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 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_acpi.h" 31 #include <sys/param.h> 32 #include <sys/bus.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/rman.h> 36 #include <sys/time.h> 37 #include <sys/timetc.h> 38 39 #include <contrib/dev/acpica/acpi.h> 40 #include <dev/acpica/acpivar.h> 41 42 ACPI_SERIAL_DECL(hpet, "ACPI HPET support"); 43 44 static devclass_t acpi_hpet_devclass; 45 46 /* ACPI CA debugging */ 47 #define _COMPONENT ACPI_TIMER 48 ACPI_MODULE_NAME("HPET") 49 50 struct acpi_hpet_softc { 51 device_t dev; 52 struct resource *mem_res; 53 ACPI_HANDLE handle; 54 }; 55 56 static u_int hpet_get_timecount(struct timecounter *tc); 57 static void acpi_hpet_test(struct acpi_hpet_softc *sc); 58 59 static char *hpet_ids[] = { "PNP0103", NULL }; 60 61 #define HPET_MEM_WIDTH 0x400 /* Expected memory region size */ 62 #define HPET_OFFSET_INFO 0 /* Location of info in region */ 63 #define HPET_OFFSET_PERIOD 4 /* Location of period (1/hz) */ 64 #define HPET_OFFSET_ENABLE 0x10 /* Location of enable word */ 65 #define HPET_OFFSET_VALUE 0xf0 /* Location of actual timer value */ 66 67 #define DEV_HPET(x) (acpi_get_magic(x) == (uintptr_t)&acpi_hpet_devclass) 68 69 struct timecounter hpet_timecounter = { 70 .tc_get_timecount = hpet_get_timecount, 71 .tc_counter_mask = ~0u, 72 .tc_name = "HPET", 73 .tc_quality = 900, 74 }; 75 76 static u_int 77 hpet_get_timecount(struct timecounter *tc) 78 { 79 struct acpi_hpet_softc *sc; 80 81 sc = tc->tc_priv; 82 return (bus_read_4(sc->mem_res, HPET_OFFSET_VALUE)); 83 } 84 85 static void 86 hpet_enable(struct acpi_hpet_softc *sc) 87 { 88 uint32_t val; 89 90 val = bus_read_4(sc->mem_res, HPET_OFFSET_ENABLE); 91 bus_write_4(sc->mem_res, HPET_OFFSET_ENABLE, val | 1); 92 } 93 94 static void 95 hpet_disable(struct acpi_hpet_softc *sc) 96 { 97 uint32_t val; 98 99 val = bus_read_4(sc->mem_res, HPET_OFFSET_ENABLE); 100 bus_write_4(sc->mem_res, HPET_OFFSET_ENABLE, val & ~1); 101 } 102 103 /* Discover the HPET via the ACPI table of the same name. */ 104 static void 105 acpi_hpet_identify(driver_t *driver, device_t parent) 106 { 107 ACPI_TABLE_HPET *hpet; 108 ACPI_TABLE_HEADER *hdr; 109 ACPI_STATUS status; 110 device_t child; 111 112 /* Only one HPET device can be added. */ 113 if (devclass_get_device(acpi_hpet_devclass, 0)) 114 return; 115 116 /* Currently, ID and minimum clock tick info is unused. */ 117 118 status = AcpiGetTable(ACPI_SIG_HPET, 1, (ACPI_TABLE_HEADER **)&hdr); 119 if (ACPI_FAILURE(status)) 120 return; 121 122 /* 123 * The unit number could be derived from hdr->Sequence but we only 124 * support one HPET device. 125 */ 126 hpet = (ACPI_TABLE_HPET *)hdr; 127 if (hpet->Sequence != 0) 128 printf("ACPI HPET table warning: Sequence is non-zero (%d)\n", 129 hpet->Sequence); 130 child = BUS_ADD_CHILD(parent, ACPI_DEV_BASE_ORDER, "acpi_hpet", 0); 131 if (child == NULL) { 132 printf("%s: can't add child\n", __func__); 133 return; 134 } 135 136 /* Record a magic value so we can detect this device later. */ 137 acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass); 138 bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address, 139 HPET_MEM_WIDTH); 140 } 141 142 static int 143 acpi_hpet_probe(device_t dev) 144 { 145 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 146 147 if (acpi_disabled("hpet")) 148 return (ENXIO); 149 if (!DEV_HPET(dev) && 150 (ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL || 151 device_get_unit(dev) != 0)) 152 return (ENXIO); 153 154 device_set_desc(dev, "High Precision Event Timer"); 155 return (0); 156 } 157 158 static int 159 acpi_hpet_attach(device_t dev) 160 { 161 struct acpi_hpet_softc *sc; 162 int rid; 163 uint32_t val, val2; 164 uintmax_t freq; 165 166 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 167 168 sc = device_get_softc(dev); 169 sc->dev = dev; 170 sc->handle = acpi_get_handle(dev); 171 172 rid = 0; 173 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 174 RF_ACTIVE); 175 if (sc->mem_res == NULL) 176 