1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2007, 2008 Rui Paulo <rpaulo@FreeBSD.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 25 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * Device driver for Intel's On Die thermal sensor via MSR. 31 * First introduced in Intel's Core line of processors. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/bus.h> 39 #include <sys/conf.h> 40 #include <sys/kernel.h> 41 #include <sys/lock.h> 42 #include <sys/module.h> 43 #include <sys/mutex.h> 44 #include <sys/proc.h> /* for curthread */ 45 #include <sys/smp.h> 46 #include <sys/sysctl.h> 47 #include <sys/systm.h> 48 49 #include <machine/specialreg.h> 50 #include <machine/cpufunc.h> 51 #include <machine/cputypes.h> 52 #include <machine/md_var.h> 53 54 #define TZ_ZEROC 2731 55 56 #define THERM_STATUS_LOG 0x02 57 #define THERM_STATUS 0x01 58 #define THERM_STATUS_TEMP_SHIFT 16 59 #define THERM_STATUS_TEMP_MASK 0x7f 60 #define THERM_STATUS_RES_SHIFT 27 61 #define THERM_STATUS_RES_MASK 0x0f 62 #define THERM_STATUS_VALID_SHIFT 31 63 #define THERM_STATUS_VALID_MASK 0x01 64 65 struct coretemp_softc { 66 device_t sc_dev; 67 int sc_tjmax; 68 unsigned int sc_throttle_log; 69 }; 70 71 /* 72 * Device methods. 73 */ 74 static void coretemp_identify(driver_t *driver, device_t parent); 75 static int coretemp_probe(device_t dev); 76 static int coretemp_attach(device_t dev); 77 static int coretemp_detach(device_t dev); 78 79 static uint64_t coretemp_get_thermal_msr(int cpu); 80 static void coretemp_clear_thermal_msr(int cpu); 81 static int coretemp_get_val_sysctl(SYSCTL_HANDLER_ARGS); 82 static int coretemp_throttle_log_sysctl(SYSCTL_HANDLER_ARGS); 83 84 static device_method_t coretemp_methods[] = { 85 /* Device interface */ 86 DEVMETHOD(device_identify, coretemp_identify), 87 DEVMETHOD(device_probe, coretemp_probe), 88 DEVMETHOD(device_attach, coretemp_attach), 89 DEVMETHOD(device_detach, coretemp_detach), 90 91 DEVMETHOD_END 92 }; 93 94 static driver_t coretemp_driver = { 95 "coretemp", 96 coretemp_methods, 97 sizeof(struct coretemp_softc), 98 }; 99 100 enum therm_info { 101 CORETEMP_TEMP, 102 CORETEMP_DELTA, 103 CORETEMP_RESOLUTION, 104 CORETEMP_TJMAX, 105 }; 106 107 DRIVER_MODULE(coretemp, cpu, coretemp_driver, NULL, NULL); 108 109 static void 110 coretemp_identify(driver_t *driver, device_t parent) 111 { 112 device_t child; 113 u_int regs[4]; 114 115 /* Make sure we're not being doubly invoked. */ 116 if (device_find_child(parent, "coretemp", -1) != NULL) 117 return; 118 119 /* Check that CPUID 0x06 is supported and the vendor is Intel.*/ 120 if (cpu_high < 6 || cpu_vendor_id != CPU_VENDOR_INTEL) 121 return; 122 /* 123 * CPUID 0x06 returns 1 if the processor has on-die thermal 124 * sensors. EBX[0:3] contains the number of sensors. 125 */ 126 do_cpuid(0x06, regs); 127 if ((regs[0] & 0x1) != 1) 128 return; 129 130 /* 131 * We add a child for each CPU since settings must be performed 132 * on each CPU in the SMP case. 133 */ 134 child = device_add_child(parent, "coretemp", device_get_unit(parent)); 135 if (child == NULL) 136 device_printf(parent, "add coretemp child failed\n"); 137 } 138 139 static int 140 coretemp_probe(device_t dev) 141 { 142 if (resource_disabled("coretemp", 0)) 143 return (ENXIO); 144 145 device_set_desc(dev, "CPU On-Die Thermal Sensors"); 146 147 if (!bootverbose && device_get_unit(dev) != 0) 148 device_quiet(dev); 149 150 return (BUS_PROBE_GENERIC); 151 } 152 153 static int 154 coretemp_attach(device_t dev) 155 { 156 struct coretemp_softc *sc = device_get_softc(dev); 157 device_t pdev; 158 uint64_t msr; 159 int cpu_model, cpu_stepping; 160 int ret, tjtarget; 161 struct sysctl_oid *oid; 162 struct sysctl_ctx_list *ctx; 163 164 sc->sc_dev = dev; 165 pdev = device_get_parent(dev); 166 cpu_model = CPUID_TO_MODEL(cpu_id); 167 cpu_stepping = CPUID_TO_STEPPING(cpu_id); 168 169 /* 170 * Some CPUs, namely the PIII, don't have thermal sensors, but 171 * report them when the CPUID check is performed in 172 * coretemp_identify(). This leads to a later GPF when the sensor 173 * is queried via a MSR, so we stop here. 174 */ 175 if (cpu_model < 0xe) 176 return (ENXIO); 177 178 #if 0 /* 179 * XXXrpaulo: I have this CPU model and when it returns from C3 180 * coretemp continues to function properly. 