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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Common EFI (Extensible Firmware Interface) support functions
  4 * Based on Extensible Firmware Interface Specification version 1.0
  5 *
  6 * Copyright (C) 1999 VA Linux Systems
  7 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
  8 * Copyright (C) 1999-2002 Hewlett-Packard Co.
  9 *	David Mosberger-Tang <davidm@hpl.hp.com>
 10 *	Stephane Eranian <eranian@hpl.hp.com>
 11 * Copyright (C) 2005-2008 Intel Co.
 12 *	Fenghua Yu <fenghua.yu@intel.com>
 13 *	Bibo Mao <bibo.mao@intel.com>
 14 *	Chandramouli Narayanan <mouli@linux.intel.com>
 15 *	Huang Ying <ying.huang@intel.com>
 16 * Copyright (C) 2013 SuSE Labs
 17 *	Borislav Petkov <bp@suse.de> - runtime services VA mapping
 18 *
 19 * Copied from efi_32.c to eliminate the duplicated code between EFI
 20 * 32/64 support code. --ying 2007-10-26
 21 *
 22 * All EFI Runtime Services are not implemented yet as EFI only
 23 * supports physical mode addressing on SoftSDV. This is to be fixed
 24 * in a future version.  --drummond 1999-07-20
 25 *
 26 * Implemented EFI runtime services and virtual mode calls.  --davidm
 27 *
 28 * Goutham Rao: <goutham.rao@intel.com>
 29 *	Skip non-WB memory and ignore empty memory ranges.
 30 */
 31
 32#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 33
 34#include <linux/kernel.h>
 35#include <linux/init.h>
 36#include <linux/efi.h>
 37#include <linux/efi-bgrt.h>
 38#include <linux/export.h>
 39#include <linux/memblock.h>
 40#include <linux/slab.h>
 
 41#include <linux/spinlock.h>
 42#include <linux/uaccess.h>
 43#include <linux/time.h>
 44#include <linux/io.h>
 45#include <linux/reboot.h>
 46#include <linux/bcd.h>
 47
 48#include <asm/setup.h>
 49#include <asm/efi.h>
 50#include <asm/e820/api.h>
 51#include <asm/time.h>
 
 52#include <asm/tlbflush.h>
 53#include <asm/x86_init.h>
 
 54#include <asm/uv/uv.h>
 55
 56static unsigned long efi_systab_phys __initdata;
 57static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR;
 58static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR;
 59static unsigned long efi_runtime, efi_nr_tables;
 60
 61unsigned long efi_fw_vendor, efi_config_table;
 62
 63static const efi_config_table_type_t arch_tables[] __initconst = {
 64	{EFI_PROPERTIES_TABLE_GUID,	&prop_phys,		"PROP"		},
 65	{UGA_IO_PROTOCOL_GUID,		&uga_phys,		"UGA"		},
 66#ifdef CONFIG_X86_UV
 67	{UV_SYSTEM_TABLE_GUID,		&uv_systab_phys,	"UVsystab"	},
 68#endif
 69	{},
 70};
 71
 72static const unsigned long * const efi_tables[] = {
 73	&efi.acpi,
 74	&efi.acpi20,
 75	&efi.smbios,
 76	&efi.smbios3,
 77	&uga_phys,
 78#ifdef CONFIG_X86_UV
 79	&uv_systab_phys,
 80#endif
 81	&efi_fw_vendor,
 82	&efi_runtime,
 83	&efi_config_table,
 84	&efi.esrt,
 85	&prop_phys,
 86	&efi_mem_attr_table,
 87#ifdef CONFIG_EFI_RCI2_TABLE
 88	&rci2_table_phys,
 89#endif
 90	&efi.tpm_log,
 91	&efi.tpm_final_log,
 92	&efi_rng_seed,
 93#ifdef CONFIG_LOAD_UEFI_KEYS
 94	&efi.mokvar_table,
 95#endif
 96#ifdef CONFIG_EFI_COCO_SECRET
 97	&efi.coco_secret,
 98#endif
 
 99};
100
101u64 efi_setup;		/* efi setup_data physical address */
102
103static int add_efi_memmap __initdata;
104static int __init setup_add_efi_memmap(char *arg)
105{
106	add_efi_memmap = 1;
107	return 0;
108}
109early_param("add_efi_memmap", setup_add_efi_memmap);
110
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
111/*
112 * Tell the kernel about the EFI memory map.  This might include
113 * more than the max 128 entries that can fit in the passed in e820
114 * legacy (zeropage) memory map, but the kernel's e820 table can hold
115 * E820_MAX_ENTRIES.
116 */
117
118static void __init do_add_efi_memmap(void)
119{
120	efi_memory_desc_t *md;
121
122	if (!efi_enabled(EFI_MEMMAP))
123		return;
124
125	for_each_efi_memory_desc(md) {
 
126		unsigned long long start = md->phys_addr;
127		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
128		int e820_type;
129
130		switch (md->type) {
131		case EFI_LOADER_CODE:
132		case EFI_LOADER_DATA:
133		case EFI_BOOT_SERVICES_CODE:
134		case EFI_BOOT_SERVICES_DATA:
135		case EFI_CONVENTIONAL_MEMORY:
136			if (efi_soft_reserve_enabled()
137			    && (md->attribute & EFI_MEMORY_SP))
138				e820_type = E820_TYPE_SOFT_RESERVED;
139			else if (md->attribute & EFI_MEMORY_WB)
140				e820_type = E820_TYPE_RAM;
141			else
142				e820_type = E820_TYPE_RESERVED;
143			break;
144		case EFI_ACPI_RECLAIM_MEMORY:
145			e820_type = E820_TYPE_ACPI;
146			break;
147		case EFI_ACPI_MEMORY_NVS:
148			e820_type = E820_TYPE_NVS;
149			break;
150		case EFI_UNUSABLE_MEMORY:
151			e820_type = E820_TYPE_UNUSABLE;
152			break;
153		case EFI_PERSISTENT_MEMORY:
154			e820_type = E820_TYPE_PMEM;
155			break;
156		default:
157			/*
158			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
159			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
160			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
161			 */
162			e820_type = E820_TYPE_RESERVED;
163			break;
164		}
165
166		e820__range_add(start, size, e820_type);
167	}
168	e820__update_table(e820_table);
169}
170
171/*
172 * Given add_efi_memmap defaults to 0 and there is no alternative
173 * e820 mechanism for soft-reserved memory, import the full EFI memory
174 * map if soft reservations are present and enabled. Otherwise, the
175 * mechanism to disable the kernel's consideration of EFI_MEMORY_SP is
176 * the efi=nosoftreserve option.
177 */
178static bool do_efi_soft_reserve(void)
179{
180	efi_memory_desc_t *md;
181
182	if (!efi_enabled(EFI_MEMMAP))
183		return false;
184
185	if (!efi_soft_reserve_enabled())
186		return false;
187
188	for_each_efi_memory_desc(md)
189		if (md->type == EFI_CONVENTIONAL_MEMORY &&
190		    (md->attribute & EFI_MEMORY_SP))
191			return true;
192	return false;
193}
194
195int __init efi_memblock_x86_reserve_range(void)
196{
197	struct efi_info *e = &boot_params.efi_info;
198	struct efi_memory_map_data data;
199	phys_addr_t pmap;
200	int rv;
201
202	if (efi_enabled(EFI_PARAVIRT))
203		return 0;
204
205	/* Can't handle firmware tables above 4GB on i386 */
206	if (IS_ENABLED(CONFIG_X86_32) && e->efi_memmap_hi > 0) {
 
