xref: /openbmc/linux/arch/x86/platform/efi/efi.c (revision f35e839a)
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 #include <linux/ucs2_string.h>
46 
47 #include <asm/setup.h>
48 #include <asm/efi.h>
49 #include <asm/time.h>
50 #include <asm/cacheflush.h>
51 #include <asm/tlbflush.h>
52 #include <asm/x86_init.h>
53 #include <asm/rtc.h>
54 
55 #define EFI_DEBUG	1
56 
57 /*
58  * There's some additional metadata associated with each
59  * variable. Intel's reference implementation is 60 bytes - bump that
60  * to account for potential alignment constraints
61  */
62 #define VAR_METADATA_SIZE 64
63 
64 struct efi __read_mostly efi = {
65 	.mps        = EFI_INVALID_TABLE_ADDR,
66 	.acpi       = EFI_INVALID_TABLE_ADDR,
67 	.acpi20     = EFI_INVALID_TABLE_ADDR,
68 	.smbios     = EFI_INVALID_TABLE_ADDR,
69 	.sal_systab = EFI_INVALID_TABLE_ADDR,
70 	.boot_info  = EFI_INVALID_TABLE_ADDR,
71 	.hcdp       = EFI_INVALID_TABLE_ADDR,
72 	.uga        = EFI_INVALID_TABLE_ADDR,
73 	.uv_systab  = EFI_INVALID_TABLE_ADDR,
74 };
75 EXPORT_SYMBOL(efi);
76 
77 struct efi_memory_map memmap;
78 
79 static struct efi efi_phys __initdata;
80 static efi_system_table_t efi_systab __initdata;
81 
82 static u64 efi_var_store_size;
83 static u64 efi_var_remaining_size;
84 static u64 efi_var_max_var_size;
85 static u64 boot_used_size;
86 static u64 boot_var_size;
87 static u64 active_size;
88 
89 unsigned long x86_efi_facility;
90 
91 /*
92  * Returns 1 if 'facility' is enabled, 0 otherwise.
93  */
94 int efi_enabled(int facility)
95 {
96 	return test_bit(facility, &x86_efi_facility) != 0;
97 }
98 EXPORT_SYMBOL(efi_enabled);
99 
100 static bool __initdata disable_runtime = false;
101 static int __init setup_noefi(char *arg)
102 {
103 	disable_runtime = true;
104 	return 0;
105 }
106 early_param("noefi", setup_noefi);
107 
108 int add_efi_memmap;
109 EXPORT_SYMBOL(add_efi_memmap);
110 
111 static int __init setup_add_efi_memmap(char *arg)
112 {
113 	add_efi_memmap = 1;
114 	return 0;
115 }
116 early_param("add_efi_memmap", setup_add_efi_memmap);
117 
118 static bool efi_no_storage_paranoia;
119 
120 static int __init setup_storage_paranoia(char *arg)
121 {
122 	efi_no_storage_paranoia = true;
123 	return 0;
124 }
125 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
126 
127 
128 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
129 {
130 	unsigned long flags;
131 	efi_status_t status;
132 
133 	spin_lock_irqsave(&rtc_lock, flags);
134 	status = efi_call_virt2(get_time, tm, tc);
135 	spin_unlock_irqrestore(&rtc_lock, flags);
136 	return status;
137 }
138 
139 static efi_status_t virt_efi_set_time(efi_time_t *tm)
140 {
141 	unsigned long flags;
142 	efi_status_t status;
143 
144 	spin_lock_irqsave(&rtc_lock, flags);
145 	status = efi_call_virt1(set_time, tm);
146 	spin_unlock_irqrestore(&rtc_lock, flags);
147 	return status;
148 }
149 
150 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
151 					     efi_bool_t *pending,
152 					     efi_time_t *tm)
153 {
154 	unsigned long flags;
155 	efi_status_t status;
156 
157 	spin_lock_irqsave(&rtc_lock, flags);
158 	status = efi_call_virt3(get_wakeup_time,
159 				enabled, pending, tm);
160 	spin_unlock_irqrestore(&rtc_lock, flags);
161 	return status;
162 }
163 
164 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
165 {
166 	unsigned long flags;
167 	efi_status_t status;
168 
169 	spin_lock_irqsave(&rtc_lock, flags);
170 	status = efi_call_virt2(set_wakeup_time,
171 				enabled, tm);
172 	spin_unlock_irqrestore(&rtc_lock, flags);
173 	return status;
174 }
175 
176 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
177 					  efi_guid_t *vendor,
178 					  u32 *attr,
179 					  unsigned long *data_size,
180 					  void *data)
181 {
182 	return efi_call_virt5(get_variable,
183 			      name, vendor, attr,
184 			      data_size, data);
185 }
186 
187 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
188 					       efi_char16_t *name,
189 					       efi_guid_t *vendor)
190 {
191 	efi_status_t status;
192 	static bool finished = false;
193 	static u64 var_size;
194 
195 	status = efi_call_virt3(get_next_variable,
196 				name_size, name, vendor);
197 
198 	if (status == EFI_NOT_FOUND) {
199 		finished = true;
200 		if (var_size < boot_used_size) {
201 			boot_var_size = boot_used_size - var_size;
