/*
   * 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__
  
  #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);

  }

  
  #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>
  
  #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/sched.h>
  #include <asm-generic/bitops/minix.h>

  
  #endif	/* __KERNEL__ */
  
  #endif	/* _XTENSA_BITOPS_H */