xref: /openbmc/linux/arch/x86/platform/efi/efi.c (revision 97da55fc)
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 struct efi __read_mostly efi = {
55 	.mps        = EFI_INVALID_TABLE_ADDR,
56 	.acpi       = EFI_INVALID_TABLE_ADDR,
57 	.acpi20     = EFI_INVALID_TABLE_ADDR,
58 	.smbios     = EFI_INVALID_TABLE_ADDR,
59 	.sal_systab = EFI_INVALID_TABLE_ADDR,
60 	.boot_info  = EFI_INVALID_TABLE_ADDR,
61 	.hcdp       = EFI_INVALID_TABLE_ADDR,
62 	.uga        = EFI_INVALID_TABLE_ADDR,
63 	.uv_systab  = EFI_INVALID_TABLE_ADDR,
64 };
65 EXPORT_SYMBOL(efi);
66 
67 struct efi_memory_map memmap;
68 
69 static struct efi efi_phys __initdata;
70 static efi_system_table_t efi_systab __initdata;
71 
72 unsigned long x86_efi_facility;
73 
74 /*
75  * Returns 1 if 'facility' is enabled, 0 otherwise.
76  */
77 int efi_enabled(int facility)
78 {
79 	return test_bit(facility, &x86_efi_facility) != 0;
80 }
81 EXPORT_SYMBOL(efi_enabled);
82 
83 static bool __initdata disable_runtime = false;
84 static int __init setup_noefi(char *arg)
85 {
86 	disable_runtime = true;
87 	return 0;
88 }
89 early_param("noefi", setup_noefi);
90 
91 int add_efi_memmap;
92 EXPORT_SYMBOL(add_efi_memmap);
93 
94 static int __init setup_add_efi_memmap(char *arg)
95 {
96 	add_efi_memmap = 1;
97 	return 0;
98 }
99 early_param("add_efi_memmap", setup_add_efi_memmap);
100 
101 
102 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
103 {
104 	unsigned long flags;
105 	efi_status_t status;
106 
107 	spin_lock_irqsave(&rtc_lock, flags);
108 	status = efi_call_virt2(get_time, tm, tc);
109 	spin_unlock_irqrestore(&rtc_lock, flags);
110 	return status;
111 }
112 
113 static efi_status_t virt_efi_set_time(efi_time_t *tm)
114 {
115 	unsigned long flags;
116 	efi_status_t status;
117 
118 	spin_lock_irqsave(&rtc_lock, flags);
119 	status = efi_call_virt1(set_time, tm);
120 	spin_unlock_irqrestore(&rtc_lock, flags);
121 	return status;
122 }
123 
124 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
125 					     efi_bool_t *pending,
126 					     efi_time_t *tm)
127 {
128 	unsigned long flags;
129 	efi_status_t status;
130 
131 	spin_lock_irqsave(&rtc_lock, flags);
132 	status = efi_call_virt3(get_wakeup_time,
133 				enabled, pending, tm);
134 	spin_unlock_irqrestore(&rtc_lock, flags);
135 	return status;
136 }
137 
138 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
139 {
140 	unsigned long flags;
141 	efi_status_t status;
142 
143 	spin_lock_irqsave(&rtc_lock, flags);
144 	status = efi_call_virt2(set_wakeup_time,
145 				enabled, tm);
146 	spin_unlock_irqrestore(&rtc_lock, flags);
147 	return status;
148 }
149 
150 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
151 					  efi_guid_t *vendor,
152 					  u32 *attr,
153 					  unsigned long *data_size,
154 					  void *data)
155 {
156 	return efi_call_virt5(get_variable,
157 			      name, vendor, attr,
158 			      data_size, data);
159 }
160 
161 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
162 					       efi_char16_t *name,
163 					       efi_guid_t *vendor)
164 {
165 	return efi_call_virt3(get_next_variable,
166 			      name_size, name, vendor);
167 }
168 
169 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
170 					  efi_guid_t *vendor,
171 					  u32 attr,
172 					  unsigned long data_size,
173 					  void *data)
174 {
175 	return efi_call_virt5(set_variable,
176 			      name, vendor, attr,
177 			      data_size, data);
178 }
179 
180 static efi_status_t virt_efi_query_variable_info(u32 attr,
181 						 u64 *storage_space,
