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

   1 /*      $NetBSD: getextmemx.c,v 1.8 2007/12/25 18:33:34 perry 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 extern int getextmem2(int *);
  39 extern int getmementry(int *, int *);
  40 extern int getextmemps2(void *);
  41
  42 int
  43 getextmemx(void)
  44 {
  45         int buf[5], i;
  46         int extmem = getextmem1();
  47 #ifdef SUPPORT_PS2
  48         struct {
  49                 uint16_t len;
  50                 uint32_t dta[8];
  51                 /* pad to 64 bytes - without this, machine would reset */
  52                 uint8_t __pad[30];
  53         } __packed bufps2;
  54 #endif
  55
  56 #ifdef DEBUG_MEMSIZE
  57         printf("extmem1: %xk\n", extmem);
  58 #endif
  59         if (!getextmem2(buf)) {
  60 #ifdef DEBUG_MEMSIZE
  61                 printf("extmem2: %xk + %xk\n", buf[0], buf[1] * 64);
  62 #endif
  63                 if (buf[0] <= 15 * 1024) {
  64                         int help = buf[0];
  65                         if (help == 15 * 1024)
  66                                 help += buf[1] * 64;
  67                         if (extmem < help)
  68                                 extmem = help;
  69                 }
  70         }
  71
  72         i = 0;
  73         do {
  74                 if (getmementry(&i, buf))
  75                         break;
  76 #ifdef DEBUG_MEMSIZE
  77                 printf("mementry: (%d) %x %x %x %x %x\n",
  78                         i, buf[0], buf[1], buf[2], buf[3], buf[4]);
  79 #endif
  80                 if ((buf[4] == 1 && buf[0] == 0x100000)
  81                     && extmem < buf[2] / 1024)
  82                         extmem = buf[2] / 1024;
  83         } while (i);
  84
  85 #ifdef SUPPORT_PS2
  86         /* use local memory information from RETURN MEMORY-MAP INFORMATION */
  87         if (!getextmemps2((void *) &bufps2)) {
  88                 int help = bufps2.dta[0];
  89                 if (help == 15 * 1024)
  90                         help += bufps2.dta[1];
  91                 if (extmem < help)
  92                         extmem = help;
  93         }
  94 #endif
  95
  96         return extmem;
  97 }