337 lines
		
	
	
		
			9.8 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			337 lines
		
	
	
		
			9.8 KiB
		
	
	
	
		
			C
		
	
	
	
/*
 | 
						|
 * KVM in-kernel PIT (i8254) support
 | 
						|
 *
 | 
						|
 * Copyright (c) 2003-2004 Fabrice Bellard
 | 
						|
 * Copyright (c) 2012      Jan Kiszka, Siemens AG
 | 
						|
 *
 | 
						|
 * 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.
 | 
						|
 */
 | 
						|
#include "qemu/timer.h"
 | 
						|
#include "sysemu/sysemu.h"
 | 
						|
#include "hw/timer/i8254.h"
 | 
						|
#include "hw/timer/i8254_internal.h"
 | 
						|
#include "sysemu/kvm.h"
 | 
						|
 | 
						|
#define KVM_PIT_REINJECT_BIT 0
 | 
						|
 | 
						|
#define CALIBRATION_ROUNDS   3
 | 
						|
 | 
						|
#define KVM_PIT(obj) OBJECT_CHECK(KVMPITState, (obj), TYPE_KVM_I8254)
 | 
						|
#define KVM_PIT_CLASS(class) \
 | 
						|
    OBJECT_CLASS_CHECK(KVMPITClass, (class), TYPE_KVM_I8254)
 | 
						|
#define KVM_PIT_GET_CLASS(obj) \
 | 
						|
    OBJECT_GET_CLASS(KVMPITClass, (obj), TYPE_KVM_I8254)
 | 
						|
 | 
						|
typedef struct KVMPITState {
 | 
						|
    PITCommonState parent_obj;
 | 
						|
 | 
						|
    LostTickPolicy lost_tick_policy;
 | 
						|
    bool vm_stopped;
 | 
						|
    int64_t kernel_clock_offset;
 | 
						|
} KVMPITState;
 | 
						|
 | 
						|
typedef struct KVMPITClass {
 | 
						|
    PITCommonClass parent_class;
 | 
						|
 | 
						|
    DeviceRealize parent_realize;
 | 
						|
} KVMPITClass;
 | 
						|
 | 
						|
static int64_t abs64(int64_t v)
 | 
						|
{
 | 
						|
    return v < 0 ? -v : v;
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_update_clock_offset(KVMPITState *s)
 | 
						|
{
 | 
						|
    int64_t offset, clock_offset;
 | 
						|
    struct timespec ts;
 | 
						|
    int i;
 | 
						|
 | 
						|
    /*
 | 
						|
     * Measure the delta between CLOCK_MONOTONIC, the base used for
 | 
						|
     * kvm_pit_channel_state::count_load_time, and vm_clock. Take the
 | 
						|
     * minimum of several samples to filter out scheduling noise.
 | 
						|
     */
 | 
						|
    clock_offset = INT64_MAX;
 | 
						|
    for (i = 0; i < CALIBRATION_ROUNDS; i++) {
 | 
						|
        offset = qemu_get_clock_ns(vm_clock);
 | 
						|
        clock_gettime(CLOCK_MONOTONIC, &ts);
 | 
						|
        offset -= ts.tv_nsec;
 | 
						|
        offset -= (int64_t)ts.tv_sec * 1000000000;
 | 
						|
        if (abs64(offset) < abs64(clock_offset)) {
 | 
						|
            clock_offset = offset;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    s->kernel_clock_offset = clock_offset;
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_get(PITCommonState *pit)
 | 
						|
{
 | 
						|
    KVMPITState *s = KVM_PIT(pit);
 | 
						|
    struct kvm_pit_state2 kpit;
 | 
						|
    struct kvm_pit_channel_state *kchan;
 | 
						|
    struct PITChannelState *sc;
 | 
						|
    int i, ret;
 | 
						|
 | 
						|
    /* No need to re-read the state if VM is stopped. */
 | 
						|
    if (s->vm_stopped) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    if (kvm_has_pit_state2()) {
 | 
						|
        ret = kvm_vm_ioctl(kvm_state, KVM_GET_PIT2, &kpit);
