i8254.h

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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __I8254_H
#define __I8254_H
 
#include <linux/kthread.h>
 
#include <kvm/iodev.h>
 
struct kvm_kpit_channel_state {
    u32 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 kvm_kpit_state {
    /* All members before "struct mutex lock" are protected by the lock. */
    struct kvm_kpit_channel_state channels[3];
    u32 flags;
    bool is_periodic;
    s64 period;                 /* unit: ns */
    struct hrtimer timer;
 
    struct mutex lock;
    atomic_t reinject;
    atomic_t pending; /* accumulated triggered timers */
    atomic_t irq_ack;
    struct kvm_irq_ack_notifier irq_ack_notifier;
};
 
struct kvm_pit {
    struct kvm_io_device dev;
    struct kvm_io_device speaker_dev;
    struct kvm *kvm;
    struct kvm_kpit_state pit_state;
    int irq_source_id;
    struct kvm_irq_mask_notifier mask_notifier;
    struct kthread_worker *worker;
    struct kthread_work expired;
};
 
#define KVM_PIT_BASE_ADDRESS        0x40
#define KVM_SPEAKER_BASE_ADDRESS    0x61
#define KVM_PIT_MEM_LENGTH      4
#define KVM_PIT_FREQ            1193181
#define KVM_MAX_PIT_INTR_INTERVAL   HZ / 100
#define KVM_PIT_CHANNEL_MASK        0x3
 
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
void kvm_free_pit(struct kvm *kvm);
 
void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
        int hpet_legacy_start);
void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject);
 
#endif