linux/arch/loongarch/kernel/efi.c
Huacai Chen 628c3bb40e LoongArch: Add boot and setup routines
Add basic boot, setup and reset routines for LoongArch. Now, LoongArch
machines use UEFI-based firmware. The firmware passes configuration
information to the kernel via ACPI and DMI/SMBIOS.

Currently an existing interface between the kernel and the bootloader
is implemented. Kernel gets 2 values from the bootloader, passed in
registers a0 and a1; a0 is an "EFI boot flag" distinguishing UEFI and
non-UEFI firmware, while a1 is a pointer to an FDT with systable,
memmap, cmdline and initrd information.

The standard UEFI boot protocol (EFISTUB) will be added later.

Cc: linux-efi@vger.kernel.org
Cc: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Co-developed-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-06-03 20:09:28 +08:00

73 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* EFI initialization
*
* Author: Jianmin Lv <lvjianmin@loongson.cn>
* Huacai Chen <chenhuacai@loongson.cn>
*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/acpi.h>
#include <linux/efi.h>
#include <linux/efi-bgrt.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/io.h>
#include <linux/kobject.h>
#include <linux/memblock.h>
#include <linux/reboot.h>
#include <linux/uaccess.h>
#include <asm/early_ioremap.h>
#include <asm/efi.h>
#include <asm/loongson.h>
static unsigned long efi_nr_tables;
static unsigned long efi_config_table;
static efi_system_table_t *efi_systab;
static efi_config_table_type_t arch_tables[] __initdata = {{},};
void __init efi_runtime_init(void)
{
if (!efi_enabled(EFI_BOOT))
return;
if (efi_runtime_disabled()) {
pr_info("EFI runtime services will be disabled.\n");
return;
}
efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
efi_native_runtime_setup();
set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
}
void __init efi_init(void)
{
int size;
void *config_tables;
if (!efi_system_table)
return;
efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
if (!efi_systab) {
pr_err("Can't find EFI system table.\n");
return;
}
set_bit(EFI_64BIT, &efi.flags);
efi_nr_tables = efi_systab->nr_tables;
efi_config_table = (unsigned long)efi_systab->tables;
size = sizeof(efi_config_table_t);
config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
early_memunmap(config_tables, efi_nr_tables * size);
}