17837699fSSheng Yang /* 27837699fSSheng Yang * 8253/8254 interval timer emulation 37837699fSSheng Yang * 47837699fSSheng Yang * Copyright (c) 2003-2004 Fabrice Bellard 57837699fSSheng Yang * Copyright (c) 2006 Intel Corporation 67837699fSSheng Yang * Copyright (c) 2007 Keir Fraser, XenSource Inc 77837699fSSheng Yang * Copyright (c) 2008 Intel Corporation 89611c187SNicolas Kaiser * Copyright 2009 Red Hat, Inc. and/or its affiliates. 97837699fSSheng Yang * 107837699fSSheng Yang * Permission is hereby granted, free of charge, to any person obtaining a copy 117837699fSSheng Yang * of this software and associated documentation files (the "Software"), to deal 127837699fSSheng Yang * in the Software without restriction, including without limitation the rights 137837699fSSheng Yang * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 147837699fSSheng Yang * copies of the Software, and to permit persons to whom the Software is 157837699fSSheng Yang * furnished to do so, subject to the following conditions: 167837699fSSheng Yang * 177837699fSSheng Yang * The above copyright notice and this permission notice shall be included in 187837699fSSheng Yang * all copies or substantial portions of the Software. 197837699fSSheng Yang * 207837699fSSheng Yang * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 217837699fSSheng Yang * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 227837699fSSheng Yang * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 237837699fSSheng Yang * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 247837699fSSheng Yang * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 257837699fSSheng Yang * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 267837699fSSheng Yang * THE SOFTWARE. 277837699fSSheng Yang * 287837699fSSheng Yang * Authors: 297837699fSSheng Yang * Sheng Yang <sheng.yang@intel.com> 307837699fSSheng Yang * Based on QEMU and Xen. 317837699fSSheng Yang */ 327837699fSSheng Yang 33a78d9626SJoe Perches #define pr_fmt(fmt) "pit: " fmt 34a78d9626SJoe Perches 357837699fSSheng Yang #include <linux/kvm_host.h> 365a0e3ad6STejun Heo #include <linux/slab.h> 377837699fSSheng Yang 3849df6397SSteve Rutherford #include "ioapic.h" 397837699fSSheng Yang #include "irq.h" 407837699fSSheng Yang #include "i8254.h" 419ed96e87SMarcelo Tosatti #include "x86.h" 427837699fSSheng Yang 437837699fSSheng Yang #ifndef CONFIG_X86_64 446f6d6a1aSRoman Zippel #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) 457837699fSSheng Yang #else 467837699fSSheng Yang #define mod_64(x, y) ((x) % (y)) 477837699fSSheng Yang #endif 487837699fSSheng Yang 497837699fSSheng Yang #define RW_STATE_LSB 1 507837699fSSheng Yang #define RW_STATE_MSB 2 517837699fSSheng Yang #define RW_STATE_WORD0 3 527837699fSSheng Yang #define RW_STATE_WORD1 4 537837699fSSheng Yang 5409edea72SRadim Krčmář static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val) 557837699fSSheng Yang { 5609edea72SRadim Krčmář struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 577837699fSSheng Yang 587837699fSSheng Yang switch (c->mode) { 597837699fSSheng Yang default: 607837699fSSheng Yang case 0: 617837699fSSheng Yang case 4: 627837699fSSheng Yang /* XXX: just disable/enable counting */ 637837699fSSheng Yang break; 647837699fSSheng Yang case 1: 657837699fSSheng Yang case 2: 667837699fSSheng Yang case 3: 677837699fSSheng Yang case 5: 687837699fSSheng Yang /* Restart counting on rising edge. */ 697837699fSSheng Yang if (c->gate < val) 707837699fSSheng Yang c->count_load_time = ktime_get(); 717837699fSSheng Yang break; 727837699fSSheng Yang } 737837699fSSheng Yang 747837699fSSheng Yang c->gate = val; 757837699fSSheng Yang } 767837699fSSheng Yang 7709edea72SRadim Krčmář static int pit_get_gate(struct kvm_pit *pit, int channel) 787837699fSSheng Yang { 7909edea72SRadim Krčmář return pit->pit_state.channels[channel].gate; 807837699fSSheng Yang } 817837699fSSheng Yang 8209edea72SRadim Krčmář static s64 __kpit_elapsed(struct kvm_pit *pit) 83fd668423SMarcelo Tosatti { 84fd668423SMarcelo Tosatti s64 elapsed; 85fd668423SMarcelo Tosatti ktime_t remaining; 8609edea72SRadim Krčmář struct kvm_kpit_state *ps = &pit->pit_state; 87fd668423SMarcelo Tosatti 8826ef1924SAvi Kivity if (!ps->period) 890ff77873SMarcelo Tosatti return 0; 900ff77873SMarcelo Tosatti 91ede2ccc5SMarcelo Tosatti /* 92ede2ccc5SMarcelo Tosatti * The Counter does not stop when it reaches zero. In 93ede2ccc5SMarcelo Tosatti * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to 94ede2ccc5SMarcelo Tosatti * the highest count, either FFFF hex for binary counting 95ede2ccc5SMarcelo Tosatti * or 9999 for BCD counting, and continues counting. 