From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Sun, 29 Jun 2003 12:14:15 -0600
From: Grant Grundler <grundler@parisc-linux.org>
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Subject: [parisc-linux] byte swapping redux
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Hi all,

Can someone explain why include/asm-parisc/byteorder.h uses the following?

#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
#  define __BYTEORDER_HAS_U64__
#  define __SWAB_64_THRU_32__
#endif

vs include/asm-sparc64/byeorder.h:
#define __BYTEORDER_HAS_U64__

I'm pretty sure we don't want __SWAB_64_THRU_32__ defined.
PA-RISC version of ___arch__swab64() is appropriately defined for
both 32 and 64-bit compiles.

For reference include/linux/byteorder/swab.h says:
#ifdef __BYTEORDER_HAS_U64__
static __inline__ __const__ __u64 __fswab64(__u64 x)
{
#  ifdef __SWAB_64_THRU_32__
        __u32 h = x >> 32;
        __u32 l = x & ((1ULL<<32)-1);
        return (((__u64)__swab32(l)) << 32) |
		((__u64)(__swab32(h)));
#  else
        return __arch__swab64(x);
#  endif
}
...

thanks,
grant