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authorDavid Howells <dhowells@redhat.com>2009-04-10 01:48:06 +0100
committerDavid Howells <dhowells@redhat.com>2009-04-10 01:48:06 +0100
commite69cc9278831139660cb99bde52908f145338d77 (patch)
treefdc1f002b6036a2220d73c86a253886fa76015dc /arch/frv/include/asm/atomic.h
parent187934655fa0637d4ef3967d4543c6dcccf33058 (diff)
FRV: Move to arch/frv/include/asm/
Move arch headers from include/asm-frv/ to arch/frv/include/asm/. Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'arch/frv/include/asm/atomic.h')
-rw-r--r--arch/frv/include/asm/atomic.h198
1 files changed, 198 insertions, 0 deletions
diff --git a/arch/frv/include/asm/atomic.h b/arch/frv/include/asm/atomic.h
new file mode 100644
index 00000000000..296c35cfb20
--- /dev/null
+++ b/arch/frv/include/asm/atomic.h
@@ -0,0 +1,198 @@
+/* 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/system.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.
+ */
+
+/* Atomic operations are already serializing */
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#define ATOMIC_INIT(i) { (i) }
+#define atomic_read(v) ((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)
+
+/*****************************************************************************/
+/*
+ * exchange value with memory
+ */
+#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
+
+#define xchg(ptr, x) \
+({ \
+ __typeof__(ptr) __xg_ptr = (ptr); \
+ __typeof__(*(ptr)) __xg_orig; \
+ \
+ switch (sizeof(__xg_orig)) { \
+ case 4: \
+ asm volatile( \
+ "swap%I0 %M0,%1" \
+ : "+m"(*__xg_ptr), "=r"(__xg_orig) \
+ : "1"(x) \
+ : "memory" \
+ ); \
+ break; \
+ \
+ default: \
+ __xg_orig = (__typeof__(__xg_orig))0; \
+ asm volatile("break"); \
+ break; \
+ } \
+ \
+ __xg_orig; \
+})
+
+#else
+
+extern uint32_t __xchg_32(uint32_t i, volatile void *v);
+
+#define xchg(ptr, x) \
+({ \
+ __typeof__(ptr) __xg_ptr = (ptr); \
+ __typeof__(*(ptr)) __xg_orig; \
+ \
+ switch (sizeof(__xg_orig)) { \
+ case 4: __xg_orig = (__typeof__(*(ptr))) __xchg_32((uint32_t) x, __xg_ptr); break; \
+ default: \
+ __xg_orig = (__typeof__(__xg_orig))0; \
+ asm volatile("break"); \
+ break; \
+ } \
+ __xg_orig; \
+})
+
+#endif
+
+#define tas(ptr) (xchg((ptr), 1))
+
+#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+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 != (u);
+}
+
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#include <asm-generic/atomic.h>
+#endif /* _ASM_ATOMIC_H */