1/*-
2 * Copyright (c) 2011 Jakub Wojciech Klama <jceel@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 */
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/param.h>
31#include <sys/bus.h>
32#include <sys/time.h>
33#include <sys/clock.h>
34#include <sys/resource.h>
35#include <sys/systm.h>
36#include <sys/rman.h>
37#include <sys/kernel.h>
38#include <sys/module.h>
39
40#include <machine/bus.h>
41#include <machine/resource.h>
42
43#include <dev/ofw/ofw_bus.h>
44#include <dev/ofw/ofw_bus_subr.h>
45
46#include <arm/lpc/lpcreg.h>
47
48#include "clock_if.h"
49
50struct lpc_rtc_softc {
51	device_t			lr_dev;
52	struct resource	*		lr_mem_res;
53	bus_space_tag_t			lr_bst;
54	bus_space_handle_t		lr_bsh;
55};
56
57static int lpc_rtc_probe(device_t dev);
58static int lpc_rtc_attach(device_t dev);
59static int lpc_rtc_gettime(device_t dev, struct timespec *ts);
60static int lpc_rtc_settime(device_t, struct timespec *);
61
62static int
63lpc_rtc_probe(device_t dev)
64{
65
66	if (!ofw_bus_is_compatible(dev, "lpc,rtc"))
67		return (ENXIO);
68
69	device_set_desc(dev, "LPC32x0 real time clock");
70	return (BUS_PROBE_DEFAULT);
71}
72
73static int
74lpc_rtc_attach(device_t dev)
75{
76	struct lpc_rtc_softc *sc = device_get_softc(dev);
77	int rid = 0;
78
79	sc->lr_dev = dev;
80
81	clock_register(dev, 1000000);
82
83	sc->lr_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
84	    RF_ACTIVE);
85	if (!sc->lr_mem_res) {
86		device_printf(dev, "cannot allocate memory window\n");
87		return (ENXIO);
88	}
89
90	sc->lr_bst = rman_get_bustag(sc->lr_mem_res);
91	sc->lr_bsh = rman_get_bushandle(sc->lr_mem_res);
92
93	return (0);
94}
95
96static int
97lpc_rtc_gettime(device_t dev, struct timespec *ts)
98{
99	struct lpc_rtc_softc *sc = device_get_softc(dev);
100
101	ts->tv_sec = bus_space_read_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_UCOUNT);
102	ts->tv_nsec = 0;
103
104	return (0);
105}
106
107static int
108lpc_rtc_settime(device_t dev, struct timespec *ts)
109{
110	struct lpc_rtc_softc *sc = device_get_softc(dev);
111	uint32_t ctrl;
112
113	/* Stop RTC */
114	ctrl = bus_space_read_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_CTRL);
115	bus_space_write_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_CTRL, ctrl | LPC_RTC_CTRL_DISABLE);
116
117	/* Write actual value */
118	bus_space_write_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_UCOUNT, ts->tv_sec);
119
120	/* Start RTC */
121	ctrl = bus_space_read_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_CTRL);
122	bus_space_write_4(sc->lr_bst, sc->lr_bsh, LPC_RTC_CTRL, ctrl & ~LPC_RTC_CTRL_DISABLE);
123
124	return (0);
125}
126
127static device_method_t lpc_rtc_methods[] = {
128	/* Device interface */
129	DEVMETHOD(device_probe,		lpc_rtc_probe),
130	DEVMETHOD(device_attach,	lpc_rtc_attach),
131
132	/* Clock interface */
133	DEVMETHOD(clock_gettime,	lpc_rtc_gettime),
134	DEVMETHOD(clock_settime,	lpc_rtc_settime),
135
136	{ 0, 0 },
137};
138
139static driver_t lpc_rtc_driver = {
140	"rtc",
141	lpc_rtc_methods,
142	sizeof(struct lpc_rtc_softc),
143};
144
145static devclass_t lpc_rtc_devclass;
146
147DRIVER_MODULE(rtc, simplebus, lpc_rtc_driver, lpc_rtc_devclass, 0, 0);
148