xref: /openbmc/u-boot/arch/x86/lib/relocate.c (revision 0d9edd2d)
1 /*
2  * (C) Copyright 2008-2011
3  * Graeme Russ, <graeme.russ@gmail.com>
4  *
5  * (C) Copyright 2002
6  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
7  *
8  * (C) Copyright 2002
9  * Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
10  *
11  * (C) Copyright 2002
12  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
13  * Marius Groeger <mgroeger@sysgo.de>
14  *
15  * SPDX-License-Identifier:	GPL-2.0+
16  */
17 
18 #include <common.h>
19 #include <inttypes.h>
20 #include <asm/u-boot-x86.h>
21 #include <asm/relocate.h>
22 #include <asm/sections.h>
23 #include <elf.h>
24 
25 DECLARE_GLOBAL_DATA_PTR;
26 
27 int copy_uboot_to_ram(void)
28 {
29 	size_t len = (size_t)&__data_end - (size_t)&__text_start;
30 
31 	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);
32 
33 	return 0;
34 }
35 
36 int clear_bss(void)
37 {
38 	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
39 	size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
40 
41 	memset((void *)dst_addr, 0x00, len);
42 
43 	return 0;
44 }
45 
46 /*
47  * This function has more error checking than you might expect. Please see
48  * the commit message for more informaiton.
49  */
50 int do_elf_reloc_fixups(void)
51 {
52 	Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start);
53 	Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end);
54 
55 	Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
56 	Elf32_Addr *offset_ptr_ram;
57 
58 	/* The size of the region of u-boot that runs out of RAM. */
59 	uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start;
60 
61 	if (re_src == re_end)
62 		panic("No relocation data");
63 
64 	do {
65 		/* Get the location from the relocation entry */
66 		offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
67 
68 		/* Check that the location of the relocation is in .text */
69 		if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE &&
70 				offset_ptr_rom > last_offset) {
71 
72 			/* Switch to the in-RAM version */
73 			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
74 							gd->reloc_off);
75 
76 			/* Check that the target points into .text */
77 			if (*offset_ptr_ram >= CONFIG_SYS_TEXT_BASE &&
78 					*offset_ptr_ram <=
79 					(CONFIG_SYS_TEXT_BASE + size)) {
80 				*offset_ptr_ram += gd->reloc_off;
81 			} else {
82 				debug("   %p: rom reloc %x, ram %p, value %x,"
83 					" limit %" PRIXPTR "\n", re_src,
84 					re_src->r_offset, offset_ptr_ram,
85 					*offset_ptr_ram,
86 					CONFIG_SYS_TEXT_BASE + size);
87 			}
88 		} else {
89 			debug("   %p: rom reloc %x, last %p\n", re_src,
90 			       re_src->r_offset, last_offset);
91 		}
92 		last_offset = offset_ptr_rom;
93 
94 	} while (++re_src < re_end);
95 
96 	return 0;
97 }
98