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#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 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 + 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
);
}
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