182 						 u64 *remaining_space,
183 						 u64 *max_variable_size)
184 {
185 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
186 		return EFI_UNSUPPORTED;
187 
188 	return efi_call_virt4(query_variable_info, attr, storage_space,
189 			      remaining_space, max_variable_size);
190 }
191 
192 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
193 {
194 	return efi_call_virt1(get_next_high_mono_count, count);
195 }
196 
197 static void virt_efi_reset_system(int reset_type,
198 				  efi_status_t status,
199 				  unsigned long data_size,
200 				  efi_char16_t *data)
201 {
202 	efi_call_virt4(reset_system, reset_type, status,
203 		       data_size, data);
204 }
205 
206 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
207 					    unsigned long count,
208 					    unsigned long sg_list)
209 {
210 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
211 		return EFI_UNSUPPORTED;
212 
213 	return efi_call_virt3(update_capsule, capsules, count, sg_list);
214 }
215 
216 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
217 						unsigned long count,
218 						u64 *max_size,
219 						int *reset_type)
220 {
221 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
222 		return EFI_UNSUPPORTED;
223 
224 	return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
225 			      reset_type);
226 }
227 
228 static efi_status_t __init phys_efi_set_virtual_address_map(
229 	unsigned long memory_map_size,
230 	unsigned long descriptor_size,
231 	u32 descriptor_version,
232 	efi_memory_desc_t *virtual_map)
233 {
234 	efi_status_t status;
235 
236 	efi_call_phys_prelog();
237 	status = efi_call_phys4(efi_phys.set_virtual_address_map,
238 				memory_map_size, descriptor_size,
239 				descriptor_version, virtual_map);
240 	efi_call_phys_epilog();
241 	return status;
242 }
243 
244 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
245 					     efi_time_cap_t *tc)
246 {
247 	unsigned long flags;
248 	efi_status_t status;
249 
250 	spin_lock_irqsave(&rtc_lock, flags);
251 	efi_call_phys_prelog();
252 	status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
253 				virt_to_phys(tc));
254 	efi_call_phys_epilog();
255 	spin_unlock_irqrestore(&rtc_lock, flags);
256 	return status;
257 }
258 
259 int efi_set_rtc_mmss(unsigned long nowtime)
260 {
261 	int real_seconds, real_minutes;
262 	efi_status_t 	status;
263 	efi_time_t 	eft;
264 	efi_time_cap_t 	cap;
265 
266 	status = efi.get_time(&eft, &cap);
267 	if (status != EFI_SUCCESS) {
268 		pr_err("Oops: efitime: can't read time!\n");
269 		return -1;
270 	}
271 
272 	real_seconds = nowtime % 60;
273 	real_minutes = nowtime / 60;
274 	if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
275 		real_minutes += 30;
276 	real_minutes %= 60;
277 	eft.minute = real_minutes;
278 	eft.second = real_seconds;
279 
280 	status = efi.set_time(&eft);
281 	if (status != EFI_SUCCESS) {
282 		pr_err("Oops: efitime: can't write time!\n");
283 		return -1;
284 	}
285 	return 0;
286 }
287 
288 unsigned long efi_get_time(void)
289 {
290 	efi_status_t status;
291 	efi_time_t eft;
292 	efi_time_cap_t cap;
293 
294 	status = efi.get_time(&eft, &cap);
295 	if (status != EFI_SUCCESS)
296 		pr_err("Oops: efitime: can't read time!\n");
297 
298 	return mktime(eft.year, eft.month, eft.day, eft.hour,
299 		      eft.minute, eft.second);
300 }
301 
302 /*
303  * Tell the kernel about the EFI memory map.  This might include
304  * more than the max 128 entries that can fit in the e820 legacy
305  * (zeropage) memory map.
