xref: /linux/arch/x86/platform/efi/efi.c (revision 25aee3debe0464f6c680173041fa3de30ec9ff54)
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/export.h>
35 #include <linux/bootmem.h>
36 #include <linux/memblock.h>
37 #include <linux/spinlock.h>
38 #include <linux/uaccess.h>
39 #include <linux/time.h>
40 #include <linux/io.h>
41 #include <linux/reboot.h>
42 #include <linux/bcd.h>
43 
44 #include <asm/setup.h>
45 #include <asm/efi.h>
46 #include <asm/time.h>
47 #include <asm/cacheflush.h>
48 #include <asm/tlbflush.h>
49 #include <asm/x86_init.h>
50 
51 #define EFI_DEBUG	1
52 
53 int efi_enabled;
54 EXPORT_SYMBOL(efi_enabled);
55 
56 struct efi __read_mostly efi = {
57 	.mps        = EFI_INVALID_TABLE_ADDR,
58 	.acpi       = EFI_INVALID_TABLE_ADDR,
59 	.acpi20     = EFI_INVALID_TABLE_ADDR,
60 	.smbios     = EFI_INVALID_TABLE_ADDR,
61 	.sal_systab = EFI_INVALID_TABLE_ADDR,
62 	.boot_info  = EFI_INVALID_TABLE_ADDR,
63 	.hcdp       = EFI_INVALID_TABLE_ADDR,
64 	.uga        = EFI_INVALID_TABLE_ADDR,
65 	.uv_systab  = EFI_INVALID_TABLE_ADDR,
66 };
67 EXPORT_SYMBOL(efi);
68 
69 struct efi_memory_map memmap;
70 
71 bool efi_64bit;
72 static bool efi_native;
73 
74 static struct efi efi_phys __initdata;
75 static efi_system_table_t efi_systab __initdata;
76 
77 static int __init setup_noefi(char *arg)
78 {
79 	efi_enabled = 0;
80 	return 0;
81 }
82 early_param("noefi", setup_noefi);
83 
84 int add_efi_memmap;
85 EXPORT_SYMBOL(add_efi_memmap);
86 
87 static int __init setup_add_efi_memmap(char *arg)
88 {
89 	add_efi_memmap = 1;
90 	return 0;
91 }
92 early_param("add_efi_memmap", setup_add_efi_memmap);
93 
94 
95 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
96 {
97 	unsigned long flags;
98 	efi_status_t status;
99 
100 	spin_lock_irqsave(&rtc_lock, flags);
101 	status = efi_call_virt2(get_time, tm, tc);
102 	spin_unlock_irqrestore(&rtc_lock, flags);
103 	return status;
104 }
105 
106 static efi_status_t virt_efi_set_time(efi_time_t *tm)
107 {
108 	unsigned long flags;
109 	efi_status_t status;
110 
111 	spin_lock_irqsave(&rtc_lock, flags);
112 	status = efi_call_virt1(set_time, tm);
113 	spin_unlock_irqrestore(&rtc_lock, flags);
114 	return status;
115 }
116 
117 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
118 					     efi_bool_t *pending,
119 					     efi_time_t *tm)
120 {
121 	unsigned long flags;
122 	efi_status_t status;
123 
124 	spin_lock_irqsave(&rtc_lock, flags);
125 	status = efi_call_virt3(get_wakeup_time,
126 				enabled, pending, tm);
127 	spin_unlock_irqrestore(&rtc_lock, flags);
128 	return status;
129 }
130 
131 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
132 {
133 	unsigned long flags;
134 	efi_status_t status;
135 
136 	spin_lock_irqsave(&rtc_lock, flags);
137 	status = efi_call_virt2(set_wakeup_time,
138 				enabled, tm);
139 	spin_unlock_irqrestore(&rtc_lock, flags);
140 	return status;
141 }
142 
143 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
144 					  efi_guid_t *vendor,
145 					  u32 *attr,
146 					  unsigned long *data_size,
147 					  void *data)
148 {
149 	return efi_call_virt5(get_variable,
150 			      name, vendor, attr,
151 			      data_size, data);
152 }
153 
154 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
155 					       efi_char16_t *name,
156 					       efi_guid_t *vendor)
157 {
158 	return efi_call_virt3(get_next_variable,
159 			      name_size, name, vendor);
160 }
161 
162 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
