cpuctl.c revision 358582
1/*- 2 * Copyright (c) 2006-2008 Stanislav Sedov <stas@FreeBSD.org> 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 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: stable/11/sys/dev/cpuctl/cpuctl.c 358582 2020-03-03 15:12:00Z kib $"); 30 31#include <sys/param.h> 32#include <sys/systm.h> 33#include <sys/conf.h> 34#include <sys/fcntl.h> 35#include <sys/ioccom.h> 36#include <sys/malloc.h> 37#include <sys/module.h> 38#include <sys/mutex.h> 39#include <sys/priv.h> 40#include <sys/proc.h> 41#include <sys/queue.h> 42#include <sys/sched.h> 43#include <sys/kernel.h> 44#include <sys/sysctl.h> 45#include <sys/uio.h> 46#include <sys/pcpu.h> 47#include <sys/smp.h> 48#include <sys/pmckern.h> 49#include <sys/cpuctl.h> 50 51#include <vm/vm.h> 52#include <vm/vm_param.h> 53#include <vm/pmap.h> 54 55#include <machine/cpufunc.h> 56#include <machine/md_var.h> 57#include <machine/specialreg.h> 58#include <x86/ucode.h> 59 60static d_open_t cpuctl_open; 61static d_ioctl_t cpuctl_ioctl; 62 63#define CPUCTL_VERSION 1 64 65#ifdef CPUCTL_DEBUG 66# define DPRINTF(format,...) printf(format, __VA_ARGS__); 67#else 68# define DPRINTF(...) 69#endif 70 71#define UCODE_SIZE_MAX (4 * 1024 * 1024) 72 73static int cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, 74 struct thread *td); 75static int cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, 76 struct thread *td); 77static int cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data, 78 struct thread *td); 79static int cpuctl_do_eval_cpu_features(int cpu, struct thread *td); 80static int cpuctl_do_update(int cpu, cpuctl_update_args_t *data, 81 struct thread *td); 82static int update_intel(int cpu, cpuctl_update_args_t *args, 83 struct thread *td); 84static int update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td); 85static int update_via(int cpu, cpuctl_update_args_t *args, 86 struct thread *td); 87 88static struct cdev **cpuctl_devs; 89static MALLOC_DEFINE(M_CPUCTL, "cpuctl", "CPUCTL buffer"); 90 91static struct cdevsw cpuctl_cdevsw = { 92 .d_version = D_VERSION, 93 .d_open = cpuctl_open, 94 .d_ioctl = cpuctl_ioctl, 95 .d_name = "cpuctl", 96}; 97 98/* 99 * This function checks if specified cpu enabled or not. 100 */ 101static int 102cpu_enabled(int cpu) 103{ 104 105 return (pmc_cpu_is_disabled(cpu) == 0); 106} 107 108/* 109 * Check if the current thread is bound to a specific cpu. 110 */ 111static int 112cpu_sched_is_bound(struct thread *td) 113{ 114 int ret; 115 116 thread_lock(td); 117 ret = sched_is_bound(td); 118 thread_unlock(td); 119 return (ret); 120} 121 122/* 123 * Switch to target cpu to run. 124 */ 125static void 126set_cpu(int cpu, struct thread *td) 127{ 128 129 KASSERT(cpu >= 0 && cpu <= mp_maxid && cpu_enabled(cpu), 130 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 131 thread_lock(td); 132 sched_bind(td, cpu); 133 thread_unlock(td); 134 KASSERT(td->td_oncpu == cpu, 135 ("[cpuctl,%d]: cannot bind to target cpu %d on cpu %d", __LINE__, 136 cpu, td->td_oncpu)); 137} 138 139static void 140restore_cpu(int oldcpu, int is_bound, struct thread *td) 141{ 142 143 KASSERT(oldcpu >= 0 && oldcpu <= mp_maxid && cpu_enabled(oldcpu), 144 ("[cpuctl,%d]: bad cpu number %d", __LINE__, oldcpu)); 145 thread_lock(td); 146 if (is_bound == 0) 147 sched_unbind(td); 148 else 149 sched_bind(td, oldcpu); 150 thread_unlock(td); 151} 152 153int 154cpuctl_ioctl(struct cdev *dev, u_long cmd, caddr_t data, 155 int flags, struct thread *td) 156{ 157 int cpu, ret; 158 159 cpu = dev2unit(dev); 160 if (cpu > mp_maxid || !cpu_enabled(cpu)) { 161 DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu); 162 return (ENXIO); 163 } 164 /* Require write flag for "write" requests. */ 165 if ((cmd == CPUCTL_MSRCBIT || cmd == CPUCTL_MSRSBIT || 166 cmd == CPUCTL_UPDATE || cmd == CPUCTL_WRMSR || 167 cmd == CPUCTL_EVAL_CPU_FEATURES) && 168 (flags & FWRITE) == 