1 /* $OpenBSD: wdt.c,v 1.18 2009/04/25 17:50:48 mk Exp $ */ 2 3 /*- 4 * Copyright (c) 1998,1999 Alex Nash 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 */ 29 30 #include <sys/types.h> 31 #include <sys/param.h> 32 #include <sys/device.h> 33 #include <sys/kernel.h> 34 #include <sys/proc.h> 35 #include <sys/systm.h> 36 37 #include <machine/bus.h> 38 39 #include <dev/pci/pcivar.h> 40 #include <dev/pci/pcireg.h> 41 #include <dev/pci/pcidevs.h> 42 43 struct wdt_softc { 44 /* wdt_dev must be the first item in the struct */ 45 struct device sc_dev; 46 47 /* feature set: 0 = none 1 = temp, buzzer, etc. */ 48 int sc_features; 49 50 /* device access through bus space */ 51 bus_space_tag_t sc_iot; 52 bus_space_handle_t sc_ioh; 53 }; 54 55 int wdt_probe(struct device *, void *, void *); 56 void wdt_attach(struct device *, struct device *, void *); 57 58 int wdt_is501(struct wdt_softc *); 59 void wdt_8254_count(struct wdt_softc *, int, u_int16_t); 60 void wdt_8254_mode(struct wdt_softc *, int, int); 61 int wdt_set_timeout(void *, int); 62 void wdt_init_timer(struct wdt_softc *); 63 void wdt_buzzer_off(struct wdt_softc *); 64 void wdt_timer_disable(struct wdt_softc *); 65 void wdt_buzzer_enable(struct wdt_softc *); 66 67 struct cfattach wdt_ca = { 68 sizeof(struct wdt_softc), wdt_probe, wdt_attach 69 }; 70 71 struct cfdriver wdt_cd = { 72 NULL, "wdt", DV_DULL 73 }; 74 75 const struct pci_matchid wdt_devices[] = { 76 { PCI_VENDOR_INDCOMPSRC, PCI_PRODUCT_INDCOMPSRC_WDT50x } 77 }; 78 79 /* 80 * 8254 counter mappings 81 */ 82 #define WDT_8254_TC_LO 0 /* low 16 bits of timeout counter */ 83 #define WDT_8254_TC_HI 1 /* high 16 bits of timeout counter */ 84 #define WDT_8254_BUZZER 2 85 86 /* 87 * WDT500/501 ports 88 */ 89 #define WDT_8254_BASE 0 90 #define WDT_8254_CTL (WDT_8254_BASE + 3) 91 #define WDT_DISABLE_TIMER 7 92 #define WDT_ENABLE_TIMER 7 93 94 /* 95 * WDT501 specific ports 96 */ 97 #define WDT_STATUS_REG 4 98 #define WDT_START_BUZZER 4 99 #define WDT_TEMPERATURE 5 100 #define WDT_STOP_BUZZER 5 101 102 int 103 wdt_probe(struct device *parent, void *match, void *aux) 104 { 105 return (pci_matchbyid((struct pci_attach_args *)aux, wdt_devices, 106 sizeof(wdt_devices)/sizeof(wdt_devices[0]))); 107 } 108 109 void 110 wdt_attach(struct device *parent, struct device *self, void *aux) 111 { 112 struct wdt_softc *wdt = (struct wdt_softc *)self; 113 struct pci_attach_args *const pa = (struct pci_attach_args *)aux; 114 bus_size_t iosize; 115 116 /* retrieve the I/O region (BAR2) */ 117 if (pci_mapreg_map(pa, 0x18, PCI_MAPREG_TYPE_IO, 0, 118 &wdt->sc_iot, &wdt->sc_ioh, NULL, &iosize, 0) != 0) { 119 printf("%s: couldn't find PCI I/O region\n", 120 wdt->sc_dev.dv_xname); 121 return; 122 } 123 124 /* sanity check I/O size */ 125 if (iosize != (bus_size_t)16) { 126 printf("%s: invalid I/O region size\n", 127 wdt->sc_dev.dv_xname); 128 return; 129 } 130 131 /* initialize the watchdog timer structure */ 132 133 /* check the feature set available */ 134 if (wdt_is501(wdt)) 135 wdt->sc_features = 1; 136 else 137 wdt->sc_features = 0; 138 139 if (wdt->sc_features) { 140 /* 141 * turn off the buzzer, it may have been activated 142 * by a previous timeout 143 */ 144 wdt_buzzer_off(wdt); 145 146 wdt_buzzer_enable(wdt); 147 } 148 149 /* initialize the timer modes and the lower 16-bit counter */ 150 wdt_init_timer(wdt); 151 152 /* 153 * ensure that the watchdog is disabled 154 */ 155 wdt_timer_disable(wdt); 156 157 /* 158 * register with the watchdog framework 159 */ 160 wdog_register(wdt, wdt_set_timeout); 161 } 162 163 /* 164 * wdt_is501 165 * 166 * Returns non-zero if the card is a 501 model. 