Big code refactor, get rid of HAL entirely

kernel/intr/pic.c

@@ -0,0 +1,46 @@
+#include <stddef.h>
+#include <stdint.h>
+#include "io/io.h"
+#include "intr/pic.h"
+#include "intr/intr.h"
+
+#define PIC1_CMD  0x0020
+#define PIC1_DATA 0x0021
+#define PIC2_CMD  0x00A0
+#define PIC2_DATA 0x00A1
+
+#define PIC_EOI 0x20
+
+#define ICW1_ICW4   0x01
+#define ICW1_SINGLE 0x02
+#define ICW1_ADI    0x04
+#define ICW1_LTIM   0x08
+#define ICW1_INIT   0x10
+
+#define ICW4_8086       0x01
+#define ICW4_AUTO       0x02
+#define ICW4_BUFSLAVE   0x04
+#define ICW4_BUFMASTER  0x0C
+#define ICW4_SFNM       0x10
+
+void intr_pic_init(void) {
+  io_out8(PIC1_CMD, ICW1_INIT | ICW1_ICW4);
+  io_out8(PIC2_CMD, ICW1_INIT | ICW1_ICW4);
+
+  io_out8(PIC1_DATA, INTR_IRQBASE);
+  io_out8(PIC2_DATA, INTR_IRQBASE+8);
+
+  io_out8(PIC1_DATA, 2);
+  io_out8(PIC2_DATA, 2);
+
+  io_out8(PIC1_DATA, ICW4_8086);
+  io_out8(PIC2_DATA, ICW4_8086);
+
+  io_out8(PIC1_DATA, 0);
+  io_out8(PIC2_DATA, 0);
+}
+
+void intr_pic_eoi(void) {
+  io_out8(PIC2_CMD, PIC_EOI);
+  io_out8(PIC1_CMD, PIC_EOI);
+}