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/* ----------------------------------------------------------------------- *
*
* Copyright 2013 Intel Corporation; author: Matt Fleming
*
* This program 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, Inc., 51 Franklin St, Fifth Floor,
* Boston MA 02110-1301, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
#define CR0_PG_FLAG 0x80000000
#define MSR_EFER 0xc0000080
.globl kernel_jump
.type kernel_jump,@function
.code64
kernel_jump:
cli
/*
* Setup our segment selector (0x10) and return address (%rdi)
* on the stack in preparation for the far return below.
*/
mov $0x1000000000, %rcx
addq %rcx, %rdi
pushq %rdi
.code32
pm_code:
/* Disable IA-32e mode by clearing IA32_EFER.LME */
xorl %eax, %eax
xorl %edx, %edx
movl $MSR_EFER, %ecx
wrmsr
/* Turn off paging to disable long mode */
movl %cr0, %eax
andl $~CR0_PG_FLAG, %eax
movl %eax, %cr0
/* Far return */
lret
.code64
.align 4
.globl efi_handover_32
.type efi_handover_32,@function
efi_handover_32:
movl $38, errno(%rip) /* ENOSYS */
ret
.globl efi_handover_64
.globl efi_handover
.type efi_handover_64,@function
.type efi_handover,@function
efi_handover_64:
efi_handover:
add $512, %rcx
cli
jmp *%rcx
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