cpuctl.c revision 195189
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: head/sys/dev/cpuctl/cpuctl.c 195189 2009-06-30 12:35:47Z stas $"); 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 <machine/cpufunc.h> 52#include <machine/md_var.h> 53#include <machine/specialreg.h> 54 55static d_open_t cpuctl_open; 56static d_ioctl_t cpuctl_ioctl; 57 58#define CPUCTL_VERSION 1 59 60#ifdef DEBUG 61# define DPRINTF(format,...) printf(format, __VA_ARGS__); 62#else 63# define DPRINTF(...) 64#endif 65 66#define UCODE_SIZE_MAX (10 * 1024) 67 68static int cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, 69 struct thread *td); 70static int cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, 71 struct thread *td); 72static int cpuctl_do_update(int cpu, cpuctl_update_args_t *data, 73 struct thread *td); 74static int update_intel(int cpu, cpuctl_update_args_t *args, 75 struct thread *td); 76static int update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td); 77 78static struct cdev **cpuctl_devs; 79static MALLOC_DEFINE(M_CPUCTL, "cpuctl", "CPUCTL buffer"); 80 81static struct cdevsw cpuctl_cdevsw = { 82 .d_version = D_VERSION, 83 .d_open = cpuctl_open, 84 .d_ioctl = cpuctl_ioctl, 85 .d_name = "cpuctl", 86}; 87 88/* 89 * This function checks if specified cpu enabled or not. 90 */ 91static int 92cpu_enabled(int cpu) 93{ 94 95 return (pmc_cpu_is_disabled(cpu) == 0); 96} 97 98/* 99 * Check if the current thread is bound to a specific cpu. 100 */ 101static int 102cpu_sched_is_bound(struct thread *td) 103{ 104 int ret; 105 106 thread_lock(td); 107 ret = sched_is_bound(td); 108 thread_unlock(td); 109 return (ret); 110} 111 112/* 113 * Switch to target cpu to run. 114 */ 115static void 116set_cpu(int cpu, struct thread *td) 117{ 118 119 KASSERT(cpu >= 0 && cpu < mp_ncpus && cpu_enabled(cpu), 120 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 121 thread_lock(td); 122 sched_bind(td, cpu); 123 thread_unlock(td); 124 KASSERT(td->td_oncpu == cpu, 125 ("[cpuctl,%d]: cannot bind to target cpu %d", __LINE__, cpu)); 126} 127 128static void 129restore_cpu(int oldcpu, int is_bound, struct thread *td) 130{ 131 132 KASSERT(oldcpu >= 0 && oldcpu < mp_ncpus && cpu_enabled(oldcpu), 133 ("[cpuctl,%d]: bad cpu number %d", __LINE__, oldcpu)); 134 thread_lock(td); 135 if (is_bound == 0) 136 sched_unbind(td); 137 else 138 sched_bind(td, oldcpu); 139 thread_unlock(td); 140} 141 142int 143cpuctl_ioctl(struct cdev *dev, u_long cmd, caddr_t data, 144 int flags, struct thread *td) 145{ 146 int ret; 147 int cpu = dev2unit(dev); 148 149 if (cpu >= mp_ncpus || !cpu_enabled(cpu)) { 150 DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu); 151 return (ENXIO); 152 } 153 /* Require write flag for "write" requests. */ 154 if ((cmd == CPUCTL_WRMSR || cmd == CPUCTL_UPDATE) && 155 ((flags & FWRITE) == 0)) 156 return (EPERM); 157 switch (cmd) { 158 case CPUCTL_RDMSR: 159 ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td); 160 break; 161 case CPUCTL_MSRSBIT: 162 case CPUCTL_MSRCBIT: 163 case CPUCTL_WRMSR: 164 ret = priv_check(td, PRIV_CPUCTL_WRMSR); 165 if (ret != 0) 166 goto fail; 167 ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td); 168 break; 169 case CPUCTL_CPUID: 170 ret = cpuctl_do_cpuid(cpu, (cpuctl_cpuid_args_t *)data, td); 171 break; 172 case CPUCTL_UPDATE: 173 ret = priv_check(td, PRIV_CPUCTL_UPDATE); 174 if (ret != 0) 175 goto fail; 176 ret = cpuctl_do_update(cpu, (cpuctl_update_args_t *)data, td); 177 break; 178 default: 179 ret = EINVAL; 180 break; 181 } 182fail: 183 return (ret); 184} 185 186/* 187 * Actually perform cpuid operation. 