xref: /freebsd/sys/arm/nvidia/tegra_rtc.c (revision e9ac41698b2f322d55ccf9da50a3596edb2c1800)
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 /*
29  * RTC driver for Tegra SoCs.
30  */
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/clock.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/module.h>
40 #include <sys/resource.h>
41 
42 #include <machine/bus.h>
43 #include <machine/resource.h>
44 #include <sys/rman.h>
45 
46 #include <dev/clk/clk.h>
47 #include <dev/ofw/ofw_bus.h>
48 #include <dev/ofw/ofw_bus_subr.h>
49 
50 #include "clock_if.h"
51 
52 #define	RTC_CONTROL				0x00
53 #define	RTC_BUSY				0x04
54 #define	 RTC_BUSY_STATUS				(1 << 0)
55 #define	RTC_SECONDS				0x08
56 #define	RTC_SHADOW_SECONDS			0x0c
57 #define	RTC_MILLI_SECONDS			0x10
58 #define	RTC_SECONDS_ALARM0			0x14
59 #define	RTC_SECONDS_ALARM1			0x18
60 #define	RTC_MILLI_SECONDS_ALARM			0x1c
61 #define	RTC_SECONDS_COUNTDOWN_ALARM		0x20
62 #define	RTC_MILLI_SECONDS_COUNTDOW_ALARM	0x24
63 #define	RTC_INTR_MASK				0x28
64 #define	 RTC_INTR_MSEC_CDN_ALARM			(1 << 4)
65 #define	 RTC_INTR_SEC_CDN_ALARM				(1 << 3)
66 #define	 RTC_INTR_MSEC_ALARM				(1 << 2)
67 #define	 RTC_INTR_SEC_ALARM1				(1 << 1)
68 #define	 RTC_INTR_SEC_ALARM0				(1 << 0)
69 
70 #define	RTC_INTR_STATUS				0x2c
71 #define	RTC_INTR_SOURCE				0x30
72 #define	RTC_INTR_SET				0x34
73 #define	RTC_CORRECTION_FACTOR			0x38
74 
75 #define	WR4(_sc, _r, _v)	bus_write_4((_sc)->mem_res, (_r), (_v))
76 #define	RD4(_sc, _r)		bus_read_4((_sc)->mem_res, (_r))
77 
78 #define	LOCK(_sc)		mtx_lock(&(_sc)->mtx)
79 #define	UNLOCK(_sc)		mtx_unlock(&(_sc)->mtx)
80 #define	SLEEP(_sc, timeout)						\
81 	mtx_sleep(sc, &sc->mtx, 0, "rtcwait", timeout);
82 #define	LOCK_INIT(_sc)							\
83 	mtx_init(&_sc->mtx, device_get_nameunit(_sc->dev), "tegra_rtc", MTX_DEF)
84 #define	LOCK_DESTROY(_sc)	mtx_destroy(&_sc->mtx)
85 #define	ASSERT_LOCKED(_sc)	mtx_assert(&_sc->mtx, MA_OWNED)
86 #define	ASSERT_UNLOCKED(_sc)	mtx_assert(&_sc->mtx, MA_NOTOWNED)
87 
88 static struct ofw_compat_data compat_data[] = {
89 	{"nvidia,tegra124-rtc",	1},
90 	{NULL,			0}
91 };
92 
93 struct tegra_rtc_softc {
94 	device_t		dev;
95 	struct mtx		mtx;
96 
97 	struct resource		*mem_res;
98 	struct resource		*irq_res;
99 	void			*irq_h;
100 
101 	clk_t			clk;
102 	uint32_t		core_freq;
103 };
104 
105 static void
106 tegra_rtc_wait(struct tegra_rtc_softc *sc)
107 {
108 	int timeout;
109 
110 	for (timeout = 500; timeout >0; timeout--) {
111 		if ((RD4(sc, RTC_BUSY) & RTC_BUSY_STATUS) == 0)
112 			break;
113 		DELAY(1);
114 	}
115 	if (timeout <= 0)
116 		device_printf(sc->dev, "Device busy timeouted\n");
117 
118 }
119 
120 /*
121  * Get the time of day clock and return it in ts.
122  * Return 0 on success, an error number otherwise.