202 			active_size += boot_var_size;
203 		} else {
204 			printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
205 		}
206 	}
207 
208 	if (boot_used_size && !finished) {
209 		unsigned long size;
210 		u32 attr;
211 		efi_status_t s;
212 		void *tmp;
213 
214 		s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
215 
216 		if (s != EFI_BUFFER_TOO_SMALL || !size)
217 			return status;
218 
219 		tmp = kmalloc(size, GFP_ATOMIC);
220 
221 		if (!tmp)
222 			return status;
223 
224 		s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
225 
226 		if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
227 			var_size += size;
228 			var_size += ucs2_strsize(name, 1024);
229 			active_size += size;
230 			active_size += VAR_METADATA_SIZE;
231 			active_size += ucs2_strsize(name, 1024);
232 		}
233 
234 		kfree(tmp);
235 	}
236 
237 	return status;
238 }
239 
240 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
241 					  efi_guid_t *vendor,
242 					  u32 attr,
243 					  unsigned long data_size,
244 					  void *data)
245 {
246 	efi_status_t status;
247 	u32 orig_attr = 0;
248 	unsigned long orig_size = 0;
249 
250 	status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
251 				       NULL);
252 
253 	if (status != EFI_BUFFER_TOO_SMALL)
254 		orig_size = 0;
255 
256 	status = efi_call_virt5(set_variable,
257 				name, vendor, attr,
258 				data_size, data);
259 
260 	if (status == EFI_SUCCESS) {
261 		if (orig_size) {
262 			active_size -= orig_size;
263 			active_size -= ucs2_strsize(name, 1024);
264 			active_size -= VAR_METADATA_SIZE;
265 		}
266 		if (data_size) {
267 			active_size += data_size;
268 			active_size += ucs2_strsize(name, 1024);
269 			active_size += VAR_METADATA_SIZE;
270 		}
271 	}
272 
273 	return status;
274 }
275 
276 static efi_status_t virt_efi_query_variable_info(u32 attr,
277 						 u64 *storage_space,
278 						 u64 *remaining_space,
279 						 u64 *max_variable_size)
280 {
281 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
282 		return EFI_UNSUPPORTED;
283 
284 	return efi_call_virt4(query_variable_info, attr, storage_space,
285 			      remaining_space, max_variable_size);
286 }
287 
288 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
289 {
290 	return efi_call_virt1(get_next_high_mono_count, count);
291 }
292 
293 static void virt_efi_reset_system(int reset_type,
294 				  efi_status_t status,
295 				  unsigned long data_size,
296 				  efi_char16_t *data)
297 {
298 	efi_call_virt4(reset_system, reset_type, status,
299 		       data_size, data);
300 }
301 
302 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
303 					    unsigned long count,
304 					    unsigned long sg_list)
305 {
306 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
307 		return EFI_UNSUPPORTED;
308 
309 	return efi_call_virt3(update_capsule, capsules, count, sg_list);
310 }
311 
312 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
313 						unsigned long count,
314 						u64 *max_size,
315 						int *reset_type)
316 {
317 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
318 		return EFI_UNSUPPORTED;
319 
320 	return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
321 			      reset_type);
322 }
323 
324 static efi_status_t __init phys_efi_set_virtual_address_map(
325 	unsigned long memory_map_size,
326 	unsigned long descriptor_size,
327 	u32 descriptor_version,
328 	efi_memory_desc_t *virtual_map)
329 {
330 	efi_status_t status;
331 
332 	efi_call_phys_prelog();
333 	status = efi_call_phys4(efi_phys.set_virtual_address_map,
334 				memory_map_size, descriptor_size,
335 				descriptor_version, virtual_map);
336 	efi_call_phys_epilog();
337 	return status;
338 }
339 
340 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
341 					     efi_time_cap_t *tc)
342 {
343 	unsigned long flags;
344 	efi_status_t status;
345 
346 	spin_lock_irqsave(&rtc_lock, flags);
347 	efi_call_phys_prelog();
348 	status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
349 				virt_to_phys(tc));
350 	efi_call_phys_epilog();
351 	spin_unlock_irqrestore(&rtc_lock, flags);
352 	return status;
353 }
354 
355 int efi_set_rtc_mmss(unsigned long nowtime)
356 {
357 	efi_status_t 	status;
358 	efi_time_t 	eft;
359 	efi_time_cap_t 	cap;
360 	struct rtc_time	tm;
361 
362 	status = efi.get_time(&eft, &cap);
