xref: /freebsd/sys/dev/itwd/itwd.c (revision edca4938f74db18d091868237592abbf7e718669)
1*edca4938SAndriy Gapon /*-
2*edca4938SAndriy Gapon  * SPDX-License-Identifier: BSD-2-Clause
3*edca4938SAndriy Gapon  *
4*edca4938SAndriy Gapon  * Copyright (c) 2019 Andriy Gapon
5*edca4938SAndriy Gapon  *
6*edca4938SAndriy Gapon  * Redistribution and use in source and binary forms, with or without
7*edca4938SAndriy Gapon  * modification, are permitted provided that the following conditions
8*edca4938SAndriy Gapon  * are met:
9*edca4938SAndriy Gapon  * 1. Redistributions of source code must retain the above copyright
10*edca4938SAndriy Gapon  *    notice, this list of conditions and the following disclaimer.
11*edca4938SAndriy Gapon  * 2. Redistributions in binary form must reproduce the above copyright
12*edca4938SAndriy Gapon  *    notice, this list of conditions and the following disclaimer in the
13*edca4938SAndriy Gapon  *    documentation and/or other materials provided with the distribution.
14*edca4938SAndriy Gapon  *
15*edca4938SAndriy Gapon  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16*edca4938SAndriy Gapon  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17*edca4938SAndriy Gapon  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18*edca4938SAndriy Gapon  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19*edca4938SAndriy Gapon  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20*edca4938SAndriy Gapon  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21*edca4938SAndriy Gapon  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22*edca4938SAndriy Gapon  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23*edca4938SAndriy Gapon  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24*edca4938SAndriy Gapon  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25*edca4938SAndriy Gapon  * SUCH DAMAGE.
26*edca4938SAndriy Gapon  */
27*edca4938SAndriy Gapon 
28*edca4938SAndriy Gapon #include <sys/cdefs.h>
29*edca4938SAndriy Gapon __FBSDID("$FreeBSD$");
30*edca4938SAndriy Gapon 
31*edca4938SAndriy Gapon #include <sys/param.h>
32*edca4938SAndriy Gapon #include <sys/kernel.h>
33*edca4938SAndriy Gapon #include <sys/bus.h>
34*edca4938SAndriy Gapon #include <sys/eventhandler.h>
35*edca4938SAndriy Gapon #include <sys/module.h>
36*edca4938SAndriy Gapon #include <sys/rman.h>
37*edca4938SAndriy Gapon #include <sys/systm.h>
38*edca4938SAndriy Gapon #include <sys/watchdog.h>
39*edca4938SAndriy Gapon 
40*edca4938SAndriy Gapon #include <dev/superio/superio.h>
41*edca4938SAndriy Gapon 
42*edca4938SAndriy Gapon #include <machine/bus.h>
43*edca4938SAndriy Gapon #include <machine/resource.h>
44*edca4938SAndriy Gapon 
45*edca4938SAndriy Gapon 
46*edca4938SAndriy Gapon struct itwd_softc {
47*edca4938SAndriy Gapon 	eventhandler_tag	wd_ev;
48*edca4938SAndriy Gapon 	void			*intr_handle;
49*edca4938SAndriy Gapon 	struct resource		*intr_res;
50*edca4938SAndriy Gapon 	int			intr_rid;
51*edca4938SAndriy Gapon };
52*edca4938SAndriy Gapon 
53*edca4938SAndriy Gapon static void
54*edca4938SAndriy Gapon wd_func(void *priv, u_int cmd, int *error)
55*edca4938SAndriy Gapon {
56*edca4938SAndriy Gapon 	device_t dev = priv;
57*edca4938SAndriy Gapon 	uint64_t timeout;
58*edca4938SAndriy Gapon 	uint8_t val;
59*edca4938SAndriy Gapon 
60*edca4938SAndriy Gapon 
61*edca4938SAndriy Gapon 	if (cmd != 0) {
62*edca4938SAndriy Gapon 		cmd &= WD_INTERVAL;
63*edca4938SAndriy Gapon 
64*edca4938SAndriy Gapon 		/*
65*edca4938SAndriy Gapon 		 * Convert the requested timeout to seconds.
