From 578d467b80015c52d0c96c8443b4c13936f33365 Mon Sep 17 00:00:00 2001
From: Aleksa Vučković <aleksav013@gmail.com>
Date: Mon, 11 Oct 2021 11:35:59 +0200
Subject: (IDT + keyboard) finally working

---
 src/kernel.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 69 insertions(+), 17 deletions(-)

(limited to 'src/kernel.c')

diff --git a/src/kernel.c b/src/kernel.c
index c6d1045..0882580 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -6,6 +6,17 @@
 static const size_t VGA_WIDTH = 80;
 static const size_t VGA_HEIGHT = 25;
 
+#define PIC1_COMMAND_PORT 0x20
+#define PIC1_DATA_PORT 0x21
+#define PIC2_COMMAND_PORT 0xA0
+#define PIC2_DATA_PORT 0xA1
+// IO Ports for Keyboard
+#define KEYBOARD_DATA_PORT 0x60
+#define KEYBOARD_STATUS_PORT 0x64
+
+extern char ioport_in(uint8_t port);
+extern void ioport_out(uint8_t port, char data);
+
 static inline uint8_t vga_entry_color(enum vga_color fg, enum vga_color bg) 
 {
     return fg | bg << 4;
@@ -23,24 +34,24 @@ uint16_t* terminal_buffer;
  
 void terminal_initialize(void) 
 {
-    terminal_row = 0;
-    terminal_column = 0;
-    terminal_color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
-    terminal_buffer = (uint16_t*) 0xB8000;
-    for (size_t y = 0; y < VGA_HEIGHT; y++)
+    terminal_row=0;
+    terminal_column=0;
+    terminal_color=vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
+    terminal_buffer=(uint16_t*) 0xB8000;
+    for(size_t y=0;y<VGA_HEIGHT;y++)
     {
-	for (size_t x = 0; x < VGA_WIDTH; x++)
+	for(size_t x=0;x<VGA_WIDTH;x++)
 	{
-	    const size_t index = y * VGA_WIDTH + x;
-	    terminal_buffer[index] = vga_entry(' ', terminal_color);
+	    const size_t index=y*VGA_WIDTH+x;
+	    terminal_buffer[index]=vga_entry(' ', terminal_color);
 	}
     }
 }
  
 void terminal_putentryat(char c, uint8_t color, size_t x, size_t y) 
 {
-    const size_t index = y * VGA_WIDTH + x;
-    terminal_buffer[index] = vga_entry(c, color);
+    const size_t index=y*VGA_WIDTH+x;
+    terminal_buffer[index]=vga_entry(c, color);
 }
 
 void movescreen()
@@ -55,9 +66,9 @@ void terminal_putchar(char c)
     else
     {
 	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
-	if (++terminal_column == VGA_WIDTH) terminal_column = 0,terminal_row++;
+	if (++terminal_column==VGA_WIDTH) terminal_column=0,terminal_row++;
     }
-    if (terminal_row == VGA_HEIGHT) movescreen();
+    if (terminal_row==VGA_HEIGHT) movescreen();
 }
  
 void terminal_writestring(const char* data) 
@@ -65,13 +76,54 @@ void terminal_writestring(const char* data)
     for(int i=0;data[i]!='\0';i++) terminal_putchar(data[i]);
 }
 
-void kernel_main(void) 
+void init_keyboard()
 {
-    terminal_initialize();
+    // 0xFD = 1111 1101 in binary. enables only IRQ1
+    // Why IRQ1? Remember, IRQ0 exists, it's 0-based
+    ioport_out(PIC1_DATA_PORT, 0xFD);
+}
+
+#include"keyboard.h"
+void handle_keyboard_interrupt()
+{
+    // Write end of interrupt (EOI)
+    ioport_out(PIC1_COMMAND_PORT, 0x20);
+    unsigned char status = ioport_in(KEYBOARD_STATUS_PORT);
+
+    // Lowest bit of status will be set if buffer not empty
+    // (thanks mkeykernel)
+    if (status & 0x1)
+    {
+	char keycode = ioport_in(KEYBOARD_DATA_PORT);
+	if (keycode < 0 || (uint8_t)keycode >= 128) return;
+
+	if(keycode==14)
+	{
+	    if(terminal_column) terminal_column--;
+	    terminal_putchar(keyboard[keycode]);
+	    terminal_column--;
+	    return;
+	}
 
-   for(size_t i=0;i<50;i++)
-   {
+	terminal_putchar(keyboard[keycode]);
+
+    }
+}
+void print_message()
+{
+    for(size_t i=0;i<50;i++)
+    {
        for(size_t j=0;j<i;j++) terminal_writestring("#");
        terminal_writestring("Hello, kernel World!\n");
-   }
+    }
+}
+
+void kernel_main(void)
+{
+    terminal_initialize();
+    print_message();
+    init_idt_table();
+    init_keyboard();
+    terminal_writestring("First part is working\n");
+    while(1);
 }
-- 
cgit v1.2.3