Re: [RFC][PATCH 1/2] KVM: In-kernel PIT model

Yang, Sheng
2008-01-24T09:29:18Z

[-- Attachment #1: Type: text/plain, Size: 22459 bytes --]

On Wednesday 23 January 2008 17:46:22 Avi Kivity wrote:
> Yang, Sheng wrote:
> > On Tuesday 22 January 2008 21:54:10 Avi Kivity wrote:
> >> Yang, Sheng wrote:
> >>> +
> >>> +static int pit_get_out(struct kvm *kvm, int channel)
> >>> +{
> >>> + struct PITChannelState *c =
> >>> + &kvm->arch.vpit->pit_state.channels[channel];
> >>> + struct kvm_vcpu *vcpu = kvm->vcpus[0];
> >>> + u64 d, t;
> >>> + int out;
> >>> +
> >>> + ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
> >>> +
> >>> + kvm_get_msr(vcpu, MSR_IA32_TIME_STAMP_COUNTER, &t);
> >>> + d = muldiv64(t - c->count_load_time, PIT_FREQ, cpu_khz * 1000);
> >>
> >> I assume this is to correlate the tsc and the pit counters. Doesn't
> >> this break with cpu frequency scaling or with vcpu migrations?
> >
> > I think the cpu frequency scaling will affect TSC, though cpu_khz would
> > be changed along with it.
>
> It breaks the calculation, though.
>
> I suggest moving to the Linux clock API (which is in nanoseconds).
>

I updated patch using ktime_get() (Is it too heavy?).

And currently all the muldiv64() is used to divide 1e9, which can be insteaded
by ">> 30" approximately. What's your opinion?

But I found just now that the patch would break SMP on pae host(guest hang, so
does the old one)... Don't got clue...

--
From f61536abab1d4821c027b9645655c717a90093e7 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Mon, 21 Jan 2008 16:42:37 +0800
Subject: [PATCH] KVM: In-kernel PIT model

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
arch/x86/kvm/Makefile | 3 +-
arch/x86/kvm/i8254.c | 575
++++++++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/i8254.h | 60 +++++
arch/x86/kvm/irq.c | 3 +
arch/x86/kvm/x86.c | 9 +
include/asm-x86/kvm_host.h | 1 +
include/linux/kvm.h | 2 +
7 files changed, 652 insertions(+), 1 deletions(-)
create mode 100644 arch/x86/kvm/i8254.c
create mode 100644 arch/x86/kvm/i8254.h

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index ffdd0b3..4d0c22e 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -6,7 +6,8 @@ common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o
ioapic.o)

EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm

-kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o
+kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \
+ i8254.o
obj-$(CONFIG_KVM) += kvm.o
kvm-intel-objs = vmx.o
obj-$(CONFIG_KVM_INTEL) += kvm-intel.o
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
new file mode 100644
index 0000000..4f1a54a
--- /dev/null
+++ b/arch/x86/kvm/i8254.c
@@ -0,0 +1,575 @@
+/*
+ * 8253/8254 interval timer emulation
+ *
+ * Copyright (c) 2003-2004 Fabrice Bellard
+ * Copyright (c) 2006 Intel Corporation
+ * Copyright (c) 2007 Keir Fraser, XenSource Inc
+ * Copyright (c) 2008 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"), to
deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Authors:
+ * Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
+ * Based on QEMU and Xen.
+ */
+
+#include <linux/kvm_host.h>
+
+#include "i8254.h"
+
+#define pit_debug(fmt, arg...) printk(KERN_WARNING fmt, ##arg)
+/* #define pit_debug(fmt, arg...) */
+
+#ifndef CONFIG_X86_64
+#define mod_64(x, y) ((x) - (y) * div64_64(x, y))
+#else
+#define mod_64(x, y) ((x) % (y))
+#endif
+
+#define RW_STATE_LSB 1
+#define RW_STATE_MSB 2
+#define RW_STATE_WORD0 3
+#define RW_STATE_WORD1 4
+
+/* Compute with 96 bit intermediate result: (a*b)/c */
+static u64 muldiv64(u64 a, u32 b, u32 c)
+{
+ union {
+ u64 ll;
+ struct {
+#ifdef WORDS_BIGENDIAN
+ u32 high, low;
+#else
+ u32 low, high;
+#endif
+ } l;
+ } u, res;
+ u64 rl, rh;
+
+ u.ll = a;
+ 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);
+ return res.ll;
+}
+
+static void pit_set_gate(struct kvm *kvm, int channel, u32 val)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ switch (c->mode) {
+ default:
+ case 0:
+ case 4:
+ /* XXX: just disable/enable counting */
+ break;
+ case 1:
+ case 2:
+ case 3:
+ case 5:
+ /* Restart counting on rising edge. */
+ if (c->gate < val)
+ c->count_load_time = ktime_get();
+ break;
+ }
+
+ c->gate = val;
+}
+
+int pit_get_gate(struct kvm *kvm, int channel)
+{
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ return kvm->arch.vpit->pit_state.channels[channel].gate;
+}
+
+static int pit_get_count(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+ s64 d, t;
+ int counter;
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ d = muldiv64(t, PIT_FREQ, 1e9);
+
+ switch (c->mode) {
+ case 0:
+ case 1:
+ case 4:
+ case 5:
+ counter = (c->count - d) & 0xffff;
+ break;
+ case 3:
+ /* XXX: may be incorrect for odd counts */
+ counter = c->count - (mod_64((2 * d), c->count));
+ break;
+ default:
+ counter = c->count - mod_64(d, c->count);
+ break;
+ }
+ return counter;
+}
+
+static int pit_get_out(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+ s64 d, t;
+ int out;
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ d = muldiv64(t, PIT_FREQ, 1e9);
+
+ switch (c->mode) {
+ default:
+ case 0:
+ out = (d >= c->count);
+ break;
+ case 1:
+ out = (d < c->count);
+ break;
+ case 2:
+ out = ((mod_64(d, c->count) == 0) && (d != 0));
+ break;
+ case 3:
+ out = (mod_64(d, c->count) < ((c->count + 1) >> 1));
+ break;
+ case 4:
+ case 5:
+ out = (d == c->count);
+ break;
+ }
+
+ return out;
+}
+
+static void pit_latch_count(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ if (!c->count_latched) {
+ c->latched_count = pit_get_count(kvm, channel);
+ c->count_latched = c->rw_mode;
+ }
+}
+
+static void pit_latch_status(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ if (!c->status_latched) {
+ /* TODO: Return NULL COUNT (bit 6). */
+ c->status = ((pit_get_out(kvm, channel) << 7) |
+ (c->rw_mode << 4) |
+ (c->mode << 1) |
+ c->bcd);
+ c->status_latched = 1;
+ }
+}
+
+int __pit_timer_fn(struct pit_channel_state *pc)
+{
+ struct pit_timer *pt = &pc->pit_timer;
+ struct kvm_vcpu *vcpu0 = pc->pit_state->pit->kvm->vcpus[0];
+
+ atomic_inc(&pt->pending);
+ if (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);
+
+ return (pt->period == 0 ? 0 : 1);
+}
+
+static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
+{
+ struct pit_channel_state *pc;
+ int restart_timer = 0;
+
+ pc = container_of(data, struct pit_channel_state, pit_timer.timer);
+
+ restart_timer = __pit_timer_fn(pc);
+
+ if (restart_timer)
+ return HRTIMER_RESTART;
+ else
+ return HRTIMER_NORESTART;
+}
+
+static void destroy_pit_timer(struct pit_channel_state *s)
+{
+ pit_debug("pit: execute del timer!\n");
+ hrtimer_cancel(&s->pit_timer.timer);
+}
+
+static void create_pit_timer(struct pit_channel_state *pc,
+ u32 val, int is_period)
+{
+ s64 interval;
+ ktime_t now = pc->pit_timer.timer.base->get_time();
+
+ interval = muldiv64(val, 1e9, PIT_FREQ);
+
+ pit_debug("pit: create pit timer, interval is %llu usec\n", interval);
+
+ /* TODO The new value only affected after the retriggered */
+ hrtimer_cancel(&pc->pit_timer.timer);
+ pc->pit_timer.period = (is_period == 0) ? 0 : interval;
+ pc->pit_timer.timer.function = pit_timer_fn;
+ atomic_set(&pc->pit_timer.pending, 0);
+
+ hrtimer_start(&pc->pit_timer.timer, ktime_add_ns(now, interval),
+ HRTIMER_MODE_ABS);
+}
+
+static void pit_load_count(struct kvm *kvm, int channel, u32 val)
+{
+ struct pit_channel_state *s =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ pit_debug("pit: load_count val is %d, channel is %d\n", val, channel);
+
+ if (val == 0)
+ val = 0x10000;
+
+ s->count_load_time = ktime_get();
+ s->count = val;
+
+ if (channel != 0)
+ return;
+
+ /* Two types of timer
+ * mode 1 is one shot, mode 2 is period, otherwise del timer */
+ switch (s->mode) {
+ case 1:
+ create_pit_timer(s, val, 0);
+ break;
+ case 2:
+ create_pit_timer(s, val, 1);
+ break;
+ default:
+ destroy_pit_timer(s);
+ }
+}
+
+static void pit_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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ int channel, access;
+ struct pit_channel_state *s;
+ u32 val = *(u32 *) data;
+
+ val &= 0xff;
+ addr &= 3;
+
+ mutex_lock(&pit_state->lock);
+
+ if (val != 0)
+ pit_debug("pit: write addr is 0x%x, len is %d, val is 0x%x\n",
+ (unsigned int)addr, len, val);
+
+ if (addr == 3) {
+ channel = val >> 6;
+ if (channel == 3) {
+ /* Read-Back Command. */
+ for (channel = 0; channel < 3; channel++) {
+ s = &pit_state->channels[channel];
+ if (val & (2 << channel)) {
+ if (!(val & 0x20))
+ pit_latch_count(kvm, channel);
+ if (!(val & 0x10))