207		pr_err("Memory map is above 4GB, disabling EFI.\n");
208		return -EINVAL;
209	}
210	pmap = (phys_addr_t)(e->efi_memmap | ((u64)e->efi_memmap_hi << 32));
211
212	data.phys_map		= pmap;
213	data.size 		= e->efi_memmap_size;
214	data.desc_size		= e->efi_memdesc_size;
215	data.desc_version	= e->efi_memdesc_version;
216
217	if (!efi_enabled(EFI_PARAVIRT)) {
218		rv = efi_memmap_init_early(&data);
219		if (rv)
220			return rv;
221	}
222
223	if (add_efi_memmap || do_efi_soft_reserve())
224		do_add_efi_memmap();
225
226	efi_fake_memmap_early();
227
228	WARN(efi.memmap.desc_version != 1,
229	     "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
230	     efi.memmap.desc_version);
231
232	memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
233	set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
234
235	return 0;
236}
237
238#define OVERFLOW_ADDR_SHIFT	(64 - EFI_PAGE_SHIFT)
239#define OVERFLOW_ADDR_MASK	(U64_MAX << OVERFLOW_ADDR_SHIFT)
240#define U64_HIGH_BIT		(~(U64_MAX >> 1))
241
242static bool __init efi_memmap_entry_valid(const efi_memory_desc_t *md, int i)
243{
244	u64 end = (md->num_pages << EFI_PAGE_SHIFT) + md->phys_addr - 1;
245	u64 end_hi = 0;
246	char buf[64];
247
248	if (md->num_pages == 0) {
249		end = 0;
250	} else if (md->num_pages > EFI_PAGES_MAX ||
251		   EFI_PAGES_MAX - md->num_pages <
252		   (md->phys_addr >> EFI_PAGE_SHIFT)) {
253		end_hi = (md->num_pages & OVERFLOW_ADDR_MASK)
254			>> OVERFLOW_ADDR_SHIFT;
255
256		if ((md->phys_addr & U64_HIGH_BIT) && !(end & U64_HIGH_BIT))
257			end_hi += 1;
258	} else {
259		return true;
260	}
261
262	pr_warn_once(FW_BUG "Invalid EFI memory map entries:\n");
 
 
 
263
264	if (end_hi) {
265		pr_warn("mem%02u: %s range=[0x%016llx-0x%llx%016llx] (invalid)\n",
266			i, efi_md_typeattr_format(buf, sizeof(buf), md),
267			md->phys_addr, end_hi, end);
268	} else {
269		pr_warn("mem%02u: %s range=[0x%016llx-0x%016llx] (invalid)\n",
270			i, efi_md_typeattr_format(buf, sizeof(buf), md),
271			md->phys_addr, end);
 
 
272	}
273	return false;
274}
275
276static void __init efi_clean_memmap(void)
277{
278	efi_memory_desc_t *out = efi.memmap.map;
279	const efi_memory_desc_t *in = out;
280	const efi_memory_desc_t *end = efi.memmap.map_end;
281	int i, n_removal;
282
283	for (i = n_removal = 0; in < end; i++) {
284		if (efi_memmap_entry_valid(in, i)) {
285			if (out != in)
286				memcpy(out, in, efi.memmap.desc_size);
287			out = (void *)out + efi.memmap.desc_size;
288		} else {
289			n_removal++;
290		}
291		in = (void *)in + efi.memmap.desc_size;
292	}
293
294	if (n_removal > 0) {
295		struct efi_memory_map_data data = {
296			.phys_map	= efi.memmap.phys_map,
297			.desc_version	= efi.memmap.desc_version,
298			.desc_size	= efi.memmap.desc_size,
299			.size		= efi.memmap.desc_size * (efi.memmap.nr_map - n_removal),
300			.flags		= 0,
301		};
302
303		pr_warn("Removing %d invalid memory map entries.\n", n_removal);
304		efi_memmap_install(&data);
305	}
306}
307
308/*
309 * Firmware can use EfiMemoryMappedIO to request that MMIO regions be
310 * mapped by the OS so they can be accessed by EFI runtime services, but
311 * should have no other significance to the OS (UEFI r2.10, sec 7.2).
312 * However, most bootloaders and EFI stubs convert EfiMemoryMappedIO
313 * regions to E820_TYPE_RESERVED entries, which prevent Linux from
314 * allocating space from them (see remove_e820_regions()).
315 *
316 * Some platforms use EfiMemoryMappedIO entries for PCI MMCONFIG space and
317 * PCI host bridge windows, which means Linux can't allocate BAR space for
318 * hot-added devices.
319 *
320 * Remove large EfiMemoryMappedIO regions from the E820 map to avoid this
321 * problem.
322 *
323 * Retain small EfiMemoryMappedIO regions because on some platforms, these
324 * describe non-window space that's included in host bridge _CRS.  If we
325 * assign that space to PCI devices, they don't work.
326 */
327static void __init efi_remove_e820_mmio(void)
328{
329	efi_memory_desc_t *md;
330	u64 size, start, end;
331	int i = 0;
 
332
333	for_each_efi_memory_desc(md) {
334		if (md->type == EFI_MEMORY_MAPPED_IO) {
335			size = md->num_pages << EFI_PAGE_SHIFT;
336			start = md->phys_addr;
337			end = start + size - 1;
338			if (size >= 256*1024) {
339				pr_info("Remove mem%02u: MMIO range=[0x%08llx-0x%08llx] (%lluMB) from e820 map\n",
340					i, start, end, size >> 20);
341				e820__range_remove(start, size,
342						   E820_TYPE_RESERVED, 1);
343			} else {
344				pr_info("Not removing mem%02u: MMIO range=[0x%08llx-0x%08llx] (%lluKB) from e820 map\n",
345					i, start, end, size >> 10);
346			}
347		}
348		i++;
349	}
350}
351
352void __init efi_print_memmap(void)
353{
354	efi_memory_desc_t *md;
355	int i = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
356
357	for_each_efi_memory_desc(md) {
358		char buf[64];
 
 
 
 
 
 
 
 
 
359
360		pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
361			i++, efi_md_typeattr_format(buf, sizeof(buf), md),
362			md->phys_addr,
363			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
364			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
365	}
 
 
 
 
 
 
 
 
366}
367
368static int __init efi_systab_init(unsigned long phys)
369{
370	int size = efi_enabled(EFI_64BIT) ? sizeof(efi_system_table_64_t)
371					  : sizeof(efi_system_table_32_t);
372	const efi_table_hdr_t *hdr;
373	bool over4g = false;
374	void *p;
375	int ret;
376
377	hdr = p = early_memremap_ro(phys, size);
378	if (p == NULL) {
379		pr_err("Couldn't map the system table!\n");
 
380		return -ENOMEM;
381	}
382
383	ret = efi_systab_check_header(hdr, 1);
384	if (ret) {
385		early_memunmap(p, size);
386		return ret;
387	}
 
 
 
 
388
389	if (efi_enabled(EFI_64BIT)) {
390		const efi_system_table_64_t *systab64 = p;
391
392		efi_runtime	= systab64->runtime;
393		over4g		= systab64->runtime > U32_MAX;
 
394
395		if (efi_setup) {
396			struct efi_setup_data *data;
 
 
 
 
397
398			data = early_memremap_ro(efi_setup, sizeof(*data));
399			if (!data) {
400				early_memunmap(p, size);
401				return -ENOMEM;
402			}
 
 
 
 
403
404			efi_fw_vendor		= (unsigned long)data->fw_vendor;
405			efi_config_table	= (unsigned long)data->tables;
406
407			over4g |= data->fw_vendor	> U32_MAX ||
408				  data->tables		> U32_MAX;
 
409
410			early_memunmap(data, sizeof(*data));
411		} else {
412			efi_fw_vendor		= systab64->fw_vendor;
413			efi_config_table	= systab64->tables;
 
 
 
 
 
 
 
 
 
414
415			over4g |= systab64->fw_vendor	> U32_MAX ||
416				  systab64->tables	> U32_MAX;
417		}
418		efi_nr_tables = systab64->nr_tables;
419	} else {
420		const efi_system_table_32_t *systab32 = p;
421
422		efi_fw_vendor		= systab32->fw_vendor;
423		efi_runtime		= systab32->runtime;
424		efi_config_table	= systab32->tables;
425		efi_nr_tables		= systab32->nr_tables;
426	}
427
428	efi.runtime_version = hdr->revision;
429
430	efi_systab_report_header(hdr, efi_fw_vendor);
431	early_memunmap(p, size);
432
433	if (IS_ENABLED(CONFIG_X86_32) && over4g) {
434		pr_err("EFI data located above 4GB, disabling EFI.\n");
435		return -EINVAL;
436	}
437
438	return 0;
439}
440
441static int __init efi_config_init(const efi_config_table_type_t *arch_tables)
442{
443	void *config_tables;
444	int sz, ret;
445
446	if (efi_nr_tables == 0)
447		return 0;
448
449	if (efi_enabled(EFI_64BIT))
450		sz = sizeof(efi_config_table_64_t);
451	else
452		sz = sizeof(efi_config_table_32_t);
453
454	/*
455	 * Let's see what config tables the firmware passed to us.
456	 */
457	config_tables = early_memremap(efi_config_table, efi_nr_tables * sz);
458	if (config_tables == NULL) {
459		pr_err("Could not map Configuration table!\n");
460		return -ENOMEM;
461	}
 
