xref: /freebsd/sys/arm/mv/armada38x/armada38x_rtc.c (revision 6be3386466ab79a84b48429ae66244f21526d3df)
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 static devclass_t mv_rtc_devclass;
152 
153 DRIVER_MODULE(a38x_rtc, simplebus, mv_rtc_driver, mv_rtc_devclass, 0, 0);
154 
155 static void
156 mv_rtc_reset(device_t dev)
157 {
158 	struct mv_rtc_softc *sc;
159 
160 	sc = device_get_softc(dev);
161 
162 	/* Reset Test register */
163 	mv_rtc_reg_write(sc, RTC_TEST_CONFIG, 0);
164 	DELAY(500000);
165 
166 	/* Reset Time register */
167 	mv_rtc_reg_write(sc, RTC_TIME, 0);
168 	DELAY(62);
169 
170 	/* Reset Status register */
171 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
172 	DELAY(62);
173 
174 	/* Turn off Int1 and Int2 sources & clear the Alarm count */
175 	mv_rtc_reg_write(sc, RTC_IRQ_1_CONFIG, 0);
176 	mv_rtc_reg_write(sc, RTC_IRQ_2_CONFIG, 0);
177 	mv_rtc_reg_write(sc, RTC_ALARM_1, 0);
178 	mv_rtc_reg_write(sc, RTC_ALARM_2, 0);
179 
180 	/* Setup nominal register access timing */
181 	mv_rtc_reg_write(sc, RTC_CLOCK_CORR, RTC_NOMINAL_TIMING);
182 
183 	/* Reset Time register */
184 	mv_rtc_reg_write(sc, RTC_TIME, 0);
185 	DELAY(10);
186 
187 	/* Reset Status register */
188 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
189 	DELAY(50);
190 }
191 
192 static int
193 mv_rtc_probe(device_t dev)
194 {
195 
196 	if (!ofw_bus_status_okay(dev))
197 		return (ENXIO);
198 
199 	if (!ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data)
200 		return (ENXIO);
201 
202 	device_set_desc(dev, "Marvell Integrated RTC");
203 
204 	return (BUS_PROBE_DEFAULT);
205 }
206 
207 static int
208 mv_rtc_attach(device_t dev)
209 {
210 	struct mv_rtc_softc *sc;
211 	int unit, ret;
212 
213 	unit = device_get_unit(dev);
214 
215 	sc = device_get_softc(dev);
216 	sc->dev = dev;
217 	sc->rtc_type = ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data;
218 
219 	mtx_init(&sc->mutex, device_get_nameunit(dev), NULL, MTX_SPIN);
220 
221 	ret = bus_alloc_resources(dev, res_spec, sc->res);
222 	if (ret != 0) {
223 		device_printf(dev, "could not allocate resources\n");
224 		mtx_destroy(&sc->mutex);
225 		return (ENXIO);
226 	}
227 
228 	switch (sc->rtc_type) {
229 	case RTC_A38X:
230 		mv_rtc_configure_bus_a38x(sc);
231 		break;
232 	case RTC_A8K:
233 		mv_rtc_configure_bus_a8k(sc);
234 		break;
235 	default:
236 		panic("Unknown RTC type: %d", sc->rtc_type);
237 	}
238 	clock_register(dev, RTC_RES_US);
239 
240 	return (0);
241 }
242 
243 static int
244 mv_rtc_detach(device_t dev)
245 {
246 	struct mv_rtc_softc *sc;
247 
248 	sc = device_get_softc(dev);
249 
250 	mtx_destroy(&sc->mutex);
251 
252 	bus_release_resources(dev, res_spec, sc->res);
253 
254 	return (0);
255 }
256 
257 static int
258 mv_rtc_gettime(device_t dev, struct timespec *ts)
259 {
260 	struct mv_rtc_softc *sc;
261 	uint32_t val, val_check;
262 
263 	sc = device_get_softc(dev);
264 
265 	MV_RTC_LOCK(sc);
266 	/*
267 	 * According to HW Errata, if more than one second is detected
268 	 * between two time reads, then at least one of the reads gave
269 	 * an invalid value.
