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 /* Discover the HPET via the ACPI table of the same name. */ 86 void 87 acpi_hpet_table_probe(device_t parent) 88 { 89 ACPI_TABLE_HPET *hpet; 90 ACPI_TABLE_HEADER *hdr; 91 ACPI_STATUS status; 92 device_t child; 93 94 /* Currently, ID and minimum clock tick info is unused. */ 95 96 status = AcpiGetTable(ACPI_SIG_HPET, 1, (ACPI_TABLE_HEADER **)&hdr); 97 if (ACPI_FAILURE(status)) 98 return; 99 100 /* 101 * The unit number could be derived from hdr->Sequence but we only 102 * support one HPET device. 103 */ 104 hpet = (ACPI_TABLE_HPET *)hdr; 105 if (hpet->Sequence != 0) 106 printf("ACPI HPET table warning: Sequence is non-zero (%d)\n", 107 hpet->Sequence); 108 child = BUS_ADD_CHILD(parent, 0, "acpi_hpet", 0); 109 if (child == NULL) { 110 printf("%s: can't add child\n", __func__); 111 return; 112 } 113 114 /* Record a magic value so we can detect this device later. */ 115 acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass); 116 bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address, 117 HPET_MEM_WIDTH); 118 if (device_probe_and_attach(child) != 0) 119 device_delete_child(parent, child); 120 } 121 122 static int 123 acpi_hpet_probe(device_t dev) 124 { 125 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 126 127 if (acpi_disabled("hpet")) 128 return (ENXIO); 129 if (!DEV_HPET(dev) && 130 (ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL || 131 device_get_unit(dev) != 0)) 132 return (ENXIO); 133 134 device_set_desc(dev, "High Precision Event Timer"); 135 return (0); 136 } 137 138 static int 139 acpi_hpet_attach(device_t dev) 140 { 141 struct acpi_hpet_softc *sc; 142 int rid; 143 uint32_t val, val2; 144 uintmax_t freq; 145 146 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 147 148 sc = device_get_softc(dev); 149 sc->dev = dev; 150 sc->handle = acpi_get_handle(dev); 151 152 rid = 0; 153 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 154 RF_ACTIVE); 155 if (sc->mem_res == NULL) 156 return (ENOMEM); 157 158 /* Validate that we can access the whole region. */ 159 if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) { 160 device_printf(dev, "memory region width %ld too small\n", 161 rman_get_size(sc->mem_res)); 162 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res); 163 return (ENXIO); 164 } 165 166 /* Be sure timer is enabled. */ 167 bus_write_4(sc->mem_res, HPET_OFFSET_ENABLE, 1); 168 169 /* Read basic statistics about the timer. */ 170 val = bus_read_4(sc->mem_res, HPET_OFFSET_PERIOD); 171 freq = (1000000000000000LL + val / 2) / val; 172 if (bootverbose) { 173 val = bus_read_4(sc->mem_res, HPET_OFFSET_INFO); 174 device_printf(dev, 175 "vend: 0x%x rev: 0x%x num: %d hz: %jd opts:%s%s\n", 176 val >> 16, val & 0xff, (val >> 18) & 0xf, freq, 177 ((val >> 15) & 1) ? " leg_route" : "", 178 ((val >> 13) & 1) ? " count_size" : ""); 179 } 180 181 if (testenv("debug.acpi.hpet_test")) 182 acpi_hpet_test(sc); 183 184 /* 185 * Don't attach if the timer never increments. Since the spec 186 * requires it to be at least 10 MHz, it has to change in 1 us. 187 */ 188 val = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 189 DELAY(1); 190 val2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 191 if (val == val2) { 192 device_printf(dev, "HPET never increments, disabling\n"); 193 bus_write_4(sc->mem_res, HPET_OFFSET_ENABLE, 0); 194 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res); 195 return (ENXIO); 196 } 197 198 hpet_timecounter.tc_frequency = freq; 199 hpet_timecounter.tc_priv = sc; 200 tc_init(&hpet_timecounter); 201 202 return (0); 203 } 204 205 static int 206 acpi_hpet_detach(device_t dev) 207 { 208 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 209 210 /* XXX Without a tc_remove() function, we can't detach. */ 211 return (EBUSY); 212 } 213 214 static int 215 acpi_hpet_resume(device_t dev) 216 { 217 struct acpi_hpet_softc *sc; 218 219 /* Re-enable the timer after a resume to keep the clock advancing. */ 220 sc = device_get_softc(dev); 221 bus_write_4(sc->mem_res, HPET_OFFSET_ENABLE, 1); 222 223 return (0); 224 } 225 226 /* Print some basic latency/rate information to assist in debugging. */ 227 static void 228 acpi_hpet_test(struct acpi_hpet_softc *sc) 229 { 230 int i; 231 uint32_t u1, u2; 232 struct bintime b0, b1, b2; 233 struct timespec ts; 234 235 binuptime(&b0); 236 binuptime(&b0); 237 binuptime(&b1); 238 u1 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 239 for (i = 1; i < 1000; i++) 240 u2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 241 binuptime(&b2); 242 u2 = bus_read_4(sc->mem_res, HPET_OFFSET_VALUE); 243 244 bintime_sub(&b2, &b1); 245 bintime_sub(&b1, &b0); 246 bintime_sub(&b2, &b1); 247 bintime2timespec(&b2, &ts); 248 249 device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n", 250 (long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1); 251 252 device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000); 253 } 254 255 static device_method_t acpi_hpet_methods[] = { 256 /* Device interface */ 257 DEVMETHOD(device_probe, acpi_hpet_probe), 258 DEVMETHOD(device_attach, acpi_hpet_attach), 259 DEVMETHOD(device_detach, acpi_hpet_detach), 260 DEVMETHOD(device_resume, acpi_hpet_resume), 261 262 {0, 0} 263 }; 264 265 static driver_t acpi_hpet_driver = { 266 "acpi_hpet", 267 acpi_hpet_methods, 268 sizeof(struct acpi_hpet_softc), 269 }; 270 271 272 DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, 0, 0); 273 MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1); 274