1/* 2 * linux/arch/arm/lib/copypage.S 3 * 4 * Copyright (C) 1995-1999 Russell King 5 * 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. 9 * 10 * ASM optimised string functions 11 */ 12#include <linux/linkage.h> 13#include <asm/assembler.h> 14#include <asm/asm-offsets.h> 15#include <asm/cache.h> 16 17#define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 )) 18 19 .text 20 .align 5 21/* 22 * StrongARM optimised copy_page routine 23 * now 1.78bytes/cycle, was 1.60 bytes/cycle (50MHz bus -> 89MB/s) 24 * Note that we probably achieve closer to the 100MB/s target with 25 * the core clock switching. 26 */ 27ENTRY(copy_page) 28 stmfd sp!, {r4, lr} @ 2 29 PLD( pld [r1, #0] ) 30 PLD( pld [r1, #L1_CACHE_BYTES] ) 31 mov r2, #COPY_COUNT @ 1 32 ldmia r1!, {r3, r4, ip, lr} @ 4+1 331: PLD( pld [r1, #2 * L1_CACHE_BYTES]) 34 PLD( pld [r1, #3 * L1_CACHE_BYTES]) 352: 36 .rept (2 * L1_CACHE_BYTES / 16 - 1) 37 stmia r0!, {r3, r4, ip, lr} @ 4 38 ldmia r1!, {r3, r4, ip, lr} @ 4 39 .endr 40 subs r2, r2, #1 @ 1 41 stmia r0!, {r3, r4, ip, lr} @ 4 42 ldmgtia r1!, {r3, r4, ip, lr} @ 4 43 bgt 1b @ 1 44 PLD( ldmeqia r1!, {r3, r4, ip, lr} ) 45 PLD( beq 2b ) 46 ldmfd sp!, {r4, pc} @ 3 47ENDPROC(copy_page) 48