306  */
307 
308 static void __init do_add_efi_memmap(void)
309 {
310 	void *p;
311 
312 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
313 		efi_memory_desc_t *md = p;
314 		unsigned long long start = md->phys_addr;
315 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
316 		int e820_type;
317 
318 		switch (md->type) {
319 		case EFI_LOADER_CODE:
320 		case EFI_LOADER_DATA:
321 		case EFI_BOOT_SERVICES_CODE:
322 		case EFI_BOOT_SERVICES_DATA:
323 		case EFI_CONVENTIONAL_MEMORY:
324 			if (md->attribute & EFI_MEMORY_WB)
325 				e820_type = E820_RAM;
326 			else
327 				e820_type = E820_RESERVED;
328 			break;
329 		case EFI_ACPI_RECLAIM_MEMORY:
330 			e820_type = E820_ACPI;
331 			break;
332 		case EFI_ACPI_MEMORY_NVS:
333 			e820_type = E820_NVS;
334 			break;
335 		case EFI_UNUSABLE_MEMORY:
336 			e820_type = E820_UNUSABLE;
337 			break;
338 		default:
339 			/*
340 			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
341 			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
342 			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
343 			 */
344 			e820_type = E820_RESERVED;
345 			break;
346 		}
347 		e820_add_region(start, size, e820_type);
348 	}
349 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
350 }
351 
352 int __init efi_memblock_x86_reserve_range(void)
353 {
354 	unsigned long pmap;
355 
356 #ifdef CONFIG_X86_32
357 	/* Can't handle data above 4GB at this time */
358 	if (boot_params.efi_info.efi_memmap_hi) {
359 		pr_err("Memory map is above 4GB, disabling EFI.\n");
360 		return -EINVAL;
361 	}
362 	pmap = boot_params.efi_info.efi_memmap;
363 #else
364 	pmap = (boot_params.efi_info.efi_memmap |
365 		((__u64)boot_params.efi_info.efi_memmap_hi<<32));
366 #endif
367 	memmap.phys_map = (void *)pmap;
368 	memmap.nr_map = boot_params.efi_info.efi_memmap_size /
369 		boot_params.efi_info.efi_memdesc_size;
370 	memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
371 	memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
372 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
373 
374 	return 0;
375 }
376 
377 #if EFI_DEBUG
378 static void __init print_efi_memmap(void)
379 {
380 	efi_memory_desc_t *md;
381 	void *p;
382 	int i;
383 
384 	for (p = memmap.map, i = 0;
385 	     p < memmap.map_end;
386 	     p += memmap.desc_size, i++) {
387 		md = p;
388 		pr_info("mem%02u: type=%u, attr=0x%llx, "
389 			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
390 			i, md->type, md->attribute, md->phys_addr,
391 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
392 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
393 	}
394 }
395 #endif  /*  EFI_DEBUG  */
396 
397 void __init efi_reserve_boot_services(void)
398 {
399 	void *p;
400 
401 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
402 		efi_memory_desc_t *md = p;
403 		u64 start = md->phys_addr;
404 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
405 
406 		if (md->type != EFI_BOOT_SERVICES_CODE &&
407 		    md->type != EFI_BOOT_SERVICES_DATA)
408 			continue;
409 		/* Only reserve where possible:
410 		 * - Not within any already allocated areas
411 		 * - Not over any memory area (really needed, if above?)
