/* $NetBSD: srt0.s,v 1.4 2014/08/06 15:23:07 joerg Exp $ */ /*- * Copyright (C) 1995-1997 Gary Thomas (gdt@linuxppc.org) * 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 Gary Thomas. * 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. */ #define MSR_EE 0x8000 .text /* * This code is loaded by the ROM loader at location 0x3100. * Move it to high memory so that it can load the kernel at 0x0000. */ #define PEF_LOAD_ADDRESS 0x3100 .globl _start _start: mfmsr 3 /* Turn off interrupts */ li 4,0x3002 li 4,0 ori 4,4,MSR_EE andc 3,3,4 mtmsr 3 bl whichCPU cmpwi %r3,0 bne 90f /* CPU 0 runs here */ /* Relocate code to final resting spot */ li 3,PEF_LOAD_ADDRESS lis 4,_start@h ori 4,4,_start@l lis 5,edata@h ori 5,5,edata@l addi 5,5,3 /* Round up - just in case */ sub 5,5,4 /* Compute # longwords to move */ srwi 5,5,2 mtctr 5 subi 3,3,4 /* Set up for loop */ subi 4,4,4 00: lwzu 5,4(3) stwu 5,4(4) bdnz 00b lis 3,start_ldr@h ori 3,3,start_ldr@l mtlr 3 /* Easiest way to do an absolute jump */ blr start_ldr: /* Clear all of BSS */ lis 3,edata@h ori 3,3,edata@l lis 4,end@h ori 4,4,end@l subi 3,3,4 subi 4,4,4 li 0,0 50: stwu 0,4(3) cmpw %r3,%r4 bne 50b 90: bl main hang: b hang /* * end address */ .globl endaddr endaddr: lis 3,end@h ori 3,3,end@l lis 4,_start@h ori 4,4,_start@l sub 3,3,4 blr /* * Execute * run(startsym, endsym, args, bootinfo, entry) */ .globl run run: mtctr 7 /* Entry point */ bctr