#include "i8254.h"
#ifndef CONFIG_X86_64
-#define mod_64(x, y) ((x) - (y) * div64_64(x, y))
+#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
#else
#define mod_64(x, y) ((x) % (y))
#endif
rl = (u64)u.l.low * (u64)b;
rh = (u64)u.l.high * (u64)b;
rh += (rl >> 32);
- res.l.high = div64_64(rh, c);
- res.l.low = div64_64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
+ res.l.high = div64_u64(rh, c);
+ res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
return res.ll;
}
c->gate = val;
}
-int pit_get_gate(struct kvm *kvm, int channel)
+static int pit_get_gate(struct kvm *kvm, int channel)
{
WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
return kvm->arch.vpit->pit_state.channels[channel].gate;
}
+static s64 __kpit_elapsed(struct kvm *kvm)
+{
+ s64 elapsed;
+ ktime_t remaining;
+ struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+
+ if (!ps->pit_timer.period)
+ return 0;
+
+ /*
+ * The Counter does not stop when it reaches zero. In
+ * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to
+ * the highest count, either FFFF hex for binary counting
+ * or 9999 for BCD counting, and continues counting.
+ * Modes 2 and 3 are periodic; the Counter reloads
+ * itself with the initial count and continues counting
+ * from there.
+ */
+ remaining = hrtimer_get_remaining(&ps->pit_timer.timer);
+ elapsed = ps->pit_timer.period - ktime_to_ns(remaining);
+ elapsed = mod_64(elapsed, ps->pit_timer.period);
+
+ return elapsed;
+}
+
+static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c,
+ int channel)
+{
+ if (channel == 0)
+ return __kpit_elapsed(kvm);
+
+ return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+}
+
static int pit_get_count(struct kvm *kvm, int channel)
{
struct kvm_kpit_channel_state *c =
WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
- t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ t = kpit_elapsed(kvm, c, channel);
d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
- t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ t = kpit_elapsed(kvm, c, channel);
d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
}
}
-int __pit_timer_fn(struct kvm_kpit_state *ps)
+int pit_has_pending_timer(struct kvm_vcpu *vcpu)
{
- struct kvm_vcpu *vcpu0 = ps->pit->kvm->vcpus[0];
- struct kvm_kpit_timer *pt = &ps->pit_timer;
-
- atomic_inc(&pt->pending);
- smp_mb__after_atomic_inc();
- /* FIXME: handle case where the guest is in guest mode */
- if (vcpu0 && waitqueue_active(&vcpu0->wq)) {
- vcpu0->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
- wake_up_interruptible(&vcpu0->wq);
- }
-
- pt->timer.expires = ktime_add_ns(pt->timer.expires, pt->period);
- pt->scheduled = ktime_to_ns(pt->timer.expires);
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
- return (pt->period == 0 ? 0 : 1);
+ if (pit && kvm_vcpu_is_bsp(vcpu) && pit->pit_state.irq_ack)
+ return atomic_read(&pit->pit_state.pit_timer.pending);
+ return 0;
}
-static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
+static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian)
{
- struct kvm_kpit_state *ps;
- int restart_timer = 0;
+ struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state,
+ irq_ack_notifier);
+ spin_lock(&ps->inject_lock);
+ if (atomic_dec_return(&ps->pit_timer.pending) < 0)
+ atomic_inc(&ps->pit_timer.pending);
+ ps->irq_ack = 1;
+ spin_unlock(&ps->inject_lock);
+}
- ps = container_of(data, struct kvm_kpit_state, pit_timer.timer);
+void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct hrtimer *timer;
- restart_timer = __pit_timer_fn(ps);
+ if (!kvm_vcpu_is_bsp(vcpu) || !pit)
+ return;
- if (restart_timer)
- return HRTIMER_RESTART;
- else
- return HRTIMER_NORESTART;
+ timer = &pit->pit_state.pit_timer.timer;
+ if (hrtimer_cancel(timer))
+ hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
}
-static void destroy_pit_timer(struct kvm_kpit_timer *pt)
+static void destroy_pit_timer(struct kvm_timer *pt)
{
pr_debug("pit: execute del timer!\n");
hrtimer_cancel(&pt->timer);
}
-static void create_pit_timer(struct kvm_kpit_timer *pt, u32 val, int is_period)
+static bool kpit_is_periodic(struct kvm_timer *ktimer)
+{
+ struct kvm_kpit_state *ps = container_of(ktimer, struct kvm_kpit_state,
+ pit_timer);
+ return ps->is_periodic;
+}
+
+static struct kvm_timer_ops kpit_ops = {
+ .is_periodic = kpit_is_periodic,
+};
+
+static void create_pit_timer(struct kvm_kpit_state *ps, u32 val, int is_period)
{
+ struct kvm_timer *pt = &ps->pit_timer;
s64 interval;
interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ);
/* TODO The new value only affected after the retriggered */
hrtimer_cancel(&pt->timer);
- pt->period = (is_period == 0) ? 0 : interval;
- pt->timer.function = pit_timer_fn;
+ pt->period = interval;
+ ps->is_periodic = is_period;
+
+ pt->timer.function = kvm_timer_fn;
+ pt->t_ops = &kpit_ops;
+ pt->kvm = ps->pit->kvm;
+ pt->vcpu = pt->kvm->bsp_vcpu;
+
atomic_set(&pt->pending, 0);
+ ps->irq_ack = 1;
hrtimer_start(&pt->timer, ktime_add_ns(ktime_get(), interval),
HRTIMER_MODE_ABS);
pr_debug("pit: load_count val is %d, channel is %d\n", val, channel);
/*
- * Though spec said the state of 8254 is undefined after power-up,
- * seems some tricky OS like Windows XP depends on IRQ0 interrupt
- * when booting up.