462
463	ret = efi_config_parse_tables(config_tables, efi_nr_tables,
464				      arch_tables);
465
466	early_memunmap(config_tables, efi_nr_tables * sz);
467	return ret;
 
468}
469
470void __init efi_init(void)
471{
472	if (IS_ENABLED(CONFIG_X86_32) &&
473	    (boot_params.efi_info.efi_systab_hi ||
474	     boot_params.efi_info.efi_memmap_hi)) {
 
 
 
 
 
475		pr_info("Table located above 4GB, disabling EFI.\n");
476		return;
477	}
 
 
 
 
 
 
478
479	efi_systab_phys = boot_params.efi_info.efi_systab |
480			  ((__u64)boot_params.efi_info.efi_systab_hi << 32);
481
482	if (efi_systab_init(efi_systab_phys))
483		return;
484
485	if (efi_reuse_config(efi_config_table, efi_nr_tables))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
486		return;
487
488	if (efi_config_init(arch_tables))
489		return;
490
491	/*
492	 * Note: We currently don't support runtime services on an EFI
493	 * that doesn't match the kernel 32/64-bit mode.
494	 */
495
496	if (!efi_runtime_supported())
497		pr_err("No EFI runtime due to 32/64-bit mismatch with kernel\n");
498
499	if (!efi_runtime_supported() || efi_runtime_disabled()) {
500		efi_memmap_unmap();
501		return;
502	}
 
 
503
504	/* Parse the EFI Properties table if it exists */
505	if (prop_phys != EFI_INVALID_TABLE_ADDR) {
506		efi_properties_table_t *tbl;
507
508		tbl = early_memremap_ro(prop_phys, sizeof(*tbl));
509		if (tbl == NULL) {
510			pr_err("Could not map Properties table!\n");
511		} else {
512			if (tbl->memory_protection_attribute &
513			    EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
514				set_bit(EFI_NX_PE_DATA, &efi.flags);
515
516			early_memunmap(tbl, sizeof(*tbl));
517		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
518	}
 
519
520	set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
521	efi_clean_memmap();
 
 
522
523	efi_remove_e820_mmio();
 
 
 
524
525	if (efi_enabled(EFI_DBG))
526		efi_print_memmap();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
527}
528
529/* Merge contiguous regions of the same type and attribute */
530static void __init efi_merge_regions(void)
531{
 
532	efi_memory_desc_t *md, *prev_md = NULL;
533
534	for_each_efi_memory_desc(md) {
535		u64 prev_size;
 
536
537		if (!prev_md) {
538			prev_md = md;
539			continue;
540		}
541
542		if (prev_md->type != md->type ||
543		    prev_md->attribute != md->attribute) {
544			prev_md = md;
545			continue;
546		}
547
548		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
549
550		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
551			prev_md->num_pages += md->num_pages;
552			md->type = EFI_RESERVED_TYPE;
553			md->attribute = 0;
554			continue;
555		}
556		prev_md = md;
557	}
558}
559
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
560static void *realloc_pages(void *old_memmap, int old_shift)
561{
562	void *ret;
563
564	ret = (void *)__get_free_pages(GFP_KERNEL, old_shift + 1);
565	if (!ret)
566		goto out;
567
568	/*
569	 * A first-time allocation doesn't have anything to copy.
570	 */
571	if (!old_memmap)
572		return ret;
573
574	memcpy(ret, old_memmap, PAGE_SIZE << old_shift);
575
576out:
577	free_pages((unsigned long)old_memmap, old_shift);
578	return ret;
579}
580
581/*
582 * Iterate the EFI memory map in reverse order because the regions
583 * will be mapped top-down. The end result is the same as if we had
584 * mapped things forward, but doesn't require us to change the
585 * existing implementation of efi_map_region().
586 */
587static inline void *efi_map_next_entry_reverse(void *entry)
588{
589	/* Initial call */
590	if (!entry)
591		return efi.memmap.map_end - efi.memmap.desc_size;
592
593	entry -= efi.memmap.desc_size;
594	if (entry < efi.memmap.map)
595		return NULL;
596
597	return entry;
598}
599
600/*
601 * efi_map_next_entry - Return the next EFI memory map descriptor
602 * @entry: Previous EFI memory map descriptor
603 *
604 * This is a helper function to iterate over the EFI memory map, which
605 * we do in different orders depending on the current configuration.
606 *
607 * To begin traversing the memory map @entry must be %NULL.
608 *
609 * Returns %NULL when we reach the end of the memory map.
610 */
611static void *efi_map_next_entry(void *entry)
612{
613	if (efi_enabled(EFI_64BIT)) {
614		/*
615		 * Starting in UEFI v2.5 the EFI_PROPERTIES_TABLE
616		 * config table feature requires us to map all entries
617		 * in the same order as they appear in the EFI memory
618		 * map. That is to say, entry N must have a lower
619		 * virtual address than entry N+1. This is because the
620		 * firmware toolchain leaves relative references in
621		 * the code/data sections, which are split and become
622		 * separate EFI memory regions. Mapping things
623		 * out-of-order leads to the firmware accessing
624		 * unmapped addresses.
625		 *
626		 * Since we need to map things this way whether or not
627		 * the kernel actually makes use of
628		 * EFI_PROPERTIES_TABLE, let's just switch to this
629		 * scheme by default for 64-bit.
630		 */
631		return efi_map_next_entry_reverse(entry);
632	}
633
634	/* Initial call */
635	if (!entry)
636		return efi.memmap.map;
637
638	entry += efi.memmap.desc_size;
639	if (entry >= efi.memmap.map_end)
640		return NULL;
641
642	return entry;
643}
644
645static bool should_map_region(efi_memory_desc_t *md)
646{
647	/*
648	 * Runtime regions always require runtime mappings (obviously).
649	 */
650	if (md->attribute & EFI_MEMORY_RUNTIME)
651		return true;
652
653	/*
654	 * 32-bit EFI doesn't suffer from the bug that requires us to
655	 * reserve boot services regions, and mixed mode support
656	 * doesn't exist for 32-bit kernels.
657	 */
658	if (IS_ENABLED(CONFIG_X86_32))
659		return false;
660
661	/*
662	 * EFI specific purpose memory may be reserved by default
663	 * depending on kernel config and boot options.
664	 */
665	if (md->type == EFI_CONVENTIONAL_MEMORY &&
666	    efi_soft_reserve_enabled() &&
667	    (md->attribute & EFI_MEMORY_SP))
668		return false;
669
670	/*
671	 * Map all of RAM so that we can access arguments in the 1:1
672	 * mapping when making EFI runtime calls.
673	 */
674	if (efi_is_mixed()) {
675		if (md->type == EFI_CONVENTIONAL_MEMORY ||
676		    md->type == EFI_LOADER_DATA ||
677		    md->type == EFI_LOADER_CODE)
678			return true;
679	}
680
681	/*
682	 * Map boot services regions as a workaround for buggy
683	 * firmware that accesses them even when they shouldn't.
684	 *
685	 * See efi_{reserve,free}_boot_services().
686	 */
687	if (md->type == EFI_BOOT_SERVICES_CODE ||
688	    md->type == EFI_BOOT_SERVICES_DATA)
689		return true;
690
691	return false;
692}
693
694/*
695 * Map the efi memory ranges of the runtime services and update new_mmap with
696 * virtual addresses.
697 */
698static void * __init efi_map_regions(int *count, int *pg_shift)
699{
700	void *p, *new_memmap = NULL;
701	unsigned long left = 0;
702	unsigned long desc_size;
703	efi_memory_desc_t *md;
704
705	desc_size = efi.memmap.desc_size;
706
707	p = NULL;
708	while ((p = efi_map_next_entry(p))) {
709		md = p;
710
711		if (!should_map_region(md))
712			continue;
 
 
 
 
713
714		efi_map_region(md);
 
