xref: /freebsd/sys/arm/allwinner/aw_wdog.c (revision 18054d0220cfc8df9c9568c437bd6fbb59d53c3c)
1 /*-
2  * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  * Copyright (c) 2016 Emmanuel Vadot <manu@freebsd.org>
4  * Copyright (c) 2022 Julien Cassette <julien.cassette@gmail.com>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/eventhandler.h>
33 #include <sys/systm.h>
34 #include <sys/watchdog.h>
35 #include <sys/reboot.h>
36 #include <sys/bus.h>
37 #include <sys/kernel.h>
38 #include <sys/lock.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/rman.h>
42 
43 #include <dev/ofw/openfirm.h>
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46 
47 #include <machine/bus.h>
48 
49 #include <arm/allwinner/aw_wdog.h>
50 
51 #define	READ(_sc, _r) bus_read_4((_sc)->res, (_r))
52 #define	WRITE(_sc, _r, _v) bus_write_4((_sc)->res, (_r), (_v))
53 
54 #define	A10_WDOG_CTRL		0x00
55 #define	A31_WDOG_CTRL		0x10
56 #define	D1_WDOG_CTRL		0x10
57 #define	 WDOG_CTRL_RESTART	(1 << 0)
58 #define	 A31_WDOG_CTRL_KEY	(0xa57 << 1)
59 #define	 D1_WDOG_CTRL_KEY	(0xa57 << 1)
60 #define	A10_WDOG_MODE		0x04
61 #define	A31_WDOG_MODE		0x18
62 #define	D1_WDOG_MODE		0x18
63 #define	 D1_WDOG_MODE_KEY	(0x16AA << 16)
64 #define	 A10_WDOG_MODE_INTVL_SHIFT	3
65 #define	 A31_WDOG_MODE_INTVL_SHIFT	4
66 #define	 D1_WDOG_MODE_INTVL_SHIFT	4
67 #define	 A10_WDOG_MODE_RST_EN	(1 << 1)
68 #define	 WDOG_MODE_EN		(1 << 0)
69 #define	A31_WDOG_CONFIG		0x14
70 #define	D1_WDOG_CONFIG		0x14
71 #define	 A31_WDOG_CONFIG_RST_EN_SYSTEM	(1 << 0)
72 #define	 A31_WDOG_CONFIG_RST_EN_INT	(2 << 0)
73 #define	 D1_WDOG_CONFIG_KEY		(0x16AA << 16)
74 #define	 D1_WDOG_CONFIG_RST_EN_SYSTEM	(1 << 0)
75 #define	 D1_WDOG_CONFIG_RST_EN_INT	(2 << 0)
76 
77 struct aw_wdog_interval {
78 	uint64_t	milliseconds;
79 	unsigned int	value;
80 };
81 
82 struct aw_wdog_interval wd_intervals[] = {
83 	{   500,	 0 },
84 	{  1000,	 1 },
85 	{  2000,	 2 },
86 	{  3000,	 3 },
87 	{  4000,	 4 },
88 	{  5000,	 5 },
89 	{  6000,	 6 },
90 	{  8000,	 7 },
91 	{ 10000,	 8 },
92 	{ 12000,	 9 },
93 	{ 14000,	10 },
94 	{ 16000,	11 },
95 	{ 0,		 0 } /* sentinel */
96 };
97 
98 static struct aw_wdog_softc *aw_wdog_sc = NULL;
99 
100 struct aw_wdog_softc {
101 	device_t		dev;
102 	struct resource *	res;
103 	struct mtx		mtx;
104 	uint8_t			wdog_ctrl;
105 	uint32_t		wdog_ctrl_key;
106 	uint8_t			wdog_mode;
107 	uint32_t		wdog_mode_key;
108 	uint8_t			wdog_mode_intvl_shift;
109 	uint8_t			wdog_mode_en;
110 	uint8_t			wdog_config;
111 	uint32_t		wdog_config_value;
112 };
113 
114 #define	A10_WATCHDOG	1
115 #define	A31_WATCHDOG	2
116 #define	D1_WATCHDOG	3
117 