- * So here setting initialize rate for it, and not a specific number
+ * The largest possible initial count is 0; this is equivalent
+ * to 216 for binary counting and 104 for BCD counting.
*/
if (val == 0)
val = 0x10000;
- ps->channels[channel].count_load_time = ktime_get();
ps->channels[channel].count = val;
- if (channel != 0)
+ if (channel != 0) {
+ ps->channels[channel].count_load_time = ktime_get();
return;
+ }
/* Two types of timer
* mode 1 is one shot, mode 2 is period, otherwise del timer */
switch (ps->channels[0].mode) {
+ case 0:
case 1:
- create_pit_timer(&ps->pit_timer, val, 0);
+ /* FIXME: enhance mode 4 precision */
+ case 4:
+ if (!(ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)) {
+ create_pit_timer(ps, val, 0);
+ }
break;
case 2:
- create_pit_timer(&ps->pit_timer, val, 1);
+ case 3:
+ if (!(ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)){
+ create_pit_timer(ps, val, 1);
+ }
break;
default:
destroy_pit_timer(&ps->pit_timer);
}
}
-void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val)
+void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start)
+{
+ u8 saved_mode;
+ if (hpet_legacy_start) {
+ /* save existing mode for later reenablement */
+ saved_mode = kvm->arch.vpit->pit_state.channels[0].mode;
+ kvm->arch.vpit->pit_state.channels[0].mode = 0xff; /* disable timer */
+ pit_load_count(kvm, channel, val);
+ kvm->arch.vpit->pit_state.channels[0].mode = saved_mode;
+ } else {
+ pit_load_count(kvm, channel, val);
+ }
+}
+
+static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)
{
- mutex_lock(&kvm->arch.vpit->pit_state.lock);
- pit_load_count(kvm, channel, val);
- mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ return container_of(dev, struct kvm_pit, dev);
}
-static void pit_ioport_write(struct kvm_io_device *this,
- gpa_t addr, int len, const void *data)
+static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev)
{
- struct kvm_pit *pit = (struct kvm_pit *)this->private;
+ return container_of(dev, struct kvm_pit, speaker_dev);
+}
+
+static inline int pit_in_range(gpa_t addr)
+{
+ return ((addr >= KVM_PIT_BASE_ADDRESS) &&
+ (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
+}
+
+static int pit_ioport_write(struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
+{
+ struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
int channel, access;
struct kvm_kpit_channel_state *s;
u32 val = *(u32 *) data;
+ if (!pit_in_range(addr))
+ return -EOPNOTSUPP;
val &= 0xff;
addr &= KVM_PIT_CHANNEL_MASK;
}
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static void pit_ioport_read(struct kvm_io_device *this,
- gpa_t addr, int len, void *data)
+static int pit_ioport_read(struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
{
- struct kvm_pit *pit = (struct kvm_pit *)this->private;
+ struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
int ret, count;
struct kvm_kpit_channel_state *s;
+ if (!pit_in_range(addr))
+ return -EOPNOTSUPP;
addr &= KVM_PIT_CHANNEL_MASK;
s = &pit_state->channels[addr];
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static int pit_in_range(struct kvm_io_device *this, gpa_t addr)
-{
- return ((addr >= KVM_PIT_BASE_ADDRESS) &&
- (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
-}
-
-static void speaker_ioport_write(struct kvm_io_device *this,
- gpa_t addr, int len, const void *data)
+static int speaker_ioport_write(struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
{
- struct kvm_pit *pit = (struct kvm_pit *)this->private;
+ struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
u32 val = *(u32 *) data;
+ if (addr != KVM_SPEAKER_BASE_ADDRESS)
+ return -EOPNOTSUPP;
mutex_lock(&pit_state->lock);
pit_state->speaker_data_on = (val >> 1) & 1;
pit_set_gate(kvm, 2, val & 1);
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static void speaker_ioport_read(struct kvm_io_device *this,
- gpa_t addr, int len, void *data)
+static int speaker_ioport_read(struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
{
- struct kvm_pit *pit = (struct kvm_pit *)this->private;
+ struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
unsigned int refresh_clock;
int ret;
+ if (addr != KVM_SPEAKER_BASE_ADDRESS)
+ return -EOPNOTSUPP;
/* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
len = sizeof(ret);
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static int speaker_in_range(struct kvm_io_device *this, gpa_t addr)
+void kvm_pit_reset(struct kvm_pit *pit)
{
- return (addr == KVM_SPEAKER_BASE_ADDRESS);
+ int i;
+ struct kvm_kpit_channel_state *c;
+
+ mutex_lock(&pit->pit_state.lock);
+ pit->pit_state.flags = 0;
+ for (i = 0; i < 3; i++) {
+ c = &pit->pit_state.channels[i];
+ c->mode = 0xff;
+ c->gate = (i != 2);
+ pit_load_count(pit->kvm, i, 0);
+ }
+ mutex_unlock(&pit->pit_state.lock);
+
+ atomic_set(&pit->pit_state.pit_timer.pending, 0);
+ pit->pit_state.irq_ack = 1;
}
-struct kvm_pit *kvm_create_pit(struct kvm *kvm)
+static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
+{
+ struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
+
+ if (!mask) {
+ atomic_set(&pit->pit_state.pit_timer.pending, 0);
+ pit->pit_state.irq_ack = 1;
+ }
+}
+
+static const struct kvm_io_device_ops pit_dev_ops = {
+ .read = pit_ioport_read,
+ .write = pit_ioport_write,
+};
+
+static const struct kvm_io_device_ops speaker_dev_ops = {
+ .read = speaker_ioport_read,
+ .write = speaker_ioport_write,
+};
+
+/* Caller must have writers lock on slots_lock */
+struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
{
- int i;
struct kvm_pit *pit;
struct kvm_kpit_state *pit_state;
- struct kvm_kpit_channel_state *c;
+ int ret;
pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);
if (!pit)
return NULL;
+ pit->irq_source_id = kvm_request_irq_source_id(kvm);
+ if (pit->irq_source_id < 0) {
+ kfree(pit);
+ return NULL;
+ }
+
mutex_init(&pit->pit_state.lock);
mutex_lock(&pit->pit_state.lock);
-
- /* Initialize PIO device */
- pit->dev.read = pit_ioport_read;
- pit->dev.write = pit_ioport_write;
- pit->dev.in_range = pit_in_range;
- pit->dev.private = pit;
- kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev);
-
- pit->speaker_dev.read = speaker_ioport_read;
- pit->speaker_dev.write = speaker_ioport_write;
- pit->speaker_dev.in_range = speaker_in_range;
- pit->speaker_dev.private = pit;
- kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev);
+ spin_lock_init(&pit->pit_state.inject_lock);
kvm->arch.vpit = pit;
pit->kvm = kvm;
pit_state->pit = pit;
hrtimer_init(&pit_state->pit_timer.timer,
CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
- atomic_set(&pit_state->pit_timer.pending, 0);
- for (i = 0; i < 3; i++) {
- c = &pit_state->channels[i];
- c->mode = 0xff;
- c->gate = (i != 2);
- pit_load_count(kvm, i, 0);
- }
-
+ pit_state->irq_ack_notifier.gsi = 0;
+ pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
+ kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
+ pit_state->pit_timer.reinject = true;
mutex_unlock(&pit->pit_state.lock);
- pit->pit_state.inject_pending = 1;
+ kvm_pit_reset(pit);
+