96ede2ccc5SMarcelo Tosatti * Modes 2 and 3 are periodic; the Counter reloads 97ede2ccc5SMarcelo Tosatti * itself with the initial count and continues counting 98ede2ccc5SMarcelo Tosatti * from there. 99ede2ccc5SMarcelo Tosatti */ 10026ef1924SAvi Kivity remaining = hrtimer_get_remaining(&ps->timer); 10126ef1924SAvi Kivity elapsed = ps->period - ktime_to_ns(remaining); 102fd668423SMarcelo Tosatti 103fd668423SMarcelo Tosatti return elapsed; 104fd668423SMarcelo Tosatti } 105fd668423SMarcelo Tosatti 10609edea72SRadim Krčmář static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c, 107fd668423SMarcelo Tosatti int channel) 108fd668423SMarcelo Tosatti { 109fd668423SMarcelo Tosatti if (channel == 0) 11009edea72SRadim Krčmář return __kpit_elapsed(pit); 111fd668423SMarcelo Tosatti 112fd668423SMarcelo Tosatti return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); 113fd668423SMarcelo Tosatti } 114fd668423SMarcelo Tosatti 11509edea72SRadim Krčmář static int pit_get_count(struct kvm_pit *pit, int channel) 1167837699fSSheng Yang { 11709edea72SRadim Krčmář struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 1187837699fSSheng Yang s64 d, t; 1197837699fSSheng Yang int counter; 1207837699fSSheng Yang 12109edea72SRadim Krčmář t = kpit_elapsed(pit, c, channel); 1220e4d4415SPaolo Bonzini d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC); 1237837699fSSheng Yang 1247837699fSSheng Yang switch (c->mode) { 1257837699fSSheng Yang case 0: 1267837699fSSheng Yang case 1: 1277837699fSSheng Yang case 4: 1287837699fSSheng Yang case 5: 1297837699fSSheng Yang counter = (c->count - d) & 0xffff; 1307837699fSSheng Yang break; 1317837699fSSheng Yang case 3: 1327837699fSSheng Yang /* XXX: may be incorrect for odd counts */ 1337837699fSSheng Yang counter = c->count - (mod_64((2 * d), c->count)); 1347837699fSSheng Yang break; 1357837699fSSheng Yang default: 1367837699fSSheng Yang counter = c->count - mod_64(d, c->count); 1377837699fSSheng Yang break; 1387837699fSSheng Yang } 1397837699fSSheng Yang return counter; 1407837699fSSheng Yang } 1417837699fSSheng Yang 14209edea72SRadim Krčmář static int pit_get_out(struct kvm_pit *pit, int channel) 1437837699fSSheng Yang { 14409edea72SRadim Krčmář struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 1457837699fSSheng Yang s64 d, t; 1467837699fSSheng Yang int out; 1477837699fSSheng Yang 14809edea72SRadim Krčmář t = kpit_elapsed(pit, c, channel); 1490e4d4415SPaolo Bonzini d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC); 1507837699fSSheng Yang 1517837699fSSheng Yang switch (c->mode) { 1527837699fSSheng Yang default: 1537837699fSSheng Yang case 0: 1547837699fSSheng Yang out = (d >= c->count); 1557837699fSSheng Yang break; 1567837699fSSheng Yang case 1: 1577837699fSSheng Yang out = (d < c->count); 1587837699fSSheng Yang break; 1597837699fSSheng Yang case 2: 1607837699fSSheng Yang out = ((mod_64(d, c->count) == 0) && (d != 0)); 1617837699fSSheng Yang break; 1627837699fSSheng Yang case 3: 1637837699fSSheng Yang out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); 1647837699fSSheng Yang break; 1657837699fSSheng Yang case 4: 1667837699fSSheng Yang case 5: 1677837699fSSheng Yang out = (d == c->count); 1687837699fSSheng Yang break; 1697837699fSSheng Yang } 1707837699fSSheng Yang 1717837699fSSheng Yang return out; 1727837699fSSheng Yang } 1737837699fSSheng Yang 17409edea72SRadim Krčmář static void pit_latch_count(struct kvm_pit *pit, int channel) 1757837699fSSheng Yang { 17609edea72SRadim Krčmář struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 1777837699fSSheng Yang 1787837699fSSheng Yang if (!c->count_latched) { 17909edea72SRadim Krčmář c->latched_count = pit_get_count(pit, channel); 1807837699fSSheng Yang c->count_latched = c->rw_mode; 1817837699fSSheng Yang } 1827837699fSSheng Yang } 1837837699fSSheng Yang 18409edea72SRadim Krčmář static void pit_latch_status(struct kvm_pit *pit, int channel) 1857837699fSSheng Yang { 18609edea72SRadim Krčmář struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 1877837699fSSheng Yang 1887837699fSSheng Yang if (!c->status_latched) { 1897837699fSSheng Yang /* TODO: Return NULL COUNT (bit 6). */ 19009edea72SRadim Krčmář c->status = ((pit_get_out(pit, channel) << 7) | 1917837699fSSheng Yang (c->rw_mode << 4) | 1927837699fSSheng Yang (c->mode << 1) | 1937837699fSSheng Yang c->bcd); 1947837699fSSheng Yang c->status_latched = 1; 1957837699fSSheng Yang } 1967837699fSSheng Yang } 