xref: /freebsd/sys/arm/mv/armada38x/armada38x_rtc.c (revision e17f5b1d)
1 /*-
2  * Copyright (c) 2015 Semihalf.
3  * Copyright (c) 2015 Stormshield.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/bus.h>
33 #include <sys/lock.h>
34 #include <sys/time.h>
35 #include <sys/proc.h>
36 #include <sys/conf.h>
37 #include <sys/rman.h>
38 #include <sys/clock.h>
39 #include <sys/systm.h>
40 #include <sys/mutex.h>
41 #include <sys/types.h>
42 #include <sys/kernel.h>
43 #include <sys/module.h>
44 #include <sys/resource.h>
45 
46 #include <machine/bus.h>
47 #include <machine/resource.h>
48 
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_RES_US		1000000
55 #define	HALF_OF_SEC_NS		500000000
56 
57 #define	RTC_STATUS		0x0
58 #define	RTC_TIME		0xC
59 #define	RTC_TEST_CONFIG		0x1C
60 #define	RTC_IRQ_1_CONFIG	0x4
61 #define	RTC_IRQ_2_CONFIG	0x8
62 #define	RTC_ALARM_1		0x10
63 #define	RTC_ALARM_2		0x14
64 #define	RTC_CLOCK_CORR		0x18
65 
66 #define	RTC_NOMINAL_TIMING	0x2000
67 #define	RTC_NOMINAL_TIMING_MASK	0x7fff
68 
69 #define	RTC_STATUS_ALARM1_MASK	0x1
70 #define	RTC_STATUS_ALARM2_MASK	0x2
71 
72 #define	MV_RTC_LOCK(sc)		mtx_lock_spin(&(sc)->mutex)
73 #define	MV_RTC_UNLOCK(sc)	mtx_unlock_spin(&(sc)->mutex)
74 
75 #define	A38X_RTC_BRIDGE_TIMING_CTRL		0x0
76 #define	A38X_RTC_WRCLK_PERIOD_SHIFT		0
77 #define	A38X_RTC_WRCLK_PERIOD_MASK		0x00000003FF
78 #define	A38X_RTC_WRCLK_PERIOD_MAX		0x3FF
79 #define	A38X_RTC_READ_OUTPUT_DELAY_SHIFT	26
80 #define	A38X_RTC_READ_OUTPUT_DELAY_MASK		0x007C000000
81 #define	A38X_RTC_READ_OUTPUT_DELAY_MAX		0x1F
82 
83 #define	A8K_RTC_BRIDGE_TIMING_CTRL0		0x0
84 #define	A8K_RTC_WRCLK_PERIOD_SHIFT		0
85 #define	A8K_RTC_WRCLK_PERIOD_MASK		0x000000FFFF
86 #define	A8K_RTC_WRCLK_PERIOD_VAL		0x3FF
87 #define	A8K_RTC_WRCLK_SETUP_SHIFT		16
88 #define	A8K_RTC_WRCLK_SETUP_MASK		0x00FFFF0000
89 #define	A8K_RTC_WRCLK_SETUP_VAL			29
90 #define	A8K_RTC_BRIDGE_TIMING_CTRL1		0x4
91 #define	A8K_RTC_READ_OUTPUT_DELAY_SHIFT		0
92 #define	A8K_RTC_READ_OUTPUT_DELAY_MASK		0x000000FFFF
93 #define	A8K_RTC_READ_OUTPUT_DELAY_VAL		0x3F
94 
95 
96 #define	RTC_RES		0
97 #define	RTC_SOC_RES	1
98 
99 
100 static struct resource_spec res_spec[] = {
101 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
102 	{ SYS_RES_MEMORY,	1,	RF_ACTIVE },
103 	{ -1, 0 }
104 };
105 
106 struct mv_rtc_softc {
107 	device_t	dev;
108 	struct resource	*res[2];
109 	struct mtx	mutex;
110 	int		rtc_type;
111 };
112 
113 static int mv_rtc_probe(device_t dev);
114 static int mv_rtc_attach(device_t dev);
115 static int mv_rtc_detach(device_t dev);
116 
117 static int mv_rtc_gettime(device_t dev, struct timespec *ts);
118 static int mv_rtc_settime(device_t dev, struct timespec *ts);
119 
120 static inline uint32_t mv_rtc_reg_read(struct mv_rtc_softc *sc,
121     bus_size_t off);
122 static inline int mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off,
123     uint32_t val);
124 static inline void mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc);
125 static inline void mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc);
126 
127 static device_method_t mv_rtc_methods[] = {
128 	DEVMETHOD(device_probe,		mv_rtc_probe),
129 	DEVMETHOD(device_attach,	mv_rtc_attach),
130 	DEVMETHOD(device_detach,	mv_rtc_detach),
131 
132 	DEVMETHOD(clock_gettime,	mv_rtc_gettime),
133 	DEVMETHOD(clock_settime,	mv_rtc_settime),
