xref: /rk3399_rockchip-uboot/arch/x86/lib/relocate.c (revision b156ff09aad5a54b5a47b940ebc26aeeae56ee07)
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  * See file CREDITS for list of people who contributed to this
16  * project.
17  *
18  * This program is free software; you can redistribute it and/or
19  * modify it under the terms of the GNU General Public License as
20  * published by the Free Software Foundation; either version 2 of
21  * the License, or (at your option) any later version.
22  *
23  * This program is distributed in the hope that it will be useful,
24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
26  * GNU General Public License for more details.
27  *
28  * You should have received a copy of the GNU General Public License
29  * along with this program; if not, write to the Free Software
30  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
31  * MA 02111-1307 USA
32  */
33 
34 #include <common.h>
35 #include <malloc.h>
36 #include <asm/u-boot-x86.h>
37 #include <elf.h>
38 
39 static int copy_uboot_to_ram(void);
40 static int clear_bss(void);
41 static int do_elf_reloc_fixups(void);
42 
43 static int copy_uboot_to_ram(void)
44 {
45 	size_t len = (size_t)&__data_end - (size_t)&__text_start;
46 
47 	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);
48 
49 	return 0;
50 }
51 
52 static int clear_bss(void)
53 {
54 	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
55 	size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
56 
57 	memset((void *)dst_addr, 0x00, len);
58 
59 	return 0;
60 }
61 
62 static int do_elf_reloc_fixups(void)
63 {
64 	Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start);
65 	Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end);
66 
67 	Elf32_Addr *offset_ptr_rom;
68 	Elf32_Addr *offset_ptr_ram;
69 
70 	/* The size of the region of u-boot that runs out of RAM. */
71 	uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start;
72 
73 	do {
74 		/* Get the location from the relocation entry */
75 		offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
76 
77 		/* Check that the location of the relocation is in .text */
78 		if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE) {
79 
80 			/* Switch to the in-RAM version */
81 			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
82 							gd->reloc_off);
83 
84 			/* Check that the target points into .text */
85 			if (*offset_ptr_ram >= CONFIG_SYS_TEXT_BASE &&
86 					*offset_ptr_ram <
87 					(CONFIG_SYS_TEXT_BASE + size)) {
88 				*offset_ptr_ram += gd->reloc_off;
89 			}
90 		}
91 	} while (re_src++ < re_end);
92 
93 	return 0;
94 }
95 
96 void relocate_code(ulong dummy_1, gd_t *id, ulong dummy_2)
97 {
98 	/*
99 	 * Copy U-Boot into RAM, clear the BSS and perform relocation
100 	 * adjustments
101 	 */
102 	copy_uboot_to_ram();
103 	clear_bss();
104 	do_elf_reloc_fixups();
105 
106 	/*
107 	 * Transfer execution from Flash to RAM by calculating the address
108 	 * of the in-RAM copy of board_init_r() and calling it
109 	 */
110 	(board_init_r + gd->reloc_off)(gd, gd->relocaddr);
111 
112 	/* NOTREACHED - board_init_r() does not return */
113 	while (1)
114 		;
115 }
116