Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / mn10300 / include / asm / cmpxchg.h

diff --git a/kernel/arch/mn10300/include/asm/cmpxchg.h b/kernel/arch/mn10300/include/asm/cmpxchg.h
new file mode 100644 (file)
index 0000000..97a4aaf
--- /dev/null
+++ b/kernel/arch/mn10300/include/asm/cmpxchg.h
@@ -0,0 +1,115 @@
+/* MN10300 Atomic xchg/cmpxchg operations
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_CMPXCHG_H
+#define _ASM_CMPXCHG_H
+
+#include <asm/irqflags.h>
+
+#ifdef CONFIG_SMP
+#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
+static inline
+unsigned long __xchg(volatile unsigned long *m, unsigned long val)
+{
+       unsigned long status;
+       unsigned long oldval;
+
+       asm volatile(
+               "1:     mov     %4,(_AAR,%3)    \n"
+               "       mov     (_ADR,%3),%1    \n"
+               "       mov     %5,(_ADR,%3)    \n"
+               "       mov     (_ADR,%3),%0    \n"     /* flush */
+               "       mov     (_ASR,%3),%0    \n"
+               "       or      %0,%0           \n"
+               "       bne     1b              \n"
+               : "=&r"(status), "=&r"(oldval), "=m"(*m)
+               : "a"(ATOMIC_OPS_BASE_ADDR), "r"(m), "r"(val)
+               : "memory", "cc");
+
+       return oldval;
+}
+
+static inline unsigned long __cmpxchg(volatile unsigned long *m,
+                                     unsigned long old, unsigned long new)
+{
+       unsigned long status;
+       unsigned long oldval;
+
+       asm volatile(
+               "1:     mov     %4,(_AAR,%3)    \n"
+               "       mov     (_ADR,%3),%1    \n"
+               "       cmp     %5,%1           \n"
+               "       bne     2f              \n"
+               "       mov     %6,(_ADR,%3)    \n"
+               "2:     mov     (_ADR,%3),%0    \n"     /* flush */
+               "       mov     (_ASR,%3),%0    \n"
+               "       or      %0,%0           \n"
+               "       bne     1b              \n"
+               : "=&r"(status), "=&r"(oldval), "=m"(*m)
+               : "a"(ATOMIC_OPS_BASE_ADDR), "r"(m),
+                 "r"(old), "r"(new)
+               : "memory", "cc");
+
+       return oldval;
+}
+#else  /* CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT */
+#error "No SMP atomic operation support!"
+#endif /* CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT */
+
+#else  /* CONFIG_SMP */
+
+/*
+ * Emulate xchg for non-SMP MN10300
+ */
+struct __xchg_dummy { unsigned long a[100]; };
+#define __xg(x) ((struct __xchg_dummy *)(x))
+
+static inline
+unsigned long __xchg(volatile unsigned long *m, unsigned long val)
+{
+       unsigned long oldval;
+       unsigned long flags;
+
+       flags = arch_local_cli_save();
+       oldval = *m;
+       *m = val;
+       arch_local_irq_restore(flags);
+       return oldval;
+}
+
+/*
+ * Emulate cmpxchg for non-SMP MN10300
+ */
+static inline unsigned long __cmpxchg(volatile unsigned long *m,
+                                     unsigned long old, unsigned long new)
+{
+       unsigned long oldval;
+       unsigned long flags;
+
+       flags = arch_local_cli_save();
+       oldval = *m;
+       if (oldval == old)
+               *m = new;
+       arch_local_irq_restore(flags);
+       return oldval;
+}
+
+#endif /* CONFIG_SMP */
+
+#define xchg(ptr, v)                                           \
+       ((__typeof__(*(ptr))) __xchg((unsigned long *)(ptr),    \
+                                    (unsigned long)(v)))
+
+#define cmpxchg(ptr, o, n)                                     \
+       ((__typeof__(*(ptr))) __cmpxchg((unsigned long *)(ptr), \
+                                       (unsigned long)(o),     \
+                                       (unsigned long)(n)))
+
+#endif /* _ASM_CMPXCHG_H */