sys/dev/netif/elink_layer/elink.c

   1 /*
   2  * Copyright (c) 1994 Charles Hannum.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  * 3. All advertising materials mentioning features or use of this software
  13  *    must display the following acknowledgement:
  14  *      This product includes software developed by Charles Hannum.
  15  * 4. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sys/i386/isa/elink.c,v 1.10 1999/08/28 00:44:41 peter Exp $
  30  * $DragonFly: src/sys/dev/netif/elink_layer/elink.c,v 1.5 2006/08/06 12:49:05 swildner Exp $
  31  */
  32
  33 /*
  34  * Common code for dealing with 3COM ethernet cards.
  35  */
  36
  37 #include <sys/types.h>
  38
  39 #include <machine/cpufunc.h>
  40
  41 #include "elink.h"
  42
  43 /*
  44  * Issue a `global reset' to all cards.  We have to be careful to do this only
  45  * once during autoconfig, to prevent resetting boards that have already been
  46  * configured.
  47  */
  48 void
  49 elink_reset(void)
  50 {
  51         static int x = 0;
  52
  53         if (x == 0) {
  54                 x = 1;
  55                 outb(ELINK_ID_PORT, ELINK_RESET);
  56         }
  57 }
  58
  59 /*
  60  * The `ID sequence' is really just snapshots of an 8-bit CRC register as 0
  61  * bits are shifted in.  Different board types use different polynomials.
  62  */
  63 void
  64 elink_idseq(u_char p)
  65 {
  66         int i;
  67         u_char c;
  68
  69         c = 0xff;
  70         for (i = 255; i; i--) {
  71                 outb(ELINK_ID_PORT, c);
  72                 if (c & 0x80) {
  73                         c <<= 1;
  74                         c ^= p;
  75                 } else
  76                         c <<= 1;
  77         }
  78 }