715
716		if (left < desc_size) {
717			new_memmap = realloc_pages(new_memmap, *pg_shift);
718			if (!new_memmap)
719				return NULL;
720
721			left += PAGE_SIZE << *pg_shift;
722			(*pg_shift)++;
723		}
724
725		memcpy(new_memmap + (*count * desc_size), md, desc_size);
 
726
727		left -= desc_size;
728		(*count)++;
729	}
730
731	return new_memmap;
732}
733
734static void __init kexec_enter_virtual_mode(void)
735{
736#ifdef CONFIG_KEXEC_CORE
737	efi_memory_desc_t *md;
738	unsigned int num_pages;
 
 
 
739
740	/*
741	 * We don't do virtual mode, since we don't do runtime services, on
742	 * non-native EFI.
743	 */
744	if (efi_is_mixed()) {
745		efi_memmap_unmap();
746		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
747		return;
748	}
749
750	if (efi_alloc_page_tables()) {
751		pr_err("Failed to allocate EFI page tables\n");
752		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
753		return;
754	}
755
756	/*
757	* Map efi regions which were passed via setup_data. The virt_addr is a
758	* fixed addr which was used in first kernel of a kexec boot.
759	*/
760	for_each_efi_memory_desc(md)
 
761		efi_map_region_fixed(md); /* FIXME: add error handling */
 
 
762
763	/*
764	 * Unregister the early EFI memmap from efi_init() and install
765	 * the new EFI memory map.
766	 */
767	efi_memmap_unmap();
768
769	if (efi_memmap_init_late(efi.memmap.phys_map,
770				 efi.memmap.desc_size * efi.memmap.nr_map)) {
771		pr_err("Failed to remap late EFI memory map\n");
772		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
773		return;
774	}
775
776	num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
777	num_pages >>= PAGE_SHIFT;
778
779	if (efi_setup_page_tables(efi.memmap.phys_map, num_pages)) {
780		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
781		return;
782	}
783
784	efi_sync_low_kernel_mappings();
 
 
 
 
 
 
 
 
 
785	efi_native_runtime_setup();
 
 
 
 
 
 
 
 
786#endif
787}
788
789/*
790 * This function will switch the EFI runtime services to virtual mode.
791 * Essentially, we look through the EFI memmap and map every region that
792 * has the runtime attribute bit set in its memory descriptor into the
793 * efi_pgd page table.
794 *
 
 
 
 
 
 
795 * The new method does a pagetable switch in a preemption-safe manner
796 * so that we're in a different address space when calling a runtime
797 * function. For function arguments passing we do copy the PUDs of the
798 * kernel page table into efi_pgd prior to each call.
799 *
800 * Specially for kexec boot, efi runtime maps in previous kernel should
801 * be passed in via setup_data. In that case runtime ranges will be mapped
802 * to the same virtual addresses as the first kernel, see
803 * kexec_enter_virtual_mode().
804 */
805static void __init __efi_enter_virtual_mode(void)
806{
807	int count = 0, pg_shift = 0;
808	void *new_memmap = NULL;
809	efi_status_t status;
810	unsigned long pa;
 
811
812	if (efi_alloc_page_tables()) {
813		pr_err("Failed to allocate EFI page tables\n");
814		goto err;
 
815	}
816
817	efi_merge_regions();
818	new_memmap = efi_map_regions(&count, &pg_shift);
819	if (!new_memmap) {
820		pr_err("Error reallocating memory, EFI runtime non-functional!\n");
821		goto err;
 
822	}
823
824	pa = __pa(new_memmap);
825
826	/*
827	 * Unregister the early EFI memmap from efi_init() and install
828	 * the new EFI memory map that we are about to pass to the
829	 * firmware via SetVirtualAddressMap().
830	 */
831	efi_memmap_unmap();
832
833	if (efi_memmap_init_late(pa, efi.memmap.desc_size * count)) {
834		pr_err("Failed to remap late EFI memory map\n");
835		goto err;
836	}
837
838	if (efi_enabled(EFI_DBG)) {
839		pr_info("EFI runtime memory map:\n");
840		efi_print_memmap();
841	}
842
843	if (efi_setup_page_tables(pa, 1 << pg_shift))
844		goto err;
845
846	efi_sync_low_kernel_mappings();
847
848	status = efi_set_virtual_address_map(efi.memmap.desc_size * count,
849					     efi.memmap.desc_size,
850					     efi.memmap.desc_version,
851					     (efi_memory_desc_t *)pa,
852					     efi_systab_phys);
 
 
 
 
 
 
 
 
 
 
853	if (status != EFI_SUCCESS) {
854		pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n",
855		       status);
856		goto err;
857	}
858
859	efi_check_for_embedded_firmwares();
860	efi_free_boot_services();
 
 
 
 
 
861
862	if (!efi_is_mixed())
863		efi_native_runtime_setup();
864	else
865		efi_thunk_runtime_setup();
866
 
 
867	/*
868	 * Apply more restrictive page table mapping attributes now that
869	 * SVAM() has been called and the firmware has performed all
870	 * necessary relocation fixups for the new virtual addresses.
871	 */
872	efi_runtime_update_mappings();
 
 
 
 
 
 
 
 
 
 
 
 
873
874	/* clean DUMMY object */
875	efi_delete_dummy_variable();
876	return;
877
878err:
879	clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
880}
881
882void __init efi_enter_virtual_mode(void)
883{
884	if (efi_enabled(EFI_PARAVIRT))
885		return;
886
887	efi.runtime = (efi_runtime_services_t *)efi_runtime;
888
889	if (efi_setup)
890		kexec_enter_virtual_mode();
891	else
892		__efi_enter_virtual_mode();
893
894	efi_dump_pagetable();
895}
896
897bool efi_is_table_address(unsigned long phys_addr)
 
 
 
898{
899	unsigned int i;
900
901	if (phys_addr == EFI_INVALID_TABLE_ADDR)
902		return false;
903
904	for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
905		if (*(efi_tables[i]) == phys_addr)
906			return true;
907
908	return false;
 
 
 
 
 
 
 
909}
910
911char *efi_systab_show_arch(char *str)
912{
913	if (uga_phys != EFI_INVALID_TABLE_ADDR)
914		str += sprintf(str, "UGA=0x%lx\n", uga_phys);
915	return str;
916}
917
918#define EFI_FIELD(var) efi_ ## var
919
920#define EFI_ATTR_SHOW(name) \
921static ssize_t name##_show(struct kobject *kobj, \
922				struct kobj_attribute *attr, char *buf) \
923{ \
924	return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
925}
926
927EFI_ATTR_SHOW(fw_vendor);
928EFI_ATTR_SHOW(runtime);
929EFI_ATTR_SHOW(config_table);
930
931struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
932struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
933struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
934
935umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n)
936{
937	if (attr == &efi_attr_fw_vendor.attr) {
938		if (efi_enabled(EFI_PARAVIRT) ||
939				efi_fw_vendor == EFI_INVALID_TABLE_ADDR)
940			return 0;
941	} else if (attr == &efi_attr_runtime.attr) {
942		if (efi_runtime == EFI_INVALID_TABLE_ADDR)
943			return 0;
944	} else if (attr == &efi_attr_config_table.attr) {
945		if (efi_config_table == EFI_INVALID_TABLE_ADDR)
946			return 0;
947	}
948	return attr->mode;
949}
v4.6
 
   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 * Copyright (C) 2013 SuSE Labs
  16 *	Borislav Petkov <bp@suse.de> - runtime services VA mapping
  17 *
  18 * Copied from efi_32.c to eliminate the duplicated code between EFI
  19 * 32/64 support code. --ying 2007-10-26
  20 *
  21 * All EFI Runtime Services are not implemented yet as EFI only
  22 * supports physical mode addressing on SoftSDV. This is to be fixed
  23 * in a future version.  --drummond 1999-07-20
  24 *
  25 * Implemented EFI runtime services and virtual mode calls.  --davidm
  26 *
  27 * Goutham Rao: <goutham.rao@intel.com>
  28 *	Skip non-WB memory and ignore empty memory ranges.
  29 */
  30
  31#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  32
  33#include <linux/kernel.h>
  34#include <linux/init.h>
  35#include <linux/efi.h>
  36#include <linux/efi-bgrt.h>
  37#include <linux/export.h>
  38#include <linux/bootmem.h>
  39#include <linux/slab.h>
  40#include <linux/memblock.h>
  41#include <linux/spinlock.h>
  42#include <linux/uaccess.h>
  43#include <linux/time.h>
  44#include <linux/io.h>
  45#include <linux/reboot.h>
  46#include <linux/bcd.h>
  47
  48#include <asm/setup.h>
  49#include <asm/efi.h>
 
