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linux/arch/s390/include/asm/swab.h
Martin Schwidefsky 987bcdacb1 [S390] use inline assembly contraints available with gcc 3.3.3
Drop support to compile the kernel with gcc versions older than 3.3.3.
This allows us to use the "Q" inline assembly contraint on some more
inline assemblies without duplicating a lot of complex code (e.g. __xchg
and __cmpxchg). The distinction for older gcc versions can be removed
which saves a few lines and simplifies the code.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00

92 lines
1.7 KiB
C

#ifndef _S390_SWAB_H
#define _S390_SWAB_H
/*
* include/asm-s390/swab.h
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/types.h>
#ifndef __s390x__
# define __SWAB_64_THRU_32__
#endif
#ifdef __s390x__
static inline __u64 __arch_swab64p(const __u64 *x)
{
__u64 result;
asm volatile("lrvg %0,%1" : "=d" (result) : "m" (*x));
return result;
}
#define __arch_swab64p __arch_swab64p
static inline __u64 __arch_swab64(__u64 x)
{
__u64 result;
asm volatile("lrvgr %0,%1" : "=d" (result) : "d" (x));
return result;
}
#define __arch_swab64 __arch_swab64
static inline void __arch_swab64s(__u64 *x)
{
*x = __arch_swab64p(x);
}
#define __arch_swab64s __arch_swab64s
#endif /* __s390x__ */
static inline __u32 __arch_swab32p(const __u32 *x)
{
__u32 result;
asm volatile(
#ifndef __s390x__
" icm %0,8,%O1+3(%R1)\n"
" icm %0,4,%O1+2(%R1)\n"
" icm %0,2,%O1+1(%R1)\n"
" ic %0,%1"
: "=&d" (result) : "Q" (*x) : "cc");
#else /* __s390x__ */
" lrv %0,%1"
: "=d" (result) : "m" (*x));
#endif /* __s390x__ */
return result;
}
#define __arch_swab32p __arch_swab32p
#ifdef __s390x__
static inline __u32 __arch_swab32(__u32 x)
{
__u32 result;
asm volatile("lrvr %0,%1" : "=d" (result) : "d" (x));
return result;
}
#define __arch_swab32 __arch_swab32
#endif /* __s390x__ */
static inline __u16 __arch_swab16p(const __u16 *x)
{
__u16 result;
asm volatile(
#ifndef __s390x__
" icm %0,2,%O+1(%R1)\n"
" ic %0,%1\n"
: "=&d" (result) : "Q" (*x) : "cc");
#else /* __s390x__ */
" lrvh %0,%1"
: "=d" (result) : "m" (*x));
#endif /* __s390x__ */
return result;
}
#define __arch_swab16p __arch_swab16p
#endif /* _S390_SWAB_H */