cmos.c revision 1.3 
1/*	$NetBSD: cmos.c,v 1.3 2008/05/31 07:30:45 taca Exp $	*/
2
3/*
4 * Copyright (C) 2003 JONE System Co., Inc.
5 * All right reserved.
6 *
7 * Copyright (C) 1999, 2000, 2001, 2002 JEPRO Co., Ltd.
8 * All right reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 */
33/*
34 * Copyright (c) 2007 David Young.  All right reserved.
35 *
36 * Redistribution and use in source and binary forms, with or
37 * without modification, are permitted provided that the following
38 * conditions are met:
39 *
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above
43 *    copyright notice, this list of conditions and the following
44 *    disclaimer in the documentation and/or other materials provided
45 *    with the distribution.
46 * 3. The name of David Young may not be used to endorse or promote
47 *    products derived from this software without specific prior
48 *    written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
51 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
52 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
53 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
55 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
56 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
57 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
58 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
60 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 */
63
64#include <sys/cdefs.h>
65__KERNEL_RCSID(0, "$NetBSD: cmos.c,v 1.3 2008/05/31 07:30:45 taca Exp $");
66
67#include <sys/param.h>
68#include <sys/systm.h>
69#include <sys/kernel.h>
70#include <sys/malloc.h>
71#include <sys/ioctl.h>
72#include <sys/proc.h>
73#include <sys/device.h>
74#include <sys/conf.h>
75#include <sys/kauth.h>
76
77#include <machine/bus.h>
78#include <machine/intr.h>
79
80#include <dev/isa/isareg.h>
81#include <dev/isa/isavar.h>
82#include <dev/ic/mc146818reg.h>
83#include <i386/isa/nvram.h>
84
85#define	CMOS_SUM	32
86#define	CMOS_BIOSSPEC	34	/* start of BIOS-specific configuration data */
87
88#define	NVRAM_SUM	(MC_NVRAM_START + CMOS_SUM)
89#define	NVRAM_BIOSSPEC	(MC_NVRAM_START + CMOS_BIOSSPEC)
90
91#define	CMOS_SIZE	NVRAM_BIOSSPEC
92
93struct cmos_softc {			/* driver status information */
94	int	sc_open;
95	uint8_t	sc_buf[CMOS_SIZE];
96} cmos_softc;
97
98#ifdef CMOS_DEBUG
99int cmos_debug = 0;
100#endif
101
102void cmosattach(int);
103dev_type_open(cmos_open);
104dev_type_close(cmos_close);
105dev_type_read(cmos_read);
106dev_type_write(cmos_write);
107
108static void cmos_sum(uint8_t *, int, int, int);
109#ifdef CMOS_DEBUG
110static void cmos_dump(uint8_t *);
111#endif
112
113const struct cdevsw cmos_cdevsw = {
114	.d_open = cmos_open, .d_close = cmos_close, .d_read = cmos_read,
115	.d_write = cmos_write, .d_ioctl = noioctl,
116	.d_stop = nostop, .d_tty = notty, .d_poll = nopoll, .d_mmap = nommap,
117	.d_kqfilter = nokqfilter,
118};
119
120void
121cmosattach(int n)
122{
123	printf("cmos: attached.\n");
124}
125
126int
127cmos_open(dev_t dev, int flags, int ifmt, struct lwp *l)
128{
129	struct cmos_softc *sc = &cmos_softc;
130	struct proc *p = l->l_proc;
131	int error;
132
133	error = kauth_authorize_generic(p->p_cred, KAUTH_GENERIC_ISSUSER,
134	    &p->p_acflag);
135
136	if (error != 0)
137		return error;
138
139	sc->sc_open = 1;
140#ifdef CMOS_DEBUG
141	printf("cmos: opened\n");
142#endif
143	return 0;
144}
145
146int
147cmos_close(dev_t dev, int flags, int ifmt, struct lwp *l)
148{
149	struct cmos_softc *sc = &cmos_softc;
150
151	sc->sc_open = 0;
152#ifdef CMOS_DEBUG
153	printf("cmos: closed\n");
154#endif
155	return 0;
156}
157
158static void
159cmos_fetch(struct cmos_softc *sc)
160{
161	int i, s;
162	uint8_t *p;
163
164	p = sc->sc_buf;
165
166	s = splclock();
167	for (i = 0; i < CMOS_SIZE; i++)
168		*p++ = mc146818_read(sc, i);
169	splx(s);
170}
171
172int
173cmos_read(dev_t dev, struct uio *uio, int ioflag)
174{
175	struct cmos_softc *sc = &cmos_softc;
176
177	if (uio->uio_resid > CMOS_SIZE)
178		return EINVAL;
179
180#ifdef CMOS_DEBUG
181	printf("cmos: try to read to %d\n", CMOS_SIZE);
182#endif
183	cmos_fetch(sc);
184
185	return uiomove(sc->sc_buf, CMOS_SIZE, uio);
186}
187
188int
189cmos_write(dev_t dev, struct uio *uio, int ioflag)
190{
191	struct cmos_softc *sc = &cmos_softc;
192	int error = 0, i, s;
193
194	cmos_fetch(sc);
195
196	error = uiomove(sc->sc_buf, CMOS_SIZE, uio);
197#ifdef CMOS_DEBUG
198	printf("write %d\n", l);
199	if (cmos_debug)
200		cmos_dump(sc->sc_buf);
201#endif
202	if (error)
203		return error;
204
205	cmos_sum(sc->sc_buf, NVRAM_DISKETTE, NVRAM_SUM, NVRAM_SUM);
206
207#ifdef CMOS_DEBUG
208	if (cmos_debug)
209		cmos_dump(sc->sc_buf);
210#endif
211	s = splclock();
212	for (i = NVRAM_DISKETTE; i < CMOS_SIZE; i++)
213		mc146818_write(sc, i, sc->sc_buf[i]);
214	splx(s);
215
216	return error;
217}
218
219static void
220cmos_sum(uint8_t *p, int from, int to, int offset)
221{
222	int i;
223	uint16_t sum;
224
225#ifdef CMOS_DEBUG
226	printf("%s: from %d to %d and store %d\n", __func__, from, to, offset);
227#endif
228
229	sum = 0;
230	for (i = from; i < to; i++)
231		sum += p[i];
232	p[offset] = sum >> 8;
233	p[offset + 1] = sum & 0xff;
234}
235
236#ifdef CMOS_DEBUG
237static void
238cmos_dump(uint8_t *p)
239{
240	int i;
241
242	for (i = 0; i < CMOS_SIZE; i++) {
243		if (i % 16 == 0)
244			printf("%02x:", i);
245		printf(" %02x", p[i]);
246		if (i % 16 == 15)
247			printf("\n", buf);
248	}
249	printf("\n");
250}
251#endif
252