i386/boot1u/boot.c

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 #include <libsa.h>
  27 #include <libsa/memory.h>
  28 #include <saio_types.h>
  29 #include <saio_internal.h>
  30
  31 #include <fdisk.h>
  32 #include <ufs.h>
  33
  34 #include "boot1u.h"
  35 #include "disk.h"
  36
  37 #include <io_inline.h>
  38
  39 void *gFSLoadAddress;
  40
  41 //#define BOOT_FILE "/foo"
  42 #define BOOT_FILE "/usr/standalone/i386/boot"
  43
  44
  45 //==========================================================================
  46 // Zero the BSS.
  47
  48 static void zeroBSS()
  49 {
  50     extern char _DATA__bss__begin, _DATA__bss__end;
  51     extern char _DATA__common__begin, _DATA__common__end;
  52
  53     bzero( &_DATA__bss__begin,
  54            (&_DATA__bss__end - &_DATA__bss__begin) );
  55
  56     bzero( &_DATA__common__begin,
  57            (&_DATA__common__end - &_DATA__common__begin) );
  58 }
  59
  60 struct BootVolume bv;
  61
  62 extern char chainbootdev;
  63
  64 void boot(int biosdev, void *partPtr)
  65 {
  66     struct fdisk_part part;
  67     int cc;
  68
  69     zeroBSS();
  70
  71     //    printf("Hello, world.\n");
  72
  73     // Enable A20 gate before accessing memory above 1Mb.
  74     enableA20();
  75
  76     biosdev = biosdev & 0xFF;
  77     chainbootdev = biosdev;
  78
  79     /* Don't believe the passed-in partition table */
  80     cc = findUFSPartition(biosdev, &part);
  81     if (cc<0) {
  82         printf("No UFS partition\n");
  83         halt();
  84     }
  85
  86     initUFSBVRef(&bv, biosdev, &part);
  87
  88     gFSLoadAddress = (void *)BOOT2_ADDR;
  89     cc = UFSLoadFile(&bv, BOOT_FILE);
  90     if (cc < 0) {
  91         printf("Could not load" BOOT_FILE "\n");
  92         halt();
  93     }
  94     // Return to execute booter
  95 }