Timer interrupt seems to work

Default settings on PIT, but maybe will want to mess with them later

rust_experiments/src/lib.rs

@@ -24,6 +24,16 @@ pub extern fn rust_handle_keyboard() {
     checkerboard(vga_buffer::Color::Green);
 }
 
+#[no_mangle]
+pub extern fn rust_handle_timer() {
+    let color_code = vga_buffer::ColorCode::new(vga_buffer::Color::Black,
+                                          vga_buffer::Color::White);
+
+
+    vga_buffer::write_to_coord(40, 1, b'X', color_code);
+
+}
+
 #[no_mangle]
 pub extern fn rust_main() {
     clear();

rust_experiments/src/long_mode_init.asm

@@ -4,6 +4,7 @@ global get_rdtsc
 global call_interrupt
 extern rust_interrupt_handler
 extern rust_handle_keyboard
+extern rust_handle_timer
 
 section .text
 bits 64
@@ -12,6 +13,7 @@ long_mode_start:
     ; print "OKAY"
     call setup_SSE
     call setup_IDT
+    call setup_PIT
     call setup_PIC
     extern rust_main
     call rust_main
@@ -113,9 +115,46 @@ handle_keyboard:
 
     iretq
 
-%define int_num 9
+handle_timer:
+    push rax
+    push rcx
+    push rdx
+    push r8
+    push r9
+    push r10
+    push r11
+    pushfq
+
+    call rust_handle_timer
+
+    mov al, END_OF_INTERRUPT
+    out PIC1_COMMAND, al
+    out PIC2_COMMAND, al
+
+    popfq
+    pop r11
+    pop r10
+    pop r9
+    pop r8
+    pop rdx
+    pop rcx
+    pop rax
+    iretq
+
 setup_IDT:
     lidt [idt64.pointer]
+    %define timer_int 8
+    mov rax, handle_timer
+    mov [idt64 + timer_int*16], ax
+    mov word [idt64 + timer_int*16 + 2], cs
+    mov word [idt64 + timer_int*16 + 4], 0x8e00
+    shr rax, 16
+    mov [idt64 + timer_int*16 + 6], ax
+    shr rax, 16
+    mov [idt64 + timer_int*16 + 8], eax
+
+
+    %define int_num 9
     mov rax, handle_keyboard
     mov [idt64 + int_num*16], ax
     mov word [idt64 + int_num*16 +2], cs
@@ -123,17 +162,21 @@ setup_IDT:
     shr rax, 16
     mov [idt64 + int_num*16 + 6], ax
     shr rax, 16
-    mov [idt64 + int_num*16 + 8], ax
+    mov [idt64 + int_num*16 + 8], eax
+
     ret
 
 setup_PIC:
-    mov al, 0xfd
+    mov al, 0xfc
     out byte 0x21, al
     mov al, 0xff
     out byte 0xa1, al
     sti
     ret
 
+setup_PIT:
+    ret
+
 idt64:
     resb 50*16
 .pointer: