smist.c revision 182401
1/*- 2 * Copyright (c) 2005 Bruno Ducrot 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25/* 26 * This driver is based upon information found by examining speedstep-0.5 27 * from Marc Lehman, which includes all the reverse engineering effort of 28 * Malik Martin (function 1 and 2 of the GSI). 29 * 30 * The correct way for the OS to take ownership from the BIOS was found by 31 * Hiroshi Miura (function 0 of the GSI). 32 * 33 * Finally, the int 15h call interface was (partially) documented by Intel. 34 * 35 * Many thanks to Jon Noack for testing and debugging this driver. 36 */ 37 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: head/sys/i386/cpufreq/smist.c 182401 2008-08-28 19:55:18Z jhb $"); 40 41#include <sys/param.h> 42#include <sys/bus.h> 43#include <sys/cpu.h> 44#include <sys/kernel.h> 45#include <sys/module.h> 46#include <sys/systm.h> 47 48#include <machine/bus.h> 49#include <machine/md_var.h> 50#include <machine/vm86.h> 51 52#include <dev/pci/pcivar.h> 53#include <dev/pci/pcireg.h> 54 55#include <vm/vm.h> 56#include <vm/pmap.h> 57 58#include "cpufreq_if.h" 59 60#if 0 61#define DPRINT(dev, x...) device_printf(dev, x) 62#else 63#define DPRINT(dev, x...) 64#endif 65 66struct smist_softc { 67 device_t dev; 68 int smi_cmd; 69 int smi_data; 70 int command; 71 int flags; 72 struct cf_setting sets[2]; /* Only two settings. */ 73}; 74 75static char smist_magic[] = "Copyright (c) 1999 Intel Corporation"; 76 77static void smist_identify(driver_t *driver, device_t parent); 78static int smist_probe(device_t dev); 79static int smist_attach(device_t dev); 80static int smist_detach(device_t dev); 81static int smist_settings(device_t dev, struct cf_setting *sets, 82 int *count); 83static int smist_set(device_t dev, const struct cf_setting *set); 84static int smist_get(device_t dev, struct cf_setting *set); 85static int smist_type(device_t dev, int *type); 86 87static device_method_t smist_methods[] = { 88 /* Device interface */ 89 DEVMETHOD(device_identify, smist_identify), 90 DEVMETHOD(device_probe, smist_probe), 91 DEVMETHOD(device_attach, smist_attach), 92 DEVMETHOD(device_detach, smist_detach), 93 94 /* cpufreq interface */ 95 DEVMETHOD(cpufreq_drv_set, smist_set), 96 DEVMETHOD(cpufreq_drv_get, smist_get), 97 DEVMETHOD(cpufreq_drv_type, smist_type), 98 DEVMETHOD(cpufreq_drv_settings, smist_settings), 99 100 {0, 0} 101}; 102 103static driver_t smist_driver = { 104 "smist", smist_methods, sizeof(struct smist_softc) 105}; 106static devclass_t smist_devclass; 107DRIVER_MODULE(smist, cpu, smist_driver, smist_devclass, 0, 0); 108 109struct piix4_pci_device { 110 uint16_t vendor; 111 uint16_t device; 112 char *desc; 113}; 114 115static struct piix4_pci_device piix4_pci_devices[] = { 116 {0x8086, 0x7113, "Intel PIIX4 ISA bridge"}, 117 {0x8086, 0x719b, "Intel PIIX4 ISA bridge (embedded in MX440 chipset)"}, 118 119 {0, 0, NULL}, 120}; 121 122#define SET_OWNERSHIP 0 123#define GET_STATE 1 124#define SET_STATE 2 125 126static int 127int15_gsic_call(int *sig, int *smi_cmd, int *command, int *smi_data, int *flags) 128{ 129 struct vm86frame vmf; 130 131 bzero(&vmf, sizeof(vmf)); 132 vmf.vmf_eax = 