/* SPDX-License-Identifier: GPL-2.0 */

  #ifndef _LINUX_BITREV_H
  #define _LINUX_BITREV_H
  
  #include <linux/types.h>

  #ifdef CONFIG_HAVE_ARCH_BITREVERSE
  #include <asm/bitrev.h>
  
  #define __bitrev32 __arch_bitrev32
  #define __bitrev16 __arch_bitrev16
  #define __bitrev8 __arch_bitrev8

  #else
  extern u8 const byte_rev_table[256];
  static inline u8 __bitrev8(u8 byte)

  {
  	return byte_rev_table[byte];
  }

  static inline u16 __bitrev16(u16 x)
  {
  	return (__bitrev8(x & 0xff) << 8) | __bitrev8(x >> 8);
  }
  
  static inline u32 __bitrev32(u32 x)
  {
  	return (__bitrev16(x & 0xffff) << 16) | __bitrev16(x >> 16);
  }
  
  #endif /* CONFIG_HAVE_ARCH_BITREVERSE */

  #define __bitrev8x4(x)	(__bitrev32(swab32(x)))

  #define __constant_bitrev32(x)	\
  ({					\

  	u32 ___x = x;			\
  	___x = (___x >> 16) | (___x << 16);	\
  	___x = ((___x & (u32)0xFF00FF00UL) >> 8) | ((___x & (u32)0x00FF00FFUL) << 8);	\
  	___x = ((___x & (u32)0xF0F0F0F0UL) >> 4) | ((___x & (u32)0x0F0F0F0FUL) << 4);	\
  	___x = ((___x & (u32)0xCCCCCCCCUL) >> 2) | ((___x & (u32)0x33333333UL) << 2);	\
  	___x = ((___x & (u32)0xAAAAAAAAUL) >> 1) | ((___x & (u32)0x55555555UL) << 1);	\
  	___x;								\

  })
  
  #define __constant_bitrev16(x)	\
  ({					\

  	u16 ___x = x;			\
  	___x = (___x >> 8) | (___x << 8);	\
  	___x = ((___x & (u16)0xF0F0U) >> 4) | ((___x & (u16)0x0F0FU) << 4);	\
  	___x = ((___x & (u16)0xCCCCU) >> 2) | ((___x & (u16)0x3333U) << 2);	\
  	___x = ((___x & (u16)0xAAAAU) >> 1) | ((___x & (u16)0x5555U) << 1);	\
  	___x;								\

  })

  #define __constant_bitrev8x4(x) \
  ({			\

  	u32 ___x = x;	\
  	___x = ((___x & (u32)0xF0F0F0F0UL) >> 4) | ((___x & (u32)0x0F0F0F0FUL) << 4);	\
  	___x = ((___x & (u32)0xCCCCCCCCUL) >> 2) | ((___x & (u32)0x33333333UL) << 2);	\
  	___x = ((___x & (u32)0xAAAAAAAAUL) >> 1) | ((___x & (u32)0x55555555UL) << 1);	\
  	___x;								\

  })

  #define __constant_bitrev8(x)	\
  ({					\

  	u8 ___x = x;			\
  	___x = (___x >> 4) | (___x << 4);	\
  	___x = ((___x & (u8)0xCCU) >> 2) | ((___x & (u8)0x33U) << 2);	\
  	___x = ((___x & (u8)0xAAU) >> 1) | ((___x & (u8)0x55U) << 1);	\
  	___x;								\

  })
  
  #define bitrev32(x) \
  ({			\
  	u32 __x = x;	\
  	__builtin_constant_p(__x) ?	\
  	__constant_bitrev32(__x) :			\
  	__bitrev32(__x);				\
  })
  
  #define bitrev16(x) \
  ({			\
  	u16 __x = x;	\
  	__builtin_constant_p(__x) ?	\
  	__constant_bitrev16(__x) :			\
  	__bitrev16(__x);				\
   })

  #define bitrev8x4(x) \
  ({			\
  	u32 __x = x;	\
  	__builtin_constant_p(__x) ?	\
  	__constant_bitrev8x4(__x) :			\
  	__bitrev8x4(__x);				\
   })

  #define bitrev8(x) \
  ({			\
  	u8 __x = x;	\
  	__builtin_constant_p(__x) ?	\
  	__constant_bitrev8(__x) :			\
  	__bitrev8(__x)	;			\
   })

  #endif /* _LINUX_BITREV_H */