+ pit->mask_notifier.func = pit_mask_notifer;
+ kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
+
+ kvm_iodevice_init(&pit->dev, &pit_dev_ops);
+ ret = __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev);
+ if (ret < 0)
+ goto fail;
+
+ if (flags & KVM_PIT_SPEAKER_DUMMY) {
+ kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
+ ret = __kvm_io_bus_register_dev(&kvm->pio_bus,
+ &pit->speaker_dev);
+ if (ret < 0)
+ goto fail_unregister;
+ }
return pit;
+
+fail_unregister:
+ __kvm_io_bus_unregister_dev(&kvm->pio_bus, &pit->dev);
+
+fail:
+ if (pit->irq_source_id >= 0)
+ kvm_free_irq_source_id(kvm, pit->irq_source_id);
+
+ kfree(pit);
+ return NULL;
}
void kvm_free_pit(struct kvm *kvm)
struct hrtimer *timer;
if (kvm->arch.vpit) {
+ kvm_unregister_irq_mask_notifier(kvm, 0,
+ &kvm->arch.vpit->mask_notifier);
+ kvm_unregister_irq_ack_notifier(kvm,
+ &kvm->arch.vpit->pit_state.irq_ack_notifier);
mutex_lock(&kvm->arch.vpit->pit_state.lock);
timer = &kvm->arch.vpit->pit_state.pit_timer.timer;
hrtimer_cancel(timer);
+ kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id);
mutex_unlock(&kvm->arch.vpit->pit_state.lock);
kfree(kvm->arch.vpit);
}
}
-void __inject_pit_timer_intr(struct kvm *kvm)
+static void __inject_pit_timer_intr(struct kvm *kvm)
{
- mutex_lock(&kvm->lock);
- kvm_ioapic_set_irq(kvm->arch.vioapic, 0, 1);
- kvm_ioapic_set_irq(kvm->arch.vioapic, 0, 0);
- kvm_pic_set_irq(pic_irqchip(kvm), 0, 1);
- kvm_pic_set_irq(pic_irqchip(kvm), 0, 0);
- mutex_unlock(&kvm->lock);
+ struct kvm_vcpu *vcpu;
+ int i;
+
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1);
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0);
+
+ /*
+ * Provides NMI watchdog support via Virtual Wire mode.
+ * The route is: PIT -> PIC -> LVT0 in NMI mode.
+ *
+ * Note: Our Virtual Wire implementation is simplified, only
+ * propagating PIT interrupts to all VCPUs when they have set
+ * LVT0 to NMI delivery. Other PIC interrupts are just sent to
+ * VCPU0, and only if its LVT0 is in EXTINT mode.
+ */
+ if (kvm->arch.vapics_in_nmi_mode > 0)
+ kvm_for_each_vcpu(i, vcpu, kvm)
+ kvm_apic_nmi_wd_deliver(vcpu);
}
void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu)
struct kvm *kvm = vcpu->kvm;
struct kvm_kpit_state *ps;
- if (vcpu && pit) {
+ if (pit) {
+ int inject = 0;
ps = &pit->pit_state;
- /* Try to inject pending interrupts when:
- * 1. Pending exists
- * 2. Last interrupt was accepted or waited for too long time*/
- if (atomic_read(&ps->pit_timer.pending) &&
- (ps->inject_pending ||
- (jiffies - ps->last_injected_time
- >= KVM_MAX_PIT_INTR_INTERVAL))) {
- ps->inject_pending = 0;
- __inject_pit_timer_intr(kvm);
- ps->last_injected_time = jiffies;
- }
- }
-}
-
-void kvm_pit_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
-{
- struct kvm_arch *arch = &vcpu->kvm->arch;
- struct kvm_kpit_state *ps;
-
- if (vcpu && arch->vpit) {
- ps = &arch->vpit->pit_state;
- if (atomic_read(&ps->pit_timer.pending) &&
- (((arch->vpic->pics[0].imr & 1) == 0 &&
- arch->vpic->pics[0].irq_base == vec) ||
- (arch->vioapic->redirtbl[0].fields.vector == vec &&
- arch->vioapic->redirtbl[0].fields.mask != 1))) {
- ps->inject_pending = 1;
- atomic_dec(&ps->pit_timer.pending);
- ps->channels[0].count_load_time = ktime_get();
+ /* Try to inject pending interrupts when
+ * last one has been acked.
+ */
+ spin_lock(&ps->inject_lock);
+ if (atomic_read(&ps->pit_timer.pending) && ps->irq_ack) {
+ ps->irq_ack = 0;
+ inject = 1;
}
+ spin_unlock(&ps->inject_lock);
+ if (inject)
+ __inject_pit_timer_intr(kvm);
}
}