xref: /openbsd/sys/dev/pci/berkwdt.c (revision 9e6efb0a)
1 /*	$OpenBSD: berkwdt.c,v 1.12 2024/05/24 06:02:53 jsg Exp $ */
2 
3 /*
4  * Copyright (c) 2009 Wim Van Sebroeck <wim@iguana.be>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /*
20  * Berkshire PCI-PC Watchdog Card Driver
21  * http://www.pcwatchdog.com/
22  */
23 
24 #include <sys/param.h>
25 #include <sys/device.h>
26 #include <sys/systm.h>
27 
28 #include <machine/bus.h>
29 
30 #include <dev/pci/pcivar.h>
31 #include <dev/pci/pcireg.h>
32 #include <dev/pci/pcidevs.h>
33 
34 struct berkwdt_softc {
35 	struct device	sc_dev;
36 
37 	/* device access through bus space */
38 	bus_space_tag_t		sc_iot;
39 	bus_space_handle_t	sc_ioh;
40 
41 	/* the timeout period */
42 	int		sc_period;
43 };
44 
45 int berkwdt_match(struct device *, void *, void *);
46 void berkwdt_attach(struct device *, struct device *, void *);
47 int berkwdt_activate(struct device *, int);
48 
49 void berkwdt_start(struct berkwdt_softc *sc);
50 void berkwdt_stop(struct berkwdt_softc *sc);
51 void berkwdt_reload(struct berkwdt_softc *sc);
52 int berkwdt_send_command(struct berkwdt_softc *sc, u_int8_t cmd, int *val);
53 
54 int berkwdt_set_timeout(void *, int);
55 
56 const struct cfattach berkwdt_ca = {
57 	sizeof(struct berkwdt_softc), berkwdt_match, berkwdt_attach,
58 	NULL, berkwdt_activate
59 };
60 
61 struct cfdriver berkwdt_cd = {
62 	NULL, "berkwdt", DV_DULL
63 };
64 
65 const struct pci_matchid berkwdt_devices[] = {
66 	{ PCI_VENDOR_PIJNENBURG, PCI_PRODUCT_PIJNENBURG_PCWD_PCI }
67 };
68 
69 /* PCWD-PCI I/O Port definitions */
70 #define PCWD_PCI_RELOAD		0x00	/* Re-trigger */
71 #define PCWD_PCI_CS1		0x01	/* Control Status 1 */
72 #define PCWD_PCI_CS2		0x02	/* Control Status 2 */
73 #define PCWD_PCI_WDT_DIS	0x03	/* Watchdog Disable */
74 #define PCWD_PCI_LSB		0x04	/* Command / Response */
75 #define PCWD_PCI_MSB		0x05	/* Command/Response LSB */
76 #define PCWD_PCI_CMD		0x06	/* Command/Response MSB */
77 
78 /* Port 1 : Control Status #1 */
79 #define WD_PCI_WTRP		0x01	/* Watchdog Trip status */
80 #define WD_PCI_TTRP		0x04	/* Temperature Trip status */
81 #define WD_PCI_R2DS		0x40	/* Relay 2 Disable Temp-trip reset */
82 
83 /* Port 2 : Control Status #2 */
84 #define WD_PCI_WDIS		0x10	/* Watchdog Disable */
85 #define WD_PCI_WRSP		0x40	/* Watchdog wrote response */
86 
87 /*
88  * According to documentation max. time to process a command for the pci
89  * watchdog card is 100 ms, so we give it 150 ms to do its job.
