2 * linux/arch/arm/lib/copypage.S
4 * Copyright (C) 1995-1999 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * ASM optimised string functions
12 #include <linux/linkage.h>
13 #include <asm/assembler.h>
14 #include <asm/asm-offsets.h>
15 #include <asm/cache.h>
16 #include <asm/export.h>
18 #define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 ))
23 * StrongARM optimised copy_page routine
24 * now 1.78bytes/cycle, was 1.60 bytes/cycle (50MHz bus -> 89MB/s)
25 * Note that we probably achieve closer to the 100MB/s target with
26 * the core clock switching.
29 stmfd sp!, {r4, lr} @ 2
31 PLD( pld [r1, #L1_CACHE_BYTES] )
32 mov r2, #COPY_COUNT @ 1
33 ldmia r1!, {r3, r4, ip, lr} @ 4+1
34 1: PLD( pld [r1, #2 * L1_CACHE_BYTES])
35 PLD( pld [r1, #3 * L1_CACHE_BYTES])
37 .rept (2 * L1_CACHE_BYTES / 16 - 1)
38 stmia r0!, {r3, r4, ip, lr} @ 4
39 ldmia r1!, {r3, r4, ip, lr} @ 4
42 stmia r0!, {r3, r4, ip, lr} @ 4
43 ldmgtia r1!, {r3, r4, ip, lr} @ 4
45 PLD( ldmeqia r1!, {r3, r4, ip, lr} )
47 ldmfd sp!, {r4, pc} @ 3
49 EXPORT_SYMBOL(copy_page)