1 /*- 2 * Copyright (c) 2000, 2001 Michael Smith 3 * Copyright (c) 2000 BSDi 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 #include "opt_acpi.h" 30 #include <sys/param.h> 31 #include <sys/bus.h> 32 #include <sys/eventhandler.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/sysctl.h> 36 #include <sys/timetc.h> 37 #include <sys/power.h> 38 39 #include <machine/bus.h> 40 #include <machine/resource.h> 41 #include <sys/rman.h> 42 43 #include <contrib/dev/acpica/include/acpi.h> 44 #include <contrib/dev/acpica/include/accommon.h> 45 46 #include <dev/acpica/acpivar.h> 47 #include <dev/pci/pcivar.h> 48 49 /* 50 * A timecounter based on the free-running ACPI timer. 51 * 52 * Based on the i386-only mp_clock.c by <phk@FreeBSD.ORG>. 53 */ 54 55 /* Hooks for the ACPI CA debugging infrastructure */ 56 #define _COMPONENT ACPI_TIMER 57 ACPI_MODULE_NAME("TIMER") 58 59 static device_t acpi_timer_dev; 60 static struct resource *acpi_timer_reg; 61 static bus_space_handle_t acpi_timer_bsh; 62 static bus_space_tag_t acpi_timer_bst; 63 static eventhandler_tag acpi_timer_eh; 64 65 static u_int acpi_timer_frequency = 14318182 / 4; 66 67 /* Knob to disable acpi_timer device */ 68 bool acpi_timer_disabled = false; 69 70 static void acpi_timer_identify(driver_t *driver, device_t parent); 71 static int acpi_timer_probe(device_t dev); 72 static int acpi_timer_attach(device_t dev); 73 static void acpi_timer_resume_handler(struct timecounter *, 74 enum power_stype); 75 static void acpi_timer_suspend_handler(struct timecounter *, 76 enum power_stype); 77 static u_int acpi_timer_get_timecount(struct timecounter *tc); 78 static u_int acpi_timer_get_timecount_safe(struct timecounter *tc); 79 static int acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS); 80 81 static device_method_t acpi_timer_methods[] = { 82 DEVMETHOD(device_identify, acpi_timer_identify), 83 DEVMETHOD(device_probe, acpi_timer_probe), 84 DEVMETHOD(device_attach, acpi_timer_attach), 85 86 DEVMETHOD_END 87 }; 88 89 static driver_t acpi_timer_driver = { 90 "acpi_timer", 91 acpi_timer_methods, 92 0, 93 }; 94 95 DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, 0, 0); 96 MODULE_DEPEND(acpi_timer, acpi, 1, 1, 1); 97 98 static struct timecounter acpi_timer_timecounter = { 99 acpi_timer_get_timecount_safe, /* get_timecount function */ 100 0, /* no poll_pps */ 101 0, /* no default counter_mask */ 102 0, /* no default frequency */ 103 "ACPI", /* name */ 104 -1 /* quality (chosen later) */ 105 }; 106 107 static __inline uint32_t 108 acpi_timer_read(void) 109 { 110 111 return (bus_space_read_4(acpi_timer_bst, acpi_timer_bsh, 0)); 112 } 113 114 /* 115 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources 116 * we will be using. 117 */ 118 static void 119 acpi_timer_identify(driver_t *driver, device_t parent) 120 { 121 device_t dev; 122 rman_res_t rlen, rstart; 123 int rid, rtype; 124 125 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 126 127 if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) || 128 acpi_timer_dev || acpi_timer_disabled || 129 AcpiGbl_FADT.PmTimerLength == 0) 130 return_VOID; 131 132 if ((dev = BUS_ADD_CHILD(parent, 2, "acpi_timer", 0)) == NULL) { 133 device_printf(parent, "could not add acpi_timer0\n"); 134 return_VOID; 135 } 136 acpi_timer_dev = dev; 137 138 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 139 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 140 rtype = SYS_RES_MEMORY; 141 break; 142 case ACPI_ADR_SPACE_SYSTEM_IO: 143 rtype = SYS_RES_IOPORT; 144 break; 145 default: 146 return_VOID; 147 } 148 rid = 0; 149 rlen = AcpiGbl_FADT.PmTimerLength; 150 rstart = AcpiGbl_FADT.XPmTimerBlock.Address; 151 if (bus_set_resource(dev, rtype, rid, rstart, rlen)) 152 device_printf(dev, "couldn't set resource (%s 0x%jx+0x%jx)\n", 153 (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen); 154 return_VOID; 155 } 156 157 static int 158 acpi_timer_probe(device_t dev) 159 { 160 int rid, rtype; 161 162 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 163 164 if (dev != acpi_timer_dev) 165 return (ENXIO); 166 167 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 168 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 169 rtype = SYS_RES_MEMORY; 170 break; 171 case ACPI_ADR_SPACE_SYSTEM_IO: 172 rtype = SYS_RES_IOPORT; 173 break; 174 default: 175 return (ENXIO); 176 } 177 rid = 0; 178 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE); 179 if (acpi_timer_reg == NULL) { 180 device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n", 181 (rtype == SYS_RES_IOPORT) ? "port" : "mem", 182 (u_long)AcpiGbl_FADT.XPmTimerBlock.Address); 183 return (ENXIO); 184 } 185 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg); 186 acpi_timer_bst = rman_get_bustag(acpi_timer_reg); 187 if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) 188 acpi_timer_timecounter.tc_counter_mask = 0xffffffff; 189 else 190 acpi_timer_timecounter.tc_counter_mask = 0x00ffffff; 191 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency; 192 acpi_timer_timecounter.tc_flags = TC_FLAGS_SUSPEND_SAFE; 193 194 acpi_timer_timecounter.tc_name = "ACPI-fast"; 195 acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount; 196 acpi_timer_timecounter.tc_quality = 900; 197 tc_init(&acpi_timer_timecounter); 198 199 device_set_descf(dev, "%d-bit timer at %u.