1 1.5 rin /* $NetBSD: srt0.s,v 1.5 2025/08/30 09:27:06 rin Exp $ */ 2 1.1 sakamoto 3 1.1 sakamoto /*- 4 1.1 sakamoto * Copyright (C) 1995-1997 Gary Thomas (gdt (at) linuxppc.org) 5 1.1 sakamoto * All rights reserved. 6 1.1 sakamoto * 7 1.1 sakamoto * Redistribution and use in source and binary forms, with or without 8 1.1 sakamoto * modification, are permitted provided that the following conditions 9 1.1 sakamoto * are met: 10 1.1 sakamoto * 1. Redistributions of source code must retain the above copyright 11 1.1 sakamoto * notice, this list of conditions and the following disclaimer. 12 1.1 sakamoto * 2. Redistributions in binary form must reproduce the above copyright 13 1.1 sakamoto * notice, this list of conditions and the following disclaimer in the 14 1.1 sakamoto * documentation and/or other materials provided with the distribution. 15 1.1 sakamoto * 3. All advertising materials mentioning features or use of this software 16 1.1 sakamoto * must display the following acknowledgement: 17 1.1 sakamoto * This product includes software developed by Gary Thomas. 18 1.1 sakamoto * 4. The name of the author may not be used to endorse or promote products 19 1.1 sakamoto * derived from this software without specific prior written permission. 20 1.1 sakamoto * 21 1.1 sakamoto * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 1.1 sakamoto * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 1.1 sakamoto * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 1.1 sakamoto * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 1.1 sakamoto * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 1.1 sakamoto * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 1.1 sakamoto * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 1.1 sakamoto * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 1.1 sakamoto * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 1.1 sakamoto * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 1.1 sakamoto */ 32 1.1 sakamoto 33 1.1 sakamoto #define MSR_EE 0x8000 34 1.1 sakamoto 35 1.1 sakamoto .text 36 1.1 sakamoto 37 1.1 sakamoto /* 38 1.1 sakamoto * This code is loaded by the ROM loader at location 0x3100. 39 1.1 sakamoto * Move it to high memory so that it can load the kernel at 0x0000. 40 1.1 sakamoto */ 41 1.1 sakamoto #define PEF_LOAD_ADDRESS 0x3100 42 1.1 sakamoto 43 1.1 sakamoto .globl _start 44 1.1 sakamoto _start: 45 1.1 sakamoto mfmsr 3 /* Turn off interrupts */ 46 1.1 sakamoto li 4,0x3002 47 1.1 sakamoto li 4,0 48 1.1 sakamoto ori 4,4,MSR_EE 49 1.1 sakamoto andc 3,3,4 50 1.1 sakamoto mtmsr 3 51 1.1 sakamoto bl whichCPU 52 1.4 joerg cmpwi %r3,0 53 1.1 sakamoto bne 90f 54 1.1 sakamoto /* CPU 0 runs here */ 55 1.1 sakamoto /* Relocate code to final resting spot */ 56 1.1 sakamoto li 3,PEF_LOAD_ADDRESS 57 1.1 sakamoto lis 4,_start@h 58 1.1 sakamoto ori 4,4,_start@l 59 1.1 sakamoto lis 5,edata@h 60 1.1 sakamoto ori 5,5,edata@l 61 1.1 sakamoto addi 5,5,3 /* Round up - just in case */ 62 1.1 sakamoto sub 5,5,4 /* Compute # longwords to move */ 63 1.1 sakamoto srwi 5,5,2 64 1.1 sakamoto mtctr 5 65 1.1 sakamoto subi 3,3,4 /* Set up for loop */ 66 1.1 sakamoto subi 4,4,4 67 1.5 rin 0: lwzu 5,4(3) 68 1.1 sakamoto stwu 5,4(4) 69 1.5 rin bdnz 0b 70 1.1 sakamoto lis 3,start_ldr@h 71 1.1 sakamoto ori 3,3,start_ldr@l 72 1.1 sakamoto mtlr 3 /* Easiest way to do an absolute jump */ 73 1.1 sakamoto blr 74 1.1 sakamoto start_ldr: 75 1.1 sakamoto /* Clear all of BSS */ 76 1.1 sakamoto lis 3,edata@h 77 1.1 sakamoto ori 3,3,edata@l 78 1.1 sakamoto lis 4,end@h 79 1.1 sakamoto ori 4,4,end@l 80 1.1 sakamoto subi 3,3,4 81 1.1 sakamoto subi 4,4,4 82 1.1 sakamoto li 0,0 83 1.1 sakamoto 50: stwu 0,4(3) 84 1.4 joerg cmpw %r3,%r4 85 1.1 sakamoto bne 50b 86 1.1 sakamoto 90: 87 1.1 sakamoto bl main 88 1.1 sakamoto hang: 89 1.1 sakamoto b hang 90 1.1 sakamoto 91 1.1 sakamoto /* 92 1.1 sakamoto * end address 93 1.1 sakamoto */ 94 1.1 sakamoto .globl endaddr 95 1.1 sakamoto endaddr: 96 1.1 sakamoto lis 3,end@h 97 1.1 sakamoto ori 3,3,end@l 98 1.1 sakamoto lis 4,_start@h 99 1.1 sakamoto ori 4,4,_start@l 100 1.1 sakamoto sub 3,3,4 101 1.1 sakamoto blr 102 1.1 sakamoto 103 1.1 sakamoto /* 104 1.1 sakamoto * Execute 105 1.3 sakamoto * run(startsym, endsym, args, bootinfo, entry) 106 1.1 sakamoto */ 107 1.1 sakamoto .globl run 108 1.1 sakamoto run: 109 1.3 sakamoto mtctr 7 /* Entry point */ 110 1.1 sakamoto bctr 111
Indexes created Tue Sep 30 07:10:03 GMT 2025