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
   9 struct idt_descriptor idt[256] __attribute__((aligned(0x10)));
  10 struct idtr idtr __attribute__((aligned(0x10)));
  11 extern void (*_int_handler_table[48])(void);
  12
  13 struct e820_map {
  14         uint64_t base;
  15         uint64_t length;
  16         uint32_t type;
  17         uint32_t attrib;
  18 };
  19
  20 void print_e820(struct e820_map *mmap, int mmap_size)
  21 {
  22         kprint("       Base       |      Length      |   Type   |  Attrib  |\n", 0);
  23         kprint("------------------------------------------------------------\n", 0);
  24         for (int i=0; i<mmap_size; i++) {
  25                 kprintq(mmap[i].base);
  26                 kprintc('|', 0);
  27                 kprintq(mmap[i].length);
  28                 kprintc('|', 0);
  29                 kprintd(mmap[i].type);
  30                 kprintc('|', 0);
  31                 kprintd(mmap[i].attrib);
  32                 kprintc('|', 0);
  33                 kprintc('\n', 0);
  34         }
  35 }
  36
  37 /* Small handler for double faults. Will be put elsewhere eventually. */
  38 int double_fault_handler(struct interrupt_frame *frame)
  39 {
  40         kprint("PANIC: Double fault occurred!\n", VGA_COLOR_BRIGHT_RED);
  41         kprint("EAX: ", VGA_COLOR_BRIGHT_RED);
  42         kprintd(frame->eax);
  43         kprint("\n", VGA_COLOR_BRIGHT_RED);
  44         kprint("EBX: ", VGA_COLOR_BRIGHT_RED);
  45         kprintd(frame->ebx);
  46         kprint("\n", VGA_COLOR_BRIGHT_RED);
  47         kprint("ECX: ", VGA_COLOR_BRIGHT_RED);
  48         kprintd(frame->ecx);
  49         kprint("\n", VGA_COLOR_BRIGHT_RED);
  50         kprint("EDX: ", VGA_COLOR_BRIGHT_RED);
  51         kprintd(frame->edx);
  52         kprint("\n", VGA_COLOR_BRIGHT_RED);
  53         kprint("EBP: ", VGA_COLOR_BRIGHT_RED);
  54         kprintd(frame->ebp);
  55         kprint("\n", VGA_COLOR_BRIGHT_RED);
  56         kprint("ESP: ", VGA_COLOR_BRIGHT_RED);
  57         kprintd(frame->esp);
  58         kprint("\n", VGA_COLOR_BRIGHT_RED);
  59         kprint("ESI: ", VGA_COLOR_BRIGHT_RED);
  60         kprintd(frame->esi);
  61         kprint("\n", VGA_COLOR_BRIGHT_RED);
  62         kprint("EDI: ", VGA_COLOR_BRIGHT_RED);
  63         kprintd(frame->edi);
  64         kprint("\n", VGA_COLOR_BRIGHT_RED);
  65         kprint("EIP: ", VGA_COLOR_BRIGHT_RED);
  66         kprintd(frame->eip);
  67         kprint("\n", VGA_COLOR_BRIGHT_RED);
  68         kprint("EFLAGS: ", VGA_COLOR_BRIGHT_RED);
  69         kprintd(frame->eflags);
  70         kprint("\n", VGA_COLOR_BRIGHT_RED);
  71
  72         /* IF has already been cleared for us */
  73         asm("cli");
  74 halt:
  75         asm("hlt");
  76         goto halt;
  77 }
  78
  79 void kmain(struct e820_map *mmap, int mmap_size)
  80 {
  81         screen_clear();
  82         kprint("Welcome to Nameless OS!\nRunning revision: ", 0);
  83         kprint(GIT_COMMIT, 0);
  84         kprint("\n", 0);
  85         kprint("BIOS memory map:\n", 0);
  86         print_e820(mmap, mmap_size);
  87         kprint("Preparing IDT...\n", 0);
  88         for (int i=0; i<48; i++) {
  89                 idt_set_descriptor(idt, i, 0x8, _int_handler_table[i], IDT_INTERRUPT_GATE, 0);
  90         }
  91         kprint("IDT prepared, loading...\n", 0);
  92         populate_idtr(&idtr, idt);
  93         load_idt(idtr);
  94         kprint("Setting up interrupts...\n", 0);
  95         register_interrupt(8, &double_fault_handler);
  96         pic_init(0x20, 0x28);
  97         pic_mask_all();
  98         asm volatile ("sti");
  99         kprint("All done\n", 0);
 100         while(1);
 101 }