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 */ 37struct 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 */ 49unsigned int host_info_eax; 50unsigned int host_info_ebx; 51unsigned int host_info_ecx; 52unsigned int host_info_edx; 53 54static 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 */ 94static u64 do_hypercall(u64 control, void *input, void *output) 95{ 96#ifdef CONFIG_X86_64 97 u64 hv_status = 0; 98 u64 input_address = (input) ? virt_to_phys(input) : 0; 99 u64 output_address = (output) ? virt_to_phys(output) : 0; 100 void *hypercall_page = hv_context.hypercall_page; 101 102 __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); 103 __asm__ __volatile__("call *%3" : "=a" (hv_status) : 104 "c" (control), "d" (input_address), 105 "m" (hypercall_page)); 106 107 return hv_status; 108 109#else 110 111 u32 control_hi = control >> 32; 112 u32 control_lo = control & 0xFFFFFFFF; 113 u32 hv_status_hi = 1; 114 u32 hv_status_lo = 1; 115 u64 input_address = (input) ? virt_to_phys(input) : 0; 116 u32 input_address_hi = input_address >> 32; 117 u32 input_address_lo = input_address & 0xFFFFFFFF; 118 u64 output_address = (output) ? virt_to_phys(output) : 0; 119 u32 output_address_hi = output_address >> 32; 120 u32 output_address_lo = output_address & 0xFFFFFFFF; 121 void *hypercall_page = hv_context.hypercall_page; 122 123 __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), 124 "=a"(hv_status_lo) : "d" (control_hi), 125 "a" (control_lo), "b" (input_address_hi), 126 "c" (input_address_lo), "D"(output_address_hi), 127 "S"(output_address_lo), "m" (hypercall_page)); 128 129 return hv_status_lo | ((u64)hv_status_hi << 32); 130#endif /* !x86_64 */ 131} 132 133/* 134 * hv_init - Main initialization routine. 135 * 136 * This routine must be called before any other routines in here are called 137 */ 138int hv_init(void) 139{ 140 int max_leaf; 141 union hv_x64_msr_hypercall_contents hypercall_msr; 142 void *virtaddr = NULL; 143 144 memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS); 145 memset(hv_context.synic_message_page, 0, 146 sizeof(void *) * NR_CPUS); 147 memset(hv_context.post_msg_page, 0, 148 sizeof(void *) * NR_CPUS); 149 memset(hv_context.vp_index, 0, 150 sizeof(int) * NR_CPUS); 151 memset(hv_context.event_dpc, 0, 152 sizeof(void *) * NR_CPUS); 153 memset(hv_context.clk_evt, 0, 154 sizeof(void *) * NR_CPUS); 155 156 max_leaf = query_hypervisor_info(); 157 158 /* 159 * Write our OS ID. 160 */ 161 hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0); 162 wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); 163 164 /* See if the hypercall page is already set */ 165 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 166 167 virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); 168 169 if (!virtaddr) 170 goto cleanup; 171 172 hypercall_msr.enable = 1; 173 174 hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr); 175 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 176 177 /* Confirm that hypercall page did get setup. */ 178 hypercall_msr.as_uint64 = 0; 179 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 180 181 if (!hypercall_msr.enable) 182 goto cleanup; 183 184 hv_context.hypercall_page = virtaddr; 185 186 return 0; 187 188cleanup: 189 if (virtaddr) { 190 if (hypercall_msr.enable) { 191 hypercall_msr.as_uint64 = 0; 192 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 193 } 194 195 vfree(virtaddr); 196 } 197 198 return -ENOTSUPP; 199} 200 201/* 202 * hv_cleanup - Cleanup routine. 203 * 204 * This routine is called normally during driver unloading or exiting. 205 */ 206void hv_cleanup(void) 207{ 208 union hv_x64_msr_hypercall_contents hypercall_msr; 209 210 /* Reset our OS id */ 211 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 212 213 if (hv_context.hypercall_page) { 214 hypercall_msr.as_uint64 = 0; 215 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 216 vfree(hv_context.hypercall_page); 217 hv_context.hypercall_page = NULL; 218 } 219} 220 221/* 222 * hv_post_message - Post a message using the hypervisor message IPC. 223 * 224 * This involves a hypercall. 