1977837699fSSheng Yang 198a3e13115SRadim Krčmář static inline struct kvm_pit *pit_state_to_pit(struct kvm_kpit_state *ps) 199a3e13115SRadim Krčmář { 200a3e13115SRadim Krčmář return container_of(ps, struct kvm_pit, pit_state); 201a3e13115SRadim Krčmář } 202a3e13115SRadim Krčmář 203ee032c99SHarvey Harrison static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 2043cf57fedSMarcelo Tosatti { 2053cf57fedSMarcelo Tosatti struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, 2063cf57fedSMarcelo Tosatti irq_ack_notifier); 207a3e13115SRadim Krčmář struct kvm_pit *pit = pit_state_to_pit(ps); 20833572ac0SChris Lalancette 209ddf54503SRadim Krčmář atomic_set(&ps->irq_ack, 1); 210ddf54503SRadim Krčmář /* irq_ack should be set before pending is read. Order accesses with 211ddf54503SRadim Krčmář * inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work. 212ddf54503SRadim Krčmář */ 213ddf54503SRadim Krčmář smp_mb(); 21471474e2fSRadim Krčmář if (atomic_dec_if_positive(&ps->pending) > 0) 21536da91bdSPetr Mladek kthread_queue_work(pit->worker, &pit->expired); 2163cf57fedSMarcelo Tosatti } 2173cf57fedSMarcelo Tosatti 2182f599714SMarcelo Tosatti void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 2192f599714SMarcelo Tosatti { 2202f599714SMarcelo Tosatti struct kvm_pit *pit = vcpu->kvm->arch.vpit; 2212f599714SMarcelo Tosatti struct hrtimer *timer; 2222f599714SMarcelo Tosatti 2230214f6bbSSean Christopherson /* Somewhat arbitrarily make vcpu0 the owner of the PIT. */ 2240214f6bbSSean Christopherson if (vcpu->vcpu_id || !pit) 2252f599714SMarcelo Tosatti return; 2262f599714SMarcelo Tosatti 22726ef1924SAvi Kivity timer = &pit->pit_state.timer; 2282febc839SAndy Honig mutex_lock(&pit->pit_state.lock); 2292f599714SMarcelo Tosatti if (hrtimer_cancel(timer)) 230beb20d52SArjan van de Ven hrtimer_start_expires(timer, HRTIMER_MODE_ABS); 2312febc839SAndy Honig mutex_unlock(&pit->pit_state.lock); 2322f599714SMarcelo Tosatti } 2332f599714SMarcelo Tosatti 23433572ac0SChris Lalancette static void destroy_pit_timer(struct kvm_pit *pit) 2357837699fSSheng Yang { 23626ef1924SAvi Kivity hrtimer_cancel(&pit->pit_state.timer); 2373989144fSPetr Mladek kthread_flush_work(&pit->expired); 2387837699fSSheng Yang } 2397837699fSSheng Yang 240b6ddf05fSJan Kiszka static void pit_do_work(struct kthread_work *work) 24133572ac0SChris Lalancette { 24233572ac0SChris Lalancette struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); 24333572ac0SChris Lalancette struct kvm *kvm = pit->kvm; 24433572ac0SChris Lalancette struct kvm_vcpu *vcpu; 24546808a4cSMarc Zyngier unsigned long i; 24633572ac0SChris Lalancette struct kvm_kpit_state *ps = &pit->pit_state; 24733572ac0SChris Lalancette 248a0aace5aSRadim Krčmář if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0)) 249ddf54503SRadim Krčmář return; 250ddf54503SRadim Krčmář 2514a2095dfSRadim Krčmář kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false); 2524a2095dfSRadim Krčmář kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false); 25333572ac0SChris Lalancette 25433572ac0SChris Lalancette /* 25533572ac0SChris Lalancette * Provides NMI watchdog support via Virtual Wire mode. 256ddf54503SRadim Krčmář * The route is: PIT -> LVT0 in NMI mode. 25733572ac0SChris Lalancette * 258ddf54503SRadim Krčmář * Note: Our Virtual Wire implementation does not follow 259ddf54503SRadim Krčmář * the MP specification. We propagate a PIT interrupt to all 260ddf54503SRadim Krčmář * VCPUs and only when LVT0 is in NMI mode. The interrupt can 261ddf54503SRadim Krčmář * also be simultaneously delivered through PIC and IOAPIC. 26233572ac0SChris Lalancette */ 26342720138SRadim Krčmář if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0) 26433572ac0SChris Lalancette kvm_for_each_vcpu(i, vcpu, kvm) 26533572ac0SChris Lalancette kvm_apic_nmi_wd_deliver(vcpu); 26633572ac0SChris Lalancette } 26733572ac0SChris Lalancette 26833572ac0SChris Lalancette static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 26933572ac0SChris Lalancette { 27026ef1924SAvi Kivity struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer); 271a3e13115SRadim Krčmář struct kvm_pit *pt = pit_state_to_pit(ps); 27233572ac0SChris Lalancette 273a0aace5aSRadim Krčmář if (atomic_read(&ps->reinject)) 27426ef1924SAvi Kivity atomic_inc(&ps->pending); 2757dd0fdffSRadim Krčmář 27636da91bdSPetr Mladek kthread_queue_work(pt->worker, &pt->expired); 27733572ac0SChris Lalancette 27826ef1924SAvi Kivity if (ps->is_periodic) { 27926ef1924SAvi Kivity hrtimer_add_expires_ns(&ps->timer, ps->period); 