112 lines
2.8 KiB
C
112 lines
2.8 KiB
C
/**
|
|
* @file kernel/arch/x86_64/gdt.c
|
|
* @brief x86-64 GDT
|
|
*
|
|
* @copyright
|
|
* This file is part of ToaruOS and is released under the terms
|
|
* of the NCSA / University of Illinois License - see LICENSE.md
|
|
* Copyright (C) 2021 K. Lange
|
|
*/
|
|
|
|
#include <kernel/printf.h>
|
|
#include <kernel/string.h>
|
|
#include <kernel/process.h>
|
|
|
|
/**
|
|
* @brief 64-bit TSS
|
|
*/
|
|
typedef struct tss_entry {
|
|
uint32_t reserved_0;
|
|
uint64_t rsp[3];
|
|
uint64_t reserved_1;
|
|
uint64_t ist[7];
|
|
uint64_t reserved_2;
|
|
uint16_t reserved_3;
|
|
uint16_t iomap_base;
|
|
} __attribute__ ((packed)) tss_entry_t;
|
|
|
|
typedef struct {
|
|
uint16_t limit_low;
|
|
uint16_t base_low;
|
|
uint8_t base_middle;
|
|
uint8_t access;
|
|
uint8_t granularity;
|
|
uint8_t base_high;
|
|
} __attribute__((packed)) gdt_entry_t;
|
|
|
|
typedef struct {
|
|
uint32_t base_highest;
|
|
uint32_t reserved0;
|
|
} __attribute__((packed)) gdt_entry_high_t;
|
|
|
|
typedef struct {
|
|
uint16_t limit;
|
|
uintptr_t base;
|
|
} __attribute__((packed)) gdt_pointer_t;
|
|
|
|
typedef struct {
|
|
gdt_entry_t entries[6];
|
|
gdt_entry_high_t tss_extra;
|
|
gdt_pointer_t pointer;
|
|
tss_entry_t tss;
|
|
} __attribute__((packed)) __attribute__((aligned(0x10))) FullGDT;
|
|
|
|
FullGDT gdt[32] __attribute__((used)) = {{
|
|
{
|
|
{0x0000, 0x0000, 0x00, 0x00, 0x00, 0x00},
|
|
{0xFFFF, 0x0000, 0x00, 0x9A, (1 << 5) | (1 << 7) | 0x0F, 0x00},
|
|
{0xFFFF, 0x0000, 0x00, 0x92, (1 << 5) | (1 << 7) | 0x0F, 0x00},
|
|
{0xFFFF, 0x0000, 0x00, 0xFA, (1 << 5) | (1 << 7) | 0x0F, 0x00},
|
|
{0xFFFF, 0x0000, 0x00, 0xF2, (1 << 5) | (1 << 7) | 0x0F, 0x00},
|
|
{0x0067, 0x0000, 0x00, 0xE9, 0x00, 0x00},
|
|
},
|
|
{0x00000000, 0x00000000},
|
|
{0x0000, 0x0000000000000000},
|
|
{0,{0,0,0},0,{0,0,0,0,0,0,0},0,0,0},
|
|
}};
|
|
|
|
void gdt_install(void) {
|
|
for (int i = 1; i < 32; ++i) {
|
|
memcpy(&gdt[i], &gdt[0], sizeof(*gdt));
|
|
}
|
|
|
|
for (int i = 0; i < 32; ++i) {
|
|
gdt[i].pointer.limit = sizeof(gdt[i].entries)+sizeof(gdt[i].tss_extra)-1;
|
|
gdt[i].pointer.base = (uintptr_t)&gdt[i].entries;
|
|
|
|
uintptr_t addr = (uintptr_t)&gdt[i].tss;
|
|
gdt[i].entries[5].limit_low = sizeof(gdt[i].tss);
|
|
gdt[i].entries[5].base_low = (addr & 0xFFFF);
|
|
gdt[i].entries[5].base_middle = (addr >> 16) & 0xFF;
|
|
gdt[i].entries[5].base_high = (addr >> 24) & 0xFF;
|
|
gdt[i].tss_extra.base_highest = (addr >> 32) & 0xFFFFFFFF;
|
|
}
|
|
|
|
extern void * stack_top;
|
|
gdt[0].tss.rsp[0] = (uintptr_t)&stack_top;
|
|
|
|
asm volatile (
|
|
"mov %0, %%rdi\n"
|
|
"lgdt (%%rdi)\n"
|
|
"mov $0x10, %%ax\n"
|
|
"mov %%ax, %%ds\n"
|
|
"mov %%ax, %%es\n"
|
|
"mov %%ax, %%ss\n"
|
|
"mov $0x2b, %%ax\n"
|
|
"ltr %%ax\n"
|
|
: : "r"(&gdt[0].pointer)
|
|
);
|
|
}
|
|
|
|
void gdt_copy_to_trampoline(int ap, char * trampoline) {
|
|
memcpy(trampoline, &gdt[ap].pointer, sizeof(gdt[ap].pointer));
|
|
}
|
|
|
|
void arch_set_kernel_stack(uintptr_t stack) {
|
|
gdt[this_core->cpu_id].tss.rsp[0] = stack;
|
|
}
|
|
|
|
void arch_set_tls_base(uintptr_t tlsbase) {
|
|
asm volatile ("wrmsr" : : "c"(0xc0000100), "d"((uint32_t)(tlsbase >> 32)), "a"((uint32_t)(tlsbase & 0xFFFFFFFF)));
|
|
}
|