msr.h

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/*
 * Copyright (c) 2019 Intel Corp.
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_ARCH_X86_MSR_H_
#define ZEPHYR_INCLUDE_ARCH_X86_MSR_H_
 
/*
 * Model specific registers (MSR).  Access with z_x86_msr_read/write().
 */
 
#define X86_TIME_STAMP_COUNTER_MSR      0x00000010
 
#define X86_SPEC_CTRL_MSR               0x00000048
#define X86_SPEC_CTRL_MSR_IBRS          BIT(0)
#define X86_SPEC_CTRL_MSR_SSBD          BIT(2)
 
#define X86_APIC_BASE_MSR               0x0000001b
#define X86_APIC_BASE_MSR_X2APIC        BIT(10)
 
#define X86_MTRR_DEF_TYPE_MSR           0x000002ff
#define X86_MTRR_DEF_TYPE_MSR_ENABLE    BIT(11)
 
#define X86_X2APIC_BASE_MSR             0x00000800 /* .. thru 0x00000BFF */
 
#define X86_EFER_MSR                    0xC0000080U
#define X86_EFER_MSR_SCE                BIT(0)
#define X86_EFER_MSR_LME                BIT(8)
#define X86_EFER_MSR_NXE                BIT(11)
 
/* STAR 31:0   Unused in long mode
 *      47:32  Kernel CS (SS = CS+8)
 *      63:48  User CS (SS = CS+8)
 */
#define X86_STAR_MSR                    0xC0000081U
 
/* Location for system call entry point */
#define X86_LSTAR_MSR                   0xC0000082U
 
/* Low 32 bits in this MSR are the SYSCALL mask applied to EFLAGS */
#define X86_FMASK_MSR                   0xC0000084U
 
#define X86_FS_BASE                     0xC0000100U
#define X86_GS_BASE                     0xC0000101U
#define X86_KERNEL_GS_BASE              0xC0000102U
 
#ifndef _ASMLANGUAGE
#ifdef __cplusplus
extern "C" {
#endif
 
/*
 * z_x86_msr_write() is shared between 32- and 64-bit implementations, but
 * due to ABI differences with long return values, z_x86_msr_read() is not.
 */
 
static inline void z_x86_msr_write(unsigned int msr, uint64_t data)
{
        uint32_t high = data >> 32;
        uint32_t low = data & 0xFFFFFFFFU;
 
        __asm__ volatile ("wrmsr" : : "c"(msr), "a"(low), "d"(high));
}
 
#ifdef CONFIG_X86_64
 
static inline uint64_t z_x86_msr_read(unsigned int msr)
{
        union {
                struct {
                        uint32_t lo;
                        uint32_t hi;
                };
                uint64_t value;
        } rv;
 
        __asm__ volatile ("rdmsr" : "=a" (rv.lo), "=d" (rv.hi) : "c" (msr));
 
        return rv.value;
}
 
#else
 
static inline uint64_t z_x86_msr_read(unsigned int msr)
{
        uint64_t ret;
 
        __asm__ volatile("rdmsr" : "=A" (ret) : "c" (msr));
 
        return ret;
}
 
#endif
 
#ifdef __cplusplus
}
#endif
#endif /* _ASMLANGUAGE */
 
#endif /* ZEPHYR_INCLUDE_ARCH_X86_MSR_H_ */