drivers/firmware/efi/libstub/loongarch-stub.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Author: Yun Liu <liuyun@loongson.cn>
 *         Huacai Chen <chenhuacai@loongson.cn>
 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
 */

#include <asm/efi.h>
#include <asm/addrspace.h>
#include "efistub.h"

extern int kernel_asize;
extern int kernel_fsize;
extern int kernel_offset;
extern int kernel_entry;

efi_status_t handle_kernel_image(unsigned long *image_addr,
				 unsigned long *image_size,
				 unsigned long *reserve_addr,
				 unsigned long *reserve_size,
				 efi_loaded_image_t *image,
				 efi_handle_t image_handle)
{
	int nr_pages = round_up(kernel_asize, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
	efi_physical_addr_t kernel_addr = EFI_KIMG_PREFERRED_ADDRESS;
	efi_status_t status;

	/*
	 * Allocate space for the kernel image at the preferred offset. This is
	 * the only location in memory from where we can execute the image, so
	 * no point in falling back to another allocation.
	 */
	status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
			     EFI_LOADER_DATA, nr_pages, &kernel_addr);
	if (status != EFI_SUCCESS)
		return status;

	*image_addr = EFI_KIMG_PREFERRED_ADDRESS;
	*image_size = kernel_asize;

	memcpy((void *)EFI_KIMG_PREFERRED_ADDRESS,
	       (void *)&kernel_offset - kernel_offset,
	       kernel_fsize);

	return status;
}

unsigned long kernel_entry_address(void)
{
	unsigned long base = (unsigned long)&kernel_offset - kernel_offset;

	return (unsigned long)&kernel_entry - base + VMLINUX_LOAD_ADDRESS;
}