/* * linux/arch/arm/lib/copypage-v4.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 * * This is for CPUs with a writethrough cache and 'flush ID cache' is * the only supported cache operation. */ #include #include #include .text .align 5 /* * ARMv4 optimised copy_user_page * * Since we have writethrough caches, we don't have to worry about * dirty data in the cache. However, we do have to ensure that * subsequent reads are up to date. */ ENTRY(v4wt_copy_user_page) stmfd sp!, {r4, lr} @ 2 mov r2, #PAGE_SZ/64 @ 1 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 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, r2, c7, c7, 0 @ flush ID cache ldmfd sp!, {r4, pc} @ 3 .align 5 /* * ARMv4 optimised clear_user_page * * Same story as above. */ ENTRY(v4wt_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: stmia r0!, {r2, r3, ip, lr} @ 4 stmia r0!, {r2, r3, ip, lr} @ 4 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, r2, c7, c7, 0 @ flush ID cache ldr pc, [sp], #4 __INITDATA .type v4wt_user_fns, #object ENTRY(v4wt_user_fns) .long v4wt_clear_user_page .long v4wt_copy_user_page .size v4wt_user_fns, . - v4wt_user_fns