kernel/kernel/kernel.c

   1 #include <tty.h>
   2 #include <io.h>
   3 #include <irq/idt.h>
   4 #include <irq/interrupt.h>
   5 #include <irq/i8259a.h>
   6 #include <stdint.h>
   7 #include <mm/paging.h>
   8 #include <panic.h>
   9
  10 struct idt_descriptor idt[256] __attribute__((aligned(0x10)));
  11 struct idtr idtr __attribute__((aligned(0x10)));
  12 extern void (*_int_handler_table[48])(void);
  13
  14 struct e820_map {
  15         uint64_t base;
  16         uint64_t length;
  17         uint32_t type;
  18         uint32_t attrib;
  19 };
  20
  21 void print_e820(struct e820_map *mmap, int mmap_size)
  22 {
  23         kprint("       Base       |      Length      |   Type   |  Attrib  |\n", 0);
  24         kprint("------------------------------------------------------------\n", 0);
  25         for (int i=0; i<mmap_size; i++) {
  26                 kprintq(mmap[i].base, 1);
  27                 kprintc('|', 0);
  28                 kprintq(mmap[i].length, 1);
  29                 kprintc('|', 0);
  30                 kprintd(mmap[i].type, 1);
  31                 kprintc('|', 0);
  32                 kprintd(mmap[i].attrib, 1);
  33                 kprintc('|', 0);
  34                 kprintc('\n', 0);
  35         }
  36 }
  37
  38 /* Small handler for double faults. Will be put elsewhere eventually. */
  39 int double_fault_handler(struct interrupt_frame *frame)
  40 {
  41         kprint("Double fault occurred!\n", VGA_COLOR_BRIGHT_RED);
  42         kprint("EAX: ", 0);
  43         kprintd(frame->eax, 1);
  44         kprintc(' ', 0);
  45         kprint("EBX: ", 0);
  46         kprintd(frame->ebx, 1);
  47         kprintc(' ', 0);
  48         kprint("ECX: ", 0);
  49         kprintd(frame->ecx, 1);
  50         kprintc(' ', 0);
  51         kprint("EDX: ", 0);
  52         kprintd(frame->edx, 1);
  53         kprintc('\n', 0);
  54         kprint("EBP: ", 0);
  55         kprintd(frame->ebp, 1);
  56         kprintc(' ', 0);
  57         kprint("ESP: ", 0);
  58         kprintd(frame->esp, 1);
  59         kprintc('\n', 0);
  60         kprint("ESI: ", 0);
  61         kprintd(frame->esi, 1);
  62         kprintc(' ', 0);
  63         kprint("EDI: ", 0);
  64         kprintd(frame->edi, 1);
  65         kprintc('\n', 0);
  66         kprint("EIP: ", 0);
  67         kprintd(frame->eip, 1);
  68         kprintc(' ', 0);
  69         kprint("EFLAGS: ", 0);
  70         kprintd(frame->eflags, 1);
  71         kprintc('\n', 0);
  72         PANIC("double fault");
  73 }
  74
  75 void kmain(struct e820_map *mmap, int mmap_size)
  76 {
  77         screen_clear();
  78         kprint("Welcome to Nameless OS!\nRunning revision: ", 0);
  79         kprint(GIT_COMMIT, 0);
  80         kprint("\n", 0);
  81         kprint("BIOS memory map:\n", 0);
  82         print_e820(mmap, mmap_size);
  83         kprint("Preparing IDT...\n", 0);
  84         for (int i=0; i<48; i++) {
  85                 idt_set_descriptor(idt, i, 0x8, _int_handler_table[i], IDT_INTERRUPT_GATE, 0);
  86         }
  87         kprint("IDT prepared, loading...\n", 0);
  88         populate_idtr(&idtr, idt);
  89         load_idt(idtr);
  90         kprint("Setting up interrupts...\n", 0);
  91         register_interrupt(8, &double_fault_handler);
  92         pic_init(0x20, 0x28);
  93         pic_mask_all();
  94         asm volatile ("sti");
  95         kprint("All done\n", 0);
  96         while(1);
  97 }