Annotation of sys/dev/pci/ichwdt.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: ichwdt.c,v 1.2 2005/12/17 21:05:50 grange Exp $ */
2:
3: /*
4: * Copyright (c) 2004, 2005 Alexander Yurchenko <grange@openbsd.org>
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: * Intel 6300ESB ICH watchdog timer driver.
21: */
22:
23: #include <sys/param.h>
24: #include <sys/systm.h>
25: #include <sys/device.h>
26:
27: #include <machine/bus.h>
28:
29: #include <dev/pci/pcireg.h>
30: #include <dev/pci/pcivar.h>
31: #include <dev/pci/pcidevs.h>
32:
33: #include <dev/pci/ichreg.h>
34:
35: #ifdef ICHWDT_DEBUG
36: #define DPRINTF(x) printf x
37: #else
38: #define DPRINTF(x)
39: #endif
40:
41: struct ichwdt_softc {
42: struct device sc_dev;
43:
44: pci_chipset_tag_t sc_pc;
45: pcitag_t sc_tag;
46:
47: bus_space_tag_t sc_iot;
48: bus_space_handle_t sc_ioh;
49:
50: int sc_divisor;
51: int sc_period;
52: };
53:
54: int ichwdt_match(struct device *, void *, void *);
55: void ichwdt_attach(struct device *, struct device *, void *);
56:
57: int ichwdt_cb(void *, int);
58:
59: struct cfattach ichwdt_ca = {
60: sizeof(struct ichwdt_softc),
61: ichwdt_match,
62: ichwdt_attach
63: };
64:
65: struct cfdriver ichwdt_cd = {
66: NULL, "ichwdt", DV_DULL
67: };
68:
69: const struct pci_matchid ichwdt_devices[] = {
70: { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_6300ESB_WDT }
71: };
72:
73: static __inline void
74: ichwdt_unlock_write(struct ichwdt_softc *sc, int reg, u_int32_t val)
75: {
76: /* Register unlocking sequence */
77: bus_space_write_4(sc->sc_iot, sc->sc_ioh, ICH_WDT_RELOAD, 0x80);
78: bus_space_write_4(sc->sc_iot, sc->sc_ioh, ICH_WDT_RELOAD, 0x86);
79:
80: /* Now it's possible to write to the register */
81: bus_space_write_4(sc->sc_iot, sc->sc_ioh, reg, val);
82: }
83:
84: int
85: ichwdt_match(struct device *parent, void *match, void *aux)
86: {
87: return (pci_matchbyid((struct pci_attach_args *)aux, ichwdt_devices,
88: sizeof(ichwdt_devices) / sizeof(ichwdt_devices[0])));
89: }
90:
91: void
92: ichwdt_attach(struct device *parent, struct device *self, void *aux)
93: {
94: struct ichwdt_softc *sc = (struct ichwdt_softc *)self;
95: struct pci_attach_args *pa = aux;
96: u_int32_t reg;
97:
98: sc->sc_pc = pa->pa_pc;
99: sc->sc_tag = pa->pa_tag;
100:
101: /* Map memory space */
102: sc->sc_iot = pa->pa_iot;
103: if (pci_mapreg_map(pa, ICH_WDT_BASE, PCI_MAPREG_TYPE_MEM, 0,
104: &sc->sc_iot, &sc->sc_ioh, NULL, NULL, 0)) {
105: printf(": failed to map memory space\n");
106: return;
107: }
108:
109: /* Read current configuration */
110: reg = pci_conf_read(sc->sc_pc, sc->sc_tag, ICH_WDT_CONF);
111: DPRINTF((": conf 0x%x", reg));
112:
113: /* Get clock divisor */
114: sc->sc_divisor = (reg & ICH_WDT_CONF_PRE ? 32 : 32768);
115: printf(": %s clock", (reg & ICH_WDT_CONF_PRE ? "1MHz" : "1kHz"));
116:
117: /* Disable interrupts since we don't use first stage timeout alarm */
118: reg &= ~ICH_WDT_CONF_INT_MASK;
119: reg |= ICH_WDT_CONF_INT_DIS;
120: pci_conf_write(sc->sc_pc, sc->sc_tag, ICH_WDT_CONF, reg);
121:
122: /* Check for reboot on timeout */
123: reg = bus_space_read_4(sc->sc_iot, sc->sc_ioh, ICH_WDT_RELOAD);
124: if (reg & ICH_WDT_RELOAD_TIMEOUT) {
125: printf(": reboot on timeout");
126:
127: /* Clear timeout bit */
128: ichwdt_unlock_write(sc, ICH_WDT_RELOAD,
129: ICH_WDT_RELOAD_TIMEOUT);
130: }
131:
132: /* Disable watchdog */
133: pci_conf_write(sc->sc_pc, sc->sc_tag, ICH_WDT_LOCK, 0);
134: sc->sc_period = 0;
135:
136: printf("\n");
137:
138: /* Register new watchdog */
139: wdog_register(sc, ichwdt_cb);
140: }
141:
142: int
143: ichwdt_cb(void *arg, int period)
144: {
145: struct ichwdt_softc *sc = arg;
146: int ticks;
147:
148: if (period == 0) {
149: if (sc->sc_period != 0) {
150: /* Disable watchdog */
151: ichwdt_unlock_write(sc, ICH_WDT_RELOAD,
152: ICH_WDT_RELOAD_RLD);
153: pci_conf_write(sc->sc_pc, sc->sc_tag, ICH_WDT_LOCK, 0);
154: DPRINTF(("%s: disabled, conf 0x%x\n",
155: sc->sc_dev.dv_xname,
156: pci_conf_read(sc->sc_pc, sc->sc_tag,
157: ICH_WDT_LOCK)));
158: }
159: } else {
160: /* 1000s should be enough for everyone */
161: if (period > 1000)
162: period = 1000;
163:
164: if (sc->sc_period != period) {
165: /* Set new timeout */
166: ticks = (period * 33000000) / sc->sc_divisor;
167: ichwdt_unlock_write(sc, ICH_WDT_PRE1, ticks);
168: ichwdt_unlock_write(sc, ICH_WDT_PRE2, 2);
169: DPRINTF(("%s: timeout %ds (%d ticks)\n",
170: sc->sc_dev.dv_xname, period, ticks));
171: }
172: if (sc->sc_period == 0) {
173: /* Enable watchdog */
174: pci_conf_write(sc->sc_pc, sc->sc_tag, ICH_WDT_LOCK,
175: ICH_WDT_LOCK_ENABLED);
176: DPRINTF(("%s: enabled, conf 0x%x\n",
177: sc->sc_dev.dv_xname,
178: pci_conf_read(sc->sc_pc, sc->sc_tag,
179: ICH_WDT_LOCK)));
180: } else {
181: /* Reset timer */
182: ichwdt_unlock_write(sc, ICH_WDT_RELOAD,
183: ICH_WDT_RELOAD_RLD);
184: DPRINTF(("%s: reloaded\n", sc->sc_dev.dv_xname));
185: }
186: }
187: sc->sc_period = period;
188:
189: return (period);
190: }
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