1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef PERF_CPUID_H
3#define PERF_CPUID_H 1
4
5
6static inline void
7cpuid(unsigned int op, unsigned int op2, unsigned int *a, unsigned int *b,
8	unsigned int *c, unsigned int *d)
9{
10	/*
11	 * Preserve %ebx/%rbx register by either placing it in %rdi or saving it
12	 * on the stack - x86-64 needs to avoid the stack red zone. In PIC
13	 * compilations %ebx contains the address of the global offset
14	 * table. %rbx is occasionally used to address stack variables in
15	 * presence of dynamic allocas.
16	 */
17	asm(
18#if defined(__x86_64__)
19		"mov %%rbx, %%rdi\n"
20		"cpuid\n"
21		"xchg %%rdi, %%rbx\n"
22#else
23		"pushl %%ebx\n"
24		"cpuid\n"
25		"movl %%ebx, %%edi\n"
26		"popl %%ebx\n"
27#endif
28		: "=a"(*a), "=D"(*b), "=c"(*c), "=d"(*d)
29		: "a"(op), "2"(op2));
30}
31
32void get_cpuid_0(char *vendor, unsigned int *lvl);
33
34#endif
35