xref: /linux/arch/x86/platform/efi/efi.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*
2  * Common EFI (Extensible Firmware Interface) support functions
3  * Based on Extensible Firmware Interface Specification version 1.0
4  *
5  * Copyright (C) 1999 VA Linux Systems
6  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
7  * Copyright (C) 1999-2002 Hewlett-Packard Co.
8  *	David Mosberger-Tang <davidm@hpl.hp.com>
9  *	Stephane Eranian <eranian@hpl.hp.com>
10  * Copyright (C) 2005-2008 Intel Co.
11  *	Fenghua Yu <fenghua.yu@intel.com>
12  *	Bibo Mao <bibo.mao@intel.com>
13  *	Chandramouli Narayanan <mouli@linux.intel.com>
14  *	Huang Ying <ying.huang@intel.com>
15  *
16  * Copied from efi_32.c to eliminate the duplicated code between EFI
17  * 32/64 support code. --ying 2007-10-26
18  *
19  * All EFI Runtime Services are not implemented yet as EFI only
20  * supports physical mode addressing on SoftSDV. This is to be fixed
21  * in a future version.  --drummond 1999-07-20
22  *
23  * Implemented EFI runtime services and virtual mode calls.  --davidm
24  *
25  * Goutham Rao: <goutham.rao@intel.com>
26  *	Skip non-WB memory and ignore empty memory ranges.
27  */
28 
29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30 
31 #include <linux/kernel.h>
32 #include <linux/init.h>
33 #include <linux/efi.h>
34 #include <linux/efi-bgrt.h>
35 #include <linux/export.h>
36 #include <linux/bootmem.h>
37 #include <linux/memblock.h>
38 #include <linux/spinlock.h>
39 #include <linux/uaccess.h>
40 #include <linux/time.h>
41 #include <linux/io.h>
42 #include <linux/reboot.h>
43 #include <linux/bcd.h>
44 
45 #include <asm/setup.h>
46 #include <asm/efi.h>
47 #include <asm/time.h>
48 #include <asm/cacheflush.h>
49 #include <asm/tlbflush.h>
50 #include <asm/x86_init.h>
51 
52 #define EFI_DEBUG	1
53 
54 int efi_enabled;
55 EXPORT_SYMBOL(efi_enabled);
56 
57 struct efi __read_mostly efi = {
58 	.mps        = EFI_INVALID_TABLE_ADDR,
59 	.acpi       = EFI_INVALID_TABLE_ADDR,
60 	.acpi20     = EFI_INVALID_TABLE_ADDR,
61 	.smbios     = EFI_INVALID_TABLE_ADDR,
62 	.sal_systab = EFI_INVALID_TABLE_ADDR,
63 	.boot_info  = EFI_INVALID_TABLE_ADDR,
64 	.hcdp       = EFI_INVALID_TABLE_ADDR,
65 	.uga        = EFI_INVALID_TABLE_ADDR,
66 	.uv_systab  = EFI_INVALID_TABLE_ADDR,
67 };
68 EXPORT_SYMBOL(efi);
69 
70 struct efi_memory_map memmap;
71 
72 bool efi_64bit;
73 
74 static struct efi efi_phys __initdata;
75 static efi_system_table_t efi_systab __initdata;
76 
77 static inline bool efi_is_native(void)
78 {
79 	return IS_ENABLED(CONFIG_X86_64) == efi_64bit;
80 }
81 
82 static int __init setup_noefi(char *arg)
83 {
84 	efi_enabled = 0;
85 	return 0;
86 }
87 early_param("noefi", setup_noefi);
88 
89 int add_efi_memmap;
90 EXPORT_SYMBOL(add_efi_memmap);
91 
92 static int __init setup_add_efi_memmap(char *arg)
93 {
94 	add_efi_memmap = 1;
95 	return 0;
96 }
97 early_param("add_efi_memmap", setup_add_efi_memmap);
98 
99 
100 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
101 {
102 	unsigned long flags;
103 	efi_status_t status;
104 
105 	spin_lock_irqsave(&rtc_lock, flags);
106 	status = efi_call_virt2(get_time, tm, tc);
107 	spin_unlock_irqrestore(&rtc_lock, flags);
108 	return status;
109 }
110 
111 static efi_status_t virt_efi_set_time(efi_time_t *tm)
112 {
113 	unsigned long flags;
114 	efi_status_t status;
115 
116 	spin_lock_irqsave(&rtc_lock, flags);
117 	status = efi_call_virt1(set_time, tm);
118 	spin_unlock_irqrestore(&rtc_lock, flags);
119 	return status;
120 }
121 
122 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
123 					     efi_bool_t *pending,
124 					     efi_time_t *tm)
125 {
126 	unsigned long flags;
127 	efi_status_t status;
128 
129 	spin_lock_irqsave(&rtc_lock, flags);
130 	status = efi_call_virt3(get_wakeup_time,
131 				enabled, pending, tm);
132 	spin_unlock_irqrestore(&rtc_lock, flags);
133 	return status;
134 }
135 
136 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
