xref: /openbmc/linux/arch/x86/platform/efi/efi.c (revision e23feb16)
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/slab.h>
38 #include <linux/memblock.h>
39 #include <linux/spinlock.h>
40 #include <linux/uaccess.h>
41 #include <linux/time.h>
42 #include <linux/io.h>
43 #include <linux/reboot.h>
44 #include <linux/bcd.h>
45 
46 #include <asm/setup.h>
47 #include <asm/efi.h>
48 #include <asm/time.h>
49 #include <asm/cacheflush.h>
50 #include <asm/tlbflush.h>
51 #include <asm/x86_init.h>
52 #include <asm/rtc.h>
53 
54 #define EFI_DEBUG	1
55 
56 #define EFI_MIN_RESERVE 5120
57 
58 #define EFI_DUMMY_GUID \
59 	EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
60 
61 static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
62 
63 struct efi __read_mostly efi = {
64 	.mps        = EFI_INVALID_TABLE_ADDR,
65 	.acpi       = EFI_INVALID_TABLE_ADDR,
66 	.acpi20     = EFI_INVALID_TABLE_ADDR,
67 	.smbios     = EFI_INVALID_TABLE_ADDR,
68 	.sal_systab = EFI_INVALID_TABLE_ADDR,
69 	.boot_info  = EFI_INVALID_TABLE_ADDR,
70 	.hcdp       = EFI_INVALID_TABLE_ADDR,
71 	.uga        = EFI_INVALID_TABLE_ADDR,
72 	.uv_systab  = EFI_INVALID_TABLE_ADDR,
73 };
74 EXPORT_SYMBOL(efi);
75 
76 struct efi_memory_map memmap;
77 
78 static struct efi efi_phys __initdata;
79 static efi_system_table_t efi_systab __initdata;
80 
81 unsigned long x86_efi_facility;
82 
83 /*
84  * Returns 1 if 'facility' is enabled, 0 otherwise.
85  */
86 int efi_enabled(int facility)
87 {
88 	return test_bit(facility, &x86_efi_facility) != 0;
89 }
90 EXPORT_SYMBOL(efi_enabled);
91 
92 static bool __initdata disable_runtime = false;
93 static int __init setup_noefi(char *arg)
94 {
95 	disable_runtime = true;
96 	return 0;
97 }
98 early_param("noefi", setup_noefi);
99 
100 int add_efi_memmap;
101 EXPORT_SYMBOL(add_efi_memmap);
102 
103 static int __init setup_add_efi_memmap(char *arg)
104 {
105 	add_efi_memmap = 1;
106 	return 0;
107 }
108 early_param("add_efi_memmap", setup_add_efi_memmap);
109 
110 static bool efi_no_storage_paranoia;
111 
112 static int __init setup_storage_paranoia(char *arg)
113 {
114 	efi_no_storage_paranoia = true;
115 	return 0;
116 }
117 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
118 
119 
120 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
121 {
122 	unsigned long flags;
123 	efi_status_t status;
124 
125 	spin_lock_irqsave(&rtc_lock, flags);
126 	status = efi_call_virt2(get_time, tm, tc);
127 	spin_unlock_irqrestore(&rtc_lock, flags);
128 	return status;
129 }
130 
131 static efi_status_t virt_efi_set_time(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_virt1(set_time, tm);
138 	spin_unlock_irqrestore(&rtc_lock, flags);
139 	return status;
140 }
141 
142 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
143 					     efi_bool_t *pending,
144 					     efi_time_t *tm)
145 {
146 	unsigned long flags;
147 	efi_status_t status;
148 
149 	spin_lock_irqsave(&rtc_lock, flags);
150 	status = efi_call_virt3(get_wakeup_time,
151 				enabled, pending, tm);
152 	spin_unlock_irqrestore(&rtc_lock, flags);
153 	return status;
154 }
155 
156 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
157 {
158 	unsigned long flags;
159 	efi_status_t status;
160 
161 	spin_lock_irqsave(&rtc_lock, flags);
162 	status = efi_call_virt2(set_wakeup_time,
163 				enabled, tm);
164 	spin_unlock_irqrestore(&rtc_lock, flags);
165 	return status;
166 }
167 
168 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
169 					  efi_guid_t *vendor,
170 					  u32 *attr,
171 					  unsigned long *data_size,
172 					  void *data)
173 {
174 	return efi_call_virt5(get_variable,
175 			      name, vendor, attr,
176 			      data_size, data);
177 }
178 
179 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
180 					       efi_char16_t *name,
181 					       efi_guid_t *vendor)
182 {
183 	return efi_call_virt3(get_next_variable,
184 			      name_size, name, vendor);
185 }
186 
187 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
188 					  efi_guid_t *vendor,
189 					  u32 attr,