412 		 * - Not within any part of the kernel
413 		 * - Not the bios reserved area
414 		*/
415 		if ((start+size >= __pa_symbol(_text)
416 				&& start <= __pa_symbol(_end)) ||
417 			!e820_all_mapped(start, start+size, E820_RAM) ||
418 			memblock_is_region_reserved(start, size)) {
419 			/* Could not reserve, skip it */
420 			md->num_pages = 0;
421 			memblock_dbg("Could not reserve boot range "
422 					"[0x%010llx-0x%010llx]\n",
423 						start, start+size-1);
424 		} else
425 			memblock_reserve(start, size);
426 	}
427 }
428 
429 void __init efi_unmap_memmap(void)
430 {
431 	clear_bit(EFI_MEMMAP, &x86_efi_facility);
432 	if (memmap.map) {
433 		early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
434 		memmap.map = NULL;
435 	}
436 }
437 
438 void __init efi_free_boot_services(void)
439 {
440 	void *p;
441 
442 	if (!efi_is_native())
443 		return;
444 
445 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
446 		efi_memory_desc_t *md = p;
447 		unsigned long long start = md->phys_addr;
448 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
449 
450 		if (md->type != EFI_BOOT_SERVICES_CODE &&
451 		    md->type != EFI_BOOT_SERVICES_DATA)
452 			continue;
453 
454 		/* Could not reserve boot area */
455 		if (!size)
456 			continue;
457 
458 		free_bootmem_late(start, size);
459 	}
460 
461 	efi_unmap_memmap();
462 }
463 
464 static int __init efi_systab_init(void *phys)
465 {
466 	if (efi_enabled(EFI_64BIT)) {
467 		efi_system_table_64_t *systab64;
468 		u64 tmp = 0;
469 
470 		systab64 = early_ioremap((unsigned long)phys,
471 					 sizeof(*systab64));
472 		if (systab64 == NULL) {
473 			pr_err("Couldn't map the system table!\n");
474 			return -ENOMEM;
475 		}
476 
477 		efi_systab.hdr = systab64->hdr;
478 		efi_systab.fw_vendor = systab64->fw_vendor;
479 		tmp |= systab64->fw_vendor;
480 		efi_systab.fw_revision = systab64->fw_revision;
481 		efi_systab.con_in_handle = systab64->con_in_handle;
482 		tmp |= systab64->con_in_handle;
483 		efi_systab.con_in = systab64->con_in;
484 		tmp |= systab64->con_in;
485 		efi_systab.con_out_handle = systab64->con_out_handle;
486 		tmp |= systab64->con_out_handle;
487 		efi_systab.con_out = systab64->con_out;
488 		tmp |= systab64->con_out;
489 		efi_systab.stderr_handle = systab64->stderr_handle;
490 		tmp |= systab64->stderr_handle;
491 		efi_systab.stderr = systab64->stderr;
492 		tmp |= systab64->stderr;
493 		efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
494 		tmp |= systab64->runtime;
495 		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
496 		tmp |= systab64->boottime;
497 		efi_systab.nr_tables = systab64->nr_tables;
498 		efi_systab.tables = systab64->tables;
499 		tmp |= systab64->tables;
500 
501 		early_iounmap(systab64, sizeof(*systab64));
502 #ifdef CONFIG_X86_32
503 		if (tmp >> 32) {
504 			pr_err("EFI data located above 4GB, disabling EFI.\n");
505 			return -EINVAL;
506 		}
507 #endif
508 	} else {
509 		efi_system_table_32_t *systab32;
510 
511 		systab32 = early_ioremap((unsigned long)phys,
512 					 sizeof(*systab32));
513 		if (systab32 == NULL) {
514 			pr_err("Couldn't map the system table!\n");
515 			return -ENOMEM;
516 		}
517 
518 		efi_systab.hdr = systab32->hdr;
519 		efi_systab.fw_vendor = systab32->fw_vendor;
520 		efi_systab.fw_revision = systab32->fw_revision;
521 		efi_systab.con_in_handle = systab32->con_in_handle;
522 		efi_systab.con_in = systab32->con_in;
523 		efi_systab.con_out_handle = systab32->con_out_handle;
524 		efi_systab.con_out = systab32->con_out;
