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Diffstat (limited to 'arch/mips/include/asm/pgtable-bits.h')
| -rw-r--r-- | arch/mips/include/asm/pgtable-bits.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h new file mode 100644 index 00000000000..51b34a48c84 --- /dev/null +++ b/arch/mips/include/asm/pgtable-bits.h @@ -0,0 +1,137 @@ +/* + * 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_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 */ |