190 					  unsigned long data_size,
191 					  void *data)
192 {
193 	return efi_call_virt5(set_variable,
194 			      name, vendor, attr,
195 			      data_size, data);
196 }
197 
198 static efi_status_t virt_efi_query_variable_info(u32 attr,
199 						 u64 *storage_space,
200 						 u64 *remaining_space,
201 						 u64 *max_variable_size)
202 {
203 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
204 		return EFI_UNSUPPORTED;
205 
206 	return efi_call_virt4(query_variable_info, attr, storage_space,
207 			      remaining_space, max_variable_size);
208 }
209 
210 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
211 {
212 	return efi_call_virt1(get_next_high_mono_count, count);
213 }
214 
215 static void virt_efi_reset_system(int reset_type,
216 				  efi_status_t status,
217 				  unsigned long data_size,
218 				  efi_char16_t *data)
219 {
220 	efi_call_virt4(reset_system, reset_type, status,
221 		       data_size, data);
222 }
223 
224 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
225 					    unsigned long count,
226 					    unsigned long sg_list)
227 {
228 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
229 		return EFI_UNSUPPORTED;
230 
231 	return efi_call_virt3(update_capsule, capsules, count, sg_list);
232 }
233 
234 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
235 						unsigned long count,
236 						u64 *max_size,
237 						int *reset_type)
238 {
239 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
240 		return EFI_UNSUPPORTED;
241 
242 	return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
243 			      reset_type);
244 }
245 
246 static efi_status_t __init phys_efi_set_virtual_address_map(
247 	unsigned long memory_map_size,
248 	unsigned long descriptor_size,
249 	u32 descriptor_version,
250 	efi_memory_desc_t *virtual_map)
251 {
252 	efi_status_t status;
253 
254 	efi_call_phys_prelog();
255 	status = efi_call_phys4(efi_phys.set_virtual_address_map,
256 				memory_map_size, descriptor_size,
257 				descriptor_version, virtual_map);
258 	efi_call_phys_epilog();
259 	return status;
260 }
261 
262 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
263 					     efi_time_cap_t *tc)
264 {
265 	unsigned long flags;
266 	efi_status_t status;
267 
268 	spin_lock_irqsave(&rtc_lock, flags);
269 	efi_call_phys_prelog();
270 	status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
271 				virt_to_phys(tc));
272 	efi_call_phys_epilog();
273 	spin_unlock_irqrestore(&rtc_lock, flags);
274 	return status;
275 }
276 
277 int efi_set_rtc_mmss(const struct timespec *now)
278 {
279 	unsigned long nowtime = now->tv_sec;
280 	efi_status_t 	status;
281 	efi_time_t 	eft;
282 	efi_time_cap_t 	cap;
283 	struct rtc_time	tm;
284 
285 	status = efi.get_time(&eft, &cap);
286 	if (status != EFI_SUCCESS) {
287 		pr_err("Oops: efitime: can't read time!\n");
288 		return -1;
289 	}
290 
291 	rtc_time_to_tm(nowtime, &tm);
292 	if (!rtc_valid_tm(&tm)) {
293 		eft.year = tm.tm_year + 1900;
294 		eft.month = tm.tm_mon + 1;
295 		eft.day = tm.tm_mday;
296 		eft.minute = tm.tm_min;
297 		eft.second = tm.tm_sec;
298 		eft.nanosecond = 0;
299 	} else {
300 		printk(KERN_ERR
301 		       "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
302 		       __FUNCTION__, nowtime);
303 		return -1;
304 	}
305 
306 	status = efi.set_time(&eft);
307 	if (status != EFI_SUCCESS) {
308 		pr_err("Oops: efitime: can't write time!\n");
309 		return -1;
310 	}
311 	return 0;
312 }
313 
314 void efi_get_time(struct timespec *now)
315 {
316 	efi_status_t status;
317 	efi_time_t eft;
318 	efi_time_cap_t cap;
319 
320 	status = efi.get_time(&eft, &cap);
321 	if (status != EFI_SUCCESS)
322 		pr_err("Oops: efitime: can't read time!\n");
323 
324 	now->tv_sec = mktime(eft.year, eft.month, eft.day, eft.hour,
325 			     eft.minute, eft.second);
326 	now->tv_nsec = 0;
327 }
328 
329 /*
330  * Tell the kernel about the EFI memory map.  This might include
331  * more than the max 128 entries that can fit in the e820 legacy
332  * (zeropage) memory map.