525 		efi_systab.stderr_handle = systab32->stderr_handle;
526 		efi_systab.stderr = systab32->stderr;
527 		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
528 		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
529 		efi_systab.nr_tables = systab32->nr_tables;
530 		efi_systab.tables = systab32->tables;
531 
532 		early_iounmap(systab32, sizeof(*systab32));
533 	}
534 
535 	efi.systab = &efi_systab;
536 
537 	/*
538 	 * Verify the EFI Table
539 	 */
540 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
541 		pr_err("System table signature incorrect!\n");
542 		return -EINVAL;
543 	}
544 	if ((efi.systab->hdr.revision >> 16) == 0)
545 		pr_err("Warning: System table version "
546 		       "%d.%02d, expected 1.00 or greater!\n",
547 		       efi.systab->hdr.revision >> 16,
548 		       efi.systab->hdr.revision & 0xffff);
549 
550 	return 0;
551 }
552 
553 static int __init efi_config_init(u64 tables, int nr_tables)
554 {
555 	void *config_tables, *tablep;
556 	int i, sz;
557 
558 	if (efi_enabled(EFI_64BIT))
559 		sz = sizeof(efi_config_table_64_t);
560 	else
561 		sz = sizeof(efi_config_table_32_t);
562 
563 	/*
564 	 * Let's see what config tables the firmware passed to us.
565 	 */
566 	config_tables = early_ioremap(tables, nr_tables * sz);
567 	if (config_tables == NULL) {
568 		pr_err("Could not map Configuration table!\n");
569 		return -ENOMEM;
570 	}
571 
572 	tablep = config_tables;
573 	pr_info("");
574 	for (i = 0; i < efi.systab->nr_tables; i++) {
575 		efi_guid_t guid;
576 		unsigned long table;
577 
578 		if (efi_enabled(EFI_64BIT)) {
579 			u64 table64;
580 			guid = ((efi_config_table_64_t *)tablep)->guid;
581 			table64 = ((efi_config_table_64_t *)tablep)->table;
582 			table = table64;
583 #ifdef CONFIG_X86_32
584 			if (table64 >> 32) {
585 				pr_cont("\n");
586 				pr_err("Table located above 4GB, disabling EFI.\n");
587 				early_iounmap(config_tables,
588 					      efi.systab->nr_tables * sz);
589 				return -EINVAL;
590 			}
591 #endif
592 		} else {
593 			guid = ((efi_config_table_32_t *)tablep)->guid;
594 			table = ((efi_config_table_32_t *)tablep)->table;
595 		}
596 		if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
597 			efi.mps = table;
598 			pr_cont(" MPS=0x%lx ", table);
599 		} else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
600 			efi.acpi20 = table;
601 			pr_cont(" ACPI 2.0=0x%lx ", table);
602 		} else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
603 			efi.acpi = table;
604 			pr_cont(" ACPI=0x%lx ", table);
605 		} else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
606 			efi.smbios = table;
607 			pr_cont(" SMBIOS=0x%lx ", table);
608 #ifdef CONFIG_X86_UV
609 		} else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
610 			efi.uv_systab = table;
611 			pr_cont(" UVsystab=0x%lx ", table);
612 #endif
613 		} else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
614 			efi.hcdp = table;
615 			pr_cont(" HCDP=0x%lx ", table);
616 		} else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
617 			efi.uga = table;
618 			pr_cont(" UGA=0x%lx ", table);
619 		}
620 		tablep += sz;
621 	}
622 	pr_cont("\n");
623 	early_iounmap(config_tables, efi.systab->nr_tables * sz);
624 	return 0;
625 }
626 
627 static int __init efi_runtime_init(void)
628 {
629 	efi_runtime_services_t *runtime;
630 
631 	/*
632 	 * Check out the runtime services table. We need to map
633 	 * the runtime services table so that we can grab the physical
634 	 * address of several of the EFI runtime functions, needed to
635 	 * set the firmware into virtual mode.
