feat(pit): add pit isr, empty handler and unmasked pit irq

Signed-off-by: Julien CLEMENT <julien.clement@epita.fr>

k/Makefile

@@ -36,6 +36,7 @@ OBJS	= \
 	  events/isr.o \
 	  events/pic/pic.o \
 	  events/pic/keyboard.o \
+	  events/pic/pit.o \
 	  utils/ring_buffer.o
 
 

k/events/idt.c

@@ -2,6 +2,7 @@
 #include "stdio.h"
 #include "pic/pic.h"
 #include "pic/keyboard.h"
+#include "pic/pit.h"
 #include "io.h"
 
 static struct idt idt = { 0 };
@@ -39,8 +40,8 @@ static struct idt_entry_descriptor idt_entries_descriptors[IDT_NB_ENTRIES] = {
     {0, {0, 0, 0}, 0}, // 29
     {0, {0, 0, 0}, 0}, // 30
     {0, {0, 0, 0}, 0}, // 31
-    {0, {0, 0, 0}, 0}, // 32
-    {(uint32_t)&isr_keyboard, KERNEL_CS_SEGMENT_SELECTOR, INTERRUPT_TYPE}, // 33
+    {(uint32_t)&isr_pit, KERNEL_CS_SEGMENT_SELECTOR, INTERRUPT_TYPE}, // 32
+    {(uint32_t)&isr_keyboard, KERNEL_CS_SEGMENT_SELECTOR, INTERRUPT_TYPE} // 33
 };
 
 void interrupt_handler(struct isr_param *isr_param)
@@ -49,6 +50,9 @@ void interrupt_handler(struct isr_param *isr_param)
 
     switch (isr_param->int_vector)
     {
+        case PIT_INT_VECTOR:
+            pit_handler();
+            break;
         case KEYBOARD_INT_VECTOR:
             keyboard_handler();
             break;

k/events/idt.h

@@ -12,6 +12,7 @@
 #define INTERRUPT_TYPE 0x6
 #define TRAP_TYPE      0x7
 
+#define PIT_INT_VECTOR 32
 #define KEYBOARD_INT_VECTOR 33
 
 struct idt_entry

k/events/isr.S

@@ -44,4 +44,5 @@ isr_callback_no_error(isr_machine_check, 18)
 isr_callback_no_error(isr_simd_floating_point_exception, 19)
 isr_callback_no_error(isr_virtualization_exception, 20)
 isr_callback_error(isr_control_protection_exception, 21)
+isr_callback_no_error(isr_pit, 32)
 isr_callback_no_error(isr_keyboard, 33)

k/events/isr.h

@@ -28,6 +28,7 @@ void isr_machine_check(void);
 void isr_simd_floating_point_exception(void);
 void isr_virtualization_exception(void);
 void isr_control_protection_exception(void);
+void isr_pit(void);
 void isr_keyboard(void);
 
 #endif  /* !ISR_H */

k/events/pic/pic.c

@@ -31,7 +31,8 @@ static void send_icw4(void)
 
 static void mask_irqs(void)
 {
-    outb(MASTER_PIC_B, 0xff ^ 0x2);
+    outb(MASTER_PIC_B, IRQ2_PIN | IRQ3_PIN | IRQ4_PIN | IRQ5_PIN | IRQ6_PIN
+            | IRQ7_PIN);
     outb(SLAVE_PIC_B, 0xff);
 }
 

k/events/pic/pic.h

@@ -8,6 +8,15 @@
 
 #define ICW1 0x11
 
+#define IRQ0_PIN 0x1
+#define IRQ1_PIN 0x2
+#define IRQ2_PIN 0x4
+#define IRQ3_PIN 0x8
+#define IRQ4_PIN 0x10
+#define IRQ5_PIN 0x20
+#define IRQ6_PIN 0x40
+#define IRQ7_PIN 0x80
+
 void init_pic(void);
 void acknowledge(uint32_t int_vector);
 

k/events/pic/pit.c

@@ -0,0 +1,9 @@
+#include "pit.h"
+
+void pit_handler(void)
+{
+}
+
+unsigned long gettick(void)
+{
+}

k/events/pic/pit.h

@@ -0,0 +1,12 @@
+#ifndef PIT_H
+#define PIT_H
+
+#define PIT_COUNTER_0 0x40
+#define PIT_COUNTER_1 0x41
+#define PIT_COUNTER_2 0x42
+#define PIT_CONTROL_REGISTER 0x43
+
+void pit_handler(void);
+unsigned long gettick(void);
+
+#endif /* !PIT_H */

k/k.c

@@ -53,8 +53,6 @@ void k_main(unsigned long magic, multiboot_info_t *info)
             :);
     printf("bonjour\r\n");
 
-
-
     for (unsigned i = 0; ; ) {
         *fb = star[i++ % 4];
     }