121 lines
2.7 KiB
ArmAsm
121 lines
2.7 KiB
ArmAsm
/*
|
|
* relocate_kernel.S - put the kernel image in place to boot
|
|
* Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
|
|
*
|
|
* This source code is licensed under the GNU General Public License,
|
|
* Version 2. See the file COPYING for more details.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
|
|
/*
|
|
* Must be relocatable PIC code callable as a C function, that once
|
|
* it starts can not use the previous processes stack.
|
|
*/
|
|
.globl relocate_new_kernel
|
|
relocate_new_kernel:
|
|
/* read the arguments and say goodbye to the stack */
|
|
movl 4(%esp), %ebx /* page_list */
|
|
movl 8(%esp), %ebp /* reboot_code_buffer */
|
|
movl 12(%esp), %edx /* start address */
|
|
movl 16(%esp), %ecx /* cpu_has_pae */
|
|
|
|
/* zero out flags, and disable interrupts */
|
|
pushl $0
|
|
popfl
|
|
|
|
/* set a new stack at the bottom of our page... */
|
|
lea 4096(%ebp), %esp
|
|
|
|
/* store the parameters back on the stack */
|
|
pushl %edx /* store the start address */
|
|
|
|
/* Set cr0 to a known state:
|
|
* 31 0 == Paging disabled
|
|
* 18 0 == Alignment check disabled
|
|
* 16 0 == Write protect disabled
|
|
* 3 0 == No task switch
|
|
* 2 0 == Don't do FP software emulation.
|
|
* 0 1 == Proctected mode enabled
|
|
*/
|
|
movl %cr0, %eax
|
|
andl $~((1<<31)|(1<<18)|(1<<16)|(1<<3)|(1<<2)), %eax
|
|
orl $(1<<0), %eax
|
|
movl %eax, %cr0
|
|
|
|
/* clear cr4 if applicable */
|
|
testl %ecx, %ecx
|
|
jz 1f
|
|
/* Set cr4 to a known state:
|
|
* Setting everything to zero seems safe.
|
|
*/
|
|
movl %cr4, %eax
|
|
andl $0, %eax
|
|
movl %eax, %cr4
|
|
|
|
jmp 1f
|
|
1:
|
|
|
|
/* Flush the TLB (needed?) */
|
|
xorl %eax, %eax
|
|
movl %eax, %cr3
|
|
|
|
/* Do the copies */
|
|
movl %ebx, %ecx
|
|
jmp 1f
|
|
|
|
0: /* top, read another word from the indirection page */
|
|
movl (%ebx), %ecx
|
|
addl $4, %ebx
|
|
1:
|
|
testl $0x1, %ecx /* is it a destination page */
|
|
jz 2f
|
|
movl %ecx, %edi
|
|
andl $0xfffff000, %edi
|
|
jmp 0b
|
|
2:
|
|
testl $0x2, %ecx /* is it an indirection page */
|
|
jz 2f
|
|
movl %ecx, %ebx
|
|
andl $0xfffff000, %ebx
|
|
jmp 0b
|
|
2:
|
|
testl $0x4, %ecx /* is it the done indicator */
|
|
jz 2f
|
|
jmp 3f
|
|
2:
|
|
testl $0x8, %ecx /* is it the source indicator */
|
|
jz 0b /* Ignore it otherwise */
|
|
movl %ecx, %esi /* For every source page do a copy */
|
|
andl $0xfffff000, %esi
|
|
|
|
movl $1024, %ecx
|
|
rep ; movsl
|
|
jmp 0b
|
|
|
|
3:
|
|
|
|
/* To be certain of avoiding problems with self-modifying code
|
|
* I need to execute a serializing instruction here.
|
|
* So I flush the TLB, it's handy, and not processor dependent.
|
|
*/
|
|
xorl %eax, %eax
|
|
movl %eax, %cr3
|
|
|
|
/* set all of the registers to known values */
|
|
/* leave %esp alone */
|
|
|
|
xorl %eax, %eax
|
|
xorl %ebx, %ebx
|
|
xorl %ecx, %ecx
|
|
xorl %edx, %edx
|
|
xorl %esi, %esi
|
|
xorl %edi, %edi
|
|
xorl %ebp, %ebp
|
|
ret
|
|
relocate_new_kernel_end:
|
|
|
|
.globl relocate_new_kernel_size
|
|
relocate_new_kernel_size:
|
|
.long relocate_new_kernel_end - relocate_new_kernel
|