Viewing file:  cpuid.h (3.18 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* SPDX-License-Identifier: GPL-2.0 */
/*
* CPUID-related helpers/definitions
*/
#ifndef _ASM_X86_CPUID_H
#define _ASM_X86_CPUID_H
#include <asm/string.h>
struct cpuid_regs {
u32 eax, ebx, ecx, edx;
};
enum cpuid_regs_idx {
CPUID_EAX = 0,
CPUID_EBX,
CPUID_ECX,
CPUID_EDX,
};
#ifdef CONFIG_X86_32
extern int have_cpuid_p(void);
#else
static inline int have_cpuid_p(void)
{
return 1;
}
#endif
static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
/* ecx is often an input as well as an output. */
asm volatile("cpuid"
: "=a" (*eax),
"=b" (*ebx),
"=c" (*ecx),
"=d" (*edx)
: "0" (*eax), "2" (*ecx)
: "memory");
}
#define native_cpuid_reg(reg) \
static inline unsigned int native_cpuid_##reg(unsigned int op) \
{ \
unsigned int eax = op, ebx, ecx = 0, edx; \
\
native_cpuid(&eax, &ebx, &ecx, &edx); \
\
return reg; \
}
/*
* Native CPUID functions returning a single datum.
*/
native_cpuid_reg(eax)
native_cpuid_reg(ebx)
native_cpuid_reg(ecx)
native_cpuid_reg(edx)
#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#define __cpuid native_cpuid
#endif
/*
* Generic CPUID function
* clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
* resulting in stale register contents being returned.
*/
static inline void cpuid(unsigned int op,
unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
*eax = op;
*ecx = 0;
__cpuid(eax, ebx, ecx, edx);
}
/* Some CPUID calls want 'count' to be placed in ecx */
static inline void cpuid_count(unsigned int op, int count,
unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
*eax = op;
*ecx = count;
__cpuid(eax, ebx, ecx, edx);
}
/*
* CPUID functions returning a single datum
*/
static inline unsigned int cpuid_eax(unsigned int op)
{
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return eax;
}
static inline unsigned int cpuid_ebx(unsigned int op)
{
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return ebx;
}
static inline unsigned int cpuid_ecx(unsigned int op)
{
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return ecx;
}
static inline unsigned int cpuid_edx(unsigned int op)
{
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return edx;
}
static __always_inline bool cpuid_function_is_indexed(u32 function)
{
switch (function) {
case 4:
case 7:
case 0xb:
case 0xd:
case 0xf:
case 0x10:
case 0x12:
case 0x14:
case 0x17:
case 0x18:
case 0x1d:
case 0x1e:
case 0x1f:
case 0x8000001d:
return true;
}
return false;
}
#define for_each_possible_hypervisor_cpuid_base(function) \
for (function = 0x40000000; function < 0x40010000; function += 0x100)
static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
{
uint32_t base, eax, signature[3];
for_each_possible_hypervisor_cpuid_base(base) {
cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
if (!memcmp(sig, signature, 12) &&
(leaves == 0 || ((eax - base) >= leaves)))
return base;
}
return 0;
}
#endif /* _ASM_X86_CPUID_H */
|