0x0000E980; /* IST support */ 133 vmf.vmf_edx = 0x47534943; /* 'GSIC' in ASCII */ 134 vm86_intcall(0x15, &vmf); 135 136 if (vmf.vmf_eax == 0x47534943) { 137 *sig = vmf.vmf_eax; 138 *smi_cmd = vmf.vmf_ebx & 0xff; 139 *command = (vmf.vmf_ebx >> 16) & 0xff; 140 *smi_data = vmf.vmf_ecx; 141 *flags = vmf.vmf_edx; 142 } else { 143 *sig = -1; 144 *smi_cmd = -1; 145 *command = -1; 146 *smi_data = -1; 147 *flags = -1; 148 } 149 150 return (0); 151} 152 153/* Temporary structure to hold mapped page and status. */ 154struct set_ownership_data { 155 int smi_cmd; 156 int command; 157 int result; 158 void *buf; 159}; 160 161/* Perform actual SMI call to enable SpeedStep. */ 162static void 163set_ownership_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error) 164{ 165 struct set_ownership_data *data; 166 167 data = arg; 168 if (error) { 169 data->result = error; 170 return; 171 } 172 173 /* Copy in the magic string and send it by writing to the SMI port. */ 174 strlcpy(data->buf, smist_magic, PAGE_SIZE); 175 __asm __volatile( 176 "movl $-1, %%edi\n\t" 177 "out %%al, (%%dx)\n" 178 : "=D" (data->result) 179 : "a" (data->command), 180 "b" (0), 181 "c" (0), 182 "d" (data->smi_cmd), 183 "S" ((uint32_t)segs[0].ds_addr) 184 ); 185} 186 187static int 188set_ownership(device_t dev) 189{ 190 struct smist_softc *sc; 191 struct set_ownership_data cb_data; 192 bus_dma_tag_t tag; 193 bus_dmamap_t map; 194 195 /* 196 * Specify the region to store the magic string. Since its address is 197 * passed to the BIOS in a 32-bit register, we have to make sure it is 198 * located in a physical page below 4 GB (i.e., for PAE.) 199 */ 200 sc = device_get_softc(dev); 201 if (bus_dma_tag_create(/*parent*/ NULL, 202 /*alignment*/ PAGE_SIZE, /*no boundary*/ 0, 203 /*lowaddr*/ BUS_SPACE_MAXADDR_32BIT, /*highaddr*/ BUS_SPACE_MAXADDR, 204 NULL, NULL, /*maxsize*/ PAGE_SIZE, /*segments*/ 1, 205 /*maxsegsize*/ PAGE_SIZE, 0, busdma_lock_mutex, &Giant, 206 &tag) != 0) { 207 device_printf(dev, "can't create mem tag\n"); 208 return (ENXIO); 209 } 210 if (bus_dmamem_alloc(tag, &cb_data.buf, BUS_DMA_NOWAIT, &map) != 0) { 211 bus_dma_tag_destroy(tag); 212 device_printf(dev, "can't alloc mapped mem\n"); 213 return (ENXIO); 214 } 215 216 /* Load the physical page map and take ownership in the callback. */ 217 cb_data.smi_cmd = sc->smi_cmd; 218 cb_data.command = sc->command; 219 if (bus_dmamap_load(tag, map, cb_data.buf, PAGE_SIZE, set_ownership_cb, 220 &cb_data, BUS_DMA_NOWAIT) != 0) { 221 bus_dmamem_free(tag, cb_data.buf, map); 222 bus_dma_tag_destroy(tag); 223 device_printf(dev, "can't load mem\n"); 224 return (ENXIO); 225 }; 226 DPRINT(dev, "taking ownership over BIOS return %d\n", cb_data.result); 227 bus_dmamap_unload(tag, map); 228 bus_dmamem_free(tag, cb_data.buf, map); 229 bus_dma_tag_destroy(tag); 230 return (cb_data.result ? ENXIO : 0); 231} 232 233static int 234getset_state(struct smist_softc *sc, int *state, int function) 235{ 236 int new_state; 237 int result; 238 int eax; 239 240 if (!sc) 241 return (ENXIO); 242 243 if (function != GET_STATE && function != SET_STATE) 244 return (EINVAL); 245 246 DPRINT(sc->dev, "calling GSI\n"); 247 248 __asm __volatile( 