225 */ 226int hv_post_message(union hv_connection_id connection_id, 227 enum hv_message_type message_type, 228 void *payload, size_t payload_size) 229{ 230 231 struct hv_input_post_message *aligned_msg; 232 u16 status; 233 234 if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) 235 return -EMSGSIZE; 236 237 aligned_msg = (struct hv_input_post_message *) 238 hv_context.post_msg_page[get_cpu()]; 239 240 aligned_msg->connectionid = connection_id; 241 aligned_msg->reserved = 0; 242 aligned_msg->message_type = message_type; 243 aligned_msg->payload_size = payload_size; 244 memcpy((void *)aligned_msg->payload, payload, payload_size); 245 246 status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) 247 & 0xFFFF; 248 249 put_cpu(); 250 return status; 251} 252 253 254/* 255 * hv_signal_event - 256 * Signal an event on the specified connection using the hypervisor event IPC. 257 * 258 * This involves a hypercall. 259 */ 260u16 hv_signal_event(void *con_id) 261{ 262 u16 status; 263 264 status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF); 265 266 return status; 267} 268 269static int hv_ce_set_next_event(unsigned long delta, 270 struct clock_event_device *evt) 271{ 272 cycle_t current_tick; 273 274 WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT); 275 276 rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); 277 current_tick += delta; 278 wrmsrl(HV_X64_MSR_STIMER0_COUNT, current_tick); 279 return 0; 280} 281 282static void hv_ce_setmode(enum clock_event_mode mode, 283 struct clock_event_device *evt) 284{ 285 union hv_timer_config timer_cfg; 286 287 switch (mode) { 288 case CLOCK_EVT_MODE_PERIODIC: 289 /* unsupported */ 290 break; 291 292 case CLOCK_EVT_MODE_ONESHOT: 293 timer_cfg.enable = 1; 294 timer_cfg.auto_enable = 1; 295 timer_cfg.sintx = VMBUS_MESSAGE_SINT; 296 wrmsrl(HV_X64_MSR_STIMER0_CONFIG, timer_cfg.as_uint64); 297 break; 298 299 case CLOCK_EVT_MODE_UNUSED: 300 case CLOCK_EVT_MODE_SHUTDOWN: 301 wrmsrl(HV_X64_MSR_STIMER0_COUNT, 0); 302 wrmsrl(HV_X64_MSR_STIMER0_CONFIG, 0); 303 break; 304 case CLOCK_EVT_MODE_RESUME: 305 break; 306 } 307} 308 309static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) 310{ 311 dev->name = "Hyper-V clockevent"; 312 dev->features = CLOCK_EVT_FEAT_ONESHOT; 313 dev->cpumask = cpumask_of(cpu); 314 dev->rating = 1000; 315 /* 316 * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will 317 * result in clockevents_config_and_register() taking additional 318 * references to the hv_vmbus module making it impossible to unload. 319 */ 320 321 dev->set_mode = hv_ce_setmode; 322 dev->set_next_event = hv_ce_set_next_event; 323} 324 325 326int hv_synic_alloc(void) 327{ 328 size_t size = sizeof(struct tasklet_struct); 329 size_t ced_size = sizeof(struct clock_event_device); 330 int cpu; 331 332 for_each_online_cpu(cpu) { 333 hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC); 334 if (hv_context.event_dpc[cpu] == NULL) { 335 pr_err("Unable to allocate event dpc\n"); 336 goto err; 337 } 338 tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu); 339 340 hv_context.clk_evt[cpu] = kzalloc(ced_size, GFP_ATOMIC); 341 if (hv_context.clk_evt[cpu] == NULL) { 342 pr_err("Unable to allocate clock event device\n"); 343 goto err; 344 } 345 hv_init_clockevent_device(hv_context.clk_evt[cpu], cpu); 346 347 hv_context.synic_message_page[cpu] = 348 (void *)get_zeroed_page(GFP_ATOMIC); 349 350 if (hv_context.synic_message_page[cpu] == NULL) { 351 pr_err("Unable to allocate SYNIC message page\n"); 352 goto err; 353 } 354 355 hv_context.synic_event_page[cpu] = 356 (void *)get_zeroed_page(GFP_ATOMIC); 357 358 if (hv_context.synic_event_page[cpu] == NULL) { 359 pr_err("Unable to allocate SYNIC event page\n"); 360 goto err; 361 } 362 363 hv_context.post_msg_page[cpu] = 364 (void *)get_zeroed_page(GFP_ATOMIC); 365 366 if (hv_context.post_msg_page[cpu] == NULL) { 367 pr_err("Unable to allocate post msg page\n"); 368 goto err; 369 } 370 } 371 372 return 0; 373err: 374 return -ENOMEM; 375} 376 377static void hv_synic_free_cpu(int cpu) 378{ 379 kfree(hv_context.event_dpc[cpu]); 380 kfree(hv_context.clk_evt[cpu]); 381 if (hv_context.synic_event_page[cpu]) 382 free_page((unsigned long)hv_context.synic_event_page[cpu]); 383 if (hv_context.synic_message_page[cpu]) 384 free_page((unsigned long)hv_context.synic_message_page[cpu]); 385 if (hv_context.post_msg_page[cpu]) 386 free_page((unsigned long)hv_context.post_msg_page[cpu]); 387} 388 389void hv_synic_free(void) 390{ 391 int cpu; 392 393 for_each_online_cpu(cpu) 394 hv_synic_free_cpu(cpu); 395} 396 397/* 398 * hv_synic_init - Initialize the Synthethic Interrupt Controller. 