137 {
138 	unsigned long flags;
139 	efi_status_t status;
140 
141 	spin_lock_irqsave(&rtc_lock, flags);
142 	status = efi_call_virt2(set_wakeup_time,
143 				enabled, tm);
144 	spin_unlock_irqrestore(&rtc_lock, flags);
145 	return status;
146 }
147 
148 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
149 					  efi_guid_t *vendor,
150 					  u32 *attr,
151 					  unsigned long *data_size,
152 					  void *data)
153 {
154 	return efi_call_virt5(get_variable,
155 			      name, vendor, attr,
156 			      data_size, data);
157 }
158 
159 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
160 					       efi_char16_t *name,
161 					       efi_guid_t *vendor)
162 {
163 	return efi_call_virt3(get_next_variable,
164 			      name_size, name, vendor);
165 }
166 
167 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
168 					  efi_guid_t *vendor,
169 					  u32 attr,
170 					  unsigned long data_size,
171 					  void *data)
172 {
173 	return efi_call_virt5(set_variable,
174 			      name, vendor, attr,
175 			      data_size, data);
176 }
177 
178 static efi_status_t virt_efi_query_variable_info(u32 attr,
179 						 u64 *storage_space,
180 						 u64 *remaining_space,
181 						 u64 *max_variable_size)
182 {
183 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
184 		return EFI_UNSUPPORTED;
185 
186 	return efi_call_virt4(query_variable_info, attr, storage_space,
187 			      remaining_space, max_variable_size);
188 }
189 
190 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
191 {
192 	return efi_call_virt1(get_next_high_mono_count, count);
193 }
194 
195 static void virt_efi_reset_system(int reset_type,
196 				  efi_status_t status,
197 				  unsigned long data_size,
198 				  efi_char16_t *data)
199 {
200 	efi_call_virt4(reset_system, reset_type, status,
201 		       data_size, data);
202 }
203 
204 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
205 					    unsigned long count,
206 					    unsigned long sg_list)
207 {
208 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
209 		return EFI_UNSUPPORTED;
210 
211 	return efi_call_virt3(update_capsule, capsules, count, sg_list);
212 }
213 
214 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
215 						unsigned long count,
216 						u64 *max_size,
217 						int *reset_type)
218 {
219 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
220 		return EFI_UNSUPPORTED;
221 
222 	return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
223 			      reset_type);
224 }
225 
226 static efi_status_t __init phys_efi_set_virtual_address_map(
227 	unsigned long memory_map_size,
228 	unsigned long descriptor_size,
229 	u32 descriptor_version,
230 	efi_memory_desc_t *virtual_map)
231 {
232 	efi_status_t status;
233 
234 	efi_call_phys_prelog();
235 	status = efi_call_phys4(efi_phys.set_virtual_address_map,
236 				memory_map_size, descriptor_size,
237 				descriptor_version, virtual_map);
238 	efi_call_phys_epilog();
239 	return status;
240 }
241 
242 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
243 					     efi_time_cap_t *tc)
244 {
245 	unsigned long flags;
246 	efi_status_t status;
247 
248 	spin_lock_irqsave(&rtc_lock, flags);
249 	efi_call_phys_prelog();
250 	status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
251 				virt_to_phys(tc));
252 	efi_call_phys_epilog();
253 	spin_unlock_irqrestore(&rtc_lock, flags);
254 	return status;
255 }
256 
257 int efi_set_rtc_mmss(unsigned long nowtime)
258 {
259 	int real_seconds, real_minutes;
260 	efi_status_t 	status;
261 	efi_time_t 	eft;
262 	efi_time_cap_t 	cap;
263 
264 	status = efi.get_time(&eft, &cap);
265 	if (status != EFI_SUCCESS) {
266 		pr_err("Oops: efitime: can't read time!\n");
267 		return -1;
268 	}
269 
270 	real_seconds = nowtime % 60;
271 	real_minutes = nowtime / 60;
272 	if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
273 		real_minutes += 30;
274 	real_minutes %= 60;