163 					  efi_guid_t *vendor,
164 					  u32 attr,
165 					  unsigned long data_size,
166 					  void *data)
167 {
168 	return efi_call_virt5(set_variable,
169 			      name, vendor, attr,
170 			      data_size, data);
171 }
172 
173 static efi_status_t virt_efi_query_variable_info(u32 attr,
174 						 u64 *storage_space,
175 						 u64 *remaining_space,
176 						 u64 *max_variable_size)
177 {
178 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
179 		return EFI_UNSUPPORTED;
180 
181 	return efi_call_virt4(query_variable_info, attr, storage_space,
182 			      remaining_space, max_variable_size);
183 }
184 
185 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
186 {
187 	return efi_call_virt1(get_next_high_mono_count, count);
188 }
189 
190 static void virt_efi_reset_system(int reset_type,
191 				  efi_status_t status,
192 				  unsigned long data_size,
193 				  efi_char16_t *data)
194 {
195 	efi_call_virt4(reset_system, reset_type, status,
196 		       data_size, data);
197 }
198 
199 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
200 					    unsigned long count,
201 					    unsigned long sg_list)
202 {
203 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
204 		return EFI_UNSUPPORTED;
205 
206 	return efi_call_virt3(update_capsule, capsules, count, sg_list);
207 }
208 
209 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
210 						unsigned long count,
211 						u64 *max_size,
212 						int *reset_type)
213 {
214 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
215 		return EFI_UNSUPPORTED;
216 
217 	return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
218 			      reset_type);
219 }
220 
221 static efi_status_t __init phys_efi_set_virtual_address_map(
222 	unsigned long memory_map_size,
223 	unsigned long descriptor_size,
224 	u32 descriptor_version,
225 	efi_memory_desc_t *virtual_map)
226 {
227 	efi_status_t status;
228 
229 	efi_call_phys_prelog();
230 	status = efi_call_phys4(efi_phys.set_virtual_address_map,
231 				memory_map_size, descriptor_size,
232 				descriptor_version, virtual_map);
233 	efi_call_phys_epilog();
234 	return status;
235 }
236 
237 static int efi_set_rtc_mmss(unsigned long nowtime)
238 {
239 	int real_seconds, real_minutes;
240 	efi_status_t 	status;
241 	efi_time_t 	eft;
242 	efi_time_cap_t 	cap;
243 
244 	status = efi.get_time(&eft, &cap);
245 	if (status != EFI_SUCCESS) {
246 		pr_err("Oops: efitime: can't read time!\n");
247 		return -1;
248 	}
249 
250 	real_seconds = nowtime % 60;
251 	real_minutes = nowtime / 60;
252 	if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
253 		real_minutes += 30;
254 	real_minutes %= 60;
255 	eft.minute = real_minutes;
256 	eft.second = real_seconds;
257 
258 	status = efi.set_time(&eft);
259 	if (status != EFI_SUCCESS) {
260 		pr_err("Oops: efitime: can't write time!\n");
261 		return -1;
262 	}
263 	return 0;
264 }
265 
266 static unsigned long efi_get_time(void)
267 {
268 	efi_status_t status;
269 	efi_time_t eft;
270 	efi_time_cap_t cap;
271 
272 	status = efi.get_time(&eft, &cap);
273 	if (status != EFI_SUCCESS)
274 		pr_err("Oops: efitime: can't read time!\n");
275 
276 	return mktime(eft.year, eft.month, eft.day, eft.hour,
277 		      eft.minute, eft.second);
278 }
279 
280 /*
281  * Tell the kernel about the EFI memory map.  This might include
282  * more than the max 128 entries that can fit in the e820 legacy
283  * (zeropage) memory map.