181 */ 182 183 /* 184 * Check for errata AE18. 185 * "Processor Digital Thermal Sensor (DTS) Readout stops 186 * updating upon returning from C3/C4 state." 187 * 188 * Adapted from the Linux coretemp driver. 189 */ 190 if (cpu_model == 0xe && cpu_stepping < 0xc) { 191 msr = rdmsr(MSR_BIOS_SIGN); 192 msr = msr >> 32; 193 if (msr < 0x39) { 194 device_printf(dev, "not supported (Intel errata " 195 "AE18), try updating your BIOS\n"); 196 return (ENXIO); 197 } 198 } 199 #endif 200 201 /* 202 * Use 100C as the initial value. 203 */ 204 sc->sc_tjmax = 100; 205 206 if ((cpu_model == 0xf && cpu_stepping >= 2) || cpu_model == 0xe) { 207 /* 208 * On some Core 2 CPUs, there's an undocumented MSR that 209 * can tell us if Tj(max) is 100 or 85. 210 * 211 * The if-clause for CPUs having the MSR_IA32_EXT_CONFIG was adapted 212 * from the Linux coretemp driver. 213 */ 214 msr = rdmsr(MSR_IA32_EXT_CONFIG); 215 if (msr & (1 << 30)) 216 sc->sc_tjmax = 85; 217 } else if (cpu_model == 0x17) { 218 switch (cpu_stepping) { 219 case 0x6: /* Mobile Core 2 Duo */ 220 sc->sc_tjmax = 105; 221 break; 222 default: /* Unknown stepping */ 223 break; 224 } 225 } else if (cpu_model == 0x1c) { 226 switch (cpu_stepping) { 227 case 0xa: /* 45nm Atom D400, N400 and D500 series */ 228 sc->sc_tjmax = 100; 229 break; 230 default: 231 sc->sc_tjmax = 90; 232 break; 233 } 234 } else { 235 /* 236 * Attempt to get Tj(max) from MSR IA32_TEMPERATURE_TARGET. 237 * 238 * This method is described in Intel white paper "CPU 239 * Monitoring With DTS/PECI". (#322683) 240 */ 241 ret = rdmsr_safe(MSR_IA32_TEMPERATURE_TARGET, &msr); 242 if (ret == 0) { 243 tjtarget = (msr >> 16) & 0xff; 244 245 /* 246 * On earlier generation of processors, the value 247 * obtained from IA32_TEMPERATURE_TARGET register is 248 * an offset that needs to be summed with a model 249 * specific base. It is however not clear what 250 * these numbers are, with the publicly available 251 * documents from Intel. 252 * 253 * For now, we consider [70, 110]C range, as 254 * described in #322683, as "reasonable" and accept 255 * these values whenever the MSR is available for 256 * read, regardless the CPU model. 257 */ 258 if (tjtarget >= 70 && tjtarget <= 110) 259 sc->sc_tjmax = tjtarget; 260 else 261 device_printf(dev, "Tj(target) value %d " 262 "does not seem right.\n", tjtarget); 263 } else 264 device_printf(dev, "Can not get Tj(target) " 265 "from your CPU, using 100C.\n"); 266 } 267 268 if (bootverbose) 269 device_printf(dev, "Setting TjMax=%d\n", sc->sc_tjmax); 270 271 ctx = device_get_sysctl_ctx(dev); 272 273 oid = SYSCTL_ADD_NODE(ctx, 274 SYSCTL_CHILDREN(device_get_sysctl_tree(pdev)), OID_AUTO, 275 "coretemp", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 276 "Per-CPU thermal information"); 277 278 /* 279 * Add the MIBs to dev.cpu.N and dev.cpu.N.coretemp. 280 */ 281 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(device_get_sysctl_tree(pdev)), 282 OID_AUTO, "temperature", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, 283 dev, CORETEMP_TEMP, coretemp_get_val_sysctl, "IK", 284 "Current temperature"); 285 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "delta", 286 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_DELTA, 287 coretemp_get_val_sysctl, "I", 288 "Delta between TCC activation and current temperature"); 289 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "resolution", 290 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_RESOLUTION, 291 coretemp_get_val_sysctl, "I", 292 "Resolution of CPU thermal sensor"); 293 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "tjmax", 