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-rw-r--r--kernel/arch/frv/include/asm/atomic.h200
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diff --git a/kernel/arch/frv/include/asm/atomic.h b/kernel/arch/frv/include/asm/atomic.h
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index 000000000..102190a61
--- /dev/null
+++ b/kernel/arch/frv/include/asm/atomic.h
@@ -0,0 +1,200 @@
+/* atomic.h: atomic operation emulation for FR-V
+ *
+ * For an explanation of how atomic ops work in this arch, see:
+ * Documentation/frv/atomic-ops.txt
+ *
+ * Copyright (C) 2004 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 License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _ASM_ATOMIC_H
+#define _ASM_ATOMIC_H
+
+#include <linux/types.h>
+#include <asm/spr-regs.h>
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+#ifdef CONFIG_SMP
+#error not SMP safe
+#endif
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ *
+ * We do not have SMP systems, so we don't have to deal with that.
+ */
+
+#define ATOMIC_INIT(i) { (i) }
+#define atomic_read(v) ACCESS_ONCE((v)->counter)
+#define atomic_set(v, i) (((v)->counter) = (i))
+
+#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+ unsigned long val;
+
+ asm("0: \n"
+ " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
+ " ckeq icc3,cc7 \n"
+ " ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
+ " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
+ " add%I2 %1,%2,%1 \n"
+ " cst.p %1,%M0 ,cc3,#1 \n"
+ " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
+ " beq icc3,#0,0b \n"
+ : "+U"(v->counter), "=&r"(val)
+ : "NPr"(i)
+ : "memory", "cc7", "cc3", "icc3"
+ );
+
+ return val;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+ unsigned long val;
+
+ asm("0: \n"
+ " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
+ " ckeq icc3,cc7 \n"
+ " ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
+ " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
+ " sub%I2 %1,%2,%1 \n"
+ " cst.p %1,%M0 ,cc3,#1 \n"
+ " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
+ " beq icc3,#0,0b \n"
+ : "+U"(v->counter), "=&r"(val)
+ : "NPr"(i)
+ : "memory", "cc7", "cc3", "icc3"
+ );
+
+ return val;
+}
+
+#else
+
+extern int atomic_add_return(int i, atomic_t *v);
+extern int atomic_sub_return(int i, atomic_t *v);
+
+#endif
+
+static inline int atomic_add_negative(int i, atomic_t *v)
+{
+ return atomic_add_return(i, v) < 0;
+}
+
+static inline void atomic_add(int i, atomic_t *v)
+{
+ atomic_add_return(i, v);
+}
+
+static inline void atomic_sub(int i, atomic_t *v)
+{
+ atomic_sub_return(i, v);
+}
+
+static inline void atomic_inc(atomic_t *v)
+{
+ atomic_add_return(1, v);
+}
+
+static inline void atomic_dec(atomic_t *v)
+{
+ atomic_sub_return(1, v);
+}
+
+#define atomic_dec_return(v) atomic_sub_return(1, (v))
+#define atomic_inc_return(v) atomic_add_return(1, (v))
+
+#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
+#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
+
+/*
+ * 64-bit atomic ops
+ */
+typedef struct {
+ volatile long long counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(i) { (i) }
+
+static inline long long atomic64_read(atomic64_t *v)
+{
+ long long counter;
+
+ asm("ldd%I1 %M1,%0"
+ : "=e"(counter)
+ : "m"(v->counter));
+ return counter;
+}
+
+static inline void atomic64_set(atomic64_t *v, long long i)
+{
+ asm volatile("std%I0 %1,%M0"
+ : "=m"(v->counter)
+ : "e"(i));
+}
+
+extern long long atomic64_inc_return(atomic64_t *v);
+extern long long atomic64_dec_return(atomic64_t *v);
+extern long long atomic64_add_return(long long i, atomic64_t *v);
+extern long long atomic64_sub_return(long long i, atomic64_t *v);
+
+static inline long long atomic64_add_negative(long long i, atomic64_t *v)
+{
+ return atomic64_add_return(i, v) < 0;
+}
+
+static inline void atomic64_add(long long i, atomic64_t *v)
+{
+ atomic64_add_return(i, v);
+}
+
+static inline void atomic64_sub(long long i, atomic64_t *v)
+{
+ atomic64_sub_return(i, v);
+}
+
+static inline void atomic64_inc(atomic64_t *v)
+{
+ atomic64_inc_return(v);
+}
+
+static inline void atomic64_dec(atomic64_t *v)
+{
+ atomic64_dec_return(v);
+}
+
+#define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0)
+#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
+#define atomic64_inc_and_test(v) (atomic64_inc_return((v)) == 0)
+
+#define atomic_cmpxchg(v, old, new) (cmpxchg(&(v)->counter, old, new))
+#define atomic_xchg(v, new) (xchg(&(v)->counter, new))
+#define atomic64_cmpxchg(v, old, new) (__cmpxchg_64(old, new, &(v)->counter))
+#define atomic64_xchg(v, new) (__xchg_64(new, &(v)->counter))
+
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+ c = atomic_read(v);
+ for (;;) {
+ if (unlikely(c == (u)))
+ break;
+ old = atomic_cmpxchg((v), c, c + (a));
+ if (likely(old == c))
+ break;
+ c = old;
+ }
+ return c;
+}
+
+
+#endif /* _ASM_ATOMIC_H */