134 
135 	{ 0, 0 },
136 };
137 
138 static driver_t mv_rtc_driver = {
139 	"rtc",
140 	mv_rtc_methods,
141 	sizeof(struct mv_rtc_softc),
142 };
143 
144 #define  RTC_A38X	1
145 #define  RTC_A8K	2
146 
147 static struct ofw_compat_data mv_rtc_compat[] = {
148 	{"marvell,armada-380-rtc",	RTC_A38X},
149 	{"marvell,armada-8k-rtc",	RTC_A8K},
150 	{NULL,				0},
151 };
152 
153 static devclass_t mv_rtc_devclass;
154 
155 DRIVER_MODULE(a38x_rtc, simplebus, mv_rtc_driver, mv_rtc_devclass, 0, 0);
156 
157 static void
158 mv_rtc_reset(device_t dev)
159 {
160 	struct mv_rtc_softc *sc;
161 
162 	sc = device_get_softc(dev);
163 
164 	/* Reset Test register */
165 	mv_rtc_reg_write(sc, RTC_TEST_CONFIG, 0);
166 	DELAY(500000);
167 
168 	/* Reset Time register */
169 	mv_rtc_reg_write(sc, RTC_TIME, 0);
170 	DELAY(62);
171 
172 	/* Reset Status register */
173 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
174 	DELAY(62);
175 
176 	/* Turn off Int1 and Int2 sources & clear the Alarm count */
177 	mv_rtc_reg_write(sc, RTC_IRQ_1_CONFIG, 0);
178 	mv_rtc_reg_write(sc, RTC_IRQ_2_CONFIG, 0);
179 	mv_rtc_reg_write(sc, RTC_ALARM_1, 0);
180 	mv_rtc_reg_write(sc, RTC_ALARM_2, 0);
181 
182 	/* Setup nominal register access timing */
183 	mv_rtc_reg_write(sc, RTC_CLOCK_CORR, RTC_NOMINAL_TIMING);
184 
185 	/* Reset Time register */
186 	mv_rtc_reg_write(sc, RTC_TIME, 0);
187 	DELAY(10);
188 
189 	/* Reset Status register */
190 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
191 	DELAY(50);
192 }
193 
194 static int
195 mv_rtc_probe(device_t dev)
196 {
197 
198 	if (!ofw_bus_status_okay(dev))
199 		return (ENXIO);
200 
201 	if (!ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data)
202 		return (ENXIO);
203 
204 	device_set_desc(dev, "Marvell Integrated RTC");
205 
206 	return (BUS_PROBE_DEFAULT);
207 }
208 
209 static int
210 mv_rtc_attach(device_t dev)
211 {
212 	struct mv_rtc_softc *sc;
213 	int unit, ret;
214 
215 	unit = device_get_unit(dev);
216 
217 	sc = device_get_softc(dev);
218 	sc->dev = dev;
219 	sc->rtc_type = ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data;
220 
221 	mtx_init(&sc->mutex, device_get_nameunit(dev), NULL, MTX_SPIN);
222 
223 	ret = bus_alloc_resources(dev, res_spec, sc->res);
224 	if (ret != 0) {
225 		device_printf(dev, "could not allocate resources\n");
226 		mtx_destroy(&sc->mutex);
227 		return (ENXIO);
228 	}
229 
230 	switch (sc->rtc_type) {
231 	case RTC_A38X:
232 		mv_rtc_configure_bus_a38x(sc);
233 		break;
234 	case RTC_A8K:
235 		mv_rtc_configure_bus_a8k(sc);
236 		break;
237 	default:
238 		panic("Unknown RTC type: %d", sc->rtc_type);
239 	}
240 	clock_register(dev, RTC_RES_US);
241 
242 	return (0);
243 }
244 
245 static int
246 mv_rtc_detach(device_t dev)
247 {
248 	struct mv_rtc_softc *sc;
249 
250 	sc = device_get_softc(dev);
251 
252 	mtx_destroy(&sc->mutex);
253 
254 	bus_release_resources(dev, res_spec, sc->res);
255 
256 	return (0);
257 }
258 
259 static int
260 mv_rtc_gettime(device_t dev, struct timespec *ts)
261 {
262 	struct mv_rtc_softc *sc;
263 	uint32_t val, val_check;
264 
265 	sc = device_get_softc(dev);
266 
267 	MV_RTC_LOCK(sc);
268 	/*
269 	 * According to HW Errata, if more than one second is detected
270 	 * between two time reads, then at least one of the reads gave
271 	 * an invalid value.