66*edca4938SAndriy Gapon 		 * If the timeout is smaller than the minimal supported value
67*edca4938SAndriy Gapon 		 * then set it to the minimum.
68*edca4938SAndriy Gapon 		 * TODO This hardware actually supports 64ms resolution
69*edca4938SAndriy Gapon 		 * when bit 5 of 0x72 is set.  Switch to that resolution when
70*edca4938SAndriy Gapon 		 * needed.
71*edca4938SAndriy Gapon 		 */
72*edca4938SAndriy Gapon 		if (cmd >= WD_TO_1SEC)
73*edca4938SAndriy Gapon 			timeout = (uint64_t)1 << (cmd - WD_TO_1SEC);
74*edca4938SAndriy Gapon 		else
75*edca4938SAndriy Gapon 			timeout = 1;
76*edca4938SAndriy Gapon 
77*edca4938SAndriy Gapon 		/* TODO If timeout is greater than maximum value
78*edca4938SAndriy Gapon 		 * that can be specified in seconds, we should
79*edca4938SAndriy Gapon 		 * switch the timer to minutes mode by clearing
80*edca4938SAndriy Gapon 		 * bit 7 of 0x72 (ensure that bit 5 is also cleared).
81*edca4938SAndriy Gapon 		 *
82*edca4938SAndriy Gapon 		 * For now, just disable the timer to honor the
83*edca4938SAndriy Gapon 		 * watchdog(9) protocol.
84*edca4938SAndriy Gapon 		 *
85*edca4938SAndriy Gapon 		 * XXX The timeout actually can be up to 65535 units
86*edca4938SAndriy Gapon 		 * as it is set via two registers 0x73, LSB, and 0x74,
87*edca4938SAndriy Gapon 		 * MSB.  But it is not clear what the protocol for writing
88*edca4938SAndriy Gapon 		 * those two registers is.
89*edca4938SAndriy Gapon 		 */
90*edca4938SAndriy Gapon 		if (timeout <= UINT8_MAX) {
91*edca4938SAndriy Gapon 			val = timeout;
92*edca4938SAndriy Gapon 			*error = 0;
93*edca4938SAndriy Gapon 		} else {
94*edca4938SAndriy Gapon 			/* error left unchanged */
95*edca4938SAndriy Gapon 			val = 0;
96*edca4938SAndriy Gapon 		}
97*edca4938SAndriy Gapon 	} else {
98*edca4938SAndriy Gapon 		val = 0;
99*edca4938SAndriy Gapon 	}
100*edca4938SAndriy Gapon #ifdef DIAGNOSTIC
101*edca4938SAndriy Gapon 	if (bootverbose)
102*edca4938SAndriy Gapon 		device_printf(dev, "setting timeout to %d\n", val);
103*edca4938SAndriy Gapon #endif
104*edca4938SAndriy Gapon 	superio_write(dev, 0x73, val);
105*edca4938SAndriy Gapon 	if (superio_read(dev, 0x73) != val)
106*edca4938SAndriy Gapon 		superio_write(dev, 0x73, val);
107*edca4938SAndriy Gapon }
108*edca4938SAndriy Gapon 
109*edca4938SAndriy Gapon static void
110*edca4938SAndriy Gapon itwd_intr(void *cookie)
111*edca4938SAndriy Gapon {
112*edca4938SAndriy Gapon 	device_t dev = cookie;
113*edca4938SAndriy Gapon 	uint8_t val;
114*edca4938SAndriy Gapon 
115*edca4938SAndriy Gapon 	val = superio_read(dev, 0x71);
116*edca4938SAndriy Gapon 	if (bootverbose)
117*edca4938SAndriy Gapon 		device_printf(dev, "got interrupt, wdt status = %d\n", val & 1);
118*edca4938SAndriy Gapon 	superio_write(dev, 0x71, val & ~((uint8_t)0x01));
119*edca4938SAndriy Gapon }
120*edca4938SAndriy Gapon 
121*edca4938SAndriy Gapon static int
122*edca4938SAndriy Gapon itwd_probe(device_t dev)
123*edca4938SAndriy Gapon {
