bsdstart.S revision 1.1.4.4
1 1.1.4.4 skrll /* $NetBSD: bsdstart.S,v 1.1.4.4 2004/09/21 13:14:11 skrll Exp $ */ 2 1.1.4.2 skrll 3 1.1.4.2 skrll /* 4 1.1.4.2 skrll * Copyright (c) 1995 L. Weppelman 5 1.1.4.2 skrll * All rights reserved. 6 1.1.4.2 skrll * 7 1.1.4.2 skrll * Redistribution and use in source and binary forms, with or without 8 1.1.4.2 skrll * modification, are permitted provided that the following conditions 9 1.1.4.2 skrll * are met: 10 1.1.4.2 skrll * 1. Redistributions of source code must retain the above copyright 11 1.1.4.2 skrll * notice, this list of conditions and the following disclaimer. 12 1.1.4.2 skrll * 2. Redistributions in binary form must reproduce the above copyright 13 1.1.4.2 skrll * notice, this list of conditions and the following disclaimer in the 14 1.1.4.2 skrll * documentation and/or other materials provided with the distribution. 15 1.1.4.2 skrll * 3. All advertising materials mentioning features or use of this software 16 1.1.4.2 skrll * must display the following acknowledgement: 17 1.1.4.2 skrll * This product includes software developed by Leo Weppelman. 18 1.1.4.2 skrll * 4. The name of the author may not be used to endorse or promote products 19 1.1.4.2 skrll * derived from this software without specific prior written permission 20 1.1.4.2 skrll * 21 1.1.4.2 skrll * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 1.1.4.2 skrll * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 1.1.4.2 skrll * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 1.1.4.2 skrll * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 1.1.4.2 skrll * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 1.1.4.2 skrll * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 1.1.4.2 skrll * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 1.1.4.2 skrll * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 1.1.4.2 skrll * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 1.1.4.2 skrll * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 1.1.4.2 skrll */ 32 1.1.4.2 skrll 33 1.1.4.2 skrll /* 34 1.1.4.2 skrll * This function sets up the registers according to the kernel parameter block, 35 1.1.4.2 skrll * disables the MMU and jumps to the kernel. 36 1.1.4.2 skrll * 37 1.1.4.2 skrll * bsd_startup(struct kparamb *) 38 1.1.4.2 skrll */ 39 1.1.4.2 skrll 40 1.1.4.2 skrll #ifndef TOSTOOLS 41 1.1.4.2 skrll #include <machine/asm.h> 42 1.1.4.2 skrll #endif 43 1.1.4.2 skrll 44 1.1.4.2 skrll #ifdef TOSTOOLS 45 1.1.4.2 skrll .globl _bsd_startup 46 1.1.4.2 skrll _bsd_startup: 47 1.1.4.2 skrll #else 48 1.1.4.2 skrll ENTRY_NOPROFILE(bsd_startup) 49 1.1.4.2 skrll #endif 50 1.1.4.2 skrll movw #0x2700,%sr 51 1.1.4.2 skrll 52 1.1.4.2 skrll | the BSD kernel wants values into the following registers: 53 1.1.4.2 skrll | d0: ttmem-size 54 1.1.4.2 skrll | d1: stmem-size 55 1.1.4.2 skrll | d2: cputype 56 1.1.4.2 skrll | d3: boothowto 57 1.1.4.2 skrll | d4: length of loaded kernel 58 1.1.4.2 skrll | d5: start of fastram 59 1.1.4.2 skrll | a0: start of loaded kernel 60 1.1.4.2 skrll | a1: end of symbols (esym) 61 1.1.4.2 skrll | All other registers zeroed for possible future requirements. 