28033572ac0SChris Lalancette return HRTIMER_RESTART; 28133572ac0SChris Lalancette } else 28233572ac0SChris Lalancette return HRTIMER_NORESTART; 28333572ac0SChris Lalancette } 28433572ac0SChris Lalancette 285fd700a00SRadim Krčmář static inline void kvm_pit_reset_reinject(struct kvm_pit *pit) 286fd700a00SRadim Krčmář { 287fd700a00SRadim Krčmář atomic_set(&pit->pit_state.pending, 0); 288ddf54503SRadim Krčmář atomic_set(&pit->pit_state.irq_ack, 1); 289fd700a00SRadim Krčmář } 290fd700a00SRadim Krčmář 29171474e2fSRadim Krčmář void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject) 29271474e2fSRadim Krčmář { 29371474e2fSRadim Krčmář struct kvm_kpit_state *ps = &pit->pit_state; 29471474e2fSRadim Krčmář struct kvm *kvm = pit->kvm; 29571474e2fSRadim Krčmář 296a0aace5aSRadim Krčmář if (atomic_read(&ps->reinject) == reinject) 29771474e2fSRadim Krčmář return; 29871474e2fSRadim Krčmář 299e2ed4078SSuravee Suthikulpanit /* 300e2ed4078SSuravee Suthikulpanit * AMD SVM AVIC accelerates EOI write and does not trap. 301e2ed4078SSuravee Suthikulpanit * This cause in-kernel PIT re-inject mode to fail 302e2ed4078SSuravee Suthikulpanit * since it checks ps->irq_ack before kvm_set_irq() 303e2ed4078SSuravee Suthikulpanit * and relies on the ack notifier to timely queue 304e2ed4078SSuravee Suthikulpanit * the pt->worker work iterm and reinject the missed tick. 305e2ed4078SSuravee Suthikulpanit * So, deactivate APICv when PIT is in reinject mode. 306e2ed4078SSuravee Suthikulpanit */ 30771474e2fSRadim Krčmář if (reinject) { 308320af55aSSean Christopherson kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PIT_REINJ); 30971474e2fSRadim Krčmář /* The initial state is preserved while ps->reinject == 0. */ 31071474e2fSRadim Krčmář kvm_pit_reset_reinject(pit); 31171474e2fSRadim Krčmář kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 31271474e2fSRadim Krčmář kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 31371474e2fSRadim Krčmář } else { 314320af55aSSean Christopherson kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PIT_REINJ); 31571474e2fSRadim Krčmář kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 31671474e2fSRadim Krčmář kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 31771474e2fSRadim Krčmář } 31871474e2fSRadim Krčmář 319a0aace5aSRadim Krčmář atomic_set(&ps->reinject, reinject); 32071474e2fSRadim Krčmář } 32171474e2fSRadim Krčmář 32209edea72SRadim Krčmář static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period) 3237837699fSSheng Yang { 32409edea72SRadim Krčmář struct kvm_kpit_state *ps = &pit->pit_state; 32509edea72SRadim Krčmář struct kvm *kvm = pit->kvm; 3267837699fSSheng Yang s64 interval; 3277837699fSSheng Yang 32849df6397SSteve Rutherford if (!ioapic_in_kernel(kvm) || 32949df6397SSteve Rutherford ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) 3300924ab2cSJan Kiszka return; 3310924ab2cSJan Kiszka 3320e4d4415SPaolo Bonzini interval = mul_u64_u32_div(val, NSEC_PER_SEC, KVM_PIT_FREQ); 3337837699fSSheng Yang 334a78d9626SJoe Perches pr_debug("create pit timer, interval is %llu nsec\n", interval); 3357837699fSSheng Yang 3367837699fSSheng Yang /* TODO The new value only affected after the retriggered */ 33726ef1924SAvi Kivity hrtimer_cancel(&ps->timer); 3383989144fSPetr Mladek kthread_flush_work(&pit->expired); 33926ef1924SAvi Kivity ps->period = interval; 340d3c7b77dSMarcelo Tosatti ps->is_periodic = is_period; 341d3c7b77dSMarcelo Tosatti 34209edea72SRadim Krčmář kvm_pit_reset_reinject(pit); 3437837699fSSheng Yang 3449ed96e87SMarcelo Tosatti /* 3459ed96e87SMarcelo Tosatti * Do not allow the guest to program periodic timers with small 3469ed96e87SMarcelo Tosatti * interval, since the hrtimers are not throttled by the host 3479ed96e87SMarcelo Tosatti * scheduler. 3489ed96e87SMarcelo Tosatti */ 3499ed96e87SMarcelo Tosatti if (ps->is_periodic) { 3509ed96e87SMarcelo Tosatti s64 min_period = min_timer_period_us * 1000LL; 3519ed96e87SMarcelo Tosatti 3529ed96e87SMarcelo Tosatti if (ps->period < min_period) { 3539ed96e87SMarcelo Tosatti pr_info_ratelimited( 3549ed96e87SMarcelo Tosatti "kvm: requested %lld ns " 3559ed96e87SMarcelo Tosatti "i8254 timer period limited to %lld ns\n", 3569ed96e87SMarcelo Tosatti ps->period, min_period); 3579ed96e87SMarcelo Tosatti ps->period = min_period; 3589ed96e87SMarcelo Tosatti } 3599ed96e87SMarcelo Tosatti } 3609ed96e87SMarcelo Tosatti 36126ef1924SAvi Kivity hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), 3627837699fSSheng Yang HRTIMER_MODE_ABS); 3637837699fSSheng Yang } 3647837699fSSheng Yang 36509edea72SRadim Krčmář static void pit_load_count(struct kvm_pit *pit, int channel, u32 val) 3667837699fSSheng Yang { 36709edea72SRadim Krčmář struct kvm_kpit_state *ps = &pit->pit_state; 3687837699fSSheng Yang 369e6302698SMiaohe Lin pr_debug("load_count val is %u, channel is %d\n", val, channel); 3707837699fSSheng Yang 3717837699fSSheng Yang /* 372ede2ccc5SMarcelo Tosatti * The largest possible initial count is 0; this is equivalent 373ede2ccc5SMarcelo Tosatti * to 216 for binary counting and 104 for BCD counting. 