1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (C) 2006-2008 Semihalf, Grzegorz Bernacki
5 * 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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/clock.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36
37 #include <machine/bus.h>
38
39 #include <powerpc/mpc85xx/ds1553_reg.h>
40
41 static uint8_t ds1553_direct_read(device_t, bus_size_t);
42 static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
43
44 int
ds1553_attach(device_t dev)45 ds1553_attach(device_t dev)
46 {
47 struct ds1553_softc *sc;
48 uint8_t sec, flags;
49
50 sc = device_get_softc(dev);
51
52 if (mtx_initialized(&sc->sc_mtx) == 0) {
53 device_printf(dev, "%s: mutex not initialized\n", __func__);
54 return (ENXIO);
55 }
56
57 if (sc->sc_read == NULL)
58 sc->sc_read = ds1553_direct_read;
59 if (sc->sc_write == NULL)
60 sc->sc_write = ds1553_direct_write;
61
62 sc->year_offset = POSIX_BASE_YEAR;
63
64 mtx_lock_spin(&sc->sc_mtx);
65
66 /* Turn RTC on if it was not on */
67 sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
68 if (sec & DS1553_BIT_OSC) {
69 sec &= ~(DS1553_BIT_OSC);
70 (*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
71 }
72
73 /* Low-battery check */
74 flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
75 if (flags & DS1553_BIT_BLF)
76 device_printf(dev, "voltage-low detected.\n");
77
78 mtx_unlock_spin(&sc->sc_mtx);
79
80 return (0);
81 }
82
83 /*
84 * Get time of day and convert it to a struct timespec.
85 * Return 0 on success, an error number otherwise.
86 */
87 int
ds1553_gettime(device_t dev,struct timespec * ts)88 ds1553_gettime(device_t dev, struct timespec *ts)
89 {
90 struct clocktime ct;
91 struct ds1553_softc *sc;
92 uint8_t control;
93
94 sc = device_get_softc(dev);
95
96 mtx_lock_spin(&sc->sc_mtx);
97
98 control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
99 (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
100
101 ct.nsec = 0;
102 ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
103 DS1553_MASK_SECONDS);
104 ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
105 DS1553_MASK_MINUTES);
106 ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
107 DS1553_MASK_HOUR);
108 ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
109 DS1553_MASK_DAYOFWEEK) - 1;
110 ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
111 DS1553_MASK_DATE);
112 ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
113 DS1553_MASK_MONTH);
114 ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
115
116 control &= ~DS1553_BIT_READ;
117 (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
118
119 ct.year += sc->year_offset;
120
121 mtx_unlock_spin(&sc->sc_mtx);
122
123 return (clock_ct_to_ts(&ct, ts));
124 }
125
126 /*
127 * Set the time of day clock based on the value of the struct timespec arg.
128 * Return 0 on success, an error number otherwise.
129 */
130 int
ds1553_settime(device_t dev,struct timespec * ts)131 ds1553_settime(device_t dev, struct timespec *ts)
132 {
133 struct clocktime ct;
134 struct ds1553_softc *sc;
135 uint8_t control;
136
137 sc = device_get_softc(dev);
138 bzero(&ct, sizeof(struct clocktime));
139
140 /* Accuracy is only one second. */
141 if (ts->tv_nsec >= 500000000)
142 ts->tv_sec++;
143 ts->tv_nsec = 0;
144 clock_ts_to_ct(ts, &ct);
145
146 ct.year -= sc->year_offset;
147
148 mtx_lock_spin(&sc->sc_mtx);
149
150 /* Halt updates to external registers */
151 control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
152 (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
153
154 (*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
155 DS1553_MASK_SECONDS);
156 (*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
157 DS1553_MASK_MINUTES);
158 (*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
159 DS1553_MASK_HOUR);
160 (*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
161 DS1553_MASK_DAYOFWEEK);
162 (*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
163 DS1553_MASK_DATE);
164 (*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
165 DS1553_MASK_MONTH);
166 (*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
167
168 /* Resume updates to external registers */
169 control &= ~DS1553_BIT_WRITE;
170 (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
171
172 mtx_unlock_spin(&sc->sc_mtx);
173
174 return (0);
175 }
176
177 static uint8_t
ds1553_direct_read(device_t dev,bus_size_t off)178 ds1553_direct_read(device_t dev, bus_size_t off)
179 {
180 struct ds1553_softc *sc;
181
182 sc = device_get_softc(dev);
183 return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
184 }
185
186 static void
ds1553_direct_write(device_t dev,bus_size_t off,uint8_t val)187 ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
188 {
189 struct ds1553_softc *sc;
190
191 sc = device_get_softc(dev);
192 bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
193 }
194