haiku/headers/private/kernel/arch/x86/64/cpu.h
Paweł Dziepak 4b75a1e237 kernel/x86_64: implement x86_swap_pgdir in C++
No reason not to inline this function.

Signed-off-by: Paweł Dziepak <pdziepak@quarnos.org>
2014-08-25 23:07:29 +02:00

56 lines
1.1 KiB
C

/*
* Copyright 2014, Paweł Dziepak, pdziepak@quarnos.org.
* Distributed under the terms of the MIT License.
*/
#ifndef _KERNEL_ARCH_X86_64_CPU_H
#define _KERNEL_ARCH_X86_64_CPU_H
#include <arch_thread_types.h>
static inline uint64_t
x86_read_msr(uint32_t msr)
{
uint64_t high, low;
asm volatile("rdmsr" : "=a" (low), "=d" (high) : "c" (msr));
return (high << 32) | low;
}
static inline void
x86_write_msr(uint32_t msr, uint64_t value)
{
asm volatile("wrmsr" : : "a" (value) , "d" (value >> 32), "c" (msr));
}
static inline void
x86_context_switch(arch_thread* oldState, arch_thread* newState)
{
asm volatile(
"pushq %%rbp;"
"movq $1f, %c[rip](%0);"
"movq %%rsp, %c[rsp](%0);"
"movq %c[rsp](%1), %%rsp;"
"jmp *%c[rip](%1);"
"1:"
"popq %%rbp;"
:
: "a" (oldState), "d" (newState),
[rsp] "i" (offsetof(arch_thread, current_stack)),
[rip] "i" (offsetof(arch_thread, instruction_pointer))
: "rbx", "rcx", "rdi", "rsi", "r8", "r9", "r10", "r11", "r12", "r13",
"r14", "r15", "memory");
}
static inline void
x86_swap_pgdir(uintptr_t root)
{
asm volatile("movq %0, %%cr3" : : "r" (root));
}
#endif // _KERNEL_ARCH_X86_64_CPU_H