90  */
91 #define PCI_CMD_TIMEOUT		150
92 
93 /* Watchdog's internal commands */
94 #define CMD_WRITE_WD_TIMEOUT	0x19
95 
96 int
97 berkwdt_send_command(struct berkwdt_softc *sc, u_int8_t cmd, int *val)
98 {
99 	u_int8_t msb;
100 	u_int8_t lsb;
101 	u_int8_t got_response;
102 	int count;
103 
104 	msb = *val / 256;
105 	lsb = *val % 256;
106 
107 	/* Send command with data (data first!) */
108 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_LSB, lsb);
109 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_MSB, msb);
110 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CMD, cmd);
111 
112 	got_response = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS2);
113 	got_response &= WD_PCI_WRSP;
114 	for (count = 0; count < PCI_CMD_TIMEOUT && !got_response; count++) {
115 		delay(1000);
116 		got_response = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS2);
117 		got_response &= WD_PCI_WRSP;
118 	}
119 
120 	if (got_response) {
121 		/* read back response */
122 		lsb = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_LSB);
123 		msb = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_MSB);
124 		*val = (msb << 8) + lsb;
125 
126 		/* clear WRSP bit */
127 		bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CMD);
128 		return 1;
129 	}
130 
131 	return 0;
132 }
133 
134 void
135 berkwdt_start(struct berkwdt_softc *sc)
136 {
137 	u_int8_t reg;
138 
139 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_WDT_DIS, 0x00);
140 	delay(1000);
141 
142 	reg = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS2);
143 	if (reg & WD_PCI_WDIS) {
144 		printf("%s: unable to enable\n", sc->sc_dev.dv_xname);
145 	}
146 }
147 
148 void
149 berkwdt_stop(struct berkwdt_softc *sc)
150 {
151 	u_int8_t reg;
152 
153 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_WDT_DIS, 0xa5);
154 	delay(1000);
155 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_WDT_DIS, 0xa5);
156 	delay(1000);
157 
158 	reg = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS2);
159 	if (!(reg & WD_PCI_WDIS)) {
160 		printf("%s: unable to disable\n", sc->sc_dev.dv_xname);
161 	}
162 }
163 
164 void
165 berkwdt_reload(struct berkwdt_softc *sc)
166 {
167 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_RELOAD, 0x42);
168 }
169 
170 int
171 berkwdt_match(struct device *parent, void *match, void *aux)
172 {
173 	return (pci_matchbyid((struct pci_attach_args *)aux, berkwdt_devices,
174 	    sizeof(berkwdt_devices) / sizeof(berkwdt_devices[0])));
175 }
176 
177 void
178 berkwdt_attach(struct device *parent, struct device *self, void *aux)
179 {
180 	struct berkwdt_softc *sc = (struct berkwdt_softc *)self;
181 	struct pci_attach_args *pa = (struct pci_attach_args *)aux;
182 	bus_size_t iosize;
183 	u_int8_t reg;
184 
185 	/* retrieve the I/O region (BAR 0) */
186 	if (pci_mapreg_map(pa, 0x10, PCI_MAPREG_TYPE_IO, 0,
187 	    &sc->sc_iot, &sc->sc_ioh, NULL, &iosize, 0) != 0) {
188 		printf(": couldn't find PCI I/O region\n");
189 		return;
190 	}
191 
192 	/* Check for reboot by the card */
193 	reg = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS1);
194 	if (reg & WD_PCI_WTRP) {
195 		printf(", warning: watchdog triggered");
196 
197 		if (reg & WD_PCI_TTRP)
198 			printf(", overheat detected");
199 
200 		/* clear trip status & LED and keep mode of relay 2 */
201 		reg &= WD_PCI_R2DS;
202 		reg |= WD_PCI_WTRP;
203 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, PCWD_PCI_CS1, reg);
204 	}
205 
206 	printf("\n");
207 
208 	/* ensure that the watchdog is disabled */
209 	berkwdt_stop(sc);
210 	sc->sc_period = 0;
211 
212 	/* register with the watchdog framework */
213 	wdog_register(berkwdt_set_timeout, sc);
214 }
215 
216 int
217 berkwdt_activate(struct device *self, int act)
218 {
219 	switch (act) {
220 	case DVACT_POWERDOWN:
221 		wdog_shutdown(self);
222 		break;
223 	}
224 
225 	return (0);
226 }
227 
228 int
229 berkwdt_set_timeout(void *self, int timeout)
230 {
231 	struct berkwdt_softc *sc = self;
232 	int new_timeout = timeout;
233 
234 	if (timeout == 0) {
235 		/* Disable watchdog */
236 		berkwdt_stop(sc);
237 	} else {
238 		if (sc->sc_period != timeout) {
239 			/* Set new timeout */
240 			berkwdt_send_command(sc, CMD_WRITE_WD_TIMEOUT,
241 			    &new_timeout);
242 		}
243 		if (sc->sc_period == 0) {
244 			/* Enable watchdog */
245 			berkwdt_start(sc);
246 			berkwdt_reload(sc);
247 		} else {
248 			/* Reset timer */
249 			berkwdt_reload(sc);
250 		}
251 	}
252 	sc->sc_period = timeout;
253 
254 	return (timeout);
255 }
256 
257