xref: /freebsd/sys/arm/mv/armada38x/armada38x_rtc.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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/param.h>
29 #include <sys/bus.h>
30 #include <sys/lock.h>
31 #include <sys/time.h>
32 #include <sys/proc.h>
33 #include <sys/conf.h>
34 #include <sys/rman.h>
35 #include <sys/clock.h>
36 #include <sys/systm.h>
37 #include <sys/mutex.h>
38 #include <sys/types.h>
39 #include <sys/kernel.h>
40 #include <sys/module.h>
41 #include <sys/resource.h>
42 
43 #include <machine/bus.h>
44 #include <machine/resource.h>
45 
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/ofw_bus_subr.h>
48 
49 #include "clock_if.h"
50 
51 #define	RTC_RES_US		1000000
52 #define	HALF_OF_SEC_NS		500000000
53 
54 #define	RTC_STATUS		0x0
55 #define	RTC_TIME		0xC
56 #define	RTC_TEST_CONFIG		0x1C
57 #define	RTC_IRQ_1_CONFIG	0x4
58 #define	RTC_IRQ_2_CONFIG	0x8
59 #define	RTC_ALARM_1		0x10
60 #define	RTC_ALARM_2		0x14
61 #define	RTC_CLOCK_CORR		0x18
62 
63 #define	RTC_NOMINAL_TIMING	0x2000
64 #define	RTC_NOMINAL_TIMING_MASK	0x7fff
65 
66 #define	RTC_STATUS_ALARM1_MASK	0x1
67 #define	RTC_STATUS_ALARM2_MASK	0x2
68 
69 #define	MV_RTC_LOCK(sc)		mtx_lock_spin(&(sc)->mutex)
70 #define	MV_RTC_UNLOCK(sc)	mtx_unlock_spin(&(sc)->mutex)
71 
72 #define	A38X_RTC_BRIDGE_TIMING_CTRL		0x0
73 #define	A38X_RTC_WRCLK_PERIOD_SHIFT		0
74 #define	A38X_RTC_WRCLK_PERIOD_MASK		0x00000003FF
75 #define	A38X_RTC_WRCLK_PERIOD_MAX		0x3FF
76 #define	A38X_RTC_READ_OUTPUT_DELAY_SHIFT	26
77 #define	A38X_RTC_READ_OUTPUT_DELAY_MASK		0x007C000000
78 #define	A38X_RTC_READ_OUTPUT_DELAY_MAX		0x1F
79 
80 #define	A8K_RTC_BRIDGE_TIMING_CTRL0		0x0
81 #define	A8K_RTC_WRCLK_PERIOD_SHIFT		0
82 #define	A8K_RTC_WRCLK_PERIOD_MASK		0x000000FFFF
83 #define	A8K_RTC_WRCLK_PERIOD_VAL		0x3FF
84 #define	A8K_RTC_WRCLK_SETUP_SHIFT		16
85 #define	A8K_RTC_WRCLK_SETUP_MASK		0x00FFFF0000
86 #define	A8K_RTC_WRCLK_SETUP_VAL			29
87 #define	A8K_RTC_BRIDGE_TIMING_CTRL1		0x4
88 #define	A8K_RTC_READ_OUTPUT_DELAY_SHIFT		0
89 #define	A8K_RTC_READ_OUTPUT_DELAY_MASK		0x000000FFFF
90 #define	A8K_RTC_READ_OUTPUT_DELAY_VAL		0x3F
91 
92 #define	RTC_RES		0
93 #define	RTC_SOC_RES	1
94 
95 static struct resource_spec res_spec[] = {
96 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
97 	{ SYS_RES_MEMORY,	1,	RF_ACTIVE },
98 	{ -1, 0 }
99 };
100 
101 struct mv_rtc_softc {
102 	device_t	dev;
103 	struct resource	*res[2];
104 	struct mtx	mutex;
105 	int		rtc_type;
106 };
107 
108 static int mv_rtc_probe(device_t dev);
109 static int mv_rtc_attach(device_t dev);
110 static int mv_rtc_detach(device_t dev);
111 
112 static int mv_rtc_gettime(device_t dev, struct timespec *ts);
113 static int mv_rtc_settime(device_t dev, struct timespec *ts);
114 
115 static inline uint32_t mv_rtc_reg_read(struct mv_rtc_softc *sc,
116     bus_size_t off);
117 static inline int mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off,
118     uint32_t val);
119 static inline void mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc);
120 static inline void mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc);
121 
122 static device_method_t mv_rtc_methods[] = {
123 	DEVMETHOD(device_probe,		mv_rtc_probe),
124 	DEVMETHOD(device_attach,	mv_rtc_attach),
125 	DEVMETHOD(device_detach,	mv_rtc_detach),
126 