333  */
334 
335 static void __init do_add_efi_memmap(void)
336 {
337 	void *p;
338 
339 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
340 		efi_memory_desc_t *md = p;
341 		unsigned long long start = md->phys_addr;
342 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
343 		int e820_type;
344 
345 		switch (md->type) {
346 		case EFI_LOADER_CODE:
347 		case EFI_LOADER_DATA:
348 		case EFI_BOOT_SERVICES_CODE:
349 		case EFI_BOOT_SERVICES_DATA:
350 		case EFI_CONVENTIONAL_MEMORY:
351 			if (md->attribute & EFI_MEMORY_WB)
352 				e820_type = E820_RAM;
353 			else
354 				e820_type = E820_RESERVED;
355 			break;
356 		case EFI_ACPI_RECLAIM_MEMORY:
357 			e820_type = E820_ACPI;
358 			break;
359 		case EFI_ACPI_MEMORY_NVS:
360 			e820_type = E820_NVS;
361 			break;
362 		case EFI_UNUSABLE_MEMORY:
363 			e820_type = E820_UNUSABLE;
364 			break;
365 		default:
366 			/*
367 			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
368 			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
369 			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
370 			 */
371 			e820_type = E820_RESERVED;
372 			break;
373 		}
374 		e820_add_region(start, size, e820_type);
375 	}
376 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
377 }
378 
379 int __init efi_memblock_x86_reserve_range(void)
380 {
381 	struct efi_info *e = &boot_params.efi_info;
382 	unsigned long pmap;
383 
384 #ifdef CONFIG_X86_32
385 	/* Can't handle data above 4GB at this time */
386 	if (e->efi_memmap_hi) {
387 		pr_err("Memory map is above 4GB, disabling EFI.\n");
388 		return -EINVAL;
389 	}
390 	pmap =  e->efi_memmap;
391 #else
392 	pmap = (e->efi_memmap |	((__u64)e->efi_memmap_hi << 32));
393 #endif
394 	memmap.phys_map		= (void *)pmap;
395 	memmap.nr_map		= e->efi_memmap_size /
396 				  e->efi_memdesc_size;
397 	memmap.desc_size	= e->efi_memdesc_size;
398 	memmap.desc_version	= e->efi_memdesc_version;
399 
400 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
401 
402 	return 0;
403 }
404 
405 #if EFI_DEBUG
406 static void __init print_efi_memmap(void)
407 {
408 	efi_memory_desc_t *md;
409 	void *p;
410 	int i;
411 
412 	for (p = memmap.map, i = 0;
413 	     p < memmap.map_end;
414 	     p += memmap.desc_size, i++) {
415 		md = p;
416 		pr_info("mem%02u: type=%u, attr=0x%llx, "
417 			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
418 			i, md->type, md->attribute, md->phys_addr,
419 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
420 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
421 	}
422 }
423 #endif  /*  EFI_DEBUG  */
424 
425 void __init efi_reserve_boot_services(void)
426 {
427 	void *p;
428 
429 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
430 		efi_memory_desc_t *md = p;
431 		u64 start = md->phys_addr;
432 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
433 
434 		if (md->type != EFI_BOOT_SERVICES_CODE &&
435 		    md->type != EFI_BOOT_SERVICES_DATA)
436 			continue;
437 		/* Only reserve where possible:
438 		 * - Not within any already allocated areas
439 		 * - Not over any memory area (really needed, if above?)