284  */
285 
286 static void __init do_add_efi_memmap(void)
287 {
288 	void *p;
289 
290 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
291 		efi_memory_desc_t *md = p;
292 		unsigned long long start = md->phys_addr;
293 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
294 		int e820_type;
295 
296 		switch (md->type) {
297 		case EFI_LOADER_CODE:
298 		case EFI_LOADER_DATA:
299 		case EFI_BOOT_SERVICES_CODE:
300 		case EFI_BOOT_SERVICES_DATA:
301 		case EFI_CONVENTIONAL_MEMORY:
302 			if (md->attribute & EFI_MEMORY_WB)
303 				e820_type = E820_RAM;
304 			else
305 				e820_type = E820_RESERVED;
306 			break;
307 		case EFI_ACPI_RECLAIM_MEMORY:
308 			e820_type = E820_ACPI;
309 			break;
310 		case EFI_ACPI_MEMORY_NVS:
311 			e820_type = E820_NVS;
312 			break;
313 		case EFI_UNUSABLE_MEMORY:
314 			e820_type = E820_UNUSABLE;
315 			break;
316 		default:
317 			/*
318 			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
319 			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
320 			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
321 			 */
322 			e820_type = E820_RESERVED;
323 			break;
324 		}
325 		e820_add_region(start, size, e820_type);
326 	}
327 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
328 }
329 
330 int __init efi_memblock_x86_reserve_range(void)
331 {
332 	unsigned long pmap;
333 
334 #ifdef CONFIG_X86_32
335 	/* Can't handle data above 4GB at this time */
336 	if (boot_params.efi_info.efi_memmap_hi) {
337 		pr_err("Memory map is above 4GB, disabling EFI.\n");
338 		return -EINVAL;
339 	}
340 	pmap = boot_params.efi_info.efi_memmap;
341 #else
342 	pmap = (boot_params.efi_info.efi_memmap |
343 		((__u64)boot_params.efi_info.efi_memmap_hi<<32));
344 #endif
345 	memmap.phys_map = (void *)pmap;
346 	memmap.nr_map = boot_params.efi_info.efi_memmap_size /
347 		boot_params.efi_info.efi_memdesc_size;
348 	memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
349 	memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
350 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
351 
352 	return 0;
353 }
354 
355 #if EFI_DEBUG
356 static void __init print_efi_memmap(void)
357 {
358 	efi_memory_desc_t *md;
359 	void *p;
360 	int i;
361 
362 	for (p = memmap.map, i = 0;
363 	     p < memmap.map_end;
364 	     p += memmap.desc_size, i++) {
365 		md = p;
366 		pr_info("mem%02u: type=%u, attr=0x%llx, "
367 			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
368 			i, md->type, md->attribute, md->phys_addr,
369 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
370 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
371 	}
372 }
373 #endif  /*  EFI_DEBUG  */
374 
375 void __init efi_reserve_boot_services(void)
376 {
377 	void *p;
378 
379 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
380 		efi_memory_desc_t *md = p;
381 		u64 start = md->phys_addr;
382 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
383 
384 		if (md->type != EFI_BOOT_SERVICES_CODE &&
385 		    md->type != EFI_BOOT_SERVICES_DATA)
386 			continue;
387 		/* Only reserve where possible:
388 		 * - Not within any already allocated areas
389 		 * - Not over any memory area (really needed, if above?)
390 		 * - Not within any part of the kernel
391 		 * - Not the bios reserved area
392 		*/
393 		if ((start+size >= virt_to_phys(_text)
394 				&& start <= virt_to_phys(_end)) ||
395 			!e820_all_mapped(start, start+size, E820_RAM) ||
396 			memblock_is_region_reserved(start, size)) {
397 			/* Could not reserve, skip it */
398 			md->num_pages = 0;
399 			memblock_dbg("Could not reserve boot range "
400 					"[0x%010llx-0x%010llx]\n",
401 						start, start+size-1);
402 		} else
403 			memblock_reserve(start, size);
404 	}
405 }
406 
407 static void __init efi_free_boot_services(void)
408 {
409 	void *p;
410 
