xref: /freebsd/sys/arm/mv/armada38x/armada38x_rtc.c (revision 29fc4075e69fd27de0cded313ac6000165d99f8b)
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 #define	RTC_RES		0
96 #define	RTC_SOC_RES	1
97 
98 static struct resource_spec res_spec[] = {
99 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
100 	{ SYS_RES_MEMORY,	1,	RF_ACTIVE },
101 	{ -1, 0 }
102 };
103 
104 struct mv_rtc_softc {
105 	device_t	dev;
106 	struct resource	*res[2];
107 	struct mtx	mutex;
108 	int		rtc_type;
109 };
110 
111 static int mv_rtc_probe(device_t dev);
112 static int mv_rtc_attach(device_t dev);
113 static int mv_rtc_detach(device_t dev);
114 
115 static int mv_rtc_gettime(device_t dev, struct timespec *ts);
116 static int mv_rtc_settime(device_t dev, struct timespec *ts);
117 
118 static inline uint32_t mv_rtc_reg_read(struct mv_rtc_softc *sc,
119     bus_size_t off);
120 static inline int mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off,
121     uint32_t val);
122 static inline void mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc);
123 static inline void mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc);
124 
125 static device_method_t mv_rtc_methods[] = {
126 	DEVMETHOD(device_probe,		mv_rtc_probe),
127 	DEVMETHOD(device_attach,	mv_rtc_attach),
128 	DEVMETHOD(device_detach,	mv_rtc_detach),
129 
130 	DEVMETHOD(clock_gettime,	mv_rtc_gettime),
131 	DEVMETHOD(clock_settime,	mv_rtc_settime),
132 
133 	{ 0, 0 },
134 };
135 
136 static driver_t mv_rtc_driver = {
137 	"rtc",
138 	mv_rtc_methods,
139 	sizeof(struct mv_rtc_softc),
140 };
141 
142 #define  RTC_A38X	1
143 #define  RTC_A8K	2
144 
145 static struct ofw_compat_data mv_rtc_compat[] = {
146 	{"marvell,armada-380-rtc",	RTC_A38X},
147 	{"marvell,armada-8k-rtc",	RTC_A8K},
148 	{NULL,				0},
149 };
150 
151 DRIVER_MODULE(a38x_rtc, simplebus, mv_rtc_driver, 0, 0);
152 
153 static void
154 mv_rtc_reset(device_t dev)
155 {
156 	struct mv_rtc_softc *sc;
157 
158 	sc = device_get_softc(dev);
159 
160 	/* Reset Test register */
161 	mv_rtc_reg_write(sc, RTC_TEST_CONFIG, 0);
162 	DELAY(500000);
163 
164 	/* Reset Time register */
165 	mv_rtc_reg_write(sc, RTC_TIME, 0);
166 	DELAY(62);
167 
168 	/* Reset Status register */
169 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
170 	DELAY(62);
171 
172 	/* Turn off Int1 and Int2 sources & clear the Alarm count */
173 	mv_rtc_reg_write(sc, RTC_IRQ_1_CONFIG, 0);
174 	mv_rtc_reg_write(sc, RTC_IRQ_2_CONFIG, 0);
175 	mv_rtc_reg_write(sc, RTC_ALARM_1, 0);
176 	mv_rtc_reg_write(sc, RTC_ALARM_2, 0);
177 
178 	/* Setup nominal register access timing */
179 	mv_rtc_reg_write(sc, RTC_CLOCK_CORR, RTC_NOMINAL_TIMING);
180 
181 	/* Reset Time register */
182 	mv_rtc_reg_write(sc, RTC_TIME, 0);
183 	DELAY(10);
184 
185 	/* Reset Status register */
186 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
187 	DELAY(50);
188 }
189 
190 static int
191 mv_rtc_probe(device_t dev)
192 {
193 
194 	if (!ofw_bus_status_okay(dev))
195 		return (ENXIO);
196 
197 	if (!ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data)
198 		return (ENXIO);
199 
200 	device_set_desc(dev, "Marvell Integrated RTC");
201 
202 	return (BUS_PROBE_DEFAULT);
203 }
204 
205 static int
206 mv_rtc_attach(device_t dev)
207 {
208 	struct mv_rtc_softc *sc;
209 	int ret;
210 
211 	sc = device_get_softc(dev);
212 	sc->dev = dev;
213 	sc->rtc_type = ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data;
214 
215 	mtx_init(&sc->mutex, device_get_nameunit(dev), NULL, MTX_SPIN);
216 
217 	ret = bus_alloc_resources(dev, res_spec, sc->res);
218 	if (ret != 0) {
219 		device_printf(dev, "could not allocate resources\n");
220 		mtx_destroy(&sc->mutex);
221 		return (ENXIO);
222 	}
223 
224 	switch (sc->rtc_type) {
225 	case RTC_A38X:
226 		mv_rtc_configure_bus_a38x(sc);
227 		break;
228 	case RTC_A8K:
229 		mv_rtc_configure_bus_a8k(sc);
230 		break;
231 	default:
232 		panic("Unknown RTC type: %d", sc->rtc_type);
233 	}
234 	clock_register(dev, RTC_RES_US);
235 
236 	return (0);
237 }
238 
239 static int
240 mv_rtc_detach(device_t dev)
241 {
242 	struct mv_rtc_softc *sc;
243 
244 	sc = device_get_softc(dev);
245 
246 	mtx_destroy(&sc->mutex);
247 
248 	bus_release_resources(dev, res_spec, sc->res);
249 
250 	return (0);
251 }
252 
253 static int
254 mv_rtc_gettime(device_t dev, struct timespec *ts)
255 {
256 	struct mv_rtc_softc *sc;
257 	uint32_t val, val_check;
258 
259 	sc = device_get_softc(dev);
260 
261 	MV_RTC_LOCK(sc);
262 	/*
263 	 * According to HW Errata, if more than one second is detected
264 	 * between two time reads, then at least one of the reads gave
265 	 * an invalid value.
