#define HPET_ID_LEGSUP 0x00008000
#define HPET_ID_NUMBER 0x00001f00
#define HPET_ID_REV 0x000000ff
+#define HPET_ID_NUMBER_SHIFT 8
#define HPET_CFG_ENABLE 0x001
#define HPET_CFG_LEGACY 0x002
+#define HPET_LEGACY_8254 2
+#define HPET_LEGACY_RTC 8
#define HPET_TN_ENABLE 0x004
#define HPET_TN_PERIODIC 0x008