xref: /freebsd/sys/arm/nvidia/tegra_rtc.c (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1 /*-
2  * Copyright (c) 2016 Michal Meloun <mmel@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 /*
31  * RTC driver for Tegra SoCs.
32  */
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/clock.h>
37 #include <sys/kernel.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/module.h>
42 #include <sys/resource.h>
43 
44 #include <machine/bus.h>
45 #include <machine/resource.h>
46 #include <sys/rman.h>
47 
48 #include <dev/extres/clk/clk.h>
49 #include <dev/ofw/ofw_bus.h>
50 #include <dev/ofw/ofw_bus_subr.h>
51 
52 #include "clock_if.h"
53 
54 #define	RTC_CONTROL				0x00
55 #define	RTC_BUSY				0x04
56 #define	 RTC_BUSY_STATUS				(1 << 0)
57 #define	RTC_SECONDS				0x08
58 #define	RTC_SHADOW_SECONDS			0x0c
59 #define	RTC_MILLI_SECONDS			0x10
60 #define	RTC_SECONDS_ALARM0			0x14
61 #define	RTC_SECONDS_ALARM1			0x18
62 #define	RTC_MILLI_SECONDS_ALARM			0x1c
63 #define	RTC_SECONDS_COUNTDOWN_ALARM		0x20
64 #define	RTC_MILLI_SECONDS_COUNTDOW_ALARM	0x24
65 #define	RTC_INTR_MASK				0x28
66 #define	 RTC_INTR_MSEC_CDN_ALARM			(1 << 4)
67 #define	 RTC_INTR_SEC_CDN_ALARM				(1 << 3)
68 #define	 RTC_INTR_MSEC_ALARM				(1 << 2)
69 #define	 RTC_INTR_SEC_ALARM1				(1 << 1)
70 #define	 RTC_INTR_SEC_ALARM0				(1 << 0)
71 
72 #define	RTC_INTR_STATUS				0x2c
73 #define	RTC_INTR_SOURCE				0x30
74 #define	RTC_INTR_SET				0x34
75 #define	RTC_CORRECTION_FACTOR			0x38
76 
77 #define	WR4(_sc, _r, _v)	bus_write_4((_sc)->mem_res, (_r), (_v))
78 #define	RD4(_sc, _r)		bus_read_4((_sc)->mem_res, (_r))
79 
80 #define	LOCK(_sc)		mtx_lock(&(_sc)->mtx)
81 #define	UNLOCK(_sc)		mtx_unlock(&(_sc)->mtx)
82 #define	SLEEP(_sc, timeout)						\
83 	mtx_sleep(sc, &sc->mtx, 0, "rtcwait", timeout);
84 #define	LOCK_INIT(_sc)							\
85 	mtx_init(&_sc->mtx, device_get_nameunit(_sc->dev), "tegra_rtc", MTX_DEF)
86 #define	LOCK_DESTROY(_sc)	mtx_destroy(&_sc->mtx)
87 #define	ASSERT_LOCKED(_sc)	mtx_assert(&_sc->mtx, MA_OWNED)
88 #define	ASSERT_UNLOCKED(_sc)	mtx_assert(&_sc->mtx, MA_NOTOWNED)
89 
90 static struct ofw_compat_data compat_data[] = {
91 	{"nvidia,tegra124-rtc",	1},
92 	{NULL,			0}
93 };
94 
95 struct tegra_rtc_softc {
96 	device_t		dev;
97 	struct mtx		mtx;
98 
99 	struct resource		*mem_res;
100 	struct resource		*irq_res;
101 	void			*irq_h;
102 
103 	clk_t			clk;
104 	uint32_t		core_freq;
105 };
106 
107 static void
108 tegra_rtc_wait(struct tegra_rtc_softc *sc)
109 {
110 	int timeout;
111 
112 	for (timeout = 500; timeout >0; timeout--) {
113 		if ((RD4(sc, RTC_BUSY) & RTC_BUSY_STATUS) == 0)
114 			break;
115 		DELAY(1);
116 	}
117 	if (timeout <= 0)
118 		device_printf(sc->dev, "Device busy timeouted\n");
119 
120 }
121 
122 /*
123  * Get the time of day clock and return it in ts.
124  * Return 0 on success, an error number otherwise.
