arch/arm64/kvm/arch_timer.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 ARM Ltd.
   4  * Author: Marc Zyngier <marc.zyngier@arm.com>
   5  */
   6
   7 #include <linux/cpu.h>
   8 #include <linux/kvm.h>
   9 #include <linux/kvm_host.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/irq.h>
  12 #include <linux/uaccess.h>
  13
  14 #include <clocksource/arm_arch_timer.h>
  15 #include <asm/arch_timer.h>
  16 #include <asm/kvm_emulate.h>
  17 #include <asm/kvm_hyp.h>
  18
  19 #include <kvm/arm_vgic.h>
  20 #include <kvm/arm_arch_timer.h>
  21
  22 #include "trace.h"
  23
  24 static struct timecounter *timecounter;
  25 static unsigned int host_vtimer_irq;
  26 static unsigned int host_ptimer_irq;
  27 static u32 host_vtimer_irq_flags;
  28 static u32 host_ptimer_irq_flags;
  29
  30 static DEFINE_STATIC_KEY_FALSE(has_gic_active_state);
  31
  32 static const struct kvm_irq_level default_ptimer_irq = {
  33         .irq    = 30,
  34         .level  = 1,
  35 };
  36
  37 static const struct kvm_irq_level default_vtimer_irq = {
  38         .irq    = 27,
  39         .level  = 1,
  40 };
  41
  42 static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx);
  43 static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
  44                                  struct arch_timer_context *timer_ctx);
  45 static bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx);
  46 static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
  47                                 struct arch_timer_context *timer,
  48                                 enum kvm_arch_timer_regs treg,
  49                                 u64 val);
  50 static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
  51                               struct arch_timer_context *timer,
  52                               enum kvm_arch_timer_regs treg);
  53
  54 u32 timer_get_ctl(struct arch_timer_context *ctxt)
  55 {
  56         struct kvm_vcpu *vcpu = ctxt->vcpu;
  57
  58         switch(arch_timer_ctx_index(ctxt)) {
  59         case TIMER_VTIMER:
  60                 return __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
  61         case TIMER_PTIMER:
  62                 return __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
  63         default:
  64                 WARN_ON(1);
  65                 return 0;
  66         }
  67 }
  68
  69 u64 timer_get_cval(struct arch_timer_context *ctxt)
  70 {
  71         struct kvm_vcpu *vcpu = ctxt->vcpu;
  72
  73         switch(arch_timer_ctx_index(ctxt)) {
  74         case TIMER_VTIMER:
  75                 return __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
  76         case TIMER_PTIMER:
  77                 return __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
  78         default:
  79                 WARN_ON(1);
  80                 return 0;
  81         }
  82 }
  83
  84 static u64 timer_get_offset(struct arch_timer_context *ctxt)
  85 {
  86         struct kvm_vcpu *vcpu = ctxt->vcpu;
  87
  88         switch(arch_timer_ctx_index(ctxt)) {
  89         case TIMER_VTIMER:
  90                 return __vcpu_sys_reg(vcpu, CNTVOFF_EL2);
  91         default:
  92                 return 0;
  93         }
  94 }
  95
  96 static void timer_set_ctl(struct arch_timer_context *ctxt, u32 ctl)
  97 {
  98         struct kvm_vcpu *vcpu = ctxt->vcpu;
  99
 100         switch(arch_timer_ctx_index(ctxt)) {
 101         case TIMER_VTIMER:
 102                 __vcpu_sys_reg(vcpu, CNTV_CTL_EL0) = ctl;
 103                 break;
 104         case TIMER_PTIMER:
 105                 __vcpu_sys_reg(vcpu, CNTP_CTL_EL0) = ctl;
 106                 break;
 107         default:
 108                 WARN_ON(1);
 109         }
 110 }
 111
 112 static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval)
 113 {
 114         struct kvm_vcpu *vcpu = ctxt->vcpu;
 115
 116         switch(arch_timer_ctx_index(ctxt)) {
 117         case TIMER_VTIMER:
 118                 __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0) = cval;
 119                 break;
 120         case TIMER_PTIMER:
 121                 __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0) = cval;
 122                 break;
 123         default:
 124                 WARN_ON(1);
 125         }
 126 }
 127
 128 static void timer_set_offset(struct arch_timer_context *ctxt, u64 offset)
 129 {
 130         struct kvm_vcpu *vcpu = ctxt->vcpu;
 131
 132         switch(arch_timer_ctx_index(ctxt)) {
 133         case TIMER_VTIMER:
 134                 __vcpu_sys_reg(vcpu, CNTVOFF_EL2) = offset;
 135                 break;
 136         default:
 137                 WARN(offset, "timer %ld\n", arch_timer_ctx_index(ctxt));
 138         }
 139 }
 140
 141 u64 kvm_phys_timer_read(void)
 142 {
 143         return timecounter->cc->read(timecounter->cc);
 144 }
 145
 146 static void get_timer_map(struct kvm_vcpu *vcpu, struct timer_map *map)
 147 {
 148         if (has_vhe()) {
 149                 map->direct_vtimer = vcpu_vtimer(vcpu);
 150                 map->direct_ptimer = vcpu_ptimer(vcpu);
 151                 map->emul_ptimer = NULL;
 152         } else {
 153                 map->direct_vtimer = vcpu_vtimer(vcpu);
 154                 map->direct_ptimer = NULL;
 155                 map->emul_ptimer = vcpu_ptimer(vcpu);
 156         }
 157
 158         trace_kvm_get_timer_map(vcpu->vcpu_id, map);
 159 }
 160
 161 static inline bool userspace_irqchip(struct kvm *kvm)
 162 {
 163         return static_branch_unlikely(&userspace_irqchip_in_use) &&
 164                 unlikely(!irqchip_in_kernel(kvm));
 165 }
 166
 167 static void soft_timer_start(struct hrtimer *hrt, u64 ns)
 168 {
 169         hrtimer_start(hrt, ktime_add_ns(ktime_get(), ns),
 170                       HRTIMER_MODE_ABS_HARD);
 171 }
 172
 173 static void soft_timer_cancel(struct hrtimer *hrt)
 174 {
 175         hrtimer_cancel(hrt);
 176 }
 177
 178 static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
 179 {
 180         struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id;
 181         struct arch_timer_context *ctx;
 182         struct timer_map map;
 183
 184         /*
 185          * We may see a timer interrupt after vcpu_put() has been called which
 186          * sets the CPU's vcpu pointer to NULL, because even though the timer
 187          * has been disabled in timer_save_state(), the hardware interrupt
 188          * signal may not have been retired from the interrupt controller yet.