363 	if (status != EFI_SUCCESS) {
364 		pr_err("Oops: efitime: can't read time!\n");
365 		return -1;
366 	}
367 
368 	rtc_time_to_tm(nowtime, &tm);
369 	if (!rtc_valid_tm(&tm)) {
370 		eft.year = tm.tm_year + 1900;
371 		eft.month = tm.tm_mon + 1;
372 		eft.day = tm.tm_mday;
373 		eft.minute = tm.tm_min;
374 		eft.second = tm.tm_sec;
375 		eft.nanosecond = 0;
376 	} else {
377 		printk(KERN_ERR
378 		       "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
379 		       __FUNCTION__, nowtime);
380 		return -1;
381 	}
382 
383 	status = efi.set_time(&eft);
384 	if (status != EFI_SUCCESS) {
385 		pr_err("Oops: efitime: can't write time!\n");
386 		return -1;
387 	}
388 	return 0;
389 }
390 
391 unsigned long efi_get_time(void)
392 {
393 	efi_status_t status;
394 	efi_time_t eft;
395 	efi_time_cap_t cap;
396 
397 	status = efi.get_time(&eft, &cap);
398 	if (status != EFI_SUCCESS)
399 		pr_err("Oops: efitime: can't read time!\n");
400 
401 	return mktime(eft.year, eft.month, eft.day, eft.hour,
402 		      eft.minute, eft.second);
403 }
404 
405 /*
406  * Tell the kernel about the EFI memory map.  This might include
407  * more than the max 128 entries that can fit in the e820 legacy
408  * (zeropage) memory map.
409  */
410 
411 static void __init do_add_efi_memmap(void)
412 {
413 	void *p;
414 
415 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
416 		efi_memory_desc_t *md = p;
417 		unsigned long long start = md->phys_addr;
418 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
419 		int e820_type;
420 
421 		switch (md->type) {
422 		case EFI_LOADER_CODE:
423 		case EFI_LOADER_DATA:
424 		case EFI_BOOT_SERVICES_CODE:
425 		case EFI_BOOT_SERVICES_DATA:
426 		case EFI_CONVENTIONAL_MEMORY:
427 			if (md->attribute & EFI_MEMORY_WB)
428 				e820_type = E820_RAM;
429 			else
430 				e820_type = E820_RESERVED;
431 			break;
432 		case EFI_ACPI_RECLAIM_MEMORY:
433 			e820_type = E820_ACPI;
434 			break;
435 		case EFI_ACPI_MEMORY_NVS:
436 			e820_type = E820_NVS;
437 			break;
438 		case EFI_UNUSABLE_MEMORY:
439 			e820_type = E820_UNUSABLE;
440 			break;
441 		default:
442 			/*
443 			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
444 			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
445 			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
446 			 */
447 			e820_type = E820_RESERVED;
448 			break;
449 		}
450 		e820_add_region(start, size, e820_type);
451 	}
452 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
453 }
454 
455 int __init efi_memblock_x86_reserve_range(void)
456 {
457 	struct efi_info *e = &boot_params.efi_info;
458 	unsigned long pmap;
459 
460 #ifdef CONFIG_X86_32
461 	/* Can't handle data above 4GB at this time */
462 	if (e->efi_memmap_hi) {
463 		pr_err("Memory map is above 4GB, disabling EFI.\n");
464 		return -EINVAL;
465 	}
466 	pmap =  e->efi_memmap;
467 #else
468 	pmap = (e->efi_memmap |	((__u64)e->efi_memmap_hi << 32));
469 #endif
470 	memmap.phys_map		= (void *)pmap;
471 	memmap.nr_map		= e->efi_memmap_size /
472 				  e->efi_memdesc_size;
473 	memmap.desc_size	= e->efi_memdesc_size;
474 	memmap.desc_version	= e->efi_memdesc_version;
475 
476 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
477 
478 	return 0;
479 }
480 
481 #if EFI_DEBUG
482 static void __init print_efi_memmap(void)
483 {
484 	efi_memory_desc_t *md;
485 	void *p;
486 	int i;
487 
488 	for (p = memmap.map, i = 0;
489 	     p < memmap.map_end;
490 	     p += memmap.desc_size, i++) {
491 		md = p;
492 		pr_info("mem%02u: type=%u, attr=0x%llx, "
493 			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
494 			i, md->type, md->attribute, md->phys_addr,
495 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
496 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
497 	}
498 }
499 #endif  /*  EFI_DEBUG  */
500 
501 void __init efi_reserve_boot_services(void)
502 {
503 	void *p;
504 
505 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
506 		efi_memory_desc_t *md = p;
507 		u64 start = md->phys_addr;
508 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
509 
510 		if (md->type != EFI_BOOT_SERVICES_CODE &&
511 		    md->type != EFI_BOOT_SERVICES_DATA)
512 			continue;
513 		/* Only reserve where possible:
514 		 * - Not within any already allocated areas
515 		 * - Not over any memory area (really needed, if above?)
