/* $Id: byteorder.h,v 1.5 2008/12/11 12:18:17 ecd Exp $
 */

#ifndef _X49GP_BYTEORDER_H
#define _X49GP_BYTEORDER_H 1

#include <sys/types.h>

static __inline__ uint16_t swab16(uint16_t x)
{
	return ((x & 0xff00) >> 8) |
	       ((x & 0x00ff) << 8);
}

static __inline__ uint32_t swab32(uint32_t x)
{
	return ((x & 0xff000000) >> 24) |
	       ((x & 0x00ff0000) >>  8) |
	       ((x & 0x0000ff00) <<  8) |
	       ((x & 0x000000ff) << 24);
}

#ifdef __sparc__

#define ASI_PL		0x88	/* Primary, implicit, little endian. */

static __inline__ uint16_t __load_le16(const uint16_t *p)
{
	uint16_t x;

	__asm__ __volatile__ ("lduha [%1] %2, %0"
			      : "=r" (x)
			      : "r" (p), "i" (ASI_PL));
	return x;
}

static __inline__ uint32_t __load_le32(const uint32_t *p)
{
	uint32_t x;

	__asm__ __volatile__ ("lduwa [%1] %2, %0"
			      : "=r" (x)
			      : "r" (p), "i" (ASI_PL));
	return x;
}

static __inline__ void __store_le16(uint16_t *p, uint16_t x)
{
	__asm__ __volatile__ ("stha %0, [%1] %2"
			      : /* no outputs */
			      : "r" (x), "r" (p), "i" (ASI_PL));
}

static __inline__ void __store_le32(uint32_t *p, uint32_t x)
{
	__asm__ __volatile__ ("stwa %0, [%1] %2"
			      : /* no outputs */
			      : "r" (x), "r" (p), "i" (ASI_PL));
}

#endif /* __sparc__ */

#if __BYTE_ORDER == __LITTLE_ENDIAN

#define le16_to_cpu(x)	(x)
#define cpu_to_le16(x)	(x)
#define le32_to_cpu(x)	(x)
#define cpu_to_le32(x)	(x)

#define load_le16(p)		(*(p))
#define store_le16(p, x)	(*(p) = (x))
#define load_le32(p)		(*(p))
#define store_le32(p, x)	(*(p) = (x))

#elif __BYTE_ORDER == __BIG_ENDIAN

#define le16_to_cpu(x)	swab16(x)
#define cpu_to_le16(x)	swab16(x)
#define le32_to_cpu(x)	swab32(x)
#define cpu_to_le32(x)	swab32(x)

#define load_le16(p)		__load_le16(p)
#define store_le16(p, x)	__store_le16(p, x)
#define load_le32(p)		__load_le32(p)
#define store_le32(p, x)	__store_le32(p, x)

#else
#error "Cannot determine host byteorder"
#endif

#endif /* !(_X49GP_BYTEORDER_H) */