xref: /freebsd/sys/arm/allwinner/aw_wdog.c (revision b6d40d93946decb19fc2cb278037a11ac9bd0701)
1 /*-
2  * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  * Copyright (c) 2016 Emmanuel Vadot <manu@freebsd.org>
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 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/watchdog.h>
33 #include <sys/reboot.h>
34 #include <sys/bus.h>
35 #include <sys/kernel.h>
36 #include <sys/lock.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/rman.h>
40 
41 #include <dev/ofw/openfirm.h>
42 #include <dev/ofw/ofw_bus.h>
43 #include <dev/ofw/ofw_bus_subr.h>
44 
45 #include <machine/bus.h>
46 #include <machine/machdep.h>
47 
48 #include <arm/allwinner/aw_wdog.h>
49 
50 #define	READ(_sc, _r) bus_read_4((_sc)->res, (_r))
51 #define	WRITE(_sc, _r, _v) bus_write_4((_sc)->res, (_r), (_v))
52 
53 #define	A10_WDOG_CTRL		0x00
54 #define	A31_WDOG_CTRL		0x10
55 #define	 WDOG_CTRL_RESTART	(1 << 0)
56 #define	 A31_WDOG_CTRL_KEY	(0xa57 << 1)
57 #define	A10_WDOG_MODE		0x04
58 #define	A31_WDOG_MODE		0x18
59 #define	 A10_WDOG_MODE_INTVL_SHIFT	3
60 #define	 A31_WDOG_MODE_INTVL_SHIFT	4
61 #define	 A10_WDOG_MODE_RST_EN	(1 << 1)
62 #define	 WDOG_MODE_EN		(1 << 0)
63 #define	A31_WDOG_CONFIG		0x14
64 #define	 A31_WDOG_CONFIG_RST_EN_SYSTEM	(1 << 0)
65 #define	 A31_WDOG_CONFIG_RST_EN_INT	(2 << 0)
66 
67 struct aw_wdog_interval {
68 	uint64_t	milliseconds;
69 	unsigned int	value;
70 };
71 
72 struct aw_wdog_interval wd_intervals[] = {
73 	{   500,	 0 },
74 	{  1000,	 1 },
75 	{  2000,	 2 },
76 	{  3000,	 3 },
77 	{  4000,	 4 },
78 	{  5000,	 5 },
79 	{  6000,	 6 },
80 	{  8000,	 7 },
81 	{ 10000,	 8 },
82 	{ 12000,	 9 },
83 	{ 14000,	10 },
84 	{ 16000,	11 },
85 	{ 0,		 0 } /* sentinel */
86 };
87 
88 static struct aw_wdog_softc *aw_wdog_sc = NULL;
89 
90 struct aw_wdog_softc {
91 	device_t		dev;
92 	struct resource *	res;
93 	struct mtx		mtx;
94 	uint8_t			wdog_ctrl;
95 	uint32_t		wdog_ctrl_key;
96 	uint8_t			wdog_mode;
97 	uint8_t			wdog_mode_intvl_shift;
98 	uint8_t			wdog_mode_en;
99 	uint8_t			wdog_config;
100 	uint8_t			wdog_config_value;
101 };
102 
103 #define	A10_WATCHDOG	1
104 #define	A31_WATCHDOG	2
105 
106 static struct ofw_compat_data compat_data[] = {
107 	{"allwinner,sun4i-a10-wdt", A10_WATCHDOG},
108 	{"allwinner,sun6i-a31-wdt", A31_WATCHDOG},
109 	{NULL,             0}
110 };
111 
112 static void aw_wdog_watchdog_fn(void *, u_int, int *);
113 static void aw_wdog_shutdown_fn(void *, int);
114 
115 static int
116 aw_wdog_probe(device_t dev)
117 {
118 
119 	if (!ofw_bus_status_okay(dev))
120 		return (ENXIO);
121 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
122 	case A10_WATCHDOG:
123 		device_set_desc(dev, "Allwinner A10 Watchdog");
124 		return (BUS_PROBE_DEFAULT);
125 	case A31_WATCHDOG:
126 		device_set_desc(dev, "Allwinner A31 Watchdog");
127 		return (BUS_PROBE_DEFAULT);
128 	}
129 	return (ENXIO);
130 }
131 
132 static int
133 aw_wdog_attach(device_t dev)
134 {
135 	struct aw_wdog_softc *sc;
136 	int rid;
137 
138 	if (aw_wdog_sc != NULL)
139 		return (ENXIO);
140 
141 	sc = device_get_softc(dev);
142 	sc->dev = dev;
143 
144 	rid = 0;
145 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
146 	if (sc->res == NULL) {
147 		device_printf(dev, "could not allocate memory resource\n");
148 		return (ENXIO);
149 	}
150 
151 	aw_wdog_sc = sc;
152 
153 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