124*edca4938SAndriy Gapon 
125*edca4938SAndriy Gapon 	if (superio_vendor(dev) != SUPERIO_VENDOR_ITE)
126*edca4938SAndriy Gapon 		return (ENXIO);
127*edca4938SAndriy Gapon 	if (superio_get_type(dev) != SUPERIO_DEV_WDT)
128*edca4938SAndriy Gapon 		return (ENXIO);
129*edca4938SAndriy Gapon 	device_set_desc(dev, "Watchdog Timer on ITE SuperIO");
130*edca4938SAndriy Gapon 	return (BUS_PROBE_DEFAULT);
131*edca4938SAndriy Gapon }
132*edca4938SAndriy Gapon 
133*edca4938SAndriy Gapon static int
134*edca4938SAndriy Gapon itwd_attach(device_t dev)
135*edca4938SAndriy Gapon {
136*edca4938SAndriy Gapon 	struct itwd_softc *sc = device_get_softc(dev);
137*edca4938SAndriy Gapon 	int irq = 0;
138*edca4938SAndriy Gapon 	int nmi = 0;
139*edca4938SAndriy Gapon 	int error;
140*edca4938SAndriy Gapon 
141*edca4938SAndriy Gapon 	/* First, reset the timeout, just in case. */
142*edca4938SAndriy Gapon 	superio_write(dev, 0x74, 0);
143*edca4938SAndriy Gapon 	superio_write(dev, 0x73, 0);
144*edca4938SAndriy Gapon 
145*edca4938SAndriy Gapon 	TUNABLE_INT_FETCH("dev.itwd.irq", &irq);
146*edca4938SAndriy Gapon 	TUNABLE_INT_FETCH("dev.itwd.nmi", &nmi);
147*edca4938SAndriy Gapon 	if (irq < 0 || irq > 15) {
148*edca4938SAndriy Gapon 		device_printf(dev, "Ignoring invalid IRQ value %d\n", irq);
149*edca4938SAndriy Gapon 		irq = 0;
150*edca4938SAndriy Gapon 	}
151*edca4938SAndriy Gapon 	if (irq == 0 && nmi) {
152*edca4938SAndriy Gapon 		device_printf(dev, "Ignoring NMI mode if IRQ is not set\n");
153*edca4938SAndriy Gapon 		nmi = 0;
154*edca4938SAndriy Gapon 	}
155*edca4938SAndriy Gapon 
156*edca4938SAndriy Gapon 	/*
157*edca4938SAndriy Gapon 	 * NB: if the interrupt has been configured for the NMI delivery,
158*edca4938SAndriy Gapon 	 * then it is not available for the regular interrupt allocation.
159*edca4938SAndriy Gapon 	 * Thus, we configure the hardware to generate the interrupt,
160*edca4938SAndriy Gapon 	 * but do not attempt to allocate and setup it as a regular
161*edca4938SAndriy Gapon 	 * interrupt.
162*edca4938SAndriy Gapon 	 */
163*edca4938SAndriy Gapon 	if (irq != 0 && !nmi) {
164*edca4938SAndriy Gapon 		sc->intr_rid = 0;
165*edca4938SAndriy Gapon 		bus_set_resource(dev, SYS_RES_IRQ, sc->intr_rid, irq, 1);
166*edca4938SAndriy Gapon 
167*edca4938SAndriy Gapon 		sc->intr_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
168*edca4938SAndriy Gapon 		    &sc->intr_rid, RF_ACTIVE);
169*edca4938SAndriy Gapon 		if (sc->intr_res == NULL) {
170*edca4938SAndriy Gapon 			device_printf(dev, "unable to map interrupt\n");
171*edca4938SAndriy Gapon 			return (ENXIO);
172*edca4938SAndriy Gapon 		}
173*edca4938SAndriy Gapon 		error = bus_setup_intr(dev, sc->intr_res,
174*edca4938SAndriy Gapon 		    INTR_TYPE_MISC | INTR_MPSAFE, NULL, itwd_intr, dev,
175*edca4938SAndriy Gapon 		    &sc->intr_handle);
176*edca4938SAndriy Gapon 		if (error != 0) {
177*edca4938SAndriy Gapon 			bus_release_resource(dev, SYS_RES_IRQ,