return (ENOMEM); 177 178 /* Validate that we can access the whole region. */ 179 if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) { 180 device_printf(dev, "memory region width %ld too small\n", 181 rman_get_size(sc->mem_res)); 182 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res); 183 return (ENXIO); 184 } 185 186 /* Be sure timer is enabled. */ 187 hpet_enable(sc); 188 189 /* Read basic statistics about the timer. */ 190 val = bus_read_4(sc->mem_res, HPET_OFFSET_PERIOD); 191 if (val == 0) { 192 device_printf(dev, "invalid period\n"); 193 hpet_disable(sc); 194 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res); 195 return (ENXIO); 196 } 197 198 freq = (1000000000000000LL + val / 2) / val; 199 if (bootverbose) { 200 val = bus_read_4(sc->mem_res, HPET_OFFSET_INFO); 201 device_printf(dev, 202 "vend: 0x%x rev: 0x%x num: %d hz: %jd opts:%s%s\n", 203 val >> 16, val & 0xff, (val >> 18) & 0xf, freq, 204 ((val >> 15) & 1) ? " leg_route" : "", 205 ((val >> 13) & 1) ? " count_size" : ""); 206 } 207 208 if (testenv("debug.acpi.hpet_test")) 209 acpi_hpet_test(sc); 210 211 /* 212 * Don't attach if the timer never increments. Since the spec 213 * requires it to be at least 10 MHz, it has to change in 1 us. 214 */ 215 val = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 216 DELAY(1); 217 val2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 218 if (val == val2) { 219 device_printf(dev, "HPET never increments, disabling\n"); 220 hpet_disable(sc); 221 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res); 222 return (ENXIO); 223 } 224 225 hpet_timecounter.tc_frequency = freq; 226 hpet_timecounter.tc_priv = sc; 227 tc_init(&hpet_timecounter); 228 229 return (0); 230 } 231 232 static int 233 acpi_hpet_detach(device_t dev) 234 { 235 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 236 237 /* XXX Without a tc_remove() function, we can't detach. */ 238 return (EBUSY); 239 } 240 241 static int 242 acpi_hpet_suspend(device_t dev) 243 { 244 struct acpi_hpet_softc *sc; 245 246 /* 247 * Disable the timer during suspend. The timer will not lose 248 * its state in S1 or S2, but we are required to disable 249 * it. 250 */ 251 sc = device_get_softc(dev); 252 hpet_disable(sc); 253 254 return (0); 255 } 256 257 static int 258 acpi_hpet_resume(device_t dev) 259 { 260 struct acpi_hpet_softc *sc; 261 262 /* Re-enable the timer after a resume to keep the clock advancing. */ 263 sc = device_get_softc(dev); 264 hpet_enable(sc); 265 266 return (0); 267 } 268 269 /* Print some basic latency/rate information to assist in debugging. */ 270 static void 271 acpi_hpet_test(struct acpi_hpet_softc *sc) 272 { 273 int i; 274 uint32_t u1, u2; 275 struct bintime b0, b1, b2; 276 struct timespec ts; 277 278 binuptime(&b0); 279 binuptime(&b0); 280 binuptime(&b1); 281 u1 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 282 for (i = 1; i < 1000; i++) 283 u2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 284 binuptime(&b2); 285 u2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 286 287 bintime_sub(&b2, &b1); 288 bintime_sub(&b1, &b0); 289 bintime_sub(&b2, &b1); 290 bintime2timespec(&b2, &ts); 291 292 device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n", 293 (long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1); 294 295 device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000); 296 } 297 298 static device_method_t acpi_hpet_methods[] = { 299 /* Device interface */ 300 DEVMETHOD(device_identify, acpi_hpet_identify), 301 DEVMETHOD(device_probe, acpi_hpet_probe), 302 DEVMETHOD(device_attach, acpi_hpet_attach), 303 DEVMETHOD(device_detach, acpi_hpet_detach), 304 DEVMETHOD(device_suspend, acpi_hpet_suspend), 305 DEVMETHOD(device_resume, acpi_hpet_resume), 306 307 {0, 0} 308 }; 309 310 static driver_t acpi_hpet_driver = { 311 "acpi_hpet", 312 acpi_hpet_methods, 313 sizeof(struct acpi_hpet_softc), 314 }; 315 316 317 DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, 0, 0); 318 MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1); 319