440 		 * - Not within any part of the kernel
441 		 * - Not the bios reserved area
442 		*/
443 		if ((start+size >= __pa_symbol(_text)
444 				&& start <= __pa_symbol(_end)) ||
445 			!e820_all_mapped(start, start+size, E820_RAM) ||
446 			memblock_is_region_reserved(start, size)) {
447 			/* Could not reserve, skip it */
448 			md->num_pages = 0;
449 			memblock_dbg("Could not reserve boot range "
450 					"[0x%010llx-0x%010llx]\n",
451 						start, start+size-1);
452 		} else
453 			memblock_reserve(start, size);
454 	}
455 }
456 
457 void __init efi_unmap_memmap(void)
458 {
459 	clear_bit(EFI_MEMMAP, &x86_efi_facility);
460 	if (memmap.map) {
461 		early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
462 		memmap.map = NULL;
463 	}
464 }
465 
466 void __init efi_free_boot_services(void)
467 {
468 	void *p;
469 
470 	if (!efi_is_native())
471 		return;
472 
473 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
474 		efi_memory_desc_t *md = p;
475 		unsigned long long start = md->phys_addr;
476 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
477 
478 		if (md->type != EFI_BOOT_SERVICES_CODE &&
479 		    md->type != EFI_BOOT_SERVICES_DATA)
480 			continue;
481 
482 		/* Could not reserve boot area */
483 		if (!size)
484 			continue;
485 
486 		free_bootmem_late(start, size);
487 	}
488 
489 	efi_unmap_memmap();
490 }
491 
492 static int __init efi_systab_init(void *phys)
493 {
494 	if (efi_enabled(EFI_64BIT)) {
495 		efi_system_table_64_t *systab64;
496 		u64 tmp = 0;
497 
498 		systab64 = early_ioremap((unsigned long)phys,
499 					 sizeof(*systab64));
500 		if (systab64 == NULL) {
501 			pr_err("Couldn't map the system table!\n");
502 			return -ENOMEM;
503 		}
504 
505 		efi_systab.hdr = systab64->hdr;
506 		efi_systab.fw_vendor = systab64->fw_vendor;
507 		tmp |= systab64->fw_vendor;
508 		efi_systab.fw_revision = systab64->fw_revision;
509 		efi_systab.con_in_handle = systab64->con_in_handle;
510 		tmp |= systab64->con_in_handle;
511 		efi_systab.con_in = systab64->con_in;
512 		tmp |= systab64->con_in;
513 		efi_systab.con_out_handle = systab64->con_out_handle;
514 		tmp |= systab64->con_out_handle;
515 		efi_systab.con_out = systab64->con_out;
516 		tmp |= systab64->con_out;
517 		efi_systab.stderr_handle = systab64->stderr_handle;
518 		tmp |= systab64->stderr_handle;
519 		efi_systab.stderr = systab64->stderr;
520 		tmp |= systab64->stderr;
521 		efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
522 		tmp |= systab64->runtime;
523 		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
524 		tmp |= systab64->boottime;
525 		efi_systab.nr_tables = systab64->nr_tables;
526 		efi_systab.tables = systab64->tables;
527 		tmp |= systab64->tables;
528 
529 		early_iounmap(systab64, sizeof(*systab64));
530 #ifdef CONFIG_X86_32
531 		if (tmp >> 32) {
532 			pr_err("EFI data located above 4GB, disabling EFI.\n");
533 			return -EINVAL;
534 		}
535 #endif
536 	} else {
537 		efi_system_table_32_t *systab32;
538 
539 		systab32 = early_ioremap((unsigned long)phys,
540 					 sizeof(*systab32));
541 		if (systab32 == NULL) {
542 			pr_err("Couldn't map the system table!\n");
543 			return -ENOMEM;
544 		}
545 
546 		efi_systab.hdr = systab32->hdr;
547 		efi_systab.fw_vendor = systab32->fw_vendor;
548 		efi_systab.fw_revision = systab32->fw_revision;
549 		efi_systab.con_in_handle = systab32->con_in_handle;
550 		efi_systab.con_in = systab32->con_in;
551 		efi_systab.con_out_handle = systab32->con_out_handle;
552 		efi_systab.con_out = systab32->con_out;
553 		efi_systab.stderr_handle = systab32->stderr_handle;
554 		efi_systab.stderr = systab32->stderr;
555 		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
556 		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
557 		efi_systab.nr_tables = systab32->nr_tables;
558 		efi_systab.tables = systab32->tables;
559 
560 		early_iounmap(systab32, sizeof(*systab32));
561 	}
562 
563 	efi.systab = &efi_systab;
564 
565 	/*
566 	 * Verify the EFI Table
567 	 */
568 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
569 		pr_err("System table signature incorrect!\n");
570 		return -EINVAL;
571 	}
572 	if ((efi.systab->hdr.revision >> 16) == 0)
573 		pr_err("Warning: System table version "
574 		       "%d.%02d, expected 1.00 or greater!\n",
575 		       efi.systab->hdr.revision >> 16,
576 		       efi.systab->hdr.revision & 0xffff);
577 
578 	return 0;
579 }
580 
581 static int __init efi_config_init(u64 tables, int nr_tables)
582 {
583 	void *config_tables, *tablep;
584 	int i, sz;
585 
586 	if (efi_enabled(EFI_64BIT))
587 		sz = sizeof(efi_config_table_64_t);
588 	else
589 		sz = sizeof(efi_config_table_32_t);
590 
591 	/*
592 	 * Let's see what config tables the firmware passed to us.