+ pit_latch_status(kvm, channel);
+ }
+ }
+ } else {
+ /* Select Counter <channel>. */
+ s = &pit_state->channels[channel];
+ access = (val >> 4) & 3;
+ if (access == 0) {
+ pit_latch_count(kvm, channel);
+ } else {
+ s->rw_mode = access;
+ s->read_state = access;
+ s->write_state = access;
+ s->mode = (val >> 1) & 7;
+ if (s->mode > 5)
+ s->mode -= 4;
+ s->bcd = val & 1;
+ }
+ }
+ } else {
+ /* Write Count. */
+ s = &pit_state->channels[addr];
+ switch (s->write_state) {
+ default:
+ case RW_STATE_LSB:
+ pit_load_count(kvm, addr, val);
+ break;
+ case RW_STATE_MSB:
+ pit_load_count(kvm, addr, val << 8);
+ break;
+ case RW_STATE_WORD0:
+ s->write_latch = val;
+ s->write_state = RW_STATE_WORD1;
+ break;
+ case RW_STATE_WORD1:
+ pit_load_count(kvm, addr, s->write_latch | (val << 8));
+ s->write_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ mutex_unlock(&pit_state->lock);
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ int ret, count;
+ struct pit_channel_state *s;
+
+ addr &= 3;
+ s = &pit_state->channels[addr];
+
+ mutex_lock(&pit_state->lock);
+
+ if (s->status_latched) {
+ s->status_latched = 0;
+ ret = s->status;
+ } else if (s->count_latched) {
+ switch (s->count_latched) {
+ default:
+ case RW_STATE_LSB:
+ ret = s->latched_count & 0xff;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_MSB:
+ ret = s->latched_count >> 8;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_WORD0:
+ ret = s->latched_count & 0xff;
+ s->count_latched = RW_STATE_MSB;
+ break;
+ }
+ } else {
+ switch (s->read_state) {
+ default:
+ case RW_STATE_LSB:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ break;
+ case RW_STATE_MSB:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ break;
+ case RW_STATE_WORD0:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ s->read_state = RW_STATE_WORD1;
+ break;
+ case RW_STATE_WORD1:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ s->read_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+
+ mutex_unlock(&pit_state->lock);
+}
+
+static int pit_in_range(struct kvm_io_device *this, gpa_t addr)
+{
+ return ((addr >= PIT_BASE_ADDRESS) &&
+ (addr < PIT_BASE_ADDRESS + PIT_MEM_LENGTH));
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ u32 val = *(u32 *) data;
+
+ 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);
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ unsigned int refresh_clock;
+ int ret;
+
+ /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
+ refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
+
+ mutex_lock(&pit_state->lock);
+ ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(kvm, 2) |
+ (pit_get_out(kvm, 2) << 5) | (refresh_clock << 4));
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+ mutex_unlock(&pit_state->lock);
+}
+
+static int speaker_in_range(struct kvm_io_device *this, gpa_t addr)
+{
+ return (addr == SPEAKER_BASE_ADDRESS);
+}
+
+struct kvm_pit *kvm_create_pit(struct kvm *kvm)
+{
+ int i;
+ struct kvm_pit *pit;
+ struct pit_state *pit_state;
+ struct pit_channel_state *c;
+
+ pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);
+ if (!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);
+
+ kvm->arch.vpit = pit;
+ pit->kvm = kvm;
+
+ pit_state = &pit->pit_state;
+ pit_state->pit = pit;
+ hrtimer_init(&pit_state->channels[0].pit_timer.timer,
+ CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ atomic_set(&pit_state->channels[0].pit_timer.pending, 0);
+ for (i = 0; i < 3; i++) {
+ c = &pit_state->channels[i];
+ c->pit_state = pit_state;
+ c->mode = 0xff;
+ c->gate = (i != 2);
+ pit_load_count(kvm, i, 0);
+ }
+
+ mutex_unlock(&pit->pit_state.lock);
+
+ return pit;
+}
+
+void kvm_free_pit(struct kvm *kvm)
+{
+ struct hrtimer *timer;
+
+ if (kvm->arch.vpit) {
+ mutex_lock(&kvm->arch.vpit->pit_state.lock);
+ timer = &kvm->arch.vpit->pit_state.channels[0].pit_timer.timer;
+ hrtimer_cancel(timer);
+ mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ kfree(kvm->arch.vpit);
+ }
+}
+
+int __inject_pit_timer_irq(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);
+
+ return 1;
+}
+
+void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct pit_channel_state *pc;
+
+ if (pit) {
+ pc = &pit->pit_state.channels[0];
+ if (atomic_read(&pc->pit_timer.pending))
+ __inject_pit_timer_irq(vcpu->kvm);
+ }
+}
+
+void kvm_pit_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct pit_channel_state *pc;
+
+ if (pit) {
+ pc = &pit->pit_state.channels[0];
+ if (atomic_read(&pc->pit_timer.pending) &&
+ (((vcpu->kvm->arch.vpic->pics[0].imr & 1) == 0 &&
+ vcpu->kvm->arch.vpic->pics[0].irq_base == vec) ||
+ vcpu->kvm->arch.vioapic->redirtbl[0].fields.vector == vec)) {
+ atomic_dec(&pc->pit_timer.pending);
+ pc->count_load_time = ktime_get();
+ }
+ }
+}
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
new file mode 100644
index 0000000..7f49886
--- /dev/null
+++ b/arch/x86/kvm/i8254.h
@@ -0,0 +1,60 @@
+#ifndef __I8254_H
+#define __I8254_H
+
+#include "irq.h"
+
+extern unsigned int cpu_khz;
+
+struct pit_timer {
+ struct hrtimer timer;
+ int irq;
+ s64 period; /* unit: ns */
+ s64 scheduled;
+ ktime_t last_update;
+ atomic_t pending;
+};
+
+struct pit_channel_state {
+ int count; /* can be 65536 */
+ u16 latched_count;
+ u8 count_latched;
+ u8 status_latched;
+ u8 status;
+ u8 read_state;
+ u8 write_state;
+ u8 write_latch;
+ u8 rw_mode;
+ u8 mode;
+ u8 bcd; /* not supported */
+ u8 gate; /* timer start */
+ ktime_t count_load_time;
+ struct pit_timer pit_timer;
+ struct pit_state *pit_state;
+};
+
+struct pit_state {
+ struct pit_channel_state channels[3];
+ struct mutex lock;
+ struct kvm_pit *pit;
+ u32 speaker_data_on;
+};
+
+struct kvm_pit {
+ unsigned long base_addresss;
+ struct kvm_io_device dev;
+ struct kvm_io_device speaker_dev;
+ struct kvm *kvm;
+ struct pit_state pit_state;
+};
+
+#define PIT_BASE_ADDRESS 0x40
+#define SPEAKER_BASE_ADDRESS 0x61
+#define PIT_MEM_LENGTH 4
+#define PIT_FREQ 1193181
+
+void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu);
+void kvm_pit_timer_intr_post(struct kvm_vcpu *vcpu, int vec);
+struct kvm_pit *kvm_create_pit(struct kvm *kvm);
+void kvm_free_pit(struct kvm *kvm);
+
+#endif
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index e571475..dbfe21c 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -23,6 +23,7 @@
#include <linux/kvm_host.h>

