MAS3_U0
#define PTE_MAS3_MASK (MAS3_RPN|MAS3_U2|MAS3_U0)
#define PTE_WIRED (MAS3_U0 << 2) /* page is wired (PTE only) */
#define PTE_xX (MAS3_U0 << 1) /* MAS2[UX] | MAS2[SX] */
#define PTE_UNSYNCED MAS3_U0 /* page needs isync */