516 		 * - Not within any part of the kernel
517 		 * - Not the bios reserved area
518 		*/
519 		if ((start+size >= __pa_symbol(_text)
520 				&& start <= __pa_symbol(_end)) ||
521 			!e820_all_mapped(start, start+size, E820_RAM) ||
522 			memblock_is_region_reserved(start, size)) {
523 			/* Could not reserve, skip it */
524 			md->num_pages = 0;
525 			memblock_dbg("Could not reserve boot range "
526 					"[0x%010llx-0x%010llx]\n",
527 						start, start+size-1);
528 		} else
529 			memblock_reserve(start, size);
530 	}
531 }
532 
533 void __init efi_unmap_memmap(void)
534 {
535 	clear_bit(EFI_MEMMAP, &x86_efi_facility);
536 	if (memmap.map) {
537 		early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
538 		memmap.map = NULL;
539 	}
540 }
541 
542 void __init efi_free_boot_services(void)
543 {
544 	void *p;
545 
546 	if (!efi_is_native())
547 		return;
548 
549 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
550 		efi_memory_desc_t *md = p;
551 		unsigned long long start = md->phys_addr;
552 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
553 
554 		if (md->type != EFI_BOOT_SERVICES_CODE &&
555 		    md->type != EFI_BOOT_SERVICES_DATA)
556 			continue;
557 
558 		/* Could not reserve boot area */
559 		if (!size)
560 			continue;
561 
562 		free_bootmem_late(start, size);
563 	}
564 
565 	efi_unmap_memmap();
566 }
567 
568 static int __init efi_systab_init(void *phys)
569 {
570 	if (efi_enabled(EFI_64BIT)) {
571 		efi_system_table_64_t *systab64;
572 		u64 tmp = 0;
573 
574 		systab64 = early_ioremap((unsigned long)phys,
575 					 sizeof(*systab64));
576 		if (systab64 == NULL) {
577 			pr_err("Couldn't map the system table!\n");
578 			return -ENOMEM;
579 		}
580 
581 		efi_systab.hdr = systab64->hdr;
582 		efi_systab.fw_vendor = systab64->fw_vendor;
583 		tmp |= systab64->fw_vendor;
584 		efi_systab.fw_revision = systab64->fw_revision;
585 		efi_systab.con_in_handle = systab64->con_in_handle;
586 		tmp |= systab64->con_in_handle;
587 		efi_systab.con_in = systab64->con_in;
588 		tmp |= systab64->con_in;
589 		efi_systab.con_out_handle = systab64->con_out_handle;
590 		tmp |= systab64->con_out_handle;
591 		efi_systab.con_out = systab64->con_out;
592 		tmp |= systab64->con_out;
593 		efi_systab.stderr_handle = systab64->stderr_handle;
594 		tmp |= systab64->stderr_handle;
595 		efi_systab.stderr = systab64->stderr;
596 		tmp |= systab64->stderr;
597 		efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
598 		tmp |= systab64->runtime;
599 		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
600 		tmp |= systab64->boottime;
601 		efi_systab.nr_tables = systab64->nr_tables;
602 		efi_systab.tables = systab64->tables;
603 		tmp |= systab64->tables;
604 
605 		early_iounmap(systab64, sizeof(*systab64));
606 #ifdef CONFIG_X86_32
607 		if (tmp >> 32) {
608 			pr_err("EFI data located above 4GB, disabling EFI.\n");
609 			return -EINVAL;
610 		}
611 #endif
612 	} else {
613 		efi_system_table_32_t *systab32;
614 
615 		systab32 = early_ioremap((unsigned long)phys,
616 					 sizeof(*systab32));
617 		if (systab32 == NULL) {
618 			pr_err("Couldn't map the system table!\n");
619 			return -ENOMEM;
620 		}
621 
622 		efi_systab.hdr = systab32->hdr;
623 		efi_systab.fw_vendor = systab32->fw_vendor;
624 		efi_systab.fw_revision = systab32->fw_revision;
625 		efi_systab.con_in_handle = systab32->con_in_handle;
626 		efi_systab.con_in = systab32->con_in;
627 		efi_systab.con_out_handle = systab32->con_out_handle;
628 		efi_systab.con_out = systab32->con_out;
629 		efi_systab.stderr_handle = systab32->stderr_handle;
630 		efi_systab.stderr = systab32->stderr;
631 		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
632 		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