#include "irq.h"
+#include "i8254.h"

/*
* check if there is pending interrupt without
@@ -66,6 +67,7 @@ EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
{
kvm_inject_apic_timer_irqs(vcpu);
+ kvm_inject_pit_timer_irqs(vcpu);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
@@ -73,6 +75,7 @@ EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
{
kvm_apic_timer_intr_post(vcpu, vec);
+ kvm_pit_timer_intr_post(vcpu, vec);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_timer_intr_post);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8f94a0b..0993fad 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -18,6 +18,7 @@
#include "segment_descriptor.h"
#include "irq.h"
#include "mmu.h"
+#include "i8254.h"

#include <linux/kvm.h>
#include <linux/fs.h>
@@ -680,6 +681,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_USER_MEMORY:
case KVM_CAP_SET_TSS_ADDR:
case KVM_CAP_EXT_CPUID:
+ case KVM_CAP_PIT:
r = 1;
break;
case KVM_CAP_VAPIC:
@@ -1432,6 +1434,12 @@ long kvm_arch_vm_ioctl(struct file *filp,
} else
goto out;
break;
+ case KVM_CREATE_PIT:
+ r = -ENOMEM;
+ kvm->arch.vpit = kvm_create_pit(kvm);
+ if (kvm->arch.vpit)
+ r = 0;
+ break;
case KVM_IRQ_LINE: {
struct kvm_irq_level irq_event;

@@ -3207,6 +3215,7 @@ static void kvm_free_vcpus(struct kvm *kvm)

void kvm_arch_destroy_vm(struct kvm *kvm)
{
+ kvm_free_pit(kvm);
kfree(kvm->arch.vpic);
kfree(kvm->arch.vioapic);
kvm_free_vcpus(kvm);
diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index d6db0de..66dbdd5 100644
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -283,6 +283,7 @@ struct kvm_arch{
struct list_head active_mmu_pages;
struct kvm_pic *vpic;
struct kvm_ioapic *vioapic;
+ struct kvm_pit *vpit;

int round_robin_prev_vcpu;
unsigned int tss_addr;
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 4de4fd2..2f18cfe 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -232,6 +232,7 @@ struct kvm_vapic_addr {
#define KVM_CAP_SET_TSS_ADDR 4
#define KVM_CAP_EXT_CPUID 5
#define KVM_CAP_VAPIC 6
+#define KVM_CAP_PIT 7