154 	case A10_WATCHDOG:
155 		sc->wdog_ctrl = A10_WDOG_CTRL;
156 		sc->wdog_mode = A10_WDOG_MODE;
157 		sc->wdog_mode_intvl_shift = A10_WDOG_MODE_INTVL_SHIFT;
158 		sc->wdog_mode_en = A10_WDOG_MODE_RST_EN | WDOG_MODE_EN;
159 		break;
160 	case A31_WATCHDOG:
161 		sc->wdog_ctrl = A31_WDOG_CTRL;
162 		sc->wdog_ctrl_key = A31_WDOG_CTRL_KEY;
163 		sc->wdog_mode = A31_WDOG_MODE;
164 		sc->wdog_mode_intvl_shift = A31_WDOG_MODE_INTVL_SHIFT;
165 		sc->wdog_mode_en = WDOG_MODE_EN;
166 		sc->wdog_config = A31_WDOG_CONFIG;
167 		sc->wdog_config_value = A31_WDOG_CONFIG_RST_EN_SYSTEM;
168 		break;
169 	default:
170 		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->res);
171 		return (ENXIO);
172 	}
173 
174 	mtx_init(&sc->mtx, "AW Watchdog", "aw_wdog", MTX_DEF);
175 	EVENTHANDLER_REGISTER(watchdog_list, aw_wdog_watchdog_fn, sc, 0);
176 	EVENTHANDLER_REGISTER(shutdown_final, aw_wdog_shutdown_fn, sc,
177 	    SHUTDOWN_PRI_LAST - 1);
178 
179 	return (0);
180 }
181 
182 static void
183 aw_wdog_watchdog_fn(void *private, u_int cmd, int *error)
184 {
185 	struct aw_wdog_softc *sc;
186 	uint64_t ms;
187 	int i;
188 
189 	sc = private;
190 	mtx_lock(&sc->mtx);
191 
192 	cmd &= WD_INTERVAL;
193 
194 	if (cmd > 0) {
195 		ms = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000;
196 		i = 0;
197 		while (wd_intervals[i].milliseconds &&
198 		    (ms > wd_intervals[i].milliseconds))
199 			i++;
200 		if (wd_intervals[i].milliseconds) {
201 			WRITE(sc, sc->wdog_mode,
202 			  (wd_intervals[i].value << sc->wdog_mode_intvl_shift) |
203 			    sc->wdog_mode_en);
204 			WRITE(sc, sc->wdog_ctrl,
205 			    WDOG_CTRL_RESTART | sc->wdog_ctrl_key);
206 			if (sc->wdog_config)
207 				WRITE(sc, sc->wdog_config,
208 				    sc->wdog_config_value);
209 			*error = 0;
210 		}
211 		else {
212 			/*
213 			 * Can't arm
214 			 * disable watchdog as watchdog(9) requires
215 			 */
216 			device_printf(sc->dev,
217 			    "Can't arm, timeout is more than 16 sec\n");
218 			mtx_unlock(&sc->mtx);
219 			WRITE(sc, sc->wdog_mode, 0);
220 			return;
221 		}
222 	}
223 	else
224 		WRITE(sc, sc->wdog_mode, 0);
225 
226 	mtx_unlock(&sc->mtx);
227 }
228 
229 static void
230 aw_wdog_shutdown_fn(void *private, int howto)
231 {
232 	if ((howto & (RB_POWEROFF|RB_HALT)) == 0)
233 		aw_wdog_watchdog_reset();
234 }
235 
236 void
237 aw_wdog_watchdog_reset(void)
238 {
239 
240 	if (aw_wdog_sc == NULL) {
241 		printf("Reset: watchdog device has not been initialized\n");
242 		return;
243 	}
244 
245 	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_mode,
246 	    (wd_intervals[0].value << aw_wdog_sc->wdog_mode_intvl_shift) |
247 	    aw_wdog_sc->wdog_mode_en);
248 	if (aw_wdog_sc->wdog_config)
249 		WRITE(aw_wdog_sc, aw_wdog_sc->wdog_config,
250 		      aw_wdog_sc->wdog_config_value);
251 	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_ctrl,
252 	    WDOG_CTRL_RESTART | aw_wdog_sc->wdog_ctrl_key);
253 	while(1)
254 		;
255 
256 }
257 
258 static device_method_t aw_wdog_methods[] = {
259 	DEVMETHOD(device_probe, aw_wdog_probe),
260 	DEVMETHOD(device_attach, aw_wdog_attach),
261 
262 	DEVMETHOD_END
263 };
264 
265 static driver_t aw_wdog_driver = {
266 	"aw_wdog",
267 	aw_wdog_methods,
268 	sizeof(struct aw_wdog_softc),
269 };
270 static devclass_t aw_wdog_devclass;
271 
272 DRIVER_MODULE(aw_wdog, simplebus, aw_wdog_driver, aw_wdog_devclass, 0, 0);
273