636 	 */
637 	runtime = early_ioremap((unsigned long)efi.systab->runtime,
638 				sizeof(efi_runtime_services_t));
639 	if (!runtime) {
640 		pr_err("Could not map the runtime service table!\n");
641 		return -ENOMEM;
642 	}
643 	/*
644 	 * We will only need *early* access to the following
645 	 * two EFI runtime services before set_virtual_address_map
646 	 * is invoked.
647 	 */
648 	efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
649 	efi_phys.set_virtual_address_map =
650 		(efi_set_virtual_address_map_t *)
651 		runtime->set_virtual_address_map;
652 	/*
653 	 * Make efi_get_time can be called before entering
654 	 * virtual mode.
655 	 */
656 	efi.get_time = phys_efi_get_time;
657 	early_iounmap(runtime, sizeof(efi_runtime_services_t));
658 
659 	return 0;
660 }
661 
662 static int __init efi_memmap_init(void)
663 {
664 	/* Map the EFI memory map */
665 	memmap.map = early_ioremap((unsigned long)memmap.phys_map,
666 				   memmap.nr_map * memmap.desc_size);
667 	if (memmap.map == NULL) {
668 		pr_err("Could not map the memory map!\n");
669 		return -ENOMEM;
670 	}
671 	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
672 
673 	if (add_efi_memmap)
674 		do_add_efi_memmap();
675 
676 	return 0;
677 }
678 
679 void __init efi_init(void)
680 {
681 	efi_char16_t *c16;
682 	char vendor[100] = "unknown";
683 	int i = 0;
684 	void *tmp;
685 
686 #ifdef CONFIG_X86_32
687 	if (boot_params.efi_info.efi_systab_hi ||
688 	    boot_params.efi_info.efi_memmap_hi) {
689 		pr_info("Table located above 4GB, disabling EFI.\n");
690 		return;
691 	}
692 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
693 #else
694 	efi_phys.systab = (efi_system_table_t *)
695 			  (boot_params.efi_info.efi_systab |
696 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
697 #endif
698 
699 	if (efi_systab_init(efi_phys.systab))
700 		return;
701 
702 	set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
703 
704 	/*
705 	 * Show what we know for posterity
706 	 */
707 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
708 	if (c16) {
709 		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
710 			vendor[i] = *c16++;
711 		vendor[i] = '\0';
712 	} else
713 		pr_err("Could not map the firmware vendor!\n");
714 	early_iounmap(tmp, 2);
715 
716 	pr_info("EFI v%u.%.02u by %s\n",
717 		efi.systab->hdr.revision >> 16,
718 		efi.systab->hdr.revision & 0xffff, vendor);
719 
720 	if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
721 		return;
722 
723 	set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
724 
725 	/*
726 	 * Note: We currently don't support runtime services on an EFI
727 	 * that doesn't match the kernel 32/64-bit mode.
