE_BAD_PARAMETER;
775 
776 	*new_table = NULL;
777 
778 #ifdef CONFIG_ACPI_CUSTOM_DSDT
779 	if (!strncmp(existing_table->signature, "DSDT", 4)) {
780 		*new_table = (struct acpi_table_header *)&amlcode;
781 		if (!(*new_table))
782 			*new_table = (struct acpi_table_header *)&dsdt_amlcode;
783 	}
784 #endif
785 	if (*new_table != NULL)
786 		acpi_table_taint(existing_table);
787 	return AE_OK;
788 }
789 
790 /*
791  * acpi_locate_initial_tables()
792  *
793  * find RSDP, find and checksum SDT/XSDT.
794  * checksum all tables, print SDT/XSDT
795  *
796  * result: sdt_entry[] is initialized
797  */
798 
799 int __init acpi_locate_initial_tables(void)
800 {
801 	acpi_status status;
802 
803 	if (acpi_verify_table_checksum) {
804 		pr_info("Early table checksum verification enabled\n");
805 		acpi_gbl_enable_table_validation = TRUE;
806 	} else {
807 		pr_info("Early table checksum verification disabled\n");
808 		acpi_gbl_enable_table_validation = FALSE;
809 	}
810 
811 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
812 	if (ACPI_FAILURE(status))
813 		return -EINVAL;
814 
815 	return 0;
816 }
817 
818 void __init acpi_reserve_initial_tables(void)
819 {
820 	int i;
821 
822 	for (i = 0; i < ACPI_MAX_TABLES; i++) {
823 		struct acpi_table_desc *table_desc = &initial_tables[i];
824 		u64 start = table_desc->address;
825 		u64 size = table_desc->length;
826 
827 		if (!start || !size)
828 			break;
829 
830 		pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
831 			table_desc->signature.ascii, start, start + size - 1);
832 
833 		memblock_reserve(start, size);
834 	}
835 }
836 
837 void __init acpi_table_init_complete(void)
838 {
839 	acpi_table_initrd_scan();
840 	check_multiple_madt();
841 }
842 
843 int __init acpi_table_init(void)
844 {
845 	int ret;
846 
847 	ret = acpi_locate_initial_tables();
848 	if (ret)
849 		return ret;
850 
851 	acpi_table_init_complete();
852 
853 	return 0;
854 }
855 
856 static int __init acpi_parse_apic_instance(char *str)
857 {
858 	if (!str)
859 		return -EINVAL;
860 
861 	if (kstrtoint(str, 0, &acpi_apic_instance))
862 		return -EINVAL;
863 
864 	pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
865 
866 	return 0;
867 }
868 early_param("acpi_apic_instance", acpi_parse_apic_instance);
869 
870 static int __init acpi_force_table_verification_setup(char *s)
871 {
872 	acpi_verify_table_checksum = true;
873 
874 	return 0;
875 }
876 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
877 
878 static int __init acpi_force_32bit_fadt_addr(char *s)
879 {
880 	pr_info("Forcing 32 Bit FADT addresses\n");
881 	acpi_gbl_use32_bit_fadt_addresses = TRUE;
882 
883 	return 0;
884 }
885 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);
886