u-boot/arch/m68k/include/asm/byteorder.h
Angelo Dureghello faae49543a m68k: fix multiple memory accesses on swap operations
On a
	u32 val = __sw32(*addr);

multiple memory accesses are not welcome, since "addr" may
be an IO peripheral register address.
This patch changes __sw16/32 to perform a single memory
access for the source value.

Signed-off-by: Angelo Dureghello <angelo@sysam.it>
2018-09-16 00:01:13 +02:00

96 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) 2004-2007 Freescale Semiconductor, Inc.
* TsiChung Liew (Tsi-Chung.Liew@freescale.com)
*/
#ifndef _M68K_BYTEORDER_H
#define _M68K_BYTEORDER_H
#include <asm/types.h>
#ifdef __GNUC__
static inline __u32 __sw32(__u32 x)
{
__u32 v = x;
return v << 24 |
(v & (__u32)0x0000ff00UL) << 8 |
(v & (__u32)0x00ff0000UL) >> 8 |
v >> 24;
}
static inline __u16 __sw16(__u16 x)
{
__u16 v = x;
return (v & (__u16)0x00ffU) << 8 |
(v & (__u16)0xff00U) >> 8;
}
static __inline__ unsigned ld_le16(const volatile unsigned short *addr)
{
return __sw16(*addr);
}
static __inline__ void st_le16(volatile unsigned short *addr,
const unsigned val)
{
*addr = __sw16(val);
}
static __inline__ unsigned ld_le32(const volatile unsigned *addr)
{
return __sw32(*addr);
}
static __inline__ void st_le32(volatile unsigned *addr, const unsigned val)
{
*addr = __sw32(val);
}
#if 0
/* alas, egcs sounds like it has a bug in this code that doesn't use the
inline asm correctly, and can cause file corruption. Until I hear that
it's fixed, I can live without the extra speed. I hope. */
#if !(__GNUC__ >= 2 && __GNUC_MINOR__ >= 90)
#if 0
# define __arch_swab16(x) ld_le16(&x)
# define __arch_swab32(x) ld_le32(&x)
#else
static __inline__ __attribute__ ((const))
__u16 ___arch__swab16(__u16 value)
{
return __sw16(value);
}
static __inline__ __attribute__ ((const))
__u32 ___arch__swab32(__u32 value)
{
return __sw32(value);
}
#define __arch__swab32(x) ___arch__swab32(x)
#define __arch__swab16(x) ___arch__swab16(x)
#endif /* 0 */
#endif
/* The same, but returns converted value from the location pointer by addr. */
#define __arch__swab16p(addr) ld_le16(addr)
#define __arch__swab32p(addr) ld_le32(addr)
/* The same, but do the conversion in situ, ie. put the value back to addr. */
#define __arch__swab16s(addr) st_le16(addr,*addr)
#define __arch__swab32s(addr) st_le32(addr,*addr)
#endif
#endif /* __GNUC__ */
#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
#define __BYTEORDER_HAS_U64__
#endif
#include <linux/byteorder/big_endian.h>
#endif /* _M68K_BYTEORDER_H */