728 	 */
729 
730 	if (!efi_is_native())
731 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
732 	else {
733 		if (disable_runtime || efi_runtime_init())
734 			return;
735 		set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
736 	}
737 
738 	if (efi_memmap_init())
739 		return;
740 
741 	set_bit(EFI_MEMMAP, &x86_efi_facility);
742 
743 #ifdef CONFIG_X86_32
744 	if (efi_is_native()) {
745 		x86_platform.get_wallclock = efi_get_time;
746 		x86_platform.set_wallclock = efi_set_rtc_mmss;
747 	}
748 #endif
749 
750 #if EFI_DEBUG
751 	print_efi_memmap();
752 #endif
753 }
754 
755 void __init efi_late_init(void)
756 {
757 	efi_bgrt_init();
758 }
759 
760 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
761 {
762 	u64 addr, npages;
763 
764 	addr = md->virt_addr;
765 	npages = md->num_pages;
766 
767 	memrange_efi_to_native(&addr, &npages);
768 
769 	if (executable)
770 		set_memory_x(addr, npages);
771 	else
772 		set_memory_nx(addr, npages);
773 }
774 
775 static void __init runtime_code_page_mkexec(void)
776 {
777 	efi_memory_desc_t *md;
778 	void *p;
779 
780 	/* Make EFI runtime service code area executable */
781 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
782 		md = p;
783 
784 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
785 			continue;
786 
787 		efi_set_executable(md, true);
788 	}
789 }
790 
791 /*
792  * We can't ioremap data in EFI boot services RAM, because we've already mapped
793  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
794  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
795  */
796 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
797 {
798 	void *p;
799 	if (WARN_ON(!memmap.map))
800 		return NULL;
801 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
802 		efi_memory_desc_t *md = p;
803 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
804 		u64 end = md->phys_addr + size;
805 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
806 		    md->type != EFI_BOOT_SERVICES_CODE &&
807 		    md->type != EFI_BOOT_SERVICES_DATA)
808 			continue;
809 		if (!md->virt_addr)
810 			continue;
811 		if (phys_addr >= md->phys_addr && phys_addr < end) {
812 			phys_addr += md->virt_addr - md->phys_addr;
813 			return (__force void __iomem *)(unsigned long)phys_addr;
814 		}
815 	}
816 	return NULL;
817 }
818 
819 void efi_memory_uc(u64 addr, unsigned long size)
820 {
821 	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
822 	u64 npages;
823 
824 	npages = round_up(size, page_shift) / page_shift;
825 	memrange_efi_to_native(&addr, &npages);
826 	set_memory_uc(addr, npages);
827 }
828 
829 /*
830  * This function will switch the EFI runtime services to virtual mode.
831  * Essentially, look through the EFI memmap and map every region that
832  * has the runtime attribute bit set in its memory descriptor and update
833  * that memory descriptor with the virtual address obtained from ioremap().
834  * This enables the runtime services to be called without having to
835  * thunk back into physical mode for every invocation.
836  */
837 void __init efi_enter_virtual_mode(void)
838 {
839 	efi_memory_desc_t *md, *prev_md = NULL;
840 	efi_status_t status;
841 	unsigned long size;
842 	u64 end, systab, start_pfn, end_pfn;
843 	void *p, *va, *new_memmap = NULL;
844 	int count = 0;
845 
846 	efi.systab = NULL;
847 
848 	/*
849 	 * We don't do virtual mode, since we don't do runtime services, on
850 	 * non-native EFI
851 	 */
852 
853 	if (!efi_is_native()) {
854 		efi_unmap_memmap();
855 		return;
856 	}
857 
858 	/* Merge contiguous regions of the same type and attribute */
859 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
860 		u64 prev_size;
861 		md = p;
862 
863 		if (!prev_md) {
864 			prev_md = md;
865 			continue;
866 		}
867 
868 		if (prev_md->type != md->type ||
869 		    prev_md->attribute != md->attribute) {
870 			prev_md = md;
871 			continue;
872 		}
873 