62 1.1.4.2 skrll 63 1.1.4.2 skrll movl %sp@(4),%a3 | a3 points to parameter block 64 1.1.4.2 skrll #ifdef TOSTOOLS 65 1.1.4.2 skrll lea _bsd_startup,%sp | make sure we have a good stack *** 66 1.1.4.2 skrll #endif 67 1.1.4.2 skrll movl %a3@,%a0 | loaded kernel 68 1.1.4.2 skrll movl %a3@(8),%d0 | kernel entry point 69 1.1.4.2 skrll addl %a0,%d0 | added makes our absolute entry point 70 1.1.4.2 skrll movl %d0,%sp@- | push entry point *** 71 1.1.4.2 skrll movl %a3@(12),%d1 | stmem-size 72 1.1.4.2 skrll movl %a3@(16),%d0 | ttmem-size 73 1.1.4.2 skrll movl %a3@(20),%d2 | bootflags 74 1.1.4.2 skrll movl %a3@(24),%d3 | boothowto 75 1.1.4.2 skrll movl %a3@(4),%d4 | length of loaded kernel 76 1.1.4.2 skrll movl %a3@(28),%d5 | start of fastram 77 1.1.4.2 skrll movl %a3@(32),%a1 | end of symbols 78 1.1.4.2 skrll subl %a5,%a5 | target, load to 0 79 1.1.4.2 skrll movl %d2,%d6 80 1.1.4.2 skrll andb #0x50,%d6 | Is this an 68040/68060? 81 1.1.4.2 skrll beqs 0f 82 1.1.4.2 skrll 83 1.1.4.2 skrll | Turn off 68040 type MMU 84 1.1.4.2 skrll .word 0x4e7b,0xd003 | movec a5,tc 85 1.1.4.2 skrll .word 0x4e7b,0xd806 | movec a5,urp 86 1.1.4.2 skrll .word 0x4e7b,0xd807 | movec a5,srp 87 1.1.4.2 skrll .word 0x4e7b,0xd004 | movec a5,itt0 88 1.1.4.2 skrll .word 0x4e7b,0xd005 | movec a5,itt1 89 1.1.4.2 skrll .word 0x4e7b,0xd006 | movec a5,dtt0 90 1.1.4.2 skrll .word 0x4e7b,0xd007 | movec a5,dtt1 91 1.1.4.2 skrll .word 0xf4f8 | cpusha bc - push and inval caches 92 1.1.4.2 skrll bras 1f 93 1.1.4.2 skrll 94 1.1.4.2 skrll 0: lea %pc@(zero),%a3 95 1.1.4.2 skrll pmove %a3@,%tc | Turn off MMU 96 1.1.4.2 skrll pmove %a3@(-4),%crp | crp = nullrp 97 1.1.4.2 skrll pmove %a3@(-4),%srp | srp = nullrp 98 1.1.4.2 skrll btst #3,%d2 | Is this an 68030? 99 1.1.4.2 skrll beqs 1f 100 1.1.4.2 skrll 101 1.1.4.2 skrll | Turn off 68030 TT registers 102 1.1.4.2 skrll .word 0xf013,0x0800 | pmove a3@,tt0 103 1.1.4.2 skrll .word 0xf013,0x0c00 | pmove a3@,tt1 104 1.1.4.2 skrll 105 1.1.4.2 skrll 1: movq #0,%d6 | would have known contents 106 1.1.4.2 skrll movc %d6,%cacr | turn off the caches 107 1.1.4.2 skrll movl %d6,%d7 108 1.1.4.2 skrll movl %d6,%a2 109 1.1.4.2 skrll movl %d6,%a3 110 1.1.4.2 skrll movl %d6,%a4 111 1.1.4.2 skrll movl %d6,%a5 112 1.1.4.2 skrll movl %d6,%a6 113 1.1.4.2 skrll rts | enter kernel at address on stack *** 114 1.1.4.2 skrll 115 1.1.4.2 skrll | A do-nothing MMU root pointer (includes the following long as well) 116 1.1.4.2 skrll | Note that the above code makes assumptions about the order of the following 117 1.1.4.2 skrll | items. 118 1.1.4.2 skrll 119 1.1.4.2 skrll nullrp: .long 0x80000202 120 1.1.4.2 skrll zero: .long 0 121
Indexes created Tue Oct 21 19:09:51 GMT 2025