sys/arch/i386/stand/lib/getextmemx.c

   1 /*      $NetBSD: getextmemx.c,v 1.10 2011/06/16 13:27:59 joerg Exp $    */
   2
   3 /*
   4  * Copyright (c) 1997, 1999
   5  *      Matthias Drochner.  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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  *
  27  */
  28
  29 /*
  30  * Try 2 more fancy BIOS calls to get the size of extended
  31  * memory besides the classical int15/88, take maximum.
  32  * needs lowlevel parts from biosmemx.S and biosmem.S
  33  */
  34
  35 #include <lib/libsa/stand.h>
  36 #include "libi386.h"
  37
  38 int
  39 getextmemx(void)
  40 {
  41         int buf[5], i;
  42         int extmem = getextmem1();
  43 #ifdef SUPPORT_PS2
  44         struct {
  45                 uint16_t len;
  46                 uint32_t dta[8];
  47                 /* pad to 64 bytes - without this, machine would reset */
  48                 uint8_t __pad[30];
  49         } __packed bufps2;
  50 #endif
  51
  52 #ifdef DEBUG_MEMSIZE
  53         printf("extmem1: %xk\n", extmem);
  54 #endif
  55         if (!getextmem2(buf)) {
  56 #ifdef DEBUG_MEMSIZE
  57                 printf("extmem2: %xk + %xk\n", buf[0], buf[1] * 64);
  58 #endif
  59                 if (buf[0] <= 15 * 1024) {
  60                         int help = buf[0];
  61                         if (help == 15 * 1024)
  62                                 help += buf[1] * 64;
  63                         if (extmem < help)
  64                                 extmem = help;
  65                 }
  66         }
  67
  68         i = 0;
  69         do {
  70                 if (getmementry(&i, buf))
  71                         break;
  72 #ifdef DEBUG_MEMSIZE
  73                 printf("mementry: (%d) %x %x %x %x %x\n",
  74                         i, buf[0], buf[1], buf[2], buf[3], buf[4]);
  75 #endif
  76                 if ((buf[4] == 1 && buf[0] == 0x100000)
  77                     && extmem < buf[2] / 1024)
  78                         extmem = buf[2] / 1024;
  79         } while (i);
  80
  81 #ifdef SUPPORT_PS2
  82         /* use local memory information from RETURN MEMORY-MAP INFORMATION */
  83         if (!getextmemps2((void *) &bufps2)) {
  84                 int help = bufps2.dta[0];
  85                 if (help == 15 * 1024)
  86                         help += bufps2.dta[1];
  87                 if (extmem < help)
  88                         extmem = help;
  89         }
  90 #endif
  91
  92         return extmem;
  93 }