266 	 */
267 	do {
268 		val = mv_rtc_reg_read(sc, RTC_TIME);
269 		DELAY(100);
270 		val_check = mv_rtc_reg_read(sc, RTC_TIME);
271 	} while ((val_check - val) > 1);
272 
273 	MV_RTC_UNLOCK(sc);
274 
275 	ts->tv_sec = val_check;
276 	/* RTC resolution is 1 sec */
277 	ts->tv_nsec = 0;
278 
279 	return (0);
280 }
281 
282 static int
283 mv_rtc_settime(device_t dev, struct timespec *ts)
284 {
285 	struct mv_rtc_softc *sc;
286 
287 	sc = device_get_softc(dev);
288 
289 	/* RTC resolution is 1 sec */
290 	if (ts->tv_nsec >= HALF_OF_SEC_NS)
291 		ts->tv_sec++;
292 	ts->tv_nsec = 0;
293 
294 	MV_RTC_LOCK(sc);
295 
296 	if ((mv_rtc_reg_read(sc, RTC_CLOCK_CORR) & RTC_NOMINAL_TIMING_MASK) !=
297 	    RTC_NOMINAL_TIMING) {
298 		/* RTC was not resetted yet */
299 		mv_rtc_reset(dev);
300 	}
301 
302 	/*
303 	 * According to errata FE-3124064, Write to RTC TIME register
304 	 * may fail. As a workaround, before writing to RTC TIME register,
305 	 * issue a dummy write of 0x0 twice to RTC Status register.
306 	 */
307 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
308 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
309 	mv_rtc_reg_write(sc, RTC_TIME, ts->tv_sec);
310 	MV_RTC_UNLOCK(sc);
311 
312 	return (0);
313 }
314 
315 static inline uint32_t
316 mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off)
317 {
318 
319 	return (bus_read_4(sc->res[RTC_RES], off));
320 }
321 
322 /*
323  * According to the datasheet, the OS should wait 5us after every
324  * register write to the RTC hard macro so that the required update
325  * can occur without holding off the system bus
326  */
327 static inline int
328 mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off, uint32_t val)
329 {
330 
331 	bus_write_4(sc->res[RTC_RES], off, val);
332 	DELAY(5);
333 
334 	return (0);
335 }
336 
337 static inline void
338 mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc)
339 {
340 	int val;
341 
342 	val = bus_read_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL);
343 	val &= ~(A38X_RTC_WRCLK_PERIOD_MASK | A38X_RTC_READ_OUTPUT_DELAY_MASK);
344 	val |= A38X_RTC_WRCLK_PERIOD_MAX << A38X_RTC_WRCLK_PERIOD_SHIFT;
345 	val |= A38X_RTC_READ_OUTPUT_DELAY_MAX << A38X_RTC_READ_OUTPUT_DELAY_SHIFT;
346 	bus_write_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL, val);
347 }
348 
349 static inline void
350 mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc)
351 {
352 	int val;
353 
354 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
355 	val &= ~(A8K_RTC_WRCLK_PERIOD_MASK | A8K_RTC_WRCLK_SETUP_MASK);
356 	val |= A8K_RTC_WRCLK_PERIOD_VAL << A8K_RTC_WRCLK_PERIOD_SHIFT;
357 	val |= A8K_RTC_WRCLK_SETUP_VAL << A8K_RTC_WRCLK_SETUP_SHIFT;
358 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
359 
360 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
361 	val &= ~A8K_RTC_READ_OUTPUT_DELAY_MASK;
362 	val |= A8K_RTC_READ_OUTPUT_DELAY_VAL << A8K_RTC_READ_OUTPUT_DELAY_SHIFT;
363 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
364 }
365