/*
* ioctls for VM fds
@@ -255,6 +256,7 @@ struct kvm_vapic_addr {
#define KVM_IRQ_LINE _IOW(KVMIO, 0x61, struct kvm_irq_level)
#define KVM_GET_IRQCHIP _IOWR(KVMIO, 0x62, struct kvm_irqchip)
#define KVM_SET_IRQCHIP _IOR(KVMIO, 0x63, struct kvm_irqchip)
+#define KVM_CREATE_PIT _IO(KVMIO, 0x64)

/*
* ioctls for vcpu fds
--
debian.1.5.3.7.1-dirty

[-- Attachment #2: 0001-KVM-In-kernel-PIT-model.patch --]
[-- Type: text/x-diff, Size: 21110 bytes --]

From f61536abab1d4821c027b9645655c717a90093e7 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Mon, 21 Jan 2008 16:42:37 +0800
Subject: [PATCH] KVM: In-kernel PIT model

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
arch/x86/kvm/Makefile | 3 +-
arch/x86/kvm/i8254.c | 575 ++++++++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/i8254.h | 60 +++++
arch/x86/kvm/irq.c | 3 +
arch/x86/kvm/x86.c | 9 +
include/asm-x86/kvm_host.h | 1 +
include/linux/kvm.h | 2 +
7 files changed, 652 insertions(+), 1 deletions(-)
create mode 100644 arch/x86/kvm/i8254.c
create mode 100644 arch/x86/kvm/i8254.h

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index ffdd0b3..4d0c22e 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -6,7 +6,8 @@ common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o ioapic.o)

EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm

-kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o
+kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \
+ i8254.o
obj-$(CONFIG_KVM) += kvm.o
kvm-intel-objs = vmx.o
obj-$(CONFIG_KVM_INTEL) += kvm-intel.o
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
new file mode 100644
index 0000000..4f1a54a
--- /dev/null
+++ b/arch/x86/kvm/i8254.c
@@ -0,0 +1,575 @@
+/*
+ * 8253/8254 interval timer emulation
+ *
+ * Copyright (c) 2003-2004 Fabrice Bellard
+ * Copyright (c) 2006 Intel Corporation
+ * Copyright (c) 2007 Keir Fraser, XenSource Inc
+ * Copyright (c) 2008 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Authors:
+ * Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
+ * Based on QEMU and Xen.
+ */
+
+#include <linux/kvm_host.h>
+
+#include "i8254.h"
+
+#define pit_debug(fmt, arg...) printk(KERN_WARNING fmt, ##arg)
+/* #define pit_debug(fmt, arg...) */
+
+#ifndef CONFIG_X86_64
+#define mod_64(x, y) ((x) - (y) * div64_64(x, y))
+#else
+#define mod_64(x, y) ((x) % (y))
+#endif
+
+#define RW_STATE_LSB 1
+#define RW_STATE_MSB 2
+#define RW_STATE_WORD0 3
+#define RW_STATE_WORD1 4
+
+/* Compute with 96 bit intermediate result: (a*b)/c */
+static u64 muldiv64(u64 a, u32 b, u32 c)
+{
+ union {
+ u64 ll;
+ struct {
+#ifdef WORDS_BIGENDIAN
+ u32 high, low;
+#else
+ u32 low, high;
+#endif
+ } l;
+ } u, res;
+ u64 rl, rh;
+
+ u.ll = a;
+ 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);
+ return res.ll;
+}
+
+static void pit_set_gate(struct kvm *kvm, int channel, u32 val)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ switch (c->mode) {
+ default:
+ case 0:
+ case 4:
+ /* XXX: just disable/enable counting */
+ break;
+ case 1:
+ case 2:
+ case 3:
+ case 5:
+ /* Restart counting on rising edge. */
+ if (c->gate < val)
+ c->count_load_time = ktime_get();
+ break;
+ }
+
+ c->gate = val;
+}
+
+int pit_get_gate(struct kvm *kvm, int channel)
+{
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ return kvm->arch.vpit->pit_state.channels[channel].gate;
+}
+
+static int pit_get_count(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+ s64 d, t;
+ int counter;
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ d = muldiv64(t, PIT_FREQ, 1e9);
+
+ switch (c->mode) {
+ case 0:
+ case 1:
+ case 4:
+ case 5:
+ counter = (c->count - d) & 0xffff;
+ break;
+ case 3:
+ /* XXX: may be incorrect for odd counts */
+ counter = c->count - (mod_64((2 * d), c->count));
+ break;
+ default:
+ counter = c->count - mod_64(d, c->count);
+ break;
+ }
+ return counter;
+}
+
+static int pit_get_out(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+ s64 d, t;
+ int out;
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+ d = muldiv64(t, PIT_FREQ, 1e9);
+
+ switch (c->mode) {
+ default:
+ case 0:
+ out = (d >= c->count);
+ break;
+ case 1:
+ out = (d < c->count);
+ break;
+ case 2:
+ out = ((mod_64(d, c->count) == 0) && (d != 0));
+ break;
+ case 3:
+ out = (mod_64(d, c->count) < ((c->count + 1) >> 1));
+ break;
+ case 4:
+ case 5:
+ out = (d == c->count);
+ break;
+ }
+
+ return out;
+}
+
+static void pit_latch_count(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ if (!c->count_latched) {
+ c->latched_count = pit_get_count(kvm, channel);
+ c->count_latched = c->rw_mode;
+ }
+}
+
+static void pit_latch_status(struct kvm *kvm, int channel)
+{
+ struct pit_channel_state *c =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ if (!c->status_latched) {
+ /* TODO: Return NULL COUNT (bit 6). */
+ c->status = ((pit_get_out(kvm, channel) << 7) |
+ (c->rw_mode << 4) |
+ (c->mode << 1) |
+ c->bcd);
+ c->status_latched = 1;
+ }
+}
+
+int __pit_timer_fn(struct pit_channel_state *pc)
+{
+ struct pit_timer *pt = &pc->pit_timer;
+ struct kvm_vcpu *vcpu0 = pc->pit_state->pit->kvm->vcpus[0];
+
+ atomic_inc(&pt->pending);
+ if (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);
+
+ return (pt->period == 0 ? 0 : 1);
+}
+
+static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
+{
+ struct pit_channel_state *pc;
+ int restart_timer = 0;
+
+ pc = container_of(data, struct pit_channel_state, pit_timer.timer);
+
+ restart_timer = __pit_timer_fn(pc);
+
+ if (restart_timer)
+ return HRTIMER_RESTART;
+ else
+ return HRTIMER_NORESTART;
+}
+
+static void destroy_pit_timer(struct pit_channel_state *s)
+{
+ pit_debug("pit: execute del timer!\n");
+ hrtimer_cancel(&s->pit_timer.timer);
+}
+
+static void create_pit_timer(struct pit_channel_state *pc,
+ u32 val, int is_period)
+{
+ s64 interval;
+ ktime_t now = pc->pit_timer.timer.base->get_time();
+
+ interval = muldiv64(val, 1e9, PIT_FREQ);
+
+ pit_debug("pit: create pit timer, interval is %llu usec\n", interval);
+
+ /* TODO The new value only affected after the retriggered */
+ hrtimer_cancel(&pc->pit_timer.timer);
+ pc->pit_timer.period = (is_period == 0) ? 0 : interval;
+ pc->pit_timer.timer.function = pit_timer_fn;
+ atomic_set(&pc->pit_timer.pending, 0);
+
+ hrtimer_start(&pc->pit_timer.timer, ktime_add_ns(now, interval),
+ HRTIMER_MODE_ABS);
+}
+
+static void pit_load_count(struct kvm *kvm, int channel, u32 val)
+{
+ struct pit_channel_state *s =
+ &kvm->arch.vpit->pit_state.channels[channel];
+
+ ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ pit_debug("pit: load_count val is %d, channel is %d\n", val, channel);
+
+ if (val == 0)
+ val = 0x10000;
+
+ s->count_load_time = ktime_get();
+ s->count = val;
+
+ if (channel != 0)
+ return;
+
+ /* Two types of timer
+ * mode 1 is one shot, mode 2 is period, otherwise del timer */
+ switch (s->mode) {
+ case 1:
+ create_pit_timer(s, val, 0);
+ break;
+ case 2:
+ create_pit_timer(s, val, 1);
+ break;
+ default:
+ destroy_pit_timer(s);
+ }
+}
+
+static void pit_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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ int channel, access;
+ struct pit_channel_state *s;
+ u32 val = *(u32 *) data;
+
+ val &= 0xff;
+ addr &= 3;
+
+ mutex_lock(&pit_state->lock);
+
+ if (val != 0)
+ pit_debug("pit: write addr is 0x%x, len is %d, val is 0x%x\n",
+ (unsigned int)addr, len, val);
+
+ if (addr == 3) {
+ channel = val >> 6;
+ if (channel == 3) {
+ /* Read-Back Command. */
+ for (channel = 0; channel < 3; channel++) {
+ s = &pit_state->channels[channel];
+ if (val & (2 << channel)) {
+ if (!(val & 0x20))
+ pit_latch_count(kvm, channel);
+ if (!(val & 0x10))
+ pit_latch_status(kvm, channel);