0) 169 return (EPERM); 170 switch (cmd) { 171 case CPUCTL_RDMSR: 172 ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td); 173 break; 174 case CPUCTL_MSRSBIT: 175 case CPUCTL_MSRCBIT: 176 case CPUCTL_WRMSR: 177 ret = priv_check(td, PRIV_CPUCTL_WRMSR); 178 if (ret != 0) 179 goto fail; 180 ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td); 181 break; 182 case CPUCTL_CPUID: 183 ret = cpuctl_do_cpuid(cpu, (cpuctl_cpuid_args_t *)data, td); 184 break; 185 case CPUCTL_UPDATE: 186 ret = priv_check(td, PRIV_CPUCTL_UPDATE); 187 if (ret != 0) 188 goto fail; 189 ret = cpuctl_do_update(cpu, (cpuctl_update_args_t *)data, td); 190 break; 191 case CPUCTL_CPUID_COUNT: 192 ret = cpuctl_do_cpuid_count(cpu, 193 (cpuctl_cpuid_count_args_t *)data, td); 194 break; 195 case CPUCTL_EVAL_CPU_FEATURES: 196 ret = cpuctl_do_eval_cpu_features(cpu, td); 197 break; 198 default: 199 ret = EINVAL; 200 break; 201 } 202fail: 203 return (ret); 204} 205 206/* 207 * Actually perform cpuid operation. 208 */ 209static int 210cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data, 211 struct thread *td) 212{ 213 int is_bound = 0; 214 int oldcpu; 215 216 KASSERT(cpu >= 0 && cpu <= mp_maxid, 217 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 218 219 /* Explicitly clear cpuid data to avoid returning stale info. */ 220 bzero(data->data, sizeof(data->data)); 221 DPRINTF("[cpuctl,%d]: retrieving cpuid lev %#0x type %#0x for %d cpu\n", 222 __LINE__, data->level, data->level_type, cpu); 223#ifdef __i386__ 224 if (cpu_id == 0) 225 return (ENODEV); 226#endif 227 oldcpu = td->td_oncpu; 228 is_bound = cpu_sched_is_bound(td); 229 set_cpu(cpu, td); 230 cpuid_count(data->level, data->level_type, data->data); 231 restore_cpu(oldcpu, is_bound, td); 232 return (0); 233} 234 235static int 236cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td) 237{ 238 cpuctl_cpuid_count_args_t cdata; 239 int error; 240 241 cdata.level = data->level; 242 /* Override the level type. */ 243 cdata.level_type = 0; 244 error = cpuctl_do_cpuid_count(cpu, &cdata, td); 245 bcopy(cdata.data, data->data, sizeof(data->data)); /* Ignore error */ 246 return (error); 247} 248 249/* 250 * Actually perform MSR operations. 251 */ 252static int 253cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td) 254{ 255 uint64_t reg; 256 int is_bound = 0; 257 int oldcpu; 258 int ret; 259 260 KASSERT(cpu >= 0 && cpu <= mp_maxid, 261 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 262 263 /* 264 * Explicitly clear cpuid data to avoid returning stale 265 * info 266 */ 267 DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__, 268 data->msr, cpu); 269#ifdef __i386__ 270 if ((cpu_feature & CPUID_MSR) == 0) 271 return (ENODEV); 272#endif 273 oldcpu = td->td_oncpu; 274 is_bound = cpu_sched_is_bound(td); 275 set_cpu(cpu, td); 276 if (cmd == CPUCTL_RDMSR) { 277 data->data = 0; 278 ret = rdmsr_safe(data->msr, &data->data); 279 } else if (cmd == CPUCTL_WRMSR) { 280 ret = wrmsr_safe(data->msr, data->data); 281 } else if (cmd == CPUCTL_MSRSBIT) { 282 critical_enter(); 283 ret = rdmsr_safe(data->msr, ®); 284 if (ret == 0) 285 ret = wrmsr_safe(data->msr, reg | data->data); 286 critical_exit(); 287 } else if (cmd == CPUCTL_MSRCBIT) { 288 critical_enter(); 289 ret = rdmsr_safe(data->msr, ®); 290 if (ret == 0) 291 ret = wrmsr_safe(data->msr, reg & ~data->data); 292 critical_exit(); 293 } else 294 panic("[cpuctl,%d]: unknown operation requested: %lu", 295 __LINE__, cmd); 296 restore_cpu(oldcpu, is_bound, td); 297 return (ret); 298} 299 300/* 301 * Actually perform microcode update. 