Browse Source

Blackfin: add optimized version of Hamming Weight functions

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Michael Hennerich 15 years ago
parent
commit
0f7b468b6e
2 changed files with 55 additions and 22 deletions
  1. 0 3
      arch/blackfin/Kconfig
  2. 55 19
      arch/blackfin/include/asm/bitops.h

+ 0 - 3
arch/blackfin/Kconfig

@@ -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
 

+ 55 - 19
arch/blackfin/include/asm/bitops.h

@@ -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 */