1 /* $OpenBSD: wdt.c,v 1.22 2014/12/10 12:27:57 mikeb 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/systm.h> 35 36 #include <machine/bus.h> 37 38 #include <dev/pci/pcivar.h> 39 #include <dev/pci/pcireg.h> 40 #include <dev/pci/pcidevs.h> 41 42 struct wdt_softc { 43 /* wdt_dev must be the first item in the struct */ 44 struct device sc_dev; 45 46 /* feature set: 0 = none 1 = temp, buzzer, etc. */ 47 int sc_features; 48 49 /* device access through bus space */ 50 bus_space_tag_t sc_iot; 51 bus_space_handle_t sc_ioh; 52 }; 53 54 int wdt_probe(struct device *, void *, void *); 55 void wdt_attach(struct device *, struct device *, void *); 56 int wdt_activate(struct device *, int); 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 NULL, wdt_activate 70 }; 71 72 struct cfdriver wdt_cd = { 73 NULL, "wdt", DV_DULL 74 }; 75 76 const struct pci_matchid wdt_devices[] = { 77 { PCI_VENDOR_INDCOMPSRC, PCI_PRODUCT_INDCOMPSRC_WDT50x } 78 }; 79 80 /* 81 * 8254 counter mappings 82 */ 83 #define WDT_8254_TC_LO 0 /* low 16 bits of timeout counter */ 84 #define WDT_8254_TC_HI 1 /* high 16 bits of timeout counter */ 85 #define WDT_8254_BUZZER 2 86 87 /* 88 * WDT500/501 ports 89 */ 90 #define WDT_8254_BASE 0 91 #define WDT_8254_CTL (WDT_8254_BASE + 3) 92 #define WDT_DISABLE_TIMER 7 93 #define WDT_ENABLE_TIMER 7 94 95 /* 96 * WDT501 specific ports 97 */ 98 #define WDT_STATUS_REG 4 99 #define WDT_START_BUZZER 4 100 #define WDT_TEMPERATURE 5 101 #define WDT_STOP_BUZZER 5 102 103 int 104 wdt_probe(struct device *parent, void *match, void *aux) 105 { 106 return (pci_matchbyid((struct pci_attach_args *)aux, wdt_devices, 107 nitems(wdt_devices))); 108 } 109 110 void 111 wdt_attach(struct device *parent, struct device *self, void *aux) 112 { 113 struct wdt_softc *wdt = (struct wdt_softc *)self; 114 struct pci_attach_args *const pa = (struct pci_attach_args *)aux; 115 bus_size_t iosize; 116 117 /* retrieve the I/O region (BAR2) */ 118 if (pci_mapreg_map(pa, 0x18, PCI_MAPREG_TYPE_IO, 0, 119 &wdt->sc_iot, &wdt->sc_ioh, NULL, &iosize, 0) != 0) { 120 printf("%s: couldn't find PCI I/O region\n", 121 wdt->sc_dev.dv_xname); 122 return; 123 } 124 125 /* sanity check I/O size */ 126 if (iosize != (bus_size_t)16) { 127 printf("%s: invalid I/O region size\n", 128 wdt->sc_dev.dv_xname); 129 return; 130 } 131 132 /* initialize the watchdog timer structure */ 133 134 /* check the feature set available */ 135 if (wdt_is501(wdt)) 136 wdt->sc_features = 1; 137 else 138 wdt->sc_features = 0; 139 140 if (wdt->sc_features) { 141 /* 142 * turn off the buzzer, it may have been activated 143 * by a previous timeout 144 */ 145 wdt_buzzer_off(wdt); 146 147 wdt_buzzer_enable(wdt); 148 } 149 150 /* initialize the timer modes and the lower 16-bit counter */ 151 wdt_init_timer(wdt); 152 153 /* 154 * ensure that the watchdog is disabled 155 */ 156 wdt_timer_disable(wdt); 157 158 /* 159 * register with the watchdog framework 160 */ 161 wdog_register(wdt_set_timeout, wdt); 162 } 163 164 int 165 wdt_activate(struct device *self, int act) 166 { 167 switch (act) { 168 case DVACT_POWERDOWN: 169 wdog_shutdown(self); 170 break; 171 } 172 173 return (0); 174 } 175 176 /* 177 * wdt_is501 178 * 179 * Returns non-zero if the card is a 501 model. 