[MIPS] MT: Improved multithreading support.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/include/asm-mips/smtc_ipi.h b/include/asm-mips/smtc_ipi.h
new file mode 100644
index 0000000..f22c3e2
--- /dev/null
+++ b/include/asm-mips/smtc_ipi.h
@@ -0,0 +1,118 @@
+/*
+ * Definitions used in MIPS MT SMTC "Interprocessor Interrupt" code.
+ */
+#ifndef __ASM_SMTC_IPI_H
+#define __ASM_SMTC_IPI_H
+
+//#define SMTC_IPI_DEBUG
+
+#ifdef SMTC_IPI_DEBUG
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#endif /* SMTC_IPI_DEBUG */
+
+/*
+ * An IPI "message"
+ */
+
+struct smtc_ipi {
+ struct smtc_ipi *flink;
+ int type;
+ void *arg;
+ int dest;
+#ifdef SMTC_IPI_DEBUG
+ int sender;
+ long stamp;
+#endif /* SMTC_IPI_DEBUG */
+};
+
+/*
+ * Defined IPI Types
+ */
+
+#define LINUX_SMP_IPI 1
+#define SMTC_CLOCK_TICK 2
+
+/*
+ * A queue of IPI messages
+ */
+
+struct smtc_ipi_q {
+ struct smtc_ipi *head;
+ spinlock_t lock;
+ struct smtc_ipi *tail;
+ int depth;
+};
+
+extern struct smtc_ipi_q IPIQ[NR_CPUS];
+extern struct smtc_ipi_q freeIPIq;
+
+static inline void smtc_ipi_nq(struct smtc_ipi_q *q, struct smtc_ipi *p)
+{
+ long flags;
+
+ spin_lock_irqsave(&q->lock, flags);
+ if (q->head == NULL)
+ q->head = q->tail = p;
+ else
+ q->tail->flink = p;
+ p->flink = NULL;
+ q->tail = p;
+ q->depth++;
+#ifdef SMTC_IPI_DEBUG
+ p->sender = read_c0_tcbind();
+ p->stamp = read_c0_count();
+#endif /* SMTC_IPI_DEBUG */
+ spin_unlock_irqrestore(&q->lock, flags);
+}
+
+static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q)
+{
+ struct smtc_ipi *p;
+ long flags;
+
+ spin_lock_irqsave(&q->lock, flags);
+ if (q->head == NULL)
+ p = NULL;
+ else {
+ p = q->head;
+ q->head = q->head->flink;
+ q->depth--;
+ /* Arguably unnecessary, but leaves queue cleaner */
+ if (q->head == NULL)
+ q->tail = NULL;
+ }
+ spin_unlock_irqrestore(&q->lock, flags);
+ return p;
+}
+
+static inline void smtc_ipi_req(struct smtc_ipi_q *q, struct smtc_ipi *p)
+{
+ long flags;
+
+ spin_lock_irqsave(&q->lock, flags);
+ if (q->head == NULL) {
+ q->head = q->tail = p;
+ p->flink = NULL;
+ } else {
+ p->flink = q->head;
+ q->head = p;
+ }
+ q->depth++;
+ spin_unlock_irqrestore(&q->lock, flags);
+}
+
+static inline int smtc_ipi_qdepth(struct smtc_ipi_q *q)
+{
+ long flags;
+ int retval;
+
+ spin_lock_irqsave(&q->lock, flags);
+ retval = q->depth;
+ spin_unlock_irqrestore(&q->lock, flags);
+ return retval;
+}
+
+extern void smtc_send_ipi(int cpu, int type, unsigned int action);
+
+#endif /* __ASM_SMTC_IPI_H */