270 	 */
271 	do {
272 		val = mv_rtc_reg_read(sc, RTC_TIME);
273 		DELAY(100);
274 		val_check = mv_rtc_reg_read(sc, RTC_TIME);
275 	} while ((val_check - val) > 1);
276 
277 	MV_RTC_UNLOCK(sc);
278 
279 	ts->tv_sec = val_check;
280 	/* RTC resolution is 1 sec */
281 	ts->tv_nsec = 0;
282 
283 	return (0);
284 }
285 
286 static int
287 mv_rtc_settime(device_t dev, struct timespec *ts)
288 {
289 	struct mv_rtc_softc *sc;
290 
291 	sc = device_get_softc(dev);
292 
293 	/* RTC resolution is 1 sec */
294 	if (ts->tv_nsec >= HALF_OF_SEC_NS)
295 		ts->tv_sec++;
296 	ts->tv_nsec = 0;
297 
298 	MV_RTC_LOCK(sc);
299 
300 	if ((mv_rtc_reg_read(sc, RTC_CLOCK_CORR) & RTC_NOMINAL_TIMING_MASK) !=
301 	    RTC_NOMINAL_TIMING) {
302 		/* RTC was not resetted yet */
303 		mv_rtc_reset(dev);
304 	}
305 
306 	/*
307 	 * According to errata FE-3124064, Write to RTC TIME register
308 	 * may fail. As a workaround, before writing to RTC TIME register,
309 	 * issue a dummy write of 0x0 twice to RTC Status register.
310 	 */
311 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
312 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
313 	mv_rtc_reg_write(sc, RTC_TIME, ts->tv_sec);
314 	MV_RTC_UNLOCK(sc);
315 
316 	return (0);
317 }
318 
319 static inline uint32_t
320 mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off)
321 {
322 
323 	return (bus_read_4(sc->res[RTC_RES], off));
324 }
325 
326 /*
327  * According to the datasheet, the OS should wait 5us after every
328  * register write to the RTC hard macro so that the required update
329  * can occur without holding off the system bus
330  */
331 static inline int
332 mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off, uint32_t val)
333 {
334 
335 	bus_write_4(sc->res[RTC_RES], off, val);
336 	DELAY(5);
337 
338 	return (0);
339 }
340 
341 static inline void
342 mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc)
343 {
344 	int val;
345 
346 	val = bus_read_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL);
347 	val &= ~(A38X_RTC_WRCLK_PERIOD_MASK | A38X_RTC_READ_OUTPUT_DELAY_MASK);
348 	val |= A38X_RTC_WRCLK_PERIOD_MAX << A38X_RTC_WRCLK_PERIOD_SHIFT;
349 	val |= A38X_RTC_READ_OUTPUT_DELAY_MAX << A38X_RTC_READ_OUTPUT_DELAY_SHIFT;
350 	bus_write_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL, val);
351 }
352 
353 static inline void
354 mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc)
355 {
356 	int val;
357 
358 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
359 	val &= ~(A8K_RTC_WRCLK_PERIOD_MASK | A8K_RTC_WRCLK_SETUP_MASK);
360 	val |= A8K_RTC_WRCLK_PERIOD_VAL << A8K_RTC_WRCLK_PERIOD_SHIFT;
361 	val |= A8K_RTC_WRCLK_SETUP_VAL << A8K_RTC_WRCLK_SETUP_SHIFT;
362 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
363 
364 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
365 	val &= ~A8K_RTC_READ_OUTPUT_DELAY_MASK;
366 	val |= A8K_RTC_READ_OUTPUT_DELAY_VAL << A8K_RTC_READ_OUTPUT_DELAY_SHIFT;
367 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
368 }
369