~ubuntu-branches/ubuntu/precise/linux-lowlatency/precise

1 by Alessio Igor Bogani
Import upstream version 3.2.0
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#ifndef _PARISC_SWAB_H
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#define _PARISC_SWAB_H
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#include <linux/types.h>
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#include <linux/compiler.h>
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#define __SWAB_64_THRU_32__
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static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
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{
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	__asm__("dep %0, 15, 8, %0\n\t"		/* deposit 00ab -> 0bab */
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		"shd %%r0, %0, 8, %0"		/* shift 000000ab -> 00ba */
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		: "=r" (x)
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		: "0" (x));
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	return x;
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}
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#define __arch_swab16 __arch_swab16
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static inline __attribute_const__ __u32 __arch_swab24(__u32 x)
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{
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	__asm__("shd %0, %0, 8, %0\n\t"		/* shift xabcxabc -> cxab */
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		"dep %0, 15, 8, %0\n\t"		/* deposit cxab -> cbab */
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		"shd %%r0, %0, 8, %0"		/* shift 0000cbab -> 0cba */
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		: "=r" (x)
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		: "0" (x));
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	return x;
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}
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static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
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{
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	unsigned int temp;
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	__asm__("shd %0, %0, 16, %1\n\t"	/* shift abcdabcd -> cdab */
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		"dep %1, 15, 8, %1\n\t"		/* deposit cdab -> cbab */
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		"shd %0, %1, 8, %0"		/* shift abcdcbab -> dcba */
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		: "=r" (x), "=&r" (temp)
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		: "0" (x));
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	return x;
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}
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#define __arch_swab32 __arch_swab32
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#if BITS_PER_LONG > 32
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/*
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** From "PA-RISC 2.0 Architecture", HP Professional Books.
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** See Appendix I page 8 , "Endian Byte Swapping".
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**
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** Pretty cool algorithm: (* == zero'd bits)
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**      PERMH   01234567 -> 67452301 into %0
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**      HSHL    67452301 -> 7*5*3*1* into %1
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**      HSHR    67452301 -> *6*4*2*0 into %0
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**      OR      %0 | %1  -> 76543210 into %0 (all done!)
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*/
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static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
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{
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	__u64 temp;
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	__asm__("permh,3210 %0, %0\n\t"
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		"hshl %0, 8, %1\n\t"
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		"hshr,u %0, 8, %0\n\t"
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		"or %1, %0, %0"
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		: "=r" (x), "=&r" (temp)
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		: "0" (x));
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	return x;
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}
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#define __arch_swab64 __arch_swab64
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#endif /* BITS_PER_LONG > 32 */
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#endif /* _PARISC_SWAB_H */