1 /*- 2 * Copyright (c) 2005 Poul-Henning Kamp 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/dev/acpica/acpi_hpet.c,v 1.12.2.1.2.1 2008/11/25 02:59:29 kensmith Exp $ 27 */ 28 29 #include "opt_acpi.h" 30 31 #include <sys/param.h> 32 #include <sys/bus.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/systimer.h> 36 #include <sys/rman.h> 37 38 #include "acpi.h" 39 #include "accommon.h" 40 #include "acpivar.h" 41 #include "acpi_hpet.h" 42 43 /* Hooks for the ACPICA debugging infrastructure */ 44 #define _COMPONENT ACPI_TIMER 45 ACPI_MODULE_NAME("HPET") 46 47 static bus_space_handle_t acpi_hpet_bsh; 48 static bus_space_tag_t acpi_hpet_bst; 49 static u_long acpi_hpet_res_start; 50 51 struct acpi_hpet_softc { 52 device_t dev; 53 struct resource *mem_res; 54 ACPI_HANDLE handle; 55 }; 56 57 #define DEV_HPET(x) (acpi_get_magic(x) == (uintptr_t)&acpi_hpet_devclass) 58 59 static sysclock_t acpi_hpet_get_timecount(void); 60 static void acpi_hpet_construct(struct cputimer *, sysclock_t); 61 62 static int acpi_hpet_identify(driver_t *, device_t); 63 static int acpi_hpet_probe(device_t); 64 static int acpi_hpet_attach(device_t); 65 static int acpi_hpet_resume(device_t); 66 static int acpi_hpet_suspend(device_t); 67 68 static void acpi_hpet_test(struct acpi_hpet_softc *sc); 69 static u_int acpi_hpet_read(void); 70 static void acpi_hpet_enable(struct acpi_hpet_softc *); 71 static void acpi_hpet_disable(struct acpi_hpet_softc *); 72 73 static char *hpet_ids[] = { "PNP0103", NULL }; 74 75 static struct cputimer acpi_hpet_timer = { 76 SLIST_ENTRY_INITIALIZER, 77 "HPET", 78 CPUTIMER_PRI_HPET, 79 CPUTIMER_HPET, 80 acpi_hpet_get_timecount, 81 cputimer_default_fromhz, 82 cputimer_default_fromus, 83 acpi_hpet_construct, 84 cputimer_default_destruct, 85 0, 86 0, 0, 0 87 }; 88 89 static device_method_t acpi_hpet_methods[] = { 90 DEVMETHOD(device_identify, acpi_hpet_identify), 91 DEVMETHOD(device_probe, acpi_hpet_probe), 92 DEVMETHOD(device_attach, acpi_hpet_attach), 93 DEVMETHOD(device_suspend, acpi_hpet_suspend), 94 DEVMETHOD(device_resume, acpi_hpet_resume), 95 DEVMETHOD_END 96 }; 97 98 static driver_t acpi_hpet_driver = { 99 "acpi_hpet", 100 acpi_hpet_methods, 101 sizeof(struct acpi_hpet_softc), 102 }; 103 104 static devclass_t acpi_hpet_devclass; 105 DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, NULL, NULL); 106 MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1); 107 108 static u_int 109 acpi_hpet_read(void) 110 { 111 return bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, 112 HPET_MAIN_COUNTER); 113 } 114 115 /* 116 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources 117 * we will be using. 118 */ 119 static int 120 acpi_hpet_identify(driver_t *driver, device_t parent) 121 { 122 ACPI_TABLE_HPET *hpet; 123 ACPI_TABLE_HEADER *hdr; 124 ACPI_STATUS status; 125 device_t child; 126 127 /* 128 * Just try once, do nothing if the 'acpi' bus is rescanned. 129 */ 130 if (device_get_state(parent) == DS_ATTACHED) 131 return 0; 132 133 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 134 135 /* Only one HPET device can be added. */ 136 if (devclass_get_device(acpi_hpet_devclass, 0)) 137 return ENXIO; 138 139 /* Currently, ID and minimum clock tick info is unused. */ 140 141 status = AcpiGetTable(ACPI_SIG_HPET, 1, &hdr); 142 if (ACPI_FAILURE(status)) 143 return ENXIO; 144 145 /* 146 * The unit number could be derived from hdr->Sequence but we only 147 * support one HPET device. 