kernel/kernel.c

   1 #include <tty.h>
   2 #include <io.h>
   3 #include <irq/idt.h>
   4 #include <irq/i8259a.h>
   5 #include <stdint.h>
   6 #include <mm/paging.h>
   7
   8 extern void double_fault(struct abort_frame *frame);
   9 extern void keyb_handler(struct interrupt_frame *frame);
  10 extern void pf_handler(struct fault_frame *frame);
  11 static struct idt_descriptor idt[256] __attribute__((aligned(0x10)));
  12 static struct idtr idtr __attribute__((aligned(0x10)));
  13
  14 static struct page_directory_entry page_dir[1024] __attribute__((aligned(0x1000)));
  15 static struct page_table_entry page_table[1024] __attribute__((aligned(0x1000)));
  16
  17 void kmain(void)
  18 {
  19         screen_clear();
  20         kprint("Welcome to Nameless OS!\nRunning revision: ", 0);
  21         kprint(GIT_COMMIT, 0);
  22         kprint("\nEnabling paging...\n", 0);
  23         for (int i=0xb8; i < 0xc0; i++) {
  24                 page_table[i].p = 1;
  25                 page_table[i].rw = 0;
  26                 page_table[i].us = 0;
  27                 page_table[i].page_frame_addr = i;
  28         }
  29         for (int i=0x100; i < 0x102; i++) {
  30                 page_table[i].p = 1;
  31                 page_table[i].rw = 0;
  32                 page_table[i].us = 0;
  33                 page_table[i].page_frame_addr = i;
  34         }
  35         for (int i=0x102; i < 0x110; i++) {
  36                 page_table[i].p = 1;
  37                 page_table[i].rw = 1;
  38                 page_table[i].us = 0;
  39                 page_table[i].page_frame_addr = i;
  40         }
  41         page_dir[0].p = 1;
  42         page_dir[0].page_table_addr = (int) &page_table >> 12;
  43         enable_paging(page_dir);
  44         kprint("Preparing IDT...\n", 0);
  45         idt_set_descriptor(idt, 8, 0x8, (uint32_t) double_fault, IDT_INTERRUPT_GATE, 0x0);
  46         idt_set_descriptor(idt, 14, 0x8, (uint32_t) pf_handler, IDT_INTERRUPT_GATE, 0x0);
  47         idt_set_descriptor(idt, 33, 0x8, (uint32_t) keyb_handler, IDT_INTERRUPT_GATE, 0x0);
  48         kprint("IDT prepared, loading...\n", 0);
  49         populate_idtr(&idtr, idt);
  50         load_idt(idtr);
  51         kprint("IDT loaded, enabling interrupts...\n", 0);
  52         pic_init(0x20, 0x28);
  53         pic_mask_all();
  54         pic_unmask(1);
  55         asm volatile ("sti");
  56         kprint("All done\n", 0);
  57         struct idtr curr_idtr;
  58         asm ("sidt %0": "=m" (curr_idtr));
  59         kprintw(curr_idtr.limit);
  60         kprintd(curr_idtr.base);
  61         //kprint("Gonna force a double fault\n", 0);
  62         //int test = 1/0;
  63         //int test2 = *(int *) (0xa0000000);
  64         while(1);
  65 }