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-rw-r--r--arch/xtensa/include/asm/bitops.h132
1 files changed, 132 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/bitops.h b/arch/xtensa/include/asm/bitops.h
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+++ b/arch/xtensa/include/asm/bitops.h
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+/*
+ * include/asm-xtensa/bitops.h
+ *
+ * Atomic operations that C can't guarantee us.Useful for resource counting etc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2007 Tensilica Inc.
+ */
+
+#ifndef _XTENSA_BITOPS_H
+#define _XTENSA_BITOPS_H
+
+#ifdef __KERNEL__
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <asm/processor.h>
+#include <asm/byteorder.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_SMP
+# error SMP not supported on this architecture
+#endif
+
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+#include <asm-generic/bitops/atomic.h>
+#include <asm-generic/bitops/non-atomic.h>
+
+#if XCHAL_HAVE_NSA
+
+static inline unsigned long __cntlz (unsigned long x)
+{
+ int lz;
+ asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
+ return lz;
+}
+
+/*
+ * ffz: Find first zero in word. Undefined if no zero exists.
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ */
+
+static inline int ffz(unsigned long x)
+{
+ return 31 - __cntlz(~x & -~x);
+}
+
+/*
+ * __ffs: Find first bit set in word. Return 0 for bit 0
+ */
+
+static inline int __ffs(unsigned long x)
+{
+ return 31 - __cntlz(x & -x);
+}
+
+/*
+ * ffs: Find first bit set in word. This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+
+static inline int ffs(unsigned long x)
+{
+ return 32 - __cntlz(x & -x);
+}
+
+/*
+ * fls: Find last (most-significant) bit set in word.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+
+static inline int fls (unsigned int x)
+{
+ return 32 - __cntlz(x);
+}
+
+/**
+ * __fls - find last (most-significant) set bit in a long word
+ * @word: the word to search
+ *
+ * Undefined if no set bit exists, so code should check against 0 first.
+ */
+static inline unsigned long __fls(unsigned long word)
+{
+ return 31 - __cntlz(word);
+}
+#else
+
+/* Use the generic implementation if we don't have the nsa/nsau instructions. */
+
+# include <asm-generic/bitops/ffs.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>
+
+#endif
+
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/ext2-non-atomic.h>
+
+#ifdef __XTENSA_EL__
+# define ext2_set_bit_atomic(lock,nr,addr) \
+ test_and_set_bit((nr), (unsigned long*)(addr))
+# define ext2_clear_bit_atomic(lock,nr,addr) \
+ test_and_clear_bit((nr), (unsigned long*)(addr))
+#elif defined(__XTENSA_EB__)
+# define ext2_set_bit_atomic(lock,nr,addr) \
+ test_and_set_bit((nr) ^ 0x18, (unsigned long*)(addr))
+# define ext2_clear_bit_atomic(lock,nr,addr) \
+ test_and_clear_bit((nr) ^ 0x18, (unsigned long*)(addr))
+#else
+# error processor byte order undefined!
+#endif
+
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/minix.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _XTENSA_BITOPS_H */