294 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_TJMAX, 295 coretemp_get_val_sysctl, "IK", 296 "TCC activation temperature"); 297 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, 298 "throttle_log", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, dev, 0, 299 coretemp_throttle_log_sysctl, "I", 300 "Set to 1 if the thermal sensor has tripped"); 301 302 return (0); 303 } 304 305 static int 306 coretemp_detach(device_t dev) 307 { 308 return (0); 309 } 310 311 struct coretemp_args { 312 u_int msr; 313 uint64_t val; 314 }; 315 316 /* 317 * The digital temperature reading is located at bit 16 318 * of MSR_THERM_STATUS. 319 * 320 * There is a bit on that MSR that indicates whether the 321 * temperature is valid or not. 322 * 323 * The temperature is computed by subtracting the temperature 324 * reading by Tj(max). 325 */ 326 static uint64_t 327 coretemp_get_thermal_msr(int cpu) 328 { 329 uint64_t res; 330 331 x86_msr_op(MSR_THERM_STATUS, MSR_OP_RENDEZVOUS_ONE | MSR_OP_READ | 332 MSR_OP_CPUID(cpu), 0, &res); 333 return (res); 334 } 335 336 static void 337 coretemp_clear_thermal_msr(int cpu) 338 { 339 x86_msr_op(MSR_THERM_STATUS, MSR_OP_RENDEZVOUS_ONE | MSR_OP_WRITE | 340 MSR_OP_CPUID(cpu), 0, NULL); 341 } 342 343 static int 344 coretemp_get_val_sysctl(SYSCTL_HANDLER_ARGS) 345 { 346 device_t dev; 347 uint64_t msr; 348 int val, tmp; 349 struct coretemp_softc *sc; 350 enum therm_info type; 351 char stemp[16]; 352 353 dev = (device_t) arg1; 354 msr = coretemp_get_thermal_msr(device_get_unit(dev)); 355 sc = device_get_softc(dev); 356 type = arg2; 357 358 if (((msr >> THERM_STATUS_VALID_SHIFT) & THERM_STATUS_VALID_MASK) != 1) { 359 val = -1; 360 } else { 361 switch (type) { 362 case CORETEMP_TEMP: 363 tmp = (msr >> THERM_STATUS_TEMP_SHIFT) & 364 THERM_STATUS_TEMP_MASK; 365 val = (sc->sc_tjmax - tmp) * 10 + TZ_ZEROC; 366 break; 367 case CORETEMP_DELTA: 368 val = (msr >> THERM_STATUS_TEMP_SHIFT) & 369 THERM_STATUS_TEMP_MASK; 370 break; 371 case CORETEMP_RESOLUTION: 372 val = (msr >> THERM_STATUS_RES_SHIFT) & 373 THERM_STATUS_RES_MASK; 374 break; 375 case CORETEMP_TJMAX: 376 val = sc->sc_tjmax * 10 + TZ_ZEROC; 377 break; 378 } 379 } 380 381 if (msr & THERM_STATUS_LOG) { 382 coretemp_clear_thermal_msr(device_get_unit(dev)); 383 sc->sc_throttle_log = 1; 384 385 /* 386 * Check for Critical Temperature Status and Critical 387 * Temperature Log. It doesn't really matter if the 388 * current temperature is invalid because the "Critical 389 * Temperature Log" bit will tell us if the Critical 390 * Temperature has * been reached in past. It's not 391 * directly related to the current temperature. 392 * 393 * If we reach a critical level, allow devctl(4) 394 * to catch this and shutdown the system. 395 */ 396 if (msr & THERM_STATUS) { 397 tmp = (msr >> THERM_STATUS_TEMP_SHIFT) & 398 THERM_STATUS_TEMP_MASK; 399 tmp = (sc->sc_tjmax - tmp) * 10 + TZ_ZEROC; 400 device_printf(dev, "critical temperature detected, " 401 "suggest system shutdown\n"); 402 snprintf(stemp, sizeof(stemp), "%d", tmp); 403 devctl_notify("coretemp", "Thermal", stemp, 404 "notify=0xcc"); 405 } 406 } 407 408 return (sysctl_handle_int(oidp, &val, 0, req)); 409 } 410 411 static int 412 coretemp_throttle_log_sysctl(SYSCTL_HANDLER_ARGS) 413 { 414 device_t dev; 415 uint64_t msr; 416 int error, val; 417 struct coretemp_softc *sc; 418 419 dev = (device_t) arg1; 420 msr = coretemp_get_thermal_msr(device_get_unit(dev)); 421 sc = device_get_softc(dev); 422 423 if (msr & THERM_STATUS_LOG) { 424 coretemp_clear_thermal_msr(device_get_unit(dev)); 425 sc->sc_throttle_log = 1; 426 } 427 428 val = sc->sc_throttle_log; 429 430 error = sysctl_handle_int(oidp, &val, 0, req); 431 432 if (error || !req->newptr) 433 return (error); 434 else if (val != 0) 435 return (EINVAL); 436 437 coretemp_clear_thermal_msr(device_get_unit(dev)); 438 sc->sc_throttle_log = 0; 439 440 return (0); 441 } 442