593 	 */
594 	config_tables = early_ioremap(tables, nr_tables * sz);
595 	if (config_tables == NULL) {
596 		pr_err("Could not map Configuration table!\n");
597 		return -ENOMEM;
598 	}
599 
600 	tablep = config_tables;
601 	pr_info("");
602 	for (i = 0; i < efi.systab->nr_tables; i++) {
603 		efi_guid_t guid;
604 		unsigned long table;
605 
606 		if (efi_enabled(EFI_64BIT)) {
607 			u64 table64;
608 			guid = ((efi_config_table_64_t *)tablep)->guid;
609 			table64 = ((efi_config_table_64_t *)tablep)->table;
610 			table = table64;
611 #ifdef CONFIG_X86_32
612 			if (table64 >> 32) {
613 				pr_cont("\n");
614 				pr_err("Table located above 4GB, disabling EFI.\n");
615 				early_iounmap(config_tables,
616 					      efi.systab->nr_tables * sz);
617 				return -EINVAL;
618 			}
619 #endif
620 		} else {
621 			guid = ((efi_config_table_32_t *)tablep)->guid;
622 			table = ((efi_config_table_32_t *)tablep)->table;
623 		}
624 		if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
625 			efi.mps = table;
626 			pr_cont(" MPS=0x%lx ", table);
627 		} else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
628 			efi.acpi20 = table;
629 			pr_cont(" ACPI 2.0=0x%lx ", table);
630 		} else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
631 			efi.acpi = table;
632 			pr_cont(" ACPI=0x%lx ", table);
633 		} else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
634 			efi.smbios = table;
635 			pr_cont(" SMBIOS=0x%lx ", table);
636 #ifdef CONFIG_X86_UV
637 		} else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
638 			efi.uv_systab = table;
639 			pr_cont(" UVsystab=0x%lx ", table);
640 #endif
641 		} else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
642 			efi.hcdp = table;
643 			pr_cont(" HCDP=0x%lx ", table);
644 		} else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
645 			efi.uga = table;
646 			pr_cont(" UGA=0x%lx ", table);
647 		}
648 		tablep += sz;
649 	}
650 	pr_cont("\n");
651 	early_iounmap(config_tables, efi.systab->nr_tables * sz);
652 	return 0;
653 }
654 
655 static int __init efi_runtime_init(void)
656 {
657 	efi_runtime_services_t *runtime;
658 
659 	/*
660 	 * Check out the runtime services table. We need to map
661 	 * the runtime services table so that we can grab the physical
662 	 * address of several of the EFI runtime functions, needed to
663 	 * set the firmware into virtual mode.
664 	 */
665 	runtime = early_ioremap((unsigned long)efi.systab->runtime,
666 				sizeof(efi_runtime_services_t));
667 	if (!runtime) {
668 		pr_err("Could not map the runtime service table!\n");
669 		return -ENOMEM;
670 	}
671 	/*
672 	 * We will only need *early* access to the following
673 	 * two EFI runtime services before set_virtual_address_map
674 	 * is invoked.
675 	 */
676 	efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
677 	efi_phys.set_virtual_address_map =
678 		(efi_set_virtual_address_map_t *)
679 		runtime->set_virtual_address_map;
680 	/*
681 	 * Make efi_get_time can be called before entering
682 	 * virtual mode.