411 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
412 		efi_memory_desc_t *md = p;
413 		unsigned long long start = md->phys_addr;
414 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
415 
416 		if (md->type != EFI_BOOT_SERVICES_CODE &&
417 		    md->type != EFI_BOOT_SERVICES_DATA)
418 			continue;
419 
420 		/* Could not reserve boot area */
421 		if (!size)
422 			continue;
423 
424 		free_bootmem_late(start, size);
425 	}
426 }
427 
428 static int __init efi_systab_init(void *phys)
429 {
430 	if (efi_64bit) {
431 		efi_system_table_64_t *systab64;
432 		u64 tmp = 0;
433 
434 		systab64 = early_ioremap((unsigned long)phys,
435 					 sizeof(*systab64));
436 		if (systab64 == NULL) {
437 			pr_err("Couldn't map the system table!\n");
438 			return -ENOMEM;
439 		}
440 
441 		efi_systab.hdr = systab64->hdr;
442 		efi_systab.fw_vendor = systab64->fw_vendor;
443 		tmp |= systab64->fw_vendor;
444 		efi_systab.fw_revision = systab64->fw_revision;
445 		efi_systab.con_in_handle = systab64->con_in_handle;
446 		tmp |= systab64->con_in_handle;
447 		efi_systab.con_in = systab64->con_in;
448 		tmp |= systab64->con_in;
449 		efi_systab.con_out_handle = systab64->con_out_handle;
450 		tmp |= systab64->con_out_handle;
451 		efi_systab.con_out = systab64->con_out;
452 		tmp |= systab64->con_out;
453 		efi_systab.stderr_handle = systab64->stderr_handle;
454 		tmp |= systab64->stderr_handle;
455 		efi_systab.stderr = systab64->stderr;
456 		tmp |= systab64->stderr;
457 		efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
458 		tmp |= systab64->runtime;
459 		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
460 		tmp |= systab64->boottime;
461 		efi_systab.nr_tables = systab64->nr_tables;
462 		efi_systab.tables = systab64->tables;
463 		tmp |= systab64->tables;
464 
465 		early_iounmap(systab64, sizeof(*systab64));
466 #ifdef CONFIG_X86_32
467 		if (tmp >> 32) {
468 			pr_err("EFI data located above 4GB, disabling EFI.\n");
469 			return -EINVAL;
470 		}
471 #endif
472 	} else {
473 		efi_system_table_32_t *systab32;
474 
475 		systab32 = early_ioremap((unsigned long)phys,
476 					 sizeof(*systab32));
477 		if (systab32 == NULL) {
478 			pr_err("Couldn't map the system table!\n");
479 			return -ENOMEM;
480 		}
481 
482 		efi_systab.hdr = systab32->hdr;
483 		efi_systab.fw_vendor = systab32->fw_vendor;
484 		efi_systab.fw_revision = systab32->fw_revision;
485 		efi_systab.con_in_handle = systab32->con_in_handle;
486 		efi_systab.con_in = systab32->con_in;
487 		efi_systab.con_out_handle = systab32->con_out_handle;
488 		efi_systab.con_out = systab32->con_out;
489 		efi_systab.stderr_handle = systab32->stderr_handle;
490 		efi_systab.stderr = systab32->stderr;
491 		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
492 		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
493 		efi_systab.nr_tables = systab32->nr_tables;
494 		efi_systab.tables = systab32->tables;
495 
496 		early_iounmap(systab32, sizeof(*systab32));
497 	}
498 
499 	efi.systab = &efi_systab;
500 
501 	/*
502 	 * Verify the EFI Table
503 	 */
504 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
505 		pr_err("System table signature incorrect!\n");
506 		return -EINVAL;
507 	}
508 	if ((efi.systab->hdr.revision >> 16) == 0)
509 		pr_err("Warning: System table version "
510 		       "%d.%02d, expected 1.00 or greater!\n",
511 		       efi.systab->hdr.revision >> 16,
512 		       efi.systab->hdr.revision & 0xffff);
513 
514 	return 0;
515 }
516 
517 static int __init efi_config_init(u64 tables, int nr_tables)
518 {
519 	void *config_tables, *tablep;
520 	int i, sz;
521 
522 	if (efi_64bit)
523 		sz = sizeof(efi_config_table_64_t);
524 	else
525 		sz = sizeof(efi_config_table_32_t);
526 
527 	/*
528 	 * Let's see what config tables the firmware passed to us.