3747837699fSSheng Yang */ 3757837699fSSheng Yang if (val == 0) 3767837699fSSheng Yang val = 0x10000; 3777837699fSSheng Yang 3787837699fSSheng Yang ps->channels[channel].count = val; 3797837699fSSheng Yang 380fd668423SMarcelo Tosatti if (channel != 0) { 381fd668423SMarcelo Tosatti ps->channels[channel].count_load_time = ktime_get(); 3827837699fSSheng Yang return; 383fd668423SMarcelo Tosatti } 3847837699fSSheng Yang 3857837699fSSheng Yang /* Two types of timer 3867837699fSSheng Yang * mode 1 is one shot, mode 2 is period, otherwise del timer */ 3877837699fSSheng Yang switch (ps->channels[0].mode) { 388ede2ccc5SMarcelo Tosatti case 0: 3897837699fSSheng Yang case 1: 390ece15babSMarcelo Tosatti /* FIXME: enhance mode 4 precision */ 391ece15babSMarcelo Tosatti case 4: 39209edea72SRadim Krčmář create_pit_timer(pit, val, 0); 3937837699fSSheng Yang break; 3947837699fSSheng Yang case 2: 395f6975545SAurelien Jarno case 3: 39609edea72SRadim Krčmář create_pit_timer(pit, val, 1); 3977837699fSSheng Yang break; 3987837699fSSheng Yang default: 39909edea72SRadim Krčmář destroy_pit_timer(pit); 4007837699fSSheng Yang } 4017837699fSSheng Yang } 4027837699fSSheng Yang 40309edea72SRadim Krčmář void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val, 40409edea72SRadim Krčmář int hpet_legacy_start) 405e0f63cb9SSheng Yang { 406e9f42757SBeth Kon u8 saved_mode; 407b69d920fSRadim Krčmář 40809edea72SRadim Krčmář WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock)); 409b69d920fSRadim Krčmář 410e9f42757SBeth Kon if (hpet_legacy_start) { 411e9f42757SBeth Kon /* save existing mode for later reenablement */ 412e5e57e7aSPaolo Bonzini WARN_ON(channel != 0); 41309edea72SRadim Krčmář saved_mode = pit->pit_state.channels[0].mode; 41409edea72SRadim Krčmář pit->pit_state.channels[0].mode = 0xff; /* disable timer */ 41509edea72SRadim Krčmář pit_load_count(pit, channel, val); 41609edea72SRadim Krčmář pit->pit_state.channels[0].mode = saved_mode; 417e9f42757SBeth Kon } else { 41809edea72SRadim Krčmář pit_load_count(pit, channel, val); 419e9f42757SBeth Kon } 420e0f63cb9SSheng Yang } 421e0f63cb9SSheng Yang 422d76685c4SGregory Haskins static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev) 423d76685c4SGregory Haskins { 424d76685c4SGregory Haskins return container_of(dev, struct kvm_pit, dev); 425d76685c4SGregory Haskins } 426d76685c4SGregory Haskins 427d76685c4SGregory Haskins static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev) 428d76685c4SGregory Haskins { 429d76685c4SGregory Haskins return container_of(dev, struct kvm_pit, speaker_dev); 430d76685c4SGregory Haskins } 431d76685c4SGregory Haskins 432bda9020eSMichael S. Tsirkin static inline int pit_in_range(gpa_t addr) 433bda9020eSMichael S. Tsirkin { 434bda9020eSMichael S. Tsirkin return ((addr >= KVM_PIT_BASE_ADDRESS) && 435bda9020eSMichael S. Tsirkin (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH)); 436bda9020eSMichael S. Tsirkin } 437bda9020eSMichael S. Tsirkin 438e32edf4fSNikolay Nikolaev static int pit_ioport_write(struct kvm_vcpu *vcpu, 439e32edf4fSNikolay Nikolaev struct kvm_io_device *this, 4407837699fSSheng Yang gpa_t addr, int len, const void *data) 4417837699fSSheng Yang { 442d76685c4SGregory Haskins struct kvm_pit *pit = dev_to_pit(this); 4437837699fSSheng Yang struct kvm_kpit_state *pit_state = &pit->pit_state; 4447837699fSSheng Yang int channel, access; 4457837699fSSheng Yang struct kvm_kpit_channel_state *s; 4467837699fSSheng Yang u32 val = *(u32 *) data; 447bda9020eSMichael S. Tsirkin if (!pit_in_range(addr)) 448bda9020eSMichael S. Tsirkin return -EOPNOTSUPP; 4497837699fSSheng Yang 4507837699fSSheng Yang val &= 0xff; 4517837699fSSheng Yang addr &= KVM_PIT_CHANNEL_MASK; 4527837699fSSheng Yang 4537837699fSSheng Yang mutex_lock(&pit_state->lock); 4547837699fSSheng Yang 4557837699fSSheng Yang if (val != 0) 456a78d9626SJoe Perches pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n", 4577837699fSSheng Yang (unsigned int)addr, len, val); 4587837699fSSheng Yang 4597837699fSSheng Yang if (addr == 3) { 4607837699fSSheng Yang channel = val >> 6; 4617837699fSSheng Yang if (channel == 3) { 4627837699fSSheng Yang /* Read-Back Command. */ 4637837699fSSheng Yang for (channel = 0; channel < 3; channel++) { 4647837699fSSheng Yang if (val & (2 << channel)) { 4657837699fSSheng Yang if (!