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-rw-r--r--cpukit/score/cpu/powerpc/rtems/score/cpusmplock.h95
1 files changed, 95 insertions, 0 deletions
diff --git a/cpukit/score/cpu/powerpc/rtems/score/cpusmplock.h b/cpukit/score/cpu/powerpc/rtems/score/cpusmplock.h
new file mode 100644
index 0000000000..f5ff9622f4
--- /dev/null
+++ b/cpukit/score/cpu/powerpc/rtems/score/cpusmplock.h
@@ -0,0 +1,95 @@
+/**
+ * @file
+ *
+ * @ingroup ScoreSMPLockPowerPC
+ *
+ * @brief PowerPC SMP Lock Implementation
+ */
+
+/*
+ * Copyright (c) 2013 embedded brains GmbH
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#ifndef _RTEMS_SCORE_POWERPC_SMPLOCK_H
+#define _RTEMS_SCORE_POWERPC_SMPLOCK_H
+
+#include <rtems/score/cpu.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup ScoreSMPLockPowerPC PowerPC SMP Locks
+ *
+ * @ingroup ScoreSMPLock
+ *
+ * A ticket lock implementation is used.
+ *
+ * @{
+ */
+
+typedef struct {
+ uint32_t next_ticket;
+ uint32_t now_serving;
+} CPU_SMP_lock_Control;
+
+#define CPU_SMP_LOCK_INITIALIZER { 0, 0 }
+
+static inline void _CPU_SMP_lock_Initialize( CPU_SMP_lock_Control *lock )
+{
+ lock->next_ticket = 0;
+ lock->now_serving = 0;
+}
+
+static inline void _CPU_SMP_lock_Acquire( CPU_SMP_lock_Control *lock )
+{
+ uint32_t my_ticket;
+ uint32_t next_ticket;
+
+ __asm__ volatile (
+ "1: lwarx %[my_ticket], 0, %[next_ticket_addr]\n"
+ "addi %[next_ticket], %[my_ticket], 1\n"
+ "stwcx. %[next_ticket], 0, [%[next_ticket_addr]]\n"
+ "bne 1b\n"
+ "isync"
+ : [my_ticket] "=&r" (my_ticket),
+ [next_ticket] "=&r" (next_ticket)
+ : [next_ticket_addr] "r" (&lock->next_ticket)
+ : "cc", "memory"
+ );
+
+ while ( my_ticket != lock->now_serving ) {
+ __asm__ volatile ( "" : : : "memory" );
+ }
+}
+
+static inline void _CPU_SMP_lock_Release( CPU_SMP_lock_Control *lock )
+{
+ __asm__ volatile ( "msync" : : : "memory" );
+ ++lock->now_serving;
+}
+
+#define _CPU_SMP_lock_ISR_disable_and_acquire( lock, isr_cookie ) \
+ do { \
+ _CPU_ISR_Disable( isr_cookie ); \
+ _CPU_SMP_lock_Acquire( lock ); \
+ } while (0)
+
+#define _CPU_SMP_lock_Release_and_ISR_enable( lock, isr_cookie ) \
+ do { \
+ _CPU_SMP_lock_Release( lock ); \
+ _CPU_ISR_Enable( isr_cookie ); \
+ } while (0)
+
+/**@}*/
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTEMS_SCORE_POWERPC_SMPLOCK_H */