xref: /freebsd/sys/powerpc/mpc85xx/ds1553_core.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
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/cdefs.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/clock.h>
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 
38 #include <machine/bus.h>
39 
40 #include <powerpc/mpc85xx/ds1553_reg.h>
41 
42 static uint8_t ds1553_direct_read(device_t, bus_size_t);
43 static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
44 
45 int
46 ds1553_attach(device_t dev)
47 {
48 	struct ds1553_softc *sc;
49 	uint8_t sec, flags;
50 
51 	sc = device_get_softc(dev);
52 
53 	if (mtx_initialized(&sc->sc_mtx) == 0) {
54 		device_printf(dev, "%s: mutex not initialized\n", __func__);
55 		return (ENXIO);
56 	}
57 
58 	if (sc->sc_read == NULL)
59 		sc->sc_read = ds1553_direct_read;
60 	if (sc->sc_write == NULL)
61 		sc->sc_write = ds1553_direct_write;
62 
63 	sc->year_offset = POSIX_BASE_YEAR;
64 
65 	mtx_lock_spin(&sc->sc_mtx);
66 
67 	/* Turn RTC on if it was not on */
68 	sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
69 	if (sec & DS1553_BIT_OSC) {
70 		sec &= ~(DS1553_BIT_OSC);
71 		(*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
72 	}
73 
74 	/* Low-battery check */
75 	flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
76 	if (flags & DS1553_BIT_BLF)
77 		device_printf(dev, "voltage-low detected.\n");
78 
79 	mtx_unlock_spin(&sc->sc_mtx);
80 
81 	return (0);
82 }
83 
84 /*
85  * Get time of day and convert it to a struct timespec.
86  * Return 0 on success, an error number otherwise.
87  */
88 int
89 ds1553_gettime(device_t dev, struct timespec *ts)
90 {
91 	struct clocktime ct;
92 	struct ds1553_softc *sc;
93 	uint8_t control;
94 
95 	sc = device_get_softc(dev);
96 
97 	mtx_lock_spin(&sc->sc_mtx);
98 
99 	control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
100 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
101 
102 	ct.nsec = 0;
103 	ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
104 	    DS1553_MASK_SECONDS);
105 	ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
106 	    DS1553_MASK_MINUTES);
107 	ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
108 	    DS1553_MASK_HOUR);
109 	ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
110 	    DS1553_MASK_DAYOFWEEK) - 1;
111 	ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
112 	    DS1553_MASK_DATE);
113 	ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
114 	    DS1553_MASK_MONTH);
115 	ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
116 
117 	control &= ~DS1553_BIT_READ;
118 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
119 
120 	ct.year += sc->year_offset;
121 
122 	mtx_unlock_spin(&sc->sc_mtx);
123 
124 	return (clock_ct_to_ts(&ct, ts));
125 }
126 
127 /*
128  * Set the time of day clock based on the value of the struct timespec arg.
129  * Return 0 on success, an error number otherwise.
130  */
131 int
132 ds1553_settime(device_t dev, struct timespec *ts)
133 {
134 	struct clocktime ct;
135 	struct ds1553_softc *sc;
136 	uint8_t control;
137 
138 	sc = device_get_softc(dev);
139 	bzero(&ct, sizeof(struct clocktime));
140 
141 	/* Accuracy is only one second. */
142 	if (ts->tv_nsec >= 500000000)
143 		ts->tv_sec++;
144 	ts->tv_nsec = 0;
145 	clock_ts_to_ct(ts, &ct);
146 
147 	ct.year -= sc->year_offset;
148 
149 	mtx_lock_spin(&sc->sc_mtx);
150 
151 	/* Halt updates to external registers */
152 	control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
153 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
154 
155 	(*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
156 	    DS1553_MASK_SECONDS);
157 	(*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
158 	    DS1553_MASK_MINUTES);
159 	(*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
160 	    DS1553_MASK_HOUR);
161 	(*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
162 	    DS1553_MASK_DAYOFWEEK);
163 	(*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
164 	    DS1553_MASK_DATE);
165 	(*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
166 	    DS1553_MASK_MONTH);
167 	(*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
168 
169 	/* Resume updates to external registers */
170 	control &= ~DS1553_BIT_WRITE;
171 	(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
172 
173 	mtx_unlock_spin(&sc->sc_mtx);
174 
175 	return (0);
176 }
177 
178 static uint8_t
179 ds1553_direct_read(device_t dev, bus_size_t off)
180 {
181 	struct ds1553_softc *sc;
182 
183 	sc = device_get_softc(dev);
184 	return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
185 }
186 
187 static void
188 ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
189 {
190 	struct ds1553_softc *sc;
191 
192 	sc = device_get_softc(dev);
193 	bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
194 }
195