xref: /freebsd/sys/powerpc/mpc85xx/ds1553_core.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
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
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
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
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
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
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