1 /*
2  * Xen Event Channels (internal header)
3  *
4  * Copyright (C) 2013 Citrix Systems R&D Ltd.
5  *
6  * This source code is licensed under the GNU General Public License,
7  * Version 2 or later.  See the file COPYING for more details.
8  */
9 #ifndef __EVENTS_INTERNAL_H__
10 #define __EVENTS_INTERNAL_H__
11 
12 /* Interrupt types. */
13 enum xen_irq_type {
14 	IRQT_UNBOUND = 0,
15 	IRQT_PIRQ,
16 	IRQT_VIRQ,
17 	IRQT_IPI,
18 	IRQT_EVTCHN
19 };
20 
21 /*
22  * Packed IRQ information:
23  * type - enum xen_irq_type
24  * event channel - irq->event channel mapping
25  * cpu - cpu this event channel is bound to
26  * index - type-specific information:
27  *    PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
28  *           guest, or GSI (real passthrough IRQ) of the device.
29  *    VIRQ - virq number
30  *    IPI - IPI vector
31  *    EVTCHN -
32  */
33 struct irq_info {
34 	struct list_head list;
35 	int refcnt;
36 	enum xen_irq_type type;	/* type */
37 	unsigned irq;
38 	unsigned int evtchn;	/* event channel */
39 	unsigned short cpu;	/* cpu bound */
40 
41 	union {
42 		unsigned short virq;
43 		enum ipi_vector ipi;
44 		struct {
45 			unsigned short pirq;
46 			unsigned short gsi;
47 			unsigned char vector;
48 			unsigned char flags;
49 			uint16_t domid;
50 		} pirq;
51 	} u;
52 };
53 
54 #define PIRQ_NEEDS_EOI	(1 << 0)
55 #define PIRQ_SHAREABLE	(1 << 1)
56 
57 struct evtchn_ops {
58 	unsigned (*max_channels)(void);
59 	unsigned (*nr_channels)(void);
60 
61 	int (*setup)(struct irq_info *info);
62 	void (*bind_to_cpu)(struct irq_info *info, unsigned cpu);
63 
64 	void (*clear_pending)(unsigned port);
65 	void (*set_pending)(unsigned port);
66 	bool (*is_pending)(unsigned port);
67 	bool (*test_and_set_mask)(unsigned port);
68 	void (*mask)(unsigned port);
69 	void (*unmask)(unsigned port);
70 
71 	void (*handle_events)(unsigned cpu);
72 	void (*resume)(void);
73 };
74 
75 extern const struct evtchn_ops *evtchn_ops;
76 
77 extern int **evtchn_to_irq;
78 int get_evtchn_to_irq(unsigned int evtchn);
79 
80 struct irq_info *info_for_irq(unsigned irq);
81 unsigned cpu_from_irq(unsigned irq);
82 unsigned cpu_from_evtchn(unsigned int evtchn);
83 
84 static inline unsigned xen_evtchn_max_channels(void)
85 {
86 	return evtchn_ops->max_channels();
87 }
88 
89 /*
90  * Do any ABI specific setup for a bound event channel before it can
91  * be unmasked and used.
92  */
93 static inline int xen_evtchn_port_setup(struct irq_info *info)
94 {
95 	if (evtchn_ops->setup)
96 		return evtchn_ops->setup(info);
97 	return 0;
98 }
99 
100 static inline void xen_evtchn_port_bind_to_cpu(struct irq_info *info,
101 					       unsigned cpu)
102 {
103 	evtchn_ops->bind_to_cpu(info, cpu);
104 }
105 
106 static inline void clear_evtchn(unsigned port)
107 {
108 	evtchn_ops->clear_pending(port);
109 }
110 
111 static inline void set_evtchn(unsigned port)
112 {
113 	evtchn_ops->set_pending(port);
114 }
115 
116 static inline bool test_evtchn(unsigned port)
117 {
118 	return evtchn_ops->is_pending(port);
119 }
120 
121 static inline bool test_and_set_mask(unsigned port)
122 {
123 	return evtchn_ops->test_and_set_mask(port);
124 }
125 
126 static inline void mask_evtchn(unsigned port)
127 {
128 	return evtchn_ops->mask(port);
129 }
130 
131 static inline void unmask_evtchn(unsigned port)
132 {
133 	return evtchn_ops->unmask(port);
134 }
135 
136 static inline void xen_evtchn_handle_events(unsigned cpu)
137 {
138 	return evtchn_ops->handle_events(cpu);
139 }
140 
141 static inline void xen_evtchn_resume(void)
142 {
143 	if (evtchn_ops->resume)
144 		evtchn_ops->resume();
145 }
146 
147 void xen_evtchn_2l_init(void);
148 int xen_evtchn_fifo_init(void);
149 
150 #endif /* #ifndef __EVENTS_INTERNAL_H__ */
151