249 "movl $-1, %%edi\n\t" 250 "out %%al, (%%dx)\n" 251 : "=a" (eax), 252 "=b" (new_state), 253 "=D" (result) 254 : "a" (sc->command), 255 "b" (function), 256 "c" (*state), 257 "d" (sc->smi_cmd) 258 ); 259 260 DPRINT(sc->dev, "GSI returned: eax %.8x ebx %.8x edi %.8x\n", 261 eax, new_state, result); 262 263 *state = new_state & 1; 264 265 switch (function) { 266 case GET_STATE: 267 if (eax) 268 return (ENXIO); 269 break; 270 case SET_STATE: 271 if (result) 272 return (ENXIO); 273 break; 274 } 275 return (0); 276} 277 278static void 279smist_identify(driver_t *driver, device_t parent) 280{ 281 struct piix4_pci_device *id; 282 device_t piix4 = NULL; 283 284 if (resource_disabled("ichst", 0)) 285 return; 286 287 /* Check for a supported processor */ 288 if (strcmp(cpu_vendor, "GenuineIntel") != 0) 289 return; 290 switch (cpu_id & 0xff0) { 291 case 0x680: /* Pentium III [coppermine] */ 292 case 0x6a0: /* Pentium III [Tualatin] */ 293 break; 294 default: 295 return; 296 } 297 298 /* Check for a supported PCI-ISA bridge */ 299 for (id = piix4_pci_devices; id->desc != NULL; ++id) { 300 if ((piix4 = pci_find_device(id->vendor, id->device)) != NULL) 301 break; 302 } 303 if (!piix4) 304 return; 305 306 if (bootverbose) 307 printf("smist: found supported isa bridge %s\n", id->desc); 308 309 if (device_find_child(parent, "smist", -1) != NULL) 310 return; 311 if (BUS_ADD_CHILD(parent, 30, "smist", -1) == NULL) 312 device_printf(parent, "smist: add child failed\n"); 313} 314 315static int 316smist_probe(device_t dev) 317{ 318 struct smist_softc *sc; 319 device_t ichss_dev, perf_dev; 320 int sig, smi_cmd, command, smi_data, flags; 321 int type; 322 int rv; 323 324 if (resource_disabled("smist", 0)) 325 return (ENXIO); 326 327 sc = device_get_softc(dev); 328 329 /* 330 * If the ACPI perf or ICH SpeedStep drivers have attached and not 331 * just offering info, let them manage things. 332 */ 333 perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1); 334 if (perf_dev && device_is_attached(perf_dev)) { 335 rv = CPUFREQ_DRV_TYPE(perf_dev, &type); 336 if (rv == 0 && (type & CPUFREQ_FLAG_INFO_ONLY) == 0) 337 return (ENXIO); 338 } 339 ichss_dev = device_find_child(device_get_parent(dev), "ichss", -1); 340 if (ichss_dev && device_is_attached(ichss_dev)) 341 return (ENXIO); 342 343 int15_gsic_call(&sig, &smi_cmd, &command, &smi_data, &flags); 344 if (bootverbose) 345 device_printf(dev, "sig %.8x smi_cmd %.4x command %.2x " 346 "smi_data %.4x flags %.8x\n", 347 sig, smi_cmd, command, smi_data, flags); 348 349 if (sig != -1) { 350 sc->smi_cmd = smi_cmd; 351 sc->smi_data = smi_data; 352 353 /* 354 * Sometimes int 15h 'GSIC' returns 0x80 for command, when 355 * it is actually 0x82. The Windows driver will overwrite 356 * this value given by the registry. 