1 /* 2 * Copyright (c) 2009, Microsoft Corporation. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple 15 * Place - Suite 330, Boston, MA 02111-1307 USA. 16 * 17 * Authors: 18 * Haiyang Zhang <haiyangz@microsoft.com> 19 * Hank Janssen <hjanssen@microsoft.com> 20 * 21 */ 22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 23 24 #include <linux/kernel.h> 25 #include <linux/mm.h> 26 #include <linux/slab.h> 27 #include <linux/vmalloc.h> 28 #include <linux/hyperv.h> 29 #include <linux/version.h> 30 #include <linux/interrupt.h> 31 #include <linux/clockchips.h> 32 #include <asm/hyperv.h> 33 #include <asm/mshyperv.h> 34 #include "hyperv_vmbus.h" 35 36 /* The one and only */ 37 struct hv_context hv_context = { 38 .synic_initialized = false, 39 .hypercall_page = NULL, 40 }; 41 42 #define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */ 43 #define HV_MAX_MAX_DELTA_TICKS 0xffffffff 44 #define HV_MIN_DELTA_TICKS 1 45 46 /* 47 * query_hypervisor_info - Get version info of the windows hypervisor 48 */ 49 unsigned int host_info_eax; 50 unsigned int host_info_ebx; 51 unsigned int host_info_ecx; 52 unsigned int host_info_edx; 53 54 static int query_hypervisor_info(void) 55 { 56 unsigned int eax; 57 unsigned int ebx; 58 unsigned int ecx; 59 unsigned int edx; 60 unsigned int max_leaf; 61 unsigned int op; 62 63 /* 64 * Its assumed that this is called after confirming that Viridian 65 * is present. Query id and revision. 66 */ 67 eax = 0; 68 ebx = 0; 69 ecx = 0; 70 edx = 0; 71 op = HVCPUID_VENDOR_MAXFUNCTION; 72 cpuid(op, &eax, &ebx, &ecx, &edx); 73 74 max_leaf = eax; 75 76 if (max_leaf >= HVCPUID_VERSION) { 77 eax = 0; 78 ebx = 0; 79 ecx = 0; 80 edx = 0; 81 op = HVCPUID_VERSION; 82 cpuid(op, &eax, &ebx, &ecx, &edx); 83 host_info_eax = eax; 84 host_info_ebx = ebx; 85 host_info_ecx = ecx; 86 host_info_edx = edx; 87 } 88 return max_leaf; 89 } 90 91 /* 92 * do_hypercall- Invoke the specified hypercall 93 */ 94 static u64 do_hypercall(u64 control, void *input, void *output) 95 { 96 u64 input_address = (input) ? virt_to_phys(input) : 0; 97 u64 output_address = (output) ? virt_to_phys(output) : 0; 98 void *hypercall_page = hv_context.hypercall_page; 99 #ifdef CONFIG_X86_64 100 u64 hv_status = 0; 101 102 if (!hypercall_page) 103 return (u64)ULLONG_MAX; 104 105 __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); 106 __asm__ __volatile__("call *%3" : "=a" (hv_status) : 107 "c" (control), "d" (input_address), 108 "m" (hypercall_page)); 109 110 return hv_status; 111 112 #else 113 114 u32 control_hi = control >> 32; 115 u32 control_lo = control & 0xFFFFFFFF; 116 u32 hv_status_hi = 1; 117 u32 hv_status_lo = 1; 118 u32 input_address_hi = input_address >> 32; 119 u32 input_address_lo = input_address & 0xFFFFFFFF; 120 u32 output_address_hi = output_address >> 32; 121 u32 output_address_lo = output_address & 0xFFFFFFFF; 122 123 if (!hypercall_page) 124 return (u64)ULLONG_MAX; 125 126 __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), 127 "=a"(hv_status_lo) : "d" (control_hi), 128 "a" (control_lo), "b" (input_address_hi), 129 "c" (input_address_lo), "D"(output_address_hi), 130 "S"(output_address_lo), "m" (hypercall_page)); 131 132 return hv_status_lo | ((u64)hv_status_hi << 32); 133 #endif /* !x86_64 */ 134 } 135 136 #ifdef CONFIG_X86_64 137 static cycle_t read_hv_clock_tsc(struct clocksource *arg) 138 { 139 cycle_t current_tick; 140 struct ms_hyperv_tsc_page *tsc_pg = hv_context.tsc_page; 141 142 if (tsc_pg->tsc_sequence != -1) { 143 /* 144 * Use the tsc page to compute the value. 145 */ 146 147 while (1) { 148 cycle_t tmp; 149 u32 sequence = tsc_pg->tsc_sequence; 150 u64 cur_tsc; 151 u64 scale = tsc_pg->tsc_scale; 152 s64 offset = tsc_pg->tsc_offset; 153 154 rdtscll(cur_tsc); 155 /* current_tick = ((cur_tsc *scale) >> 64) + offset */ 156 asm("mulq %3" 157 : "=d" (current_tick), "=a" (tmp) 158 : "a" (cur_tsc), "r" (scale)); 159 160 current_tick += offset; 161 if (tsc_pg->tsc_sequence == sequence) 162 return current_tick; 163 164 if (tsc_pg->tsc_sequence != -1) 165 continue; 166 /* 167 * Fallback using MSR method. 