 | 
						|
        if (ret < 0) {
 | 
						|
            fprintf(stderr, "KVM_GET_PIT2 failed: %s\n", strerror(ret));
 | 
						|
            abort();
 | 
						|
        }
 | 
						|
        pit->channels[0].irq_disabled = kpit.flags & KVM_PIT_FLAGS_HPET_LEGACY;
 | 
						|
    } else {
 | 
						|
        /*
 | 
						|
         * kvm_pit_state2 is superset of kvm_pit_state struct,
 | 
						|
         * so we can use it for KVM_GET_PIT as well.
 | 
						|
         */
 | 
						|
        ret = kvm_vm_ioctl(kvm_state, KVM_GET_PIT, &kpit);
 | 
						|
        if (ret < 0) {
 | 
						|
            fprintf(stderr, "KVM_GET_PIT failed: %s\n", strerror(ret));
 | 
						|
            abort();
 | 
						|
        }
 | 
						|
    }
 | 
						|
    for (i = 0; i < 3; i++) {
 | 
						|
        kchan = &kpit.channels[i];
 | 
						|
        sc = &pit->channels[i];
 | 
						|
        sc->count = kchan->count;
 | 
						|
        sc->latched_count = kchan->latched_count;
 | 
						|
        sc->count_latched = kchan->count_latched;
 | 
						|
        sc->status_latched = kchan->status_latched;
 | 
						|
        sc->status = kchan->status;
 | 
						|
        sc->read_state = kchan->read_state;
 | 
						|
        sc->write_state = kchan->write_state;
 | 
						|
        sc->write_latch = kchan->write_latch;
 | 
						|
        sc->rw_mode = kchan->rw_mode;
 | 
						|
        sc->mode = kchan->mode;
 | 
						|
        sc->bcd = kchan->bcd;
 | 
						|
        sc->gate = kchan->gate;
 | 
						|
        sc->count_load_time = kchan->count_load_time + s->kernel_clock_offset;
 | 
						|
    }
 | 
						|
 | 
						|
    sc = &pit->channels[0];
 | 
						|
    sc->next_transition_time =
 | 
						|
        pit_get_next_transition_time(sc, sc->count_load_time);
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_put(PITCommonState *pit)
 | 
						|
{
 | 
						|
    KVMPITState *s = KVM_PIT(pit);
 | 
						|
    struct kvm_pit_state2 kpit;
 | 
						|
    struct kvm_pit_channel_state *kchan;
 | 
						|
    struct PITChannelState *sc;
 | 
						|
    int i, ret;
 | 
						|
 | 
						|
    /* The offset keeps changing as long as the VM is stopped. */
 | 
						|
    if (s->vm_stopped) {
 | 
						|
        kvm_pit_update_clock_offset(s);
 | 
						|
    }
 | 
						|
 | 
						|
    kpit.flags = pit->channels[0].irq_disabled ? KVM_PIT_FLAGS_HPET_LEGACY : 0;
 | 
						|
    for (i = 0; i < 3; i++) {
 | 
						|
        kchan = &kpit.channels[i];
 | 
						|
        sc = &pit->channels[i];
 | 
						|
        kchan->count = sc->count;
 | 
						|
        kchan->latched_count = sc->latched_count;
 | 
						|
        kchan->count_latched = sc->count_latched;
 | 
						|
        kchan->status_latched = sc->status_latched;
 | 
						|
        kchan->status = sc->status;
 | 
						|
        kchan->read_state = sc->read_state;
 | 
						|
        kchan->write_state = sc->write_state;
 | 
						|
        kchan->write_latch = sc->write_latch;
 | 
						|
        kchan->rw_mode = sc->rw_mode;
 | 
						|
        kchan->mode = sc->mode;
 | 
						|
        kchan->bcd = sc->bcd;
 | 
						|
        kchan->gate = sc->gate;
 | 
						|
