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