275 	eft.minute = real_minutes;
276 	eft.second = real_seconds;
277 
278 	status = efi.set_time(&eft);
279 	if (status != EFI_SUCCESS) {
280 		pr_err("Oops: efitime: can't write time!\n");
281 		return -1;
282 	}
283 	return 0;
284 }
285 
286 unsigned long efi_get_time(void)
287 {
288 	efi_status_t status;
289 	efi_time_t eft;
290 	efi_time_cap_t cap;
291 
292 	status = efi.get_time(&eft, &cap);
293 	if (status != EFI_SUCCESS)
294 		pr_err("Oops: efitime: can't read time!\n");
295 
296 	return mktime(eft.year, eft.month, eft.day, eft.hour,
297 		      eft.minute, eft.second);
298 }
299 
300 /*
301  * Tell the kernel about the EFI memory map.  This might include
302  * more than the max 128 entries that can fit in the e820 legacy
303  * (zeropage) memory map.
304  */
305 
306 static void __init do_add_efi_memmap(void)
307 {
308 	void *p;
309 
310 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
311 		efi_memory_desc_t *md = p;
312 		unsigned long long start = md->phys_addr;
313 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
314 		int e820_type;
315 
316 		switch (md->type) {
317 		case EFI_LOADER_CODE:
318 		case EFI_LOADER_DATA:
319 		case EFI_BOOT_SERVICES_CODE:
320 		case EFI_BOOT_SERVICES_DATA:
321 		case EFI_CONVENTIONAL_MEMORY:
322 			if (md->attribute & EFI_MEMORY_WB)
323 				e820_type = E820_RAM;
324 			else
325 				e820_type = E820_RESERVED;
326 			break;
327 		case EFI_ACPI_RECLAIM_MEMORY:
328 			e820_type = E820_ACPI;
329 			break;
330 		case EFI_ACPI_MEMORY_NVS:
331 			e820_type = E820_NVS;
332 			break;
333 		case EFI_UNUSABLE_MEMORY:
334 			e820_type = E820_UNUSABLE;
335 			break;
336 		default:
337 			/*
338 			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
339 			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
340 			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
341 			 */
342 			e820_type = E820_RESERVED;
343 			break;
344 		}
345 		e820_add_region(start, size, e820_type);
346 	}
347 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
348 }
349 
350 int __init efi_memblock_x86_reserve_range(void)
351 {
352 	unsigned long pmap;
353 
354 #ifdef CONFIG_X86_32
355 	/* Can't handle data above 4GB at this time */
356 	if (boot_params.efi_info.efi_memmap_hi) {
357 		pr_err("Memory map is above 4GB, disabling EFI.\n");
358 		return -EINVAL;
359 	}
360 	pmap = boot_params.efi_info.efi_memmap;
361 #else
362 	pmap = (boot_params.efi_info.efi_memmap |
363 		((__u64)boot_params.efi_info.efi_memmap_hi<<32));
364 #endif
365 	memmap.phys_map = (void *)pmap;
366 	memmap.nr_map = boot_params.efi_info.efi_memmap_size /
367 		boot_params.efi_info.efi_memdesc_size;
368 	memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
369 	memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
370 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
371 
372 	return 0;
373 }
374 
375 #if EFI_DEBUG
376 static void __init print_efi_memmap(void)
377 {
378 	efi_memory_desc_t *md;
379 	void *p;
380 	int i;
381 
382 	for (p = memmap.map, i = 0;
383 	     p < memmap.map_end;
384 	     p += memmap.desc_size, i++) {
385 		md = p;
386 		pr_info("mem%02u: type=%u, attr=0x%llx, "
387 			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
388 			i, md->type, md->attribute, md->phys_addr,
389 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
390 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
391 	}
392 }
393 #endif  /*  EFI_DEBUG  */
394 
395 void __init efi_reserve_boot_services(void)
396 {
397 	void *p;
398 
399 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
400 		efi_memory_desc_t *md = p;
401 		u64 start = md->phys_addr;
402 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
403 
404 		if (md->type != EFI_BOOT_SERVICES_CODE &&
405 		    md->type != EFI_BOOT_SERVICES_DATA)
406 			continue;
407 		/* Only reserve where possible:
408 		 * - Not within any already allocated areas
409 		 * - Not over any memory area (really needed, if above?)
