xref: /openbmc/u-boot/arch/x86/lib/relocate.c (revision b97cd681)
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 <libfdt.h>
21 #include <malloc.h>
22 #include <asm/u-boot-x86.h>
23 #include <asm/relocate.h>
24 #include <asm/sections.h>
25 #include <elf.h>
26 
27 DECLARE_GLOBAL_DATA_PTR;
28 
29 int copy_uboot_to_ram(void)
30 {
31 	size_t len = (size_t)&__data_end - (size_t)&__text_start;
32 
33 	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);
34 
35 	return 0;
36 }
37 
38 int copy_fdt_to_ram(void)
39 {
40 	if (gd->new_fdt) {
41 		ulong fdt_size;
42 
43 		fdt_size = ALIGN(fdt_totalsize(gd->fdt_blob) + 0x1000, 32);
44 
45 		memcpy(gd->new_fdt, gd->fdt_blob, fdt_size);
46 		debug("Relocated fdt from %p to %p, size %lx\n",
47 		       gd->fdt_blob, gd->new_fdt, fdt_size);
48 		gd->fdt_blob = gd->new_fdt;
49 	}
50 
51 	return 0;
52 }
53 
54 int clear_bss(void)
55 {
56 	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
57 	size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
58 
59 	memset((void *)dst_addr, 0x00, len);
60 
61 	return 0;
62 }
63 
64 /*
65  * This function has more error checking than you might expect. Please see
66  * the commit message for more informaiton.
67  */
68 int do_elf_reloc_fixups(void)
69 {
70 	Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start);
71 	Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end);
72 
73 	Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
74 	Elf32_Addr *offset_ptr_ram;
75 
76 	/* The size of the region of u-boot that runs out of RAM. */
77 	uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start;
78 
79 	do {
80 		/* Get the location from the relocation entry */
81 		offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
82 
83 		/* Check that the location of the relocation is in .text */
84 		if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE &&
85 				offset_ptr_rom > last_offset) {
86 
87 			/* Switch to the in-RAM version */
88 			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
89 							gd->reloc_off);
90 
91 			/* Check that the target points into .text */
92 			if (*offset_ptr_ram >= CONFIG_SYS_TEXT_BASE &&
93 					*offset_ptr_ram <=
94 					(CONFIG_SYS_TEXT_BASE + size)) {
95 				*offset_ptr_ram += gd->reloc_off;
96 			} else {
97 				debug("   %p: rom reloc %x, ram %p, value %x,"
98 					" limit %" PRIXPTR "\n", re_src,
99 					re_src->r_offset, offset_ptr_ram,
100 					*offset_ptr_ram,
101 					CONFIG_SYS_TEXT_BASE + size);
102 			}
103 		} else {
104 			debug("   %p: rom reloc %x, last %p\n", re_src,
105 			       re_src->r_offset, last_offset);
106 		}
107 		last_offset = offset_ptr_rom;
108 
109 	} while (++re_src < re_end);
110 
111 	return 0;
112 }
113