683 	 */
684 	efi.get_time = phys_efi_get_time;
685 	early_iounmap(runtime, sizeof(efi_runtime_services_t));
686 
687 	return 0;
688 }
689 
690 static int __init efi_memmap_init(void)
691 {
692 	/* Map the EFI memory map */
693 	memmap.map = early_ioremap((unsigned long)memmap.phys_map,
694 				   memmap.nr_map * memmap.desc_size);
695 	if (memmap.map == NULL) {
696 		pr_err("Could not map the memory map!\n");
697 		return -ENOMEM;
698 	}
699 	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
700 
701 	if (add_efi_memmap)
702 		do_add_efi_memmap();
703 
704 	return 0;
705 }
706 
707 void __init efi_init(void)
708 {
709 	efi_char16_t *c16;
710 	char vendor[100] = "unknown";
711 	int i = 0;
712 	void *tmp;
713 
714 #ifdef CONFIG_X86_32
715 	if (boot_params.efi_info.efi_systab_hi ||
716 	    boot_params.efi_info.efi_memmap_hi) {
717 		pr_info("Table located above 4GB, disabling EFI.\n");
718 		return;
719 	}
720 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
721 #else
722 	efi_phys.systab = (efi_system_table_t *)
723 			  (boot_params.efi_info.efi_systab |
724 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
725 #endif
726 
727 	if (efi_systab_init(efi_phys.systab))
728 		return;
729 
730 	set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
731 
732 	/*
733 	 * Show what we know for posterity
734 	 */
735 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
736 	if (c16) {
737 		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
738 			vendor[i] = *c16++;
739 		vendor[i] = '\0';
740 	} else
741 		pr_err("Could not map the firmware vendor!\n");
742 	early_iounmap(tmp, 2);
743 
744 	pr_info("EFI v%u.%.02u by %s\n",
745 		efi.systab->hdr.revision >> 16,
746 		efi.systab->hdr.revision & 0xffff, vendor);
747 
748 	if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
749 		return;
750 
751 	set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
752 
753 	/*
754 	 * Note: We currently don't support runtime services on an EFI
755 	 * that doesn't match the kernel 32/64-bit mode.
756 	 */
757 
758 	if (!efi_is_native())
759 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
760 	else {
761 		if (disable_runtime || efi_runtime_init())
762 			return;
763 		set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
764 	}
765 
766 	if (efi_memmap_init())
767 		return;
768 
769 	set_bit(EFI_MEMMAP, &x86_efi_facility);
770 
771 #ifdef CONFIG_X86_32
772 	if (efi_is_native()) {
773 		x86_platform.get_wallclock = efi_get_time;
774 		x86_platform.set_wallclock = efi_set_rtc_mmss;
775 	}
776 #endif
777 
778 #if EFI_DEBUG
779 	print_efi_memmap();
780 #endif
781 }
782 
783 void __init efi_late_init(void)
784 {
785 	efi_bgrt_init();
786 }
787 
788 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
789 {
790 	u64 addr, npages;
791 
792 	addr = md->virt_addr;
793 	npages = md->num_pages;
794 
795 	memrange_efi_to_native(&addr, &npages);
796 
797 	if (executable)
798 		set_memory_x(addr, npages);
799 	else
800 		set_memory_nx(addr, npages);
801 }
802 
803 static void __init runtime_code_page_mkexec(void)
804 {
805 	efi_memory_desc_t *md;
806 	void *p;
807 
808 	/* Make EFI runtime service code area executable */
809 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
810 		md = p;
811 
812 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
813 			continue;
814 
815 		efi_set_executable(md, true);
816 	}
817 }
818 
819 /*
820  * We can't ioremap data in EFI boot services RAM, because we've already mapped
821  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
822  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
823  */
824 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
825 {
826 	void *p;
827 	if (WARN_ON(!memmap.map))
828 		return NULL;
829 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
830 		efi_memory_desc_t *md = p;
831 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
832 		u64 end = md->phys_addr + size;
833 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
834 		    md->type != EFI_BOOT_SERVICES_CODE &&
835 		    md->type != EFI_BOOT_SERVICES_DATA)
836 			continue;
837 		if (!md->virt_addr)
838 			continue;
839 		if (phys_addr >= md->phys_addr && phys_addr < end) {
840 			phys_addr += md->virt_addr - md->phys_addr;
841 			return (__force void __iomem *)(unsigned long)phys_addr;
842 		}
843 	}
844 	return NULL;
845 }
846 
847 void efi_memory_uc(u64 addr, unsigned long size)
848 {
849 	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
850 	u64 npages;
851 
852 	npages = round_up(size, page_shift) / page_shift;
853 	memrange_efi_to_native(&addr, &npages);
854 	set_memory_uc(addr, npages);
855 }
856 
857 /*
858  * This function will switch the EFI runtime services to virtual mode.
859  * Essentially, look through the EFI memmap and map every region that
860  * has the runtime attribute bit set in its memory descriptor and update
861  * that memory descriptor with the virtual address obtained from ioremap().
862  * This enables the runtime services to be called without having to
863  * thunk back into physical mode for every invocation.