302 */ 303static int 304cpuctl_do_update(int cpu, cpuctl_update_args_t *data, struct thread *td) 305{ 306 cpuctl_cpuid_args_t args = { 307 .level = 0, 308 }; 309 char vendor[13]; 310 int ret; 311 312 KASSERT(cpu >= 0 && cpu <= mp_maxid, 313 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 314 DPRINTF("[cpuctl,%d]: XXX %d", __LINE__, cpu); 315 316 ret = cpuctl_do_cpuid(cpu, &args, td); 317 if (ret != 0) 318 return (ret); 319 ((uint32_t *)vendor)[0] = args.data[1]; 320 ((uint32_t *)vendor)[1] = args.data[3]; 321 ((uint32_t *)vendor)[2] = args.data[2]; 322 vendor[12] = '\0'; 323 if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) == 0) 324 ret = update_intel(cpu, data, td); 325 else if(strncmp(vendor, AMD_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0) 326 ret = update_amd(cpu, data, td); 327 else if(strncmp(vendor, CENTAUR_VENDOR_ID, sizeof(CENTAUR_VENDOR_ID)) 328 == 0) 329 ret = update_via(cpu, data, td); 330 else 331 ret = ENXIO; 332 return (ret); 333} 334 335struct ucode_update_data { 336 void *ptr; 337 int cpu; 338 int ret; 339}; 340 341static void 342ucode_intel_load_rv(void *arg) 343{ 344 struct ucode_update_data *d; 345 346 d = arg; 347 if (PCPU_GET(cpuid) == d->cpu) 348 d->ret = ucode_intel_load(d->ptr, true, NULL, NULL); 349} 350 351static int 352update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td) 353{ 354 struct ucode_update_data d; 355 void *ptr; 356 int is_bound, oldcpu, ret; 357 358 if (args->size == 0 || args->data == NULL) { 359 DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__); 360 return (EINVAL); 361 } 362 if (args->size > UCODE_SIZE_MAX) { 363 DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__); 364 return (EINVAL); 365 } 366 367 /* 368 * 16 byte alignment required. Rely on the fact that 369 * malloc(9) always returns the pointer aligned at least on 370 * the size of the allocation. 371 */ 372 ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK); 373 if (copyin(args->data, ptr, args->size) != 0) { 374 DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed", 375 __LINE__, args->data, ptr, args->size); 376 ret = EFAULT; 377 goto out; 378 } 379 oldcpu = td->td_oncpu; 380 is_bound = cpu_sched_is_bound(td); 381 set_cpu(cpu, td); 382 d.ptr = ptr; 383 d.cpu = cpu; 384 smp_rendezvous(NULL, ucode_intel_load_rv, NULL, &d); 385 restore_cpu(oldcpu, is_bound, td); 386 ret = d.ret; 387 388 /* 389 * Replace any existing update. This ensures that the new update 390 * will be reloaded automatically during ACPI resume. 391 */ 392 if (ret == 0) 393 ptr = ucode_update(ptr); 394 395out: 396 free(ptr, M_CPUCTL); 397 return (ret); 398} 399 400/* 401 * NB: MSR 0xc0010020, MSR_K8_UCODE_UPDATE, is not documented by AMD. 402 * Coreboot, illumos and Linux source code was used to understand 403 * its workings. 404 */ 405static void 406amd_ucode_wrmsr(void *ucode_ptr) 407{ 408 uint32_t tmp[4]; 409 410 wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)ucode_ptr); 411 do_cpuid(0, tmp); 412} 413 414static int 415update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td) 416{ 417 void *ptr; 418 int ret; 419 420 if (args->size == 0 || args->data == NULL) { 421 DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__); 422 return (EINVAL); 423 } 424 if (args->size > UCODE_SIZE_MAX) { 425 DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__); 426 return (EINVAL); 427 } 428 429 /* 430 * 16 byte alignment required. Rely on the fact that 431 * malloc(9) always returns the pointer aligned at least on 432 * the size of the allocation. 433 */ 434 ptr = malloc(args->size + 16, M_CPUCTL, M_ZERO | M_WAITOK); 435 if (copyin(args->data, ptr, args->size) != 0) { 436 DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed", 437 __LINE__, args->data, ptr, args->size); 438 ret = EFAULT; 439 goto fail; 440 } 441 smp_rendezvous(NULL, amd_ucode_wrmsr, NULL, ptr); 442 ret = 0; 443fail: 444 free(ptr, M_CPUCTL); 445 return (ret); 446} 447 448static int 449update_via(int cpu, cpuctl_update_args_t *args, struct thread *td) 450{ 451 void *ptr; 452 uint64_t rev0, rev1, res; 453 uint32_t tmp[4]; 454 int is_bound; 455 int oldcpu; 456 int ret; 457 458 if (args->size == 0 || args->data == NULL) { 459 DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__); 460 return (EINVAL); 461 } 462 if (args->size > UCODE_SIZE_MAX) { 463 DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__); 464 return (EINVAL); 465 } 466 467 /* 468 * 4 byte alignment required. 