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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm/include/asm/bitops.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/arm/include/asm/bitops.h')
-rw-r--r--kernel/arch/arm/include/asm/bitops.h349
1 files changed, 349 insertions, 0 deletions
diff --git a/kernel/arch/arm/include/asm/bitops.h b/kernel/arch/arm/include/asm/bitops.h
new file mode 100644
index 000000000..56380995f
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+++ b/kernel/arch/arm/include/asm/bitops.h
@@ -0,0 +1,349 @@
+/*
+ * Copyright 1995, Russell King.
+ * Various bits and pieces copyrights include:
+ * Linus Torvalds (test_bit).
+ * Big endian support: Copyright 2001, Nicolas Pitre
+ * reworked by rmk.
+ *
+ * bit 0 is the LSB of an "unsigned long" quantity.
+ *
+ * Please note that the code in this file should never be included
+ * from user space. Many of these are not implemented in assembler
+ * since they would be too costly. Also, they require privileged
+ * instructions (which are not available from user mode) to ensure
+ * that they are atomic.
+ */
+
+#ifndef __ASM_ARM_BITOPS_H
+#define __ASM_ARM_BITOPS_H
+
+#ifdef __KERNEL__
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <linux/compiler.h>
+#include <linux/irqflags.h>
+#include <asm/barrier.h>
+
+/*
+ * These functions are the basis of our bit ops.
+ *
+ * First, the atomic bitops. These use native endian.
+ */
+static inline void ____atomic_set_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ *p |= mask;
+ raw_local_irq_restore(flags);
+}
+
+static inline void ____atomic_clear_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ *p &= ~mask;
+ raw_local_irq_restore(flags);
+}
+
+static inline void ____atomic_change_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ *p ^= mask;
+ raw_local_irq_restore(flags);
+}
+
+static inline int
+____atomic_test_and_set_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned int res;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ res = *p;
+ *p = res | mask;
+ raw_local_irq_restore(flags);
+
+ return (res & mask) != 0;
+}
+
+static inline int
+____atomic_test_and_clear_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned int res;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ res = *p;
+ *p = res & ~mask;
+ raw_local_irq_restore(flags);
+
+ return (res & mask) != 0;
+}
+
+static inline int
+____atomic_test_and_change_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned int res;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ raw_local_irq_save(flags);
+ res = *p;
+ *p = res ^ mask;
+ raw_local_irq_restore(flags);
+
+ return (res & mask) != 0;
+}
+
+#include <asm-generic/bitops/non-atomic.h>
+
+/*
+ * A note about Endian-ness.
+ * -------------------------
+ *
+ * When the ARM is put into big endian mode via CR15, the processor
+ * merely swaps the order of bytes within words, thus:
+ *
+ * ------------ physical data bus bits -----------
+ * D31 ... D24 D23 ... D16 D15 ... D8 D7 ... D0
+ * little byte 3 byte 2 byte 1 byte 0
+ * big byte 0 byte 1 byte 2 byte 3
+ *
+ * This means that reading a 32-bit word at address 0 returns the same
+ * value irrespective of the endian mode bit.
+ *
+ * Peripheral devices should be connected with the data bus reversed in
+ * "Big Endian" mode. ARM Application Note 61 is applicable, and is
+ * available from http://www.arm.com/.
+ *
+ * The following assumes that the data bus connectivity for big endian
+ * mode has been followed.
+ *
+ * Note that bit 0 is defined to be 32-bit word bit 0, not byte 0 bit 0.
+ */
+
+/*
+ * Native endian assembly bitops. nr = 0 -> word 0 bit 0.
+ */
+extern void _set_bit(int nr, volatile unsigned long * p);
+extern void _clear_bit(int nr, volatile unsigned long * p);
+extern void _change_bit(int nr, volatile unsigned long * p);
+extern int _test_and_set_bit(int nr, volatile unsigned long * p);
+extern int _test_and_clear_bit(int nr, volatile unsigned long * p);
+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);
+
+/*
+ * 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);
+
+#ifndef CONFIG_SMP
+/*
+ * The __* form of bitops are non-atomic and may be reordered.
+ */
+#define ATOMIC_BITOP(name,nr,p) \
+ (__builtin_constant_p(nr) ? ____atomic_##name(nr, p) : _##name(nr,p))
+#else
+#define ATOMIC_BITOP(name,nr,p) _##name(nr,p)
+#endif
+
+/*
+ * Native endian atomic definitions.
