1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2013, 2014 Linaro Ltd;  <roy.franz@linaro.org>
4  *
5  * This file implements the EFI boot stub for the arm64 kernel.
6  * Adapted from ARM version by Mark Salter <msalter@redhat.com>
7  */
8 
9 
10 #include <linux/efi.h>
11 #include <asm/efi.h>
12 #include <asm/memory.h>
13 #include <asm/sections.h>
14 
15 #include "efistub.h"
16 
17 efi_status_t handle_kernel_image(unsigned long *image_addr,
18 				 unsigned long *image_size,
19 				 unsigned long *reserve_addr,
20 				 unsigned long *reserve_size,
21 				 efi_loaded_image_t *image,
22 				 efi_handle_t image_handle)
23 {
24 	efi_status_t status;
25 	unsigned long kernel_size, kernel_codesize, kernel_memsize;
26 
27 	if (image->image_base != _text) {
28 		efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
29 		image->image_base = _text;
30 	}
31 
32 	if (!IS_ALIGNED((u64)_text, SEGMENT_ALIGN))
33 		efi_err("FIRMWARE BUG: kernel image not aligned on %dk boundary\n",
34 			SEGMENT_ALIGN >> 10);
35 
36 	kernel_size = _edata - _text;
37 	kernel_codesize = __inittext_end - _text;
38 	kernel_memsize = kernel_size + (_end - _edata);
39 	*reserve_size = kernel_memsize;
40 	*image_addr = (unsigned long)_text;
41 
42 	status = efi_kaslr_relocate_kernel(image_addr,
43 					   reserve_addr, reserve_size,
44 					   kernel_size, kernel_codesize,
45 					   kernel_memsize,
46 					   efi_kaslr_get_phys_seed(image_handle));
47 	if (status != EFI_SUCCESS)
48 		return status;
49 
50 	return EFI_SUCCESS;
51 }
52 
53 asmlinkage void primary_entry(void);
54 
55 unsigned long primary_entry_offset(void)
56 {
57 	/*
58 	 * When built as part of the kernel, the EFI stub cannot branch to the
59 	 * kernel proper via the image header, as the PE/COFF header is
60 	 * strictly not part of the in-memory presentation of the image, only
61 	 * of the file representation. So instead, we need to jump to the
62 	 * actual entrypoint in the .text region of the image.
63 	 */
64 	return (char *)primary_entry - _text;
65 }
66 
67 void efi_icache_sync(unsigned long start, unsigned long end)
68 {
69 	caches_clean_inval_pou(start, end);
70 }
71