874 		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
875 
876 		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
877 			prev_md->num_pages += md->num_pages;
878 			md->type = EFI_RESERVED_TYPE;
879 			md->attribute = 0;
880 			continue;
881 		}
882 		prev_md = md;
883 	}
884 
885 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
886 		md = p;
887 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
888 		    md->type != EFI_BOOT_SERVICES_CODE &&
889 		    md->type != EFI_BOOT_SERVICES_DATA)
890 			continue;
891 
892 		size = md->num_pages << EFI_PAGE_SHIFT;
893 		end = md->phys_addr + size;
894 
895 		start_pfn = PFN_DOWN(md->phys_addr);
896 		end_pfn = PFN_UP(end);
897 		if (pfn_range_is_mapped(start_pfn, end_pfn)) {
898 			va = __va(md->phys_addr);
899 
900 			if (!(md->attribute & EFI_MEMORY_WB))
901 				efi_memory_uc((u64)(unsigned long)va, size);
902 		} else
903 			va = efi_ioremap(md->phys_addr, size,
904 					 md->type, md->attribute);
905 
906 		md->virt_addr = (u64) (unsigned long) va;
907 
908 		if (!va) {
909 			pr_err("ioremap of 0x%llX failed!\n",
910 			       (unsigned long long)md->phys_addr);
911 			continue;
912 		}
913 
914 		systab = (u64) (unsigned long) efi_phys.systab;
915 		if (md->phys_addr <= systab && systab < end) {
916 			systab += md->virt_addr - md->phys_addr;
917 			efi.systab = (efi_system_table_t *) (unsigned long) systab;
918 		}
919 		new_memmap = krealloc(new_memmap,
920 				      (count + 1) * memmap.desc_size,
921 				      GFP_KERNEL);
922 		memcpy(new_memmap + (count * memmap.desc_size), md,
923 		       memmap.desc_size);
924 		count++;
925 	}
926 
927 	BUG_ON(!efi.systab);
928 
929 	status = phys_efi_set_virtual_address_map(
930 		memmap.desc_size * count,
931 		memmap.desc_size,
932 		memmap.desc_version,
933 		(efi_memory_desc_t *)__pa(new_memmap));
934 
935 	if (status != EFI_SUCCESS) {
936 		pr_alert("Unable to switch EFI into virtual mode "
937 			 "(status=%lx)!\n", status);
938 		panic("EFI call to SetVirtualAddressMap() failed!");
939 	}
940 
941 	/*
942 	 * Now that EFI is in virtual mode, update the function
943 	 * pointers in the runtime service table to the new virtual addresses.
944 	 *
945 	 * Call EFI services through wrapper functions.
946 	 */
947 	efi.runtime_version = efi_systab.hdr.revision;
948 	efi.get_time = virt_efi_get_time;
949 	efi.set_time = virt_efi_set_time;
950 	efi.get_wakeup_time = virt_efi_get_wakeup_time;
951 	efi.set_wakeup_time = virt_efi_set_wakeup_time;
952 	efi.get_variable = virt_efi_get_variable;
953 	efi.get_next_variable = virt_efi_get_next_variable;
954 	efi.set_variable = virt_efi_set_variable;
955 	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
956 	efi.reset_system = virt_efi_reset_system;
957 	efi.set_virtual_address_map = NULL;
958 	efi.query_variable_info = virt_efi_query_variable_info;
959 	efi.update_capsule = virt_efi_update_capsule;
960 	efi.query_capsule_caps = virt_efi_query_capsule_caps;
961 	if (__supported_pte_mask & _PAGE_NX)
962 		runtime_code_page_mkexec();
963 
964 	kfree(new_memmap);
965 }
966 
967 /*
968  * Convenience functions to obtain memory types and attributes
969  */
970 u32 efi_mem_type(unsigned long phys_addr)
971 {
972 	efi_memory_desc_t *md;
973 	void *p;
974 
975 	if (!efi_enabled(EFI_MEMMAP))
976 		return 0;
977 
978 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
979 		md = p;
980 		if ((md->phys_addr <= phys_addr) &&
981 		    (phys_addr < (md->phys_addr +
982 				  (md->num_pages << EFI_PAGE_SHIFT))))
983 			return md->type;
984 	}
985 	return 0;
986 }
987 
988 u64 efi_mem_attributes(unsigned long phys_addr)
989 {
990 	efi_memory_desc_t *md;
991 	void *p;
992 
993 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
994 		md = p;
995 		if ((md->phys_addr <= phys_addr) &&
996 		    (phys_addr < (md->phys_addr +
997 				  (md->num_pages << EFI_PAGE_SHIFT))))
998 			return md->attribute;
999 	}
1000 	return 0;
1001 }
1002