127 	DEVMETHOD(clock_gettime,	mv_rtc_gettime),
128 	DEVMETHOD(clock_settime,	mv_rtc_settime),
129 
130 	{ 0, 0 },
131 };
132 
133 static driver_t mv_rtc_driver = {
134 	"rtc",
135 	mv_rtc_methods,
136 	sizeof(struct mv_rtc_softc),
137 };
138 
139 #define  RTC_A38X	1
140 #define  RTC_A8K	2
141 
142 static struct ofw_compat_data mv_rtc_compat[] = {
143 	{"marvell,armada-380-rtc",	RTC_A38X},
144 	{"marvell,armada-8k-rtc",	RTC_A8K},
145 	{NULL,				0},
146 };
147 
148 DRIVER_MODULE(a38x_rtc, simplebus, mv_rtc_driver, 0, 0);
149 
150 static void
151 mv_rtc_reset(device_t dev)
152 {
153 	struct mv_rtc_softc *sc;
154 
155 	sc = device_get_softc(dev);
156 
157 	/* Reset Test register */
158 	mv_rtc_reg_write(sc, RTC_TEST_CONFIG, 0);
159 	DELAY(500000);
160 
161 	/* Reset Time register */
162 	mv_rtc_reg_write(sc, RTC_TIME, 0);
163 	DELAY(62);
164 
165 	/* Reset Status register */
166 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
167 	DELAY(62);
168 
169 	/* Turn off Int1 and Int2 sources & clear the Alarm count */
170 	mv_rtc_reg_write(sc, RTC_IRQ_1_CONFIG, 0);
171 	mv_rtc_reg_write(sc, RTC_IRQ_2_CONFIG, 0);
172 	mv_rtc_reg_write(sc, RTC_ALARM_1, 0);
173 	mv_rtc_reg_write(sc, RTC_ALARM_2, 0);
174 
175 	/* Setup nominal register access timing */
176 	mv_rtc_reg_write(sc, RTC_CLOCK_CORR, RTC_NOMINAL_TIMING);
177 
178 	/* Reset Time register */
179 	mv_rtc_reg_write(sc, RTC_TIME, 0);
180 	DELAY(10);
181 
182 	/* Reset Status register */
183 	mv_rtc_reg_write(sc, RTC_STATUS, (RTC_STATUS_ALARM1_MASK | RTC_STATUS_ALARM2_MASK));
184 	DELAY(50);
185 }
186 
187 static int
188 mv_rtc_probe(device_t dev)
189 {
190 
191 	if (!ofw_bus_status_okay(dev))
192 		return (ENXIO);
193 
194 	if (!ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data)
195 		return (ENXIO);
196 
197 	device_set_desc(dev, "Marvell Integrated RTC");
198 
199 	return (BUS_PROBE_DEFAULT);
200 }
201 
202 static int
203 mv_rtc_attach(device_t dev)
204 {
205 	struct mv_rtc_softc *sc;
206 	int ret;
207 
208 	sc = device_get_softc(dev);
209 	sc->dev = dev;
210 	sc->rtc_type = ofw_bus_search_compatible(dev, mv_rtc_compat)->ocd_data;
211 
212 	mtx_init(&sc->mutex, device_get_nameunit(dev), NULL, MTX_SPIN);
213 
214 	ret = bus_alloc_resources(dev, res_spec, sc->res);
215 	if (ret != 0) {
216 		device_printf(dev, "could not allocate resources\n");
217 		mtx_destroy(&sc->mutex);
218 		return (ENXIO);
219 	}
220 
221 	switch (sc->rtc_type) {
222 	case RTC_A38X:
223 		mv_rtc_configure_bus_a38x(sc);
224 		break;
225 	case RTC_A8K:
226 		mv_rtc_configure_bus_a8k(sc);
227 		break;
228 	default:
229 		panic("Unknown RTC type: %d", sc->rtc_type);
230 	}
231 	clock_register(dev, RTC_RES_US);
232 
233 	return (0);
234 }
235 
236 static int
237 mv_rtc_detach(device_t dev)
238 {
239 	struct mv_rtc_softc *sc;
240 
241 	sc = device_get_softc(dev);
242 
243 	mtx_destroy(&sc->mutex);
244 
245 	bus_release_resources(dev, res_spec, sc->res);
246 
247 	return (0);
248 }
249 
250 static int
251 mv_rtc_gettime(device_t dev, struct timespec *ts)
252 {
253 	struct mv_rtc_softc *sc;
254 	uint32_t val, val_check;
255 
256 	sc = device_get_softc(dev);
257 
258 	MV_RTC_LOCK(sc);
259 	/*
260 	 * According to HW Errata, if more than one second is detected
261 	 * between two time reads, then at least one of the reads gave
262 	 * an invalid value.