410 		 * - Not within any part of the kernel
411 		 * - Not the bios reserved area
412 		*/
413 		if ((start+size >= virt_to_phys(_text)
414 				&& start <= virt_to_phys(_end)) ||
415 			!e820_all_mapped(start, start+size, E820_RAM) ||
416 			memblock_is_region_reserved(start, size)) {
417 			/* Could not reserve, skip it */
418 			md->num_pages = 0;
419 			memblock_dbg("Could not reserve boot range "
420 					"[0x%010llx-0x%010llx]\n",
421 						start, start+size-1);
422 		} else
423 			memblock_reserve(start, size);
424 	}
425 }
426 
427 void __init efi_unmap_memmap(void)
428 {
429 	if (memmap.map) {
430 		early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
431 		memmap.map = NULL;
432 	}
433 }
434 
435 void __init efi_free_boot_services(void)
436 {
437 	void *p;
438 
439 	if (!efi_is_native())
440 		return;
441 
442 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
443 		efi_memory_desc_t *md = p;
444 		unsigned long long start = md->phys_addr;
445 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
446 
447 		if (md->type != EFI_BOOT_SERVICES_CODE &&
448 		    md->type != EFI_BOOT_SERVICES_DATA)
449 			continue;
450 
451 		/* Could not reserve boot area */
452 		if (!size)
453 			continue;
454 
455 		free_bootmem_late(start, size);
456 	}
457 
458 	efi_unmap_memmap();
459 }
460 
461 static int __init efi_systab_init(void *phys)
462 {
463 	if (efi_64bit) {
464 		efi_system_table_64_t *systab64;
465 		u64 tmp = 0;
466 
467 		systab64 = early_ioremap((unsigned long)phys,
468 					 sizeof(*systab64));
469 		if (systab64 == NULL) {
470 			pr_err("Couldn't map the system table!\n");
471 			return -ENOMEM;
472 		}
473 
474 		efi_systab.hdr = systab64->hdr;
475 		efi_systab.fw_vendor = systab64->fw_vendor;
476 		tmp |= systab64->fw_vendor;
477 		efi_systab.fw_revision = systab64->fw_revision;
478 		efi_systab.con_in_handle = systab64->con_in_handle;
479 		tmp |= systab64->con_in_handle;
480 		efi_systab.con_in = systab64->con_in;
481 		tmp |= systab64->con_in;
482 		efi_systab.con_out_handle = systab64->con_out_handle;
483 		tmp |= systab64->con_out_handle;
484 		efi_systab.con_out = systab64->con_out;
485 		tmp |= systab64->con_out;
486 		efi_systab.stderr_handle = systab64->stderr_handle;
487 		tmp |= systab64->stderr_handle;
488 		efi_systab.stderr = systab64->stderr;
489 		tmp |= systab64->stderr;
490 		efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
491 		tmp |= systab64->runtime;
492 		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
493 		tmp |= systab64->boottime;
494 		efi_systab.nr_tables = systab64->nr_tables;
495 		efi_systab.tables = systab64->tables;
496 		tmp |= systab64->tables;
497 
498 		early_iounmap(systab64, sizeof(*systab64));
499 #ifdef CONFIG_X86_32
500 		if (tmp >> 32) {
501 			pr_err("EFI data located above 4GB, disabling EFI.\n");
502 			return -EINVAL;
503 		}
504 #endif
505 	} else {
506 		efi_system_table_32_t *systab32;
507 
508 		systab32 = early_ioremap((unsigned long)phys,
509 					 sizeof(*systab32));
510 		if (systab32 == NULL) {
511 			pr_err("Couldn't map the system table!\n");
512 			return -ENOMEM;
513 		}
514 
515 		efi_systab.hdr = systab32->hdr;
516 		efi_systab.fw_vendor = systab32->fw_vendor;
517 		efi_systab.fw_revision = systab32->fw_revision;
518 		efi_systab.con_in_handle = systab32->con_in_handle;
519 		efi_systab.con_in = systab32->con_in;
520 		efi_systab.con_out_handle = systab32->con_out_handle;
521 		efi_systab.con_out = systab32->con_out;
522 		efi_systab.stderr_handle = systab32->stderr_handle;