%06uMHz", 200 (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) != 0 ? 32 : 24, 201 acpi_timer_frequency / 1000000, acpi_timer_frequency % 1000000); 202 203 /* Release the resource, we'll allocate it again during attach. */ 204 bus_release_resource(dev, rtype, rid, acpi_timer_reg); 205 return (0); 206 } 207 208 static int 209 acpi_timer_attach(device_t dev) 210 { 211 int rid, rtype; 212 213 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 214 215 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 216 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 217 rtype = SYS_RES_MEMORY; 218 break; 219 case ACPI_ADR_SPACE_SYSTEM_IO: 220 rtype = SYS_RES_IOPORT; 221 break; 222 default: 223 return (ENXIO); 224 } 225 rid = 0; 226 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE); 227 if (acpi_timer_reg == NULL) 228 return (ENXIO); 229 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg); 230 acpi_timer_bst = rman_get_bustag(acpi_timer_reg); 231 232 /* Register suspend event handler. */ 233 if (EVENTHANDLER_REGISTER(power_suspend, acpi_timer_suspend_handler, 234 &acpi_timer_timecounter, EVENTHANDLER_PRI_LAST) == NULL) 235 device_printf(dev, "failed to register suspend event handler\n"); 236 237 return (0); 238 } 239 240 static void 241 acpi_timer_resume_handler(struct timecounter *newtc, enum power_stype stype) 242 { 243 struct timecounter *tc; 244 245 tc = timecounter; 246 if (tc != newtc) { 247 if (bootverbose) 248 device_printf(acpi_timer_dev, 249 "restoring timecounter, %s -> %s\n", 250 tc->tc_name, newtc->tc_name); 251 (void)newtc->tc_get_timecount(newtc); 252 timecounter = newtc; 253 } 254 } 255 256 static void 257 acpi_timer_suspend_handler(struct timecounter *newtc, enum power_stype stype) 258 { 259 struct timecounter *tc; 260 261 /* Deregister existing resume event handler. */ 262 if (acpi_timer_eh != NULL) { 263 EVENTHANDLER_DEREGISTER(power_resume, acpi_timer_eh); 264 acpi_timer_eh = NULL; 265 } 266 267 if ((timecounter->tc_flags & TC_FLAGS_SUSPEND_SAFE) != 0) { 268 /* 269 * If we are using a suspend safe timecounter, don't 270 * save/restore it across suspend/resume. 271 */ 272 return; 273 } 274 275 KASSERT(newtc == &acpi_timer_timecounter, 276 ("acpi_timer_suspend_handler: wrong timecounter")); 277 278 tc = timecounter; 279 if (tc != newtc) { 280 if (bootverbose) 281 device_printf(acpi_timer_dev, 282 "switching timecounter, %s -> %s\n", 283 tc->tc_name, newtc->tc_name); 284 (void)acpi_timer_read(); 285 (void)acpi_timer_read(); 286 timecounter = newtc; 287 acpi_timer_eh = EVENTHANDLER_REGISTER(power_resume, 288 acpi_timer_resume_handler, tc, EVENTHANDLER_PRI_LAST); 289 } 290 } 291 292 /* 293 * Fetch current time value from reliable hardware. 294 */ 295 static u_int 296 acpi_timer_get_timecount(struct timecounter *tc) 297 { 298 return (acpi_timer_read()); 299 } 300 301 /* 302 * Fetch current time value from hardware that may not correctly 303 * latch the counter. We need to read until we have three monotonic 304 * samples and then use the middle one, otherwise we are not protected 305 * against the fact that the bits can be wrong in two directions. If 306 * we only cared about monosity, two reads would be enough. 307 */ 308 static u_int 309 acpi_timer_get_timecount_safe(struct timecounter *tc) 310 { 311 u_int u1, u2, u3; 312 313 u2 = acpi_timer_read(); 314 u3 = acpi_timer_read(); 315 do { 316 u1 = u2; 317 u2 = u3; 318 u3 = acpi_timer_read(); 319 } while (u1 > u2 || u2 > u3); 320 321 return (u2); 322 } 323 324 /* 325 * Timecounter freqency adjustment interface. 326 */ 327 static int 328 acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS) 329 { 330 int error; 331 u_int freq; 332 333 if (acpi_timer_timecounter.tc_frequency == 0) 334 return (EOPNOTSUPP); 335 freq = acpi_timer_frequency; 336 error = sysctl_handle_int(oidp, &freq, 0, req); 337 if (error == 0 && req->newptr != NULL) { 338 acpi_timer_frequency = freq; 339 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency; 340 } 341 342 return (error); 343 } 344 345 SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq, 346 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 347 acpi_timer_sysctl_freq, "I", 348 "ACPI timer frequency"); 349