xref: /freebsd/sys/arm/nvidia/tegra_rtc.c (revision 243e928310d073338c5ec089f0dce238a80b9866)
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/fdt/fdt_common.h>
50 #include <dev/ofw/ofw_bus.h>
51 #include <dev/ofw/ofw_bus_subr.h>
52 
53 #include "clock_if.h"
54 
55 #define	RTC_CONTROL				0x00
56 #define	RTC_BUSY				0x04
57 #define	 RTC_BUSY_STATUS				(1 << 0)
58 #define	RTC_SECONDS				0x08
59 #define	RTC_SHADOW_SECONDS			0x0c
60 #define	RTC_MILLI_SECONDS			0x10
61 #define	RTC_SECONDS_ALARM0			0x14
62 #define	RTC_SECONDS_ALARM1			0x18
63 #define	RTC_MILLI_SECONDS_ALARM			0x1c
64 #define	RTC_SECONDS_COUNTDOWN_ALARM		0x20
65 #define	RTC_MILLI_SECONDS_COUNTDOW_ALARM	0x24
66 #define	RTC_INTR_MASK				0x28
67 #define	 RTC_INTR_MSEC_CDN_ALARM			(1 << 4)
68 #define	 RTC_INTR_SEC_CDN_ALARM				(1 << 3)
69 #define	 RTC_INTR_MSEC_ALARM				(1 << 2)
70 #define	 RTC_INTR_SEC_ALARM1				(1 << 1)
71 #define	 RTC_INTR_SEC_ALARM0				(1 << 0)
72 
73 #define	RTC_INTR_STATUS				0x2c
74 #define	RTC_INTR_SOURCE				0x30
75 #define	RTC_INTR_SET				0x34
76 #define	RTC_CORRECTION_FACTOR			0x38
77 
78 #define	WR4(_sc, _r, _v)	bus_write_4((_sc)->mem_res, (_r), (_v))
79 #define	RD4(_sc, _r)		bus_read_4((_sc)->mem_res, (_r))
80 
81 #define	LOCK(_sc)		mtx_lock(&(_sc)->mtx)
82 #define	UNLOCK(_sc)		mtx_unlock(&(_sc)->mtx)
83 #define	SLEEP(_sc, timeout)						\
84 	mtx_sleep(sc, &sc->mtx, 0, "rtcwait", timeout);
85 #define	LOCK_INIT(_sc)							\
86 	mtx_init(&_sc->mtx, device_get_nameunit(_sc->dev), "tegra_rtc", MTX_DEF)
87 #define	LOCK_DESTROY(_sc)	mtx_destroy(&_sc->mtx)
88 #define	ASSERT_LOCKED(_sc)	mtx_assert(&_sc->mtx, MA_OWNED)
89 #define	ASSERT_UNLOCKED(_sc)	mtx_assert(&_sc->mtx, MA_NOTOWNED)
90 
91 static struct ofw_compat_data compat_data[] = {
92 	{"nvidia,tegra124-rtc",	1},
93 	{NULL,			0}
94 };
95 
96 struct tegra_rtc_softc {
97 	device_t		dev;
98 	struct mtx		mtx;
99 
100 	struct resource		*mem_res;
101 	struct resource		*irq_res;
102 	void			*irq_h;
103 
104 	clk_t			clk;
105 	uint32_t		core_freq;
106 };
107 
108 static void
109 tegra_rtc_wait(struct tegra_rtc_softc *sc)
110 {
111 	int timeout;
112 
113 	for (timeout = 500; timeout >0; timeout--) {
114 		if ((RD4(sc, RTC_BUSY) & RTC_BUSY_STATUS) == 0)
115 			break;
116 		DELAY(1);
117 	}
118 	if (timeout <= 0)
119 		device_printf(sc->dev, "Device busy timeouted\n");
120 
121 }
122 
123 /*
124  * Get the time of day clock and return it in ts.
125  * Return 0 on success, an error number otherwise.