529 	 */
530 	config_tables = early_ioremap(tables, nr_tables * sz);
531 	if (config_tables == NULL) {
532 		pr_err("Could not map Configuration table!\n");
533 		return -ENOMEM;
534 	}
535 
536 	tablep = config_tables;
537 	pr_info("");
538 	for (i = 0; i < efi.systab->nr_tables; i++) {
539 		efi_guid_t guid;
540 		unsigned long table;
541 
542 		if (efi_64bit) {
543 			u64 table64;
544 			guid = ((efi_config_table_64_t *)tablep)->guid;
545 			table64 = ((efi_config_table_64_t *)tablep)->table;
546 			table = table64;
547 #ifdef CONFIG_X86_32
548 			if (table64 >> 32) {
549 				pr_cont("\n");
550 				pr_err("Table located above 4GB, disabling EFI.\n");
551 				early_iounmap(config_tables,
552 					      efi.systab->nr_tables * sz);
553 				return -EINVAL;
554 			}
555 #endif
556 		} else {
557 			guid = ((efi_config_table_32_t *)tablep)->guid;
558 			table = ((efi_config_table_32_t *)tablep)->table;
559 		}
560 		if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
561 			efi.mps = table;
562 			pr_cont(" MPS=0x%lx ", table);
563 		} else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
564 			efi.acpi20 = table;
565 			pr_cont(" ACPI 2.0=0x%lx ", table);
566 		} else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
567 			efi.acpi = table;
568 			pr_cont(" ACPI=0x%lx ", table);
569 		} else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
570 			efi.smbios = table;
571 			pr_cont(" SMBIOS=0x%lx ", table);
572 #ifdef CONFIG_X86_UV
573 		} else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
574 			efi.uv_systab = table;
575 			pr_cont(" UVsystab=0x%lx ", table);
576 #endif
577 		} else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
578 			efi.hcdp = table;
579 			pr_cont(" HCDP=0x%lx ", table);
580 		} else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
581 			efi.uga = table;
582 			pr_cont(" UGA=0x%lx ", table);
583 		}
584 		tablep += sz;
585 	}
586 	pr_cont("\n");
587 	early_iounmap(config_tables, efi.systab->nr_tables * sz);
588 	return 0;
589 }
590 
591 static int __init efi_runtime_init(void)
592 {
593 	efi_runtime_services_t *runtime;
594 
595 	/*
596 	 * Check out the runtime services table. We need to map
597 	 * the runtime services table so that we can grab the physical
598 	 * address of several of the EFI runtime functions, needed to
599 	 * set the firmware into virtual mode.
600 	 */
601 	runtime = early_ioremap((unsigned long)efi.systab->runtime,
602 				sizeof(efi_runtime_services_t));
603 	if (!runtime) {
604 		pr_err("Could not map the runtime service table!\n");
605 		return -ENOMEM;
606 	}
607 	/*
608 	 * We will only need *early* access to the following
609 	 * EFI runtime service before set_virtual_address_map
610 	 * is invoked.
611 	 */
612 	efi_phys.set_virtual_address_map =
613 		(efi_set_virtual_address_map_t *)
614 		runtime->set_virtual_address_map;
615 
616 	early_iounmap(runtime, sizeof(efi_runtime_services_t));
617 
618 	return 0;
619 }
620 
621 static int __init efi_memmap_init(void)
622 {
623 	/* Map the EFI memory map */
624 	memmap.map = early_ioremap((unsigned long)memmap.phys_map,
625 				   memmap.nr_map * memmap.desc_size);
626 	if (memmap.map == NULL) {
627 		pr_err("Could not map the memory map!\n");
628 		return -ENOMEM;
629 	}
630 	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
631 
632 	if (add_efi_memmap)
633 		do_add_efi_memmap();
634 
635 	return 0;
636 }
637 
638 void __init efi_init(void)
639 {
640 	efi_char16_t *c16;
641 	char vendor[100] = "unknown";
642 	int i = 0;
643 	void *tmp;
644 
645 #ifdef CONFIG_X86_32
646 	if (boot_params.efi_info.efi_systab_hi ||
647 	    boot_params.efi_info.efi_memmap_hi) {
648 		pr_info("Table located above 4GB, disabling EFI.\n");
649 		efi_enabled = 0;
650 		return;
651 	}
652 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
653 	efi_native = !efi_64bit;
654 #else
655 	efi_phys.systab = (efi_system_table_t *)
656 			  (boot_params.efi_info.efi_systab |
657 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
658 	efi_native = efi_64bit;
659 #endif
660 
661 	if (efi_systab_init(efi_phys.systab)) {
662 		efi_enabled = 0;
663 		return;
664 	}
665 
666 	/*
667 	 * Show what we know for posterity
668 	 */
669 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
670 	if (c16) {
671 		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
672 			vendor[i] = *c16++;
673 		vendor[i] = '\0';
674 	} else
675 		pr_err("Could not map the firmware vendor!\n");
676 	early_iounmap(tmp, 2);
677 
678 	pr_info("EFI v%u.%.02u by %s\n",
679 		efi.systab->hdr.revision >> 16,
680 		efi.systab->hdr.revision & 0xffff, vendor);
681 
682 	if (efi_config_init(efi.systab->tables, efi.systab->nr_tables)) {
683 		efi_enabled = 0;
684 		return;
685 	}
686 
687 	/*
688 	 * Note: We currently don't support runtime services on an EFI
689 	 * that doesn't match the kernel 32/64-bit mode.
