1 /*- 2 * Copyright (c) 2001 Michael Smith 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_cpu.c,v 1.16.4.1 2003/08/22 20:49:20 jhb Exp $ 27 * $DragonFly: src/sys/dev/acpica/Attic/acpi_cpu.c,v 1.1 2003/09/24 03:32:16 drhodus Exp $ 28 */ 29 30 #include "opt_acpi.h" 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/bus.h> 34 #include <sys/power.h> 35 36 #include <machine/bus_pio.h> 37 #include <machine/bus.h> 38 #include <machine/resource.h> 39 #include <sys/rman.h> 40 41 #include "acpi.h" 42 43 #include <dev/acpica/acpivar.h> 44 45 /* 46 * Support for ACPI Processor devices. 47 * 48 * Note that this only provides ACPI 1.0 support (with the exception of the 49 * PSTATE_CNT field). 2.0 support will involve implementing _PTC, _PCT, 50 * _PSS and _PPC. 51 */ 52 53 /* 54 * Hooks for the ACPI CA debugging infrastructure 55 */ 56 #define _COMPONENT ACPI_PROCESSOR 57 ACPI_MODULE_NAME("PROCESSOR") 58 59 struct acpi_cpu_softc { 60 device_t cpu_dev; 61 ACPI_HANDLE cpu_handle; 62 63 u_int32_t cpu_id; 64 65 /* CPU throttling control register */ 66 struct resource *cpu_p_blk; 67 #define CPU_GET_P_CNT(sc) (bus_space_read_4(rman_get_bustag((sc)->cpu_p_blk), \ 68 rman_get_bushandle((sc)->cpu_p_blk), \ 69 0)) 70 #define CPU_SET_P_CNT(sc, val) (bus_space_write_4(rman_get_bustag((sc)->cpu_p_blk), \ 71 rman_get_bushandle((sc)->cpu_p_blk), \ 72 0, (val))) 73 #define CPU_P_CNT_THT_EN (1<<4) 74 }; 75 76 /* 77 * Speeds are stored in counts, from 1 - CPU_MAX_SPEED, and 78 * reported to the user in tenths of a percent. 79 */ 80 static u_int32_t cpu_duty_offset; 81 static u_int32_t cpu_duty_width; 82 #define CPU_MAX_SPEED (1 << cpu_duty_width) 83 #define CPU_SPEED_PERCENT(x) ((1000 * (x)) / CPU_MAX_SPEED) 84 #define CPU_SPEED_PRINTABLE(x) (CPU_SPEED_PERCENT(x) / 10),(CPU_SPEED_PERCENT(x) % 10) 85 86 static u_int32_t cpu_smi_cmd; /* should be a generic way to do this */ 87 static u_int8_t cpu_pstate_cnt; 88 89 static u_int32_t cpu_current_state; 90 static u_int32_t cpu_performance_state; 91 static u_int32_t cpu_economy_state; 92 static u_int32_t cpu_max_state; 93 94 static device_t *cpu_devices; 95 static int cpu_ndevices; 96 97 static struct sysctl_ctx_list acpi_cpu_sysctl_ctx; 98 static struct sysctl_oid *acpi_cpu_sysctl_tree; 99 100 static int acpi_cpu_probe(device_t dev); 101 static int acpi_cpu_attach(device_t dev); 102 static void acpi_cpu_init_throttling(void *arg); 103 static void acpi_cpu_set_speed(u_int32_t speed); 104 static void acpi_cpu_power_profile(void *arg); 105 static int acpi_cpu_speed_sysctl(SYSCTL_HANDLER_ARGS); 106 107 static device_method_t acpi_cpu_methods[] = { 108 /* Device interface */ 109 DEVMETHOD(device_probe, acpi_cpu_probe), 110 DEVMETHOD(device_attach, acpi_cpu_attach), 111 112 {0, 0} 113 }; 114 115 static driver_t acpi_cpu_driver = { 116 "acpi_cpu", 117 acpi_cpu_methods, 118 sizeof(struct acpi_cpu_softc), 119 }; 120 121 static devclass_t acpi_cpu_devclass; 122 