633 		efi_systab.nr_tables = systab32->nr_tables;
634 		efi_systab.tables = systab32->tables;
635 
636 		early_iounmap(systab32, sizeof(*systab32));
637 	}
638 
639 	efi.systab = &efi_systab;
640 
641 	/*
642 	 * Verify the EFI Table
643 	 */
644 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
645 		pr_err("System table signature incorrect!\n");
646 		return -EINVAL;
647 	}
648 	if ((efi.systab->hdr.revision >> 16) == 0)
649 		pr_err("Warning: System table version "
650 		       "%d.%02d, expected 1.00 or greater!\n",
651 		       efi.systab->hdr.revision >> 16,
652 		       efi.systab->hdr.revision & 0xffff);
653 
654 	return 0;
655 }
656 
657 static int __init efi_config_init(u64 tables, int nr_tables)
658 {
659 	void *config_tables, *tablep;
660 	int i, sz;
661 
662 	if (efi_enabled(EFI_64BIT))
663 		sz = sizeof(efi_config_table_64_t);
664 	else
665 		sz = sizeof(efi_config_table_32_t);
666 
667 	/*
668 	 * Let's see what config tables the firmware passed to us.
669 	 */
670 	config_tables = early_ioremap(tables, nr_tables * sz);
671 	if (config_tables == NULL) {
672 		pr_err("Could not map Configuration table!\n");
673 		return -ENOMEM;
674 	}
675 
676 	tablep = config_tables;
677 	pr_info("");
678 	for (i = 0; i < efi.systab->nr_tables; i++) {
679 		efi_guid_t guid;
680 		unsigned long table;
681 
682 		if (efi_enabled(EFI_64BIT)) {
683 			u64 table64;
684 			guid = ((efi_config_table_64_t *)tablep)->guid;
685 			table64 = ((efi_config_table_64_t *)tablep)->table;
686 			table = table64;
687 #ifdef CONFIG_X86_32
688 			if (table64 >> 32) {
689 				pr_cont("\n");
690 				pr_err("Table located above 4GB, disabling EFI.\n");
691 				early_iounmap(config_tables,
692 					      efi.systab->nr_tables * sz);
693 				return -EINVAL;
694 			}
695 #endif
696 		} else {
697 			guid = ((efi_config_table_32_t *)tablep)->guid;
698 			table = ((efi_config_table_32_t *)tablep)->table;
699 		}
700 		if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
701 			efi.mps = table;
702 			pr_cont(" MPS=0x%lx ", table);
703 		} else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
704 			efi.acpi20 = table;
705 			pr_cont(" ACPI 2.0=0x%lx ", table);
706 		} else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
707 			efi.acpi = table;
708 			pr_cont(" ACPI=0x%lx ", table);
709 		} else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
710 			efi.smbios = table;
711 			pr_cont(" SMBIOS=0x%lx ", table);
712 #ifdef CONFIG_X86_UV
713 		} else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
714 			efi.uv_systab = table;
715 			pr_cont(" UVsystab=0x%lx ", table);
716 #endif
717 		} else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
718 			efi.hcdp = table;
719 			pr_cont(" HCDP=0x%lx ", table);
720 		} else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
721 			efi.uga = table;
722 			pr_cont(" UGA=0x%lx ", table);
723 		}
724 		tablep += sz;
725 	}
726 	pr_cont("\n");
727 	early_iounmap(config_tables, efi.systab->nr_tables * sz);
728 	return 0;
729 }
730 
731 static int __init efi_runtime_init(void)
732 {
733 	efi_runtime_services_t *runtime;
734 
735 	/*
736 	 * Check out the runtime services table. We need to map
737 	 * the runtime services table so that we can grab the physical
738 	 * address of several of the EFI runtime functions, needed to
739 	 * set the firmware into virtual mode.
740 	 */
741 	runtime = early_ioremap((unsigned long)efi.systab->runtime,
742 				sizeof(efi_runtime_services_t));
743 	if (!runtime) {
744 		pr_err("Could not map the runtime service table!\n");
745 		return -ENOMEM;
746 	}
747 	/*
748 	 * We will only need *early* access to the following
749 	 * two EFI runtime services before set_virtual_address_map
750 	 * is invoked.
