/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1994 - 2002 by Ralf Baechle * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc. * Copyright (C) 2002 Maciej W. Rozycki */ #ifndef _ASM_PGTABLE_BITS_H #define _ASM_PGTABLE_BITS_H /* * Note that we shift the lower 32bits of each EntryLo[01] entry * 6 bits to the left. That way we can convert the PFN into the * physical address by a single 'and' operation and gain 6 additional * bits for storing information which isn't present in a normal * MIPS page table. * * Similar to the Alpha port, we need to keep track of the ref * and mod bits in software. We have a software "yeah you can read * from this page" bit, and a hardware one which actually lets the * process read from the page. On the same token we have a software * writable bit and the real hardware one which actually lets the * process write to the page, this keeps a mod bit via the hardware * dirty bit. * * Certain revisions of the R4000 and R5000 have a bug where if a * certain sequence occurs in the last 3 instructions of an executable * page, and the following page is not mapped, the cpu can do * unpredictable things. The code (when it is written) to deal with * this problem will be in the update_mmu_cache() code for the r4k. */ #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) #define _PAGE_PRESENT (1<<6) /* implemented in software */ #define _PAGE_READ (1<<7) /* implemented in software */ #define _PAGE_WRITE (1<<8) /* implemented in software */ #define _PAGE_ACCESSED (1<<9) /* implemented in software */ #define _PAGE_MODIFIED (1<<10) /* implemented in software */ #define _PAGE_FILE (1<<10) /* set:pagecache unset:swap */ #define _PAGE_R4KBUG (1<<0) /* workaround for r4k bug */ #define _PAGE_GLOBAL (1<<0) #define _PAGE_VALID (1<<1) #define _PAGE_SILENT_READ (1<<1) /* synonym */ #define _PAGE_DIRTY (1<<2) /* The MIPS dirty bit */ #define _PAGE_SILENT_WRITE (1<<2) #define _CACHE_SHIFT 3 #define _CACHE_MASK (7<<3) #else #define _PAGE_PRESENT (1<<0) /* implemented in software */ #define _PAGE_READ (1<<1) /* implemented in software */ #define _PAGE_WRITE (1<<2) /* implemented in software */ #define _PAGE_ACCESSED (1<<3) /* implemented in software */ #define _PAGE_MODIFIED (1<<4) /* implemented in software */ #define _PAGE_FILE (1<<4) /* set:pagecache unset:swap */ #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) #define _PAGE_GLOBAL (1<<8) #define _PAGE_VALID (1<<9) #define _PAGE_SILENT_READ (1<<9) /* synonym */ #define _PAGE_DIRTY (1<<10) /* The MIPS dirty bit */ #define _PAGE_SILENT_WRITE (1<<10) #define _CACHE_UNCACHED (1<<11) #define _CACHE_MASK (1<<11) #else #define _PAGE_R4KBUG (1<<5) /* workaround for r4k bug */ #define _PAGE_HUGE (1<<5) /* huge tlb page */ #define _PAGE_GLOBAL (1<<6) #define _PAGE_VALID (1<<7) #define _PAGE_SILENT_READ (1<<7) /* synonym */ #define _PAGE_DIRTY (1<<8) /* The MIPS dirty bit */ #define _PAGE_SILENT_WRITE (1<<8) #define _CACHE_SHIFT 9 #define _CACHE_MASK (7<<9) #endif #endif /* defined(CONFIG_64BIT_PHYS_ADDR && defined(CONFIG_CPU_MIPS32) */ /* * Cache attributes */ #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) #define _CACHE_CACHABLE_NONCOHERENT 0 #elif defined(CONFIG_CPU_SB1) /* No penalty for being coherent on the SB1, so just use it for "noncoherent" spaces, too. Shouldn't hurt. */ #define _CACHE_UNCACHED (2<<_CACHE_SHIFT) #define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT) #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT) #define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT) #elif defined(CONFIG_CPU_RM9000) #define _CACHE_WT (0<<_CACHE_SHIFT) #define _CACHE_WTWA (1<<_CACHE_SHIFT) #define _CACHE_UC_B (2<<_CACHE_SHIFT) #define _CACHE_WB (3<<_CACHE_SHIFT) #define _CACHE_CWBEA (4<<_CACHE_SHIFT) #define _CACHE_CWB (5<<_CACHE_SHIFT) #define _CACHE_UCNB (6<<_CACHE_SHIFT) #define _CACHE_FPC (7<<_CACHE_SHIFT) #define _CACHE_UNCACHED _CACHE_UC_B #define _CACHE_CACHABLE_NONCOHERENT _CACHE_WB #else #define _CACHE_CACHABLE_NO_WA (0<<_CACHE_SHIFT) /* R4600 only */ #define _CACHE_CACHABLE_WA (1<<_CACHE_SHIFT) /* R4600 only */ #define _CACHE_UNCACHED (2<<_CACHE_SHIFT) /* R4[0246]00 */ #define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* R4[0246]00 */ #define _CACHE_CACHABLE_CE (4<<_CACHE_SHIFT) /* R4[04]00MC only */ #define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT) /* R4[04]00MC only */ #define _CACHE_CACHABLE_COHERENT (5<<_CACHE_SHIFT) /* MIPS32R2 CMP */ #define _CACHE_CACHABLE_CUW (6<<_CACHE_SHIFT) /* R4[04]00MC only */ #define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT) /* R10000 only */ #endif #define __READABLE (_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED) #define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED) #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK) #endif /* _ASM_PGTABLE_BITS_H */