690 	 */
691 
692 	if (!efi_native)
693 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
694 	else if (efi_runtime_init()) {
695 		efi_enabled = 0;
696 		return;
697 	}
698 
699 	if (efi_memmap_init()) {
700 		efi_enabled = 0;
701 		return;
702 	}
703 	if (efi_native) {
704 		x86_platform.get_wallclock = efi_get_time;
705 		x86_platform.set_wallclock = efi_set_rtc_mmss;
706 	}
707 
708 #if EFI_DEBUG
709 	print_efi_memmap();
710 #endif
711 }
712 
713 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
714 {
715 	u64 addr, npages;
716 
717 	addr = md->virt_addr;
718 	npages = md->num_pages;
719 
720 	memrange_efi_to_native(&addr, &npages);
721 
722 	if (executable)
723 		set_memory_x(addr, npages);
724 	else
725 		set_memory_nx(addr, npages);
726 }
727 
728 static void __init runtime_code_page_mkexec(void)
729 {
730 	efi_memory_desc_t *md;
731 	void *p;
732 
733 	/* Make EFI runtime service code area executable */
734 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
735 		md = p;
736 
737 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
738 			continue;
739 
740 		efi_set_executable(md, true);
741 	}
742 }
743 
744 /*
745  * This function will switch the EFI runtime services to virtual mode.
746  * Essentially, look through the EFI memmap and map every region that
747  * has the runtime attribute bit set in its memory descriptor and update
748  * that memory descriptor with the virtual address obtained from ioremap().
749  * This enables the runtime services to be called without having to
750  * thunk back into physical mode for every invocation.
751  */
752 void __init efi_enter_virtual_mode(void)
753 {
754 	efi_memory_desc_t *md, *prev_md = NULL;
755 	efi_status_t status;
756 	unsigned long size;
757 	u64 end, systab, addr, npages, end_pfn;
758 	void *p, *va, *new_memmap = NULL;
759 	int count = 0;
760 
761 	efi.systab = NULL;
762 
763 	/*
764 	 * We don't do virtual mode, since we don't do runtime services, on
765 	 * non-native EFI
766 	 */
767 
768 	if (!efi_native)
769 		goto out;
770 
771 	/* Merge contiguous regions of the same type and attribute */
772 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
773 		u64 prev_size;
774 		md = p;
775 
776 		if (!prev_md) {
777 			prev_md = md;
778 			continue;
779 		}
780 
781 		if (prev_md->type != md->type ||
782 		    prev_md->attribute != md->attribute) {
783 			prev_md = md;
784 			continue;
785 		}
786 
787 		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
788 
789 		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
790 			prev_md->num_pages += md->num_pages;
791 			md->type = EFI_RESERVED_TYPE;
792 			md->attribute = 0;
793 			continue;
794 		}
795 		prev_md = md;
796 	}
797 
798 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
799 		md = p;
800 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
801 		    md->type != EFI_BOOT_SERVICES_CODE &&
802 		    md->type != EFI_BOOT_SERVICES_DATA)
803 			continue;
804 
805 		size = md->num_pages << EFI_PAGE_SHIFT;
806 		end = md->phys_addr + size;
807 
808 		end_pfn = PFN_UP(end);
809 		if (end_pfn <= max_low_pfn_mapped
810 		    || (end_pfn > (1UL << (32 - PAGE_SHIFT))
811 			&& end_pfn <= max_pfn_mapped))
812 			va = __va(md->phys_addr);
813 		else
814 			va = efi_ioremap(md->phys_addr, size, md->type);
815 
816 		md->virt_addr = (u64) (unsigned long) va;
