some work on keyboard initialization

5 files changed, 99 insertions, 7 deletions

diff --git a/doc/LINKS.TODO b/doc/LINKS.TODO
index 53cc093..daf9016 100644
--- a/doc/LINKS.TODO
+++ b/doc/LINKS.TODO
@@ -43,4 +43,7 @@ http://wiki.osdev.org/8259_PIC
 
 keyboard:
 http://wiki.osdev.org/"8042"_PS/2_Controller
+https://www.lowlevel.eu/wiki/Keyboard_Controller
 
+PIT:
+http://wiki.osdev.org/Programmable_Interval_Timer
diff --git a/src/Makefile b/src/Makefile
index 14aa939..d72f5aa 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -13,10 +13,10 @@ all: image.bin kernel.sym
 # + M * 512 (M is currently 7) = 3144 for kernel.bin
 # + 1 * 512 = 512 for magic.bin
 # (M + N + 1 is the number of sectors to be read in stage 2, as stage 1
-# loads only the first sector, so adapt NOF_LOAD_SECTORS to 20)
+# loads only the first sector, so adapt NOF_LOAD_SECTORS to 21)
 image.bin: boot.bin kernel.bin magic.bin
 	cat boot.bin kernel.bin > image.tmp
-	truncate -s 10240 image.tmp
+	truncate -s 10752 image.tmp
 	cat image.tmp magic.bin > image.bin
 	
 boot.bin: boot.asm boot_gdt.asm stage1_functions.asm stage2_functions.asm stage2_switch_mode.asm stage2_a20.asm
diff --git a/src/kernel.c b/src/kernel.c
index 732151e..d4dba01 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -36,6 +36,7 @@ void entry( void )
 	interrupt_t interrupt;
 	interrupts_init( &interrupt );
 	
+	puts( "Initializing PS/2 keyboard" );
 	keyboard_t keyboard;
 	keyboard_init( &keyboard );
 	interrupt_handler_t keyboard_interrupt_handler;
diff --git a/src/keyboard.c b/src/keyboard.c
index f89332c..c591c6a 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1,7 +1,62 @@
+#include <stdbool.h>
+
 #include "keyboard.h"
 
 #include "stdio.h"
 
+// status register on command port (read)
+#define STATUS_REG_OUTPUT_BUF_FULL 0x01
+#define STATUS_REG_INPUT_BUF_FULL 0x02
+
+// generic PS/2 commands
+#define COMMAND_GET_STATE 0x20
+#define COMMAND_SET_STATE 0x60
+#define COMMAND_DISABLE_PORT1 0xAD 
+#define COMMAND_ENABLE_PORT1 0xAE 
+
+// keyboard specific commands, PSAUX1
+#define KBD_COMMAND_SET_LEDS 0xED
+#define KBD_SET_SCANCODE 0xF0
+#define KBD_ACTIVATE 0xF4
+
+#define STATUS_CONTROL_CONFIG_ENABLE_IRQ_PORT1 0x01
+#define STATUS_CONTROL_CONFIG_CLOCK_PORT1 0x10
+
+// keyboard LED status codes
+#define KBD_LED_SCROLL_LOCK_ON 0x01
+#define KBD_LED_NUM_LOCK_ON 0x02
+#define KBD_LED_CAPS_LOCK_ON 0x04
+#define KBD_LED_ALL_OFF 0x00
+#define KBD_LED_ALL_ON KBD_LED_SCROLL_LOCK_ON | KBD_LED_NUM_LOCK_ON | KBD_LED_CAPS_LOCK_ON
+
+// keyboard scan codes
+#define KBD_SCANCODE_1 0x01
+#define KBD_SCANCODE_2 0x02
+#define KBD_SCANCODE_3 0x03
+
+static bool has_data( keyboard_t *keyboard )
+{
+	return ( port8_read( &keyboard->command_port ) & STATUS_REG_OUTPUT_BUF_FULL ) == STATUS_REG_OUTPUT_BUF_FULL;
+}
+
+static uint8_t read_data( keyboard_t *keyboard )
+{
+	while( ( port8_read( &keyboard->command_port ) & STATUS_REG_OUTPUT_BUF_FULL ) == 0 ) { }
+	return port8_read( &keyboard->data_port );
+}
+
+static void send_command( keyboard_t *keyboard, uint8_t command )
+{
+	while( port8_read( &keyboard->command_port ) & STATUS_REG_INPUT_BUF_FULL ) { }
+	port8_write( &keyboard->command_port, command );
+}
+
+static void write_data( keyboard_t *keyboard, uint8_t data )
+{
+	while( port8_read( &keyboard->command_port ) & STATUS_REG_INPUT_BUF_FULL ) { }
+	port8_write( &keyboard->data_port, data );
+}
+
 void keyboard_init( keyboard_t *keyboard )
 {
 	memset( keyboard, 0, sizeof( keyboard_t ) );
@@ -9,14 +64,47 @@ void keyboard_init( keyboard_t *keyboard )
 	port8_init( &keyboard->command_port, 0x64 );
 	port8_init( &keyboard->data_port, 0x60 );
 	
+	// first switch off port 1
+	send_command( keyboard, COMMAND_DISABLE_PORT1 );
+	
+	// consume character pressed before executing the kernel
+	while( port8_read( &keyboard->command_port ) & STATUS_REG_OUTPUT_BUF_FULL ) {
+		port8_read( &keyboard->data_port );
+	}
+	
+	// enable port 1
+	send_command( keyboard, COMMAND_ENABLE_PORT1 );
+	
+	// enable interrupts for port 1
+	send_command( keyboard, COMMAND_GET_STATE );
+	uint8_t status = read_data( keyboard );
+	status |= STATUS_CONTROL_CONFIG_ENABLE_IRQ_PORT1;
+	status &= ~STATUS_CONTROL_CONFIG_CLOCK_PORT1;
+	send_command( keyboard, COMMAND_SET_STATE );
+	write_data( keyboard, status );
+	
+	// disable all LEDs on keyboard
+	//~ send_command( keyboard, KBD_COMMAND_SET_LEDS );
+	//~ write_data( keyboard, KBD_LED_ALL_ON );
+	
+	// set scan code
+	//~ send_command( keyboard, KBD_SET_SCANCODE );
+	//~ write_data( keyboard, KBD_SCANCODE_2 );
+	
+	// activate keyboard
+	//~ send_command( keyboard, KBD_ACTIVATE );
 }
-
+ 
 uint32_t keyboard_handle_interrupt( interrupt_handler_t *handler, uint32_t esp )
 {
 	keyboard_t *keyboard = (keyboard_t *)handler->driver;
 	
-	uint8_t key = port8_read( &keyboard->data_port );
-	printf( "KBD 0x%X ", key );
-
+	if( has_data( keyboard ) ) {
+		uint8_t scancode = read_data( keyboard );
+		printf( "KBD 0x%X ", scancode );
+	} else {
+		printf( "SPURIOUS KBD INTERRUPT " );
+	}
+	
 	return esp;
 }
diff --git a/src/stage1_functions.asm b/src/stage1_functions.asm
index 8953b9c..46fbc74 100644
--- a/src/stage1_functions.asm
+++ b/src/stage1_functions.asm
@@ -2,7 +2,7 @@
 ; 3 * 512 for bootloader stage2 and the kernel code 
 ; (note: the first sector gets loaded by the BIOS, so
 ; subtract 1 here!)
-NOF_LOAD_SECTORS equ 20
+NOF_LOAD_SECTORS equ 21
 
 ; IN bx: begin of memory area to dump
 ; IN ax: number of words to dump