/* $OpenBSD: bcopy_page.S,v 1.3 2018/08/06 18:39:13 kettenis Exp $ */ /* $NetBSD: bcopy_page.S,v 1.7 2003/10/13 21:03:13 scw Exp $ */ /* * Copyright (c) 1995 Scott Stevens * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Scott Stevens. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * RiscBSD kernel project * * bcopy_page.S * * page optimised bcopy and bzero routines * * Created : 08/04/95 */ #include "assym.h" #include /* #define BIG_LOOPS */ /* * bcopy_page(src, dest) * * Optimised copy page routine. * * On entry: * r0 - src address * r1 - dest address * * Requires: * number of bytes per page (PAGE_SIZE) is a multiple of 512 (BIG_LOOPS), 128 * otherwise. */ #define CHUNK_SIZE 32 #define PREFETCH_FIRST_CHUNK /* nothing */ #define PREFETCH_NEXT_CHUNK /* nothing */ #ifndef COPY_CHUNK #define COPY_CHUNK \ PREFETCH_NEXT_CHUNK ; \ ldmia r0!, {r3-r8,ip,lr} ; \ stmia r1!, {r3-r8,ip,lr} #endif /* ! COPY_CHUNK */ #ifndef SAVE_REGS #define SAVE_REGS stmfd sp!, {r4-r8, lr} #define RESTORE_REGS ldmfd sp!, {r4-r8, pc} #endif ENTRY(bcopy_page) PREFETCH_FIRST_CHUNK SAVE_REGS #ifdef BIG_LOOPS mov r2, #(PAGE_SIZE >> 9) #else mov r2, #(PAGE_SIZE >> 7) #endif 1: COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK #ifdef BIG_LOOPS /* There is little point making the loop any larger; unless we are running with the cache off, the load/store overheads will completely dominate this loop. */ COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK COPY_CHUNK #endif subs r2, r2, #1 bne 1b RESTORE_REGS /* ...and return. */ /* * bzero_page(dest) * * Optimised zero page routine. * * On entry: * r0 - dest address * * Requires: * number of bytes per page (PAGE_SIZE) is a multiple of 512 (BIG_LOOPS), 128 * otherwise */ ENTRY(bzero_page) stmfd sp!, {r4-r8, lr} #ifdef BIG_LOOPS mov r2, #(PAGE_SIZE >> 9) #else mov r2, #(PAGE_SIZE >> 7) #endif mov r3, #0 mov r4, #0 mov r5, #0 mov r6, #0 mov r7, #0 mov r8, #0 mov ip, #0 mov lr, #0 1: stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} #ifdef BIG_LOOPS /* There is little point making the loop any larger; unless we are running with the cache off, the load/store overheads will completely dominate this loop. */ stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} stmia r0!, {r3-r8,ip,lr} #endif subs r2, r2, #1 bne 1b ldmfd sp!, {r4-r8, pc}