 189          */
 190         if (!vcpu)
 191                 return IRQ_HANDLED;
 192
 193         get_timer_map(vcpu, &map);
 194
 195         if (irq == host_vtimer_irq)
 196                 ctx = map.direct_vtimer;
 197         else
 198                 ctx = map.direct_ptimer;
 199
 200         if (kvm_timer_should_fire(ctx))
 201                 kvm_timer_update_irq(vcpu, true, ctx);
 202
 203         if (userspace_irqchip(vcpu->kvm) &&
 204             !static_branch_unlikely(&has_gic_active_state))
 205                 disable_percpu_irq(host_vtimer_irq);
 206
 207         return IRQ_HANDLED;
 208 }
 209
 210 static u64 kvm_timer_compute_delta(struct arch_timer_context *timer_ctx)
 211 {
 212         u64 cval, now;
 213
 214         cval = timer_get_cval(timer_ctx);
 215         now = kvm_phys_timer_read() - timer_get_offset(timer_ctx);
 216
 217         if (now < cval) {
 218                 u64 ns;
 219
 220                 ns = cyclecounter_cyc2ns(timecounter->cc,
 221                                          cval - now,
 222                                          timecounter->mask,
 223                                          &timecounter->frac);
 224                 return ns;
 225         }
 226
 227         return 0;
 228 }
 229
 230 static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx)
 231 {
 232         WARN_ON(timer_ctx && timer_ctx->loaded);
 233         return timer_ctx &&
 234                 ((timer_get_ctl(timer_ctx) &
 235                   (ARCH_TIMER_CTRL_IT_MASK | ARCH_TIMER_CTRL_ENABLE)) == ARCH_TIMER_CTRL_ENABLE);
 236 }
 237
 238 /*
 239  * Returns the earliest expiration time in ns among guest timers.
 240  * Note that it will return 0 if none of timers can fire.
 241  */
 242 static u64 kvm_timer_earliest_exp(struct kvm_vcpu *vcpu)
 243 {
 244         u64 min_delta = ULLONG_MAX;
 245         int i;
 246
 247         for (i = 0; i < NR_KVM_TIMERS; i++) {
 248                 struct arch_timer_context *ctx = &vcpu->arch.timer_cpu.timers[i];
 249
 250                 WARN(ctx->loaded, "timer %d loaded\n", i);
 251                 if (kvm_timer_irq_can_fire(ctx))
 252                         min_delta = min(min_delta, kvm_timer_compute_delta(ctx));
 253         }
 254
 255         /* If none of timers can fire, then return 0 */
 256         if (min_delta == ULLONG_MAX)
 257                 return 0;
 258
 259         return min_delta;
 260 }
 261
 262 static enum hrtimer_restart kvm_bg_timer_expire(struct hrtimer *hrt)
 263 {
 264         struct arch_timer_cpu *timer;
 265         struct kvm_vcpu *vcpu;
 266         u64 ns;
 267
 268         timer = container_of(hrt, struct arch_timer_cpu, bg_timer);
 269         vcpu = container_of(timer, struct kvm_vcpu, arch.timer_cpu);
 270
 271         /*
 272          * Check that the timer has really expired from the guest's
 273          * PoV (NTP on the host may have forced it to expire
 274          * early). If we should have slept longer, restart it.
 275          */
 276         ns = kvm_timer_earliest_exp(vcpu);
 277         if (unlikely(ns)) {
 278                 hrtimer_forward_now(hrt, ns_to_ktime(ns));
 279                 return HRTIMER_RESTART;
 280         }
 281
 282         kvm_vcpu_wake_up(vcpu);
 283         return HRTIMER_NORESTART;
 284 }
 285
 286 static enum hrtimer_restart kvm_hrtimer_expire(struct hrtimer *hrt)
 287 {
 288         struct arch_timer_context *ctx;
 289         struct kvm_vcpu *vcpu;
 290         u64 ns;
 291
 292         ctx = container_of(hrt, struct arch_timer_context, hrtimer);
 293         vcpu = ctx->vcpu;
 294
 295         trace_kvm_timer_hrtimer_expire(ctx);
 296
 297         /*
 298          * Check that the timer has really expired from the guest's
 299          * PoV (NTP on the host may have forced it to expire
 300          * early). If not ready, schedule for a later time.
