xref: /linux/arch/loongarch/kernel/efi.c (revision 84e85359f4999a439aa12e04bf0ae9e13e00fc66)
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/uaccess.h>
22 
23 #include <asm/early_ioremap.h>
24 #include <asm/efi.h>
25 #include <asm/loongson.h>
26 
27 static unsigned long efi_nr_tables;
28 static unsigned long efi_config_table;
29 
30 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
31 
32 static efi_system_table_t *efi_systab;
33 static efi_config_table_type_t arch_tables[] __initdata = {
34 	{LINUX_EFI_BOOT_MEMMAP_GUID,	&boot_memmap,	"MEMMAP" },
35 	{},
36 };
37 
38 void __init efi_runtime_init(void)
39 {
40 	if (!efi_enabled(EFI_BOOT))
41 		return;
42 
43 	if (efi_runtime_disabled()) {
44 		pr_info("EFI runtime services will be disabled.\n");
45 		return;
46 	}
47 
48 	efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
49 	efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
50 
51 	efi_native_runtime_setup();
52 	set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
53 }
54 
55 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
56 
57 static void __init init_screen_info(void)
58 {
59 	struct screen_info *si;
60 
61 	if (screen_info_table == EFI_INVALID_TABLE_ADDR)
62 		return;
63 
64 	si = early_memremap(screen_info_table, sizeof(*si));
65 	if (!si) {
66 		pr_err("Could not map screen_info config table\n");
67 		return;
68 	}
69 	screen_info = *si;
70 	memset(si, 0, sizeof(*si));
71 	early_memunmap(si, sizeof(*si));
72 
73 	memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
74 }
75 
76 void __init efi_init(void)
77 {
78 	int size;
79 	void *config_tables;
80 	struct efi_boot_memmap *tbl;
81 
82 	if (!efi_system_table)
83 		return;
84 
85 	efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
86 	if (!efi_systab) {
87 		pr_err("Can't find EFI system table.\n");
88 		return;
89 	}
90 
91 	efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
92 
93 	set_bit(EFI_64BIT, &efi.flags);
94 	efi_nr_tables	 = efi_systab->nr_tables;
95 	efi_config_table = (unsigned long)efi_systab->tables;
96 
97 	size = sizeof(efi_config_table_t);
98 	config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
99 	efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
100 	early_memunmap(config_tables, efi_nr_tables * size);
101 
102 	set_bit(EFI_CONFIG_TABLES, &efi.flags);
103 
104 	init_screen_info();
105 
106 	if (boot_memmap == EFI_INVALID_TABLE_ADDR)
107 		return;
108 
109 	tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
110 	if (tbl) {
111 		struct efi_memory_map_data data;
112 
113 		data.phys_map		= boot_memmap + sizeof(*tbl);
114 		data.size		= tbl->map_size;
115 		data.desc_size		= tbl->desc_size;
116 		data.desc_version	= tbl->desc_ver;
117 
118 		if (efi_memmap_init_early(&data) < 0)
119 			panic("Unable to map EFI memory map.\n");
120 
121 		early_memunmap(tbl, sizeof(*tbl));
122 	}
123 }
124