523 		efi_systab.stderr = systab32->stderr;
524 		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
525 		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
526 		efi_systab.nr_tables = systab32->nr_tables;
527 		efi_systab.tables = systab32->tables;
528 
529 		early_iounmap(systab32, sizeof(*systab32));
530 	}
531 
532 	efi.systab = &efi_systab;
533 
534 	/*
535 	 * Verify the EFI Table
536 	 */
537 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
538 		pr_err("System table signature incorrect!\n");
539 		return -EINVAL;
540 	}
541 	if ((efi.systab->hdr.revision >> 16) == 0)
542 		pr_err("Warning: System table version "
543 		       "%d.%02d, expected 1.00 or greater!\n",
544 		       efi.systab->hdr.revision >> 16,
545 		       efi.systab->hdr.revision & 0xffff);
546 
547 	return 0;
548 }
549 
550 static int __init efi_config_init(u64 tables, int nr_tables)
551 {
552 	void *config_tables, *tablep;
553 	int i, sz;
554 
555 	if (efi_64bit)
556 		sz = sizeof(efi_config_table_64_t);
557 	else
558 		sz = sizeof(efi_config_table_32_t);
559 
560 	/*
561 	 * Let's see what config tables the firmware passed to us.
562 	 */
563 	config_tables = early_ioremap(tables, nr_tables * sz);
564 	if (config_tables == NULL) {
565 		pr_err("Could not map Configuration table!\n");
566 		return -ENOMEM;
567 	}
568 
569 	tablep = config_tables;
570 	pr_info("");
571 	for (i = 0; i < efi.systab->nr_tables; i++) {
572 		efi_guid_t guid;
573 		unsigned long table;
574 
575 		if (efi_64bit) {
576 			u64 table64;
577 			guid = ((efi_config_table_64_t *)tablep)->guid;
578 			table64 = ((efi_config_table_64_t *)tablep)->table;
579 			table = table64;
580 #ifdef CONFIG_X86_32
581 			if (table64 >> 32) {
582 				pr_cont("\n");
583 				pr_err("Table located above 4GB, disabling EFI.\n");
584 				early_iounmap(config_tables,
585 					      efi.systab->nr_tables * sz);
586 				return -EINVAL;
587 			}
588 #endif
589 		} else {
590 			guid = ((efi_config_table_32_t *)tablep)->guid;
591 			table = ((efi_config_table_32_t *)tablep)->table;
592 		}
593 		if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
594 			efi.mps = table;
595 			pr_cont(" MPS=0x%lx ", table);
596 		} else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
597 			efi.acpi20 = table;
598 			pr_cont(" ACPI 2.0=0x%lx ", table);
599 		} else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
600 			efi.acpi = table;
601 			pr_cont(" ACPI=0x%lx ", table);
602 		} else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
603 			efi.smbios = table;
604 			pr_cont(" SMBIOS=0x%lx ", table);
605 #ifdef CONFIG_X86_UV
606 		} else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
607 			efi.uv_systab = table;
608 			pr_cont(" UVsystab=0x%lx ", table);
609 #endif
610 		} else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
611 			efi.hcdp = table;
612 			pr_cont(" HCDP=0x%lx ", table);
613 		} else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
614 			efi.uga = table;
615 			pr_cont(" UGA=0x%lx ", table);
616 		}
617 		tablep += sz;
618 	}
619 	pr_cont("\n");
620 	early_iounmap(config_tables, efi.systab->nr_tables * sz);
621 	return 0;
622 }
623 
624 static int __init efi_runtime_init(void)
625 {
626 	efi_runtime_services_t *runtime;
627 
628 	/*
629 	 * Check out the runtime services table. We need to map
630 	 * the runtime services table so that we can grab the physical
631 	 * address of several of the EFI runtime functions, needed to
632 	 * set the firmware into virtual mode.
