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 38 #include <machine/bus.h> 39 #include <machine/resource.h> 40 #include <sys/rman.h> 41 42 #include <contrib/dev/acpica/include/acpi.h> 43 #include <contrib/dev/acpica/include/accommon.h> 44 45 #include <dev/acpica/acpivar.h> 46 #include <dev/pci/pcivar.h> 47 48 /* 49 * A timecounter based on the free-running ACPI timer. 50 * 51 * Based on the i386-only mp_clock.c by <phk@FreeBSD.ORG>. 52 */ 53 54 /* Hooks for the ACPI CA debugging infrastructure */ 55 #define _COMPONENT ACPI_TIMER 56 ACPI_MODULE_NAME("TIMER") 57 58 static device_t acpi_timer_dev; 59 static struct resource *acpi_timer_reg; 60 static bus_space_handle_t acpi_timer_bsh; 61 static bus_space_tag_t acpi_timer_bst; 62 static eventhandler_tag acpi_timer_eh; 63 64 static u_int acpi_timer_frequency = 14318182 / 4; 65 66 /* Knob to disable acpi_timer device */ 67 bool acpi_timer_disabled = false; 68 69 static void acpi_timer_identify(driver_t *driver, device_t parent); 70 static int acpi_timer_probe(device_t dev); 71 static int acpi_timer_attach(device_t dev); 72 static void acpi_timer_resume_handler(struct timecounter *); 73 static void acpi_timer_suspend_handler(struct timecounter *); 74 static u_int acpi_timer_get_timecount(struct timecounter *tc); 75 static u_int acpi_timer_get_timecount_safe(struct timecounter *tc); 76 static int acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS); 77 78 static device_method_t acpi_timer_methods[] = { 79 DEVMETHOD(device_identify, acpi_timer_identify), 80 DEVMETHOD(device_probe, acpi_timer_probe), 81 DEVMETHOD(device_attach, acpi_timer_attach), 82 83 DEVMETHOD_END 84 }; 85 86 static driver_t acpi_timer_driver = { 87 "acpi_timer", 88 acpi_timer_methods, 89 0, 90 }; 91 92 DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, 0, 0); 93 MODULE_DEPEND(acpi_timer, acpi, 1, 1, 1); 94 95 static struct timecounter acpi_timer_timecounter = { 96 acpi_timer_get_timecount_safe, /* get_timecount function */ 97 0, /* no poll_pps */ 98 0, /* no default counter_mask */ 99 0, /* no default frequency */ 100 "ACPI", /* name */ 101 -1 /* quality (chosen later) */ 102 }; 103 104 static __inline uint32_t 105 acpi_timer_read(void) 106 { 107 108 return (bus_space_read_4(acpi_timer_bst, acpi_timer_bsh, 0)); 109 } 110 111 /* 112 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources 113 * we will be using. 114 */ 115 static void 116 acpi_timer_identify(driver_t *driver, device_t parent) 117 { 118 device_t dev; 119 rman_res_t rlen, rstart; 120 int rid, rtype; 121 122 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 123 124 if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) || 125 acpi_timer_dev || acpi_timer_disabled || 126 AcpiGbl_FADT.PmTimerLength == 0) 127 return_VOID; 128 129 if ((dev = BUS_ADD_CHILD(parent, 2, "acpi_timer", 0)) == NULL) { 130 device_printf(parent, "could not add acpi_timer0\n"); 131 return_VOID; 132 } 133 acpi_timer_dev = dev; 134 135 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 136 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 137 rtype = SYS_RES_MEMORY; 138 break; 139 case ACPI_ADR_SPACE_SYSTEM_IO: 140 rtype = SYS_RES_IOPORT; 141 break; 142 default: 143 return_VOID; 144 } 145 rid = 0; 146 rlen = AcpiGbl_FADT.PmTimerLength; 147 rstart = AcpiGbl_FADT.XPmTimerBlock.Address; 148 if (bus_set_resource(dev, rtype, rid, rstart, rlen)) 149 device_printf(dev, "couldn't set resource (%s 0x%jx+0x%jx)\n", 150 (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen); 151 return_VOID; 152 } 153 154 static int 155 acpi_timer_probe(device_t dev) 156 { 157 int rid, rtype; 158 159 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 160 161 if (dev != acpi_timer_dev) 162 return (ENXIO); 163 164 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 165 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 166 rtype = SYS_RES_MEMORY; 167 break; 168 case ACPI_ADR_SPACE_SYSTEM_IO: 169 rtype = SYS_RES_IOPORT; 170 break; 171 default: 172 return (ENXIO); 173 } 174 rid = 0; 175 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE); 176 if (acpi_timer_reg == NULL) { 177 device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n", 178 (rtype == SYS_RES_IOPORT) ? "port" : "mem", 179 (u_long)AcpiGbl_FADT.XPmTimerBlock.Address); 180 return (ENXIO); 181 } 182 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg); 183 acpi_timer_bst = rman_get_bustag(acpi_timer_reg); 184 if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) 185 acpi_timer_timecounter.tc_counter_mask = 0xffffffff; 186 else 187 acpi_timer_timecounter.tc_counter_mask = 0x00ffffff; 188 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency; 189 acpi_timer_timecounter.tc_flags = TC_FLAGS_SUSPEND_SAFE; 190 191 acpi_timer_timecounter.tc_name = "ACPI-fast"; 192 acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount; 193 acpi_timer_timecounter.tc_quality = 900; 194 tc_init(&acpi_timer_timecounter); 195 196 device_set_descf(dev, "%d-bit timer at %u.