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Diffstat (limited to 'arch/arm/include/asm/bitops.h')
-rw-r--r--arch/arm/include/asm/bitops.h105
1 files changed, 33 insertions, 72 deletions
diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h
index e691ec91e4d3..714440fa2fc6 100644
--- a/arch/arm/include/asm/bitops.h
+++ b/arch/arm/include/asm/bitops.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright 1995, Russell King.
* Various bits and pieces copyrights include:
@@ -25,9 +26,7 @@
#include <linux/compiler.h>
#include <linux/irqflags.h>
-
-#define smp_mb__before_clear_bit() smp_mb()
-#define smp_mb__after_clear_bit() smp_mb()
+#include <asm/barrier.h>
/*
* These functions are the basis of our bit ops.
@@ -37,9 +36,9 @@
static inline void ____atomic_set_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
*p |= mask;
@@ -49,9 +48,9 @@ static inline void ____atomic_set_bit(unsigned int bit, volatile unsigned long *
static inline void ____atomic_clear_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
*p &= ~mask;
@@ -61,9 +60,9 @@ static inline void ____atomic_clear_bit(unsigned int bit, volatile unsigned long
static inline void ____atomic_change_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
*p ^= mask;
@@ -75,9 +74,9 @@ ____atomic_test_and_set_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
unsigned int res;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
res = *p;
@@ -92,9 +91,9 @@ ____atomic_test_and_clear_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
unsigned int res;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
res = *p;
@@ -109,9 +108,9 @@ ____atomic_test_and_change_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
unsigned int res;
- unsigned long mask = 1UL << (bit & 31);
+ unsigned long mask = BIT_MASK(bit);
- p += bit >> 5;
+ p += BIT_WORD(bit);
raw_local_irq_save(flags);
res = *p;
@@ -161,18 +160,20 @@ extern int _test_and_change_bit(int nr, volatile unsigned long * p);
/*
* Little endian assembly bitops. nr = 0 -> byte 0 bit 0.
*/
-extern int _find_first_zero_bit_le(const void * p, unsigned size);
-extern int _find_next_zero_bit_le(const void * p, int size, int offset);
-extern int _find_first_bit_le(const unsigned long *p, unsigned size);
-extern int _find_next_bit_le(const unsigned long *p, int size, int offset);
+unsigned long _find_first_zero_bit_le(const unsigned long *p, unsigned long size);
+unsigned long _find_next_zero_bit_le(const unsigned long *p,
+ unsigned long size, unsigned long offset);
+unsigned long _find_first_bit_le(const unsigned long *p, unsigned long size);
+unsigned long _find_next_bit_le(const unsigned long *p, unsigned long size, unsigned long offset);
/*
* Big endian assembly bitops. nr = 0 -> byte 3 bit 0.
*/
-extern int _find_first_zero_bit_be(const void * p, unsigned size);
-extern int _find_next_zero_bit_be(const void * p, int size, int offset);
-extern int _find_first_bit_be(const unsigned long *p, unsigned size);
-extern int _find_next_bit_be(const unsigned long *p, int size, int offset);
+unsigned long _find_first_zero_bit_be(const unsigned long *p, unsigned long size);
+unsigned long _find_next_zero_bit_be(const unsigned long *p,
+ unsigned long size, unsigned long offset);
+unsigned long _find_first_bit_be(const unsigned long *p, unsigned long size);
+unsigned long _find_next_bit_be(const unsigned long *p, unsigned long size, unsigned long offset);
#ifndef CONFIG_SMP
/*
@@ -216,7 +217,6 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset);
#if __LINUX_ARM_ARCH__ < 5
-#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/fls.h>
@@ -224,59 +224,20 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset);
#else
-static inline int constant_fls(int x)
-{
- int r = 32;
-
- if (!x)
- return 0;
- if (!(x & 0xffff0000u)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xff000000u)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xf0000000u)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xc0000000u)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x80000000u)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-
/*
- * On ARMv5 and above those functions can be implemented around
- * the clz instruction for much better code efficiency.
+ * On ARMv5 and above, the gcc built-ins may rely on the clz instruction
+ * and produce optimal inlined code in all cases. On ARMv7 it is even
+ * better by also using the rbit instruction.
*/
-
-static inline int fls(int x)
-{
- int ret;
-
- if (__builtin_constant_p(x))
- return constant_fls(x);
-
- asm("clz\t%0, %1" : "=r" (ret) : "r" (x));
- 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)
-#define ffz(x) __ffs( ~(x) )
+#include <asm-generic/bitops/builtin-__fls.h>
+#include <asm-generic/bitops/builtin-__ffs.h>
+#include <asm-generic/bitops/builtin-fls.h>
+#include <asm-generic/bitops/builtin-ffs.h>
#endif
+#include <asm-generic/bitops/ffz.h>
+
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>