+ */
+#define set_bit(nr,p) ATOMIC_BITOP(set_bit,nr,p)
+#define clear_bit(nr,p) ATOMIC_BITOP(clear_bit,nr,p)
+#define change_bit(nr,p) ATOMIC_BITOP(change_bit,nr,p)
+#define test_and_set_bit(nr,p) ATOMIC_BITOP(test_and_set_bit,nr,p)
+#define test_and_clear_bit(nr,p) ATOMIC_BITOP(test_and_clear_bit,nr,p)
+#define test_and_change_bit(nr,p) ATOMIC_BITOP(test_and_change_bit,nr,p)
+
+#ifndef __ARMEB__
+/*
+ * These are the little endian, atomic definitions.
+ */
+#define find_first_zero_bit(p,sz) _find_first_zero_bit_le(p,sz)
+#define find_next_zero_bit(p,sz,off) _find_next_zero_bit_le(p,sz,off)
+#define find_first_bit(p,sz) _find_first_bit_le(p,sz)
+#define find_next_bit(p,sz,off) _find_next_bit_le(p,sz,off)
+
+#else
+/*
+ * These are the big endian, atomic definitions.
+ */
+#define find_first_zero_bit(p,sz) _find_first_zero_bit_be(p,sz)
+#define find_next_zero_bit(p,sz,off) _find_next_zero_bit_be(p,sz,off)
+#define find_first_bit(p,sz) _find_first_bit_be(p,sz)
+#define find_next_bit(p,sz,off) _find_next_bit_be(p,sz,off)
+
+#endif
+
+#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>
+#include <asm-generic/bitops/ffs.h>
+
+#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. __clz returns
+ * the number of leading zeros, zero input will return 32, and
+ * 0x80000000 will return 0.
+ */
+static inline unsigned int __clz(unsigned int x)
+{
+ unsigned int ret;
+
+ asm("clz\t%0, %1" : "=r" (ret) : "r" (x));
+
+ return ret;
+}
+
+/*
+ * fls() returns zero if the input is zero, otherwise returns the bit
+ * position of the last set bit, where the LSB is 1 and MSB is 32.
+ */
+static inline int fls(int x)
+{
+ if (__builtin_constant_p(x))
+ return constant_fls(x);
+
+ return 32 - __clz(x);
+}
+
+/*
+ * __fls() returns the bit position of the last bit set, where the
+ * LSB is 0 and MSB is 31. Zero input is undefined.
+ */
+static inline unsigned long __fls(unsigned long x)
+{
+ return fls(x) - 1;
+}
+
+/*
+ * ffs() returns zero if the input was zero, otherwise returns the bit
+ * position of the first set bit, where the LSB is 1 and MSB is 32.
+ */
+static inline int ffs(int x)
+{
+ return fls(x & -x);
+}
+
+/*
+ * __ffs() returns the bit position of the first bit set, where the
+ * LSB is 0 and MSB is 31. Zero input is undefined.
+ */
+static inline unsigned long __ffs(unsigned long x)
+{
+ return ffs(x) - 1;
+}
+
+#define ffz(x) __ffs( ~(x) )
+
+#endif
+
+#include <asm-generic/bitops/fls64.h>
+
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/lock.h>
+
+#ifdef __ARMEB__
+
+static inline int find_first_zero_bit_le(const void *p, unsigned size)
+{
+ return _find_first_zero_bit_le(p, size);
+}
+#define find_first_zero_bit_le find_first_zero_bit_le
+
+static inline int find_next_zero_bit_le(const void *p, int size, int offset)
+{
+ return _find_next_zero_bit_le(p, size, offset);
+}
+#define find_next_zero_bit_le find_next_zero_bit_le
+
+static inline int find_next_bit_le(const void *p, int size, int offset)
+{
+ return _find_next_bit_le(p, size, offset);
+}
+#define find_next_bit_le find_next_bit_le
+
+#endif
+
+#include <asm-generic/bitops/le.h>
+
+/*
+ * Ext2 is defined to use little-endian byte ordering.
+ */
+#include <asm-generic/bitops/ext2-atomic-setbit.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _ARM_BITOPS_H */