 301          */
 302         ns = kvm_timer_compute_delta(ctx);
 303         if (unlikely(ns)) {
 304                 hrtimer_forward_now(hrt, ns_to_ktime(ns));
 305                 return HRTIMER_RESTART;
 306         }
 307
 308         kvm_timer_update_irq(vcpu, true, ctx);
 309         return HRTIMER_NORESTART;
 310 }
 311
 312 static bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx)
 313 {
 314         enum kvm_arch_timers index;
 315         u64 cval, now;
 316
 317         if (!timer_ctx)
 318                 return false;
 319
 320         index = arch_timer_ctx_index(timer_ctx);
 321
 322         if (timer_ctx->loaded) {
 323                 u32 cnt_ctl = 0;
 324
 325                 switch (index) {
 326                 case TIMER_VTIMER:
 327                         cnt_ctl = read_sysreg_el0(SYS_CNTV_CTL);
 328                         break;
 329                 case TIMER_PTIMER:
 330                         cnt_ctl = read_sysreg_el0(SYS_CNTP_CTL);
 331                         break;
 332                 case NR_KVM_TIMERS:
 333                         /* GCC is braindead */
 334                         cnt_ctl = 0;
 335                         break;
 336                 }
 337
 338                 return  (cnt_ctl & ARCH_TIMER_CTRL_ENABLE) &&
 339                         (cnt_ctl & ARCH_TIMER_CTRL_IT_STAT) &&
 340                        !(cnt_ctl & ARCH_TIMER_CTRL_IT_MASK);
 341         }
 342
 343         if (!kvm_timer_irq_can_fire(timer_ctx))
 344                 return false;
 345
 346         cval = timer_get_cval(timer_ctx);
 347         now = kvm_phys_timer_read() - timer_get_offset(timer_ctx);
 348
 349         return cval <= now;
 350 }
 351
 352 bool kvm_timer_is_pending(struct kvm_vcpu *vcpu)
 353 {
 354         struct timer_map map;
 355
 356         get_timer_map(vcpu, &map);
 357
 358         return kvm_timer_should_fire(map.direct_vtimer) ||
 359                kvm_timer_should_fire(map.direct_ptimer) ||
 360                kvm_timer_should_fire(map.emul_ptimer);
 361 }
 362
 363 /*
 364  * Reflect the timer output level into the kvm_run structure
 365  */
 366 void kvm_timer_update_run(struct kvm_vcpu *vcpu)
 367 {
 368         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 369         struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
 370         struct kvm_sync_regs *regs = &vcpu->run->s.regs;
 371
 372         /* Populate the device bitmap with the timer states */
 373         regs->device_irq_level &= ~(KVM_ARM_DEV_EL1_VTIMER |
 374                                     KVM_ARM_DEV_EL1_PTIMER);
 375         if (kvm_timer_should_fire(vtimer))
 376                 regs->device_irq_level |= KVM_ARM_DEV_EL1_VTIMER;
 377         if (kvm_timer_should_fire(ptimer))
 378                 regs->device_irq_level |= KVM_ARM_DEV_EL1_PTIMER;
 379 }
 380
 381 static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
 382                                  struct arch_timer_context *timer_ctx)
 383 {
 384         int ret;
 385
 386         timer_ctx->irq.level = new_level;
 387         trace_kvm_timer_update_irq(vcpu->vcpu_id, timer_ctx->irq.irq,
 388                                    timer_ctx->irq.level);
 389
 390         if (!userspace_irqchip(vcpu->kvm)) {
 391                 ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
 392                                           timer_ctx->irq.irq,
 393                                           timer_ctx->irq.level,
 394                                           timer_ctx);
 395                 WARN_ON(ret);
 396         }
 397 }
 398
 399 /* Only called for a fully emulated timer */
 400 static void timer_emulate(struct arch_timer_context *ctx)
 401 {
 402         bool should_fire = kvm_timer_should_fire(ctx);
 403
 404         trace_kvm_timer_emulate(ctx, should_fire);
 405
 406         if (should_fire != ctx->irq.level) {
 407                 kvm_timer_update_irq(ctx->vcpu, should_fire, ctx);
 408                 return;
 409         }
 410
 411         /*
 412          * If the timer can fire now, we don't need to have a soft timer
 413          * scheduled for the future.  If the timer cannot fire at all,
 414          * then we also don't need a soft timer.
 415          */
 416         if (!kvm_timer_irq_can_fire(ctx)) {
 417                 soft_timer_cancel(&ctx->hrtimer);
 418                 return;
 419         }
 420
 421         soft_timer_start(&ctx->hrtimer, kvm_timer_compute_delta(ctx));
 422 }
 423
 424 static void timer_save_state(struct arch_timer_context *ctx)
 425 {
 426         struct arch_timer_cpu *timer = vcpu_timer(ctx->vcpu);
 427         enum kvm_arch_timers index = arch_timer_ctx_index(ctx);
 428         unsigned long flags;
 429
 430         if (!timer->enabled)
 431                 return;
 432
 433         local_irq_save(flags);
 434
 435         if (!ctx->loaded)
 436                 goto out;
 437
 438         switch (index) {
 439         case TIMER_VTIMER:
 440                 timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTV_CTL));
 441                 timer_set_cval(ctx, read_sysreg_el0(SYS_CNTV_CVAL));
 442
 443                 /* Disable the timer */
 444                 write_sysreg_el0(0, SYS_CNTV_CTL);
 445                 isb();
 446
 447                 break;
 448         case TIMER_PTIMER:
 449                 timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTP_CTL));
 450                 timer_set_cval(ctx, read_sysreg_el0(SYS_CNTP_CVAL));
 451
 452                 /* Disable the timer */
 453                 write_sysreg_el0(0, SYS_CNTP_CTL);
 454                 isb();
 455
 456                 break;
 457         case NR_KVM_TIMERS:
 458                 BUG();
 459         }
 460
 461         trace_kvm_timer_save_state(ctx);
 462
 463         ctx->loaded = false;
 464 out:
 465         local_irq_restore(flags);
 466 }
 467
 468 /*
 469  * Schedule the background timer before calling kvm_vcpu_block, so that this
 470  * thread is removed from its waitqueue and made runnable when there's a timer
 471  * interrupt to handle.