123  */
124 static int
125 tegra_rtc_gettime(device_t dev, struct timespec *ts)
126 {
127 	struct tegra_rtc_softc *sc;
128 	struct timeval tv;
129 	uint32_t msec, sec;
130 
131 	sc = device_get_softc(dev);
132 
133 	LOCK(sc);
134 	msec = RD4(sc, RTC_MILLI_SECONDS);
135 	sec = RD4(sc, RTC_SHADOW_SECONDS);
136 	UNLOCK(sc);
137 	tv.tv_sec = sec;
138 	tv.tv_usec = msec * 1000;
139 	TIMEVAL_TO_TIMESPEC(&tv, ts);
140 	return (0);
141 }
142 
143 static int
144 tegra_rtc_settime(device_t dev, struct timespec *ts)
145 {
146 	struct tegra_rtc_softc *sc;
147 	struct timeval tv;
148 
149 	sc = device_get_softc(dev);
150 
151 	LOCK(sc);
152 	TIMESPEC_TO_TIMEVAL(&tv, ts);
153 	tegra_rtc_wait(sc);
154 	WR4(sc, RTC_SECONDS, tv.tv_sec);
155 	UNLOCK(sc);
156 
157 	return (0);
158 }
159 
160 static void
161 tegra_rtc_intr(void *arg)
162 {
163 	struct tegra_rtc_softc *sc;
164 	uint32_t status;
165 
166 	sc = (struct tegra_rtc_softc *)arg;
167 	LOCK(sc);
168 	status = RD4(sc, RTC_INTR_STATUS);
169 	WR4(sc, RTC_INTR_STATUS, status);
170 	UNLOCK(sc);
171 }
172 
173 static int
174 tegra_rtc_probe(device_t dev)
175 {
176 	if (!ofw_bus_status_okay(dev))
177 		return (ENXIO);
178 
179 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
180 		return (ENXIO);
181 
182 	return (BUS_PROBE_DEFAULT);
183 }
184 
185 static int
186 tegra_rtc_attach(device_t dev)
187 {
188 	int rv, rid;
189 	struct tegra_rtc_softc *sc;
190 
191 	sc = device_get_softc(dev);
192 	sc->dev = dev;
193 
194 	LOCK_INIT(sc);
195 
196 	/* Get the memory resource for the register mapping. */
197 	rid = 0;
198 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
199 	    RF_ACTIVE);
200 	if (sc->mem_res == NULL) {
201 		device_printf(dev, "Cannot map registers.\n");
202 		rv = ENXIO;
203 		goto fail;
204 	}
205 
206 	/* Allocate our IRQ resource. */
207 	rid = 0;
208 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
209 	    RF_ACTIVE);
210 	if (sc->irq_res == NULL) {
211 		device_printf(dev, "Cannot allocate interrupt.\n");
212 		rv = ENXIO;
213 		goto fail;
214 	}
215 
216 	/* OFW resources. */
217 	rv = clk_get_by_ofw_index(dev, 0, 0, &sc->clk);
218 	if (rv != 0) {
219 		device_printf(dev, "Cannot get i2c clock: %d\n", rv);
220 		goto fail;
221 	}
222 	rv = clk_enable(sc->clk);
223 	if (rv != 0) {
224 		device_printf(dev, "Cannot enable clock: %d\n", rv);
225 		goto fail;
226 	}
227 
228 	/* Init hardware. */
229 	WR4(sc, RTC_SECONDS_ALARM0, 0);
230 	WR4(sc, RTC_SECONDS_ALARM1, 0);
231 	WR4(sc, RTC_INTR_STATUS, 0xFFFFFFFF);
232 	WR4(sc, RTC_INTR_MASK, 0);
233 
234 	/* Setup  interrupt */
235 	rv = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
236 	    NULL, tegra_rtc_intr, sc, &sc->irq_h);
237 	if (rv) {
238 		device_printf(dev, "Cannot setup interrupt.\n");
239 		goto fail;
240 	}
241 
242 	/*
243 	 * Register as a time of day clock with 1-second resolution.
244 	 *
245 	 * XXXX Not yet, we don't have support for multiple RTCs
246 	 */
247 	/* clock_register(dev, 1000000); */
248 
249 	return (bus_generic_attach(dev));
250 
251 fail:
252 	if (sc->clk != NULL)
253 		clk_release(sc->clk);
254 	if (sc->irq_h != NULL)
255 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
256 	if (sc->irq_res != NULL)
257 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
258 	if (sc->mem_res != NULL)
259 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
260 	LOCK_DESTROY(sc);
261 
262 	return (rv);
263 }
264 
265 static int
266 tegra_rtc_detach(device_t dev)
267 {
268 	struct tegra_rtc_softc *sc;
269 
270 	sc = device_get_softc(dev);
271 	if (sc->irq_h != NULL)
272 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
273 	if (sc->irq_res != NULL)
274 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
275 	if (sc->mem_res != NULL)
276 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
277 
278 	LOCK_DESTROY(sc);
279 	return (bus_generic_detach(dev));
280 }
281 
282 static device_method_t tegra_rtc_methods[] = {
283 	/* Device interface */
284 	DEVMETHOD(device_probe,		tegra_rtc_probe),
285 	DEVMETHOD(device_attach,	tegra_rtc_attach),
286 	DEVMETHOD(device_detach,	tegra_rtc_detach),
287 
288 	/* clock interface */
289 	DEVMETHOD(clock_gettime,	tegra_rtc_gettime),
290 	DEVMETHOD(clock_settime,	tegra_rtc_settime),
291 
292 	DEVMETHOD_END
293 };
294 
295 static DEFINE_CLASS_0(rtc, tegra_rtc_driver, tegra_rtc_methods,
296     sizeof(struct tegra_rtc_softc));
297 DRIVER_MODULE(tegra_rtc, simplebus, tegra_rtc_driver, NULL, NULL);
298