167 */ 168 int 169 wdt_is501(struct wdt_softc *wdt) 170 { 171 /* 172 * It makes too much sense to detect the card type 173 * by the device ID, so we have to resort to testing 174 * the presence of a register to determine the type. 175 */ 176 int v = bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_TEMPERATURE); 177 178 /* XXX may not be reliable */ 179 if (v == 0 || v == 0xFF) 180 return(0); 181 182 return(1); 183 } 184 185 /* 186 * wdt_8254_count 187 * 188 * Loads the specified counter with the 16-bit value 'v'. 189 */ 190 void 191 wdt_8254_count(struct wdt_softc *wdt, int counter, u_int16_t v) 192 { 193 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, 194 WDT_8254_BASE + counter, v & 0xFF); 195 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BASE + counter, v >> 8); 196 } 197 198 /* 199 * wdt_8254_mode 200 * 201 * Sets the mode of the specified counter. 202 */ 203 void 204 wdt_8254_mode(struct wdt_softc *wdt, int counter, int mode) 205 { 206 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_CTL, 207 (counter << 6) | 0x30 | (mode << 1)); 208 } 209 210 /* 211 * wdt_set_timeout 212 * 213 * Load the watchdog timer with the specified number of seconds. 214 * Clamp seconds to be in the interval [2; 1800]. 215 */ 216 int 217 wdt_set_timeout(void *self, int seconds) 218 { 219 struct wdt_softc *wdt = (struct wdt_softc *)self; 220 221 u_int16_t v; 222 int s; 223 224 s = splclock(); 225 226 wdt_timer_disable(wdt); 227 228 if (seconds == 0) { 229 splx(s); 230 return (0); 231 } else if (seconds < 2) 232 seconds = 2; 233 else if (seconds > 1800) 234 seconds = 1800; 235 236 /* 8254 has been programmed with a 2ms period */ 237 v = (u_int16_t)seconds * 50; 238 239 /* load the new timeout count */ 240 wdt_8254_count(wdt, WDT_8254_TC_HI, v); 241 242 /* enable the timer */ 243 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_ENABLE_TIMER, 0); 244 245 splx(s); 246 247 return (seconds); 248 } 249 250 /* 251 * wdt_timer_disable 252 * 253 * Disables the watchdog timer and cancels the scheduled (if any) 254 * kernel timeout. 255 */ 256 void 257 wdt_timer_disable(struct wdt_softc *wdt) 258 { 259 (void)bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_DISABLE_TIMER); 260 } 261 262 /* 263 * wdt_init_timer 264 * 265 * Configure the modes for the watchdog counters and initialize 266 * the low 16-bits of the watchdog counter to have a period of 267 * approximately 1/50th of a second. 268 */ 269 void 270 wdt_init_timer(struct wdt_softc *wdt) 271 { 272 wdt_8254_mode(wdt, WDT_8254_TC_LO, 3); 273 wdt_8254_mode(wdt, WDT_8254_TC_HI, 2); 274 wdt_8254_count(wdt, WDT_8254_TC_LO, 41666); 275 } 276 277 /******************************************************************* 278 * WDT501 specific functions 279 *******************************************************************/ 280 281 /* 282 * wdt_buzzer_off 283 * 284 * Turns the buzzer off. 285 */ 286 void 287 wdt_buzzer_off(struct wdt_softc *wdt) 288 { 289 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_STOP_BUZZER, 0); 290 } 291 292 #ifndef WDT_DISABLE_BUZZER 293 /* 294 * wdt_buzzer_enable 295 * 296 * Enables the buzzer when the watchdog counter expires. 297 */ 298 void 299 wdt_buzzer_enable(struct wdt_softc *wdt) 300 { 301 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BUZZER, 1); 302 wdt_8254_mode(wdt, WDT_8254_BUZZER, 1); 303 } 304 #else 305 /* 306 * wdt_buzzer_disable 307 * 308 * Disables the buzzer from sounding when the watchdog counter 309 * expires. 310 */ 311 void 312 wdt_buzzer_disable(struct wdt_softc *wdt) 313 { 314 wdt_8254_mode(wdt, WDT_8254_BUZZER, 0); 315 } 316 #endif 317