263 	 */
264 	do {
265 		val = mv_rtc_reg_read(sc, RTC_TIME);
266 		DELAY(100);
267 		val_check = mv_rtc_reg_read(sc, RTC_TIME);
268 	} while ((val_check - val) > 1);
269 
270 	MV_RTC_UNLOCK(sc);
271 
272 	ts->tv_sec = val_check;
273 	/* RTC resolution is 1 sec */
274 	ts->tv_nsec = 0;
275 
276 	return (0);
277 }
278 
279 static int
280 mv_rtc_settime(device_t dev, struct timespec *ts)
281 {
282 	struct mv_rtc_softc *sc;
283 
284 	sc = device_get_softc(dev);
285 
286 	/* RTC resolution is 1 sec */
287 	if (ts->tv_nsec >= HALF_OF_SEC_NS)
288 		ts->tv_sec++;
289 	ts->tv_nsec = 0;
290 
291 	MV_RTC_LOCK(sc);
292 
293 	if ((mv_rtc_reg_read(sc, RTC_CLOCK_CORR) & RTC_NOMINAL_TIMING_MASK) !=
294 	    RTC_NOMINAL_TIMING) {
295 		/* RTC was not resetted yet */
296 		mv_rtc_reset(dev);
297 	}
298 
299 	/*
300 	 * According to errata FE-3124064, Write to RTC TIME register
301 	 * may fail. As a workaround, before writing to RTC TIME register,
302 	 * issue a dummy write of 0x0 twice to RTC Status register.
303 	 */
304 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
305 	mv_rtc_reg_write(sc, RTC_STATUS, 0x0);
306 	mv_rtc_reg_write(sc, RTC_TIME, ts->tv_sec);
307 	MV_RTC_UNLOCK(sc);
308 
309 	return (0);
310 }
311 
312 static inline uint32_t
313 mv_rtc_reg_read(struct mv_rtc_softc *sc, bus_size_t off)
314 {
315 
316 	return (bus_read_4(sc->res[RTC_RES], off));
317 }
318 
319 /*
320  * According to the datasheet, the OS should wait 5us after every
321  * register write to the RTC hard macro so that the required update
322  * can occur without holding off the system bus
323  */
324 static inline int
325 mv_rtc_reg_write(struct mv_rtc_softc *sc, bus_size_t off, uint32_t val)
326 {
327 
328 	bus_write_4(sc->res[RTC_RES], off, val);
329 	DELAY(5);
330 
331 	return (0);
332 }
333 
334 static inline void
335 mv_rtc_configure_bus_a38x(struct mv_rtc_softc *sc)
336 {
337 	int val;
338 
339 	val = bus_read_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL);
340 	val &= ~(A38X_RTC_WRCLK_PERIOD_MASK | A38X_RTC_READ_OUTPUT_DELAY_MASK);
341 	val |= A38X_RTC_WRCLK_PERIOD_MAX << A38X_RTC_WRCLK_PERIOD_SHIFT;
342 	val |= A38X_RTC_READ_OUTPUT_DELAY_MAX << A38X_RTC_READ_OUTPUT_DELAY_SHIFT;
343 	bus_write_4(sc->res[RTC_SOC_RES], A38X_RTC_BRIDGE_TIMING_CTRL, val);
344 }
345 
346 static inline void
347 mv_rtc_configure_bus_a8k(struct mv_rtc_softc *sc)
348 {
349 	int val;
350 
351 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
352 	val &= ~(A8K_RTC_WRCLK_PERIOD_MASK | A8K_RTC_WRCLK_SETUP_MASK);
353 	val |= A8K_RTC_WRCLK_PERIOD_VAL << A8K_RTC_WRCLK_PERIOD_SHIFT;
354 	val |= A8K_RTC_WRCLK_SETUP_VAL << A8K_RTC_WRCLK_SETUP_SHIFT;
355 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
356 
357 	val = bus_read_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL0);
358 	val &= ~A8K_RTC_READ_OUTPUT_DELAY_MASK;
359 	val |= A8K_RTC_READ_OUTPUT_DELAY_VAL << A8K_RTC_READ_OUTPUT_DELAY_SHIFT;
360 	bus_write_4(sc->res[RTC_SOC_RES], A8K_RTC_BRIDGE_TIMING_CTRL1, val);
361 }
362