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/eventhandler.h>
32#include <sys/systm.h>
33#include <sys/watchdog.h>
34#include <sys/reboot.h>
35#include <sys/bus.h>
36#include <sys/kernel.h>
37#include <sys/lock.h>
38#include <sys/module.h>
39#include <sys/mutex.h>
40#include <sys/rman.h>
41
42#include <dev/ofw/openfirm.h>
43#include <dev/ofw/ofw_bus.h>
44#include <dev/ofw/ofw_bus_subr.h>
45
46#include <machine/bus.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	 A31_WDOG_CTRL_KEY	(0xa57 << 1)
58#define	A10_WDOG_MODE		0x04
59#define	A31_WDOG_MODE		0x18
60#define	 A10_WDOG_MODE_INTVL_SHIFT	3
61#define	 A31_WDOG_MODE_INTVL_SHIFT	4
62#define	 A10_WDOG_MODE_RST_EN	(1 << 1)
63#define	 WDOG_MODE_EN		(1 << 0)
64#define	A31_WDOG_CONFIG		0x14
65#define	 A31_WDOG_CONFIG_RST_EN_SYSTEM	(1 << 0)
66#define	 A31_WDOG_CONFIG_RST_EN_INT	(2 << 0)
67
68struct aw_wdog_interval {
69	uint64_t	milliseconds;
70	unsigned int	value;
71};
72
73struct aw_wdog_interval wd_intervals[] = {
74	{   500,	 0 },
75	{  1000,	 1 },
76	{  2000,	 2 },
77	{  3000,	 3 },
78	{  4000,	 4 },
79	{  5000,	 5 },
80	{  6000,	 6 },
81	{  8000,	 7 },
82	{ 10000,	 8 },
83	{ 12000,	 9 },
84	{ 14000,	10 },
85	{ 16000,	11 },
86	{ 0,		 0 } /* sentinel */
87};
88
89static struct aw_wdog_softc *aw_wdog_sc = NULL;
90
91struct aw_wdog_softc {
92	device_t		dev;
93	struct resource *	res;
94	struct mtx		mtx;
95	uint8_t			wdog_ctrl;
96	uint32_t		wdog_ctrl_key;
97	uint8_t			wdog_mode;
98	uint8_t			wdog_mode_intvl_shift;
99	uint8_t			wdog_mode_en;
100	uint8_t			wdog_config;
101	uint8_t			wdog_config_value;
102};
103
104#define	A10_WATCHDOG	1
105#define	A31_WATCHDOG	2
106
107static struct ofw_compat_data compat_data[] = {
108	{"allwinner,sun4i-a10-wdt", A10_WATCHDOG},
109	{"allwinner,sun6i-a31-wdt", A31_WATCHDOG},
110	{NULL,             0}
111};
112
113static void aw_wdog_watchdog_fn(void *, u_int, int *);
114static void aw_wdog_shutdown_fn(void *, int);
115
116static int
117aw_wdog_probe(device_t dev)
118{
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
133static int
134aw_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_ctrl_key = A31_WDOG_CTRL_KEY;
164		sc->wdog_mode = A31_WDOG_MODE;
165		sc->wdog_mode_intvl_shift = A31_WDOG_MODE_INTVL_SHIFT;
166		sc->wdog_mode_en = WDOG_MODE_EN;
167		sc->wdog_config = A31_WDOG_CONFIG;
168		sc->wdog_config_value = A31_WDOG_CONFIG_RST_EN_SYSTEM;
169		break;
170	default:
171		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->res);
172		return (ENXIO);
173	}
174
175	mtx_init(&sc->mtx, "AW Watchdog", "aw_wdog", MTX_DEF);
176	EVENTHANDLER_REGISTER(watchdog_list, aw_wdog_watchdog_fn, sc, 0);
177	EVENTHANDLER_REGISTER(shutdown_final, aw_wdog_shutdown_fn, sc,
178	    SHUTDOWN_PRI_LAST - 1);
179
180	return (0);
181}
182
183static void
184aw_wdog_watchdog_fn(void *private, u_int cmd, int *error)
185{
186	struct aw_wdog_softc *sc;
187	uint64_t ms;
188	int i;
189
190	sc = private;
191	mtx_lock(&sc->mtx);
192
193	cmd &= WD_INTERVAL;
194
195	if (cmd > 0) {
196		ms = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000;
197		i = 0;
198		while (wd_intervals[i].milliseconds &&
199		    (ms > wd_intervals[i].milliseconds))
200			i++;
201		if (wd_intervals[i].milliseconds) {
202			WRITE(sc, sc->wdog_mode,
203			  (wd_intervals[i].value << sc->wdog_mode_intvl_shift) |
204			    sc->wdog_mode_en);
205			WRITE(sc, sc->wdog_ctrl,
206			    WDOG_CTRL_RESTART | sc->wdog_ctrl_key);
207			if (sc->wdog_config)
208				WRITE(sc, sc->wdog_config,
209				    sc->wdog_config_value);
210			*error = 0;
211		}
212		else {
213			/*
214			 * Can't arm
215			 * disable watchdog as watchdog(9) requires
216			 */
217			device_printf(sc->dev,
218			    "Can't arm, timeout is more than 16 sec\n");
219			mtx_unlock(&sc->mtx);
220			WRITE(sc, sc->wdog_mode, 0);
221			return;
222		}
223	}
224	else
225		WRITE(sc, sc->wdog_mode, 0);
226
227	mtx_unlock(&sc->mtx);
228}
229
230static void
231aw_wdog_shutdown_fn(void *private, int howto)
232{
233	if ((howto & (RB_POWEROFF|RB_HALT)) == 0)
234		aw_wdog_watchdog_reset();
235}
236
237void
238aw_wdog_watchdog_reset(void)
239{
240
241	if (aw_wdog_sc == NULL) {
242		printf("Reset: watchdog device has not been initialized\n");
243		return;
244	}
245
246	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_mode,
247	    (wd_intervals[0].value << aw_wdog_sc->wdog_mode_intvl_shift) |
248	    aw_wdog_sc->wdog_mode_en);
249	if (aw_wdog_sc->wdog_config)
250		WRITE(aw_wdog_sc, aw_wdog_sc->wdog_config,
251		      aw_wdog_sc->wdog_config_value);
252	WRITE(aw_wdog_sc, aw_wdog_sc->wdog_ctrl,
253	    WDOG_CTRL_RESTART | aw_wdog_sc->wdog_ctrl_key);
254	while(1)
255		;
256
257}
258
259static device_method_t aw_wdog_methods[] = {
260	DEVMETHOD(device_probe, aw_wdog_probe),
261	DEVMETHOD(device_attach, aw_wdog_attach),
262
263	DEVMETHOD_END
264};
265
266static driver_t aw_wdog_driver = {
267	"aw_wdog",
268	aw_wdog_methods,
269	sizeof(struct aw_wdog_softc),
270};
271static devclass_t aw_wdog_devclass;
272
273DRIVER_MODULE(aw_wdog, simplebus, aw_wdog_driver, aw_wdog_devclass, 0, 0);
274