178*edca4938SAndriy Gapon 			    sc->intr_rid, sc->intr_res);
179*edca4938SAndriy Gapon 			device_printf(dev, "Unable to setup irq: error %d\n",
180*edca4938SAndriy Gapon 			    error);
181*edca4938SAndriy Gapon 			return (ENXIO);
182*edca4938SAndriy Gapon 		}
183*edca4938SAndriy Gapon 	}
184*edca4938SAndriy Gapon 	if (irq != 0) {
185*edca4938SAndriy Gapon 		device_printf(dev, "Using IRQ%d to signal timeout\n", irq);
186*edca4938SAndriy Gapon 	} else {
187*edca4938SAndriy Gapon 		/* System reset via KBRST. */
188*edca4938SAndriy Gapon 		irq = 0x40;
189*edca4938SAndriy Gapon 		device_printf(dev, "Configured for system reset on timeout\n");
190*edca4938SAndriy Gapon 	}
191*edca4938SAndriy Gapon 
192*edca4938SAndriy Gapon 	superio_write(dev, 0x71, 0);
193*edca4938SAndriy Gapon 	superio_write(dev, 0x72, 0x80 | (uint8_t)irq);
194*edca4938SAndriy Gapon 
195*edca4938SAndriy Gapon 	sc->wd_ev = EVENTHANDLER_REGISTER(watchdog_list, wd_func, dev, 0);
196*edca4938SAndriy Gapon 	return (0);
197*edca4938SAndriy Gapon }
198*edca4938SAndriy Gapon 
199*edca4938SAndriy Gapon static int
200*edca4938SAndriy Gapon itwd_detach(device_t dev)
201*edca4938SAndriy Gapon {
202*edca4938SAndriy Gapon 	struct itwd_softc *sc = device_get_softc(dev);
203*edca4938SAndriy Gapon 	int dummy;
204*edca4938SAndriy Gapon 
205*edca4938SAndriy Gapon 	if (sc->wd_ev != NULL)
206*edca4938SAndriy Gapon 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->wd_ev);
207*edca4938SAndriy Gapon 	wd_func(dev, 0, &dummy);
208*edca4938SAndriy Gapon 	if (sc->intr_handle)
209*edca4938SAndriy Gapon 		bus_teardown_intr(dev, sc->intr_res, sc->intr_handle);
210*edca4938SAndriy Gapon 	if (sc->intr_res)
211*edca4938SAndriy Gapon 		bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid,
212*edca4938SAndriy Gapon 		    sc->intr_res);
213*edca4938SAndriy Gapon 	return (0);
214*edca4938SAndriy Gapon }
215*edca4938SAndriy Gapon 
216*edca4938SAndriy Gapon static device_method_t itwd_methods[] = {
217*edca4938SAndriy Gapon 	/* Methods from the device interface */
218*edca4938SAndriy Gapon 	DEVMETHOD(device_probe,		itwd_probe),
219*edca4938SAndriy Gapon 	DEVMETHOD(device_attach,	itwd_attach),
220*edca4938SAndriy Gapon 	DEVMETHOD(device_detach,	itwd_detach),
221*edca4938SAndriy Gapon 
222*edca4938SAndriy Gapon 	/* Terminate method list */
223*edca4938SAndriy Gapon 	{ 0, 0 }
224*edca4938SAndriy Gapon };
225*edca4938SAndriy Gapon 
226*edca4938SAndriy Gapon static driver_t itwd_driver = {
227*edca4938SAndriy Gapon 	"itwd",
228*edca4938SAndriy Gapon 	itwd_methods,
229*edca4938SAndriy Gapon 	sizeof (struct itwd_softc)
230*edca4938SAndriy Gapon };
231*edca4938SAndriy Gapon 
232*edca4938SAndriy Gapon static devclass_t itwd_devclass;
233*edca4938SAndriy Gapon 
234*edca4938SAndriy Gapon DRIVER_MODULE(itwd, superio, itwd_driver, itwd_devclass, NULL, NULL);
235*edca4938SAndriy Gapon MODULE_DEPEND(itwd, superio, 1, 1, 1);
236*edca4938SAndriy Gapon MODULE_VERSION(itwd, 1);
237