864  */
865 void __init efi_enter_virtual_mode(void)
866 {
867 	efi_memory_desc_t *md, *prev_md = NULL;
868 	efi_status_t status;
869 	unsigned long size;
870 	u64 end, systab, start_pfn, end_pfn;
871 	void *p, *va, *new_memmap = NULL;
872 	int count = 0;
873 
874 	efi.systab = NULL;
875 
876 	/*
877 	 * We don't do virtual mode, since we don't do runtime services, on
878 	 * non-native EFI
879 	 */
880 
881 	if (!efi_is_native()) {
882 		efi_unmap_memmap();
883 		return;
884 	}
885 
886 	/* Merge contiguous regions of the same type and attribute */
887 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
888 		u64 prev_size;
889 		md = p;
890 
891 		if (!prev_md) {
892 			prev_md = md;
893 			continue;
894 		}
895 
896 		if (prev_md->type != md->type ||
897 		    prev_md->attribute != md->attribute) {
898 			prev_md = md;
899 			continue;
900 		}
901 
902 		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
903 
904 		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
905 			prev_md->num_pages += md->num_pages;
906 			md->type = EFI_RESERVED_TYPE;
907 			md->attribute = 0;
908 			continue;
909 		}
910 		prev_md = md;
911 	}
912 
913 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
914 		md = p;
915 		if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
916 #ifdef CONFIG_X86_64
917 			if (md->type != EFI_BOOT_SERVICES_CODE &&
918 			    md->type != EFI_BOOT_SERVICES_DATA)
919 #endif
920 				continue;
921 		}
922 
923 		size = md->num_pages << EFI_PAGE_SHIFT;
924 		end = md->phys_addr + size;
925 
926 		start_pfn = PFN_DOWN(md->phys_addr);
927 		end_pfn = PFN_UP(end);
928 		if (pfn_range_is_mapped(start_pfn, end_pfn)) {
929 			va = __va(md->phys_addr);
930 
931 			if (!(md->attribute & EFI_MEMORY_WB))
932 				efi_memory_uc((u64)(unsigned long)va, size);
933 		} else
934 			va = efi_ioremap(md->phys_addr, size,
935 					 md->type, md->attribute);
936 
937 		md->virt_addr = (u64) (unsigned long) va;
938 
939 		if (!va) {
940 			pr_err("ioremap of 0x%llX failed!\n",
941 			       (unsigned long long)md->phys_addr);
942 			continue;
943 		}
944 
945 		systab = (u64) (unsigned long) efi_phys.systab;
946 		if (md->phys_addr <= systab && systab < end) {
947 			systab += md->virt_addr - md->phys_addr;
948 			efi.systab = (efi_system_table_t *) (unsigned long) systab;
949 		}
950 		new_memmap = krealloc(new_memmap,
951 				      (count + 1) * memmap.desc_size,
952 				      GFP_KERNEL);
953 		memcpy(new_memmap + (count * memmap.desc_size), md,
954 		       memmap.desc_size);
955 		count++;
956 	}
957 
958 	BUG_ON(!efi.systab);
959 
960 	status = phys_efi_set_virtual_address_map(
961 		memmap.desc_size * count,
962 		memmap.desc_size,
963 		memmap.desc_version,
964 		(efi_memory_desc_t *)__pa(new_memmap));
965 
966 	if (status != EFI_SUCCESS) {
967 		pr_alert("Unable to switch EFI into virtual mode "
968 			 "(status=%lx)!\n", status);
969 		panic("EFI call to SetVirtualAddressMap() failed!");
970 	}
971 
972 	/*
973 	 * Now that EFI is in virtual mode, update the function
974 	 * pointers in the runtime service table to the new virtual addresses.
975 	 *
976 	 * Call EFI services through wrapper functions.
