summaryrefslogtreecommitdiffstats
path: root/arch/unicore32/include/asm/bitops.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/unicore32/include/asm/bitops.h')
-rw-r--r--arch/unicore32/include/asm/bitops.h49
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/unicore32/include/asm/bitops.h b/arch/unicore32/include/asm/bitops.h
new file mode 100644
index 000000000..c0cbdbe17
--- /dev/null
+++ b/arch/unicore32/include/asm/bitops.h
@@ -0,0 +1,49 @@
+/*
+ * linux/arch/unicore32/include/asm/bitops.h
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 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_BITOPS_H__
+#define __UNICORE_BITOPS_H__
+
+#define _ASM_GENERIC_BITOPS_FLS_H_
+#define _ASM_GENERIC_BITOPS___FLS_H_
+#define _ASM_GENERIC_BITOPS_FFS_H_
+#define _ASM_GENERIC_BITOPS___FFS_H_
+/*
+ * On UNICORE, those functions can be implemented around
+ * the cntlz instruction for much better code efficiency.
+ */
+
+static inline int fls(int x)
+{
+ int ret;
+
+ asm("cntlz\t%0, %1" : "=r" (ret) : "r" (x) : "cc");
+ ret = 32 - ret;
+
+ return ret;
+}
+
+#define __fls(x) (fls(x) - 1)
+#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
+#define __ffs(x) (ffs(x) - 1)
+
+#include <asm-generic/bitops.h>
+
+/* following definitions: to avoid using codes in lib/find_*.c */
+#define find_next_bit find_next_bit
+#define find_next_zero_bit find_next_zero_bit
+#define find_first_bit find_first_bit
+#define find_first_zero_bit find_first_zero_bit
+
+#include <asm-generic/bitops/find.h>
+
+#endif /* __UNICORE_BITOPS_H__ */