arch/mips/include/uapi/asm/swab.h

Source file repositories/reference/linux-study-clean/arch/mips/include/uapi/asm/swab.h

File Facts

System
Linux kernel
Corpus path
arch/mips/include/uapi/asm/swab.h
Extension
.h
Size
1532 bytes
Lines
72
Domain
Architecture Layer
Bucket
arch/mips
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _ASM_SWAB_H
#define _ASM_SWAB_H

#include <linux/compiler.h>
#include <linux/types.h>

#define __SWAB_64_THRU_32__

#if !defined(__mips16) &&					\
	((defined(__mips_isa_rev) && (__mips_isa_rev >= 2)) ||	\
	 defined(_MIPS_ARCH_LOONGSON3A))

static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
{
	__asm__(
	"	.set	push			\n"
	"	.set	arch=mips32r2		\n"
	"	wsbh	%0, %1			\n"
	"	.set	pop			\n"
	: "=r" (x)
	: "r" (x));

	return x;
}
#define __arch_swab16 __arch_swab16

static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
{
	__asm__(
	"	.set	push			\n"
	"	.set	arch=mips32r2		\n"
	"	wsbh	%0, %1			\n"
	"	rotr	%0, %0, 16		\n"
	"	.set	pop			\n"
	: "=r" (x)
	: "r" (x));

	return x;
}
#define __arch_swab32 __arch_swab32

/*
 * Having already checked for MIPS R2, enable the optimized version for
 * 64-bit kernel on r2 CPUs.
 */
#ifdef __mips64
static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
{
	__asm__(
	"	.set	push			\n"
	"	.set	arch=mips64r2		\n"
	"	dsbh	%0, %1			\n"
	"	dshd	%0, %0			\n"
	"	.set	pop			\n"
	: "=r" (x)
	: "r" (x));

	return x;
}
#define __arch_swab64 __arch_swab64
#endif /* __mips64 */
#endif /* (not __mips16) and (MIPS R2 or newer or Loongson 3A) */
#endif /* _ASM_SWAB_H */

Annotation

Implementation Notes