summaryrefslogtreecommitdiff
path: root/drivers/firmware/efi/efi-init.c
blob: 2c16080e1f71907c6f7b03434c4cd2ac47a6ea62 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
// SPDX-License-Identifier: GPL-2.0
/*
 * Extensible Firmware Interface
 *
 * Based on Extensible Firmware Interface Specification version 2.4
 *
 * Copyright (C) 2013 - 2015 Linaro Ltd.
 */

#define pr_fmt(fmt)	"efi: " fmt

#include <linux/efi.h>
#include <linux/fwnode.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_fdt.h>
#include <linux/platform_device.h>
#include <linux/screen_info.h>

#include <asm/efi.h>

unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;

static int __init is_memory(efi_memory_desc_t *md)
{
	if (md->attribute & (EFI_MEMORY_WB|EFI_MEMORY_WT|EFI_MEMORY_WC))
		return 1;
	return 0;
}

/*
 * Translate a EFI virtual address into a physical address: this is necessary,
 * as some data members of the EFI system table are virtually remapped after
 * SetVirtualAddressMap() has been called.
 */
static phys_addr_t __init efi_to_phys(unsigned long addr)
{
	efi_memory_desc_t *md;

	for_each_efi_memory_desc(md) {
		if (!(md->attribute & EFI_MEMORY_RUNTIME))
			continue;
		if (md->virt_addr == 0)
			/* no virtual mapping has been installed by the stub */
			break;
		if (md->virt_addr <= addr &&
		    (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT))
			return md->phys_addr + addr - md->virt_addr;
	}
	return addr;
}

extern __weak const efi_config_table_type_t efi_arch_tables[];

static void __init init_screen_info(void)
{
	struct screen_info *si;

	if (screen_info_table != EFI_INVALID_TABLE_ADDR) {
		si = early_memremap(screen_info_table, sizeof(*si));
		if (!si) {
			pr_err("Could not map screen_info config table\n");
			return;
		}
		screen_info = *si;
		memset(si, 0, sizeof(*si));
		early_memunmap(si, sizeof(*si));

		if (memblock_is_map_memory(screen_info.lfb_base))
			memblock_mark_nomap(screen_info.lfb_base,
					    screen_info.lfb_size);
	}
}

static int __init uefi_init(u64 efi_system_table)
{
	efi_config_table_t *config_tables;
	efi_system_table_t *systab;
	size_t table_size;
	int retval;

	systab = early_memremap_ro(efi_system_table, sizeof(efi_system_table_t));
	if (systab == NULL) {
		pr_warn("Unable to map EFI system table.\n");
		return -ENOMEM;
	}

	set_bit(EFI_BOOT, &efi.flags);
	if (IS_ENABLED(CONFIG_64BIT))
		set_bit(EFI_64BIT, &efi.flags);

	retval = efi_systab_check_header(&systab->hdr);
	if (retval)
		goto out;

	efi.runtime = systab->runtime;
	efi.runtime_version = systab->hdr.revision;

	efi_systab_report_header(&systab->hdr, efi_to_phys(systab->fw_vendor));

	table_size = sizeof(efi_config_table_t) * systab->nr_tables;
	config_tables = early_memremap_ro(efi_to_phys(systab->tables),
					  table_size);
	if (config_tables == NULL) {
		pr_warn("Unable to map EFI config table array.\n");
		retval = -ENOMEM;
		goto out;
	}
	retval = efi_config_parse_tables(config_tables, systab->nr_tables,
					 efi_arch_tables);

	early_memunmap(config_tables, table_size);
out:
	early_memunmap(systab, sizeof(efi_system_table_t));
	return retval;
}

/*
 * Return true for regions that can be used as System RAM.
 */
static __init int is_usable_memory(efi_memory_desc_t *md)
{
	switch (md->type) {
	case EFI_LOADER_CODE:
	case EFI_LOADER_DATA:
	case EFI_ACPI_RECLAIM_MEMORY:
	case EFI_BOOT_SERVICES_CODE:
	case EFI_BOOT_SERVICES_DATA:
	case EFI_CONVENTIONAL_MEMORY:
	case EFI_PERSISTENT_MEMORY:
		/*
		 * Special purpose memory is 'soft reserved', which means it
		 * is set aside initially, but can be hotplugged back in or
		 * be assigned to the dax driver after boot.
		 */
		if (efi_soft_reserve_enabled() &&
		    (md->attribute & EFI_MEMORY_SP))
			return false;

		/*
		 * According to the spec, these regions are no longer reserved
		 * after calling ExitBootServices(). However, we can only use
		 * them as System RAM if they can be mapped writeback cacheable.
		 */
		return (md->attribute & EFI_MEMORY_WB);
	default:
		break;
	}
	return false;
}

static __init void reserve_regions(void)
{
	efi_memory_desc_t *md;
	u64 paddr, npages, size;

	if (efi_enabled(EFI_DBG))
		pr_info("Processing EFI memory map:\n");

	/*
	 * Discard memblocks discovered so far: if there are any at this
	 * point, they originate from memory nodes in the DT, and UEFI
	 * uses its own memory map instead.
	 */
	memblock_dump_all();
	memblock_remove(0, PHYS_ADDR_MAX);

	for_each_efi_memory_desc(md) {
		paddr = md->phys_addr;
		npages = md->num_pages;

		if (efi_enabled(EFI_DBG)) {
			char buf[64];

			pr_info("  0x%012llx-0x%012llx %s\n",
				paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
				efi_md_typeattr_format(buf, sizeof(buf), md));
		}

		memrange_efi_to_native(&paddr, &npages);
		size = npages << PAGE_SHIFT;

		if (is_memory(md)) {
			early_init_dt_add_memory_arch(paddr, size);

			if (!is_usable_memory(md))
				memblock_mark_nomap(paddr, size);

			/* keep ACPI reclaim memory intact for kexec etc. */
			if (md->type == EFI_ACPI_RECLAIM_MEMORY)
				memblock_reserve(paddr, size);
		}
	}
}

void __init efi_init(void)
{
	struct efi_memory_map_data data;
	u64 efi_system_table;

	/* Grab UEFI information placed in FDT by stub */
	efi_system_table = efi_get_fdt_params(&data);
	if (!efi_system_table)
		return;

	if (efi_memmap_init_early(&data) < 0) {
		/*
		* If we are booting via UEFI, the UEFI memory map is the only
		* description of memory we have, so there is little point in
		* proceeding if we cannot access it.
		*/
		panic("Unable to map EFI memory map.\n");
	}

	WARN(efi.memmap.desc_version != 1,
	     "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
	      efi.memmap.desc_version);

	if (uefi_init(efi_system_table) < 0) {
		efi_memmap_unmap();
		return;
	}

	reserve_regions();
	/*
	 * For memblock manipulation, the cap should come after the memblock_add().
	 * And now, memblock is fully populated, it is time to do capping.
	 */
	early_init_dt_check_for_usable_mem_range();
	efi_find_mirror();
	efi_esrt_init();
	efi_mokvar_table_init();

	memblock_reserve(data.phys_map & PAGE_MASK,
			 PAGE_ALIGN(data.size + (data.phys_map & ~PAGE_MASK)));

	init_screen_info();
}