1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2008-2011
4  * Graeme Russ, <graeme.russ@gmail.com>
5  *
6  * (C) Copyright 2002
7  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
8  *
9  * (C) Copyright 2002
10  * Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
11  *
12  * (C) Copyright 2002
13  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
14  * Marius Groeger <mgroeger@sysgo.de>
15  */
16 
17 #include <common.h>
18 #include <log.h>
19 #include <relocate.h>
20 #include <asm/global_data.h>
21 #include <asm/u-boot-x86.h>
22 #include <asm/sections.h>
23 #include <elf.h>
24 
25 DECLARE_GLOBAL_DATA_PTR;
26 
copy_uboot_to_ram(void)27 int copy_uboot_to_ram(void)
28 {
29 	size_t len = (uintptr_t)&__data_end - (uintptr_t)&__text_start;
30 
31 	if (gd->flags & GD_FLG_SKIP_RELOC)
32 		return 0;
33 	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);
34 
35 	return 0;
36 }
37 
38 #ifndef CONFIG_EFI_APP
clear_bss(void)39 int clear_bss(void)
40 {
41 	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
42 	size_t len = (uintptr_t)&__bss_end - (uintptr_t)&__bss_start;
43 
44 	if (gd->flags & GD_FLG_SKIP_RELOC)
45 		return 0;
46 	memset((void *)dst_addr, 0x00, len);
47 
48 	return 0;
49 }
50 #endif
51 
52 #if CONFIG_IS_ENABLED(X86_64)
do_elf_reloc_fixups64(unsigned int text_base,uintptr_t size,Elf64_Rela * re_src,Elf64_Rela * re_end)53 static void do_elf_reloc_fixups64(unsigned int text_base, uintptr_t size,
54 				  Elf64_Rela *re_src, Elf64_Rela *re_end)
55 {
56 	Elf64_Addr *offset_ptr_rom, *last_offset = NULL;
57 	Elf64_Addr *offset_ptr_ram;
58 
59 	do {
60 		unsigned long long type = ELF64_R_TYPE(re_src->r_info);
61 
62 		if (type != R_X86_64_RELATIVE) {
63 			printf("%s: unsupported relocation type 0x%llx "
64 			       "at %p, ", __func__, type, re_src);
65 			printf("offset = 0x%llx\n", re_src->r_offset);
66 			continue;
67 		}
68 
69 		/* Get the location from the relocation entry */
70 		offset_ptr_rom = (Elf64_Addr *)(uintptr_t)re_src->r_offset;
71 
72 		/* Check that the location of the relocation is in .text */
73 		if (offset_ptr_rom >= (Elf64_Addr *)(uintptr_t)text_base &&
74 		    offset_ptr_rom > last_offset) {
75 			/* Switch to the in-RAM version */
76 			offset_ptr_ram = (Elf64_Addr *)((ulong)offset_ptr_rom +
77 							gd->reloc_off);
78 
79 			/* Check that the target points into .text */
80 			if (*offset_ptr_ram >= text_base &&
81 			    *offset_ptr_ram <= text_base + size) {
82 				*offset_ptr_ram = gd->reloc_off +
83 							re_src->r_addend;
84 			} else {
85 				debug("   %p: %lx: rom reloc %lx, ram %p, value %lx, limit %lX\n",
86 				      re_src, (ulong)re_src->r_info,
87 				      (ulong)re_src->r_offset, offset_ptr_ram,
88 				      (ulong)*offset_ptr_ram, text_base + size);
89 			}
90 		} else {
91 			debug("   %p: %lx: rom reloc %lx, last %p\n", re_src,
92 			      (ulong)re_src->r_info, (ulong)re_src->r_offset,
93 			      last_offset);
94 		}
95 		last_offset = offset_ptr_rom;
96 
97 	} while (++re_src < re_end);
98 }
99 #else
do_elf_reloc_fixups32(unsigned int text_base,uintptr_t size,Elf32_Rel * re_src,Elf32_Rel * re_end)100 static void do_elf_reloc_fixups32(unsigned int text_base, uintptr_t size,
101 				  Elf32_Rel *re_src, Elf32_Rel *re_end)
102 {
103 	Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
104 	Elf32_Addr *offset_ptr_ram;
105 
106 	do {
107 		unsigned int type = ELF32_R_TYPE(re_src->r_info);
108 
109 		if (type != R_386_RELATIVE) {
110 			printf("%s: unsupported relocation type 0x%x "
111 			       "at %p, ", __func__, type, re_src);
112 			printf("offset = 0x%x\n", re_src->r_offset);
113 			continue;
114 		}
115 
116 		/* Get the location from the relocation entry */
117 		offset_ptr_rom = (Elf32_Addr *)(uintptr_t)re_src->r_offset;
118 
119 		/* Check that the location of the relocation is in .text */
120 		if (offset_ptr_rom >= (Elf32_Addr *)(uintptr_t)text_base &&
121 		    offset_ptr_rom > last_offset) {
122 
123 			/* Switch to the in-RAM version */
124 			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
125 							gd->reloc_off);
126 
127 			/* Check that the target points into .text */
128 			if (*offset_ptr_ram >= text_base &&
129 			    *offset_ptr_ram <= text_base + size) {
130 				*offset_ptr_ram += gd->reloc_off;
131 			} else {
132 				debug("   %p: rom reloc %x, ram %p, value %x, limit %lX\n",
133 				      re_src, re_src->r_offset, offset_ptr_ram,
134 				      *offset_ptr_ram, text_base + size);
135 			}
136 		} else {
137 			debug("   %p: rom reloc %x, last %p\n", re_src,
138 			       re_src->r_offset, last_offset);
139 		}
140 		last_offset = offset_ptr_rom;
141 
142 	} while (++re_src < re_end);
143 }
144 #endif
145 
146 /*
147  * This function has more error checking than you might expect. Please see
148  * this commit message for more information:
149  *    62f7970a x86: Add error checking to x86 relocation code
150  */
do_elf_reloc_fixups(void)151 int do_elf_reloc_fixups(void)
152 {
153 	void *re_src = (void *)(&__rel_dyn_start);
154 	void *re_end = (void *)(&__rel_dyn_end);
155 	uint text_base;
156 
157 	/* The size of the region of u-boot that runs out of RAM. */
158 	uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start;
159 
160 	if (gd->flags & GD_FLG_SKIP_RELOC)
161 		return 0;
162 	if (re_src == re_end)
163 		panic("No relocation data");
164 
165 #ifdef CONFIG_TEXT_BASE
166 	text_base = CONFIG_TEXT_BASE;
167 #else
168 	panic("No CONFIG_TEXT_BASE");
169 #endif
170 #if CONFIG_IS_ENABLED(X86_64)
171 	do_elf_reloc_fixups64(text_base, size, re_src, re_end);
172 #else
173 	do_elf_reloc_fixups32(text_base, size, re_src, re_end);
174 #endif
175 
176 	return 0;
177 }
178