LXR linux/arch/x86/boot/voyager.c

   1/* -*- linux-c -*- ------------------------------------------------------- *
   2 *
   3 *   Copyright (C) 1991, 1992 Linus Torvalds
   4 *   Copyright 2007 rPath, Inc. - All Rights Reserved
   5 *
   6 *   This file is part of the Linux kernel, and is made available under
   7 *   the terms of the GNU General Public License version 2.
   8 *
   9 * ----------------------------------------------------------------------- */
  10
  11/*
  12 * Get the Voyager config information
  13 */
  14
  15#include "boot.h"
  16
  17int query_voyager(void)
  18{
  19        u8 err;
  20        u16 es, di;
  21        /* Abuse the apm_bios_info area for this */
  22        u8 *data_ptr = (u8 *)&boot_params.apm_bios_info;
  23
  24        data_ptr[0] = 0xff;     /* Flag on config not found(?) */
  25
  26        asm("pushw %%es ; "
  27            "int $0x15 ; "
  28            "setc %0 ; "
  29            "movw %%es, %1 ; "
  30            "popw %%es"
  31            : "=q" (err), "=r" (es), "=D" (di)
  32            : "a" (0xffc0));
  33
  34        if (err)
  35                return -1;      /* Not Voyager */
  36
  37        set_fs(es);
  38        copy_from_fs(data_ptr, di, 7);  /* Table is 7 bytes apparently */
  39        return 0;
  40}
  41