633 	 */
634 	runtime = early_ioremap((unsigned long)efi.systab->runtime,
635 				sizeof(efi_runtime_services_t));
636 	if (!runtime) {
637 		pr_err("Could not map the runtime service table!\n");
638 		return -ENOMEM;
639 	}
640 	/*
641 	 * We will only need *early* access to the following
642 	 * two EFI runtime services before set_virtual_address_map
643 	 * is invoked.
644 	 */
645 	efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
646 	efi_phys.set_virtual_address_map =
647 		(efi_set_virtual_address_map_t *)
648 		runtime->set_virtual_address_map;
649 	/*
650 	 * Make efi_get_time can be called before entering
651 	 * virtual mode.
652 	 */
653 	efi.get_time = phys_efi_get_time;
654 	early_iounmap(runtime, sizeof(efi_runtime_services_t));
655 
656 	return 0;
657 }
658 
659 static int __init efi_memmap_init(void)
660 {
661 	/* Map the EFI memory map */
662 	memmap.map = early_ioremap((unsigned long)memmap.phys_map,
663 				   memmap.nr_map * memmap.desc_size);
664 	if (memmap.map == NULL) {
665 		pr_err("Could not map the memory map!\n");
666 		return -ENOMEM;
667 	}
668 	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
669 
670 	if (add_efi_memmap)
671 		do_add_efi_memmap();
672 
673 	return 0;
674 }
675 
676 void __init efi_init(void)
677 {
678 	efi_char16_t *c16;
679 	char vendor[100] = "unknown";
680 	int i = 0;
681 	void *tmp;
682 
683 #ifdef CONFIG_X86_32
684 	if (boot_params.efi_info.efi_systab_hi ||
685 	    boot_params.efi_info.efi_memmap_hi) {
686 		pr_info("Table located above 4GB, disabling EFI.\n");
687 		efi_enabled = 0;
688 		return;
689 	}
690 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
691 #else
692 	efi_phys.systab = (efi_system_table_t *)
693 			  (boot_params.efi_info.efi_systab |
694 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
695 #endif
696 
697 	if (efi_systab_init(efi_phys.systab)) {
698 		efi_enabled = 0;
699 		return;
700 	}
701 
702 	/*
703 	 * Show what we know for posterity
704 	 */
705 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
706 	if (c16) {
707 		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
708 			vendor[i] = *c16++;
709 		vendor[i] = '\0';
710 	} else
711 		pr_err("Could not map the firmware vendor!\n");
712 	early_iounmap(tmp, 2);
713 
714 	pr_info("EFI v%u.%.02u by %s\n",
715 		efi.systab->hdr.revision >> 16,
716 		efi.systab->hdr.revision & 0xffff, vendor);
717 
718 	if (efi_config_init(efi.systab->tables, efi.systab->nr_tables)) {
719 		efi_enabled = 0;
720 		return;
721 	}
722 
723 	/*
724 	 * Note: We currently don't support runtime services on an EFI
725 	 * that doesn't match the kernel 32/64-bit mode.
