1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
#include <console/console.h>
#include <ip_checksum.h>
#include <boot/elf.h>
#include <boot/elf_boot.h>
#include <string.h>
#include <cpu/x86/multiboot.h>
#ifndef CMD_LINE
#define CMD_LINE ""
#endif
#define UPSZ(X) ((sizeof(X) + 3) &~3)
static struct {
Elf_Bhdr hdr;
Elf_Nhdr ft_hdr;
unsigned char ft_desc[UPSZ(FIRMWARE_TYPE)];
Elf_Nhdr bl_hdr;
unsigned char bl_desc[UPSZ(BOOTLOADER)];
Elf_Nhdr blv_hdr;
unsigned char blv_desc[UPSZ(BOOTLOADER_VERSION)];
Elf_Nhdr cmd_hdr;
unsigned char cmd_desc[UPSZ(CMD_LINE)];
} elf_boot_notes = {
.hdr = {
.b_signature = 0x0E1FB007,
.b_size = sizeof(elf_boot_notes),
.b_checksum = 0,
.b_records = 4,
},
.ft_hdr = {
.n_namesz = 0,
.n_descsz = sizeof(FIRMWARE_TYPE),
.n_type = EBN_FIRMWARE_TYPE,
},
.ft_desc = FIRMWARE_TYPE,
.bl_hdr = {
.n_namesz = 0,
.n_descsz = sizeof(BOOTLOADER),
.n_type = EBN_BOOTLOADER_NAME,
},
.bl_desc = BOOTLOADER,
.blv_hdr = {
.n_namesz = 0,
.n_descsz = sizeof(BOOTLOADER_VERSION),
.n_type = EBN_BOOTLOADER_VERSION,
},
.blv_desc = BOOTLOADER_VERSION,
.cmd_hdr = {
.n_namesz = 0,
.n_descsz = sizeof(CMD_LINE),
.n_type = EBN_COMMAND_LINE,
},
.cmd_desc = CMD_LINE,
};
int elf_check_arch(Elf_ehdr *ehdr)
{
return (
((ehdr->e_machine == EM_386) || (ehdr->e_machine == EM_486)) &&
(ehdr->e_ident[EI_CLASS] == ELFCLASS32) &&
(ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
);
}
void jmp_to_elf_entry(void *entry, unsigned long buffer, unsigned long bounce_size)
{
extern unsigned char _ram_seg, _eram_seg;
unsigned long lb_start, lb_size;
unsigned long adjust, adjusted_boot_notes;
elf_boot_notes.hdr.b_checksum =
compute_ip_checksum(&elf_boot_notes, sizeof(elf_boot_notes));
lb_start = (unsigned long)&_ram_seg;
lb_size = (unsigned long)(&_eram_seg - &_ram_seg);
adjust = buffer + bounce_size - lb_start;
adjusted_boot_notes = (unsigned long)&elf_boot_notes;
adjusted_boot_notes += adjust;
printk_spew("entry = 0x%08lx\n", (unsigned long)entry);
printk_spew("lb_start = 0x%08lx\n", lb_start);
printk_spew("lb_size = 0x%08lx\n", lb_size);
printk_spew("adjust = 0x%08lx\n", adjust);
printk_spew("buffer = 0x%08lx\n", buffer);
printk_spew(" elf_boot_notes = 0x%08lx\n", (unsigned long)&elf_boot_notes);
printk_spew("adjusted_boot_notes = 0x%08lx\n", adjusted_boot_notes);
/* Jump to kernel */
__asm__ __volatile__(
" cld \n\t"
/* Save the callee save registers... */
" pushl %%esi\n\t"
" pushl %%edi\n\t"
" pushl %%ebx\n\t"
/* Save the parameters I was passed */
" pushl $0\n\t" /* 20 adjust */
" pushl %0\n\t" /* 16 lb_start */
" pushl %1\n\t" /* 12 buffer */
" pushl %2\n\t" /* 8 lb_size */
" pushl %3\n\t" /* 4 entry */
" pushl %4\n\t" /* 0 elf_boot_notes */
/* Compute the adjustment */
" xorl %%eax, %%eax\n\t"
" subl 16(%%esp), %%eax\n\t"
" addl 12(%%esp), %%eax\n\t"
" addl 8(%%esp), %%eax\n\t"
" movl %%eax, 20(%%esp)\n\t"
/* Place a copy of coreboot in its new location */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 12(%%esp), %%edi\n\t"
" addl 8(%%esp), %%edi\n\t"
" movl 16(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\n"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Adjust the stack pointer to point into the new coreboot image */
" addl 20(%%esp), %%esp\n\t"
/* Adjust the instruction pointer to point into the new coreboot image */
" movl $1f, %%eax\n\t"
" addl 20(%%esp), %%eax\n\t"
" jmp *%%eax\n\t"
"1: \n\t"
/* Copy the coreboot bounce buffer over coreboot */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 16(%%esp), %%edi\n\t"
" movl 12(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\t"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Now jump to the loaded image */
" movl %5, %%eax\n\t"
" movl 0(%%esp), %%ebx\n\t"
" call *4(%%esp)\n\t"
/* The loaded image returned? */
" cli \n\t"
" cld \n\t"
/* Copy the saved copy of coreboot where coreboot runs */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 16(%%esp), %%edi\n\t"
" movl 12(%%esp), %%esi\n\t"
" addl 8(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\t"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Adjust the stack pointer to point into the old coreboot image */
" subl 20(%%esp), %%esp\n\t"
/* Adjust the instruction pointer to point into the old coreboot image */
" movl $1f, %%eax\n\t"
" subl 20(%%esp), %%eax\n\t"
" jmp *%%eax\n\t"
"1: \n\t"
/* Drop the parameters I was passed */
" addl $24, %%esp\n\t"
/* Restore the callee save registers */
" popl %%ebx\n\t"
" popl %%edi\n\t"
" popl %%esi\n\t"
::
"ri" (lb_start), "ri" (buffer), "ri" (lb_size),
"ri" (entry),
#if CONFIG_MULTIBOOT
"ri"(mbi), "ri" (MB_MAGIC2)
#else
"ri"(adjusted_boot_notes), "ri" (0x0E1FB007)
#endif
);
}
|