168 */ 169 break; 170 } 171 } 172 rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); 173 return current_tick; 174 } 175 176 static struct clocksource hyperv_cs_tsc = { 177 .name = "hyperv_clocksource_tsc_page", 178 .rating = 425, 179 .read = read_hv_clock_tsc, 180 .mask = CLOCKSOURCE_MASK(64), 181 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 182 }; 183 #endif 184 185 186 /* 187 * hv_init - Main initialization routine. 188 * 189 * This routine must be called before any other routines in here are called 190 */ 191 int hv_init(void) 192 { 193 int max_leaf; 194 union hv_x64_msr_hypercall_contents hypercall_msr; 195 union hv_x64_msr_hypercall_contents tsc_msr; 196 void *virtaddr = NULL; 197 void *va_tsc = NULL; 198 199 memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS); 200 memset(hv_context.synic_message_page, 0, 201 sizeof(void *) * NR_CPUS); 202 memset(hv_context.post_msg_page, 0, 203 sizeof(void *) * NR_CPUS); 204 memset(hv_context.vp_index, 0, 205 sizeof(int) * NR_CPUS); 206 memset(hv_context.event_dpc, 0, 207 sizeof(void *) * NR_CPUS); 208 memset(hv_context.clk_evt, 0, 209 sizeof(void *) * NR_CPUS); 210 211 max_leaf = query_hypervisor_info(); 212 213 /* 214 * Write our OS ID. 215 */ 216 hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0); 217 wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); 218 219 /* See if the hypercall page is already set */ 220 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 221 222 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 223 224 if (!virtaddr) 225 goto cleanup; 226 227 hypercall_msr.enable = 1; 228 229 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 230 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 231 232 /* Confirm that hypercall page did get setup. */ 233 hypercall_msr.as_uint64 = 0; 234 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 235 236 if (!hypercall_msr.enable) 237 goto cleanup; 238 239 hv_context.hypercall_page = virtaddr; 240 241 #ifdef CONFIG_X86_64 242 if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) { 243 va_tsc = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); 244 if (!va_tsc) 245 goto cleanup; 246 hv_context.tsc_page = va_tsc; 247 248 rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); 249 250 tsc_msr.enable = 1; 251 tsc_msr.guest_physical_address = vmalloc_to_pfn(va_tsc); 252 253 wrmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); 254 clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100); 255 } 256 #endif 257 return 0; 258 259 cleanup: 260 if (virtaddr) { 261 if (hypercall_msr.enable) { 262 hypercall_msr.as_uint64 = 0; 263 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 264 } 265 266 vfree(virtaddr); 267 } 268 269 return -ENOTSUPP; 270 } 271 272 /* 273 * hv_cleanup - Cleanup routine. 274 * 275 * This routine is called normally during driver unloading or exiting. 276 */ 277 void hv_cleanup(void) 278 { 279 union hv_x64_msr_hypercall_contents hypercall_msr; 280 281 /* Reset our OS id */ 282 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 283 284 if (hv_context.hypercall_page) { 285 hypercall_msr.as_uint64 = 0; 286 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 287 vfree(hv_context.hypercall_page); 288 hv_context.hypercall_page = NULL; 289 } 290 291 #ifdef CONFIG_X86_64 292 /* 293 * Cleanup the TSC page based CS. 294 */ 295 if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) { 296 clocksource_change_rating(&hyperv_cs_tsc, 10); 297 clocksource_unregister(&hyperv_cs_tsc); 298 299 hypercall_msr.as_uint64 = 0; 300 wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64); 301 vfree(hv_context.tsc_page); 302 hv_context.tsc_page = NULL; 303 } 304 #endif 305 } 306 307 /* 308 * hv_post_message - Post a message using the hypervisor message IPC. 309 * 310 * This involves a hypercall. 