726 	 */
727 
728 	if (!efi_is_native())
729 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
730 	else if (efi_runtime_init()) {
731 		efi_enabled = 0;
732 		return;
733 	}
734 
735 	if (efi_memmap_init()) {
736 		efi_enabled = 0;
737 		return;
738 	}
739 #ifdef CONFIG_X86_32
740 	if (efi_is_native()) {
741 		x86_platform.get_wallclock = efi_get_time;
742 		x86_platform.set_wallclock = efi_set_rtc_mmss;
743 	}
744 #endif
745 
746 #if EFI_DEBUG
747 	print_efi_memmap();
748 #endif
749 }
750 
751 void __init efi_late_init(void)
752 {
753 	efi_bgrt_init();
754 }
755 
756 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
757 {
758 	u64 addr, npages;
759 
760 	addr = md->virt_addr;
761 	npages = md->num_pages;
762 
763 	memrange_efi_to_native(&addr, &npages);
764 
765 	if (executable)
766 		set_memory_x(addr, npages);
767 	else
768 		set_memory_nx(addr, npages);
769 }
770 
771 static void __init runtime_code_page_mkexec(void)
772 {
773 	efi_memory_desc_t *md;
774 	void *p;
775 
776 	/* Make EFI runtime service code area executable */
777 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
778 		md = p;
779 
780 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
781 			continue;
782 
783 		efi_set_executable(md, true);
784 	}
785 }
786 
787 /*
788  * We can't ioremap data in EFI boot services RAM, because we've already mapped
789  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
790  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
791  */
792 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
793 {
794 	void *p;
795 	if (WARN_ON(!memmap.map))
796 		return NULL;
797 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
798 		efi_memory_desc_t *md = p;
799 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
800 		u64 end = md->phys_addr + size;
801 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
802 		    md->type != EFI_BOOT_SERVICES_CODE &&
803 		    md->type != EFI_BOOT_SERVICES_DATA)
804 			continue;
805 		if (!md->virt_addr)
806 			continue;
807 		if (phys_addr >= md->phys_addr && phys_addr < end) {
808 			phys_addr += md->virt_addr - md->phys_addr;
809 			return (__force void __iomem *)(unsigned long)phys_addr;
810 		}
811 	}
812 	return NULL;
813 }
814 
815 void efi_memory_uc(u64 addr, unsigned long size)
816 {
817 	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
818 	u64 npages;
819 
820 	npages = round_up(size, page_shift) / page_shift;
821 	memrange_efi_to_native(&addr, &npages);
822 	set_memory_uc(addr, npages);
823 }
824 
825 /*
826  * This function will switch the EFI runtime services to virtual mode.
827  * Essentially, look through the EFI memmap and map every region that
828  * has the runtime attribute bit set in its memory descriptor and update
829  * that memory descriptor with the virtual address obtained from ioremap().
830  * This enables the runtime services to be called without having to
831  * thunk back into physical mode for every invocation.
832  */
833 void __init efi_enter_virtual_mode(void)
834 {
835 	efi_memory_desc_t *md, *prev_md = NULL;
836 	efi_status_t status;
837 	unsigned long size;
838 	u64 end, systab, end_pfn;
839 	void *p, *va, *new_memmap = NULL;
840 	int count = 0;
841 
842 	efi.systab = NULL;
843 
844 	/*
845 	 * We don't do virtual mode, since we don't do runtime services, on
846 	 * non-native EFI
847 	 */
848 
849 	if (!efi_is_native()) {
850 		efi_unmap_memmap();
851 		return;
852 	}
853 
854 	/* Merge contiguous regions of the same type and attribute */
855 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
856 		u64 prev_size;
857 		md = p;
858 
859 		if (!prev_md) {
860 			prev_md = md;
861 			continue;
862 		}
863 
864 		if (prev_md->type != md->type ||
865 		    prev_md->attribute != md->attribute) {
866 			prev_md = md;
867 			continue;
868 		}
869 
870 		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