751 	 */
752 	efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
753 	efi_phys.set_virtual_address_map =
754 		(efi_set_virtual_address_map_t *)
755 		runtime->set_virtual_address_map;
756 	/*
757 	 * Make efi_get_time can be called before entering
758 	 * virtual mode.
759 	 */
760 	efi.get_time = phys_efi_get_time;
761 	early_iounmap(runtime, sizeof(efi_runtime_services_t));
762 
763 	return 0;
764 }
765 
766 static int __init efi_memmap_init(void)
767 {
768 	/* Map the EFI memory map */
769 	memmap.map = early_ioremap((unsigned long)memmap.phys_map,
770 				   memmap.nr_map * memmap.desc_size);
771 	if (memmap.map == NULL) {
772 		pr_err("Could not map the memory map!\n");
773 		return -ENOMEM;
774 	}
775 	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
776 
777 	if (add_efi_memmap)
778 		do_add_efi_memmap();
779 
780 	return 0;
781 }
782 
783 void __init efi_init(void)
784 {
785 	efi_char16_t *c16;
786 	char vendor[100] = "unknown";
787 	int i = 0;
788 	void *tmp;
789 	struct setup_data *data;
790 	struct efi_var_bootdata *efi_var_data;
791 	u64 pa_data;
792 
793 #ifdef CONFIG_X86_32
794 	if (boot_params.efi_info.efi_systab_hi ||
795 	    boot_params.efi_info.efi_memmap_hi) {
796 		pr_info("Table located above 4GB, disabling EFI.\n");
797 		return;
798 	}
799 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
800 #else
801 	efi_phys.systab = (efi_system_table_t *)
802 			  (boot_params.efi_info.efi_systab |
803 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
804 #endif
805 
806 	if (efi_systab_init(efi_phys.systab))
807 		return;
808 
809 	pa_data = boot_params.hdr.setup_data;
810 	while (pa_data) {
811 		data = early_ioremap(pa_data, sizeof(*efi_var_data));
812 		if (data->type == SETUP_EFI_VARS) {
813 			efi_var_data = (struct efi_var_bootdata *)data;
814 
815 			efi_var_store_size = efi_var_data->store_size;
816 			efi_var_remaining_size = efi_var_data->remaining_size;
817 			efi_var_max_var_size = efi_var_data->max_var_size;
818 		}
819 		pa_data = data->next;
820 		early_iounmap(data, sizeof(*efi_var_data));
821 	}
822 
823 	boot_used_size = efi_var_store_size - efi_var_remaining_size;
824 
825 	set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
826 
827 	/*
828 	 * Show what we know for posterity
829 	 */
830 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
831 	if (c16) {
832 		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
833 			vendor[i] = *c16++;
834 		vendor[i] = '\0';
835 	} else
836 		pr_err("Could not map the firmware vendor!\n");
837 	early_iounmap(tmp, 2);
838 
839 	pr_info("EFI v%u.%.02u by %s\n",
840 		efi.systab->hdr.revision >> 16,
841 		efi.systab->hdr.revision & 0xffff, vendor);
842 
843 	if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
844 		return;
845 
846 	set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
847 
848 	/*
849 	 * Note: We currently don't support runtime services on an EFI
850 	 * that doesn't match the kernel 32/64-bit mode.
