xref: /netbsd-src/sys/dev/isa/elink.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: elink.c,v 1.10 1996/10/21 22:40:39 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1996 Jason R. Thorpe.  All rights reserved.
5  * Copyright (c) 1994, 1995 Charles Hannum.  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  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Charles Hannum.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Common code for dealing with 3COM ethernet cards.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
40 #include <sys/queue.h>
41 
42 #include <machine/bus.h>
43 
44 #include <dev/isa/elink.h>
45 
46 /*
47  * This list keeps track of which ISAs have gotten an elink_reset().
48  */
49 struct elink_done_reset {
50 	LIST_ENTRY(elink_done_reset)	er_link;
51 	int				er_bus;
52 };
53 static LIST_HEAD(, elink_done_reset) elink_all_resets;
54 static int elink_all_resets_initialized;
55 
56 /*
57  * Issue a `global reset' to all cards, and reset the ID state machines.  We
58  * have to be careful to do the global reset only once during autoconfig, to
59  * prevent resetting boards that have already been configured.
60  *
61  * The "bus" argument here is the unit number of the ISA bus, e.g. "0"
62  * if the bus is "isa0".
63  *
64  * NOTE: the caller MUST provide an access handle for ELINK_ID_PORT!
65  */
66 void
67 elink_reset(iot, ioh, bus)
68 	bus_space_tag_t iot;
69 	bus_space_handle_t ioh;
70 	int bus;
71 {
72 	struct elink_done_reset *er;
73 
74 	if (elink_all_resets_initialized == 0) {
75 		LIST_INIT(&elink_all_resets);
76 		elink_all_resets_initialized = 1;
77 	}
78 
79 	/*
80 	 * Reset these cards if we haven't done so already.
81 	 */
82 	for (er = elink_all_resets.lh_first; er != NULL;
83 	    er = er->er_link.le_next)
84 		if (er->er_bus == bus)
85 			goto out;
86 
87 	/* Mark this bus so we don't do it again. */
88 	er = (struct elink_done_reset *)malloc(sizeof(struct elink_done_reset),
89 	    M_DEVBUF, M_NOWAIT);
90 	if (er == NULL)
91 		panic("elink_reset: can't allocate state storage");
92 
93 	er->er_bus = bus;
94 	LIST_INSERT_HEAD(&elink_all_resets, er, er_link);
95 
96 	/* Haven't reset the cards on this bus, yet. */
97 	bus_space_write_1(iot, ioh, 0, ELINK_RESET);
98 
99  out:
100 	bus_space_write_1(iot, ioh, 0, 0x00);
101 	bus_space_write_1(iot, ioh, 0, 0x00);
102 }
103 
104 /*
105  * The `ID sequence' is really just snapshots of an 8-bit CRC register as 0
106  * bits are shifted in.  Different board types use different polynomials.
107  *
108  * NOTE: the caller MUST provide an access handle for ELINK_ID_PORT!
109  */
110 void
111 elink_idseq(iot, ioh, p)
112 	bus_space_tag_t iot;
113 	bus_space_handle_t ioh;
114 	register u_char p;
115 {
116 	register int i;
117 	register u_char c;
118 
119 	c = 0xff;
120 	for (i = 255; i; i--) {
121 		bus_space_write_1(iot, ioh, 0, c);
122 		if (c & 0x80) {
123 			c <<= 1;
124 			c ^= p;
125 		} else
126 			c <<= 1;
127 	}
128 }
129