125  */
126 static int
127 tegra_rtc_gettime(device_t dev, struct timespec *ts)
128 {
129 	struct tegra_rtc_softc *sc;
130 	struct timeval tv;
131 	uint32_t msec, sec;
132 
133 	sc = device_get_softc(dev);
134 
135 	LOCK(sc);
136 	msec = RD4(sc, RTC_MILLI_SECONDS);
137 	sec = RD4(sc, RTC_SHADOW_SECONDS);
138 	UNLOCK(sc);
139 	tv.tv_sec = sec;
140 	tv.tv_usec = msec * 1000;
141 	TIMEVAL_TO_TIMESPEC(&tv, ts);
142 	return (0);
143 }
144 
145 static int
146 tegra_rtc_settime(device_t dev, struct timespec *ts)
147 {
148 	struct tegra_rtc_softc *sc;
149 	struct timeval tv;
150 
151 	sc = device_get_softc(dev);
152 
153 	LOCK(sc);
154 	TIMESPEC_TO_TIMEVAL(&tv, ts);
155 	tegra_rtc_wait(sc);
156 	WR4(sc, RTC_SECONDS, tv.tv_sec);
157 	UNLOCK(sc);
158 
159 	return (0);
160 }
161 
162 static void
163 tegra_rtc_intr(void *arg)
164 {
165 	struct tegra_rtc_softc *sc;
166 	uint32_t status;
167 
168 	sc = (struct tegra_rtc_softc *)arg;
169 	LOCK(sc);
170 	status = RD4(sc, RTC_INTR_STATUS);
171 	WR4(sc, RTC_INTR_STATUS, status);
172 	UNLOCK(sc);
173 }
174 
175 static int
176 tegra_rtc_probe(device_t dev)
177 {
178 	if (!ofw_bus_status_okay(dev))
179 		return (ENXIO);
180 
181 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
182 		return (ENXIO);
183 
184 	return (BUS_PROBE_DEFAULT);
185 }
186 
187 static int
188 tegra_rtc_attach(device_t dev)
189 {
190 	int rv, rid;
191 	struct tegra_rtc_softc *sc;
192 
193 	sc = device_get_softc(dev);
194 	sc->dev = dev;
195 
196 	LOCK_INIT(sc);
197 
198 	/* Get the memory resource for the register mapping. */
199 	rid = 0;
200 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
201 	    RF_ACTIVE);
202 	if (sc->mem_res == NULL) {
203 		device_printf(dev, "Cannot map registers.\n");
204 		rv = ENXIO;
205 		goto fail;
206 	}
207 
208 	/* Allocate our IRQ resource. */
209 	rid = 0;
210 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
211 	    RF_ACTIVE);
212 	if (sc->irq_res == NULL) {
213 		device_printf(dev, "Cannot allocate interrupt.\n");
214 		rv = ENXIO;
215 		goto fail;
216 	}
217 
218 	/* OFW resources. */
219 	rv = clk_get_by_ofw_index(dev, 0, 0, &sc->clk);
220 	if (rv != 0) {
221 		device_printf(dev, "Cannot get i2c clock: %d\n", rv);
222 		goto fail;
223 	}
224 	rv = clk_enable(sc->clk);
225 	if (rv != 0) {
226 		device_printf(dev, "Cannot enable clock: %d\n", rv);
227 		goto fail;
228 	}
229 
230 	/* Init hardware. */
231 	WR4(sc, RTC_SECONDS_ALARM0, 0);
232 	WR4(sc, RTC_SECONDS_ALARM1, 0);
233 	WR4(sc, RTC_INTR_STATUS, 0xFFFFFFFF);
234 	WR4(sc, RTC_INTR_MASK, 0);
235 
236 	/* Setup  interrupt */
237 	rv = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
238 	    NULL, tegra_rtc_intr, sc, &sc->irq_h);
239 	if (rv) {
240 		device_printf(dev, "Cannot setup interrupt.\n");
241 		goto fail;
242 	}
243 
244 	/*
245 	 * Register as a time of day clock with 1-second resolution.
246 	 *
247 	 * XXXX Not yet, we don't have support for multiple RTCs
248 	 */
249 	/* clock_register(dev, 1000000); */
250 
251 	return (bus_generic_attach(dev));
252 
253 fail:
254 	if (sc->clk != NULL)
255 		clk_release(sc->clk);
256 	if (sc->irq_h != NULL)
257 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
258 	if (sc->irq_res != NULL)
259 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
260 	if (sc->mem_res != NULL)
261 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
262 	LOCK_DESTROY(sc);
263 
264 	return (rv);
265 }
266 
267 static int
268 tegra_rtc_detach(device_t dev)
269 {
270 	struct tegra_rtc_softc *sc;
271 
272 	sc = device_get_softc(dev);
273 	if (sc->irq_h != NULL)
274 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
275 	if (sc->irq_res != NULL)
276 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
277 	if (sc->mem_res != NULL)
278 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
279 
280 	LOCK_DESTROY(sc);
281 	return (bus_generic_detach(dev));
282 }
283 
284 static device_method_t tegra_rtc_methods[] = {
285 	/* Device interface */
286 	DEVMETHOD(device_probe,		tegra_rtc_probe),
287 	DEVMETHOD(device_attach,	tegra_rtc_attach),
288 	DEVMETHOD(device_detach,	tegra_rtc_detach),
289 
290 	/* clock interface */
291 	DEVMETHOD(clock_gettime,	tegra_rtc_gettime),
292 	DEVMETHOD(clock_settime,	tegra_rtc_settime),
293 
294 	DEVMETHOD_END
295 };
296 
297 static devclass_t tegra_rtc_devclass;
298 static DEFINE_CLASS_0(rtc, tegra_rtc_driver, tegra_rtc_methods,
299     sizeof(struct tegra_rtc_softc));
300 DRIVER_MODULE(tegra_rtc, simplebus, tegra_rtc_driver, tegra_rtc_devclass,
301     NULL, NULL);
302