1/* 2 * Copyright (c) 2012-2013 The Chromium OS Authors. All rights reserved. 3 * 4 * Licensed under the BSD 3-clause. 5 */ 6 7#ifndef __LTP_CPUID_H__ 8#define __LTP_CPUID_H__ 9 10static inline void cpuid(unsigned int info, unsigned int *eax, unsigned int *ebx, 11 unsigned int *ecx, unsigned int *edx) 12{ 13#if defined(__i386__) || defined(__x86_64__) 14 unsigned int _eax = info, _ebx, _ecx, _edx; 15 asm volatile( 16# ifdef __i386__ 17 "xchg %%ebx, %%esi;" /* save ebx (for PIC) */ 18 "cpuid;" 19 "xchg %%esi, %%ebx;" /* restore ebx & pass to caller */ 20 : "=S" (_ebx), 21# else 22 "cpuid;" 23 : "=b" (_ebx), 24# endif 25 "+a" (_eax), "=c" (_ecx), "=d" (_edx) 26 : /* inputs: eax is handled above */ 27 ); 28 if (eax) *eax = _eax; 29 if (ebx) *ebx = _ebx; 30 if (ecx) *ecx = _ecx; 31 if (edx) *edx = _edx; 32#endif 33} 34 35#endif 36