+ }
+ }
+ } else {
+ /* Select Counter <channel>. */
+ s = &pit_state->channels[channel];
+ access = (val >> 4) & 3;
+ if (access == 0) {
+ pit_latch_count(kvm, channel);
+ } else {
+ s->rw_mode = access;
+ s->read_state = access;
+ s->write_state = access;
+ s->mode = (val >> 1) & 7;
+ if (s->mode > 5)
+ s->mode -= 4;
+ s->bcd = val & 1;
+ }
+ }
+ } else {
+ /* Write Count. */
+ s = &pit_state->channels[addr];
+ switch (s->write_state) {
+ default:
+ case RW_STATE_LSB:
+ pit_load_count(kvm, addr, val);
+ break;
+ case RW_STATE_MSB:
+ pit_load_count(kvm, addr, val << 8);
+ break;
+ case RW_STATE_WORD0:
+ s->write_latch = val;
+ s->write_state = RW_STATE_WORD1;
+ break;
+ case RW_STATE_WORD1:
+ pit_load_count(kvm, addr, s->write_latch | (val << 8));
+ s->write_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ mutex_unlock(&pit_state->lock);
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ int ret, count;
+ struct pit_channel_state *s;
+
+ addr &= 3;
+ s = &pit_state->channels[addr];
+
+ mutex_lock(&pit_state->lock);
+
+ if (s->status_latched) {
+ s->status_latched = 0;
+ ret = s->status;
+ } else if (s->count_latched) {
+ switch (s->count_latched) {
+ default:
+ case RW_STATE_LSB:
+ ret = s->latched_count & 0xff;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_MSB:
+ ret = s->latched_count >> 8;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_WORD0:
+ ret = s->latched_count & 0xff;
+ s->count_latched = RW_STATE_MSB;
+ break;
+ }
+ } else {
+ switch (s->read_state) {
+ default:
+ case RW_STATE_LSB:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ break;
+ case RW_STATE_MSB:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ break;
+ case RW_STATE_WORD0:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ s->read_state = RW_STATE_WORD1;
+ break;
+ case RW_STATE_WORD1:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ s->read_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+
+ mutex_unlock(&pit_state->lock);
+}
+
+static int pit_in_range(struct kvm_io_device *this, gpa_t addr)
+{
+ return ((addr >= PIT_BASE_ADDRESS) &&
+ (addr < PIT_BASE_ADDRESS + PIT_MEM_LENGTH));
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ u32 val = *(u32 *) data;
+
+ 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);
+}
+
+static void 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 pit_state *pit_state = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+ unsigned int refresh_clock;
+ int ret;
+
+ /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
+ refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
+
+ mutex_lock(&pit_state->lock);
+ ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(kvm, 2) |
+ (pit_get_out(kvm, 2) << 5) | (refresh_clock << 4));
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+ mutex_unlock(&pit_state->lock);
+}
+
+static int speaker_in_range(struct kvm_io_device *this, gpa_t addr)
+{
+ return (addr == SPEAKER_BASE_ADDRESS);
+}
+
+struct kvm_pit *kvm_create_pit(struct kvm *kvm)
+{
+ int i;
+ struct kvm_pit *pit;
+ struct pit_state *pit_state;
+ struct pit_channel_state *c;
+
+ pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);
+ if (!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);
+
+ kvm->arch.vpit = pit;
+ pit->kvm = kvm;
+
+ pit_state = &pit->pit_state;
+ pit_state->pit = pit;
+ hrtimer_init(&pit_state->channels[0].pit_timer.timer,
+ CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ atomic_set(&pit_state->channels[0].pit_timer.pending, 0);
+ for (i = 0; i < 3; i++) {
+ c = &pit_state->channels[i];
+ c->pit_state = pit_state;
+ c->mode = 0xff;
+ c->gate = (i != 2);
+ pit_load_count(kvm, i, 0);
+ }
+
+ mutex_unlock(&pit->pit_state.lock);
+
+ return pit;
+}
+
+void kvm_free_pit(struct kvm *kvm)
+{
+ struct hrtimer *timer;
+
+ if (kvm->arch.vpit) {
+ mutex_lock(&kvm->arch.vpit->pit_state.lock);
+ timer = &kvm->arch.vpit->pit_state.channels[0].pit_timer.timer;
+ hrtimer_cancel(timer);
+ mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ kfree(kvm->arch.vpit);
+ }
+}
+
+int __inject_pit_timer_irq(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);
+
+ return 1;
+}
+
+void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct pit_channel_state *pc;
+
+ if (pit) {
+ pc = &pit->pit_state.channels[0];
+ if (atomic_read(&pc->pit_timer.pending))
+ __inject_pit_timer_irq(vcpu->kvm);
+ }
+}
+
+void kvm_pit_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct pit_channel_state *pc;
+
+ if (pit) {
+ pc = &pit->pit_state.channels[0];
+ if (atomic_read(&pc->pit_timer.pending) &&
+ (((vcpu->kvm->arch.vpic->pics[0].imr & 1) == 0 &&
+ vcpu->kvm->arch.vpic->pics[0].irq_base == vec) ||
+ vcpu->kvm->arch.vioapic->redirtbl[0].fields.vector == vec)) {
+ atomic_dec(&pc->pit_timer.pending);
+ pc->count_load_time = ktime_get();
+ }
+ }
+}
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
new file mode 100644
index 0000000..7f49886
--- /dev/null
+++ b/arch/x86/kvm/i8254.h
@@ -0,0 +1,60 @@
+#ifndef __I8254_H
+#define __I8254_H
+
+#include "irq.h"
+
+extern unsigned int cpu_khz;
+
+struct pit_timer {
+ struct hrtimer timer;
+ int irq;
+ s64 period; /* unit: ns */
+ s64 scheduled;
+ ktime_t last_update;
+ atomic_t pending;
+};
+
+struct pit_channel_state {
+ int count; /* can be 65536 */
+ u16 latched_count;
+ u8 count_latched;
+ u8 status_latched;
+ u8 status;
+ u8 read_state;
+ u8 write_state;
+ u8 write_latch;
+ u8 rw_mode;
+ u8 mode;
+ u8 bcd; /* not supported */
+ u8 gate; /* timer start */
+ ktime_t count_load_time;
+ struct pit_timer pit_timer;
+ struct pit_state *pit_state;
+};
+
+struct pit_state {
+ struct pit_channel_state channels[3];
+ struct mutex lock;
+ struct kvm_pit *pit;
+ u32 speaker_data_on;
+};
+
+struct kvm_pit {
+ unsigned long base_addresss;
+ struct kvm_io_device dev;
+ struct kvm_io_device speaker_dev;
+ struct kvm *kvm;
+ struct pit_state pit_state;
+};
+
+#define PIT_BASE_ADDRESS 0x40
+#define SPEAKER_BASE_ADDRESS 0x61
+#define PIT_MEM_LENGTH 4
+#define PIT_FREQ 1193181
+
+void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu);
+void kvm_pit_timer_intr_post(struct kvm_vcpu *vcpu, int vec);
+struct kvm_pit *kvm_create_pit(struct kvm *kvm);
+void kvm_free_pit(struct kvm *kvm);
+
+#endif
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index e571475..dbfe21c 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -23,6 +23,7 @@
#include <linux/kvm_host.h>

