xref: /openbmc/linux/arch/loongarch/kernel/efi.c (revision 4b7444ff)
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 efi_system_table_t *efi_systab;
31 static efi_config_table_type_t arch_tables[] __initdata = {{},};
32 
33 void __init efi_runtime_init(void)
34 {
35 	if (!efi_enabled(EFI_BOOT))
36 		return;
37 
38 	if (efi_runtime_disabled()) {
39 		pr_info("EFI runtime services will be disabled.\n");
40 		return;
41 	}
42 
43 	efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
44 	efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
45 
46 	efi_native_runtime_setup();
47 	set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
48 }
49 
50 void __init efi_init(void)
51 {
52 	int size;
53 	void *config_tables;
54 
55 	if (!efi_system_table)
56 		return;
57 
58 	efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
59 	if (!efi_systab) {
60 		pr_err("Can't find EFI system table.\n");
61 		return;
62 	}
63 
64 	set_bit(EFI_64BIT, &efi.flags);
65 	efi_nr_tables	 = efi_systab->nr_tables;
66 	efi_config_table = (unsigned long)efi_systab->tables;
67 
68 	size = sizeof(efi_config_table_t);
69 	config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
70 	efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
71 	early_memunmap(config_tables, efi_nr_tables * size);
72 }
73