(val & 0x20)) 46609edea72SRadim Krčmář pit_latch_count(pit, channel); 4677837699fSSheng Yang if (!(val & 0x10)) 46809edea72SRadim Krčmář pit_latch_status(pit, channel); 4697837699fSSheng Yang } 4707837699fSSheng Yang } 4717837699fSSheng Yang } else { 4727837699fSSheng Yang /* Select Counter <channel>. */ 4737837699fSSheng Yang s = &pit_state->channels[channel]; 4747837699fSSheng Yang access = (val >> 4) & KVM_PIT_CHANNEL_MASK; 4757837699fSSheng Yang if (access == 0) { 47609edea72SRadim Krčmář pit_latch_count(pit, channel); 4777837699fSSheng Yang } else { 4787837699fSSheng Yang s->rw_mode = access; 4797837699fSSheng Yang s->read_state = access; 4807837699fSSheng Yang s->write_state = access; 4817837699fSSheng Yang s->mode = (val >> 1) & 7; 4827837699fSSheng Yang if (s->mode > 5) 4837837699fSSheng Yang s->mode -= 4; 4847837699fSSheng Yang s->bcd = val & 1; 4857837699fSSheng Yang } 4867837699fSSheng Yang } 4877837699fSSheng Yang } else { 4887837699fSSheng Yang /* Write Count. */ 4897837699fSSheng Yang s = &pit_state->channels[addr]; 4907837699fSSheng Yang switch (s->write_state) { 4917837699fSSheng Yang default: 4927837699fSSheng Yang case RW_STATE_LSB: 49309edea72SRadim Krčmář pit_load_count(pit, addr, val); 4947837699fSSheng Yang break; 4957837699fSSheng Yang case RW_STATE_MSB: 49609edea72SRadim Krčmář pit_load_count(pit, addr, val << 8); 4977837699fSSheng Yang break; 4987837699fSSheng Yang case RW_STATE_WORD0: 4997837699fSSheng Yang s->write_latch = val; 5007837699fSSheng Yang s->write_state = RW_STATE_WORD1; 5017837699fSSheng Yang break; 5027837699fSSheng Yang case RW_STATE_WORD1: 50309edea72SRadim Krčmář pit_load_count(pit, addr, s->write_latch | (val << 8)); 5047837699fSSheng Yang s->write_state = RW_STATE_WORD0; 5057837699fSSheng Yang break; 5067837699fSSheng Yang } 5077837699fSSheng Yang } 5087837699fSSheng Yang 5097837699fSSheng Yang mutex_unlock(&pit_state->lock); 510bda9020eSMichael S. Tsirkin return 0; 5117837699fSSheng Yang } 5127837699fSSheng Yang 513e32edf4fSNikolay Nikolaev static int pit_ioport_read(struct kvm_vcpu *vcpu, 514e32edf4fSNikolay Nikolaev struct kvm_io_device *this, 5157837699fSSheng Yang gpa_t addr, int len, void *data) 5167837699fSSheng Yang { 517d76685c4SGregory Haskins struct kvm_pit *pit = dev_to_pit(this); 5187837699fSSheng Yang struct kvm_kpit_state *pit_state = &pit->pit_state; 5197837699fSSheng Yang int ret, count; 5207837699fSSheng Yang struct kvm_kpit_channel_state *s; 521bda9020eSMichael S. Tsirkin if (!pit_in_range(addr)) 522bda9020eSMichael S. Tsirkin return -EOPNOTSUPP; 5237837699fSSheng Yang 5247837699fSSheng Yang addr &= KVM_PIT_CHANNEL_MASK; 525ee73f656SMarcelo Tosatti if (addr == 3) 526ee73f656SMarcelo Tosatti return 0; 527ee73f656SMarcelo Tosatti 5287837699fSSheng Yang s = &pit_state->channels[addr]; 5297837699fSSheng Yang 5307837699fSSheng Yang mutex_lock(&pit_state->lock); 5317837699fSSheng Yang 5327837699fSSheng Yang if (s->status_latched) { 5337837699fSSheng Yang s->status_latched = 0; 5347837699fSSheng Yang ret = s->status; 5357837699fSSheng Yang } else if (s->count_latched) { 5367837699fSSheng Yang switch (s->count_latched) { 5377837699fSSheng Yang default: 5387837699fSSheng Yang case RW_STATE_LSB: 5397837699fSSheng Yang ret = s->latched_count & 0xff; 5407837699fSSheng Yang s->count_latched = 0; 5417837699fSSheng Yang break; 5427837699fSSheng Yang case RW_STATE_MSB: 5437837699fSSheng Yang ret = s->latched_count >> 8; 5447837699fSSheng Yang s->count_latched = 0; 5457837699fSSheng Yang break; 5467837699fSSheng Yang case RW_STATE_WORD0: 5477837699fSSheng Yang ret = s->latched_count & 0xff; 5487837699fSSheng Yang s->count_latched = RW_STATE_MSB; 5497837699fSSheng Yang break; 5507837699fSSheng Yang } 5517837699fSSheng Yang } else { 5527837699fSSheng Yang switch (s->read_state) { 5537837699fSSheng Yang default: 5547837699fSSheng Yang case RW_STATE_LSB: 55509edea72SRadim Krčmář count = pit_get_count(pit, addr); 5567837699fSSheng Yang ret = count & 0xff; 5577837699fSSheng Yang break; 5587837699fSSheng Yang case RW_STATE_MSB: 55909edea72SRadim Krčmář count = pit_get_count(pit, addr); 5607837699fSSheng Yang ret = (count >> 8) & 0xff; 5617837699fSSheng Yang break; 5627837699fSSheng Yang case RW_STATE_WORD0: 56309edea72SRadim Krčmář