summaryrefslogtreecommitdiff
path: root/arch/blackfin/include/asm/barrier.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/blackfin/include/asm/barrier.h')
-rw-r--r--arch/blackfin/include/asm/barrier.h86
1 files changed, 0 insertions, 86 deletions
diff --git a/arch/blackfin/include/asm/barrier.h b/arch/blackfin/include/asm/barrier.h
deleted file mode 100644
index 7cca51cae5ff..000000000000
--- a/arch/blackfin/include/asm/barrier.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*
- * Copyright 2004-2009 Analog Devices Inc.
- * Tony Kou (tonyko@lineo.ca)
- *
- * Licensed under the GPL-2 or later
- */
-
-#ifndef _BLACKFIN_BARRIER_H
-#define _BLACKFIN_BARRIER_H
-
-#include <asm/cache.h>
-
-#define nop() __asm__ __volatile__ ("nop;\n\t" : : )
-
-/*
- * Force strict CPU ordering.
- */
-#ifdef CONFIG_SMP
-
-#ifdef __ARCH_SYNC_CORE_DCACHE
-/* Force Core data cache coherence */
-# define mb() do { barrier(); smp_check_barrier(); smp_mark_barrier(); } while (0)
-# define rmb() do { barrier(); smp_check_barrier(); } while (0)
-# define wmb() do { barrier(); smp_mark_barrier(); } while (0)
-/*
- * read_barrier_depends - Flush all pending reads that subsequents reads
- * depend on.
- *
- * No data-dependent reads from memory-like regions are ever reordered
- * over this barrier. All reads preceding this primitive are guaranteed
- * to access memory (but not necessarily other CPUs' caches) before any
- * reads following this primitive that depend on the data return by
- * any of the preceding reads. This primitive is much lighter weight than
- * rmb() on most CPUs, and is never heavier weight than is
- * rmb().
- *
- * These ordering constraints are respected by both the local CPU
- * and the compiler.
- *
- * Ordering is not guaranteed by anything other than these primitives,
- * not even by data dependencies. See the documentation for
- * memory_barrier() for examples and URLs to more information.
- *
- * For example, the following code would force ordering (the initial
- * value of "a" is zero, "b" is one, and "p" is "&a"):
- *
- * <programlisting>
- * CPU 0 CPU 1
- *
- * b = 2;
- * memory_barrier();
- * p = &b; q = p;
- * read_barrier_depends();
- * d = *q;
- * </programlisting>
- *
- * because the read of "*q" depends on the read of "p" and these
- * two reads are separated by a read_barrier_depends(). However,
- * the following code, with the same initial values for "a" and "b":
- *
- * <programlisting>
- * CPU 0 CPU 1
- *
- * a = 2;
- * memory_barrier();
- * b = 3; y = b;
- * read_barrier_depends();
- * x = a;
- * </programlisting>
- *
- * does not enforce ordering, since there is no data dependency between
- * the read of "a" and the read of "b". Therefore, on some CPUs, such
- * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb()
- * in cases like this where there are no data dependencies.
- */
-# define read_barrier_depends() do { barrier(); smp_check_barrier(); } while (0)
-#endif
-
-#endif /* !CONFIG_SMP */
-
-#define __smp_mb__before_atomic() barrier()
-#define __smp_mb__after_atomic() barrier()
-
-#include <asm-generic/barrier.h>
-
-#endif /* _BLACKFIN_BARRIER_H */