+/* i8259A PIC registers */
+#define PIC_MASTER_CMD 0x20
+#define PIC_MASTER_IMR 0x21
+#define PIC_MASTER_ISR PIC_MASTER_CMD
+#define PIC_MASTER_POLL PIC_MASTER_ISR
+#define PIC_MASTER_OCW3 PIC_MASTER_ISR
+#define PIC_SLAVE_CMD 0xa0
+#define PIC_SLAVE_IMR 0xa1
+
+/* i8259A PIC related value */
+#define PIC_CASCADE_IR 2
+#define MASTER_ICW4_DEFAULT 0x01
+#define SLAVE_ICW4_DEFAULT 0x01
+#define PIC_ICW4_AEOI 2
+