Merge branch 'next-s3c-pm' of git://aeryn.fluff.org.uk/bjdooks/linux into devel

[linux-2.6-omap-h63xx.git] / include / asm-generic / bitops / fls64.h

diff --git a/include/asm-generic/bitops/fls64.h b/include/asm-generic/bitops/fls64.h
index 1b6b17ce2428091e605c8cbda7103b1d42836780..b097cf8444e3f99811ee395144b05a0a237519f3 100644 (file)
--- a/include/asm-generic/bitops/fls64.h
+++ b/include/asm-generic/bitops/fls64.h
@@ -3,12 +3,34 @@
 
 #include <asm/types.h>
 
-static inline int fls64(__u64 x)
+/**
+ * fls64 - find last set bit in a 64-bit word
+ * @x: the word to search
+ *
+ * This is defined in a similar way as the libc and compiler builtin
+ * ffsll, but returns the position of the most significant set bit.
+ *
+ * fls64(value) returns 0 if value is 0 or the position of the last
+ * set bit if value is nonzero. The last (most significant) bit is
+ * at position 64.
+ */
+#if BITS_PER_LONG == 32
+static __always_inline int fls64(__u64 x)
 {
        __u32 h = x >> 32;
        if (h)
                return fls(h) + 32;
        return fls(x);
 }
+#elif BITS_PER_LONG == 64
+static __always_inline int fls64(__u64 x)
+{
+       if (x == 0)
+               return 0;
+       return __fls(x) + 1;
+}
+#else
+#error BITS_PER_LONG not 32 or 64
+#endif
 
 #endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */