start.S revision 1.1
1 /* $NetBSD: start.S,v 1.1 2005/12/29 15:20:09 tsutsui Exp $ */ 2 3 /*- 4 * Copyright (c) 2004 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by UCHIYAMA Yasushi. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <mips/regdef.h> 40 41 .set noreorder 42 .set mips3 43 .align 2 44 .text 45 /* 46 * Entry point. 47 */ 48 .globl start 49 start: 50 nop 51 nop 52 nop 53 nop 54 la sp, _ftext 55 56 mfc0 t0, $12 57 lui t1, 0x0040 /* BEV : use IPL's exception vector. */ 58 and t0, t0, t1 59 mtc0 t0, $12 60 nop 61 la t0, main 62 move a1, v0 63 jr t0 64 move a2, v1 /* v1 = mainfo */ 65 1: b 1b 66 nop 67 /* NOTREACHED */ 68 69 #if 0 /* ROM putc test */ 70 li a0, 50 /* x-pos */ 71 2: li a2, 90 /* 'Z' */ 72 lui v0, 0xbfc0 73 ori v0, 0xff60 74 li a1, 50 /* y-pos */ 75 jal v0 76 nop 77 b 2b 78 addiu a0, a0, 12 79 /* NOTREACHED */ 80 #endif 81 #if 0 /* Frame buffer (TLB kseg2 mapped by IPL) test */ 82 move a3, zero 83 xori a3, a3, 0x00 84 3: sll v0, a3, 0x18 85 sra a2, v0, 0x18 86 lui a0, 0xf000 87 move v1, zero 88 lui a1, 0x1 89 ori a1, a1, 0xffff 90 2: sb a2, 0(a0) 91 addiu v1, v1, 1 92 slt v0, a1, v1 93 addiu a0, a0, 1 94 beqz v0, 2b 95 nop 96 xori a3, a3, 0xff 97 j 3b 98 nop 99 /* NOTREACHED */ 100 #endif 101 102 /* 103 * void tlb_read(int index, void *) 104 */ 105 .global tlb_read 106 .ent tlb_read 107 tlb_read: 108 mtc0 a0, $0 /* Index Register */ 109 nop; nop; nop; nop; 110 tlbr 111 nop; nop; nop; nop; 112 mfc0 t0, $5 /* PageMask */ 113 nop; nop; nop; nop; 114 mfc0 t1, $10 /* EntryHi */ 115 nop; nop; nop; nop; 116 mfc0 t2, $2 /* EntryLo0 */ 117 nop; nop; nop; nop; 118 mfc0 t3, $3 /* EntryLo1 */ 119 nop; nop; nop; nop; 120 sw t0, 0(a1) 121 sw t1, 4(a1) 122 sw t2, 8(a1) 123 sw t3, 12(a1) 124 jr ra 125 nop 126 .end tlb_read 127
Indexes created Mon Oct 20 01:09:56 GMT 2025