 472  */
 473 static void kvm_timer_blocking(struct kvm_vcpu *vcpu)
 474 {
 475         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 476         struct timer_map map;
 477
 478         get_timer_map(vcpu, &map);
 479
 480         /*
 481          * If no timers are capable of raising interrupts (disabled or
 482          * masked), then there's no more work for us to do.
 483          */
 484         if (!kvm_timer_irq_can_fire(map.direct_vtimer) &&
 485             !kvm_timer_irq_can_fire(map.direct_ptimer) &&
 486             !kvm_timer_irq_can_fire(map.emul_ptimer))
 487                 return;
 488
 489         /*
 490          * At least one guest time will expire. Schedule a background timer.
 491          * Set the earliest expiration time among the guest timers.
 492          */
 493         soft_timer_start(&timer->bg_timer, kvm_timer_earliest_exp(vcpu));
 494 }
 495
 496 static void kvm_timer_unblocking(struct kvm_vcpu *vcpu)
 497 {
 498         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 499
 500         soft_timer_cancel(&timer->bg_timer);
 501 }
 502
 503 static void timer_restore_state(struct arch_timer_context *ctx)
 504 {
 505         struct arch_timer_cpu *timer = vcpu_timer(ctx->vcpu);
 506         enum kvm_arch_timers index = arch_timer_ctx_index(ctx);
 507         unsigned long flags;
 508
 509         if (!timer->enabled)
 510                 return;
 511
 512         local_irq_save(flags);
 513
 514         if (ctx->loaded)
 515                 goto out;
 516
 517         switch (index) {
 518         case TIMER_VTIMER:
 519                 write_sysreg_el0(timer_get_cval(ctx), SYS_CNTV_CVAL);
 520                 isb();
 521                 write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTV_CTL);
 522                 break;
 523         case TIMER_PTIMER:
 524                 write_sysreg_el0(timer_get_cval(ctx), SYS_CNTP_CVAL);
 525                 isb();
 526                 write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTP_CTL);
 527                 break;
 528         case NR_KVM_TIMERS:
 529                 BUG();
 530         }
 531
 532         trace_kvm_timer_restore_state(ctx);
 533
 534         ctx->loaded = true;
 535 out:
 536         local_irq_restore(flags);
 537 }
 538
 539 static void set_cntvoff(u64 cntvoff)
 540 {
 541         kvm_call_hyp(__kvm_timer_set_cntvoff, cntvoff);
 542 }
 543
 544 static inline void set_timer_irq_phys_active(struct arch_timer_context *ctx, bool active)
 545 {
 546         int r;
 547         r = irq_set_irqchip_state(ctx->host_timer_irq, IRQCHIP_STATE_ACTIVE, active);
 548         WARN_ON(r);
 549 }
 550
 551 static void kvm_timer_vcpu_load_gic(struct arch_timer_context *ctx)
 552 {
 553         struct kvm_vcpu *vcpu = ctx->vcpu;
 554         bool phys_active = false;
 555
 556         /*
 557          * Update the timer output so that it is likely to match the
 558          * state we're about to restore. If the timer expires between
 559          * this point and the register restoration, we'll take the
 560          * interrupt anyway.
 561          */
 562         kvm_timer_update_irq(ctx->vcpu, kvm_timer_should_fire(ctx), ctx);
 563
 564         if (irqchip_in_kernel(vcpu->kvm))
 565                 phys_active = kvm_vgic_map_is_active(vcpu, ctx->irq.irq);
 566
 567         phys_active |= ctx->irq.level;
 568
 569         set_timer_irq_phys_active(ctx, phys_active);
 570 }
 571
 572 static void kvm_timer_vcpu_load_nogic(struct kvm_vcpu *vcpu)
 573 {
 574         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 575
 576         /*
 577          * Update the timer output so that it is likely to match the
 578          * state we're about to restore. If the timer expires between
 579          * this point and the register restoration, we'll take the
 580          * interrupt anyway.
 581          */
 582         kvm_timer_update_irq(vcpu, kvm_timer_should_fire(vtimer), vtimer);
 583
 584         /*
 585          * When using a userspace irqchip with the architected timers and a
 586          * host interrupt controller that doesn't support an active state, we
 587          * must still prevent continuously exiting from the guest, and
 588          * therefore mask the physical interrupt by disabling it on the host
 589          * interrupt controller when the virtual level is high, such that the
 590          * guest can make forward progress.  Once we detect the output level
 591          * being de-asserted, we unmask the interrupt again so that we exit
 592          * from the guest when the timer fires.
 593          */
 594         if (vtimer->irq.level)
 595                 disable_percpu_irq(host_vtimer_irq);
 596         else
 597                 enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
 598 }
 599
 600 void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
 601 {
 602         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 603         struct timer_map map;
 604
 605         if (unlikely(!timer->enabled))
 606                 return;
 607
 608         get_timer_map(vcpu, &map);
 609
 610         if (static_branch_likely(&has_gic_active_state)) {
 611                 kvm_timer_vcpu_load_gic(map.direct_vtimer);
 612                 if (map.direct_ptimer)
 613                         kvm_timer_vcpu_load_gic(map.direct_ptimer);
 614         } else {
 615                 kvm_timer_vcpu_load_nogic(vcpu);
 616         }
 617
 618         set_cntvoff(timer_get_offset(map.direct_vtimer));
 619
 620         kvm_timer_unblocking(vcpu);
 621
 622         timer_restore_state(map.direct_vtimer);
 623         if (map.direct_ptimer)
 624                 timer_restore_state(map.direct_ptimer);
 625
 626         if (map.emul_ptimer)
 627                 timer_emulate(map.emul_ptimer);
 628 }
 629
 630 bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu)
 631 {
 632         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 633         struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
 634         struct kvm_sync_regs *sregs = &vcpu->run->s.regs;
 635         bool vlevel, plevel;
 636
 637         if (likely(irqchip_in_kernel(vcpu->kvm)))
 638                 return false;
 639
 640         vlevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_VTIMER;
 641         plevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_PTIMER;
 642
 643         return kvm_timer_should_fire(vtimer) != vlevel ||
 644                kvm_timer_should_fire(ptimer) != plevel;
 645 }
 646
 647 void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
 648 {
 649         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 650         struct timer_map map;
 651         struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
 652
 653         if (unlikely(!timer->enabled))
 654                 return;
 655
 656         get_timer_map(vcpu, &map);
 657
 658         timer_save_state(map.direct_vtimer);
 659         if (map.direct_ptimer)
 660                 timer_save_state(map.direct_ptimer);
 661
 662         /*
 663          * Cancel soft timer emulation, because the only case where we
 664          * need it after a vcpu_put is in the context of a sleeping VCPU, and
 665          * in that case we already factor in the deadline for the physical
 666          * timer when scheduling the bg_timer.