399 * 400 * If it is already initialized by another entity (ie x2v shim), we need to 401 * retrieve the initialized message and event pages. Otherwise, we create and 402 * initialize the message and event pages. 403 */ 404void hv_synic_init(void *arg) 405{ 406 u64 version; 407 union hv_synic_simp simp; 408 union hv_synic_siefp siefp; 409 union hv_synic_sint shared_sint; 410 union hv_synic_scontrol sctrl; 411 u64 vp_index; 412 413 int cpu = smp_processor_id(); 414 415 if (!hv_context.hypercall_page) 416 return; 417 418 /* Check the version */ 419 rdmsrl(HV_X64_MSR_SVERSION, version); 420 421 /* Setup the Synic's message page */ 422 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 423 simp.simp_enabled = 1; 424 simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu]) 425 >> PAGE_SHIFT; 426 427 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 428 429 /* Setup the Synic's event page */ 430 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 431 siefp.siefp_enabled = 1; 432 siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu]) 433 >> PAGE_SHIFT; 434 435 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 436 437 /* Setup the shared SINT. */ 438 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 439 440 shared_sint.as_uint64 = 0; 441 shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR; 442 shared_sint.masked = false; 443 shared_sint.auto_eoi = true; 444 445 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 446 447 /* Enable the global synic bit */ 448 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 449 sctrl.enable = 1; 450 451 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 452 453 hv_context.synic_initialized = true; 454 455 /* 456 * Setup the mapping between Hyper-V's notion 457 * of cpuid and Linux' notion of cpuid. 458 * This array will be indexed using Linux cpuid. 459 */ 460 rdmsrl(HV_X64_MSR_VP_INDEX, vp_index); 461 hv_context.vp_index[cpu] = (u32)vp_index; 462 463 INIT_LIST_HEAD(&hv_context.percpu_list[cpu]); 464 465 /* 466 * Register the per-cpu clockevent source. 467 */ 468 if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE) 469 clockevents_config_and_register(hv_context.clk_evt[cpu], 470 HV_TIMER_FREQUENCY, 471 HV_MIN_DELTA_TICKS, 472 HV_MAX_MAX_DELTA_TICKS); 473 return; 474} 475 476/* 477 * hv_synic_clockevents_cleanup - Cleanup clockevent devices 478 */ 479void hv_synic_clockevents_cleanup(void) 480{ 481 int cpu; 482 483 if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)) 484 return; 485 486 for_each_online_cpu(cpu) 487 clockevents_unbind_device(hv_context.clk_evt[cpu], cpu); 488} 489 490/* 491 * hv_synic_cleanup - Cleanup routine for hv_synic_init(). 492 */ 493void hv_synic_cleanup(void *arg) 494{ 495 union hv_synic_sint shared_sint; 496 union hv_synic_simp simp; 497 union hv_synic_siefp siefp; 498 union hv_synic_scontrol sctrl; 499 int cpu = smp_processor_id(); 500 501 if (!hv_context.synic_initialized) 502 return; 503 504 /* Turn off clockevent device */ 505 if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE) 506 hv_ce_setmode(CLOCK_EVT_MODE_SHUTDOWN, 507 hv_context.clk_evt[cpu]); 508 509 rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 510 511 shared_sint.masked = 1; 512 513 /* Need to correctly cleanup in the case of SMP!!! */ 514 /* Disable the interrupt */ 515 wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); 516 517 rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 518 simp.simp_enabled = 0; 519 simp.base_simp_gpa = 0; 520 521 wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64); 522 523 rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 524 siefp.siefp_enabled = 0; 525 siefp.base_siefp_gpa = 0; 526 527 wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64); 528 529 /* Disable the global synic bit */ 530 rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 531 sctrl.enable = 0; 532 wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64); 533 534 hv_synic_free_cpu(cpu); 535} 536