  50#include <asm/time.h>
  51#include <asm/cacheflush.h>
  52#include <asm/tlbflush.h>
  53#include <asm/x86_init.h>
  54#include <asm/rtc.h>
  55#include <asm/uv/uv.h>
  56
  57#define EFI_DEBUG
  58
  59struct efi_memory_map memmap;
 
 
 
 
 
 
 
 
 
 
 
 
  60
  61static struct efi efi_phys __initdata;
  62static efi_system_table_t efi_systab __initdata;
  63
  64static efi_config_table_type_t arch_tables[] __initdata = {
 
 
  65#ifdef CONFIG_X86_UV
  66	{UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  67#endif
  68	{NULL_GUID, NULL, NULL},
  69};
  70
  71u64 efi_setup;		/* efi setup_data physical address */
  72
  73static int add_efi_memmap __initdata;
  74static int __init setup_add_efi_memmap(char *arg)
  75{
  76	add_efi_memmap = 1;
  77	return 0;
  78}
  79early_param("add_efi_memmap", setup_add_efi_memmap);
  80
  81static efi_status_t __init phys_efi_set_virtual_address_map(
  82	unsigned long memory_map_size,
  83	unsigned long descriptor_size,
  84	u32 descriptor_version,
  85	efi_memory_desc_t *virtual_map)
  86{
  87	efi_status_t status;
  88	unsigned long flags;
  89	pgd_t *save_pgd;
  90
  91	save_pgd = efi_call_phys_prolog();
  92
  93	/* Disable interrupts around EFI calls: */
  94	local_irq_save(flags);
  95	status = efi_call_phys(efi_phys.set_virtual_address_map,
  96			       memory_map_size, descriptor_size,
  97			       descriptor_version, virtual_map);
  98	local_irq_restore(flags);
  99
 100	efi_call_phys_epilog(save_pgd);
 101
 102	return status;
 103}
 104
 105void efi_get_time(struct timespec *now)
 106{
 107	efi_status_t status;
 108	efi_time_t eft;
 109	efi_time_cap_t cap;
 110
 111	status = efi.get_time(&eft, &cap);
 112	if (status != EFI_SUCCESS)
 113		pr_err("Oops: efitime: can't read time!\n");
 114
 115	now->tv_sec = mktime(eft.year, eft.month, eft.day, eft.hour,
 116			     eft.minute, eft.second);
 117	now->tv_nsec = 0;
 118}
 119
 120void __init efi_find_mirror(void)
 121{
 122	void *p;
 123	u64 mirror_size = 0, total_size = 0;
 124
 125	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 126		efi_memory_desc_t *md = p;
 127		unsigned long long start = md->phys_addr;
 128		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 129
 130		total_size += size;
 131		if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
 132			memblock_mark_mirror(start, size);
 133			mirror_size += size;
 134		}
 135	}
 136	if (mirror_size)
 137		pr_info("Memory: %lldM/%lldM mirrored memory\n",
 138			mirror_size>>20, total_size>>20);
 139}
 140
 141/*
 142 * Tell the kernel about the EFI memory map.  This might include
 143 * more than the max 128 entries that can fit in the e820 legacy
 144 * (zeropage) memory map.
 
 145 */
 146
 147static void __init do_add_efi_memmap(void)
 148{
 149	void *p;
 
 
 
 150
 151	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 152		efi_memory_desc_t *md = p;
 153		unsigned long long start = md->phys_addr;
 154		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 155		int e820_type;
 156
 157		switch (md->type) {
 158		case EFI_LOADER_CODE:
 159		case EFI_LOADER_DATA:
 160		case EFI_BOOT_SERVICES_CODE:
 161		case EFI_BOOT_SERVICES_DATA:
 162		case EFI_CONVENTIONAL_MEMORY:
 163			if (md->attribute & EFI_MEMORY_WB)
 164				e820_type = E820_RAM;
 
 
 
 165			else
 166				e820_type = E820_RESERVED;
 167			break;
 168		case EFI_ACPI_RECLAIM_MEMORY:
 169			e820_type = E820_ACPI;
 170			break;
 171		case EFI_ACPI_MEMORY_NVS:
 172			e820_type = E820_NVS;
 173			break;
 174		case EFI_UNUSABLE_MEMORY:
 175			e820_type = E820_UNUSABLE;
 176			break;
 177		case EFI_PERSISTENT_MEMORY:
 178			e820_type = E820_PMEM;
 179			break;
 180		default:
 181			/*
 182			 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 183			 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 184			 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 185			 */
 186			e820_type = E820_RESERVED;
 187			break;
 188		}
 189		e820_add_region(start, size, e820_type);
 
 190	}
 191	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 192}
 193
 194int __init efi_memblock_x86_reserve_range(void)
 195{
 196	struct efi_info *e = &boot_params.efi_info;
 
 197	phys_addr_t pmap;
 
 198
 199	if (efi_enabled(EFI_PARAVIRT))
 200		return 0;
 201
 202#ifdef CONFIG_X86_32
 203	/* Can't handle data above 4GB at this time */
 204	if (e->efi_memmap_hi) {
 205		pr_err("Memory map is above 4GB, disabling EFI.\n");
 206		return -EINVAL;
 207	}
 208	pmap =  e->efi_memmap;
 209#else
 210	pmap = (e->efi_memmap |	((__u64)e->efi_memmap_hi << 32));
 211#endif
 212	memmap.phys_map		= pmap;
 213	memmap.nr_map		= e->efi_memmap_size /
 214				  e->efi_memdesc_size;
 215	memmap.desc_size	= e->efi_memdesc_size;
 216	memmap.desc_version	= e->efi_memdesc_version;
 
 
 
 
 
 
 
 
 217
 218	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 
 
 219
 220	efi.memmap = &memmap;
 
 221
 222	return 0;
 223}
 224
 225void __init efi_print_memmap(void)
 226{
 227#ifdef EFI_DEBUG
 228	efi_memory_desc_t *md;
 229	void *p;
 230	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 231
 232	for (p = memmap.map, i = 0;
 233	     p < memmap.map_end;
 234	     p += memmap.desc_size, i++) {
 235		char buf[64];
 236
 237		md = p;
 238		pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
 
 
 
 
 239			i, efi_md_typeattr_format(buf, sizeof(buf), md),
 240			md->phys_addr,
 241			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
 242			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 243	}
 244#endif  /*  EFI_DEBUG  */
 245}
 246
 247void __init efi_unmap_memmap(void)
 248{
 249	clear_bit(EFI_MEMMAP, &efi.flags);
 250	if (memmap.map) {
 251		early_memunmap(memmap.map, memmap.nr_map * memmap.desc_size);
 252		memmap.map = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 253	}
 254}
 255
 256static int __init efi_systab_init(void *phys)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 257{
 258	if (efi_enabled(EFI_64BIT)) {
 259		efi_system_table_64_t *systab64;
 260		struct efi_setup_data *data = NULL;
 261		u64 tmp = 0;
 262
 263		if (efi_setup) {
 264			data = early_memremap(efi_setup, sizeof(*data));
 265			if (!data)
 266				return -ENOMEM;
 267		}
 268		systab64 = early_memremap((unsigned long)phys,
 269					 sizeof(*systab64));
 270		if (systab64 == NULL) {
 271			pr_err("Couldn't map the system table!\n");
 272			if (data)
 273				early_memunmap(data, sizeof(*data));
 274			return -ENOMEM;
 
 
 275		}
 
 
 
