rtc.c revision 266152 
1/*-
2 * Copyright (C) 2008 MARVELL INTERNATIONAL LTD.
3 * All rights reserved.
4 *
5 * Developed by Semihalf.
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 * 3. Neither the name of MARVELL nor the names of contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: stable/10/sys/arm/mv/rtc.c 266152 2014-05-15 16:11:06Z ian $");
34#include <sys/param.h>
35#include <sys/bus.h>
36#include <sys/lock.h>
37#include <sys/time.h>
38#include <sys/clock.h>
39#include <sys/resource.h>
40#include <sys/systm.h>
41#include <sys/rman.h>
42#include <sys/kernel.h>
43#include <sys/module.h>
44
45#include <machine/bus.h>
46#include <machine/resource.h>
47
48#include <dev/ofw/ofw_bus.h>
49#include <dev/ofw/ofw_bus_subr.h>
50
51#include "clock_if.h"
52
53#define MV_RTC_TIME_REG		0x00
54#define MV_RTC_DATE_REG		0x04
55#define YEAR_BASE		2000
56
57struct mv_rtc_softc {
58	device_t dev;
59	struct resource *res[1];
60};
61
62static struct resource_spec res_spec[] = {
63	{ SYS_RES_MEMORY, 0, RF_ACTIVE },
64	{ -1, 0 }
65};
66
67static int mv_rtc_probe(device_t dev);
68static int mv_rtc_attach(device_t dev);
69
70static int mv_rtc_gettime(device_t dev, struct timespec *ts);
71static int mv_rtc_settime(device_t dev, struct timespec *ts);
72
73static uint32_t mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off);
74static int mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off,
75    uint32_t val);
76
77static device_method_t mv_rtc_methods[] = {
78	DEVMETHOD(device_probe,		mv_rtc_probe),
79	DEVMETHOD(device_attach,	mv_rtc_attach),
80
81	DEVMETHOD(clock_gettime,	mv_rtc_gettime),
82	DEVMETHOD(clock_settime,	mv_rtc_settime),
83
84	{ 0, 0 },
85};
86
87static driver_t mv_rtc_driver = {
88	"rtc",
89	mv_rtc_methods,
90	sizeof(struct mv_rtc_softc),
91};
92static devclass_t mv_rtc_devclass;
93
94DRIVER_MODULE(mv_rtc, simplebus, mv_rtc_driver, mv_rtc_devclass, 0, 0);
95
96static int
97mv_rtc_probe(device_t dev)
98{
99
100	if (!ofw_bus_status_okay(dev))
101		return (ENXIO);
102
103	if (!ofw_bus_is_compatible(dev, "mrvl,rtc"))
104		return (ENXIO);
105
106	device_set_desc(dev, "Marvell Integrated RTC");
107	return (BUS_PROBE_DEFAULT);
108}
109
110static int
111mv_rtc_attach(device_t dev)
112{
113	struct mv_rtc_softc *sc;
114
115	sc = device_get_softc(dev);
116	sc->dev = dev;
117
118	clock_register(dev, 1000000);
119
120	if (bus_alloc_resources(dev, res_spec, sc->res)) {
121		device_printf(dev, "could not allocate resources\n");
122		return (ENXIO);
123	}
124
125	return (0);
126}
127
128static int
129mv_rtc_gettime(device_t dev, struct timespec *ts)
130{
131	struct clocktime ct;
132	struct mv_rtc_softc *sc;
133	uint32_t val;
134
135	sc = device_get_softc(dev);
136
137	val = mv_rtc_reg_read(sc, MV_RTC_TIME_REG);
138
139	ct.nsec = 0;
140	ct.sec = FROMBCD(val & 0x7f);
141	ct.min = FROMBCD((val & 0x7f00) >> 8);
142	ct.hour = FROMBCD((val & 0x3f0000) >> 16);
143	ct.dow = FROMBCD((val & 0x7000000) >> 24) - 1;
144
145	val = mv_rtc_reg_read(sc, MV_RTC_DATE_REG);
146
147	ct.day = FROMBCD(val & 0x7f);
148	ct.mon = FROMBCD((val & 0x1f00) >> 8);
149	ct.year = YEAR_BASE + FROMBCD((val & 0xff0000) >> 16);
150
151	return (clock_ct_to_ts(&ct, ts));
152}
153
154static int
155mv_rtc_settime(device_t dev, struct timespec *ts)
156{
157	struct clocktime ct;
158	struct mv_rtc_softc *sc;
159	uint32_t val;
160
161	sc = device_get_softc(dev);
162
163	/* Resolution: 1 sec */
164	if (ts->tv_nsec >= 500000000)
165		ts->tv_sec++;
166	ts->tv_nsec = 0;
167	clock_ts_to_ct(ts, &ct);
168
169	val = TOBCD(ct.sec) | (TOBCD(ct.min) << 8) |
170	    (TOBCD(ct.hour) << 16) | (TOBCD( ct.dow + 1) << 24);
171	mv_rtc_reg_write(sc, MV_RTC_TIME_REG, val);
172
173	val = TOBCD(ct.day) | (TOBCD(ct.mon) << 8) |
174	    (TOBCD(ct.year - YEAR_BASE) << 16);
175	mv_rtc_reg_write(sc, MV_RTC_DATE_REG, val);
176
177	return (0);
178}
179
180static uint32_t
181mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off)
182{
183
184	return (bus_read_4(sc->res[0], off));
185}
186
187static int
188mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off, uint32_t val)
189{
190
191	bus_write_4(sc->res[0], off, val);
192	return (0);
193}
194