sys/arch/bebox/stand/boot/srt0.s

   1 /*      $NetBSD: srt0.s,v 1.2 1999/02/15 04:38:06 sakamoto Exp $        */
   2
   3 /*-
   4  * Copyright (C) 1995-1997 Gary Thomas (gdt@linuxppc.org)
   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 Gary Thomas.
  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
  33 #define MSR_EE  0x8000
  34
  35         .text
  36
  37 /*
  38  * This code is loaded by the ROM loader at location 0x3100.
  39  * Move it to high memory so that it can load the kernel at 0x0000.
  40  */
  41 #define PEF_LOAD_ADDRESS        0x3100
  42
  43         .globl  _start
  44 _start:
  45         mfmsr   3               /* Turn off interrupts */
  46         li      4,0x3002
  47         li      4,0
  48         ori     4,4,MSR_EE
  49         andc    3,3,4
  50         mtmsr   3
  51         bl      whichCPU
  52         cmpi    0,3,0
  53         bne     90f
  54 /* CPU 0 runs here */
  55 /* Relocate code to final resting spot */
  56         li      3,PEF_LOAD_ADDRESS
  57         lis     4,_start@h
  58         ori     4,4,_start@l
  59         lis     5,edata@h
  60         ori     5,5,edata@l
  61         addi    5,5,3                   /* Round up - just in case */
  62         sub     5,5,4                   /* Compute # longwords to move */
  63         srwi    5,5,2
  64         mtctr   5
  65         subi    3,3,4                   /* Set up for loop */
  66         subi    4,4,4
  67 00:     lwzu    5,4(3)
  68         stwu    5,4(4)
  69         bdnz    00b
  70         lis     3,start_ldr@h
  71         ori     3,3,start_ldr@l
  72         mtlr    3                       /* Easiest way to do an absolute jump */
  73         blr
  74 start_ldr:
  75 /* Clear all of BSS */
  76         lis     3,edata@h
  77         ori     3,3,edata@l
  78         lis     4,end@h
  79         ori     4,4,end@l
  80         subi    3,3,4
  81         subi    4,4,4
  82         li      0,0
  83 50:     stwu    0,4(3)
  84         cmp     0,3,4
  85         bne     50b
  86 90:
  87         bl      main
  88 hang:
  89         b       hang
  90
  91 /*
  92  * end address
  93  */
  94         .globl endaddr
  95 endaddr:
  96         lis     3,end@h
  97         ori     3,3,end@l
  98         lis     4,_start@h
  99         ori     4,4,_start@l
 100         sub     3,3,4
 101         blr
 102
 103 /*
 104  * Execute
 105  * run(startsym, endsym, args, bootinfo, entry)
 106  */
 107         .globl  run
 108 run:
 109         mtctr   7                       /* Entry point */
 110         bctr