180 */ 181 int 182 wdt_is501(struct wdt_softc *wdt) 183 { 184 /* 185 * It makes too much sense to detect the card type 186 * by the device ID, so we have to resort to testing 187 * the presence of a register to determine the type. 188 */ 189 int v = bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_TEMPERATURE); 190 191 /* XXX may not be reliable */ 192 if (v == 0 || v == 0xFF) 193 return(0); 194 195 return(1); 196 } 197 198 /* 199 * wdt_8254_count 200 * 201 * Loads the specified counter with the 16-bit value 'v'. 202 */ 203 void 204 wdt_8254_count(struct wdt_softc *wdt, int counter, u_int16_t v) 205 { 206 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, 207 WDT_8254_BASE + counter, v & 0xFF); 208 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BASE + counter, v >> 8); 209 } 210 211 /* 212 * wdt_8254_mode 213 * 214 * Sets the mode of the specified counter. 215 */ 216 void 217 wdt_8254_mode(struct wdt_softc *wdt, int counter, int mode) 218 { 219 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_CTL, 220 (counter << 6) | 0x30 | (mode << 1)); 221 } 222 223 /* 224 * wdt_set_timeout 225 * 226 * Load the watchdog timer with the specified number of seconds. 227 * Clamp seconds to be in the interval [2; 1800]. 228 */ 229 int 230 wdt_set_timeout(void *self, int seconds) 231 { 232 struct wdt_softc *wdt = (struct wdt_softc *)self; 233 234 u_int16_t v; 235 int s; 236 237 s = splclock(); 238 239 wdt_timer_disable(wdt); 240 241 if (seconds == 0) { 242 splx(s); 243 return (0); 244 } else if (seconds < 2) 245 seconds = 2; 246 else if (seconds > 1800) 247 seconds = 1800; 248 249 /* 8254 has been programmed with a 2ms period */ 250 v = (u_int16_t)seconds * 50; 251 252 /* load the new timeout count */ 253 wdt_8254_count(wdt, WDT_8254_TC_HI, v); 254 255 /* enable the timer */ 256 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_ENABLE_TIMER, 0); 257 258 splx(s); 259 260 return (seconds); 261 } 262 263 /* 264 * wdt_timer_disable 265 * 266 * Disables the watchdog timer and cancels the scheduled (if any) 267 * kernel timeout. 268 */ 269 void 270 wdt_timer_disable(struct wdt_softc *wdt) 271 { 272 (void)bus_space_read_1(wdt->sc_iot, wdt->sc_ioh, WDT_DISABLE_TIMER); 273 } 274 275 /* 276 * wdt_init_timer 277 * 278 * Configure the modes for the watchdog counters and initialize 279 * the low 16-bits of the watchdog counter to have a period of 280 * approximately 1/50th of a second. 281 */ 282 void 283 wdt_init_timer(struct wdt_softc *wdt) 284 { 285 wdt_8254_mode(wdt, WDT_8254_TC_LO, 3); 286 wdt_8254_mode(wdt, WDT_8254_TC_HI, 2); 287 wdt_8254_count(wdt, WDT_8254_TC_LO, 41666); 288 } 289 290 /******************************************************************* 291 * WDT501 specific functions 292 *******************************************************************/ 293 294 /* 295 * wdt_buzzer_off 296 * 297 * Turns the buzzer off. 298 */ 299 void 300 wdt_buzzer_off(struct wdt_softc *wdt) 301 { 302 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_STOP_BUZZER, 0); 303 } 304 305 #ifndef WDT_DISABLE_BUZZER 306 /* 307 * wdt_buzzer_enable 308 * 309 * Enables the buzzer when the watchdog counter expires. 310 */ 311 void 312 wdt_buzzer_enable(struct wdt_softc *wdt) 313 { 314 bus_space_write_1(wdt->sc_iot, wdt->sc_ioh, WDT_8254_BUZZER, 1); 315 wdt_8254_mode(wdt, WDT_8254_BUZZER, 1); 316 } 317 #else 318 /* 319 * wdt_buzzer_disable 320 * 321 * Disables the buzzer from sounding when the watchdog counter 322 * expires. 323 */ 324 void 325 wdt_buzzer_disable(struct wdt_softc *wdt) 326 { 327 wdt_8254_mode(wdt, WDT_8254_BUZZER, 0); 328 } 329 #endif 330