126  */
127 static int
128 tegra_rtc_gettime(device_t dev, struct timespec *ts)
129 {
130 	struct tegra_rtc_softc *sc;
131 	struct timeval tv;
132 	uint32_t msec, sec;
133 
134 	sc = device_get_softc(dev);
135 
136 	LOCK(sc);
137 	msec = RD4(sc, RTC_MILLI_SECONDS);
138 	sec = RD4(sc, RTC_SHADOW_SECONDS);
139 	UNLOCK(sc);
140 	tv.tv_sec = sec;
141 	tv.tv_usec = msec * 1000;
142 	TIMEVAL_TO_TIMESPEC(&tv, ts);
143 	return (0);
144 }
145 
146 
147 static int
148 tegra_rtc_settime(device_t dev, struct timespec *ts)
149 {
150 	struct tegra_rtc_softc *sc;
151 	struct timeval tv;
152 
153 	sc = device_get_softc(dev);
154 
155 	LOCK(sc);
156 	TIMESPEC_TO_TIMEVAL(&tv, ts);
157 	tegra_rtc_wait(sc);
158 	WR4(sc, RTC_SECONDS, tv.tv_sec);
159 	UNLOCK(sc);
160 
161 	return (0);
162 }
163 
164 
165 static void
166 tegra_rtc_intr(void *arg)
167 {
168 	struct tegra_rtc_softc *sc;
169 	uint32_t status;
170 
171 	sc = (struct tegra_rtc_softc *)arg;
172 	LOCK(sc);
173 	status = RD4(sc, RTC_INTR_STATUS);
174 	WR4(sc, RTC_INTR_STATUS, status);
175 	UNLOCK(sc);
176 }
177 
178 static int
179 tegra_rtc_probe(device_t dev)
180 {
181 	if (!ofw_bus_status_okay(dev))
182 		return (ENXIO);
183 
184 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
185 		return (ENXIO);
186 
187 	return (BUS_PROBE_DEFAULT);
188 }
189 
190 static int
191 tegra_rtc_attach(device_t dev)
192 {
193 	int rv, rid;
194 	struct tegra_rtc_softc *sc;
195 
196 	sc = device_get_softc(dev);
197 	sc->dev = dev;
198 
199 	LOCK_INIT(sc);
200 
201 	/* Get the memory resource for the register mapping. */
202 	rid = 0;
203 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
204 	    RF_ACTIVE);
205 	if (sc->mem_res == NULL) {
206 		device_printf(dev, "Cannot map registers.\n");
207 		rv = ENXIO;
208 		goto fail;
209 	}
210 
211 	/* Allocate our IRQ resource. */
212 	rid = 0;
213 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
214 	    RF_ACTIVE);
215 	if (sc->irq_res == NULL) {
216 		device_printf(dev, "Cannot allocate interrupt.\n");
217 		rv = ENXIO;
218 		goto fail;
219 	}
220 
221 	/* OFW resources. */
222 	rv = clk_get_by_ofw_index(dev, 0, &sc->clk);
223 	if (rv != 0) {
224 		device_printf(dev, "Cannot get i2c clock: %d\n", rv);
225 		goto fail;
226 	}
227 	rv = clk_enable(sc->clk);
228 	if (rv != 0) {
229 		device_printf(dev, "Cannot enable clock: %d\n", rv);
230 		goto fail;
231 	}
232 
233 	/* Init hardware. */
234 	WR4(sc, RTC_SECONDS_ALARM0, 0);
235 	WR4(sc, RTC_SECONDS_ALARM1, 0);
236 	WR4(sc, RTC_INTR_STATUS, 0xFFFFFFFF);
237 	WR4(sc, RTC_INTR_MASK, 0);
238 
239 	/* Setup  interrupt */
240 	rv = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
241 	    NULL, tegra_rtc_intr, sc, &sc->irq_h);
242 	if (rv) {
243 		device_printf(dev, "Cannot setup interrupt.\n");
244 		goto fail;
245 	}
246 
247 	/*
248 	 * Register as a time of day clock with 1-second resolution.
249 	 *
250 	 * XXXX Not yet, we don't have support for multiple RTCs
251 	 */
252 	/* clock_register(dev, 1000000); */
253 
254 	return (bus_generic_attach(dev));
255 
256 fail:
257 	if (sc->clk != NULL)
258 		clk_release(sc->clk);
259 	if (sc->irq_h != NULL)
260 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
261 	if (sc->irq_res != NULL)
262 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
263 	if (sc->mem_res != NULL)
264 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
265 	LOCK_DESTROY(sc);
266 
267 	return (rv);
268 }
269 
270 static int
271 tegra_rtc_detach(device_t dev)
272 {
273 	struct tegra_rtc_softc *sc;
274 
275 	sc = device_get_softc(dev);
276 	if (sc->irq_h != NULL)
277 		bus_teardown_intr(dev, sc->irq_res, sc->irq_h);
278 	if (sc->irq_res != NULL)
279 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
280 	if (sc->mem_res != NULL)
281 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
282 
283 	LOCK_DESTROY(sc);
284 	return (bus_generic_detach(dev));
285 }
286 
287 static device_method_t tegra_rtc_methods[] = {
288 	/* Device interface */
289 	DEVMETHOD(device_probe,		tegra_rtc_probe),
290 	DEVMETHOD(device_attach,	tegra_rtc_attach),
291 	DEVMETHOD(device_detach,	tegra_rtc_detach),
292 
293 	/* clock interface */
294 	DEVMETHOD(clock_gettime,	tegra_rtc_gettime),
295 	DEVMETHOD(clock_settime,	tegra_rtc_settime),
296 
297 	DEVMETHOD_END
298 };
299 
300 DEFINE_CLASS_0(tegra_rtc, tegra_rtc_driver, tegra_rtc_methods,
301     sizeof(struct tegra_rtc_softc));
302 static devclass_t tegra_rtc_devclass;
303 DRIVER_MODULE(tegra_rtc, simplebus, tegra_rtc_driver, tegra_rtc_devclass, 0, 0);
304