Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]

Disintegrate asm/system.h for Unicore32. (Compilation successful)
The implementation details are not changed, but only splitted.
BTW, some codestyles are adjusted.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>

1 files changed, 61 insertions, 0 deletions

diff --git a/arch/unicore32/include/asm/cmpxchg.h b/arch/unicore32/include/asm/cmpxchg.h
new file mode 100644
index 000000000000..df4d5acfd19f
--- /dev/null
+++ b/arch/unicore32/include/asm/cmpxchg.h
@@ -0,0 +1,61 @@
+/*
+ * Atomics xchg/cmpxchg for PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2012 GUAN Xue-tao
+ *
+ * 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.
+ */
+#ifndef __UNICORE_CMPXCHG_H__
+#define __UNICORE_CMPXCHG_H__
+
+/*
+ * Generate a link failure on undefined symbol if the pointer points to a value
+ * of unsupported size.
+ */
+extern void __xchg_bad_pointer(void);
+
+static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
+                int size)
+{
+        unsigned long ret;
+
+        switch (size) {
+        case 1:
+                asm volatile("swapb     %0, %1, [%2]"
+                        : "=&r" (ret)
+                        : "r" (x), "r" (ptr)
+                        : "memory", "cc");
+                break;
+        case 4:
+                asm volatile("swapw     %0, %1, [%2]"
+                        : "=&r" (ret)
+                        : "r" (x), "r" (ptr)
+                        : "memory", "cc");
+                break;
+        default:
+                ret = __xchg_bad_pointer();
+        }
+
+        return ret;
+}
+
+#define xchg(ptr, x) \
+        ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
+
+#include <asm-generic/cmpxchg-local.h>
+
+/*
+ * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
+ * them available.
+ */
+#define cmpxchg_local(ptr, o, n)                                        \
+                ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr),     \
+                (unsigned long)(o), (unsigned long)(n), sizeof(*(ptr))))
+#define cmpxchg64_local(ptr, o, n)                                      \
+                __cmpxchg64_local_generic((ptr), (o), (n))
+
+#include <asm-generic/cmpxchg.h>
+
+#endif /* __UNICORE_CMPXCHG_H__ */