include/asm-mips/smtc_ipi.h

   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 //#define SMTC_IPI_DEBUG
   8
   9 #ifdef SMTC_IPI_DEBUG
  10 #include <asm/mipsregs.h>
  11 #include <asm/mipsmtregs.h>
  12 #endif /* SMTC_IPI_DEBUG */
  13
  14 /*
  15  * An IPI "message"
  16  */
  17
  18 struct smtc_ipi {
  19         struct smtc_ipi *flink;
  20         int type;
  21         void *arg;
  22         int dest;
  23 #ifdef  SMTC_IPI_DEBUG
  24         int sender;
  25         long stamp;
  26 #endif /* SMTC_IPI_DEBUG */
  27 };
  28
  29 /*
  30  * Defined IPI Types
  31  */
  32
  33 #define LINUX_SMP_IPI 1
  34 #define SMTC_CLOCK_TICK 2
  35
  36 /*
  37  * A queue of IPI messages
  38  */
  39
  40 struct smtc_ipi_q {
  41         struct smtc_ipi *head;
  42         spinlock_t lock;
  43         struct smtc_ipi *tail;
  44         int depth;
  45 };
  46
  47 extern struct smtc_ipi_q IPIQ[NR_CPUS];
  48 extern struct smtc_ipi_q freeIPIq;
  49
  50 static inline void smtc_ipi_nq(struct smtc_ipi_q *q, struct smtc_ipi *p)
  51 {
  52         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
  69 static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q)
  70 {
  71         struct smtc_ipi *p;
  72         long flags;
  73
  74         spin_lock_irqsave(&q->lock, flags);
  75         if (q->head == NULL)
  76                 p = NULL;
  77         else {
  78                 p = q->head;
  79                 q->head = q->head->flink;
  80                 q->depth--;
  81                 /* Arguably unnecessary, but leaves queue cleaner */
  82                 if (q->head == NULL)
  83                         q->tail = NULL;
  84         }
  85         spin_unlock_irqrestore(&q->lock, flags);
  86         return p;
  87 }
  88
  89 static inline void smtc_ipi_req(struct smtc_ipi_q *q, struct smtc_ipi *p)
  90 {
  91         long flags;
  92
  93         spin_lock_irqsave(&q->lock, flags);
  94         if (q->head == NULL) {
  95                 q->head = q->tail = p;
  96                 p->flink = NULL;
  97         } else {
  98                 p->flink = q->head;
  99                 q->head = p;
 100         }
 101         q->depth++;
 102         spin_unlock_irqrestore(&q->lock, flags);
 103 }
 104
 105 static inline int smtc_ipi_qdepth(struct smtc_ipi_q *q)
 106 {
 107         long flags;
 108         int retval;
 109
 110         spin_lock_irqsave(&q->lock, flags);
 111         retval = q->depth;
 112         spin_unlock_irqrestore(&q->lock, flags);
 113         return retval;
 114 }
 115
 116 extern void smtc_send_ipi(int cpu, int type, unsigned int action);
 117
 118 #endif /* __ASM_SMTC_IPI_H */