469 */ 470 ptr = malloc(args->size, M_CPUCTL, M_WAITOK); 471 if (copyin(args->data, ptr, args->size) != 0) { 472 DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed", 473 __LINE__, args->data, ptr, args->size); 474 ret = EFAULT; 475 goto fail; 476 } 477 oldcpu = td->td_oncpu; 478 is_bound = cpu_sched_is_bound(td); 479 set_cpu(cpu, td); 480 critical_enter(); 481 rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current microcode revision. */ 482 483 /* 484 * Perform update. 485 */ 486 wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr)); 487 do_cpuid(1, tmp); 488 489 /* 490 * Result are in low byte of MSR FCR5: 491 * 0x00: No update has been attempted since RESET. 492 * 0x01: The last attempted update was successful. 493 * 0x02: The last attempted update was unsuccessful due to a bad 494 * environment. No update was loaded and any preexisting 495 * patches are still active. 496 * 0x03: The last attempted update was not applicable to this processor. 497 * No update was loaded and any preexisting patches are still 498 * active. 499 * 0x04: The last attempted update was not successful due to an invalid 500 * update data block. No update was loaded and any preexisting 501 * patches are still active 502 */ 503 rdmsr_safe(0x1205, &res); 504 res &= 0xff; 505 critical_exit(); 506 rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new microcode revision. */ 507 restore_cpu(oldcpu, is_bound, td); 508 509 DPRINTF("[cpu,%d]: rev0=%x rev1=%x res=%x\n", __LINE__, 510 (unsigned)(rev0 >> 32), (unsigned)(rev1 >> 32), (unsigned)res); 511 512 if (res != 0x01) 513 ret = EINVAL; 514 else 515 ret = 0; 516fail: 517 free(ptr, M_CPUCTL); 518 return (ret); 519} 520 521static int 522cpuctl_do_eval_cpu_features(int cpu, struct thread *td) 523{ 524 int is_bound = 0; 525 int oldcpu; 526 527 KASSERT(cpu >= 0 && cpu <= mp_maxid, 528 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 529 530#ifdef __i386__ 531 if (cpu_id == 0) 532 return (ENODEV); 533#endif 534 oldcpu = td->td_oncpu; 535 is_bound = cpu_sched_is_bound(td); 536 set_cpu(cpu, td); 537 identify_cpu1(); 538 identify_cpu2(); 539 restore_cpu(oldcpu, is_bound, td); 540 hw_ibrs_recalculate(true); 541 hw_ssb_recalculate(true); 542#ifdef __amd64__ 543 pmap_allow_2m_x_ept_recalculate(); 544#endif 545 hw_mds_recalculate(); 546 x86_taa_recalculate(); 547 printcpuinfo(); 548 return (0); 549} 550 551 552int 553cpuctl_open(struct cdev *dev, int flags, int fmt __unused, struct thread *td) 554{ 555 int ret = 0; 556 int cpu; 557 558 cpu = dev2unit(dev); 559 if (cpu > mp_maxid || !cpu_enabled(cpu)) { 560 DPRINTF("[cpuctl,%d]: incorrect cpu number %d\n", __LINE__, 561 cpu); 562 return (ENXIO); 563 } 564 if (flags & FWRITE) 565 ret = securelevel_gt(td->td_ucred, 0); 566 return (ret); 567} 568 569static int 570cpuctl_modevent(module_t mod __unused, int type, void *data __unused) 571{ 572 int cpu; 573 574 switch(type) { 575 case MOD_LOAD: 576 if (bootverbose) 577 printf("cpuctl: access to MSR registers/cpuid info.\n"); 578 cpuctl_devs = malloc(sizeof(*cpuctl_devs) * (mp_maxid + 1), M_CPUCTL, 579 M_WAITOK | M_ZERO); 580 CPU_FOREACH(cpu) 581 if (cpu_enabled(cpu)) 582 cpuctl_devs[cpu] = make_dev(&cpuctl_cdevsw, cpu, 583 UID_ROOT, GID_KMEM, 0640, "cpuctl%d", cpu); 584 break; 585 case MOD_UNLOAD: 586 CPU_FOREACH(cpu) { 587 if (cpuctl_devs[cpu] != NULL) 588 destroy_dev(cpuctl_devs[cpu]); 589 } 590 free(cpuctl_devs, M_CPUCTL); 591 break; 592 case MOD_SHUTDOWN: 593 break; 594 default: 595 return (EOPNOTSUPP); 596 } 597 return (0); 598} 599 600DEV_MODULE(cpuctl, cpuctl_modevent, NULL); 601MODULE_VERSION(cpuctl, CPUCTL_VERSION); 602