linux-sg2042/arch/avr32/lib/clear_user.S

77 lines
1.2 KiB
ArmAsm

/*
* Copyright 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <asm/page.h>
#include <asm/thread_info.h>
#include <asm/asm.h>
.text
.align 1
.global clear_user
.type clear_user, "function"
clear_user:
branch_if_kernel r8, __clear_user
ret_if_privileged r8, r12, r11, r11
.global __clear_user
.type __clear_user, "function"
__clear_user:
mov r9, r12
mov r8, 0
andl r9, 3, COH
brne 5f
1: sub r11, 4
brlt 2f
10: st.w r12++, r8
sub r11, 4
brge 10b
2: sub r11, -4
reteq 0
/* Unaligned count or address */
bld r11, 1
brcc 12f
11: st.h r12++, r8
sub r11, 2
reteq 0
12: st.b r12++, r8
retal 0
/* Unaligned address */
5: cp.w r11, 4
brlt 2b
lsl r9, 2
add pc, pc, r9
13: st.b r12++, r8
sub r11, 1
14: st.b r12++, r8
sub r11, 1
15: st.b r12++, r8
sub r11, 1
rjmp 1b
.size clear_user, . - clear_user
.size __clear_user, . - __clear_user
.section .fixup, "ax"
.align 1
18: sub r11, -4
19: retal r11
.section __ex_table, "a"
.align 2
.long 10b, 18b
.long 11b, 19b
.long 12b, 19b
.long 13b, 19b
.long 14b, 19b
.long 15b, 19b