linux/arch/x86/include/asm/xcr.h

50 lines
1.1 KiB
C

/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright 2008 rPath, Inc. - All Rights Reserved
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2 or (at your
* option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* asm-x86/xcr.h
*
* Definitions for the eXtended Control Register instructions
*/
#ifndef _ASM_X86_XCR_H
#define _ASM_X86_XCR_H
#define XCR_XFEATURE_ENABLED_MASK 0x00000000
#ifdef __KERNEL__
# ifndef __ASSEMBLY__
#include <linux/types.h>
static inline u64 xgetbv(u32 index)
{
u32 eax, edx;
asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */
: "=a" (eax), "=d" (edx)
: "c" (index));
return eax + ((u64)edx << 32);
}
static inline void xsetbv(u32 index, u64 value)
{
u32 eax = value;
u32 edx = value >> 32;
asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */
: : "a" (eax), "d" (edx), "c" (index));
}
# endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_X86_XCR_H */