xref: /openbmc/u-boot/arch/arm/lib/image.c (revision 9d466f2f)
1 /*
2  * (C) Copyright 2000-2009
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier: GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <mapmem.h>
10 #include <linux/sizes.h>
11 
12 DECLARE_GLOBAL_DATA_PTR;
13 
14 #define LINUX_ARM64_IMAGE_MAGIC 0x644d5241
15 
16 /* See Documentation/arm64/booting.txt in the Linux kernel */
17 struct Image_header {
18 	uint32_t	code0;		/* Executable code */
19 	uint32_t	code1;		/* Executable code */
20 	uint64_t	text_offset;	/* Image load offset, LE */
21 	uint64_t	image_size;	/* Effective Image size, LE */
22 	uint64_t	flags;		/* Kernel flags, LE */
23 	uint64_t	res2;		/* reserved */
24 	uint64_t	res3;		/* reserved */
25 	uint64_t	res4;		/* reserved */
26 	uint32_t	magic;		/* Magic number */
27 	uint32_t	res5;
28 };
29 
30 int booti_setup(ulong image, ulong *relocated_addr, ulong *size)
31 {
32 	struct Image_header *ih;
33 	uint64_t dst;
34 	uint64_t image_size, text_offset;
35 
36 	*relocated_addr = image;
37 
38 	ih = (struct Image_header *)map_sysmem(image, 0);
39 
40 	if (ih->magic != le32_to_cpu(LINUX_ARM64_IMAGE_MAGIC)) {
41 		puts("Bad Linux ARM64 Image magic!\n");
42 		return 1;
43 	}
44 
45 	/*
46 	 * Prior to Linux commit a2c1d73b94ed, the text_offset field
47 	 * is of unknown endianness.  In these cases, the image_size
48 	 * field is zero, and we can assume a fixed value of 0x80000.
49 	 */
50 	if (ih->image_size == 0) {
51 		puts("Image lacks image_size field, assuming 16MiB\n");
52 		image_size = 16 << 20;
53 		text_offset = 0x80000;
54 	} else {
55 		image_size = le64_to_cpu(ih->image_size);
56 		text_offset = le64_to_cpu(ih->text_offset);
57 	}
58 
59 	*size = image_size;
60 
61 	/*
62 	 * If bit 3 of the flags field is set, the 2MB aligned base of the
63 	 * kernel image can be anywhere in physical memory, so respect
64 	 * images->ep.  Otherwise, relocate the image to the base of RAM
65 	 * since memory below it is not accessible via the linear mapping.
66 	 */
67 	if (le64_to_cpu(ih->flags) & BIT(3))
68 		dst = image - text_offset;
69 	else
70 		dst = gd->bd->bi_dram[0].start;
71 
72 	*relocated_addr = ALIGN(dst, SZ_2M) + text_offset;
73 
74 	unmap_sysmem(ih);
75 
76 	return 0;
77 }
78