xref: /openbmc/u-boot/arch/arm/lib/image.c (revision 8ee59472)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2000-2009
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 #include <common.h>
8 #include <mapmem.h>
9 #include <linux/sizes.h>
10 
11 DECLARE_GLOBAL_DATA_PTR;
12 
13 #define LINUX_ARM64_IMAGE_MAGIC 0x644d5241
14 
15 /* See Documentation/arm64/booting.txt in the Linux kernel */
16 struct Image_header {
17 	uint32_t	code0;		/* Executable code */
18 	uint32_t	code1;		/* Executable code */
19 	uint64_t	text_offset;	/* Image load offset, LE */
20 	uint64_t	image_size;	/* Effective Image size, LE */
21 	uint64_t	flags;		/* Kernel flags, LE */
22 	uint64_t	res2;		/* reserved */
23 	uint64_t	res3;		/* reserved */
24 	uint64_t	res4;		/* reserved */
25 	uint32_t	magic;		/* Magic number */
26 	uint32_t	res5;
27 };
28 
29 int booti_setup(ulong image, ulong *relocated_addr, ulong *size)
30 {
31 	struct Image_header *ih;
32 	uint64_t dst;
33 	uint64_t image_size, text_offset;
34 
35 	*relocated_addr = image;
36 
37 	ih = (struct Image_header *)map_sysmem(image, 0);
38 
39 	if (ih->magic != le32_to_cpu(LINUX_ARM64_IMAGE_MAGIC)) {
40 		puts("Bad Linux ARM64 Image magic!\n");
41 		return 1;
42 	}
43 
44 	/*
45 	 * Prior to Linux commit a2c1d73b94ed, the text_offset field
46 	 * is of unknown endianness.  In these cases, the image_size
47 	 * field is zero, and we can assume a fixed value of 0x80000.
48 	 */
49 	if (ih->image_size == 0) {
50 		puts("Image lacks image_size field, assuming 16MiB\n");
51 		image_size = 16 << 20;
52 		text_offset = 0x80000;
53 	} else {
54 		image_size = le64_to_cpu(ih->image_size);
55 		text_offset = le64_to_cpu(ih->text_offset);
56 	}
57 
58 	*size = image_size;
59 
60 	/*
61 	 * If bit 3 of the flags field is set, the 2MB aligned base of the
62 	 * kernel image can be anywhere in physical memory, so respect
63 	 * images->ep.  Otherwise, relocate the image to the base of RAM
64 	 * since memory below it is not accessible via the linear mapping.
65 	 */
66 	if (le64_to_cpu(ih->flags) & BIT(3))
67 		dst = image - text_offset;
68 	else
69 		dst = gd->bd->bi_dram[0].start;
70 
71 	*relocated_addr = ALIGN(dst, SZ_2M) + text_offset;
72 
73 	unmap_sysmem(ih);
74 
75 	return 0;
76 }
77