xref: /freebsd/sys/powerpc/mpc85xx/ds1553_core.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/clock.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 
40 #include <machine/bus.h>
41 
42 #include <powerpc/mpc85xx/ds1553_reg.h>
43 
44 static uint8_t ds1553_direct_read(device_t, bus_size_t);
45 static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
46 
47 int
48 ds1553_attach(device_t dev)
49 {
50 	struct ds1553_softc *sc;
51 	uint8_t sec, flags;
52 
53 	sc = device_get_softc(dev);
54 
55 	if (mtx_initialized(&sc->sc_mtx) == 0) {
56 		device_printf(dev, "%s: mutex not initialized\n", __func__);
57 		return (ENXIO);
58 	}
59 
60 	if (sc->sc_read == NULL)
61 		sc->sc_read = ds1553_direct_read;
62 	if (sc->sc_write == NULL)
63 		sc->sc_write = ds1553_direct_write;
64 
65 	sc->year_offset = POSIX_BASE_YEAR;
66 
67 	mtx_lock_spin(&sc->sc_mtx);
68 
69 	/* Turn RTC on if it was not on */
70 	sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
71 	if (sec & DS1553_BIT_OSC) {
72 		sec &= ~(DS1553_BIT_OSC);
73 		(*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
74 	}
75 
76 	/* Low-battery check */
77 	flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
78 	if (flags & DS1553_BIT_BLF)
79 		device_printf(dev, "voltage-low detected.\n");
80 
81 	mtx_unlock_spin(&sc->sc_mtx);
82 
83 	return (0);
84 }
85 
86 /*
87  * Get time of day and convert it to a struct timespec.
88  * Return 0 on success, an error number otherwise.
89  */
90 int
91 ds1553_gettime(device_t dev, struct timespec *ts)
92 {
93 	struct clocktime ct;
94 	struct ds1553_softc *sc;
95 	uint8_t control;
96 
97 	sc = device_get_softc(dev);
98 
99 	mtx_lock_spin(&sc->sc_mtx);
100 
101 	control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
102 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
103 
104 	ct.nsec = 0;
105 	ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
106 	    DS1553_MASK_SECONDS);
107 	ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
108 	    DS1553_MASK_MINUTES);
109 	ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
110 	    DS1553_MASK_HOUR);
111 	ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
112 	    DS1553_MASK_DAYOFWEEK) - 1;
113 	ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
114 	    DS1553_MASK_DATE);
115 	ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
116 	    DS1553_MASK_MONTH);
117 	ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
118 
119 	control &= ~DS1553_BIT_READ;
120 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
121 
122 	ct.year += sc->year_offset;
123 
124 	mtx_unlock_spin(&sc->sc_mtx);
125 
126 	return (clock_ct_to_ts(&ct, ts));
127 }
128 
129 /*
130  * Set the time of day clock based on the value of the struct timespec arg.
131  * Return 0 on success, an error number otherwise.
132  */
133 int
134 ds1553_settime(device_t dev, struct timespec *ts)
135 {
136 	struct clocktime ct;
137 	struct ds1553_softc *sc;
138 	uint8_t control;
139 
140 	sc = device_get_softc(dev);
141 	bzero(&ct, sizeof(struct clocktime));
142 
143 	/* Accuracy is only one second. */
144 	if (ts->tv_nsec >= 500000000)
145 		ts->tv_sec++;
146 	ts->tv_nsec = 0;
147 	clock_ts_to_ct(ts, &ct);
148 
149 	ct.year -= sc->year_offset;
150 
151 	mtx_lock_spin(&sc->sc_mtx);
152 
153 	/* Halt updates to external registers */
154 	control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
155 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
156 
157 	(*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
158 	    DS1553_MASK_SECONDS);
159 	(*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
160 	    DS1553_MASK_MINUTES);
161 	(*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
162 	    DS1553_MASK_HOUR);
163 	(*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
164 	    DS1553_MASK_DAYOFWEEK);
165 	(*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
166 	    DS1553_MASK_DATE);
167 	(*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
168 	    DS1553_MASK_MONTH);
169 	(*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
170 
171 	/* Resume updates to external registers */
172 	control &= ~DS1553_BIT_WRITE;
173 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
174 
175 	mtx_unlock_spin(&sc->sc_mtx);
176 
177 	return (0);
178 }
179 
180 static uint8_t
181 ds1553_direct_read(device_t dev, bus_size_t off)
182 {
183 	struct ds1553_softc *sc;
184 
185 	sc = device_get_softc(dev);
186 	return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
187 }
188 
189 static void
190 ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
191 {
192 	struct ds1553_softc *sc;
193 
194 	sc = device_get_softc(dev);
195 	bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
196 }
197