851 	 */
852 
853 	if (!efi_is_native())
854 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
855 	else {
856 		if (disable_runtime || efi_runtime_init())
857 			return;
858 		set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
859 	}
860 
861 	if (efi_memmap_init())
862 		return;
863 
864 	set_bit(EFI_MEMMAP, &x86_efi_facility);
865 
866 #ifdef CONFIG_X86_32
867 	if (efi_is_native()) {
868 		x86_platform.get_wallclock = efi_get_time;
869 		x86_platform.set_wallclock = efi_set_rtc_mmss;
870 	}
871 #endif
872 
873 #if EFI_DEBUG
874 	print_efi_memmap();
875 #endif
876 }
877 
878 void __init efi_late_init(void)
879 {
880 	efi_bgrt_init();
881 }
882 
883 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
884 {
885 	u64 addr, npages;
886 
887 	addr = md->virt_addr;
888 	npages = md->num_pages;
889 
890 	memrange_efi_to_native(&addr, &npages);
891 
892 	if (executable)
893 		set_memory_x(addr, npages);
894 	else
895 		set_memory_nx(addr, npages);
896 }
897 
898 static void __init runtime_code_page_mkexec(void)
899 {
900 	efi_memory_desc_t *md;
901 	void *p;
902 
903 	/* Make EFI runtime service code area executable */
904 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
905 		md = p;
906 
907 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
908 			continue;
909 
910 		efi_set_executable(md, true);
911 	}
912 }
913 
914 /*
915  * We can't ioremap data in EFI boot services RAM, because we've already mapped
916  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
917  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
918  */
919 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
920 {
921 	void *p;
922 	if (WARN_ON(!memmap.map))
923 		return NULL;
924 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
925 		efi_memory_desc_t *md = p;
926 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
927 		u64 end = md->phys_addr + size;
928 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
929 		    md->type != EFI_BOOT_SERVICES_CODE &&
930 		    md->type != EFI_BOOT_SERVICES_DATA)
931 			continue;
932 		if (!md->virt_addr)
933 			continue;
934 		if (phys_addr >= md->phys_addr && phys_addr < end) {
935 			phys_addr += md->virt_addr - md->phys_addr;
936 			return (__force void __iomem *)(unsigned long)phys_addr;
937 		}
938 	}
939 	return NULL;
940 }
941 
942 void efi_memory_uc(u64 addr, unsigned long size)
943 {
944 	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
945 	u64 npages;
946 
947 	npages = round_up(size, page_shift) / page_shift;
948 	memrange_efi_to_native(&addr, &npages);
949 	set_memory_uc(addr, npages);
950 }
951 
952 /*
953  * This function will switch the EFI runtime services to virtual mode.
954  * Essentially, look through the EFI memmap and map every region that
955  * has the runtime attribute bit set in its memory descriptor and update
956  * that memory descriptor with the virtual address obtained from ioremap().
957  * This enables the runtime services to be called without having to
958  * thunk back into physical mode for every invocation.
959  */
960 void __init efi_enter_virtual_mode(void)
961 {
962 	efi_memory_desc_t *md, *prev_md = NULL;
963 	efi_status_t status;
964 	unsigned long size;
965 	u64 end, systab, start_pfn, end_pfn;
966 	void *p, *va, *new_memmap = NULL;
967 	int count = 0;
968 
969 	efi.systab = NULL;
970 
971 	/*
972 	 * We don't do virtual mode, since we don't do runtime services, on
973 	 * non-native EFI
974 	 */
975 
976 	if (!efi_is_native()) {
977 		efi_unmap_memmap();
978 		return;
979 	}
980 
981 	/* Merge contiguous regions of the same type and attribute */
982 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
983 		u64 prev_size;
984 		md = p;
985 
986 		if (!prev_md) {
987 			prev_md = md;
988 			continue;
989 		}
990 
991 		if (prev_md->type != md->type ||
992 		    prev_md->attribute != md->attribute) {
993 			prev_md = md;
994 			continue;
995 		}
996 
997 		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
998 
999 		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
1000 			prev_md->num_pages += md->num_pages;
1001 			md->type = EFI_RESERVED_TYPE;
1002 			md->attribute = 0;
1003 			continue;
1004 		}
1005 		prev_md = md;
1006 	}
1007 
1008 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1009 		md = p;
1010 		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1011 		    md->type != EFI_BOOT_SERVICES_CODE &&
1012 		    md->type != EFI_BOOT_SERVICES_DATA)
1013 			continue;
1014 
1015 		size = md->num_pages << EFI_PAGE_SHIFT;
1016 		end = md->phys_addr + size;
1017 
1018 		start_pfn = PFN_DOWN(md->phys_addr);
1019 		end_pfn = PFN_UP(end);
1020 		if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1021 			va = __va(md->phys_addr);
1022 
1023 			if (!(md->attribute & EFI_MEMORY_WB))
1024 				efi_memory_uc((u64)(unsigned long)va, size);
1025 		} else
1026 			va = efi_ioremap(md->phys_addr, size,
1027 					 md->type, md->attribute);
1028 
1029 		md->virt_addr = (u64) (unsigned long) va;
1030 
1031 		if (!va) {
1032 			pr_err("ioremap of 0x%llX failed!\n",
1033 			       (unsigned long long)md->phys_addr);
1034 			continue;
1035 		}
1036 
1037 		systab = (u64) (unsigned long) efi_phys.systab;
1038 		if (md->phys_addr <= systab && systab < end) {
1039 			systab += md->virt_addr - md->phys_addr;
1040 			efi.systab = (efi_system_table_t *) (unsigned long) systab;
1041 		}
1042 		new_memmap = krealloc(new_memmap,
1043 				      (count + 1) * memmap.desc_size,
1044 				      GFP_KERNEL);
1045 		memcpy(new_memmap + (count * memmap.desc_size), md,
1046 		       memmap.desc_size);
1047 		count++;
1048 	}
1049 
1050 	BUG_ON(!efi.systab);
1051 
1052 	status = phys_efi_set_virtual_address_map(
1053 		memmap.desc_size * count,
1054 		memmap.desc_size,
1055 		memmap.desc_version,
1056 		(efi_memory_desc_t *)__pa(new_memmap));
1057 
1058 	if (status != EFI_SUCCESS) {
1059 		pr_alert("Unable to switch EFI into virtual mode "
1060 			 "(status=%lx)!\n", status);
1061 		panic("EFI call to SetVirtualAddressMap() failed!");
1062 	}
1063 
1064 	/*
1065 	 * Now that EFI is in virtual mode, update the function
1066 	 * pointers in the runtime service table to the new virtual addresses.
