xref: /openbsd-src/sys/dev/isa/elink.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: elink.c,v 1.5 1997/11/07 08:06:45 niklas Exp $	*/
2 /*	$NetBSD: elink.c,v 1.9 1996/05/03 19:06:27 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1996 Jason R. Thorpe.  All rights reserved.
6  * Copyright (c) 1994, 1995 Charles Hannum.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Charles Hannum.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Common code for dealing with 3COM ethernet cards.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/queue.h>
42 
43 #include <machine/bus.h>
44 
45 #include <dev/isa/elink.h>
46 
47 /*
48  * This list keeps track of which ISAs have gotten an elink_reset().
49  */
50 struct elink_done_reset {
51 	LIST_ENTRY(elink_done_reset)	er_link;
52 	int				er_bus;
53 };
54 static LIST_HEAD(, elink_done_reset) elink_all_resets;
55 static int elink_all_resets_initialized;
56 
57 /*
58  * Issue a `global reset' to all cards, and reset the ID state machines.  We
59  * have to be careful to do the global reset only once during autoconfig, to
60  * prevent resetting boards that have already been configured.
61  *
62  * The "bus" argument here is the unit number of the ISA bus, e.g. "0"
63  * if the bus is "isa0".
64  *
65  * NOTE: the caller MUST provide an i/o handle for ELINK_ID_PORT!
66  */
67 void
68 elink_reset(iot, ioh, bus)
69 	bus_space_tag_t iot;
70 	bus_space_handle_t ioh;
71 	int bus;
72 {
73 	struct elink_done_reset *er;
74 
75 	if (elink_all_resets_initialized == 0) {
76 		LIST_INIT(&elink_all_resets);
77 		elink_all_resets_initialized = 1;
78 	}
79 
80 	/*
81 	 * Reset these cards if we haven't done so already.
82 	 */
83 	for (er = elink_all_resets.lh_first; er != NULL;
84 	    er = er->er_link.le_next)
85 		if (er->er_bus == bus)
86 			goto out;
87 
88 	/* Mark this bus so we don't do it again. */
89 	er = (struct elink_done_reset *)malloc(sizeof(struct elink_done_reset),
90 	    M_DEVBUF, M_NOWAIT);
91 	if (er == NULL)
92 		panic("elink_reset: can't allocate state storage");
93 
94 	er->er_bus = bus;
95 	LIST_INSERT_HEAD(&elink_all_resets, er, er_link);
96 
97 	/* Haven't reset the cards on this bus, yet. */
98 	bus_space_write_1(iot, ioh, 0, ELINK_RESET);
99 
100  out:
101 	bus_space_write_1(iot, ioh, 0, 0x00);
102 	bus_space_write_1(iot, ioh, 0, 0x00);
103 }
104 
105 /*
106  * The `ID sequence' is really just snapshots of an 8-bit CRC register as 0
107  * bits are shifted in.  Different board types use different polynomials.
108  *
109  * NOTE: the caller MUST provide an i/o handle for ELINK_ID_PORT!
110  */
111 void
112 elink_idseq(iot, ioh, p)
113 	bus_space_tag_t iot;
114 	bus_space_handle_t ioh;
115 	register u_char p;
116 {
117 	register int i;
118 	register u_char c;
119 
120 	c = 0xff;
121 	for (i = 255; i; i--) {
122 		bus_space_write_1(iot, ioh, 0, c);
123 		if (c & 0x80) {
124 			c <<= 1;
125 			c ^= p;
126 		} else
127 			c <<= 1;
128 	}
129 }
130