DRIVER_MODULE(acpi_cpu, acpi, acpi_cpu_driver, acpi_cpu_devclass, 0, 0); 123 124 static int 125 acpi_cpu_probe(device_t dev) 126 { 127 if (!acpi_disabled("cpu") && 128 (acpi_get_type(dev) == ACPI_TYPE_PROCESSOR)) { 129 device_set_desc(dev, "CPU"); /* XXX get more verbose description? */ 130 return(0); 131 } 132 return(ENXIO); 133 } 134 135 static int 136 acpi_cpu_attach(device_t dev) 137 { 138 struct acpi_cpu_softc *sc; 139 struct acpi_softc *acpi_sc; 140 ACPI_OBJECT processor; 141 ACPI_BUFFER buf; 142 ACPI_STATUS status; 143 u_int32_t p_blk; 144 u_int32_t p_blk_length; 145 u_int32_t duty_end; 146 int rid; 147 148 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 149 150 ACPI_ASSERTLOCK; 151 152 sc = device_get_softc(dev); 153 sc->cpu_dev = dev; 154 sc->cpu_handle = acpi_get_handle(dev); 155 156 /* 157 * Get global parameters from the FADT. 158 */ 159 if (device_get_unit(sc->cpu_dev) == 0) { 160 cpu_duty_offset = AcpiGbl_FADT->DutyOffset; 161 cpu_duty_width = AcpiGbl_FADT->DutyWidth; 162 cpu_smi_cmd = AcpiGbl_FADT->SmiCmd; 163 cpu_pstate_cnt = AcpiGbl_FADT->PstateCnt; 164 165 /* validate the offset/width */ 166 if (cpu_duty_width > 0) { 167 duty_end = cpu_duty_offset + cpu_duty_width - 1; 168 /* check that it fits */ 169 if (duty_end > 31) { 170 printf("acpi_cpu: CLK_VAL field overflows P_CNT register\n"); 171 cpu_duty_width = 0; 172 } 173 /* check for overlap with the THT_EN bit */ 174 if ((cpu_duty_offset <= 4) && (duty_end >= 4)) { 175 printf("acpi_cpu: CLK_VAL field overlaps THT_EN bit\n"); 176 cpu_duty_width = 0; 177 } 178 } 179 180 /* 181 * Start the throttling process once the probe phase completes, if we think that 182 * it's going to be useful. If the duty width value is zero, there are no significant 183 * bits in the register and thus no throttled states. 184 */ 185 if (cpu_duty_width > 0) { 186 AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cpu_init_throttling, NULL); 187 188 acpi_sc = acpi_device_get_parent_softc(dev); 189 sysctl_ctx_init(&acpi_cpu_sysctl_ctx); 190 acpi_cpu_sysctl_tree = SYSCTL_ADD_NODE(&acpi_cpu_sysctl_ctx, 191 SYSCTL_CHILDREN(acpi_sc->acpi_sysctl_tree), 192 OID_AUTO, "cpu", CTLFLAG_RD, 0, ""); 193 194 SYSCTL_ADD_INT(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), 195 OID_AUTO, "max_speed", CTLFLAG_RD, 196 &cpu_max_state, 0, "maximum CPU speed"); 197 SYSCTL_ADD_INT(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), 198 OID_AUTO, "current_speed", CTLFLAG_RD, 199 &cpu_current_state, 0, "current CPU speed"); 200 SYSCTL_ADD_PROC(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), 201 OID_AUTO, "performance_speed", CTLTYPE_INT | CTLFLAG_RW, 202 &cpu_performance_state, 0, acpi_cpu_speed_sysctl, "I", ""); 203 SYSCTL_ADD_PROC(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), 204 OID_AUTO, "economy_speed", CTLTYPE_INT | CTLFLAG_RW, 205 &cpu_economy_state, 0, acpi_cpu_speed_sysctl, "I", ""); 206 } 207 } 208 209 /* 210 * Get the processor object. 