xref: /openbmc/u-boot/arch/arm/lib/image.c (revision 8639e34d)
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