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/*
* linux/arch/arm/lib/copypage.S
*
* Copyright (C) 1995-1999 Russell King
*
* 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.
*
* ASM optimised string functions
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/cache.h>
#include <asm/export.h>
#define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 ))
.text
.align 5
/*
* StrongARM optimised copy_page routine
* now 1.78bytes/cycle, was 1.60 bytes/cycle (50MHz bus -> 89MB/s)
* Note that we probably achieve closer to the 100MB/s target with
* the core clock switching.
*/
ENTRY(copy_page)
stmfd sp!, {r4, lr} @ 2
PLD( pld [r1, #0] )
PLD( pld [r1, #L1_CACHE_BYTES] )
mov r2, #COPY_COUNT @ 1
ldmia r1!, {r3, r4, ip, lr} @ 4+1
1: PLD( pld [r1, #2 * L1_CACHE_BYTES])
PLD( pld [r1, #3 * L1_CACHE_BYTES])
2:
.rept (2 * L1_CACHE_BYTES / 16 - 1)
stmia r0!, {r3, r4, ip, lr} @ 4
ldmia r1!, {r3, r4, ip, lr} @ 4
.endr
subs r2, r2, #1 @ 1
stmia r0!, {r3, r4, ip, lr} @ 4
ldmgtia r1!, {r3, r4, ip, lr} @ 4
bgt 1b @ 1
PLD( ldmeqia r1!, {r3, r4, ip, lr} )
PLD( beq 2b )
ldmfd sp!, {r4, pc} @ 3
ENDPROC(copy_page)
EXPORT_SYMBOL(copy_page)
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