 667          *
 668          * In any case, we re-schedule the hrtimer for the physical timer when
 669          * coming back to the VCPU thread in kvm_timer_vcpu_load().
 670          */
 671         if (map.emul_ptimer)
 672                 soft_timer_cancel(&map.emul_ptimer->hrtimer);
 673
 674         if (rcuwait_active(wait))
 675                 kvm_timer_blocking(vcpu);
 676
 677         /*
 678          * The kernel may decide to run userspace after calling vcpu_put, so
 679          * we reset cntvoff to 0 to ensure a consistent read between user
 680          * accesses to the virtual counter and kernel access to the physical
 681          * counter of non-VHE case. For VHE, the virtual counter uses a fixed
 682          * virtual offset of zero, so no need to zero CNTVOFF_EL2 register.
 683          */
 684         set_cntvoff(0);
 685 }
 686
 687 /*
 688  * With a userspace irqchip we have to check if the guest de-asserted the
 689  * timer and if so, unmask the timer irq signal on the host interrupt
 690  * controller to ensure that we see future timer signals.
 691  */
 692 static void unmask_vtimer_irq_user(struct kvm_vcpu *vcpu)
 693 {
 694         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 695
 696         if (!kvm_timer_should_fire(vtimer)) {
 697                 kvm_timer_update_irq(vcpu, false, vtimer);
 698                 if (static_branch_likely(&has_gic_active_state))
 699                         set_timer_irq_phys_active(vtimer, false);
 700                 else
 701                         enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
 702         }
 703 }
 704
 705 void kvm_timer_sync_user(struct kvm_vcpu *vcpu)
 706 {
 707         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 708
 709         if (unlikely(!timer->enabled))
 710                 return;
 711
 712         if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
 713                 unmask_vtimer_irq_user(vcpu);
 714 }
 715
 716 int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
 717 {
 718         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 719         struct timer_map map;
 720
 721         get_timer_map(vcpu, &map);
 722
 723         /*
 724          * The bits in CNTV_CTL are architecturally reset to UNKNOWN for ARMv8
 725          * and to 0 for ARMv7.  We provide an implementation that always
 726          * resets the timer to be disabled and unmasked and is compliant with
 727          * the ARMv7 architecture.
 728          */
 729         timer_set_ctl(vcpu_vtimer(vcpu), 0);
 730         timer_set_ctl(vcpu_ptimer(vcpu), 0);
 731
 732         if (timer->enabled) {
 733                 kvm_timer_update_irq(vcpu, false, vcpu_vtimer(vcpu));
 734                 kvm_timer_update_irq(vcpu, false, vcpu_ptimer(vcpu));
 735
 736                 if (irqchip_in_kernel(vcpu->kvm)) {
 737                         kvm_vgic_reset_mapped_irq(vcpu, map.direct_vtimer->irq.irq);
 738                         if (map.direct_ptimer)
 739                                 kvm_vgic_reset_mapped_irq(vcpu, map.direct_ptimer->irq.irq);
 740                 }
 741         }
 742
 743         if (map.emul_ptimer)
 744                 soft_timer_cancel(&map.emul_ptimer->hrtimer);
 745
 746         return 0;
 747 }
 748
 749 /* Make the updates of cntvoff for all vtimer contexts atomic */
 750 static void update_vtimer_cntvoff(struct kvm_vcpu *vcpu, u64 cntvoff)
 751 {
 752         int i;
 753         struct kvm *kvm = vcpu->kvm;
 754         struct kvm_vcpu *tmp;
 755
 756         mutex_lock(&kvm->lock);
 757         kvm_for_each_vcpu(i, tmp, kvm)
 758                 timer_set_offset(vcpu_vtimer(tmp), cntvoff);
 759
 760         /*
 761          * When called from the vcpu create path, the CPU being created is not
 762          * included in the loop above, so we just set it here as well.
