xref: /openbmc/linux/arch/x86/kvm/i8254.h (revision cfbb9be8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __I8254_H
3 #define __I8254_H
4 
5 #include <linux/kthread.h>
6 
7 #include <kvm/iodev.h>
8 
9 struct kvm_kpit_channel_state {
10 	u32 count; /* can be 65536 */
11 	u16 latched_count;
12 	u8 count_latched;
13 	u8 status_latched;
14 	u8 status;
15 	u8 read_state;
16 	u8 write_state;
17 	u8 write_latch;
18 	u8 rw_mode;
19 	u8 mode;
20 	u8 bcd; /* not supported */
21 	u8 gate; /* timer start */
22 	ktime_t count_load_time;
23 };
24 
25 struct kvm_kpit_state {
26 	/* All members before "struct mutex lock" are protected by the lock. */
27 	struct kvm_kpit_channel_state channels[3];
28 	u32 flags;
29 	bool is_periodic;
30 	s64 period; 				/* unit: ns */
31 	struct hrtimer timer;
32 	u32    speaker_data_on;
33 
34 	struct mutex lock;
35 	atomic_t reinject;
36 	atomic_t pending; /* accumulated triggered timers */
37 	atomic_t irq_ack;
38 	struct kvm_irq_ack_notifier irq_ack_notifier;
39 };
40 
41 struct kvm_pit {
42 	struct kvm_io_device dev;
43 	struct kvm_io_device speaker_dev;
44 	struct kvm *kvm;
45 	struct kvm_kpit_state pit_state;
46 	int irq_source_id;
47 	struct kvm_irq_mask_notifier mask_notifier;
48 	struct kthread_worker *worker;
49 	struct kthread_work expired;
50 };
51 
52 #define KVM_PIT_BASE_ADDRESS	    0x40
53 #define KVM_SPEAKER_BASE_ADDRESS    0x61
54 #define KVM_PIT_MEM_LENGTH	    4
55 #define KVM_PIT_FREQ		    1193181
56 #define KVM_MAX_PIT_INTR_INTERVAL   HZ / 100
57 #define KVM_PIT_CHANNEL_MASK	    0x3
58 
59 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
60 void kvm_free_pit(struct kvm *kvm);
61 
62 void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
63 		int hpet_legacy_start);
64 void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject);
65 
66 #endif
67