        kchan->count_load_time = sc->count_load_time - s->kernel_clock_offset;
 | 
						|
    }
 | 
						|
 | 
						|
    ret = kvm_vm_ioctl(kvm_state,
 | 
						|
                       kvm_has_pit_state2() ? KVM_SET_PIT2 : KVM_SET_PIT,
 | 
						|
                       &kpit);
 | 
						|
    if (ret < 0) {
 | 
						|
        fprintf(stderr, "%s failed: %s\n",
 | 
						|
                kvm_has_pit_state2() ? "KVM_SET_PIT2" : "KVM_SET_PIT",
 | 
						|
                strerror(ret));
 | 
						|
        abort();
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_set_gate(PITCommonState *s, PITChannelState *sc, int val)
 | 
						|
{
 | 
						|
    kvm_pit_get(s);
 | 
						|
 | 
						|
    switch (sc->mode) {
 | 
						|
    default:
 | 
						|
    case 0:
 | 
						|
    case 4:
 | 
						|
        /* XXX: just disable/enable counting */
 | 
						|
        break;
 | 
						|
    case 1:
 | 
						|
    case 2:
 | 
						|
    case 3:
 | 
						|
    case 5:
 | 
						|
        if (sc->gate < val) {
 | 
						|
            /* restart counting on rising edge */
 | 
						|
            sc->count_load_time = qemu_get_clock_ns(vm_clock);
 | 
						|
        }
 | 
						|
        break;
 | 
						|
    }
 | 
						|
    sc->gate = val;
 | 
						|
 | 
						|
    kvm_pit_put(s);
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_get_channel_info(PITCommonState *s, PITChannelState *sc,
 | 
						|
                                     PITChannelInfo *info)
 | 
						|
{
 | 
						|
    kvm_pit_get(s);
 | 
						|
 | 
						|
    pit_get_channel_info_common(s, sc, info);
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_reset(DeviceState *dev)
 | 
						|
{
 | 
						|
    PITCommonState *s = PIT_COMMON(dev);
 | 
						|
 | 
						|
    pit_reset_common(s);
 | 
						|
 | 
						|
    kvm_pit_put(s);
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_irq_control(void *opaque, int n, int enable)
 | 
						|
{
 | 
						|
    PITCommonState *pit = opaque;
 | 
						|
    PITChannelState *s = &pit->channels[0];
 | 
						|
 | 
						|
    kvm_pit_get(pit);
 | 
						|
 | 
						|
    s->irq_disabled = !enable;
 | 
						|
 | 
						|
    kvm_pit_put(pit);
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_vm_state_change(void *opaque, int running,
 | 
						|
                                    RunState state)
 | 
						|
{
 | 
						|
    KVMPITState *s = opaque;
 | 
						|
 | 
						|
    if (running) {
 | 
						|
        kvm_pit_update_clock_offset(s);
 | 
						|
        s->vm_stopped = false;
 | 
						|
    } else {
 | 
						|
        kvm_pit_update_clock_offset(s);
 | 
						|
        kvm_pit_get(PIT_COMMON(s));
 | 
						|
        s->vm_stopped = true;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static void kvm_pit_realizefn(DeviceState *dev, Error **errp)
 | 
						|
{
 | 
						|
    PITCommonState *pit = PIT_COMMON(dev);
 | 
						|
    KVMPITClass *kpc = KVM_PIT_GET_CLASS(dev);
 | 
						|
    KVMPITState *s = KVM_PIT(pit);
 | 
						|
    struct kvm_pit_config config = {
 | 
						|
        .flags = 0,
 | 
						|
    };
 | 
						|
    int ret;
 | 
						|
 | 
						|
    if (kvm_check_extension(kvm_state, KVM_CAP_PIT2)) {
 | 
						|
        ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_PIT2, &config);
 | 
						|
    } else {
 | 
						|
        ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_PIT);
 | 
						|
    }
 | 
						|
    if (ret < 0) {
 | 
						|
        error_setg(errp, "Create kernel PIC irqchip failed: %s",
 | 
						|
                   strerror(ret));
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    switch (s->lost_tick_policy) {
 | 
						|
    case LOST_TICK_DELAY:
 | 
						|
        break; /* enabled by default */
 | 
						|
    case LOST_TICK_DISCARD:
 | 
						|
        if (kvm_check_extension(kvm_state, KVM_CAP_REINJECT_CONTROL)) {
 | 
						|
            struct kvm_reinject_control control = { .pit_reinject = 0 };
 | 
						|
 | 
						|
            ret = kvm_vm_ioctl(kvm_state, KVM_REINJECT_CONTROL, &control);
 | 
						|
            if (ret < 0) {
 | 
						|
                error_setg(errp,
 | 
						|
                           "Can't disable in-kernel PIT reinjection: %s",
 | 
						|
                           strerror(ret));
 | 
						|
                return;
 | 
						|
            }
 | 
						|
        }
 | 
						|
        break;
 | 
						|
    default:
 | 
						|
        error_setg(errp, "Lost tick policy not supported.");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    memory_region_init_reservation(&pit->ioports, NULL, "kvm-pit", 4);
 | 
						|
 | 
						|
    qdev_init_gpio_in(dev, kvm_pit_irq_control, 1);
 | 
						|
 | 
						|
    qemu_add_vm_change_state_handler(kvm_pit_vm_state_change, s);
 | 
						|
 | 
						|
    kpc->parent_realize(dev, errp);
 | 
						|
}
 | 
						|
 | 
						|
static Property kvm_pit_properties[] = {
 | 
						|
    DEFINE_PROP_HEX32("iobase", PITCommonState, iobase,  -1),
 | 
						|
    DEFINE_PROP_LOSTTICKPOLICY("lost_tick_policy", KVMPITState,
 | 
						|
                               lost_tick_policy, LOST_TICK_DELAY),
 | 
						|
    DEFINE_PROP_END_OF_LIST(),
 | 
						|
};
 | 
						|
 | 
						|
static void kvm_pit_class_init(ObjectClass *klass, void *data)
 | 
						|
{
 | 
						|
    KVMPITClass *kpc = KVM_PIT_CLASS(klass);
 | 
						|
    PITCommonClass *k = PIT_COMMON_CLASS(klass);
 | 
						|
    DeviceClass *dc = DEVICE_CLASS(klass);
 | 
						|
 | 
						|
    kpc->parent_realize = dc->realize;
 | 
						|
    dc->realize = kvm_pit_realizefn;
 | 
						|
    k->set_channel_gate = kvm_pit_set_gate;
 | 
						|
    k->get_channel_info = kvm_pit_get_channel_info;
 | 
						|
    k->pre_save = kvm_pit_get;
 | 
						|
    k->post_load = kvm_pit_put;
 | 
						|
    dc->reset = kvm_pit_reset;
 | 
						|
    dc->props = kvm_pit_properties;
 | 
						|
}
 | 
						|
 | 
						|
static const TypeInfo kvm_pit_info = {
 | 
						|
    .name          = TYPE_KVM_I8254,
 | 
						|
    .parent        = TYPE_PIT_COMMON,
 | 
						|
    .instance_size = sizeof(KVMPITState),
 | 
						|
    .class_init = kvm_pit_class_init,
 | 
						|
    .class_size = sizeof(KVMPITClass),
 | 
						|
};
 | 
						|
 | 
						|
static void kvm_pit_register(void)
 | 
						|
{
 | 
						|
    type_register_static(&kvm_pit_info);
 | 
						|
}
 | 
						|
 | 
						|
type_init(kvm_pit_register)
 |