1/*-
2 * Copyright (c) 2015 Luiz Otavio O Souza <loos@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/param.h>
28#include <sys/systm.h>
29#include <sys/bus.h>
30#include <sys/clock.h>
31#include <sys/kernel.h>
32#include <sys/lock.h>
33#include <sys/module.h>
34#include <sys/mutex.h>
35#include <sys/rman.h>
36
37#include <machine/bus.h>
38
39#include <dev/ofw/ofw_bus.h>
40#include <dev/ofw/ofw_bus_subr.h>
41#include <arm/ti/ti_sysc.h>
42#include <arm/ti/am335x/am335x_rtcvar.h>
43#include <arm/ti/am335x/am335x_rtcreg.h>
44
45#define	RTC_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
46#define	RTC_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
47#define	RTC_LOCK_INIT(_sc)	mtx_init(&(_sc)->sc_mtx, \
48    device_get_nameunit(_sc->sc_dev), "am335x_rtc", MTX_DEF)
49#define	RTC_LOCK_DESTROY(_sc)	mtx_destroy(&(_sc)->sc_mtx)
50
51#define	RTC_READ4(_sc, reg)		\
52	bus_read_4((_sc)->sc_mem_res, reg)
53#define	RTC_WRITE4(_sc, reg, value)	\
54	bus_write_4((_sc)->sc_mem_res, reg, value)
55
56#define	RTC_MAXIRQS		2
57
58struct am335x_rtc_softc {
59	device_t		sc_dev;
60	struct mtx		sc_mtx;
61	struct resource		*sc_irq_res[RTC_MAXIRQS];
62	struct resource		*sc_mem_res;
63};
64
65static struct am335x_rtc_softc *rtc_sc = NULL;
66static struct resource_spec am335x_rtc_irq_spec[] = {
67	{ SYS_RES_IRQ, 0,  RF_ACTIVE },
68	{ SYS_RES_IRQ, 1,  RF_ACTIVE },
69	{ -1, 0,  0 }
70};
71
72static int
73am335x_rtc_probe(device_t dev)
74{
75
76	if (!ofw_bus_status_okay(dev))
77		return (ENXIO);
78	if (!ofw_bus_is_compatible(dev, "ti,da830-rtc"))
79		return (ENXIO);
80	device_set_desc(dev, "AM335x RTC (power management mode)");
81
82	return (BUS_PROBE_DEFAULT);
83}
84
85static int
86am335x_rtc_attach(device_t dev)
87{
88	int rid;
89	struct am335x_rtc_softc *sc;
90	uint32_t rev;
91
92	if (rtc_sc != NULL)
93		return (ENXIO);
94	rtc_sc = sc = device_get_softc(dev);
95	sc->sc_dev = dev;
96	rid = 0;
97	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
98	    RF_ACTIVE);
99	if (!sc->sc_mem_res) {
100		device_printf(dev, "cannot allocate memory resources\n");
101		return (ENXIO);
102	}
103	if (bus_alloc_resources(dev, am335x_rtc_irq_spec, sc->sc_irq_res) != 0) {
104		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
105		device_printf(dev, "cannot allocate irq resources\n");
106		return (ENXIO);
107	}
108	RTC_LOCK_INIT(sc);
109
110	/* Enable the RTC module. */
111	ti_sysc_clock_enable(device_get_parent(dev));
112	rev = RTC_READ4(sc, RTC_REVISION);
113	device_printf(dev, "AM335X RTC v%d.%d.%d\n",
114            (rev >> 8) & 0x7, (rev >> 6) & 0x3, rev & 0x3f);
115	/* Unlock the RTC. */
116	RTC_WRITE4(sc, RTC_KICK0R, RTC_KICK0R_PASS);
117	RTC_WRITE4(sc, RTC_KICK1R, RTC_KICK1R_PASS);
118	/* Stop the RTC, we don't need it right now. */
119	RTC_WRITE4(sc, RTC_CTRL, 0);
120	/* Disable interrupts. */
121	RTC_WRITE4(sc, RTC_INTR, 0);
122	/* Ack any pending interrupt. */
123	RTC_WRITE4(sc, RTC_STATUS, RTC_STATUS_ALARM2 | RTC_STATUS_ALARM);
124	/* Enable external clock (xtal) and 32 kHz clock. */
125	RTC_WRITE4(sc, RTC_OSC, RTC_OSC_32KCLK_EN | RTC_OSC_32KCLK_SEL);
126	/* Enable pmic_pwr_enable. */
127	RTC_WRITE4(sc, RTC_PMIC, PMIC_PWR_ENABLE);
128
129	return (0);
130}
131
132static int
133am335x_rtc_detach(device_t dev)
134{
135	struct am335x_rtc_softc *sc;
136
137	sc = device_get_softc(dev);
138	if (sc->sc_irq_res[0] != NULL)
139		bus_release_resources(dev, am335x_rtc_irq_spec, sc->sc_irq_res);
140	if (sc->sc_mem_res)
141		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
142	RTC_LOCK_DESTROY(sc);
143
144	return (0);
145}
146
147void
148am335x_rtc_pmic_pwr_toggle(void)
149{
150	int timeout;
151	struct clocktime ct;
152	struct timespec ts;
153
154	/*
155	 * We stop the RTC so we don't need to check the STATUS.BUSY bit
156	 * before update ALARM2 registers.
