+#define HT_MSI_FLAGS 0x02 /* Offset to flags */
+#define HT_MSI_FLAGS_ENABLE 0x1 /* Mapping enable */
+#define HT_MSI_FLAGS_FIXED 0x2 /* Fixed mapping only */
+#define HT_MSI_FIXED_ADDR 0x00000000FEE00000ULL /* Fixed addr */
+#define HT_MSI_ADDR_LO 0x04 /* Offset to low addr bits */
+#define HT_MSI_ADDR_LO_MASK 0xFFF00000 /* Low address bit mask */
+#define HT_MSI_ADDR_HI 0x08 /* Offset to high addr bits */