 763          */
 764         timer_set_offset(vcpu_vtimer(vcpu), cntvoff);
 765         mutex_unlock(&kvm->lock);
 766 }
 767
 768 void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
 769 {
 770         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
 771         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 772         struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
 773
 774         vtimer->vcpu = vcpu;
 775         ptimer->vcpu = vcpu;
 776
 777         /* Synchronize cntvoff across all vtimers of a VM. */
 778         update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
 779         timer_set_offset(ptimer, 0);
 780
 781         hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 782         timer->bg_timer.function = kvm_bg_timer_expire;
 783
 784         hrtimer_init(&vtimer->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 785         hrtimer_init(&ptimer->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 786         vtimer->hrtimer.function = kvm_hrtimer_expire;
 787         ptimer->hrtimer.function = kvm_hrtimer_expire;
 788
 789         vtimer->irq.irq = default_vtimer_irq.irq;
 790         ptimer->irq.irq = default_ptimer_irq.irq;
 791
 792         vtimer->host_timer_irq = host_vtimer_irq;
 793         ptimer->host_timer_irq = host_ptimer_irq;
 794
 795         vtimer->host_timer_irq_flags = host_vtimer_irq_flags;
 796         ptimer->host_timer_irq_flags = host_ptimer_irq_flags;
 797 }
 798
 799 static void kvm_timer_init_interrupt(void *info)
 800 {
 801         enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
 802         enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
 803 }
 804
 805 int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
 806 {
 807         struct arch_timer_context *timer;
 808
 809         switch (regid) {
 810         case KVM_REG_ARM_TIMER_CTL:
 811                 timer = vcpu_vtimer(vcpu);
 812                 kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
 813                 break;
 814         case KVM_REG_ARM_TIMER_CNT:
 815                 timer = vcpu_vtimer(vcpu);
 816                 update_vtimer_cntvoff(vcpu, kvm_phys_timer_read() - value);
 817                 break;
 818         case KVM_REG_ARM_TIMER_CVAL:
 819                 timer = vcpu_vtimer(vcpu);
 820                 kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
 821                 break;
 822         case KVM_REG_ARM_PTIMER_CTL:
 823                 timer = vcpu_ptimer(vcpu);
 824                 kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
 825                 break;
 826         case KVM_REG_ARM_PTIMER_CVAL:
 827                 timer = vcpu_ptimer(vcpu);
 828                 kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
 829                 break;
 830
 831         default:
 832                 return -1;
 833         }
 834
 835         return 0;
 836 }
 837
 838 static u64 read_timer_ctl(struct arch_timer_context *timer)
 839 {
 840         /*
 841          * Set ISTATUS bit if it's expired.
 842          * Note that according to ARMv8 ARM Issue A.k, ISTATUS bit is
 843          * UNKNOWN when ENABLE bit is 0, so we chose to set ISTATUS bit
 844          * regardless of ENABLE bit for our implementation convenience.
 845          */
 846         u32 ctl = timer_get_ctl(timer);
 847
 848         if (!kvm_timer_compute_delta(timer))
 849                 ctl |= ARCH_TIMER_CTRL_IT_STAT;
 850
 851         return ctl;
 852 }
 853
 854 u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid)
 855 {
 856         switch (regid) {
 857         case KVM_REG_ARM_TIMER_CTL:
 858                 return kvm_arm_timer_read(vcpu,
 859                                           vcpu_vtimer(vcpu), TIMER_REG_CTL);
 860         case KVM_REG_ARM_TIMER_CNT:
 861                 return kvm_arm_timer_read(vcpu,
 862                                           vcpu_vtimer(vcpu), TIMER_REG_CNT);
 863         case KVM_REG_ARM_TIMER_CVAL:
 864                 return kvm_arm_timer_read(vcpu,
 865                                           vcpu_vtimer(vcpu), TIMER_REG_CVAL);
 866         case KVM_REG_ARM_PTIMER_CTL:
 867                 return kvm_arm_timer_read(vcpu,
 868                                           vcpu_ptimer(vcpu), TIMER_REG_CTL);
 869         case KVM_REG_ARM_PTIMER_CNT:
 870                 return kvm_arm_timer_read(vcpu,
 871                                           vcpu_ptimer(vcpu), TIMER_REG_CNT);
 872         case KVM_REG_ARM_PTIMER_CVAL:
 873                 return kvm_arm_timer_read(vcpu,
 874                                           vcpu_ptimer(vcpu), TIMER_REG_CVAL);
 875         }
 876         return (u64)-1;
 877 }
 878
 879 static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
 880                               struct arch_timer_context *timer,
 881                               enum kvm_arch_timer_regs treg)
 882 {
 883         u64 val;
 884
 885         switch (treg) {
 886         case TIMER_REG_TVAL:
 887                 val = timer_get_cval(timer) - kvm_phys_timer_read() + timer_get_offset(timer);
 888                 val = lower_32_bits(val);
 889                 break;
 890
 891         case TIMER_REG_CTL:
 892                 val = read_timer_ctl(timer);
 893                 break;
 894
 895         case TIMER_REG_CVAL:
 896                 val = timer_get_cval(timer);
 897                 break;
 898
 899         case TIMER_REG_CNT:
 900                 val = kvm_phys_timer_read() - timer_get_offset(timer);
 901                 break;
 902
 903         default:
 904                 BUG();
 905         }
 906
 907         return val;
 908 }
 909
 910 u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
 911                               enum kvm_arch_timers tmr,
 912                               enum kvm_arch_timer_regs treg)
 913 {
 914         u64 val;
 915
 916         preempt_disable();
 917         kvm_timer_vcpu_put(vcpu);
 918
 919         val = kvm_arm_timer_read(vcpu, vcpu_get_timer(vcpu, tmr), treg);
 920
 921         kvm_timer_vcpu_load(vcpu);
 922         preempt_enable();
 923
