arch/parisc/include/uapi/asm/swab.h

   1 #ifndef _PARISC_SWAB_H
   2 #define _PARISC_SWAB_H
   3
   4 #include <asm/bitsperlong.h>
   5 #include <linux/types.h>
   6 #include <linux/compiler.h>
   7
   8 #define __SWAB_64_THRU_32__
   9
  10 static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
  11 {
  12         __asm__("dep %0, 15, 8, %0\n\t"         /* deposit 00ab -> 0bab */
  13                 "shd %%r0, %0, 8, %0"           /* shift 000000ab -> 00ba */
  14                 : "=r" (x)
  15                 : "0" (x));
  16         return x;
  17 }
  18 #define __arch_swab16 __arch_swab16
  19
  20 static inline __attribute_const__ __u32 __arch_swab24(__u32 x)
  21 {
  22         __asm__("shd %0, %0, 8, %0\n\t"         /* shift xabcxabc -> cxab */
  23                 "dep %0, 15, 8, %0\n\t"         /* deposit cxab -> cbab */
  24                 "shd %%r0, %0, 8, %0"           /* shift 0000cbab -> 0cba */
  25                 : "=r" (x)
  26                 : "0" (x));
  27         return x;
  28 }
  29
  30 static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
  31 {
  32         unsigned int temp;
  33         __asm__("shd %0, %0, 16, %1\n\t"        /* shift abcdabcd -> cdab */
  34                 "dep %1, 15, 8, %1\n\t"         /* deposit cdab -> cbab */
  35                 "shd %0, %1, 8, %0"             /* shift abcdcbab -> dcba */
  36                 : "=r" (x), "=&r" (temp)
  37                 : "0" (x));
  38         return x;
  39 }
  40 #define __arch_swab32 __arch_swab32
  41
  42 #if __BITS_PER_LONG > 32
  43 /*
  44 ** From "PA-RISC 2.0 Architecture", HP Professional Books.
  45 ** See Appendix I page 8 , "Endian Byte Swapping".
  46 **
  47 ** Pretty cool algorithm: (* == zero'd bits)
  48 **      PERMH   01234567 -> 67452301 into %0
  49 **      HSHL    67452301 -> 7*5*3*1* into %1
  50 **      HSHR    67452301 -> *6*4*2*0 into %0
  51 **      OR      %0 | %1  -> 76543210 into %0 (all done!)
  52 */
  53 static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
  54 {
  55         __u64 temp;
  56         __asm__("permh,3210 %0, %0\n\t"
  57                 "hshl %0, 8, %1\n\t"
  58                 "hshr,u %0, 8, %0\n\t"
  59                 "or %1, %0, %0"
  60                 : "=r" (x), "=&r" (temp)
  61                 : "0" (x));
  62         return x;
  63 }
  64 #define __arch_swab64 __arch_swab64
  65 #endif /* __BITS_PER_LONG > 32 */
  66
  67 #endif /* _PARISC_SWAB_H */