977 	 */
978 	efi.runtime_version = efi_systab.hdr.revision;
979 	efi.get_time = virt_efi_get_time;
980 	efi.set_time = virt_efi_set_time;
981 	efi.get_wakeup_time = virt_efi_get_wakeup_time;
982 	efi.set_wakeup_time = virt_efi_set_wakeup_time;
983 	efi.get_variable = virt_efi_get_variable;
984 	efi.get_next_variable = virt_efi_get_next_variable;
985 	efi.set_variable = virt_efi_set_variable;
986 	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
987 	efi.reset_system = virt_efi_reset_system;
988 	efi.set_virtual_address_map = NULL;
989 	efi.query_variable_info = virt_efi_query_variable_info;
990 	efi.update_capsule = virt_efi_update_capsule;
991 	efi.query_capsule_caps = virt_efi_query_capsule_caps;
992 	if (__supported_pte_mask & _PAGE_NX)
993 		runtime_code_page_mkexec();
994 
995 	kfree(new_memmap);
996 
997 	/* clean DUMMY object */
998 	efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
999 			 EFI_VARIABLE_NON_VOLATILE |
1000 			 EFI_VARIABLE_BOOTSERVICE_ACCESS |
1001 			 EFI_VARIABLE_RUNTIME_ACCESS,
1002 			 0, NULL);
1003 }
1004 
1005 /*
1006  * Convenience functions to obtain memory types and attributes
1007  */
1008 u32 efi_mem_type(unsigned long phys_addr)
1009 {
1010 	efi_memory_desc_t *md;
1011 	void *p;
1012 
1013 	if (!efi_enabled(EFI_MEMMAP))
1014 		return 0;
1015 
1016 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1017 		md = p;
1018 		if ((md->phys_addr <= phys_addr) &&
1019 		    (phys_addr < (md->phys_addr +
1020 				  (md->num_pages << EFI_PAGE_SHIFT))))
1021 			return md->type;
1022 	}
1023 	return 0;
1024 }
1025 
1026 u64 efi_mem_attributes(unsigned long phys_addr)
1027 {
1028 	efi_memory_desc_t *md;
1029 	void *p;
1030 
1031 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1032 		md = p;
1033 		if ((md->phys_addr <= phys_addr) &&
1034 		    (phys_addr < (md->phys_addr +
1035 				  (md->num_pages << EFI_PAGE_SHIFT))))
1036 			return md->attribute;
1037 	}
1038 	return 0;
1039 }
1040 
1041 /*
1042  * Some firmware has serious problems when using more than 50% of the EFI
1043  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1044  * we never use more than this safe limit.
1045  *
1046  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1047  * store.
1048  */
1049 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1050 {
1051 	efi_status_t status;
1052 	u64 storage_size, remaining_size, max_size;
1053 
1054 	if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
1055 		return 0;
1056 
1057 	status = efi.query_variable_info(attributes, &storage_size,
1058 					 &remaining_size, &max_size);
1059 	if (status != EFI_SUCCESS)
1060 		return status;
1061 
1062 	/*
1063 	 * Some firmware implementations refuse to boot if there's insufficient
1064 	 * space in the variable store. We account for that by refusing the
1065 	 * write if permitting it would reduce the available space to under
1066 	 * 5KB. This figure was provided by Samsung, so should be safe.
1067 	 */
1068 	if ((remaining_size - size < EFI_MIN_RESERVE) &&
1069 		!efi_no_storage_paranoia) {
1070 
1071 		/*
1072 		 * Triggering garbage collection may require that the firmware
1073 		 * generate a real EFI_OUT_OF_RESOURCES error. We can force
1074 		 * that by attempting to use more space than is available.
1075 		 */
1076 		unsigned long dummy_size = remaining_size + 1024;
1077 		void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
1078 
1079 		if (!dummy)
1080 			return EFI_OUT_OF_RESOURCES;
1081 
1082 		status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1083 					  EFI_VARIABLE_NON_VOLATILE |
1084 					  EFI_VARIABLE_BOOTSERVICE_ACCESS |
1085 					  EFI_VARIABLE_RUNTIME_ACCESS,
1086 					  dummy_size, dummy);
1087 
1088 		if (status == EFI_SUCCESS) {
1089 			/*
1090 			 * This should have failed, so if it didn't make sure
1091 			 * that we delete it...
1092 			 */
1093 			efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1094 					 EFI_VARIABLE_NON_VOLATILE |
1095 					 EFI_VARIABLE_BOOTSERVICE_ACCESS |
1096 					 EFI_VARIABLE_RUNTIME_ACCESS,
1097 					 0, dummy);
1098 		}
1099 
1100 		kfree(dummy);
1101 
1102 		/*
1103 		 * The runtime code may now have triggered a garbage collection
1104 		 * run, so check the variable info again
1105 		 */
1106 		status = efi.query_variable_info(attributes, &storage_size,
1107 						 &remaining_size, &max_size);
1108 
1109 		if (status != EFI_SUCCESS)
1110 			return status;
1111 
1112 		/*
1113 		 * There still isn't enough room, so return an error
1114 		 */
1115 		if (remaining_size - size < EFI_MIN_RESERVE)
1116 			return EFI_OUT_OF_RESOURCES;
1117 	}
1118 
1119 	return EFI_SUCCESS;
1120 }
1121 EXPORT_SYMBOL_GPL(efi_query_variable_store);
1122