871 
872 		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
873 			prev_md->num_pages += md->num_pages;
874 			md->type = EFI_RESERVED_TYPE;
875 			md->attribute = 0;
876 			continue;
877 		}
878 		prev_md = md;
879 	}
880 
881 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
882 		md = p;
883 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
884 		    md->type != EFI_BOOT_SERVICES_CODE &&
885 		    md->type != EFI_BOOT_SERVICES_DATA)
886 			continue;
887 
888 		size = md->num_pages << EFI_PAGE_SHIFT;
889 		end = md->phys_addr + size;
890 
891 		end_pfn = PFN_UP(end);
892 		if (end_pfn <= max_low_pfn_mapped
893 		    || (end_pfn > (1UL << (32 - PAGE_SHIFT))
894 			&& end_pfn <= max_pfn_mapped)) {
895 			va = __va(md->phys_addr);
896 
897 			if (!(md->attribute & EFI_MEMORY_WB))
898 				efi_memory_uc((u64)(unsigned long)va, size);
899 		} else
900 			va = efi_ioremap(md->phys_addr, size,
901 					 md->type, md->attribute);
902 
903 		md->virt_addr = (u64) (unsigned long) va;
904 
905 		if (!va) {
906 			pr_err("ioremap of 0x%llX failed!\n",
907 			       (unsigned long long)md->phys_addr);
908 			continue;
909 		}
910 
911 		systab = (u64) (unsigned long) efi_phys.systab;
912 		if (md->phys_addr <= systab && systab < end) {
913 			systab += md->virt_addr - md->phys_addr;
914 			efi.systab = (efi_system_table_t *) (unsigned long) systab;
915 		}
916 		new_memmap = krealloc(new_memmap,
917 				      (count + 1) * memmap.desc_size,
918 				      GFP_KERNEL);
919 		memcpy(new_memmap + (count * memmap.desc_size), md,
920 		       memmap.desc_size);
921 		count++;
922 	}
923 
924 	BUG_ON(!efi.systab);
925 
926 	status = phys_efi_set_virtual_address_map(
927 		memmap.desc_size * count,
928 		memmap.desc_size,
929 		memmap.desc_version,
930 		(efi_memory_desc_t *)__pa(new_memmap));
931 
932 	if (status != EFI_SUCCESS) {
933 		pr_alert("Unable to switch EFI into virtual mode "
934 			 "(status=%lx)!\n", status);
935 		panic("EFI call to SetVirtualAddressMap() failed!");
936 	}
937 
938 	/*
939 	 * Now that EFI is in virtual mode, update the function
940 	 * pointers in the runtime service table to the new virtual addresses.
941 	 *
942 	 * Call EFI services through wrapper functions.
943 	 */
944 	efi.runtime_version = efi_systab.fw_revision;
945 	efi.get_time = virt_efi_get_time;
946 	efi.set_time = virt_efi_set_time;
947 	efi.get_wakeup_time = virt_efi_get_wakeup_time;
948 	efi.set_wakeup_time = virt_efi_set_wakeup_time;
949 	efi.get_variable = virt_efi_get_variable;
950 	efi.get_next_variable = virt_efi_get_next_variable;
951 	efi.set_variable = virt_efi_set_variable;
952 	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
953 	efi.reset_system = virt_efi_reset_system;
954 	efi.set_virtual_address_map = NULL;
955 	efi.query_variable_info = virt_efi_query_variable_info;
956 	efi.update_capsule = virt_efi_update_capsule;
957 	efi.query_capsule_caps = virt_efi_query_capsule_caps;
958 	if (__supported_pte_mask & _PAGE_NX)
959 		runtime_code_page_mkexec();
960 
961 	kfree(new_memmap);
962 }
963 
964 /*
965  * Convenience functions to obtain memory types and attributes
966  */
967 u32 efi_mem_type(unsigned long phys_addr)
968 {
969 	efi_memory_desc_t *md;
970 	void *p;
971 
972 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
973 		md = p;
974 		if ((md->phys_addr <= phys_addr) &&
975 		    (phys_addr < (md->phys_addr +
976 				  (md->num_pages << EFI_PAGE_SHIFT))))
977 			return md->type;
978 	}
979 	return 0;
980 }
981 
982 u64 efi_mem_attributes(unsigned long phys_addr)
983 {
984 	efi_memory_desc_t *md;
985 	void *p;
986 
987 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
988 		md = p;
989 		if ((md->phys_addr <= phys_addr) &&
990 		    (phys_addr < (md->phys_addr +
991 				  (md->num_pages << EFI_PAGE_SHIFT))))
992 			return md->attribute;
993 	}
994 	return 0;
995 }
996