diff options
author | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
commit | 7203781c98ad9147564d327de6f6513ad8fc0f4e (patch) | |
tree | 5c29a2a04a626bf08a0d56fd8a0068b3c92ad284 /arch/alpha/include/asm/byteorder.h | |
parent | 671eef85a3e885dff4ce210d8774ad50a91d5967 (diff) | |
parent | af2e1f276ff08f17192411ea3b71c13a758dfe12 (diff) |
Merge branch 'x86/cpu' into x86/core
Conflicts:
arch/x86/kernel/cpu/feature_names.c
include/asm-x86/cpufeature.h
Diffstat (limited to 'arch/alpha/include/asm/byteorder.h')
-rw-r--r-- | arch/alpha/include/asm/byteorder.h | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/byteorder.h b/arch/alpha/include/asm/byteorder.h new file mode 100644 index 00000000000..58e958fc7f1 --- /dev/null +++ b/arch/alpha/include/asm/byteorder.h @@ -0,0 +1,47 @@ +#ifndef _ALPHA_BYTEORDER_H +#define _ALPHA_BYTEORDER_H + +#include <asm/types.h> +#include <linux/compiler.h> +#include <asm/compiler.h> + +#ifdef __GNUC__ + +static inline __attribute_const__ __u32 __arch__swab32(__u32 x) +{ + /* + * Unfortunately, we can't use the 6 instruction sequence + * on ev6 since the latency of the UNPKBW is 3, which is + * pretty hard to hide. Just in case a future implementation + * has a lower latency, here's the sequence (also by Mike Burrows) + * + * UNPKBW a0, v0 v0: 00AA00BB00CC00DD + * SLL v0, 24, a0 a0: BB00CC00DD000000 + * BIS v0, a0, a0 a0: BBAACCBBDDCC00DD + * EXTWL a0, 6, v0 v0: 000000000000BBAA + * ZAP a0, 0xf3, a0 a0: 00000000DDCC0000 + * ADDL a0, v0, v0 v0: ssssssssDDCCBBAA + */ + + __u64 t0, t1, t2, t3; + + t0 = __kernel_inslh(x, 7); /* t0 : 0000000000AABBCC */ + t1 = __kernel_inswl(x, 3); /* t1 : 000000CCDD000000 */ + t1 |= t0; /* t1 : 000000CCDDAABBCC */ + t2 = t1 >> 16; /* t2 : 0000000000CCDDAA */ + t0 = t1 & 0xFF00FF00; /* t0 : 00000000DD00BB00 */ + t3 = t2 & 0x00FF00FF; /* t3 : 0000000000CC00AA */ + t1 = t0 + t3; /* t1 : ssssssssDDCCBBAA */ + + return t1; +} + +#define __arch__swab32 __arch__swab32 + +#endif /* __GNUC__ */ + +#define __BYTEORDER_HAS_U64__ + +#include <linux/byteorder/little_endian.h> + +#endif /* _ALPHA_BYTEORDER_H */ |