 276
 277		efi_systab.hdr = systab64->hdr;
 278		efi_systab.fw_vendor = data ? (unsigned long)data->fw_vendor :
 279					      systab64->fw_vendor;
 280		tmp |= data ? data->fw_vendor : systab64->fw_vendor;
 281		efi_systab.fw_revision = systab64->fw_revision;
 282		efi_systab.con_in_handle = systab64->con_in_handle;
 283		tmp |= systab64->con_in_handle;
 284		efi_systab.con_in = systab64->con_in;
 285		tmp |= systab64->con_in;
 286		efi_systab.con_out_handle = systab64->con_out_handle;
 287		tmp |= systab64->con_out_handle;
 288		efi_systab.con_out = systab64->con_out;
 289		tmp |= systab64->con_out;
 290		efi_systab.stderr_handle = systab64->stderr_handle;
 291		tmp |= systab64->stderr_handle;
 292		efi_systab.stderr = systab64->stderr;
 293		tmp |= systab64->stderr;
 294		efi_systab.runtime = data ?
 295				     (void *)(unsigned long)data->runtime :
 296				     (void *)(unsigned long)systab64->runtime;
 297		tmp |= data ? data->runtime : systab64->runtime;
 298		efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 299		tmp |= systab64->boottime;
 300		efi_systab.nr_tables = systab64->nr_tables;
 301		efi_systab.tables = data ? (unsigned long)data->tables :
 302					   systab64->tables;
 303		tmp |= data ? data->tables : systab64->tables;
 304
 305		early_memunmap(systab64, sizeof(*systab64));
 306		if (data)
 307			early_memunmap(data, sizeof(*data));
 308#ifdef CONFIG_X86_32
 309		if (tmp >> 32) {
 310			pr_err("EFI data located above 4GB, disabling EFI.\n");
 311			return -EINVAL;
 312		}
 313#endif
 314	} else {
 315		efi_system_table_32_t *systab32;
 316
 317		systab32 = early_memremap((unsigned long)phys,
 318					 sizeof(*systab32));
 319		if (systab32 == NULL) {
 320			pr_err("Couldn't map the system table!\n");
 321			return -ENOMEM;
 322		}
 323
 324		efi_systab.hdr = systab32->hdr;
 325		efi_systab.fw_vendor = systab32->fw_vendor;
 326		efi_systab.fw_revision = systab32->fw_revision;
 327		efi_systab.con_in_handle = systab32->con_in_handle;
 328		efi_systab.con_in = systab32->con_in;
 329		efi_systab.con_out_handle = systab32->con_out_handle;
 330		efi_systab.con_out = systab32->con_out;
 331		efi_systab.stderr_handle = systab32->stderr_handle;
 332		efi_systab.stderr = systab32->stderr;
 333		efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 334		efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 335		efi_systab.nr_tables = systab32->nr_tables;
 336		efi_systab.tables = systab32->tables;
 337
 338		early_memunmap(systab32, sizeof(*systab32));
 339	}
 340
 341	efi.systab = &efi_systab;
 342
 343	/*
 344	 * Verify the EFI Table
 345	 */
 346	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 347		pr_err("System table signature incorrect!\n");
 348		return -EINVAL;
 349	}
 350	if ((efi.systab->hdr.revision >> 16) == 0)
 351		pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
 352		       efi.systab->hdr.revision >> 16,
 353		       efi.systab->hdr.revision & 0xffff);
 354
 355	set_bit(EFI_SYSTEM_TABLES, &efi.flags);
 356
 357	return 0;
 358}
 359
 360static int __init efi_runtime_init32(void)
 361{
 362	efi_runtime_services_32_t *runtime;
 
 
 
 
 
 363
 364	runtime = early_memremap((unsigned long)efi.systab->runtime,
 365			sizeof(efi_runtime_services_32_t));
 366	if (!runtime) {
 367		pr_err("Could not map the runtime service table!\n");
 368		return -ENOMEM;
 369	}
 370
 371	/*
 372	 * We will only need *early* access to the SetVirtualAddressMap
 373	 * EFI runtime service. All other runtime services will be called
 374	 * via the virtual mapping.
 375	 */
 376	efi_phys.set_virtual_address_map =
 377			(efi_set_virtual_address_map_t *)
 378			(unsigned long)runtime->set_virtual_address_map;
 379	early_memunmap(runtime, sizeof(efi_runtime_services_32_t));
 380
 381	return 0;
 382}
 383
 384static int __init efi_runtime_init64(void)
 385{
 386	efi_runtime_services_64_t *runtime;
 387
 388	runtime = early_memremap((unsigned long)efi.systab->runtime,
 389			sizeof(efi_runtime_services_64_t));
 390	if (!runtime) {
 391		pr_err("Could not map the runtime service table!\n");
 392		return -ENOMEM;
 393	}
 394
 395	/*
 396	 * We will only need *early* access to the SetVirtualAddressMap
 397	 * EFI runtime service. All other runtime services will be called
 398	 * via the virtual mapping.
 399	 */
 400	efi_phys.set_virtual_address_map =
 401			(efi_set_virtual_address_map_t *)
 402			(unsigned long)runtime->set_virtual_address_map;
 403	early_memunmap(runtime, sizeof(efi_runtime_services_64_t));
 404
 405	return 0;
 406}
 407
 408static int __init efi_runtime_init(void)
 409{
 410	int rv;
 411
 412	/*
 413	 * Check out the runtime services table. We need to map
 414	 * the runtime services table so that we can grab the physical
 415	 * address of several of the EFI runtime functions, needed to
 416	 * set the firmware into virtual mode.
 417	 *
 418	 * When EFI_PARAVIRT is in force then we could not map runtime
 419	 * service memory region because we do not have direct access to it.
 420	 * However, runtime services are available through proxy functions
 421	 * (e.g. in case of Xen dom0 EFI implementation they call special
 422	 * hypercall which executes relevant EFI functions) and that is why
 423	 * they are always enabled.
 424	 */
 425
 426	if (!efi_enabled(EFI_PARAVIRT)) {
 427		if (efi_enabled(EFI_64BIT))
 428			rv = efi_runtime_init64();
 429		else
 430			rv = efi_runtime_init32();
 
 431
 432		if (rv)
 433			return rv;
 
 
 434	}
 435
 436	set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 
 
 
 
 
 
 
 
 437
 438	return 0;
 439}
 440
 441static int __init efi_memmap_init(void)
 442{
 443	if (efi_enabled(EFI_PARAVIRT))
 
 
 
 444		return 0;
 445
 446	/* Map the EFI memory map */
 447	memmap.map = early_memremap((unsigned long)memmap.phys_map,
 448				   memmap.nr_map * memmap.desc_size);
 449	if (memmap.map == NULL) {
 450		pr_err("Could not map the memory map!\n");
 
 
 
 
 
 
 451		return -ENOMEM;
 452	}
 453	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 454
 455	if (add_efi_memmap)
 456		do_add_efi_memmap();
 457
 458	set_bit(EFI_MEMMAP, &efi.flags);
 459
 460	return 0;
 461}
 462
 463void __init efi_init(void)
 464{
 465	efi_char16_t *c16;
 466	char vendor[100] = "unknown";
 467	int i = 0;
 468	void *tmp;
 469
 470#ifdef CONFIG_X86_32
 471	if (boot_params.efi_info.efi_systab_hi ||
 472	    boot_params.efi_info.efi_memmap_hi) {
 473		pr_info("Table located above 4GB, disabling EFI.\n");
 474		return;
 475	}
 476	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 477#else
 478	efi_phys.systab = (efi_system_table_t *)
 479			  (boot_params.efi_info.efi_systab |
 480			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 481#endif
 482
 483	if (efi_systab_init(efi_phys.systab))
 
 
 
 484		return;
 485
 486	efi.config_table = (unsigned long)efi.systab->tables;
 487	efi.fw_vendor	 = (unsigned long)efi.systab->fw_vendor;
 488	efi.runtime	 = (unsigned long)efi.systab->runtime;
 489
 490	/*
 491	 * Show what we know for posterity
 492	 */
 493	c16 = tmp = early_memremap(efi.systab->fw_vendor, 2);
 494	if (c16) {
 495		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 496			vendor[i] = *c16++;
 497		vendor[i] = '\0';
 498	} else
 499		pr_err("Could not map the firmware vendor!\n");
 500	early_memunmap(tmp, 2);
 501
 502	pr_info("EFI v%u.%.02u by %s\n",
 503		efi.systab->hdr.revision >> 16,
 504		efi.systab->hdr.revision & 0xffff, vendor);
 505
 506	if (efi_reuse_config(efi.systab->tables, efi.systab->nr_tables))
 507		return;
 508
 509	if (efi_config_init(arch_tables))
 510		return;
 511
 512	/*
 513	 * Note: We currently don't support runtime services on an EFI
 514	 * that doesn't match the kernel 32/64-bit mode.
 515	 */
 516
 517	if (!efi_runtime_supported())
 518		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 519	else {
 520		if (efi_runtime_disabled() || efi_runtime_init())
 521			return;
 
