xref: /openbmc/u-boot/arch/x86/lib/relocate.c (revision 0b304a24)
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 <libfdt.h>
20 #include <malloc.h>
21 #include <asm/u-boot-x86.h>
22 #include <asm/relocate.h>
23 #include <asm/sections.h>
24 #include <elf.h>
25 
26 DECLARE_GLOBAL_DATA_PTR;
27 
28 int copy_uboot_to_ram(void)
29 {
30 	size_t len = (size_t)&__data_end - (size_t)&__text_start;
31 
32 	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);
33 
34 	return 0;
35 }
36 
37 int copy_fdt_to_ram(void)
38 {
39 	if (gd->new_fdt) {
40 		ulong fdt_size;
41 
42 		fdt_size = ALIGN(fdt_totalsize(gd->fdt_blob) + 0x1000, 32);
43 
44 		memcpy(gd->new_fdt, gd->fdt_blob, fdt_size);
45 		debug("Relocated fdt from %p to %p, size %lx\n",
46 		       gd->fdt_blob, gd->new_fdt, fdt_size);
47 		gd->fdt_blob = gd->new_fdt;
48 	}
49 
50 	return 0;
51 }
52 
53 int clear_bss(void)
54 {
55 	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
56 	size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
57 
58 	memset((void *)dst_addr, 0x00, len);
59 
60 	return 0;
61 }
62 
63 /*
64  * This function has more error checking than you might expect. Please see
65  * the commit message for more informaiton.
66  */
67 int do_elf_reloc_fixups(void)
68 {
69 	Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start);
70 	Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end);
71 
72 	Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
73 	Elf32_Addr *offset_ptr_ram;
74 
75 	/* The size of the region of u-boot that runs out of RAM. */
76 	uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start;
77 
78 	do {
79 		/* Get the location from the relocation entry */
80 		offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
81 
82 		/* Check that the location of the relocation is in .text */
83 		if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE &&
84 				offset_ptr_rom > last_offset) {
85 
86 			/* Switch to the in-RAM version */
87 			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
88 							gd->reloc_off);
89 
90 			/* Check that the target points into .text */
91 			if (*offset_ptr_ram >= CONFIG_SYS_TEXT_BASE &&
92 					*offset_ptr_ram <=
93 					(CONFIG_SYS_TEXT_BASE + size)) {
94 				*offset_ptr_ram += gd->reloc_off;
95 			} else {
96 				debug("   %p: rom reloc %x, ram %p, value %x,"
97 					" limit %lx\n", re_src,
98 					re_src->r_offset, offset_ptr_ram,
99 					*offset_ptr_ram,
100 					CONFIG_SYS_TEXT_BASE + size);
101 			}
102 		} else {
103 			debug("   %p: rom reloc %x, last %p\n", re_src,
104 			       re_src->r_offset, last_offset);
105 		}
106 		last_offset = offset_ptr_rom;
107 
108 	} while (++re_src < re_end);
109 
110 	return 0;
111 }
112