272 	 */
273 	do {
274 		val = mv_rtc_reg_read(sc, RTC_TIME);
275 		DELAY(100);
276 		val_check = mv_rtc_reg_read(sc, RTC_TIME);
277 	} while ((val_check - val) > 1);
278 
279 	MV_RTC_UNLOCK(sc);
280 
281 	ts->tv_sec = val_check;
282 	/* RTC resolution is 1 sec */
283 	ts->tv_nsec = 0;
284 
285 	return (0);
286 }
287 
288 static int
289 mv_rtc_settime(device_t dev, struct timespec *ts)
290 {
291 	struct mv_rtc_softc *sc;
292 
293 	sc = device_get_softc(dev);
294 
295 	/* RTC resolution is 1 sec */
296 	if (ts->tv_nsec >= HALF_OF_SEC_NS)
297 		ts->tv_sec++;
298 	ts->tv_nsec = 0;
299 
300 	MV_RTC_LOCK(sc);
301 
302 	if ((mv_rtc_reg_read(sc, RTC_CLOCK_CORR) & RTC_NOMINAL_TIMING_MASK) !=
303 	    RTC_NOMINAL_TIMING) {
304 		/* RTC was not resetted yet */
305 		mv_rtc_reset(dev);
306 	}
307 
308 	/*
309 	 * According to errata FE-3124064, Write to RTC TIME register
310 	 * may fail. As a workaround, before writing to RTC TIME register,
311 	 * issue a dummy write of 0x0 twice to RTC Status register.
312 	 */
313 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
314 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
315 	mv_rtc_reg_write(sc, RTC_TIME, ts->tv_sec);
316 	MV_RTC_UNLOCK(sc);
317 
318 	return (0);
319 }
320 
321 static inline uint32_t
322 mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off)
323 {
324 
325 	return (bus_read_4(sc->res[RTC_RES], off));
326 }
327 
328 /*
329  * According to the datasheet, the OS should wait 5us after every
330  * register write to the RTC hard macro so that the required update
331  * can occur without holding off the system bus
332  */
333 static inline int
334 mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off, uint32_t val)
335 {
336 
337 	bus_write_4(sc->res[RTC_RES], off, val);
338 	DELAY(5);
339 
340 	return (0);
341 }
342 
343 static inline void
344 mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc)
345 {
346 	int val;
347 
348 	val = bus_read_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL);
349 	val &= ~(A38X_RTC_WRCLK_PERIOD_MASK | A38X_RTC_READ_OUTPUT_DELAY_MASK);
350 	val |= A38X_RTC_WRCLK_PERIOD_MAX << A38X_RTC_WRCLK_PERIOD_SHIFT;
351 	val |= A38X_RTC_READ_OUTPUT_DELAY_MAX << A38X_RTC_READ_OUTPUT_DELAY_SHIFT;
352 	bus_write_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL, val);
353 }
354 
355 static inline void
356 mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc)
357 {
358 	int val;
359 
360 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
361 	val &= ~(A8K_RTC_WRCLK_PERIOD_MASK | A8K_RTC_WRCLK_SETUP_MASK);
362 	val |= A8K_RTC_WRCLK_PERIOD_VAL << A8K_RTC_WRCLK_PERIOD_SHIFT;
363 	val |= A8K_RTC_WRCLK_SETUP_VAL << A8K_RTC_WRCLK_SETUP_SHIFT;
364 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
365 
366 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
367 	val &= ~A8K_RTC_READ_OUTPUT_DELAY_MASK;
368 	val |= A8K_RTC_READ_OUTPUT_DELAY_VAL << A8K_RTC_READ_OUTPUT_DELAY_SHIFT;
369 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
370 }
371