118 static struct ofw_compat_data compat_data[] = {
119 	{"allwinner,sun4i-a10-wdt", A10_WATCHDOG},
120 	{"allwinner,sun6i-a31-wdt", A31_WATCHDOG},
121 	{"allwinner,sun20i-d1-wdt", D1_WATCHDOG},
122 	{NULL,             0}
123 };
124 
125 static void aw_wdog_watchdog_fn(void *, u_int, int *);
126 static void aw_wdog_shutdown_fn(void *, int);
127 
128 static int
129 aw_wdog_probe(device_t dev)
130 {
131 
132 	if (!ofw_bus_status_okay(dev))
133 		return (ENXIO);
134 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
135 	case A10_WATCHDOG:
136 		device_set_desc(dev, "Allwinner A10 Watchdog");
137 		return (BUS_PROBE_DEFAULT);
138 	case A31_WATCHDOG:
139 		device_set_desc(dev, "Allwinner A31 Watchdog");
140 		return (BUS_PROBE_DEFAULT);
141 	case D1_WATCHDOG:
142 		device_set_desc(dev, "Allwinner D1 Watchdog");
143 		return (BUS_PROBE_DEFAULT);
144 	}
145 	return (ENXIO);
146 }
147 
148 static int
149 aw_wdog_attach(device_t dev)
150 {
151 	struct aw_wdog_softc *sc;
152 	int rid;
153 
154 	if (aw_wdog_sc != NULL)
155 		return (ENXIO);
156 
157 	sc = device_get_softc(dev);
158 	sc->dev = dev;
159 
160 	rid = 0;
161 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
162 	if (sc->res == NULL) {
163 		device_printf(dev, "could not allocate memory resource\n");
164 		return (ENXIO);
165 	}
166 
167 	aw_wdog_sc = sc;
168 
169 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
170 	case A10_WATCHDOG:
171 		sc->wdog_ctrl = A10_WDOG_CTRL;
172 		sc->wdog_mode = A10_WDOG_MODE;
173 		sc->wdog_mode_key = 0;
174 		sc->wdog_mode_intvl_shift = A10_WDOG_MODE_INTVL_SHIFT;
175 		sc->wdog_mode_en = A10_WDOG_MODE_RST_EN | WDOG_MODE_EN;
176 		break;
177 	case A31_WATCHDOG:
178 		sc->wdog_ctrl = A31_WDOG_CTRL;
179 		sc->wdog_ctrl_key = A31_WDOG_CTRL_KEY;
180 		sc->wdog_mode = A31_WDOG_MODE;
181 		sc->wdog_mode_key = 0;
182 		sc->wdog_mode_intvl_shift = A31_WDOG_MODE_INTVL_SHIFT;
183 		sc->wdog_mode_en = WDOG_MODE_EN;
184 		sc->wdog_config = A31_WDOG_CONFIG;
185 		sc->wdog_config_value = A31_WDOG_CONFIG_RST_EN_SYSTEM;
186 		break;
187 	case D1_WATCHDOG:
188 		sc->wdog_ctrl = D1_WDOG_CTRL;
189 		sc->wdog_ctrl_key = D1_WDOG_CTRL_KEY;
190 		sc->wdog_mode = D1_WDOG_MODE;
191 		sc->wdog_mode_key = D1_WDOG_MODE_KEY;
192 		sc->wdog_mode_intvl_shift = D1_WDOG_MODE_INTVL_SHIFT;
193 		sc->wdog_mode_en = WDOG_MODE_EN;
194 		sc->wdog_config = D1_WDOG_CONFIG;
195 		sc->wdog_config_value = D1_WDOG_CONFIG_KEY | D1_WDOG_CONFIG_RST_EN_SYSTEM;
196 		break;
197 	default:
198 		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->res);
199 		return (ENXIO);
200 	}
201 
202 	mtx_init(&sc->mtx, "AW Watchdog", "aw_wdog", MTX_DEF);