 924         return val;
 925 }
 926
 927 static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
 928                                 struct arch_timer_context *timer,
 929                                 enum kvm_arch_timer_regs treg,
 930                                 u64 val)
 931 {
 932         switch (treg) {
 933         case TIMER_REG_TVAL:
 934                 timer_set_cval(timer, kvm_phys_timer_read() - timer_get_offset(timer) + (s32)val);
 935                 break;
 936
 937         case TIMER_REG_CTL:
 938                 timer_set_ctl(timer, val & ~ARCH_TIMER_CTRL_IT_STAT);
 939                 break;
 940
 941         case TIMER_REG_CVAL:
 942                 timer_set_cval(timer, val);
 943                 break;
 944
 945         default:
 946                 BUG();
 947         }
 948 }
 949
 950 void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu,
 951                                 enum kvm_arch_timers tmr,
 952                                 enum kvm_arch_timer_regs treg,
 953                                 u64 val)
 954 {
 955         preempt_disable();
 956         kvm_timer_vcpu_put(vcpu);
 957
 958         kvm_arm_timer_write(vcpu, vcpu_get_timer(vcpu, tmr), treg, val);
 959
 960         kvm_timer_vcpu_load(vcpu);
 961         preempt_enable();
 962 }
 963
 964 static int kvm_timer_starting_cpu(unsigned int cpu)
 965 {
 966         kvm_timer_init_interrupt(NULL);
 967         return 0;
 968 }
 969
 970 static int kvm_timer_dying_cpu(unsigned int cpu)
 971 {
 972         disable_percpu_irq(host_vtimer_irq);
 973         return 0;
 974 }
 975
 976 int kvm_timer_hyp_init(bool has_gic)
 977 {
 978         struct arch_timer_kvm_info *info;
 979         int err;
 980
 981         info = arch_timer_get_kvm_info();
 982         timecounter = &info->timecounter;
 983
 984         if (!timecounter->cc) {
 985                 kvm_err("kvm_arch_timer: uninitialized timecounter\n");
 986                 return -ENODEV;
 987         }
 988
 989         /* First, do the virtual EL1 timer irq */
 990
 991         if (info->virtual_irq <= 0) {
 992                 kvm_err("kvm_arch_timer: invalid virtual timer IRQ: %d\n",
 993                         info->virtual_irq);
 994                 return -ENODEV;
 995         }
 996         host_vtimer_irq = info->virtual_irq;
 997
 998         host_vtimer_irq_flags = irq_get_trigger_type(host_vtimer_irq);
 999         if (host_vtimer_irq_flags != IRQF_TRIGGER_HIGH &&
1000             host_vtimer_irq_flags != IRQF_TRIGGER_LOW) {
1001                 kvm_err("Invalid trigger for vtimer IRQ%d, assuming level low\n",
1002                         host_vtimer_irq);
1003                 host_vtimer_irq_flags = IRQF_TRIGGER_LOW;
1004         }
1005
1006         err = request_percpu_irq(host_vtimer_irq, kvm_arch_timer_handler,
1007                                  "kvm guest vtimer", kvm_get_running_vcpus());
1008         if (err) {
1009                 kvm_err("kvm_arch_timer: can't request vtimer interrupt %d (%d)\n",
1010                         host_vtimer_irq, err);
1011                 return err;
1012         }
1013
1014         if (has_gic) {
1015                 err = irq_set_vcpu_affinity(host_vtimer_irq,
1016                                             kvm_get_running_vcpus());
1017                 if (err) {
1018                         kvm_err("kvm_arch_timer: error setting vcpu affinity\n");
1019                         goto out_free_irq;
1020                 }
1021
1022                 static_branch_enable(&has_gic_active_state);
1023         }
1024
1025         kvm_debug("virtual timer IRQ%d\n", host_vtimer_irq);
1026
1027         /* Now let's do the physical EL1 timer irq */
1028
1029         if (info->physical_irq > 0) {
1030                 host_ptimer_irq = info->physical_irq;
1031                 host_ptimer_irq_flags = irq_get_trigger_type(host_ptimer_irq);
1032                 if (host_ptimer_irq_flags != IRQF_TRIGGER_HIGH &&
1033                     host_ptimer_irq_flags != IRQF_TRIGGER_LOW) {
1034                         kvm_err("Invalid trigger for ptimer IRQ%d, assuming level low\n",
1035                                 host_ptimer_irq);
1036                         host_ptimer_irq_flags = IRQF_TRIGGER_LOW;
1037                 }
1038
1039                 err = request_percpu_irq(host_ptimer_irq, kvm_arch_timer_handler,
1040                                          "kvm guest ptimer", kvm_get_running_vcpus());
1041                 if (err) {
1042                         kvm_err("kvm_arch_timer: can't request ptimer interrupt %d (%d)\n",
1043                                 host_ptimer_irq, err);
1044                         return err;
1045                 }
1046
1047                 if (has_gic) {
1048                         err = irq_set_vcpu_affinity(host_ptimer_irq,
1049                                                     kvm_get_running_vcpus());
1050                         if (err) {
1051                                 kvm_err("kvm_arch_timer: error setting vcpu affinity\n");
1052                                 goto out_free_irq;
1053                         }
1054                 }
1055
1056                 kvm_debug("physical timer IRQ%d\n", host_ptimer_irq);
1057         } else if (has_vhe()) {
1058                 kvm_err("kvm_arch_timer: invalid physical timer IRQ: %d\n",
1059                         info->physical_irq);
1060                 err = -ENODEV;
1061                 goto out_free_irq;
1062         }
1063
1064         cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING,
1065                           "kvm/arm/timer:starting", kvm_timer_starting_cpu,
1066                           kvm_timer_dying_cpu);
1067         return 0;
1068 out_free_irq:
1069         free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus());
1070         return err;
1071 }
1072
1073 void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
1074 {
1075         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
1076
1077         soft_timer_cancel(&timer->bg_timer);
1078 }
1079
1080 static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
