80 lines
2.2 KiB
ArmAsm
80 lines
2.2 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 <linux/init.h>
|
|
#include <asm/asm-offsets.h>
|
|
|
|
.text
|
|
.align 5
|
|
/*
|
|
* ARMv4 optimised copy_user_page
|
|
*
|
|
* We flush the destination cache lines just before we write the data into the
|
|
* corresponding address. Since the Dcache is read-allocate, this removes the
|
|
* Dcache aliasing issue. The writes will be forwarded to the write buffer,
|
|
* and merged as appropriate.
|
|
*
|
|
* Note: We rely on all ARMv4 processors implementing the "invalidate D line"
|
|
* instruction. If your processor does not supply this, you have to write your
|
|
* own copy_user_page that does the right thing.
|
|
*/
|
|
ENTRY(v4wb_copy_user_page)
|
|
stmfd sp!, {r4, lr} @ 2
|
|
mov r2, #PAGE_SZ/64 @ 1
|
|
ldmia r1!, {r3, r4, ip, lr} @ 4
|
|
1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
|
|
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
|
|
mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
|
|
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
|
|
ldmneia r1!, {r3, r4, ip, lr} @ 4
|
|
bne 1b @ 1
|
|
mcr p15, 0, r1, c7, c10, 4 @ 1 drain WB
|
|
ldmfd sp!, {r4, pc} @ 3
|
|
|
|
.align 5
|
|
/*
|
|
* ARMv4 optimised clear_user_page
|
|
*
|
|
* Same story as above.
|
|
*/
|
|
ENTRY(v4wb_clear_user_page)
|
|
str lr, [sp, #-4]!
|
|
mov r1, #PAGE_SZ/64 @ 1
|
|
mov r2, #0 @ 1
|
|
mov r3, #0 @ 1
|
|
mov ip, #0 @ 1
|
|
mov lr, #0 @ 1
|
|
1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
|
|
stmia r0!, {r2, r3, ip, lr} @ 4
|
|
stmia r0!, {r2, r3, ip, lr} @ 4
|
|
mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
|
|
stmia r0!, {r2, r3, ip, lr} @ 4
|
|
stmia r0!, {r2, r3, ip, lr} @ 4
|
|
subs r1, r1, #1 @ 1
|
|
bne 1b @ 1
|
|
mcr p15, 0, r1, c7, c10, 4 @ 1 drain WB
|
|
ldr pc, [sp], #4
|
|
|
|
__INITDATA
|
|
|
|
.type v4wb_user_fns, #object
|
|
ENTRY(v4wb_user_fns)
|
|
.long v4wb_clear_user_page
|
|
.long v4wb_copy_user_page
|
|
.size v4wb_user_fns, . - v4wb_user_fns
|