ROSE/kernel.c

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2.8 KiB
C
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#include <stdint.h>
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#include "print.h"
#include "interrupt.h"
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#include "tss.c"
typedef unsigned short word;
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char check_apic() {
uint32_t eax, ebx, ecx, edx;
asm("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) : "a"(1));
return (edx & (1 << 9)) != 0;
}
char check_sse() {
uint32_t eax, ebx, ecx, edx;
asm("cpuid" : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) : "a"(1));
return (edx & (1 << 25)) != 0;
}
void enable_sse() {
asm volatile(
"mov %%cr0, %%eax\n"
"and $0xFFFB, %%ax\n"
"or $0x2, %%ax\n"
"mov %%eax, %%cr0\n"
"mov %%cr4, %%eax\n"
"or $0x600, %%ax\n"
"mov %%eax, %%cr4\n"
: : : "%eax"
);
}
void print_flags() {
uint32_t flags;
asm volatile("pushfd\npop %%eax":"=a"(flags));
printDword(flags, 0xB8000 + (160*4) + 50);
}
void print_cr0() {
uint32_t reg;
asm volatile("mov %%cr0, %%eax":"=a"(reg));
printDword(reg, 0xB8000 + (160*5) + 50);
}
void print_cr3() {
uint32_t reg;
asm volatile("mov %%cr3, %%eax":"=a"(reg));
printDword(reg, 0xB8000 + (160*5) + 50 + 8*2 + 2);
}
void print_cr4() {
uint32_t reg;
asm volatile("mov %%cr4, %%eax":"=a"(reg));
printDword(reg, 0xB8000 + (160*5) + 50 + 8*4 + 4);
}
extern void enter_v86(uint32_t ss, uint32_t esp, uint32_t cs, uint32_t eip);
extern void v86Code();
extern void jmp_usermode_test();
/*
Real Mode Accessible (First MB)
00000 - 02000 IVT
01000 - 04000 Paging
04000 - 07C00 Free
07C00 - 08000 Boot
08000 - 20000 Kernel Code
20000 - 22080 TSS
80000 - 90000 Real Mode Stack
90000 - A0000 Free
A0000 - FFFFF BIOS Area
Protected Only (1MB+)
100000 - Free
*/
void start() {
word *vga_text = (word *)0xb8000;
char h[] = "LuciaOS";
for (int i = 0; i < sizeof(h); i++)
*(char *)&vga_text[i] = h[i];
uint32_t o;
asm("mov %%esp, %%eax" : "=a"(o) : :);
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printDword(o, (uint16_t *)&vga_text[80]);
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asm("mov %%ebp, %%eax" : "=a"(o) : :);
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printDword(o, (uint16_t *)&vga_text[160]);
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//char c[] = "APIC support: ";
//char apic;
//printByte(apic = check_apic(), (short*)&vga_text[80*3 + sizeof(c) - 1]);
//for (int i = 0; i < sizeof(c); i++)
// *(char *)&vga_text[i+(80*3)] = c[i];
//if (!apic) return;
char sse_str[] = "SSE support: ";
char sse;
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printByte(sse = check_sse(), (uint16_t*)&vga_text[80*4 + sizeof(sse_str) - 1]);
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for (int i = 0; i < sizeof(sse_str); i++)
*(char *)&vga_text[i+(80*4)] = sse_str[i];
if (!sse) return;
enable_sse();
// edit
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setup_interrupts();
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setup_tss();
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print_flags();
print_cr0();
print_cr3();
print_cr4();
FARPTR v86_entry = i386LinearToFp(v86Code);
enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry));
//jmp_usermode_test();
}