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/*
* 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/>.
*/
#define CODE32_SEGMENT 0x18
#define CODE_SEGMENT 0x08
/* The data segment of the protected mode. */
#define DATA_SEGMENT 0x10
#include "relocator_common.S"
.p2align 4 /* force 16-byte alignment */
VARIABLE(grub_relocator64_start)
PREAMBLE
#ifndef __x86_64__
DISABLE_PAGING
/* Turn on PAE. */
movl %cr4, %eax
orl $(GRUB_MEMORY_CPU_CR4_PAE_ON | GRUB_MEMORY_CPU_CR4_PSE_ON), %eax
movl %eax, %cr4
/* mov imm32, %eax */
.byte 0xb8
VARIABLE(grub_relocator64_cr3)
.long 0
movl %eax, %cr3
/* Turn on amd64. */
movl $GRUB_MEMORY_CPU_AMD64_MSR, %ecx
rdmsr
orl $GRUB_MEMORY_CPU_AMD64_MSR_ON, %eax
wrmsr
/* Enable paging. */
movl %cr0, %eax
orl $GRUB_MEMORY_CPU_CR0_PAGING_ON, %eax
movl %eax, %cr0
RELOAD_GDT
#else
/* mov imm64, %rax */
.byte 0x48
.byte 0xb8
VARIABLE(grub_relocator64_cr3)
.quad 0
movq %rax, %cr3
#endif
#ifdef __x86_64__
.code64
#endif
/* mov imm64, %rax */
.byte 0x48
.byte 0xb8
VARIABLE(grub_relocator64_rsp)
.quad 0
#ifdef __x86_64__
movq %rax, %rsp
#else
/* movq %rax, %rsp */
.byte 0x48
.byte 0x89
.byte 0xc4
#endif
#ifdef GRUB_MACHINE_EFI
jmp LOCAL(skip_efi_stack_align)
/*
* Here is grub_relocator64_efi_start() entry point. Most of the
* code below is shared between grub_relocator64_efi_start()
* and grub_relocator64_start().
*
* Think twice before changing anything there!!!
*/
VARIABLE(grub_relocator64_efi_start)
/* Align the stack as UEFI spec requires. */
#ifdef __x86_64__
andq $~15, %rsp
#else
/* andq $~15, %rsp */
.byte 0x48
.byte 0x83
.byte 0xe4
.byte 0xf0
#endif
LOCAL(skip_efi_stack_align):
#endif
/* mov imm64, %rax */
.byte 0x48
.byte 0xb8
VARIABLE(grub_relocator64_rsi)
.quad 0
#ifdef __x86_64__
movq %rax, %rsi
#else
/* movq %rax, %rsi */
.byte 0x48
.byte 0x89
.byte 0xc6
#endif
/* mov imm64, %rax */
.byte 0x48
.byte 0xb8
VARIABLE(grub_relocator64_rax)
.quad 0
/* mov imm64, %rbx */
.byte 0x48
.byte 0xbb
VARIABLE(grub_relocator64_rbx)
.quad 0
/* mov imm64, %rcx */
.byte 0x48
.byte 0xb9
VARIABLE(grub_relocator64_rcx)
.quad 0
/* mov imm64, %rdx */
.byte 0x48
.byte 0xba
VARIABLE(grub_relocator64_rdx)
.quad 0
/* Cleared direction flag is of no problem with any current
payload and makes this implementation easier. */
cld
#if defined (__APPLE__) || !defined (__x86_64__)
.byte 0xff, 0x25
.quad 0
#else
jmp *LOCAL(jump_addr) (%rip)
#endif
LOCAL(jump_addr):
VARIABLE(grub_relocator64_rip)
.quad 0
#ifdef GRUB_MACHINE_EFI
/* Here grub_relocator64_efi_start() ends. Ufff... */
VARIABLE(grub_relocator64_efi_end)
#endif
#ifndef __x86_64__
.p2align 4
LOCAL(gdt):
/* NULL. */
.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
/* 64-bit segment. */
.word 0xffff /* Limit xffff. */
.word 0x0000 /* Base xxxx0000. */
.byte 0x00 /* Base xx00xxxx. */
.byte (0x8 /* Type 8. */ | (1 << 4) /* Code. */ \
| (0 << 5) /* Ring 0. */ | (1 << 7) /* Present. */)
.byte (0xf /* Limit fxxxx. */ | (0 << 4) /* AVL flag. */ \
| (1 << 5) /* 64-bit. */ | (0 << 6) \
| (1 << 7) /* 4K granular. */)
.byte 0x00 /* Base 00xxxxxx. */
/* Data segment*/
.word 0xffff /* Limit xffff. */
.word 0x0000 /* Base xxxx0000. */
.byte 0x00 /* Base xx00xxxx. */
.byte (0x0 /* Type 0. */ | (0 << 4) /* Data. */ \
| (0 << 5) /* Ring 0. */ | (1 << 7) /* Present. */)
.byte (0xf /* Limit fxxxx. */ | (0 << 4) /* AVL flag. */ \
| (0 << 5) /* Data. */ | (0 << 6) \
| (1 << 7) /* 4K granular. */)
.byte 0x00 /* Base 00xxxxxx. */
/* Compatibility segment. */
.word 0xffff /* Limit xffff. */
.word 0x0000 /* Base xxxx0000. */
.byte 0x00 /* Base xx00xxxx. */
.byte (0x8 /* Type 8. */ | (1 << 4) /* Code. */ \
| (0 << 5) /* Ring 0. */ | (1 << 7) /* Present. */)
.byte (0xf /* Limit fxxxx. */ | (0 << 4) /* AVL flag. */ \
| (0 << 5) /* 32-bit. */ | (1 << 6) /* 32-bit. */ \
| (1 << 7) /* 4K granular. */)
.byte 0x00 /* Base 00xxxxxx. */
LOCAL(gdt_end):
#endif
VARIABLE(grub_relocator64_end)
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