211 */ 212 buf.Pointer = &processor; 213 buf.Length = sizeof(processor); 214 if (ACPI_FAILURE(status = AcpiEvaluateObject(sc->cpu_handle, NULL, NULL, &buf))) { 215 device_printf(sc->cpu_dev, "couldn't get Processor object - %s\n", AcpiFormatException(status)); 216 return_VALUE(ENXIO); 217 } 218 if (processor.Type != ACPI_TYPE_PROCESSOR) { 219 device_printf(sc->cpu_dev, "Processor object has bad type %d\n", processor.Type); 220 return_VALUE(ENXIO); 221 } 222 sc->cpu_id = processor.Processor.ProcId; 223 224 /* 225 * If it looks like we support throttling, find this CPU's P_BLK. 226 * 227 * Note that some systems seem to duplicate the P_BLK pointer across 228 * multiple CPUs, so not getting the resource is not fatal. 229 * 230 * XXX should support _PTC here as well, once we work out how to parse it. 231 * 232 * XXX is it valid to assume that the P_BLK must be 6 bytes long? 233 */ 234 if (cpu_duty_width > 0) { 235 p_blk = processor.Processor.PblkAddress; 236 p_blk_length = processor.Processor.PblkLength; 237 238 /* allocate bus space if possible */ 239 if ((p_blk > 0) && (p_blk_length == 6)) { 240 rid = 0; 241 bus_set_resource(sc->cpu_dev, SYS_RES_IOPORT, rid, p_blk, p_blk_length); 242 sc->cpu_p_blk = bus_alloc_resource(sc->cpu_dev, SYS_RES_IOPORT, &rid, 0, ~0, 1, 243 RF_ACTIVE); 244 245 ACPI_DEBUG_PRINT((ACPI_DB_IO, "acpi_cpu%d: throttling with P_BLK at 0x%x/%d%s\n", 246 device_get_unit(sc->cpu_dev), p_blk, p_blk_length, 247 sc->cpu_p_blk ? "" : " (shadowed)")); 248 } 249 } 250 return_VALUE(0); 251 } 252 253 /* 254 * Call this *after* all CPUs have been attached. 255 * 256 * Takes the ACPI lock to avoid fighting anyone over the SMI command 257 * port. Could probably lock less code. 258 */ 259 static void 260 acpi_cpu_init_throttling(void *arg) 261 { 262 int cpu_temp_speed; 263 ACPI_LOCK_DECL; 264 265 ACPI_LOCK; 266 267 /* get set of CPU devices */ 268 devclass_get_devices(acpi_cpu_devclass, &cpu_devices, &cpu_ndevices); 269 270 /* initialise throttling states */ 271 cpu_max_state = CPU_MAX_SPEED; 272 cpu_performance_state = cpu_max_state; 273 cpu_economy_state = cpu_performance_state / 2; 274 if (cpu_economy_state == 0) /* 0 is 'reserved' */ 275 cpu_economy_state++; 276 if (TUNABLE_INT_FETCH("hw.acpi.cpu.performance_speed", 277 &cpu_temp_speed) && cpu_temp_speed > 0 && 278 cpu_temp_speed <= cpu_max_state) 279 cpu_performance_state = cpu_temp_speed; 280 if (TUNABLE_INT_FETCH("hw.acpi.cpu.economy_speed", 281 &cpu_temp_speed) && cpu_temp_speed > 0 && 282 cpu_temp_speed <= cpu_max_state) 283 cpu_economy_state = cpu_temp_speed; 284 285 /* register performance profile change handler */ 286 EVENTHANDLER_REGISTER(power_profile_change, acpi_cpu_power_profile, NULL, 0); 287 288 /* if ACPI 2.0+, signal platform that we are taking over throttling */ 289 if (cpu_pstate_cnt != 0) { 290 /* XXX should be a generic interface for this */ 291 AcpiOsWritePort(cpu_smi_cmd, cpu_pstate_cnt, 8); 292 } 293 294 ACPI_UNLOCK; 295 296 /* set initial speed */ 297 acpi_cpu_power_profile(NULL); 298 299 printf("acpi_cpu: throttling enabled, %d steps (100%% to %d.