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#include <asm/export.h> 17 18#define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 )) 19 20 .text 21 .align 5 22/* 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. 27 */ 28ENTRY(copy_page) 29 stmfd sp!, {r4, lr} @ 2 30 PLD( pld [r1, #0] ) 31 PLD( pld [r1, #L1_CACHE_BYTES] ) 32 mov r2, #COPY_COUNT @ 1 33 ldmia r1!, {r3, r4, ip, lr} @ 4+1 341: PLD( pld [r1, #2 * L1_CACHE_BYTES]) 35 PLD( pld [r1, #3 * L1_CACHE_BYTES]) 362: 37 .rept (2 * L1_CACHE_BYTES / 16 - 1) 38 stmia r0!, {r3, r4, ip, lr} @ 4 39 ldmia r1!, {r3, r4, ip, lr} @ 4 40 .endr 41 subs r2, r2, #1 @ 1 42 stmia r0!, {r3, r4, ip, lr} @ 4 43 ldmgtia r1!, {r3, r4, ip, lr} @ 4 44 bgt 1b @ 1 45 PLD( ldmeqia r1!, {r3, r4, ip, lr} ) 46 PLD( beq 2b ) 47 ldmfd sp!, {r4, pc} @ 3 48ENDPROC(copy_page) 49EXPORT_SYMBOL(copy_page) 50