357 */ 358 if (command == 0x80) { 359 device_printf(dev, 360 "GSIC returned cmd 0x80, should be 0x82\n"); 361 command = 0x82; 362 } 363 sc->command = (sig & 0xffffff00) | (command & 0xff); 364 sc->flags = flags; 365 } else { 366 /* Give some default values */ 367 sc->smi_cmd = 0xb2; 368 sc->smi_data = 0xb3; 369 sc->command = 0x47534982; 370 sc->flags = 0; 371 } 372 373 device_set_desc(dev, "SpeedStep SMI"); 374 375 return (-1500); 376} 377 378static int 379smist_attach(device_t dev) 380{ 381 struct smist_softc *sc; 382 383 sc = device_get_softc(dev); 384 sc->dev = dev; 385 386 /* If we can't take ownership over BIOS, then bail out */ 387 if (set_ownership(dev) != 0) 388 return (ENXIO); 389 390 /* Setup some defaults for our exported settings. */ 391 sc->sets[0].freq = CPUFREQ_VAL_UNKNOWN; 392 sc->sets[0].volts = CPUFREQ_VAL_UNKNOWN; 393 sc->sets[0].power = CPUFREQ_VAL_UNKNOWN; 394 sc->sets[0].lat = 1000; 395 sc->sets[0].dev = dev; 396 sc->sets[1] = sc->sets[0]; 397 398 cpufreq_register(dev); 399 400 return (0); 401} 402 403static int 404smist_detach(device_t dev) 405{ 406 407 return (cpufreq_unregister(dev)); 408} 409 410static int 411smist_settings(device_t dev, struct cf_setting *sets, int *count) 412{ 413 struct smist_softc *sc; 414 struct cf_setting set; 415 int first, i; 416 417 if (sets == NULL || count == NULL) 418 return (EINVAL); 419 if (*count < 2) { 420 *count = 2; 421 return (E2BIG); 422 } 423 sc = device_get_softc(dev); 424 425 /* 426 * Estimate frequencies for both levels, temporarily switching to 427 * the other one if we haven't calibrated it yet. 428 */ 429 for (i = 0; i < 2; i++) { 430 if (sc->sets[i].freq == CPUFREQ_VAL_UNKNOWN) { 431 first = (i == 0) ? 1 : 0; 432 smist_set(dev, &sc->sets[i]); 433 smist_get(dev, &set); 434 smist_set(dev, &sc->sets[first]); 435 } 436 } 437 438 bcopy(sc->sets, sets, sizeof(sc->sets)); 439 *count = 2; 440 441 return (0); 442} 443 444static int 445smist_set(device_t dev, const struct cf_setting *set) 446{ 447 struct smist_softc *sc; 448 int rv, state, req_state, try; 449 450 /* Look up appropriate bit value based on frequency. */ 451 sc = device_get_softc(dev); 452 if (CPUFREQ_CMP(set->freq, sc->sets[0].freq)) 453 req_state = 0; 454 else if (CPUFREQ_CMP(set->freq, sc->sets[1].freq)) 455 req_state = 1; 456 else 457 return (EINVAL); 458 459 DPRINT(dev, "requested setting %d\n", req_state); 460 461 rv = getset_state(sc, &state, GET_STATE); 462 if (state == req_state) 463 return (0); 464 465 try = 3; 466 do { 467 rv = getset_state(sc, &req_state, SET_STATE); 468 469 /* Sleep for 200 microseconds. This value is just a guess. */ 470 if (rv) 471 DELAY(200); 472 } while (rv && --try); 473 DPRINT(dev, "set_state return %d, tried %d times\n", 474 rv, 4 - try); 475 476 return (rv); 477} 478 479static int 480smist_get(device_t dev, struct cf_setting *set) 481{ 482 struct smist_softc *sc; 483 uint64_t rate; 484 int state; 485 int rv; 486 487 sc = device_get_softc(dev); 488 rv = getset_state(sc, &state, GET_STATE); 489 if (rv != 0) 490 return (rv); 491 492 /* If we haven't changed settings yet, estimate the current value. */ 493 if (sc->sets[state].freq == CPUFREQ_VAL_UNKNOWN) { 494 cpu_est_clockrate(0, &rate); 495 sc->sets[state].freq = rate / 1000000; 496 DPRINT(dev, "get calibrated new rate of %d\n", 497 sc->sets[state].freq); 498 } 499 *set = sc->sets[state]; 500 501 return (0); 502} 503 504static int 505smist_type(device_t dev, int *type) 506{ 507 508 if (type == NULL) 509 return (EINVAL); 510 511 *type = CPUFREQ_TYPE_ABSOLUTE; 512 return (0); 513} 514