311 */ 312 int hv_post_message(union hv_connection_id connection_id, 313 enum hv_message_type message_type, 314 void *payload, size_t payload_size) 315 { 316 317 struct hv_input_post_message *aligned_msg; 318 u16 status; 319 320 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 321 return -EMSGSIZE; 322 323 aligned_msg = (struct hv_input_post_message *) 324 hv_context.post_msg_page[get_cpu()]; 325 326 aligned_msg->connectionid = connection_id; 327 aligned_msg->reserved = 0; 328 aligned_msg->message_type = message_type; 329 aligned_msg->payload_size = payload_size; 330 memcpy((void *)aligned_msg->payload, payload, payload_size); 331 332 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 333 & 0xFFFF; 334 335 put_cpu(); 336 return status; 337 } 338 339 340 /* 341 * hv_signal_event - 342 * Signal an event on the specified connection using the hypervisor event IPC. 343 * 344 * This involves a hypercall. 345 */ 346 u16 hv_signal_event(void *con_id) 347 { 348 u16 status; 349 350 status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF); 351 352 return status; 353 } 354 355 static int hv_ce_set_next_event(unsigned long delta, 356 struct clock_event_device *evt) 357 { 358 cycle_t current_tick; 359 360 WARN_ON(!clockevent_state_oneshot(evt)); 361 362 rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); 363 current_tick += delta; 364 wrmsrl(HV_X64_MSR_STIMER0_COUNT, current_tick); 365 return 0; 366 } 367 368 static int hv_ce_shutdown(struct clock_event_device *evt) 369 { 370 wrmsrl(HV_X64_MSR_STIMER0_COUNT, 0); 371 wrmsrl(HV_X64_MSR_STIMER0_CONFIG, 0); 372 373 return 0; 374 } 375 376 static int hv_ce_set_oneshot(struct clock_event_device *evt) 377 { 378 union hv_timer_config timer_cfg; 379 380 timer_cfg.enable = 1; 381 timer_cfg.auto_enable = 1; 382 timer_cfg.sintx = VMBUS_MESSAGE_SINT; 383 wrmsrl(HV_X64_MSR_STIMER0_CONFIG, timer_cfg.as_uint64); 384 385 return 0; 386 } 387 388 static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) 389 { 390 dev->name = "Hyper-V clockevent"; 391 dev->features = CLOCK_EVT_FEAT_ONESHOT; 392 dev->cpumask = cpumask_of(cpu); 393 dev->rating = 1000; 394 /* 395 * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will 396 * result in clockevents_config_and_register() taking additional 397 * references to the hv_vmbus module making it impossible to unload. 398 */ 399 400 dev->set_state_shutdown = hv_ce_shutdown; 401 dev->set_state_oneshot = hv_ce_set_oneshot; 402 dev->set_next_event = hv_ce_set_next_event; 403 } 404 405 406 int hv_synic_alloc(void) 407 { 408 size_t size = sizeof(struct tasklet_struct); 409 size_t ced_size = sizeof(struct clock_event_device); 410 int cpu; 411 412 hv_context.hv_numa_map = kzalloc(sizeof(struct cpumask) * nr_node_ids, 413 GFP_ATOMIC); 414 if (hv_context.hv_numa_map == NULL) { 415 pr_err("Unable to allocate NUMA map\n"); 416 goto err; 417 } 418 419 for_each_online_cpu(cpu) { 420 hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC); 421 if (hv_context.event_dpc[cpu] == NULL) { 422 pr_err("Unable to allocate event dpc\n"); 423 goto err; 424 } 425 tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu); 426 427 hv_context.clk_evt[cpu] = kzalloc(ced_size, GFP_ATOMIC); 428 if (hv_context.clk_evt[cpu] == NULL) { 429 pr_err("Unable to allocate clock event device\n"); 430 goto err; 431 } 432 433 hv_init_clockevent_device(hv_context.clk_evt[cpu], cpu); 434 435 hv_context.synic_message_page[cpu] = 436 (void *)get_zeroed_page(GFP_ATOMIC); 437 438 if (hv_context.synic_message_page[cpu] == NULL) { 439 pr_err("Unable to allocate SYNIC message page\n"); 440 goto err; 441 } 442 443 hv_context.synic_event_page[cpu] = 444 (void *)get_zeroed_page(GFP_ATOMIC); 445 446 if (hv_context.synic_event_page[cpu] == NULL) { 447 pr_err("Unable to allocate SYNIC event page\n"); 448 goto err; 449 } 450 451 hv_context.post_msg_page[cpu] = 452 (void *)get_zeroed_page(GFP_ATOMIC); 453 454 if (hv_context.post_msg_page[cpu] == NULL) { 455 pr_err("Unable to allocate post msg page\n"); 456 goto err; 457 } 458 } 459 460 return 0; 461 err: 462 return -ENOMEM; 463 } 464 465 static void hv_synic_free_cpu(int cpu) 466 { 467 kfree(hv_context.event_dpc[cpu]); 468 kfree(hv_context.clk_evt[cpu]); 469 if (hv_context.synic_event_page[cpu]) 470 free_page((unsigned long)hv_context.synic_event_page[cpu]); 471 if (hv_context.synic_message_page[cpu]) 472 free_page((unsigned long)hv_context.synic_message_page[cpu]); 473 if (hv_context.post_msg_page[cpu]) 474 free_page((unsigned long)hv_context.post_msg_page[cpu]); 475 } 476 477 void hv_synic_free(void) 478 { 479 int cpu; 480 481 kfree(hv_context.hv_numa_map); 482 for_each_online_cpu(cpu) 483 hv_synic_free_cpu(cpu); 484 } 485 486 /* 487 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 488 * 489 * If it is already initialized by another entity (ie x2v shim), we need to 490 * retrieve the initialized message and event pages. Otherwise, we create and 491 * initialize the message and event pages. 