%06uMHz", 197 (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) != 0 ? 32 : 24, 198 acpi_timer_frequency / 1000000, acpi_timer_frequency % 1000000); 199 200 /* Release the resource, we'll allocate it again during attach. */ 201 bus_release_resource(dev, rtype, rid, acpi_timer_reg); 202 return (0); 203 } 204 205 static int 206 acpi_timer_attach(device_t dev) 207 { 208 int rid, rtype; 209 210 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 211 212 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) { 213 case ACPI_ADR_SPACE_SYSTEM_MEMORY: 214 rtype = SYS_RES_MEMORY; 215 break; 216 case ACPI_ADR_SPACE_SYSTEM_IO: 217 rtype = SYS_RES_IOPORT; 218 break; 219 default: 220 return (ENXIO); 221 } 222 rid = 0; 223 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE); 224 if (acpi_timer_reg == NULL) 225 return (ENXIO); 226 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg); 227 acpi_timer_bst = rman_get_bustag(acpi_timer_reg); 228 229 /* Register suspend event handler. */ 230 if (EVENTHANDLER_REGISTER(power_suspend, acpi_timer_suspend_handler, 231 &acpi_timer_timecounter, EVENTHANDLER_PRI_LAST) == NULL) 232 device_printf(dev, "failed to register suspend event handler\n"); 233 234 return (0); 235 } 236 237 static void 238 acpi_timer_resume_handler(struct timecounter *newtc) 239 { 240 struct timecounter *tc; 241 242 tc = timecounter; 243 if (tc != newtc) { 244 if (bootverbose) 245 device_printf(acpi_timer_dev, 246 "restoring timecounter, %s -> %s\n", 247 tc->tc_name, newtc->tc_name); 248 (void)newtc->tc_get_timecount(newtc); 249 timecounter = newtc; 250 } 251 } 252 253 static void 254 acpi_timer_suspend_handler(struct timecounter *newtc) 255 { 256 struct timecounter *tc; 257 258 /* Deregister existing resume event handler. */ 259 if (acpi_timer_eh != NULL) { 260 EVENTHANDLER_DEREGISTER(power_resume, acpi_timer_eh); 261 acpi_timer_eh = NULL; 262 } 263 264 if ((timecounter->tc_flags & TC_FLAGS_SUSPEND_SAFE) != 0) { 265 /* 266 * If we are using a suspend safe timecounter, don't 267 * save/restore it across suspend/resume. 268 */ 269 return; 270 } 271 272 KASSERT(newtc == &acpi_timer_timecounter, 273 ("acpi_timer_suspend_handler: wrong timecounter")); 274 275 tc = timecounter; 276 if (tc != newtc) { 277 if (bootverbose) 278 device_printf(acpi_timer_dev, 279 "switching timecounter, %s -> %s\n", 280 tc->tc_name, newtc->tc_name); 281 (void)acpi_timer_read(); 282 (void)acpi_timer_read(); 283 timecounter = newtc; 284 acpi_timer_eh = EVENTHANDLER_REGISTER(power_resume, 285 acpi_timer_resume_handler, tc, EVENTHANDLER_PRI_LAST); 286 } 287 } 288 289 /* 290 * Fetch current time value from reliable hardware. 291 */ 292 static u_int 293 acpi_timer_get_timecount(struct timecounter *tc) 294 { 295 return (acpi_timer_read()); 296 } 297 298 /* 299 * Fetch current time value from hardware that may not correctly 300 * latch the counter. We need to read until we have three monotonic 301 * samples and then use the middle one, otherwise we are not protected 302 * against the fact that the bits can be wrong in two directions. If 303 * we only cared about monosity, two reads would be enough. 304 */ 305 static u_int 306 acpi_timer_get_timecount_safe(struct timecounter *tc) 307 { 308 u_int u1, u2, u3; 309 310 u2 = acpi_timer_read(); 311 u3 = acpi_timer_read(); 312 do { 313 u1 = u2; 314 u2 = u3; 315 u3 = acpi_timer_read(); 316 } while (u1 > u2 || u2 > u3); 317 318 return (u2); 319 } 320 321 /* 322 * Timecounter freqency adjustment interface. 323 */ 324 static int 325 acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS) 326 { 327 int error; 328 u_int freq; 329 330 if (acpi_timer_timecounter.tc_frequency == 0) 331 return (EOPNOTSUPP); 332 freq = acpi_timer_frequency; 333 error = sysctl_handle_int(oidp, &freq, 0, req); 334 if (error == 0 && req->newptr != NULL) { 335 acpi_timer_frequency = freq; 336 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency; 337 } 338 339 return (error); 340 } 341 342 SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq, 343 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 344 acpi_timer_sysctl_freq, "I", 345 "ACPI timer frequency"); 346