188 */ 189static int 190cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td) 191{ 192 int is_bound = 0; 193 int oldcpu; 194 195 KASSERT(cpu >= 0 && cpu < mp_ncpus, 196 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 197 198 /* Explicitly clear cpuid data to avoid returning stale info. */ 199 bzero(data->data, sizeof(data->data)); 200 DPRINTF("[cpuctl,%d]: retriving cpuid level %#0x for %d cpu\n", 201 __LINE__, data->level, cpu); 202 oldcpu = td->td_oncpu; 203 is_bound = cpu_sched_is_bound(td); 204 set_cpu(cpu, td); 205 do_cpuid(data->level, data->data); 206 restore_cpu(oldcpu, is_bound, td); 207 return (0); 208} 209 210/* 211 * Actually perform MSR operations. 212 */ 213static int 214cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td) 215{ 216 uint64_t reg; 217 int is_bound = 0; 218 int oldcpu; 219 int ret; 220 221 KASSERT(cpu >= 0 && cpu < mp_ncpus, 222 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 223 224 /* 225 * Explicitly clear cpuid data to avoid returning stale 226 * info 227 */ 228 DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__, 229 data->msr, cpu); 230 oldcpu = td->td_oncpu; 231 is_bound = cpu_sched_is_bound(td); 232 set_cpu(cpu, td); 233 if (cmd == CPUCTL_RDMSR) { 234 data->data = 0; 235 ret = rdmsr_safe(data->msr, &data->data); 236 } else if (cmd == CPUCTL_WRMSR) { 237 ret = wrmsr_safe(data->msr, data->data); 238 } else if (cmd == CPUCTL_MSRSBIT) { 239 critical_enter(); 240 ret = rdmsr_safe(data->msr, ®); 241 if (ret == 0) 242 ret = wrmsr_safe(data->msr, reg | data->data); 243 critical_exit(); 244 } else if (cmd == CPUCTL_MSRCBIT) { 245 critical_enter(); 246 ret = rdmsr_safe(data->msr, ®); 247 if (ret == 0) 248 ret = wrmsr_safe(data->msr, reg & ~data->data); 249 critical_exit(); 250 } else 251 panic("[cpuctl,%d]: unknown operation requested: %lu", __LINE__, cmd); 252 restore_cpu(oldcpu, is_bound, td); 253 return (ret); 254} 255 256/* 257 * Actually perform microcode update. 258 */ 259static int 260cpuctl_do_update(int cpu, cpuctl_update_args_t *data, struct thread *td) 261{ 262 cpuctl_cpuid_args_t args = { 263 .level = 0, 264 }; 265 char vendor[13]; 266 int ret; 267 268 KASSERT(cpu >= 0 && cpu < mp_ncpus, 269 ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu)); 270 DPRINTF("[cpuctl,%d]: XXX %d", __LINE__, cpu); 271 272 ret = cpuctl_do_cpuid(cpu, &args, td); 273 if (ret != 0) { 274 DPRINTF("[cpuctl,%d]: cannot retrive cpuid info for cpu %d", 275 __LINE__, cpu); 276 return (ENXIO); 277 } 278 ((uint32_t *)vendor)[0] = args.data[1]; 279 ((uint32_t *)vendor)[1] = args.data[3]; 280 ((uint32_t *)vendor)[2] = args.data[2]; 281 vendor[12] = '\0'; 282 if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) == 0) 283 ret = update_intel(cpu, data, td); 284 else if(strncmp(vendor, INTEL_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0) 285 ret = update_amd(cpu, data, td); 286 else 287 ret = ENXIO; 288 return (ret); 289} 290 291static int 292update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td) 293{ 294 void *ptr = NULL; 295 uint64_t rev0, rev1; 296 uint32_t tmp[4]; 297 int is_bound = 0; 298 int oldcpu; 299 int ret; 300 301 if (args->size == 0 || args->data == NULL) { 302 DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__); 303 return (EINVAL); 304 } 305 if (args->size > UCODE_SIZE_MAX) { 306 DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__); 307 return (EINVAL); 308 } 309 310 /* 311 * 16 byte alignment required. 312 */ 313 ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK); 314 ptr = (void *)(16 + ((intptr_t)ptr & ~0xf)); 315 if (copyin(args->data, ptr, args->size) != 0) { 316 DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed", 317 __LINE__, args->data, ptr, args->size); 318 ret = EFAULT; 319 goto fail; 320 } 321 oldcpu = td->td_oncpu; 322 is_bound = cpu_sched_is_bound(td); 323 set_cpu(cpu, td); 324 critical_enter(); 325 rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current micorcode revision. */ 326 327 /* 328 * Perform update. 