 522	}
 523	if (efi_memmap_init())
 524		return;
 525
 526	if (efi_enabled(EFI_DBG))
 527		efi_print_memmap();
 
 528
 529	efi_esrt_init();
 530}
 
 
 
 
 
 531
 532void __init efi_late_init(void)
 533{
 534	efi_bgrt_init();
 535}
 536
 537void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 538{
 539	u64 addr, npages;
 540
 541	addr = md->virt_addr;
 542	npages = md->num_pages;
 543
 544	memrange_efi_to_native(&addr, &npages);
 545
 546	if (executable)
 547		set_memory_x(addr, npages);
 548	else
 549		set_memory_nx(addr, npages);
 550}
 551
 552void __init runtime_code_page_mkexec(void)
 553{
 554	efi_memory_desc_t *md;
 555	void *p;
 556
 557	/* Make EFI runtime service code area executable */
 558	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 559		md = p;
 560
 561		if (md->type != EFI_RUNTIME_SERVICES_CODE)
 562			continue;
 563
 564		efi_set_executable(md, true);
 565	}
 566}
 567
 568void __init efi_memory_uc(u64 addr, unsigned long size)
 569{
 570	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 571	u64 npages;
 572
 573	npages = round_up(size, page_shift) / page_shift;
 574	memrange_efi_to_native(&addr, &npages);
 575	set_memory_uc(addr, npages);
 576}
 577
 578void __init old_map_region(efi_memory_desc_t *md)
 579{
 580	u64 start_pfn, end_pfn, end;
 581	unsigned long size;
 582	void *va;
 583
 584	start_pfn = PFN_DOWN(md->phys_addr);
 585	size	  = md->num_pages << PAGE_SHIFT;
 586	end	  = md->phys_addr + size;
 587	end_pfn   = PFN_UP(end);
 588
 589	if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 590		va = __va(md->phys_addr);
 591
 592		if (!(md->attribute & EFI_MEMORY_WB))
 593			efi_memory_uc((u64)(unsigned long)va, size);
 594	} else
 595		va = efi_ioremap(md->phys_addr, size,
 596				 md->type, md->attribute);
 597
 598	md->virt_addr = (u64) (unsigned long) va;
 599	if (!va)
 600		pr_err("ioremap of 0x%llX failed!\n",
 601		       (unsigned long long)md->phys_addr);
 602}
 603
 604/* Merge contiguous regions of the same type and attribute */
 605static void __init efi_merge_regions(void)
 606{
 607	void *p;
 608	efi_memory_desc_t *md, *prev_md = NULL;
 609
 610	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 611		u64 prev_size;
 612		md = p;
 613
 614		if (!prev_md) {
 615			prev_md = md;
 616			continue;
 617		}
 618
 619		if (prev_md->type != md->type ||
 620		    prev_md->attribute != md->attribute) {
 621			prev_md = md;
 622			continue;
 623		}
 624
 625		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 626
 627		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 628			prev_md->num_pages += md->num_pages;
 629			md->type = EFI_RESERVED_TYPE;
 630			md->attribute = 0;
 631			continue;
 632		}
 633		prev_md = md;
 634	}
 635}
 636
 637static void __init get_systab_virt_addr(efi_memory_desc_t *md)
 638{
 639	unsigned long size;
 640	u64 end, systab;
 641
 642	size = md->num_pages << EFI_PAGE_SHIFT;
 643	end = md->phys_addr + size;
 644	systab = (u64)(unsigned long)efi_phys.systab;
 645	if (md->phys_addr <= systab && systab < end) {
 646		systab += md->virt_addr - md->phys_addr;
 647		efi.systab = (efi_system_table_t *)(unsigned long)systab;
 648	}
 649}
 650
 651static void __init save_runtime_map(void)
 652{
 653#ifdef CONFIG_KEXEC_CORE
 654	efi_memory_desc_t *md;
 655	void *tmp, *p, *q = NULL;
 656	int count = 0;
 657
 658	if (efi_enabled(EFI_OLD_MEMMAP))
 659		return;
 660
 661	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 662		md = p;
 663
 664		if (!(md->attribute & EFI_MEMORY_RUNTIME) ||
 665		    (md->type == EFI_BOOT_SERVICES_CODE) ||
 666		    (md->type == EFI_BOOT_SERVICES_DATA))
 667			continue;
 668		tmp = krealloc(q, (count + 1) * memmap.desc_size, GFP_KERNEL);
 669		if (!tmp)
 670			goto out;
 671		q = tmp;
 672
 673		memcpy(q + count * memmap.desc_size, md, memmap.desc_size);
 674		count++;
 675	}
 676
 677	efi_runtime_map_setup(q, count, memmap.desc_size);
 678	return;
 679
 680out:
 681	kfree(q);
 682	pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
 683#endif
 684}
 685
 686static void *realloc_pages(void *old_memmap, int old_shift)
 687{
 688	void *ret;
 689
 690	ret = (void *)__get_free_pages(GFP_KERNEL, old_shift + 1);
 691	if (!ret)
 692		goto out;
 693
 694	/*
 695	 * A first-time allocation doesn't have anything to copy.
 696	 */
 697	if (!old_memmap)
 698		return ret;
 699
 700	memcpy(ret, old_memmap, PAGE_SIZE << old_shift);
 701
 702out:
 703	free_pages((unsigned long)old_memmap, old_shift);
 704	return ret;
 705}
 706
 707/*
 708 * Iterate the EFI memory map in reverse order because the regions
 709 * will be mapped top-down. The end result is the same as if we had
 710 * mapped things forward, but doesn't require us to change the
 711 * existing implementation of efi_map_region().
 712 */
 713static inline void *efi_map_next_entry_reverse(void *entry)
 714{
 715	/* Initial call */
 716	if (!entry)
 717		return memmap.map_end - memmap.desc_size;
 718
 719	entry -= memmap.desc_size;
 720	if (entry < memmap.map)
 721		return NULL;
 722
 723	return entry;
 724}
 725
 726/*
 727 * efi_map_next_entry - Return the next EFI memory map descriptor
 728 * @entry: Previous EFI memory map descriptor
 729 *
 730 * This is a helper function to iterate over the EFI memory map, which
 731 * we do in different orders depending on the current configuration.
 732 *
 733 * To begin traversing the memory map @entry must be %NULL.
 734 *
 735 * Returns %NULL when we reach the end of the memory map.
 736 */
 737static void *efi_map_next_entry(void *entry)
 738{
 739	if (!efi_enabled(EFI_OLD_MEMMAP) && efi_enabled(EFI_64BIT)) {
 740		/*
 741		 * Starting in UEFI v2.5 the EFI_PROPERTIES_TABLE
 742		 * config table feature requires us to map all entries
 743		 * in the same order as they appear in the EFI memory
 744		 * map. That is to say, entry N must have a lower
 745		 * virtual address than entry N+1. This is because the
 746		 * firmware toolchain leaves relative references in
 747		 * the code/data sections, which are split and become
 748		 * separate EFI memory regions. Mapping things
 749		 * out-of-order leads to the firmware accessing
 750		 * unmapped addresses.
 751		 *
 752		 * Since we need to map things this way whether or not
 753		 * the kernel actually makes use of
 754		 * EFI_PROPERTIES_TABLE, let's just switch to this
 755		 * scheme by default for 64-bit.
 756		 */
 757		return efi_map_next_entry_reverse(entry);
 758	}
 759
 760	/* Initial call */
 761	if (!entry)
 762		return memmap.map;
 763
 764	entry += memmap.desc_size;
 765	if (entry >= memmap.map_end)
 766		return NULL;
 767
 768	return entry;
 769}
 770
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 771/*
 772 * Map the efi memory ranges of the runtime services and update new_mmap with
 773 * virtual addresses.
 774 */
 775static void * __init efi_map_regions(int *count, int *pg_shift)
 776{
 777	void *p, *new_memmap = NULL;
 778	unsigned long left = 0;
 
