aw_wdog.c revision 308325 
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: stable/11/sys/arm/allwinner/aw_wdog.c 308325 2016-11-05 04:30:44Z mmel $");
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/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	A10_WDOG_MODE		0x04
57#define	A31_WDOG_MODE		0x18
58#define	 A10_WDOG_MODE_INTVL_SHIFT	3
59#define	 A31_WDOG_MODE_INTVL_SHIFT	4
60#define	 A10_WDOG_MODE_RST_EN	(1 << 1)
61#define	 WDOG_MODE_EN		(1 << 0)
62#define	A31_WDOG_CONFIG		0x14
63#define	 A31_WDOG_CONFIG_RST_EN_SYSTEM	(1 << 0)
64#define	 A31_WDOG_CONFIG_RST_EN_INT	(2 << 0)
65
66struct aw_wdog_interval {
67	uint64_t	milliseconds;
68	unsigned int	value;
69};
70
71struct aw_wdog_interval wd_intervals[] = {
72	{   500,	 0 },
73	{  1000,	 1 },
74	{  2000,	 2 },
75	{  3000,	 3 },
76	{  4000,	 4 },
77	{  5000,	 5 },
78	{  6000,	 6 },
79	{  8000,	 7 },
80	{ 10000,	 8 },
81	{ 12000,	 9 },
82	{ 14000,	10 },
83	{ 16000,	11 },
84	{ 0,		 0 } /* sentinel */
85};
86
87static struct aw_wdog_softc *aw_wdog_sc = NULL;
88
89struct aw_wdog_softc {
90	device_t		dev;
91	struct resource *	res;
92	struct mtx		mtx;
93	uint8_t			wdog_ctrl;
94	uint8_t			wdog_mode;
95	uint8_t			wdog_mode_intvl_shift;
96	uint8_t			wdog_mode_en;
97	uint8_t			wdog_config;
98	uint8_t			wdog_config_value;
99};
100
101#define	A10_WATCHDOG	1
102#define	A31_WATCHDOG	2
103
104static struct ofw_compat_data compat_data[] = {
105	{"allwinner,sun4i-a10-wdt", A10_WATCHDOG},
106	{"allwinner,sun6i-a31-wdt", A31_WATCHDOG},
107	{NULL,             0}
108};
109
110static void aw_wdog_watchdog_fn(void *private, u_int cmd, int *error);
111
112static int
113aw_wdog_probe(device_t dev)
114{
115	struct aw_wdog_softc *sc;
116
117	sc = device_get_softc(dev);
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
132static int
133aw_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_mode = A31_WDOG_MODE;
163		sc->wdog_mode_intvl_shift = A31_WDOG_MODE_INTVL_SHIFT;
164		sc->wdog_mode_en = WDOG_MODE_EN;
165		sc->wdog_config = A31_WDOG_CONFIG;
166		sc->wdog_config_value = A31_WDOG_CONFIG_RST_EN_SYSTEM;
167		break;
168	default:
169		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->res);
170		return (ENXIO);
171	}
172
173	mtx_init(&sc->mtx, "AW Watchdog", "aw_wdog", MTX_DEF);
174	EVENTHANDLER_REGISTER(watchdog_list, aw_wdog_watchdog_fn, sc, 0);
175	return (0);
176}
177
178static void
179aw_wdog_watchdog_fn(void *private, u_int cmd, int *error)
180{
181	struct aw_wdog_softc *sc;
182	uint64_t ms;
183	int i;
184
185	sc = private;
186	mtx_lock(&sc->mtx);
187
188	cmd &= WD_INTERVAL;
189
190	if (cmd > 0) {
191		ms = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000;
192		i = 0;
193		while (wd_intervals[i].milliseconds &&
194		    (ms > wd_intervals[i].milliseconds))
195			i++;
196		if (wd_intervals[i].milliseconds) {
197			WRITE(sc, sc->wdog_mode,
198			  (wd_intervals[i].value << sc->wdog_mode_intvl_shift) |
199			    sc->wdog_mode_en);
200			WRITE(sc, sc->wdog_ctrl, WDOG_CTRL_RESTART);
201			if (sc->wdog_config)
202				WRITE(sc, sc->wdog_config,
203				    sc->wdog_config_value);
204			*error = 0;
205		}
206		else {
207			/*
208			 * Can't arm
209			 * disable watchdog as watchdog(9) requires
210			 */
211			device_printf(sc->dev,
212			    "Can't arm, timeout is more than 16 sec\n");
213			mtx_unlock(&sc->mtx);
214			WRITE(sc, sc->wdog_mode, 0);
215			return;
216		}
217	}
218	else
219		WRITE(sc, sc->wdog_mode, 0);
220
221	mtx_unlock(&sc->mtx);
222}
223
224void
225aw_wdog_watchdog_reset()
226{
227
228	if (aw_wdog_sc == NULL) {
229		printf("Reset: watchdog device has not been initialized\n");
230		return;
231	}
232
233	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_mode,
234	    (wd_intervals[0].value << aw_wdog_sc->wdog_mode_intvl_shift) |
235	    aw_wdog_sc->wdog_mode_en);
236	if (aw_wdog_sc->wdog_config)
237		WRITE(aw_wdog_sc, aw_wdog_sc->wdog_config,
238		      aw_wdog_sc->wdog_config_value);
239	while(1)
240		;
241
242}
243
244static device_method_t aw_wdog_methods[] = {
245	DEVMETHOD(device_probe, aw_wdog_probe),
246	DEVMETHOD(device_attach, aw_wdog_attach),
247
248	DEVMETHOD_END
249};
250
251static driver_t aw_wdog_driver = {
252	"aw_wdog",
253	aw_wdog_methods,
254	sizeof(struct aw_wdog_softc),
255};
256static devclass_t aw_wdog_devclass;
257
258DRIVER_MODULE(aw_wdog, simplebus, aw_wdog_driver, aw_wdog_devclass, 0, 0);
259