157	 */
158	timeout = 10;
159	RTC_WRITE4(rtc_sc, RTC_CTRL, 0);
160	while (--timeout && RTC_READ4(rtc_sc, RTC_STATUS) & RTC_STATUS_RUN)
161		DELAY(100);
162	if (timeout == 0) {
163		device_printf(rtc_sc->sc_dev, "RTC does not stop.\n");
164		return;
165	}
166	/* Program the ALARM2 to fire in 2 seconds. */
167	ct.dow = 0;
168	ct.nsec = 0;
169	ct.sec = FROMBCD(RTC_READ4(rtc_sc, RTC_SECONDS) & 0x7f);
170	ct.min = FROMBCD(RTC_READ4(rtc_sc, RTC_MINUTES) & 0x7f);
171	ct.hour = FROMBCD(RTC_READ4(rtc_sc, RTC_HOURS) & 0x3f);
172	ct.day = FROMBCD(RTC_READ4(rtc_sc, RTC_DAYS) & 0x3f);
173	ct.mon = FROMBCD(RTC_READ4(rtc_sc, RTC_MONTHS) & 0x1f);
174	ct.year = FROMBCD(RTC_READ4(rtc_sc, RTC_YEARS) & 0xff);
175	ct.year += POSIX_BASE_YEAR;
176	clock_ct_to_ts(&ct, &ts);
177	ts.tv_sec += 2;
178	clock_ts_to_ct(&ts, &ct);
179	RTC_WRITE4(rtc_sc, RTC_ALARM2_SECONDS, TOBCD(ct.sec));
180	RTC_WRITE4(rtc_sc, RTC_ALARM2_MINUTES, TOBCD(ct.min));
181	RTC_WRITE4(rtc_sc, RTC_ALARM2_HOURS, TOBCD(ct.hour));
182	RTC_WRITE4(rtc_sc, RTC_ALARM2_DAYS, TOBCD(ct.day));
183	RTC_WRITE4(rtc_sc, RTC_ALARM2_MONTHS, TOBCD(ct.mon));
184	RTC_WRITE4(rtc_sc, RTC_ALARM2_YEARS, TOBCD(ct.year - POSIX_BASE_YEAR));
185	/* Enable ALARM2 interrupt. */
186	RTC_WRITE4(rtc_sc, RTC_INTR, RTC_INTR_ALARM2);
187	/* Start count. */
188	RTC_WRITE4(rtc_sc, RTC_CTRL, RTC_CTRL_RUN);
189}
190
191static device_method_t am335x_rtc_methods[] = {
192	DEVMETHOD(device_probe,		am335x_rtc_probe),
193	DEVMETHOD(device_attach,	am335x_rtc_attach),
194	DEVMETHOD(device_detach,	am335x_rtc_detach),
195
196	DEVMETHOD_END
197};
198
199static driver_t am335x_rtc_driver = {
200	"am335x_rtc",
201	am335x_rtc_methods,
202	sizeof(struct am335x_rtc_softc),
203};
204
205DRIVER_MODULE(am335x_rtc, simplebus, am335x_rtc_driver, 0, 0);
206MODULE_VERSION(am335x_rtc, 1);
207MODULE_DEPEND(am335x_rtc, simplebus, 1, 1, 1);
208MODULE_DEPEND(am335x_rtc, ti_sysc, 1, 1, 1);
209