1 files changed, 41 insertions, 0 deletions
diff --git a/src/kernel/arch/i386/interrupts/irq.c b/src/kernel/arch/i386/interrupts/irq.c
new file mode 100644
index 0000000..cb33bc8
--- /dev/null
+++ b/src/kernel/arch/i386/interrupts/irq.c
@@ -0,0 +1,41 @@
+#include <kernel/arch/i386/interrupts/irq.h>
+#include <kernel/arch/i386/port_io.h>
+#include <stdint.h>
+
+static const int PIC1 = 0x20;
+static const int PIC2 = 0xA0;
+
+static void irq_unmask(uint8_t line) {
+	uint16_t pic = line < 8 ? PIC1 : PIC2;
+	line &= 7;
+
+	port_out8(pic+1, port_in8(pic+1) & ~(1 << line));
+}
+
+void irq_init(void) {
+	port_out8(PIC1, 0x11);  /* start init sequence */
+	port_out8(PIC2, 0x11);
+
+	port_out8(PIC1+1, 0x20);   /* interrupt offsets */
+	port_out8(PIC2+1, 0x30);
+
+	port_out8(PIC1+1, 0x4);   /* just look at the osdev wiki lol */
+	port_out8(PIC2+1, 0x2);
+
+	port_out8(PIC1+1, 0x1);   /* 8086 mode */
+	port_out8(PIC2+1, 0x1);
+
+	port_out8(PIC1+1, 0xfd); /* mask */
+	port_out8(PIC2+1, 0xff);
+}
+
+void irq_eoi(uint8_t line) {
+	port_out8(PIC1, 0x20);
+	if (line >= 8)
+		port_out8(PIC2, 0x20);
+}
+
+void irq_interrupt_flag(bool flag) {
+	if (flag)	asm("sti" : : : "memory");
+	else		asm("cli" : : : "memory");
+}