2010-01-09 23:30:33 +00:00
|
|
|
/*
|
|
|
|
* GRUB -- GRand Unified Bootloader
|
|
|
|
* Copyright (C) 2009,2010 Free Software Foundation, Inc.
|
|
|
|
*
|
|
|
|
* GRUB is free software: you can redistribute it and/or modify
|
|
|
|
* it under the terms of the GNU General Public License as published by
|
|
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
|
|
* (at your option) any later version.
|
|
|
|
*
|
|
|
|
* GRUB is distributed in the hope that it will be useful,
|
|
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
* GNU General Public License for more details.
|
|
|
|
*
|
|
|
|
* You should have received a copy of the GNU General Public License
|
|
|
|
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <grub/symbol.h>
|
|
|
|
#include <grub/i386/memory.h>
|
|
|
|
|
|
|
|
#ifdef __x86_64__
|
|
|
|
#define RAX %rax
|
2010-01-12 22:30:52 +00:00
|
|
|
#define RSI %rsi
|
2010-01-09 23:30:33 +00:00
|
|
|
#else
|
|
|
|
#define RAX %eax
|
|
|
|
#define RSI %esi
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* The code segment of the protected mode. */
|
|
|
|
#define CODE_SEGMENT 0x10
|
|
|
|
|
|
|
|
/* The data segment of the protected mode. */
|
|
|
|
#define DATA_SEGMENT 0x18
|
|
|
|
|
|
|
|
.p2align 4 /* force 16-byte alignment */
|
|
|
|
|
|
|
|
VARIABLE(grub_relocator32_start)
|
|
|
|
LOCAL(base):
|
|
|
|
/* %rax contains now our new 'base'. */
|
|
|
|
mov RAX, RSI
|
|
|
|
add $(LOCAL(cont0) - LOCAL(base)), RAX
|
|
|
|
jmp *RAX
|
|
|
|
LOCAL(cont0):
|
|
|
|
lea (LOCAL(cont1) - LOCAL(base)) (RSI, 1), RAX
|
|
|
|
movl %eax, (LOCAL(jump_vector) - LOCAL(base)) (RSI, 1)
|
|
|
|
|
|
|
|
lea (LOCAL(gdt) - LOCAL(base)) (RSI, 1), RAX
|
|
|
|
mov RAX, (LOCAL(gdt_addr) - LOCAL(base)) (RSI, 1)
|
|
|
|
|
|
|
|
/* Switch to compatibility mode. */
|
|
|
|
|
|
|
|
lgdt (LOCAL(gdtdesc) - LOCAL(base)) (RSI, 1)
|
|
|
|
|
|
|
|
/* Update %cs. */
|
|
|
|
ljmp *(LOCAL(jump_vector) - LOCAL(base)) (RSI, 1)
|
|
|
|
|
|
|
|
LOCAL(cont1):
|
|
|
|
.code32
|
|
|
|
|
|
|
|
/* Update other registers. */
|
|
|
|
movl $DATA_SEGMENT, %eax
|
|
|
|
movl %eax, %ds
|
|
|
|
movl %eax, %es
|
|
|
|
movl %eax, %fs
|
|
|
|
movl %eax, %gs
|
|
|
|
movl %eax, %ss
|
|
|
|
|
|
|
|
/* Disable paging. */
|
|
|
|
movl %cr0, %eax
|
|
|
|
andl $(~GRUB_MEMORY_CPU_CR0_PAGING_ON), %eax
|
|
|
|
movl %eax, %cr0
|
|
|
|
|
|
|
|
/* Disable amd64. */
|
|
|
|
movl $GRUB_MEMORY_CPU_AMD64_MSR, %ecx
|
|
|
|
rdmsr
|
|
|
|
andl $(~GRUB_MEMORY_CPU_AMD64_MSR_ON), %eax
|
|
|
|
wrmsr
|
|
|
|
|
|
|
|
/* Turn off PAE. */
|
|
|
|
movl %cr4, %eax
|
2010-01-12 16:46:17 +00:00
|
|
|
andl $(~GRUB_MEMORY_CPU_CR4_PAE_ON), %eax
|
2010-01-09 23:30:33 +00:00
|
|
|
movl %eax, %cr4
|
|
|
|
|
|
|
|
jmp LOCAL(cont2)
|
|
|
|
LOCAL(cont2):
|
|
|
|
.code32
|
|
|
|
|
|
|
|
/* mov imm32, %eax */
|
|
|
|
.byte 0xb8
|
|
|
|
VARIABLE(grub_relocator32_esp)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
movl %eax, %esp
|
|
|
|
|
2010-01-11 13:59:01 +00:00
|
|
|
/* mov imm32, %eax */
|
|
|
|
.byte 0xb8
|
|
|
|
VARIABLE(grub_relocator32_esi)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
movl %eax, %esi
|
|
|
|
|
2010-01-09 23:30:33 +00:00
|
|
|
/* mov imm32, %eax */
|
|
|
|
.byte 0xb8
|
|
|
|
VARIABLE(grub_relocator32_eax)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
/* mov imm32, %ebx */
|
|
|
|
.byte 0xbb
|
|
|
|
VARIABLE(grub_relocator32_ebx)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
/* mov imm32, %ecx */
|
|
|
|
.byte 0xb9
|
|
|
|
VARIABLE(grub_relocator32_ecx)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
/* mov imm32, %edx */
|
|
|
|
.byte 0xba
|
|
|
|
VARIABLE(grub_relocator32_edx)
|
|
|
|
.long 0
|
|
|
|
|
|
|
|
/* Cleared direction flag is of no problem with any current
|
|
|
|
payload and makes this implementation easier. */
|
|
|
|
cld
|
|
|
|
|
|
|
|
.byte 0xea
|
|
|
|
VARIABLE(grub_relocator32_eip)
|
|
|
|
.long 0
|
|
|
|
.word CODE_SEGMENT
|
|
|
|
|
|
|
|
/* GDT. Copied from loader/i386/linux.c. */
|
|
|
|
.p2align 4
|
|
|
|
LOCAL(gdt):
|
|
|
|
/* NULL. */
|
|
|
|
.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
|
|
|
|
|
|
|
|
/* Reserved. */
|
|
|
|
.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
|
|
|
|
|
|
|
|
/* Code segment. */
|
|
|
|
.byte 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x9A, 0xCF, 0x00
|
|
|
|
|
|
|
|
/* Data segment. */
|
|
|
|
.byte 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x92, 0xCF, 0x00
|
|
|
|
|
|
|
|
.p2align 4
|
|
|
|
LOCAL(gdtdesc):
|
|
|
|
.word 0x27
|
|
|
|
LOCAL(gdt_addr):
|
|
|
|
#ifdef __x86_64__
|
|
|
|
/* Filled by the code. */
|
|
|
|
.quad 0
|
|
|
|
#else
|
|
|
|
/* Filled by the code. */
|
|
|
|
.long 0
|
|
|
|
#endif
|
|
|
|
|
|
|
|
.p2align 4
|
|
|
|
LOCAL(jump_vector):
|
|
|
|
/* Jump location. Is filled by the code */
|
|
|
|
.long 0
|
|
|
|
.long CODE_SEGMENT
|
|
|
|
|
|
|
|
VARIABLE(grub_relocator32_end)
|