1 /*
2 * Definitions used in MIPS MT SMTC "Interprocessor Interrupt" code.
3 */
4 #ifndef __ASM_SMTC_IPI_H
5 #define __ASM_SMTC_IPI_H
6
7 #include <linux/spinlock.h>
8
9 //#define SMTC_IPI_DEBUG
10
11 #ifdef SMTC_IPI_DEBUG
12 #include <asm/mipsregs.h>
13 #include <asm/mipsmtregs.h>
14 #endif /* SMTC_IPI_DEBUG */
15
16 /*
17 * An IPI "message"
18 */
19
20 struct smtc_ipi {
21 struct smtc_ipi *flink;
22 int type;
23 void *arg;
24 int dest;
25 #ifdef SMTC_IPI_DEBUG
26 int sender;
27 long stamp;
28 #endif /* SMTC_IPI_DEBUG */
29 };
30
31 /*
32 * Defined IPI Types
33 */
34
35 #define LINUX_SMP_IPI 1
36 #define SMTC_CLOCK_TICK 2
37 #define IRQ_AFFINITY_IPI 3
38
39 /*
40 * A queue of IPI messages
41 */
42
43 struct smtc_ipi_q {
44 struct smtc_ipi *head;
45 spinlock_t lock;
46 struct smtc_ipi *tail;
47 int depth;
48 };
49
smtc_ipi_nq(struct smtc_ipi_q * q,struct smtc_ipi * p)50 static inline void smtc_ipi_nq(struct smtc_ipi_q *q, struct smtc_ipi *p)
51 {
52 unsigned long flags;
53
54 spin_lock_irqsave(&q->lock, flags);
55 if (q->head == NULL)
56 q->head = q->tail = p;
57 else
58 q->tail->flink = p;
59 p->flink = NULL;
60 q->tail = p;
61 q->depth++;
62 #ifdef SMTC_IPI_DEBUG
63 p->sender = read_c0_tcbind();
64 p->stamp = read_c0_count();
65 #endif /* SMTC_IPI_DEBUG */
66 spin_unlock_irqrestore(&q->lock, flags);
67 }
68
__smtc_ipi_dq(struct smtc_ipi_q * q)69 static inline struct smtc_ipi *__smtc_ipi_dq(struct smtc_ipi_q *q)
70 {
71 struct smtc_ipi *p;
72
73 if (q->head == NULL)
74 p = NULL;
75 else {
76 p = q->head;
77 q->head = q->head->flink;
78 q->depth--;
79 /* Arguably unnecessary, but leaves queue cleaner */
80 if (q->head == NULL)
81 q->tail = NULL;
82 }
83
84 return p;
85 }
86
smtc_ipi_dq(struct smtc_ipi_q * q)87 static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q)
88 {
89 unsigned long flags;
90 struct smtc_ipi *p;
91
92 spin_lock_irqsave(&q->lock, flags);
93 p = __smtc_ipi_dq(q);
94 spin_unlock_irqrestore(&q->lock, flags);
95
96 return p;
97 }
98
smtc_ipi_req(struct smtc_ipi_q * q,struct smtc_ipi * p)99 static inline void smtc_ipi_req(struct smtc_ipi_q *q, struct smtc_ipi *p)
100 {
101 unsigned long flags;
102
103 spin_lock_irqsave(&q->lock, flags);
104 if (q->head == NULL) {
105 q->head = q->tail = p;
106 p->flink = NULL;
107 } else {
108 p->flink = q->head;
109 q->head = p;
110 }
111 q->depth++;
112 spin_unlock_irqrestore(&q->lock, flags);
113 }
114
smtc_ipi_qdepth(struct smtc_ipi_q * q)115 static inline int smtc_ipi_qdepth(struct smtc_ipi_q *q)
116 {
117 unsigned long flags;
118 int retval;
119
120 spin_lock_irqsave(&q->lock, flags);
121 retval = q->depth;
122 spin_unlock_irqrestore(&q->lock, flags);
123 return retval;
124 }
125
126 extern void smtc_send_ipi(int cpu, int type, unsigned int action);
127
128 #endif /* __ASM_SMTC_IPI_H */
129