#include "irq.h"
+#include "i8254.h"

/*
* check if there is pending interrupt without
@@ -66,6 +67,7 @@ EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
{
kvm_inject_apic_timer_irqs(vcpu);
+ kvm_inject_pit_timer_irqs(vcpu);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
@@ -73,6 +75,7 @@ EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
{
kvm_apic_timer_intr_post(vcpu, vec);
+ kvm_pit_timer_intr_post(vcpu, vec);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_timer_intr_post);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8f94a0b..0993fad 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -18,6 +18,7 @@
#include "segment_descriptor.h"
#include "irq.h"
#include "mmu.h"
+#include "i8254.h"

#include <linux/kvm.h>
#include <linux/fs.h>
@@ -680,6 +681,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_USER_MEMORY:
case KVM_CAP_SET_TSS_ADDR:
case KVM_CAP_EXT_CPUID:
+ case KVM_CAP_PIT:
r = 1;
break;
case KVM_CAP_VAPIC:
@@ -1432,6 +1434,12 @@ long kvm_arch_vm_ioctl(struct file *filp,
} else
goto out;
break;
+ case KVM_CREATE_PIT:
+ r = -ENOMEM;
+ kvm->arch.vpit = kvm_create_pit(kvm);
+ if (kvm->arch.vpit)
+ r = 0;
+ break;
case KVM_IRQ_LINE: {
struct kvm_irq_level irq_event;

@@ -3207,6 +3215,7 @@ static void kvm_free_vcpus(struct kvm *kvm)

void kvm_arch_destroy_vm(struct kvm *kvm)
{
+ kvm_free_pit(kvm);
kfree(kvm->arch.vpic);
kfree(kvm->arch.vioapic);
kvm_free_vcpus(kvm);
diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index d6db0de..66dbdd5 100644
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -283,6 +283,7 @@ struct kvm_arch{
struct list_head active_mmu_pages;
struct kvm_pic *vpic;
struct kvm_ioapic *vioapic;
+ struct kvm_pit *vpit;

int round_robin_prev_vcpu;
unsigned int tss_addr;
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 4de4fd2..2f18cfe 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -232,6 +232,7 @@ struct kvm_vapic_addr {
#define KVM_CAP_SET_TSS_ADDR 4
#define KVM_CAP_EXT_CPUID 5
#define KVM_CAP_VAPIC 6
+#define KVM_CAP_PIT 7

/*
* ioctls for VM fds
@@ -255,6 +256,7 @@ struct kvm_vapic_addr {
#define KVM_IRQ_LINE _IOW(KVMIO, 0x61, struct kvm_irq_level)
#define KVM_GET_IRQCHIP _IOWR(KVMIO, 0x62, struct kvm_irqchip)
#define KVM_SET_IRQCHIP _IOR(KVMIO, 0x63, struct kvm_irqchip)
+#define KVM_CREATE_PIT _IO(KVMIO, 0x64)

/*
* ioctls for vcpu fds
--
debian.1.5.3.7.1-dirty

[-- Attachment #3: Type: text/plain, Size: 228 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org