bcopy_page.S revision 1.2
1 /* $NetBSD: bcopy_page.S,v 1.2 2001/08/11 12:44:42 chris Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Scott Stevens 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Scott Stevens. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 * 32 * RiscBSD kernel project 33 * 34 * bcopy_page.S 35 * 36 * page optimised bcopy and bzero routines 37 * 38 * Created : 08/04/95 39 */ 40 41 #include <machine/param.h> 42 #include <machine/asm.h> 43 44 /* #define BIG_LOOPS */ 45 46 /* 47 * bcopy_page(src, dest) 48 * 49 * Optimised copy page routine. 50 * 51 * On entry: 52 * r0 - src address 53 * r1 - dest address 54 * 55 * Requires: 56 * number of bytes per page (NBPG) is a multiple of 512 (BIG_LOOPS), 128 57 * otherwise. 58 */ 59 60 ENTRY(bcopy_page) 61 stmfd sp!, {r4-r8, lr} 62 #ifdef BIG_LOOPS 63 mov r2, #(NBPG >> 9) 64 #else 65 mov r2, #(NBPG >> 7) 66 #endif 67 68 Lloopcopy: 69 ldmia r0!, {r3-r8,ip,lr} 70 stmia r1!, {r3-r8,ip,lr} 71 ldmia r0!, {r3-r8,ip,lr} 72 stmia r1!, {r3-r8,ip,lr} 73 ldmia r0!, {r3-r8,ip,lr} 74 stmia r1!, {r3-r8,ip,lr} 75 ldmia r0!, {r3-r8,ip,lr} 76 stmia r1!, {r3-r8,ip,lr} 77 78 #ifdef BIG_LOOPS 79 /* There is little point making the loop any larger; unless we are 80 running with the cache off, the load/store overheads will 81 completely dominate this loop. */ 82 ldmia r0!, {r3-r8,ip,lr} 83 stmia r1!, {r3-r8,ip,lr} 84 ldmia r0!, {r3-r8,ip,lr} 85 stmia r1!, {r3-r8,ip,lr} 86 ldmia r0!, {r3-r8,ip,lr} 87 stmia r1!, {r3-r8,ip,lr} 88 ldmia r0!, {r3-r8,ip,lr} 89 stmia r1!, {r3-r8,ip,lr} 90 91 ldmia r0!, {r3-r8,ip,lr} 92 stmia r1!, {r3-r8,ip,lr} 93 ldmia r0!, {r3-r8,ip,lr} 94 stmia r1!, {r3-r8,ip,lr} 95 ldmia r0!, {r3-r8,ip,lr} 96 stmia r1!, {r3-r8,ip,lr} 97 ldmia r0!, {r3-r8,ip,lr} 98 stmia r1!, {r3-r8,ip,lr} 99 100 ldmia r0!, {r3-r8,ip,lr} 101 stmia r1!, {r3-r8,ip,lr} 102 ldmia r0!, {r3-r8,ip,lr} 103 stmia r1!, {r3-r8,ip,lr} 104 ldmia r0!, {r3-r8,ip,lr} 105 stmia r1!, {r3-r8,ip,lr} 106 ldmia r0!, {r3-r8,ip,lr} 107 stmia r1!, {r3-r8,ip,lr} 108 #endif 109 subs r2, r2, #1 110 bne Lloopcopy 111 112 ldmfd sp!, {r4-r8, pc} 113 114 /* 115 * bzero_page(dest) 116 * 117 * Optimised zero page routine. 118 * 119 * On entry: 120 * r0 - dest address 121 * 122 * Requires: 123 * number of bytes per page (NBPG) is a multiple of 512 (BIG_LOOPS), 128 124 * otherwise 125 */ 126 127 ENTRY(bzero_page) 128 stmfd sp!, {r4-r8, lr} 129 #ifdef BIG_LOOPS 130 mov r2, #(NBPG >> 9) 131 #else 132 mov r2, #(NBPG >> 7) 133 #endif 134 mov r3, #0 135 mov r4, #0 136 mov r5, #0 137 mov r6, #0 138 mov r7, #0 139 mov r8, #0 140 mov ip, #0 141 mov lr, #0 142 143 Lloopzero: 144 stmia r0!, {r3-r8,ip,lr} 145 stmia r0!, {r3-r8,ip,lr} 146 stmia r0!, {r3-r8,ip,lr} 147 stmia r0!, {r3-r8,ip,lr} 148 149 #ifdef BIG_LOOPS 150 /* There is little point making the loop any larger; unless we are 151 running with the cache off, the load/store overheads will 152 completely dominate this loop. */ 153 stmia r0!, {r3-r8,ip,lr} 154 stmia r0!, {r3-r8,ip,lr} 155 stmia r0!, {r3-r8,ip,lr} 156 stmia r0!, {r3-r8,ip,lr} 157 158 stmia r0!, {r3-r8,ip,lr} 159 stmia r0!, {r3-r8,ip,lr} 160 stmia r0!, {r3-r8,ip,lr} 161 stmia r0!, {r3-r8,ip,lr} 162 163 stmia r0!, {r3-r8,ip,lr} 164 stmia r0!, {r3-r8,ip,lr} 165 stmia r0!, {r3-r8,ip,lr} 166 stmia r0!, {r3-r8,ip,lr} 167 168 #endif 169 170 subs r2, r2, #1 171 bne Lloopzero 172 173 ldmfd sp!, {r4-r8, pc} 174
Indexes created Tue Sep 30 07:10:03 GMT 2025