148 */ 149 hpet = (ACPI_TABLE_HPET *)hdr; 150 if (hpet->Sequence != 0) { 151 kprintf("ACPI HPET table warning: Sequence is non-zero (%d)\n", 152 hpet->Sequence); 153 } 154 155 child = BUS_ADD_CHILD(parent, parent, 0, "acpi_hpet", 0); 156 if (child == NULL) { 157 device_printf(parent, "%s: can't add acpi_hpet0\n", __func__); 158 return ENXIO; 159 } 160 161 /* Record a magic value so we can detect this device later. */ 162 acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass); 163 164 acpi_hpet_res_start = hpet->Address.Address; 165 if (bus_set_resource(child, SYS_RES_MEMORY, 0, 166 hpet->Address.Address, HPET_MEM_WIDTH, -1)) { 167 device_printf(child, "could not set iomem resources: " 168 "0x%jx, %d\n", (uintmax_t)hpet->Address.Address, 169 HPET_MEM_WIDTH); 170 return ENOMEM; 171 } 172 return 0; 173 } 174 175 static int 176 acpi_hpet_probe(device_t dev) 177 { 178 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 179 180 if (acpi_disabled("hpet")) 181 return ENXIO; 182 183 if (!DEV_HPET(dev) && 184 (ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL || 185 device_get_unit(dev) != 0)) 186 return ENXIO; 187 188 device_set_desc(dev, "High Precision Event Timer"); 189 return 0; 190 } 191 192 static int 193 acpi_hpet_attach(device_t dev) 194 { 195 struct acpi_hpet_softc *sc; 196 int rid; 197 uint32_t val, val2; 198 uintmax_t freq; 199 200 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 201 202 sc = device_get_softc(dev); 203 sc->dev = dev; 204 sc->handle = acpi_get_handle(dev); 205 206 rid = 0; 207 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 208 RF_ACTIVE); 209 if (sc->mem_res == NULL) { 210 /* 211 * We only need to make sure that main counter 212 * is accessable. 213 */ 214 device_printf(dev, "can't map %dB register space, try %dB\n", 215 HPET_MEM_WIDTH, HPET_MEM_WIDTH_MIN); 216 rid = 0; 217 sc->mem_res = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid, 218 acpi_hpet_res_start, 219 acpi_hpet_res_start + HPET_MEM_WIDTH_MIN - 1, 220 HPET_MEM_WIDTH_MIN, RF_ACTIVE); 221 if (sc->mem_res == NULL) 222 return ENOMEM; 223 } 224 225 /* Validate that we can access the whole region. */ 226 if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH_MIN) { 227 device_printf(dev, "memory region width %ld too small\n", 228 rman_get_size(sc->mem_res)); 229 bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res); 230 return ENXIO; 231 } 232 233 acpi_hpet_bsh = rman_get_bushandle(sc->mem_res); 234 acpi_hpet_bst = rman_get_bustag(sc->mem_res); 235 236 /* Be sure timer is enabled. */ 237 acpi_hpet_enable(sc); 238 239 /* Read basic statistics about the timer. */ 240 val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_PERIOD); 241 if (val == 0) { 242 device_printf(dev, "invalid period\n"); 243 acpi_hpet_disable(sc); 244 bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res); 245 return ENXIO; 246 } 247 248 freq = (1000000000000000LL + val / 2) / val; 249 if (bootverbose) { 250 val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, 251 HPET_CAPABILITIES); 252 device_printf(dev, 253 "vend: 0x%x, rev: 0x%x, num: %d, opts:%s%s\n", 254 val >> 16, val & HPET_CAP_REV_ID, 255 (val & HPET_CAP_NUM_TIM) >> 8, 256 (val & HPET_CAP_LEG_RT) ? " legacy_route" : "", 257 (val & HPET_CAP_COUNT_SIZE) ? " 64-bit" : ""); 258 } 259 260 if (ktestenv("debug.acpi.hpet_test")) 261 acpi_hpet_test(sc); 262 263 /* 264 * Don't attach if the timer never increments. Since the spec 265 * requires it to be at least 10 MHz, it has to