%d%%), " 300 "currently %d.%d%%\n", CPU_MAX_SPEED, CPU_SPEED_PRINTABLE(1), 301 CPU_SPEED_PRINTABLE(cpu_current_state)); 302 } 303 304 /* 305 * Set CPUs to the new state. 306 * 307 * Must be called with the ACPI lock held. 308 */ 309 static void 310 acpi_cpu_set_speed(u_int32_t speed) 311 { 312 struct acpi_cpu_softc *sc; 313 int i; 314 u_int32_t p_cnt, clk_val; 315 316 ACPI_ASSERTLOCK; 317 318 /* iterate over processors */ 319 for (i = 0; i < cpu_ndevices; i++) { 320 sc = device_get_softc(cpu_devices[i]); 321 if (sc->cpu_p_blk == NULL) 322 continue; 323 324 /* get the current P_CNT value and disable throttling */ 325 p_cnt = CPU_GET_P_CNT(sc); 326 p_cnt &= ~CPU_P_CNT_THT_EN; 327 CPU_SET_P_CNT(sc, p_cnt); 328 329 /* if we're at maximum speed, that's all */ 330 if (speed < CPU_MAX_SPEED) { 331 332 /* mask the old CLK_VAL off and or-in the new value */ 333 clk_val = CPU_MAX_SPEED << cpu_duty_offset; 334 p_cnt &= ~clk_val; 335 p_cnt |= (speed << cpu_duty_offset); 336 337 /* write the new P_CNT value and then enable throttling */ 338 CPU_SET_P_CNT(sc, p_cnt); 339 p_cnt |= CPU_P_CNT_THT_EN; 340 CPU_SET_P_CNT(sc, p_cnt); 341 } 342 ACPI_VPRINT(sc->cpu_dev, acpi_device_get_parent_softc(sc->cpu_dev), 343 "set speed to %d.%d%%\n", CPU_SPEED_PRINTABLE(speed)); 344 } 345 cpu_current_state = speed; 346 } 347 348 /* 349 * Power profile change hook. 350 * 351 * Uses the ACPI lock to avoid reentrancy. 352 */ 353 static void 354 acpi_cpu_power_profile(void *arg) 355 { 356 int state; 357 u_int32_t new; 358 ACPI_LOCK_DECL; 359 360 state = power_profile_get_state(); 361 if (state != POWER_PROFILE_PERFORMANCE && 362 state != POWER_PROFILE_ECONOMY) { 363 return; 364 } 365 366 ACPI_LOCK; 367 368 switch (state) { 369 case POWER_PROFILE_PERFORMANCE: 370 new = cpu_performance_state; 371 break; 372 case POWER_PROFILE_ECONOMY: 373 new = cpu_economy_state; 374 break; 375 default: 376 new = cpu_current_state; 377 break; 378 } 379 380 if (cpu_current_state != new) 381 acpi_cpu_set_speed(new); 382 383 ACPI_UNLOCK; 384 } 385 386 /* 387 * Handle changes in the performance/ecomony CPU settings. 388 * 389 * Does not need the ACPI lock (although setting *argp should 390 * probably be atomic). 391 */ 392 static int 393 acpi_cpu_speed_sysctl(SYSCTL_HANDLER_ARGS) 394 { 395 u_int32_t *argp; 396 u_int32_t arg; 397 int error; 398 399 argp = (u_int32_t *)oidp->oid_arg1; 400 arg = *argp; 401 error = sysctl_handle_int(oidp, &arg, 0, req); 402 403 /* error or no new value */ 404 if ((error != 0) || (req->newptr == NULL)) 405 return(error); 406 407 /* range check */ 408 if ((arg < 1) || (arg > cpu_max_state)) 409 return(EINVAL); 410 411 /* set new value and possibly switch */ 412 *argp = arg; 413 acpi_cpu_power_profile(NULL); 414 415 return(0); 416 } 417