817 
818 		if (!va) {
819 			pr_err("ioremap of 0x%llX failed!\n",
820 			       (unsigned long long)md->phys_addr);
821 			continue;
822 		}
823 
824 		if (!(md->attribute & EFI_MEMORY_WB)) {
825 			addr = md->virt_addr;
826 			npages = md->num_pages;
827 			memrange_efi_to_native(&addr, &npages);
828 			set_memory_uc(addr, npages);
829 		}
830 
831 		systab = (u64) (unsigned long) efi_phys.systab;
832 		if (md->phys_addr <= systab && systab < end) {
833 			systab += md->virt_addr - md->phys_addr;
834 			efi.systab = (efi_system_table_t *) (unsigned long) systab;
835 		}
836 		new_memmap = krealloc(new_memmap,
837 				      (count + 1) * memmap.desc_size,
838 				      GFP_KERNEL);
839 		memcpy(new_memmap + (count * memmap.desc_size), md,
840 		       memmap.desc_size);
841 		count++;
842 	}
843 
844 	BUG_ON(!efi.systab);
845 
846 	status = phys_efi_set_virtual_address_map(
847 		memmap.desc_size * count,
848 		memmap.desc_size,
849 		memmap.desc_version,
850 		(efi_memory_desc_t *)__pa(new_memmap));
851 
852 	if (status != EFI_SUCCESS) {
853 		pr_alert("Unable to switch EFI into virtual mode "
854 			 "(status=%lx)!\n", status);
855 		panic("EFI call to SetVirtualAddressMap() failed!");
856 	}
857 
858 	/*
859 	 * Thankfully, it does seem that no runtime services other than
860 	 * SetVirtualAddressMap() will touch boot services code, so we can
861 	 * get rid of it all at this point
862 	 */
863 	efi_free_boot_services();
864 
865 	/*
866 	 * Now that EFI is in virtual mode, update the function
867 	 * pointers in the runtime service table to the new virtual addresses.
868 	 *
869 	 * Call EFI services through wrapper functions.
870 	 */
871 	efi.get_time = virt_efi_get_time;
872 	efi.set_time = virt_efi_set_time;
873 	efi.get_wakeup_time = virt_efi_get_wakeup_time;
874 	efi.set_wakeup_time = virt_efi_set_wakeup_time;
875 	efi.get_variable = virt_efi_get_variable;
876 	efi.get_next_variable = virt_efi_get_next_variable;
877 	efi.set_variable = virt_efi_set_variable;
878 	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
879 	efi.reset_system = virt_efi_reset_system;
880 	efi.set_virtual_address_map = NULL;
881 	efi.query_variable_info = virt_efi_query_variable_info;
882 	efi.update_capsule = virt_efi_update_capsule;
883 	efi.query_capsule_caps = virt_efi_query_capsule_caps;
884 	if (__supported_pte_mask & _PAGE_NX)
885 		runtime_code_page_mkexec();
886 
887 out:
888 	early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
889 	memmap.map = NULL;
890 	kfree(new_memmap);
891 }
892 
893 /*
894  * Convenience functions to obtain memory types and attributes
895  */
896 u32 efi_mem_type(unsigned long phys_addr)
897 {
898 	efi_memory_desc_t *md;
899 	void *p;
900 
901 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
902 		md = p;
903 		if ((md->phys_addr <= phys_addr) &&
904 		    (phys_addr < (md->phys_addr +
905 				  (md->num_pages << EFI_PAGE_SHIFT))))
906 			return md->type;
907 	}
908 	return 0;
909 }
910 
911 u64 efi_mem_attributes(unsigned long phys_addr)
912 {
913 	efi_memory_desc_t *md;
914 	void *p;
915 
916 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
917 		md = p;
918 		if ((md->phys_addr <= phys_addr) &&
919 		    (phys_addr < (md->phys_addr +
920 				  (md->num_pages << EFI_PAGE_SHIFT))))
921 			return md->attribute;
922 	}
923 	return 0;
924 }
925