492 */ 493 void hv_synic_init(void *arg) 494 { 495 u64 version; 496 union hv_synic_simp simp; 497 union hv_synic_siefp siefp; 498 union hv_synic_sint shared_sint; 499 union hv_synic_scontrol sctrl; 500 u64 vp_index; 501 502 int cpu = smp_processor_id(); 503 504 if (!hv_context.hypercall_page) 505 return; 506 507 /* Check the version */ 508 rdmsrl(HV_X64_MSR_SVERSION, version); 509 510 /* Setup the Synic's message page */ 511 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 512 simp.simp_enabled = 1; 513 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 514 >> PAGE_SHIFT; 515 516 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 517 518 /* Setup the Synic's event page */ 519 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 520 siefp.siefp_enabled = 1; 521 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 522 >> PAGE_SHIFT; 523 524 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 525 526 /* Setup the shared SINT. */ 527 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 528 529 shared_sint.as_uint64 = 0; 530 shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR; 531 shared_sint.masked = false; 532 shared_sint.auto_eoi = true; 533 534 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 535 536 /* Enable the global synic bit */ 537 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 538 sctrl.enable = 1; 539 540 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 541 542 hv_context.synic_initialized = true; 543 544 /* 545 * Setup the mapping between Hyper-V's notion 546 * of cpuid and Linux' notion of cpuid. 547 * This array will be indexed using Linux cpuid. 548 */ 549 rdmsrl(HV_X64_MSR_VP_INDEX, vp_index); 550 hv_context.vp_index[cpu] = (u32)vp_index; 551 552 INIT_LIST_HEAD(&hv_context.percpu_list[cpu]); 553 554 /* 555 * Register the per-cpu clockevent source. 556 */ 557 if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE) 558 clockevents_config_and_register(hv_context.clk_evt[cpu], 559 HV_TIMER_FREQUENCY, 560 HV_MIN_DELTA_TICKS, 561 HV_MAX_MAX_DELTA_TICKS); 562 return; 563 } 564 565 /* 566 * hv_synic_clockevents_cleanup - Cleanup clockevent devices 567 */ 568 void hv_synic_clockevents_cleanup(void) 569 { 570 int cpu; 571 572 if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)) 573 return; 574 575 for_each_online_cpu(cpu) 576 clockevents_unbind_device(hv_context.clk_evt[cpu], cpu); 577 } 578 579 /* 580 * hv_synic_cleanup - Cleanup routine for hv_synic_init(). 581 */ 582 void hv_synic_cleanup(void *arg) 583 { 584 union hv_synic_sint shared_sint; 585 union hv_synic_simp simp; 586 union hv_synic_siefp siefp; 587 union hv_synic_scontrol sctrl; 588 int cpu = smp_processor_id(); 589 590 if (!hv_context.synic_initialized) 591 return; 592 593 /* Turn off clockevent device */ 594 if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE) 595 hv_ce_shutdown(hv_context.clk_evt[cpu]); 596 597 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 598 599 shared_sint.masked = 1; 600 601 /* Need to correctly cleanup in the case of SMP!!! */ 602 /* Disable the interrupt */ 603 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 604 605 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 606 simp.simp_enabled = 0; 607 simp.base_simp_gpa = 0; 608 609 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 610 611 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 612 siefp.siefp_enabled = 0; 613 siefp.base_siefp_gpa = 0; 614 615 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 616 617 /* Disable the global synic bit */ 618 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 619 sctrl.enable = 0; 620 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 621 } 622