arm64: efi: prefer AllocatePages() over efi_low_alloc() for vmlinux

#include <asm/efi.h>

#include <asm/sections.h>

efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table,

efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table_arg,

					unsigned long *image_addr,

					unsigned long *image_size,

					unsigned long *reserve_addr,

{

	efi_status_t status;

	unsigned long kernel_size, kernel_memsize = 0;

	unsigned long nr_pages;

	void *old_image_addr = (void *)*image_addr;

	/* Relocate the image, if required. */

	kernel_size = _edata - _text;

	if (*image_addr != (dram_base + TEXT_OFFSET)) {

		kernel_memsize = kernel_size + (_end - _edata);

		status = efi_low_alloc(sys_table, kernel_memsize + TEXT_OFFSET,

		/*

		 * First, try a straight allocation at the preferred offset.

		 * This will work around the issue where, if dram_base == 0x0,

		 * efi_low_alloc() refuses to allocate at 0x0 (to prevent the

		 * address of the allocation to be mistaken for a FAIL return

		 * value or a NULL pointer). It will also ensure that, on

		 * platforms where the [dram_base, dram_base + TEXT_OFFSET)

		 * interval is partially occupied by the firmware (like on APM

		 * Mustang), we can still place the kernel at the address

		 * 'dram_base + TEXT_OFFSET'.

		 */

		*image_addr = *reserve_addr = dram_base + TEXT_OFFSET;

		nr_pages = round_up(kernel_memsize, EFI_ALLOC_ALIGN) /

			   EFI_PAGE_SIZE;

		status = efi_call_early(allocate_pages, EFI_ALLOCATE_ADDRESS,

					EFI_LOADER_DATA, nr_pages,

					(efi_physical_addr_t *)reserve_addr);

		if (status != EFI_SUCCESS) {

			kernel_memsize += TEXT_OFFSET;

			status = efi_low_alloc(sys_table_arg, kernel_memsize,

					       SZ_2M, reserve_addr);

			if (status != EFI_SUCCESS) {

			pr_efi_err(sys_table, "Failed to relocate kernel\n");

				pr_efi_err(sys_table_arg, "Failed to relocate kernel\n");

				return status;

			}

		memcpy((void *)*reserve_addr + TEXT_OFFSET, (void *)*image_addr,

		       kernel_size);

			*image_addr = *reserve_addr + TEXT_OFFSET;

		*reserve_size = kernel_memsize + TEXT_OFFSET;

		}

		memcpy((void *)*image_addr, old_image_addr, kernel_size);

		*reserve_size = kernel_memsize;

	}