count = pit_get_count(pit, addr); 5647837699fSSheng Yang ret = count & 0xff; 5657837699fSSheng Yang s->read_state = RW_STATE_WORD1; 5667837699fSSheng Yang break; 5677837699fSSheng Yang case RW_STATE_WORD1: 56809edea72SRadim Krčmář count = pit_get_count(pit, addr); 5697837699fSSheng Yang ret = (count >> 8) & 0xff; 5707837699fSSheng Yang s->read_state = RW_STATE_WORD0; 5717837699fSSheng Yang break; 5727837699fSSheng Yang } 5737837699fSSheng Yang } 5747837699fSSheng Yang 5757837699fSSheng Yang if (len > sizeof(ret)) 5767837699fSSheng Yang len = sizeof(ret); 5777837699fSSheng Yang memcpy(data, (char *)&ret, len); 5787837699fSSheng Yang 5797837699fSSheng Yang mutex_unlock(&pit_state->lock); 580bda9020eSMichael S. Tsirkin return 0; 5817837699fSSheng Yang } 5827837699fSSheng Yang 583e32edf4fSNikolay Nikolaev static int speaker_ioport_write(struct kvm_vcpu *vcpu, 584e32edf4fSNikolay Nikolaev struct kvm_io_device *this, 5857837699fSSheng Yang gpa_t addr, int len, const void *data) 5867837699fSSheng Yang { 587d76685c4SGregory Haskins struct kvm_pit *pit = speaker_to_pit(this); 5887837699fSSheng Yang struct kvm_kpit_state *pit_state = &pit->pit_state; 5897837699fSSheng Yang u32 val = *(u32 *) data; 590bda9020eSMichael S. Tsirkin if (addr != KVM_SPEAKER_BASE_ADDRESS) 591bda9020eSMichael S. Tsirkin return -EOPNOTSUPP; 5927837699fSSheng Yang 5937837699fSSheng Yang mutex_lock(&pit_state->lock); 594*b1728622SPaul Durrant if (val & (1 << 1)) 595*b1728622SPaul Durrant pit_state->flags |= KVM_PIT_FLAGS_SPEAKER_DATA_ON; 596*b1728622SPaul Durrant else 597*b1728622SPaul Durrant pit_state->flags &= ~KVM_PIT_FLAGS_SPEAKER_DATA_ON; 59809edea72SRadim Krčmář pit_set_gate(pit, 2, val & 1); 5997837699fSSheng Yang mutex_unlock(&pit_state->lock); 600bda9020eSMichael S. Tsirkin return 0; 6017837699fSSheng Yang } 6027837699fSSheng Yang 603e32edf4fSNikolay Nikolaev static int speaker_ioport_read(struct kvm_vcpu *vcpu, 604e32edf4fSNikolay Nikolaev struct kvm_io_device *this, 6057837699fSSheng Yang gpa_t addr, int len, void *data) 6067837699fSSheng Yang { 607d76685c4SGregory Haskins struct kvm_pit *pit = speaker_to_pit(this); 6087837699fSSheng Yang struct kvm_kpit_state *pit_state = &pit->pit_state; 6097837699fSSheng Yang unsigned int refresh_clock; 6107837699fSSheng Yang int ret; 611bda9020eSMichael S. Tsirkin if (addr != KVM_SPEAKER_BASE_ADDRESS) 612bda9020eSMichael S. Tsirkin return -EOPNOTSUPP; 6137837699fSSheng Yang 6147837699fSSheng Yang /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */ 6157837699fSSheng Yang refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1; 6167837699fSSheng Yang 6177837699fSSheng Yang mutex_lock(&pit_state->lock); 618*b1728622SPaul Durrant ret = (!!(pit_state->flags & KVM_PIT_FLAGS_SPEAKER_DATA_ON) << 1) | 619*b1728622SPaul Durrant pit_get_gate(pit, 2) | (pit_get_out(pit, 2) << 5) | 620*b1728622SPaul Durrant (refresh_clock << 4); 6217837699fSSheng Yang if (len > sizeof(ret)) 6227837699fSSheng Yang len = sizeof(ret); 6237837699fSSheng Yang memcpy(data, (char *)&ret, len); 6247837699fSSheng Yang mutex_unlock(&pit_state->lock); 625bda9020eSMichael S. Tsirkin return 0; 6267837699fSSheng Yang } 6277837699fSSheng Yang 628b39c90b6SRadim Krčmář static void kvm_pit_reset(struct kvm_pit *pit) 6297837699fSSheng Yang { 6307837699fSSheng Yang int i; 631308b0f23SSheng Yang struct kvm_kpit_channel_state *c; 632308b0f23SSheng Yang 633e9f42757SBeth Kon pit->pit_state.flags = 0; 634308b0f23SSheng Yang for (i = 0; i < 3; i++) { 635308b0f23SSheng Yang c = &pit->pit_state.channels[i]; 636308b0f23SSheng Yang c->mode = 0xff; 637308b0f23SSheng Yang c->gate = (i != 2); 63809edea72SRadim Krčmář pit_load_count(pit, i, 0); 639308b0f23SSheng Yang } 640308b0f23SSheng Yang 641fd700a00SRadim Krčmář kvm_pit_reset_reinject(pit); 642308b0f23SSheng Yang } 643308b0f23SSheng Yang 6444780c659SAvi Kivity static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) 6454780c659SAvi Kivity { 6464780c659SAvi Kivity struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); 6474780c659SAvi Kivity 648fd700a00SRadim Krčmář if (!mask) 649fd700a00SRadim Krčmář kvm_pit_reset_reinject(pit); 6504780c659SAvi Kivity } 6514780c659SAvi Kivity 652d76685c4SGregory Haskins static const struct kvm_io_device_ops pit_dev_ops = { 653d76685c4SGregory Haskins .read = pit_ioport_read, 654d76685c4SGregory Haskins .write = pit_ioport_write, 655d76685c4SGregory Haskins }; 656d76685c4SGregory Haskins 657d76685c4SGregory Haskins static const struct kvm_io_device_ops speaker_dev_ops = { 658d76685c4SGregory Haskins .read = speaker_ioport_read, 659d76685c4SGregory Haskins .write = speaker_ioport_write, 660d76685c4SGregory Haskins }; 661d76685c4SGregory Haskins 662c5ff41ceSJan Kiszka struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 663308b0f23SSheng Yang { 6647837699fSSheng Yang struct kvm_pit *pit; 6657837699fSSheng Yang struct kvm_kpit_state *pit_state; 666b6ddf05fSJan Kiszka struct pid *pid; 667b6ddf05fSJan Kiszka pid_t pid_nr; 668090b7affSGregory Haskins int ret; 6697837699fSSheng Yang 670254272ceSBen Gardon pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL_ACCOUNT); 6717837699fSSheng Yang if (!pit) 6727837699fSSheng Yang return NULL; 6737837699fSSheng Yang 6745550af4dSSheng Yang pit->irq_source_id = kvm_request_irq_source_id(kvm); 67510d24821SRadim Krčmář if (pit->irq_source_id < 0) 67610d24821SRadim Krčmář goto fail_request; 6775550af4dSSheng Yang 6787837699fSSheng Yang mutex_init(&pit->pit_state.lock); 67933572ac0SChris Lalancette 680b6ddf05fSJan Kiszka pid = get_pid(task_tgid(current)); 681b6ddf05fSJan Kiszka pid_nr = pid_vnr(pid); 682b6ddf05fSJan Kiszka put_pid(pid); 683b6ddf05fSJan Kiszka 68436da91bdSPetr Mladek pit->worker = kthread_create_worker(0, "kvm-pit/%d", pid_nr); 68536da91bdSPetr Mladek if (IS_ERR(pit->worker)) 68610d24821SRadim Krčmář goto fail_kthread; 68710d24821SRadim Krčmář 6883989144fSPetr Mladek kthread_init_work(&pit->expired, pit_do_work); 6897837699fSSheng Yang 6907837699fSSheng Yang pit->kvm = kvm; 6917837699fSSheng Yang 6927837699fSSheng Yang pit_state = &pit->pit_state; 69326ef1924SAvi Kivity hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 694ab4c1476SRadim Krčmář pit_state->timer.function = pit_timer_fn; 69571474e2fSRadim Krčmář 6963cf57fedSMarcelo Tosatti pit_state->irq_ack_notifier.gsi = 0; 6973cf57fedSMarcelo Tosatti pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; 69871474e2fSRadim Krčmář pit->mask_notifier.func = pit_mask_notifer; 6997837699fSSheng Yang 700308b0f23SSheng Yang kvm_pit_reset(pit); 7017837699fSSheng Yang 70271474e2fSRadim Krčmář kvm_pit_set_reinject(pit, true); 7034780c659SAvi Kivity 704250715a6SPaolo Bonzini mutex_lock(&kvm->slots_lock); 7056b66ac1aSGregory Haskins kvm_iodevice_init(&pit->dev, &pit_dev_ops); 706743eeb0bSSasha Levin ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, 707743eeb0bSSasha Levin KVM_PIT_MEM_LENGTH, &pit->dev); 708090b7affSGregory Haskins if (ret < 0) 70910d24821SRadim Krčmář goto fail_register_pit; 7106b66ac1aSGregory Haskins 7116b66ac1aSGregory Haskins if (flags & KVM_PIT_SPEAKER_DUMMY) { 7126b66ac1aSGregory Haskins kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); 713e93f8a0fSMarcelo Tosatti ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 714743eeb0bSSasha Levin KVM_SPEAKER_BASE_ADDRESS, 4, 715090b7affSGregory Haskins &pit->speaker_dev); 716090b7affSGregory Haskins if (ret < 0) 71710d24821SRadim Krčmář goto fail_register_speaker; 7186b66ac1aSGregory Haskins } 719250715a6SPaolo Bonzini mutex_unlock(&kvm->slots_lock); 7206b66ac1aSGregory Haskins 7217837699fSSheng Yang return pit; 722090b7affSGregory Haskins 72310d24821SRadim Krčmář fail_register_speaker: 724e93f8a0fSMarcelo Tosatti kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 72510d24821SRadim Krčmář fail_register_pit: 726250715a6SPaolo Bonzini mutex_unlock(&kvm->slots_lock); 72771474e2fSRadim Krčmář kvm_pit_set_reinject(pit, false); 72836da91bdSPetr Mladek kthread_destroy_worker(pit->worker); 72910d24821SRadim Krčmář fail_kthread: 73010d24821SRadim Krčmář kvm_free_irq_source_id(kvm, pit->irq_source_id); 73110d24821SRadim Krčmář fail_request: 732090b7affSGregory Haskins kfree(pit); 733090b7affSGregory Haskins return NULL; 7347837699fSSheng Yang } 7357837699fSSheng Yang 7367837699fSSheng Yang void kvm_free_pit(struct kvm *kvm) 7377837699fSSheng Yang { 73808e5ccf3SRadim Krčmář struct kvm_pit *pit = kvm->arch.vpit; 7397837699fSSheng Yang 74008e5ccf3SRadim Krčmář if (pit) { 741fb530729SRadim Krčmář mutex_lock(&kvm->slots_lock); 74208e5ccf3SRadim Krčmář kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 74308e5ccf3SRadim Krčmář kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev); 744fb530729SRadim Krčmář mutex_unlock(&kvm->slots_lock); 74508e5ccf3SRadim Krčmář kvm_pit_set_reinject(pit, false); 74608e5ccf3SRadim Krčmář hrtimer_cancel(&pit->pit_state.timer); 74736da91bdSPetr Mladek kthread_destroy_worker(pit->worker); 74808e5ccf3SRadim Krčmář kvm_free_irq_source_id(kvm, pit->irq_source_id); 74908e5ccf3SRadim Krčmář kfree(pit); 7507837699fSSheng Yang } 7517837699fSSheng Yang } 752