Blackfin: add optimized version of Hamming Weight functions
authorMichael Hennerich <michael.hennerich@analog.com>
Tue, 22 Dec 2009 11:32:06 +0000 (11:32 +0000)
committerMike Frysinger <vapier@gentoo.org>
Tue, 9 Mar 2010 05:30:47 +0000 (00:30 -0500)
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
arch/blackfin/Kconfig
arch/blackfin/include/asm/bitops.h

index 3bd8e83..b483639 100644 (file)
@@ -45,9 +45,6 @@ config ZONE_DMA
 config GENERIC_FIND_NEXT_BIT
        def_bool y
 
-config GENERIC_HWEIGHT
-       def_bool y
-
 config GENERIC_HARDIRQS
        def_bool y
 
index a2ff3fb..605ba8e 100644 (file)
@@ -7,22 +7,41 @@
 #ifndef _BLACKFIN_BITOPS_H
 #define _BLACKFIN_BITOPS_H
 
-#ifndef CONFIG_SMP
-# include <asm-generic/bitops.h>
-#else
+#include <linux/compiler.h>
+
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
 
 #ifndef _LINUX_BITOPS_H
 #error only <linux/bitops.h> can be included directly
 #endif
 
-#include <linux/compiler.h>
-#include <asm/byteorder.h>     /* swab32 */
-
-#include <asm-generic/bitops/ffs.h>
-#include <asm-generic/bitops/__ffs.h>
 #include <asm-generic/bitops/sched.h>
-#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/ffs.h>
+#include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/ext2-non-atomic.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+#include <asm-generic/bitops/minix.h>
+
+#ifndef CONFIG_SMP
+#include <linux/irqflags.h>
+
+/*
+ * clear_bit may not imply a memory barrier
+ */
+#ifndef smp_mb__before_clear_bit
+#define smp_mb__before_clear_bit()     smp_mb()
+#define smp_mb__after_clear_bit()      smp_mb()
+#endif
+#include <asm-generic/bitops/atomic.h>
+#include <asm-generic/bitops/non-atomic.h>
+#else
 
+#include <asm/byteorder.h>     /* swab32 */
 #include <linux/linkage.h>
 
 asmlinkage int __raw_bit_set_asm(volatile unsigned long *addr, int nr);
@@ -89,19 +108,36 @@ static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
 
 #include <asm-generic/bitops/non-atomic.h>
 
-#include <asm-generic/bitops/find.h>
-#include <asm-generic/bitops/hweight.h>
-#include <asm-generic/bitops/lock.h>
+#endif /* CONFIG_SMP */
 
-#include <asm-generic/bitops/ext2-atomic.h>
-#include <asm-generic/bitops/ext2-non-atomic.h>
+/*
+ * hweightN: returns the hamming weight (i.e. the number
+ * of bits set) of a N-bit word
+ */
 
-#include <asm-generic/bitops/minix.h>
+static inline unsigned int hweight32(unsigned int w)
+{
+       unsigned int res;
 
-#include <asm-generic/bitops/fls.h>
-#include <asm-generic/bitops/__fls.h>
-#include <asm-generic/bitops/fls64.h>
+       __asm__ ("%0.l = ONES %0;"
+               "%0 = %0.l (Z);"
+               : "=d" (res) : "d" (w));
+       return res;
+}
 
-#endif /* CONFIG_SMP */
+static inline unsigned int hweight64(__u64 w)
+{
+       return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w);
+}
+
+static inline unsigned int hweight16(unsigned int w)
+{
+       return hweight32(w & 0xffff);
+}
+
+static inline unsigned int hweight8(unsigned int w)
+{
+       return hweight32(w & 0xff);
+}
 
 #endif                         /* _BLACKFIN_BITOPS_H */