1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * EFI initialization
4 *
5 * Author: Jianmin Lv <lvjianmin@loongson.cn>
6 * Huacai Chen <chenhuacai@loongson.cn>
7 *
8 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
9 */
10
11 #include <linux/acpi.h>
12 #include <linux/efi.h>
13 #include <linux/efi-bgrt.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/export.h>
17 #include <linux/io.h>
18 #include <linux/kobject.h>
19 #include <linux/memblock.h>
20 #include <linux/reboot.h>
21 #include <linux/screen_info.h>
22 #include <linux/uaccess.h>
23
24 #include <asm/early_ioremap.h>
25 #include <asm/efi.h>
26 #include <asm/loongson.h>
27
28 static unsigned long efi_nr_tables;
29 static unsigned long efi_config_table;
30
31 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
32 static unsigned long __initdata fdt_pointer = EFI_INVALID_TABLE_ADDR;
33
34 static efi_system_table_t *efi_systab;
35 static efi_config_table_type_t arch_tables[] __initdata = {
36 {LINUX_EFI_BOOT_MEMMAP_GUID, &boot_memmap, "MEMMAP" },
37 {DEVICE_TREE_GUID, &fdt_pointer, "FDTPTR" },
38 {},
39 };
40
41 void __init *efi_fdt_pointer(void)
42 {
43 if (!efi_systab)
44 return NULL;
45
46 if (fdt_pointer == EFI_INVALID_TABLE_ADDR)
47 return NULL;
48
49 return early_memremap_ro(fdt_pointer, SZ_64K);
50 }
51
52 void __init efi_runtime_init(void)
53 {
54 if (!efi_enabled(EFI_BOOT) || !efi_systab->runtime)
55 return;
56
57 if (efi_runtime_disabled()) {
58 pr_info("EFI runtime services will be disabled.\n");
59 return;
60 }
61
62 efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
63 efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
64
65 efi_native_runtime_setup();
66 set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
67 }
68
69 bool efi_poweroff_required(void)
70 {
71 return efi_enabled(EFI_RUNTIME_SERVICES) &&
72 (acpi_gbl_reduced_hardware || acpi_no_s5);
73 }
74
75 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
76
77 #if defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON)
78 struct screen_info screen_info __section(".data");
79 EXPORT_SYMBOL_GPL(screen_info);
80 #endif
81
82 static void __init init_screen_info(void)
83 {
84 struct screen_info *si;
85
86 if (screen_info_table == EFI_INVALID_TABLE_ADDR)
87 return;
88
89 si = early_memremap(screen_info_table, sizeof(*si));
90 if (!si) {
91 pr_err("Could not map screen_info config table\n");
92 return;
93 }
94 screen_info = *si;
95 memset(si, 0, sizeof(*si));
96 early_memunmap(si, sizeof(*si));
97
98 memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
99 }
100
101 void __init efi_init(void)
102 {
103 int size;
104 void *config_tables;
105 struct efi_boot_memmap *tbl;
106
107 if (!efi_system_table)
108 return;
109
110 efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
111 if (!efi_systab) {
112 pr_err("Can't find EFI system table.\n");
113 return;
114 }
115
116 efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
117
118 set_bit(EFI_64BIT, &efi.flags);
119 efi_nr_tables = efi_systab->nr_tables;
120 efi_config_table = (unsigned long)efi_systab->tables;
121
122 size = sizeof(efi_config_table_t);
123 config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
124 efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
125 early_memunmap(config_tables, efi_nr_tables * size);
126
127 set_bit(EFI_CONFIG_TABLES, &efi.flags);
128
129 if (IS_ENABLED(CONFIG_EFI_EARLYCON) || IS_ENABLED(CONFIG_SYSFB))
130 init_screen_info();
131
132 if (boot_memmap == EFI_INVALID_TABLE_ADDR)
133 return;
134
135 tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
136 if (tbl) {
137 struct efi_memory_map_data data;
138
139 data.phys_map = boot_memmap + sizeof(*tbl);
140 data.size = tbl->map_size;
141 data.desc_size = tbl->desc_size;
142 data.desc_version = tbl->desc_ver;
143
144 if (efi_memmap_init_early(&data) < 0)
145 panic("Unable to map EFI memory map.\n");
146
147 early_memunmap(tbl, sizeof(*tbl));
148 }
149
150 efi_esrt_init();
151 }
152
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