1081 {
1082         int vtimer_irq, ptimer_irq;
1083         int i, ret;
1084
1085         vtimer_irq = vcpu_vtimer(vcpu)->irq.irq;
1086         ret = kvm_vgic_set_owner(vcpu, vtimer_irq, vcpu_vtimer(vcpu));
1087         if (ret)
1088                 return false;
1089
1090         ptimer_irq = vcpu_ptimer(vcpu)->irq.irq;
1091         ret = kvm_vgic_set_owner(vcpu, ptimer_irq, vcpu_ptimer(vcpu));
1092         if (ret)
1093                 return false;
1094
1095         kvm_for_each_vcpu(i, vcpu, vcpu->kvm) {
1096                 if (vcpu_vtimer(vcpu)->irq.irq != vtimer_irq ||
1097                     vcpu_ptimer(vcpu)->irq.irq != ptimer_irq)
1098                         return false;
1099         }
1100
1101         return true;
1102 }
1103
1104 bool kvm_arch_timer_get_input_level(int vintid)
1105 {
1106         struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
1107         struct arch_timer_context *timer;
1108
1109         if (vintid == vcpu_vtimer(vcpu)->irq.irq)
1110                 timer = vcpu_vtimer(vcpu);
1111         else if (vintid == vcpu_ptimer(vcpu)->irq.irq)
1112                 timer = vcpu_ptimer(vcpu);
1113         else
1114                 BUG();
1115
1116         return kvm_timer_should_fire(timer);
1117 }
1118
1119 int kvm_timer_enable(struct kvm_vcpu *vcpu)
1120 {
1121         struct arch_timer_cpu *timer = vcpu_timer(vcpu);
1122         struct timer_map map;
1123         int ret;
1124
1125         if (timer->enabled)
1126                 return 0;
1127
1128         /* Without a VGIC we do not map virtual IRQs to physical IRQs */
1129         if (!irqchip_in_kernel(vcpu->kvm))
1130                 goto no_vgic;
1131
1132         if (!vgic_initialized(vcpu->kvm))
1133                 return -ENODEV;
1134
1135         if (!timer_irqs_are_valid(vcpu)) {
1136                 kvm_debug("incorrectly configured timer irqs\n");
1137                 return -EINVAL;
1138         }
1139
1140         get_timer_map(vcpu, &map);
1141
1142         ret = kvm_vgic_map_phys_irq(vcpu,
1143                                     map.direct_vtimer->host_timer_irq,
1144                                     map.direct_vtimer->irq.irq,
1145                                     kvm_arch_timer_get_input_level);
1146         if (ret)
1147                 return ret;
1148
1149         if (map.direct_ptimer) {
1150                 ret = kvm_vgic_map_phys_irq(vcpu,
1151                                             map.direct_ptimer->host_timer_irq,
1152                                             map.direct_ptimer->irq.irq,
1153                                             kvm_arch_timer_get_input_level);
1154         }
1155
1156         if (ret)
1157                 return ret;
1158
1159 no_vgic:
1160         timer->enabled = 1;
1161         return 0;
1162 }
1163
1164 /*
1165  * On VHE system, we only need to configure the EL2 timer trap register once,
1166  * not for every world switch.
1167  * The host kernel runs at EL2 with HCR_EL2.TGE == 1,
1168  * and this makes those bits have no effect for the host kernel execution.
1169  */
1170 void kvm_timer_init_vhe(void)
1171 {
1172         /* When HCR_EL2.E2H ==1, EL1PCEN and EL1PCTEN are shifted by 10 */
1173         u32 cnthctl_shift = 10;
1174         u64 val;
1175
1176         /*
1177          * VHE systems allow the guest direct access to the EL1 physical
1178          * timer/counter.
1179          */
1180         val = read_sysreg(cnthctl_el2);
1181         val |= (CNTHCTL_EL1PCEN << cnthctl_shift);
1182         val |= (CNTHCTL_EL1PCTEN << cnthctl_shift);
1183         write_sysreg(val, cnthctl_el2);
1184 }
1185
1186 static void set_timer_irqs(struct kvm *kvm, int vtimer_irq, int ptimer_irq)
1187 {
1188         struct kvm_vcpu *vcpu;
1189         int i;
1190
1191         kvm_for_each_vcpu(i, vcpu, kvm) {
1192                 vcpu_vtimer(vcpu)->irq.irq = vtimer_irq;
1193                 vcpu_ptimer(vcpu)->irq.irq = ptimer_irq;
1194         }
1195 }
1196
1197 int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
1198 {
1199         int __user *uaddr = (int __user *)(long)attr->addr;
1200         struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
1201         struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
1202         int irq;
1203
1204         if (!irqchip_in_kernel(vcpu->kvm))
1205                 return -EINVAL;
1206
1207         if (get_user(irq, uaddr))
1208                 return -EFAULT;
1209
1210         if (!(irq_is_ppi(irq)))
1211                 return -EINVAL;
1212
1213         if (vcpu->arch.timer_cpu.enabled)
1214                 return -EBUSY;
1215
1216         switch (attr->attr) {
1217         case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
1218                 set_timer_irqs(vcpu->kvm, irq, ptimer->irq.irq);
1219                 break;
1220         case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
1221                 set_timer_irqs(vcpu->kvm, vtimer->irq.irq, irq);
1222                 break;
1223         default:
1224                 return -ENXIO;
1225         }
1226
1227         return 0;
1228 }
1229
1230 int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
1231 {
1232         int __user *uaddr = (int __user *)(long)attr->addr;
1233         struct arch_timer_context *timer;
1234         int irq;
1235
1236         switch (attr->attr) {
1237         case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
1238                 timer = vcpu_vtimer(vcpu);
1239                 break;
1240         case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
1241                 timer = vcpu_ptimer(vcpu);
1242                 break;
1243         default:
1244                 return -ENXIO;
1245         }
1246
1247         irq = timer->irq.irq;
1248         return put_user(irq, uaddr);
1249 }
1250
1251 int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
1252 {
1253         switch (attr->attr) {
1254         case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
1255         case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
1256                 return 0;
1257         }
1258
1259         return -ENXIO;
1260 }