xref: /freebsd/sys/arm/allwinner/aw_wdog.c (revision d9f0ce31900a48d1a2bfc1c8c86f79d1e831451a)
1 /*-
2  * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  * Copyright (c) 2016 Emmanuel Vadot <manu@bidouilliste.com>
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/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/lock.h>
36 #include <sys/module.h>
37 #include <sys/mutex.h>
38 #include <sys/rman.h>
39 
40 #include <dev/fdt/fdt_common.h>
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/cpufunc.h>
47 #include <machine/machdep.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	 WDOG_CTRL_RESTART	(1 << 0)
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 	uint8_t			wdog_mode;
96 	uint8_t			wdog_mode_intvl_shift;
97 	uint8_t			wdog_mode_en;
98 	uint8_t			wdog_config;
99 	uint8_t			wdog_config_value;
100 };
101 
102 #define	A10_WATCHDOG	1
103 #define	A31_WATCHDOG	2
104 
105 static struct ofw_compat_data compat_data[] = {
106 	{"allwinner,sun4i-a10-wdt", A10_WATCHDOG},
107 	{"allwinner,sun6i-a31-wdt", A31_WATCHDOG},
108 	{NULL,             0}
109 };
110 
111 static void aw_wdog_watchdog_fn(void *private, u_int cmd, int *error);
112 
113 static int
114 aw_wdog_probe(device_t dev)
115 {
116 	struct aw_wdog_softc *sc;
117 
118 	sc = device_get_softc(dev);
119 
120 	if (!ofw_bus_status_okay(dev))
121 		return (ENXIO);
122 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
123 	case A10_WATCHDOG:
124 		device_set_desc(dev, "Allwinner A10 Watchdog");
125 		return (BUS_PROBE_DEFAULT);
126 	case A31_WATCHDOG:
127 		device_set_desc(dev, "Allwinner A31 Watchdog");
128 		return (BUS_PROBE_DEFAULT);
129 	}
130 	return (ENXIO);
131 }
132 
133 static int
134 aw_wdog_attach(device_t dev)
135 {
136 	struct aw_wdog_softc *sc;
137 	int rid;
138 
139 	if (aw_wdog_sc != NULL)
140 		return (ENXIO);
141 
142 	sc = device_get_softc(dev);
143 	sc->dev = dev;
144 
145 	rid = 0;
146 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
147 	if (sc->res == NULL) {
148 		device_printf(dev, "could not allocate memory resource\n");
149 		return (ENXIO);
150 	}
151 
152 	aw_wdog_sc = sc;
153 
154 	switch (ofw_bus_search_compatible(dev, compat_data)->ocd_data) {
155 	case A10_WATCHDOG:
156 		sc->wdog_ctrl = A10_WDOG_CTRL;
157 		sc->wdog_mode = A10_WDOG_MODE;
158 		sc->wdog_mode_intvl_shift = A10_WDOG_MODE_INTVL_SHIFT;
159 		sc->wdog_mode_en = A10_WDOG_MODE_RST_EN | WDOG_MODE_EN;
160 		break;
161 	case A31_WATCHDOG:
162 		sc->wdog_ctrl = A31_WDOG_CTRL;
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 	return (0);
177 }
178 
179 static void
180 aw_wdog_watchdog_fn(void *private, u_int cmd, int *error)
181 {
182 	struct aw_wdog_softc *sc;
183 	uint64_t ms;
184 	int i;
185 
186 	sc = private;
187 	mtx_lock(&sc->mtx);
188 
189 	cmd &= WD_INTERVAL;
190 
191 	if (cmd > 0) {
192 		ms = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000;
193 		i = 0;
194 		while (wd_intervals[i].milliseconds &&
195 		    (ms > wd_intervals[i].milliseconds))
196 			i++;
197 		if (wd_intervals[i].milliseconds) {
198 			WRITE(sc, sc->wdog_mode,
199 			  (wd_intervals[i].value << sc->wdog_mode_intvl_shift) |
200 			    sc->wdog_mode_en);
201 			WRITE(sc, sc->wdog_ctrl, WDOG_CTRL_RESTART);
202 			if (sc->wdog_config)
203 				WRITE(sc, sc->wdog_config,
204 				    sc->wdog_config_value);
205 			*error = 0;
206 		}
207 		else {
208 			/*
209 			 * Can't arm
210 			 * disable watchdog as watchdog(9) requires
211 			 */
212 			device_printf(sc->dev,
213 			    "Can't arm, timeout is more than 16 sec\n");
214 			mtx_unlock(&sc->mtx);
215 			WRITE(sc, sc->wdog_mode, 0);
216 			return;
217 		}
218 	}
219 	else
220 		WRITE(sc, sc->wdog_mode, 0);
221 
222 	mtx_unlock(&sc->mtx);
223 }
224 
225 void
226 aw_wdog_watchdog_reset()
227 {
228 
229 	if (aw_wdog_sc == NULL) {
230 		printf("Reset: watchdog device has not been initialized\n");
231 		return;
232 	}
233 
234 	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_mode,
235 	    (wd_intervals[0].value << aw_wdog_sc->wdog_mode_intvl_shift) |
236 	    aw_wdog_sc->wdog_mode_en);
237 	if (aw_wdog_sc->wdog_config)
238 		WRITE(aw_wdog_sc, aw_wdog_sc->wdog_config,
239 		      aw_wdog_sc->wdog_config_value);
240 	while(1)
241 		;
242 
243 }
244 
245 static device_method_t aw_wdog_methods[] = {
246 	DEVMETHOD(device_probe, aw_wdog_probe),
247 	DEVMETHOD(device_attach, aw_wdog_attach),
248 
249 	DEVMETHOD_END
250 };
251 
252 static driver_t aw_wdog_driver = {
253 	"aw_wdog",
254 	aw_wdog_methods,
255 	sizeof(struct aw_wdog_softc),
256 };
257 static devclass_t aw_wdog_devclass;
258 
259 DRIVER_MODULE(aw_wdog, simplebus, aw_wdog_driver, aw_wdog_devclass, 0, 0);
260