change in 1 us. 266 */ 267 val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, 268 HPET_MAIN_COUNTER); 269 DELAY(1); 270 val2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, 271 HPET_MAIN_COUNTER); 272 if (val == val2) { 273 device_printf(dev, "HPET never increments, disabling\n"); 274 acpi_hpet_disable(sc); 275 bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res); 276 return ENXIO; 277 } 278 279 acpi_hpet_timer.freq = freq; 280 device_printf(dev, "frequency %u\n", acpi_hpet_timer.freq); 281 282 cputimer_register(&acpi_hpet_timer); 283 cputimer_select(&acpi_hpet_timer, 0); 284 285 return 0; 286 } 287 288 /* 289 * Construct the timer. Adjust the base so the system clock does not 290 * jump weirdly. 291 */ 292 static void 293 acpi_hpet_construct(struct cputimer *timer, sysclock_t oldclock) 294 { 295 timer->base = 0; 296 timer->base = oldclock - acpi_hpet_get_timecount(); 297 } 298 299 static sysclock_t 300 acpi_hpet_get_timecount(void) 301 { 302 return acpi_hpet_read() + acpi_hpet_timer.base; 303 } 304 305 static void 306 acpi_hpet_enable(struct acpi_hpet_softc *sc) 307 { 308 uint32_t val; 309 310 val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG); 311 bus_space_write_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG, 312 val | HPET_CNF_ENABLE); 313 } 314 315 static void 316 acpi_hpet_disable(struct acpi_hpet_softc *sc) 317 { 318 uint32_t val; 319 320 val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG); 321 bus_space_write_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG, 322 val & ~HPET_CNF_ENABLE); 323 } 324 325 static int 326 acpi_hpet_suspend(device_t dev) 327 { 328 /* 329 * According to IA-PC HPET specification rev 1.0a 330 * 331 * Page 10, 2.3.3: 332 * "1. The Event Timer registers (including the main counter) 333 * are not expected to be preserved through an S3, S4, or S5 334 * state." 335 * 336 * Page 11, 2.3.3: 337 * "3. The main counter is permitted, but not required, to run 338 * during S1 or S2 states. ..." 339 * 340 * These mean we are not allowed to enter any of Sx states, 341 * if HPET is used as the sys_cputimer. 342 */ 343 if (sys_cputimer != &acpi_hpet_timer) { 344 struct acpi_hpet_softc *sc; 345 346 sc = device_get_softc(dev); 347 acpi_hpet_disable(sc); 348 349 return 0; 350 } else { 351 return EOPNOTSUPP; 352 } 353 } 354 355 static int 356 acpi_hpet_resume(device_t dev) 357 { 358 if (sys_cputimer != &acpi_hpet_timer) { 359 struct acpi_hpet_softc *sc; 360 361 sc = device_get_softc(dev); 362 acpi_hpet_enable(sc); 363 } 364 return 0; 365 } 366 367 /* Print some basic latency/rate information to assist in debugging. */ 368 static void 369 acpi_hpet_test(struct acpi_hpet_softc *sc) 370 { 371 int i; 372 uint32_t u1, u2; 373 struct timeval b0, b1, b2; 374 struct timespec ts; 375 376 microuptime(&b0); 377 microuptime(&b0); 378 microuptime(&b1); 379 u1 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_MAIN_COUNTER); 380 for (i = 1; i < 1000; i++) { 381 u2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, 382 HPET_MAIN_COUNTER); 383 } 384 microuptime(&b2); 385 u2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_MAIN_COUNTER); 386 387 timevalsub(&b2, &b1); 388 timevalsub(&b1, &b0); 389 timevalsub(&b2, &b1); 390 391 TIMEVAL_TO_TIMESPEC(&b2, &ts); 392 393 device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n", 394 (long)b2.tv_sec, b2.tv_usec, u1, u2, u2 - u1); 395 396 device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000); 397 } 398