kernel-ark/arch/arm/lib/copy_page.S
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

47 lines
1.3 KiB
ArmAsm

/*
* 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/constants.h>
#define COPY_COUNT (PAGE_SZ/64 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, #32] )
mov r2, #COPY_COUNT @ 1
ldmia r1!, {r3, r4, ip, lr} @ 4+1
1: PLD( pld [r1, #64] )
PLD( pld [r1, #96] )
2: stmia r0!, {r3, r4, ip, lr} @ 4
ldmia r1!, {r3, r4, ip, lr} @ 4+1
stmia r0!, {r3, r4, ip, lr} @ 4
ldmia r1!, {r3, r4, ip, lr} @ 4+1
stmia r0!, {r3, r4, ip, lr} @ 4
ldmia r1!, {r3, r4, ip, lr} @ 4
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 )
LOADREGS(fd, sp!, {r4, pc}) @ 3