203 	EVENTHANDLER_REGISTER(watchdog_list, aw_wdog_watchdog_fn, sc, 0);
204 	EVENTHANDLER_REGISTER(shutdown_final, aw_wdog_shutdown_fn, sc,
205 	    SHUTDOWN_PRI_LAST - 1);
206 
207 	return (0);
208 }
209 
210 static void
211 aw_wdog_watchdog_fn(void *private, u_int cmd, int *error)
212 {
213 	struct aw_wdog_softc *sc;
214 	uint64_t ms;
215 	int i;
216 
217 	sc = private;
218 	mtx_lock(&sc->mtx);
219 
220 	cmd &= WD_INTERVAL;
221 
222 	if (cmd > 0) {
223 		ms = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000;
224 		i = 0;
225 		while (wd_intervals[i].milliseconds &&
226 		    (ms > wd_intervals[i].milliseconds))
227 			i++;
228 		if (wd_intervals[i].milliseconds) {
229 			WRITE(sc, sc->wdog_mode, sc->wdog_mode_key |
230 			  (wd_intervals[i].value << sc->wdog_mode_intvl_shift) |
231 			    sc->wdog_mode_en);
232 			WRITE(sc, sc->wdog_ctrl,
233 			    WDOG_CTRL_RESTART | sc->wdog_ctrl_key);
234 			if (sc->wdog_config)
235 				WRITE(sc, sc->wdog_config,
236 				    sc->wdog_config_value);
237 			*error = 0;
238 		}
239 		else {
240 			/*
241 			 * Can't arm
242 			 * disable watchdog as watchdog(9) requires
243 			 */
244 			device_printf(sc->dev,
245 			    "Can't arm, timeout is more than 16 sec\n");
246 			mtx_unlock(&sc->mtx);
247 			WRITE(sc, sc->wdog_mode, sc->wdog_mode_key);
248 			return;
249 		}
250 	}
251 	else
252 		WRITE(sc, sc->wdog_mode, sc->wdog_mode_key);
253 
254 	mtx_unlock(&sc->mtx);
255 }
256 
257 static void
258 aw_wdog_shutdown_fn(void *private, int howto)
259 {
260 	if ((howto & (RB_POWEROFF|RB_HALT)) == 0)
261 		aw_wdog_watchdog_reset();
262 }
263 
264 void
265 aw_wdog_watchdog_reset(void)
266 {
267 
268 	if (aw_wdog_sc == NULL) {
269 		printf("Reset: watchdog device has not been initialized\n");
270 		return;
271 	}
272 
273 	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_mode, aw_wdog_sc->wdog_mode_key |
274 	    (wd_intervals[0].value << aw_wdog_sc->wdog_mode_intvl_shift) |
275 	    aw_wdog_sc->wdog_mode_en);
276 	if (aw_wdog_sc->wdog_config)
277 		WRITE(aw_wdog_sc, aw_wdog_sc->wdog_config,
278 		      aw_wdog_sc->wdog_config_value);
279 	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_ctrl,
280 	    WDOG_CTRL_RESTART | aw_wdog_sc->wdog_ctrl_key);
281 	while(1)
282 		;
283 
284 }
285 
286 static device_method_t aw_wdog_methods[] = {
287 	DEVMETHOD(device_probe, aw_wdog_probe),
288 	DEVMETHOD(device_attach, aw_wdog_attach),
289 
290 	DEVMETHOD_END
291 };
292 
293 static driver_t aw_wdog_driver = {
294 	"aw_wdog",
295 	aw_wdog_methods,
296 	sizeof(struct aw_wdog_softc),
297 };
298 
299 DRIVER_MODULE(aw_wdog, simplebus, aw_wdog_driver, 0, 0);
300