329 */ 330 wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr)); 331 wrmsr_safe(MSR_BIOS_SIGN, 0); 332 333 /* 334 * Serialize instruction flow. 335 */ 336 do_cpuid(0, tmp); 337 critical_exit(); 338 rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new micorcode revision. */ 339 restore_cpu(oldcpu, is_bound, td); 340 if (rev1 > rev0) 341 ret = 0; 342 else 343 ret = EEXIST; 344fail: 345 if (ptr != NULL) 346 contigfree(ptr, args->size, M_CPUCTL); 347 return (ret); 348} 349 350static int 351update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td) 352{ 353 void *ptr = NULL; 354 uint32_t tmp[4]; 355 int is_bound = 0; 356 int oldcpu; 357 int ret; 358 359 if (args->size == 0 || args->data == NULL) { 360 DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__); 361 return (EINVAL); 362 } 363 if (args->size > UCODE_SIZE_MAX) { 364 DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__); 365 return (EINVAL); 366 } 367 /* 368 * XXX Might not require contignous address space - needs check 369 */ 370 ptr = contigmalloc(args->size, M_CPUCTL, 0, 0, 0xffffffff, 16, 0); 371 if (ptr == NULL) { 372 DPRINTF("[cpuctl,%d]: cannot allocate %zd bytes of memory", 373 __LINE__, args->size); 374 return (ENOMEM); 375 } 376 if (copyin(args->data, ptr, args->size) != 0) { 377 DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed", 378 __LINE__, args->data, ptr, args->size); 379 ret = EFAULT; 380 goto fail; 381 } 382 oldcpu = td->td_oncpu; 383 is_bound = cpu_sched_is_bound(td); 384 set_cpu(cpu, td); 385 critical_enter(); 386 387 /* 388 * Perform update. 389 */ 390 wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)ptr); 391 392 /* 393 * Serialize instruction flow. 394 */ 395 do_cpuid(0, tmp); 396 critical_exit(); 397 restore_cpu(oldcpu, is_bound, td); 398 ret = 0; 399fail: 400 if (ptr != NULL) 401 contigfree(ptr, args->size, M_CPUCTL); 402 return (ret); 403} 404 405int 406cpuctl_open(struct cdev *dev, int flags, int fmt __unused, struct thread *td) 407{ 408 int ret = 0; 409 int cpu; 410 411 cpu = dev2unit(dev); 412 if (cpu >= mp_ncpus || !cpu_enabled(cpu)) { 413 DPRINTF("[cpuctl,%d]: incorrect cpu number %d\n", __LINE__, 414 cpu); 415 return (ENXIO); 416 } 417 if (flags & FWRITE) 418 ret = securelevel_gt(td->td_ucred, 0); 419 return (ret); 420} 421 422static int 423cpuctl_modevent(module_t mod __unused, int type, void *data __unused) 424{ 425 int cpu; 426 427 switch(type) { 428 case MOD_LOAD: 429 if ((cpu_feature & CPUID_MSR) == 0) { 430 if (bootverbose) 431 printf("cpuctl: not available.\n"); 432 return (ENODEV); 433 } 434 if (bootverbose) 435 printf("cpuctl: access to MSR registers/cpuid info.\n"); 436 cpuctl_devs = (struct cdev **)malloc(sizeof(void *) * mp_ncpus, 437 M_CPUCTL, M_WAITOK | M_ZERO); 438 if (cpuctl_devs == NULL) { 439 DPRINTF("[cpuctl,%d]: cannot allocate memory\n", 440 __LINE__); 441 return (ENOMEM); 442 } 443 for (cpu = 0; cpu < mp_ncpus; cpu++) 444 if (cpu_enabled(cpu)) 445 cpuctl_devs[cpu] = make_dev(&cpuctl_cdevsw, cpu, 446 UID_ROOT, GID_KMEM, 0640, "cpuctl%d", cpu); 447 break; 448 case MOD_UNLOAD: 449 for (cpu = 0; cpu < mp_ncpus; cpu++) { 450 if (cpuctl_devs[cpu] != NULL) 451 destroy_dev(cpuctl_devs[cpu]); 452 } 453 free(cpuctl_devs, M_CPUCTL); 454 break; 455 case MOD_SHUTDOWN: 456 break; 457 default: 458 return (EOPNOTSUPP); 459 } 460 return (0); 461} 462 463DEV_MODULE(cpuctl, cpuctl_modevent, NULL); 464MODULE_VERSION(cpuctl, CPUCTL_VERSION); 465