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authorPeter Tyser <ptyser@xes-inc.com>2010-04-12 22:28:08 -0500
committerWolfgang Denk <wd@denx.de>2010-04-13 09:13:12 +0200
commit819833af39a91fa1c1e8252862bbda6f5a602f7b (patch)
treed5c9d1628643347ab2b5a8085acfa6f96709fda3 /arch/arm/include/asm/atomic.h
parent61f2b38a17f5b21c59f2afe6cf1cbb5f28638cf9 (diff)
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Move architecture-specific includes to arch/$ARCH/include/asm
This helps to clean up the include/ directory so that it only contains non-architecture-specific headers and also matches Linux's directory layout which many U-Boot developers are already familiar with. Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Diffstat (limited to 'arch/arm/include/asm/atomic.h')
-rw-r--r--arch/arm/include/asm/atomic.h113
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
new file mode 100644
index 0000000..ba9e4b7
--- /dev/null
+++ b/arch/arm/include/asm/atomic.h
@@ -0,0 +1,113 @@
+/*
+ * linux/include/asm-arm/atomic.h
+ *
+ * Copyright (c) 1996 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Changelog:
+ * 27-06-1996 RMK Created
+ * 13-04-1997 RMK Made functions atomic!
+ * 07-12-1997 RMK Upgraded for v2.1.
+ * 26-08-1998 PJB Added #ifdef __KERNEL__
+ */
+#ifndef __ASM_ARM_ATOMIC_H
+#define __ASM_ARM_ATOMIC_H
+
+#include <linux/config.h>
+
+#ifdef CONFIG_SMP
+#error SMP not supported
+#endif
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+#ifdef __KERNEL__
+#include <asm/proc/system.h>
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+static inline void atomic_add(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ v->counter += i;
+ local_irq_restore(flags);
+}
+
+static inline void atomic_sub(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ v->counter -= i;
+ local_irq_restore(flags);
+}
+
+static inline void atomic_inc(volatile atomic_t *v)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ v->counter += 1;
+ local_irq_restore(flags);
+}
+
+static inline void atomic_dec(volatile atomic_t *v)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ v->counter -= 1;
+ local_irq_restore(flags);
+}
+
+static inline int atomic_dec_and_test(volatile atomic_t *v)
+{
+ unsigned long flags;
+ int val;
+
+ local_irq_save(flags);
+ val = v->counter;
+ v->counter = val -= 1;
+ local_irq_restore(flags);
+
+ return val == 0;
+}
+
+static inline int atomic_add_negative(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+ int val;
+
+ local_irq_save(flags);
+ val = v->counter;
+ v->counter = val += i;
+ local_irq_restore(flags);
+
+ return val < 0;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ *addr &= ~mask;
+ local_irq_restore(flags);
+}
+
+/* Atomic operations are already serializing on ARM */
+#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()
+
+#endif
+#endif