1067 	 *
1068 	 * Call EFI services through wrapper functions.
1069 	 */
1070 	efi.runtime_version = efi_systab.hdr.revision;
1071 	efi.get_time = virt_efi_get_time;
1072 	efi.set_time = virt_efi_set_time;
1073 	efi.get_wakeup_time = virt_efi_get_wakeup_time;
1074 	efi.set_wakeup_time = virt_efi_set_wakeup_time;
1075 	efi.get_variable = virt_efi_get_variable;
1076 	efi.get_next_variable = virt_efi_get_next_variable;
1077 	efi.set_variable = virt_efi_set_variable;
1078 	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1079 	efi.reset_system = virt_efi_reset_system;
1080 	efi.set_virtual_address_map = NULL;
1081 	efi.query_variable_info = virt_efi_query_variable_info;
1082 	efi.update_capsule = virt_efi_update_capsule;
1083 	efi.query_capsule_caps = virt_efi_query_capsule_caps;
1084 	if (__supported_pte_mask & _PAGE_NX)
1085 		runtime_code_page_mkexec();
1086 
1087 	kfree(new_memmap);
1088 }
1089 
1090 /*
1091  * Convenience functions to obtain memory types and attributes
1092  */
1093 u32 efi_mem_type(unsigned long phys_addr)
1094 {
1095 	efi_memory_desc_t *md;
1096 	void *p;
1097 
1098 	if (!efi_enabled(EFI_MEMMAP))
1099 		return 0;
1100 
1101 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1102 		md = p;
1103 		if ((md->phys_addr <= phys_addr) &&
1104 		    (phys_addr < (md->phys_addr +
1105 				  (md->num_pages << EFI_PAGE_SHIFT))))
1106 			return md->type;
1107 	}
1108 	return 0;
1109 }
1110 
1111 u64 efi_mem_attributes(unsigned long phys_addr)
1112 {
1113 	efi_memory_desc_t *md;
1114 	void *p;
1115 
1116 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1117 		md = p;
1118 		if ((md->phys_addr <= phys_addr) &&
1119 		    (phys_addr < (md->phys_addr +
1120 				  (md->num_pages << EFI_PAGE_SHIFT))))
1121 			return md->attribute;
1122 	}
1123 	return 0;
1124 }
1125 
1126 /*
1127  * Some firmware has serious problems when using more than 50% of the EFI
1128  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1129  * we never use more than this safe limit.
1130  *
1131  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1132  * store.
1133  */
1134 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1135 {
1136 	efi_status_t status;
1137 	u64 storage_size, remaining_size, max_size;
1138 
1139 	status = efi.query_variable_info(attributes, &storage_size,
1140 					 &remaining_size, &max_size);
1141 	if (status != EFI_SUCCESS)
1142 		return status;
1143 
1144 	if (!max_size && remaining_size > size)
1145 		printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1146 			    " is returning MaxVariableSize=0\n");
1147 	/*
1148 	 * Some firmware implementations refuse to boot if there's insufficient
1149 	 * space in the variable store. We account for that by refusing the
1150 	 * write if permitting it would reduce the available space to under
1151 	 * 50%. However, some firmware won't reclaim variable space until
1152 	 * after the used (not merely the actively used) space drops below
1153 	 * a threshold. We can approximate that case with the value calculated
1154 	 * above. If both the firmware and our calculations indicate that the
1155 	 * available space would drop below 50%, refuse the write.
1156 	 */
1157 
1158 	if (!storage_size || size > remaining_size ||
1159 	    (max_size && size > max_size))
1160 		return EFI_OUT_OF_RESOURCES;
1161 
1162 	if (!efi_no_storage_paranoia &&
1163 	    ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1164 	     (remaining_size - size < storage_size / 2)))
1165 		return EFI_OUT_OF_RESOURCES;
1166 
1167 	return EFI_SUCCESS;
1168 }
1169 EXPORT_SYMBOL_GPL(efi_query_variable_store);
1170