 779	efi_memory_desc_t *md;
 780
 
 
 781	p = NULL;
 782	while ((p = efi_map_next_entry(p))) {
 783		md = p;
 784		if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
 785#ifdef CONFIG_X86_64
 786			if (md->type != EFI_BOOT_SERVICES_CODE &&
 787			    md->type != EFI_BOOT_SERVICES_DATA)
 788#endif
 789				continue;
 790		}
 791
 792		efi_map_region(md);
 793		get_systab_virt_addr(md);
 794
 795		if (left < memmap.desc_size) {
 796			new_memmap = realloc_pages(new_memmap, *pg_shift);
 797			if (!new_memmap)
 798				return NULL;
 799
 800			left += PAGE_SIZE << *pg_shift;
 801			(*pg_shift)++;
 802		}
 803
 804		memcpy(new_memmap + (*count * memmap.desc_size), md,
 805		       memmap.desc_size);
 806
 807		left -= memmap.desc_size;
 808		(*count)++;
 809	}
 810
 811	return new_memmap;
 812}
 813
 814static void __init kexec_enter_virtual_mode(void)
 815{
 816#ifdef CONFIG_KEXEC_CORE
 817	efi_memory_desc_t *md;
 818	unsigned int num_pages;
 819	void *p;
 820
 821	efi.systab = NULL;
 822
 823	/*
 824	 * We don't do virtual mode, since we don't do runtime services, on
 825	 * non-native EFI
 826	 */
 827	if (!efi_is_native()) {
 828		efi_unmap_memmap();
 829		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 830		return;
 831	}
 832
 833	if (efi_alloc_page_tables()) {
 834		pr_err("Failed to allocate EFI page tables\n");
 835		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 836		return;
 837	}
 838
 839	/*
 840	* Map efi regions which were passed via setup_data. The virt_addr is a
 841	* fixed addr which was used in first kernel of a kexec boot.
 842	*/
 843	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 844		md = p;
 845		efi_map_region_fixed(md); /* FIXME: add error handling */
 846		get_systab_virt_addr(md);
 847	}
 848
 849	save_runtime_map();
 
 
 
 
 850
 851	BUG_ON(!efi.systab);
 
 
 
 
 
 852
 853	num_pages = ALIGN(memmap.nr_map * memmap.desc_size, PAGE_SIZE);
 854	num_pages >>= PAGE_SHIFT;
 855
 856	if (efi_setup_page_tables(memmap.phys_map, num_pages)) {
 857		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 858		return;
 859	}
 860
 861	efi_sync_low_kernel_mappings();
 862
 863	/*
 864	 * Now that EFI is in virtual mode, update the function
 865	 * pointers in the runtime service table to the new virtual addresses.
 866	 *
 867	 * Call EFI services through wrapper functions.
 868	 */
 869	efi.runtime_version = efi_systab.hdr.revision;
 870
 871	efi_native_runtime_setup();
 872
 873	efi.set_virtual_address_map = NULL;
 874
 875	if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
 876		runtime_code_page_mkexec();
 877
 878	/* clean DUMMY object */
 879	efi_delete_dummy_variable();
 880#endif
 881}
 882
 883/*
 884 * This function will switch the EFI runtime services to virtual mode.
 885 * Essentially, we look through the EFI memmap and map every region that
 886 * has the runtime attribute bit set in its memory descriptor into the
 887 * efi_pgd page table.
 888 *
 889 * The old method which used to update that memory descriptor with the
 890 * virtual address obtained from ioremap() is still supported when the
 891 * kernel is booted with efi=old_map on its command line. Same old
 892 * method enabled the runtime services to be called without having to
 893 * thunk back into physical mode for every invocation.
 894 *
 895 * The new method does a pagetable switch in a preemption-safe manner
 896 * so that we're in a different address space when calling a runtime
 897 * function. For function arguments passing we do copy the PUDs of the
 898 * kernel page table into efi_pgd prior to each call.
 899 *
 900 * Specially for kexec boot, efi runtime maps in previous kernel should
 901 * be passed in via setup_data. In that case runtime ranges will be mapped
 902 * to the same virtual addresses as the first kernel, see
 903 * kexec_enter_virtual_mode().
 904 */
 905static void __init __efi_enter_virtual_mode(void)
 906{
 907	int count = 0, pg_shift = 0;
 908	void *new_memmap = NULL;
 909	efi_status_t status;
 910
 911	efi.systab = NULL;
 912
 913	if (efi_alloc_page_tables()) {
 914		pr_err("Failed to allocate EFI page tables\n");
 915		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 916		return;
 917	}
 918
 919	efi_merge_regions();
 920	new_memmap = efi_map_regions(&count, &pg_shift);
 921	if (!new_memmap) {
 922		pr_err("Error reallocating memory, EFI runtime non-functional!\n");
 923		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 924		return;
 925	}
 926
 927	save_runtime_map();
 928
 929	BUG_ON(!efi.systab);
 
 
 
 
 
 930
 931	if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift)) {
 932		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 933		return;
 
 
 
 
 
 934	}
 935
 
 
 
 936	efi_sync_low_kernel_mappings();
 937
 938	if (efi_is_native()) {
 939		status = phys_efi_set_virtual_address_map(
 940				memmap.desc_size * count,
 941				memmap.desc_size,
 942				memmap.desc_version,
 943				(efi_memory_desc_t *)__pa(new_memmap));
 944	} else {
 945		status = efi_thunk_set_virtual_address_map(
 946				efi_phys.set_virtual_address_map,
 947				memmap.desc_size * count,
 948				memmap.desc_size,
 949				memmap.desc_version,
 950				(efi_memory_desc_t *)__pa(new_memmap));
 951	}
 952
 953	if (status != EFI_SUCCESS) {
 954		pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
 955			 status);
 956		panic("EFI call to SetVirtualAddressMap() failed!");
 957	}
 958
 959	/*
 960	 * Now that EFI is in virtual mode, update the function
 961	 * pointers in the runtime service table to the new virtual addresses.
 962	 *
 963	 * Call EFI services through wrapper functions.
 964	 */
 965	efi.runtime_version = efi_systab.hdr.revision;
 966
 967	if (efi_is_native())
 968		efi_native_runtime_setup();
 969	else
 970		efi_thunk_runtime_setup();
 971
 972	efi.set_virtual_address_map = NULL;
 973
 974	/*
 975	 * Apply more restrictive page table mapping attributes now that
 976	 * SVAM() has been called and the firmware has performed all
 977	 * necessary relocation fixups for the new virtual addresses.
 978	 */
 979	efi_runtime_update_mappings();
 980	efi_dump_pagetable();
 981
 982	/*
 983	 * We mapped the descriptor array into the EFI pagetable above
 984	 * but we're not unmapping it here because if we're running in
 985	 * EFI mixed mode we need all of memory to be accessible when
 986	 * we pass parameters to the EFI runtime services in the
 987	 * thunking code.
 988	 *
 989	 * efi_cleanup_page_tables(__pa(new_memmap), 1 << pg_shift);
 990	 */
 991	free_pages((unsigned long)new_memmap, pg_shift);
 992
 993	/* clean DUMMY object */
 994	efi_delete_dummy_variable();
 
 
 
 
 995}
 996
 997void __init efi_enter_virtual_mode(void)
 998{
 999	if (efi_enabled(EFI_PARAVIRT))
1000		return;
1001
 
 
1002	if (efi_setup)
1003		kexec_enter_virtual_mode();
1004	else
1005		__efi_enter_virtual_mode();
 
 
1006}
1007
1008/*
1009 * Convenience functions to obtain memory types and attributes
1010 */
1011u32 efi_mem_type(unsigned long phys_addr)
1012{
1013	efi_memory_desc_t *md;
1014	void *p;
 
 
1015
1016	if (!efi_enabled(EFI_MEMMAP))
1017		return 0;
 
1018
1019	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1020		md = p;
1021		if ((md->phys_addr <= phys_addr) &&
1022		    (phys_addr < (md->phys_addr +
1023				  (md->num_pages << EFI_PAGE_SHIFT))))
1024			return md->type;
1025	}
1026	return 0;
1027}
1028
1029static int __init arch_parse_efi_cmdline(char *str)
1030{
1031	if (!str) {
1032		pr_warn("need at least one option\n");
1033		return -EINVAL;
1034	}
 
 
 
 
 
 
 
 
 
 
 
 
 
1035
1036	if (parse_option_str(str, "old_map"))
1037		set_bit(EFI_OLD_MEMMAP, &efi.flags);
 
1038
1039	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
1040}
1041early_param("efi", arch_parse_efi_cmdline);