xorg-server-1.4/hw/xfree86/os-support/shared/bios_devmem.c

   1 /*
   2  * Copyright 1993 by David Wexelblat <dwex@goblin.org>
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that
   7  * copyright notice and this permission notice appear in supporting
   8  * documentation, and that the name of David Wexelblat not be used in
   9  * advertising or publicity pertaining to distribution of the software without
  10  * specific, written prior permission.  David Wexelblat makes no representations
  11  * about the suitability of this software for any purpose.  It is provided
  12  * "as is" without express or implied warranty.
  13  *
  14  * DAVID WEXELBLAT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  16  * EVENT SHALL DAVID WEXELBLAT BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  20  * PERFORMANCE OF THIS SOFTWARE.
  21  *
  22  */
  23
  24 #ifdef HAVE_XORG_CONFIG_H
  25 #include <xorg-config.h>
  26 #endif
  27
  28 #include <X11/X.h>
  29 #include "xf86.h"
  30 #include "xf86Priv.h"
  31 #include "xf86_OSlib.h"
  32 #include <string.h>
  33
  34 /*
  35  * Read BIOS via /dev/mem.
  36  */
  37
  38 #ifndef DEV_MEM
  39 # define DEV_MEM "/dev/mem"
  40 #endif
  41
  42 _X_EXPORT int
  43 xf86ReadBIOS(unsigned long Base, unsigned long Offset, unsigned char *Buf,
  44                 int Len)
  45 {
  46         int fd;
  47
  48 #ifdef __ia64__
  49         if ((fd = open(DEV_MEM, O_RDONLY | O_SYNC)) < 0)
  50 #else
  51         if ((fd = open(DEV_MEM, O_RDONLY)) < 0)
  52 #endif
  53         {
  54                 xf86Msg(X_WARNING, "xf86ReadBIOS: Failed to open %s (%s)\n",
  55                         DEV_MEM, strerror(errno));
  56                 return(-1);
  57         }
  58
  59         if (lseek(fd, (Base+Offset), SEEK_SET) < 0)
  60         {
  61                 xf86Msg(X_WARNING, "xf86ReadBIOS: %s seek failed (%s)\n",
  62                         DEV_MEM, strerror(errno));
  63                 close(fd);
  64                 return(-1);
  65         }
  66         if (read(fd, Buf, Len) != Len)
  67         {
  68                 xf86Msg(X_WARNING, "xf86ReadBIOS: %s read failed (%s)\n",
  69                         DEV_MEM, strerror(errno));
  70                 close(fd);
  71                 return(-1);
  72         }
  73         close(fd);
  74         return(Len);
  75 }