/* * 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) #elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) #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 */ #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 /* 'Normal' r4K case */ /* * When using the RI/XI bit support, we have 13 bits of flags below * the physical address. The RI/XI bits are placed such that a SRL 5 * can strip off the software bits, then a ROTR 2 can move the RI/XI * into bits [63:62]. This also limits physical address to 56 bits, * which is more than we need right now. */ /* implemented in software */ #define _PAGE_PRESENT_SHIFT (0) #define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT) /* implemented in software, should be unused if cpu_has_rixi. */ #define _PAGE_READ_SHIFT (cpu_has_rixi ? _PAGE_PRESENT_SHIFT : _PAGE_PRESENT_SHIFT + 1) #define _PAGE_READ ({BUG_ON(cpu_has_rixi); 1 << _PAGE_READ_SHIFT; }) /* implemented in software */ #define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1) #define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT) /* implemented in software */ #define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1) #define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT) /* implemented in software */ #define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1) #define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT) /* set:pagecache unset:swap */ #define _PAGE_FILE (_PAGE_MODIFIED) #ifdef CONFIG_HUGETLB_PAGE /* huge tlb page */ #define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT + 1) #define _PAGE_HUGE (1 << _PAGE_HUGE_SHIFT) #else #define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT) #define _PAGE_HUGE ({BUG(); 1; }) /* Dummy value */ #endif /* Page cannot be executed */ #define _PAGE_NO_EXEC_SHIFT (cpu_has_rixi ? _PAGE_HUGE_SHIFT + 1 : _PAGE_HUGE_SHIFT) #define _PAGE_NO_EXEC ({BUG_ON(!cpu_has_rixi); 1 << _PAGE_NO_EXEC_SHIFT; }) /* Page cannot be read */ #define _PAGE_NO_READ_SHIFT (cpu_has_rixi ? _PAGE_NO_EXEC_SHIFT + 1 : _PAGE_NO_EXEC_SHIFT) #define _PAGE_NO_READ ({BUG_ON(!cpu_has_rixi); 1 << _PAGE_NO_READ_SHIFT; }) #define _PAGE_GLOBAL_SHIFT (_PAGE_NO_READ_SHIFT + 1) #define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT) #define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1) #define _PAGE_VALID (1 << _PAGE_VALID_SHIFT) /* synonym */ #define _PAGE_SILENT_READ (_PAGE_VALID) /* The MIPS dirty bit */ #define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1) #define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT) #define _PAGE_SILENT_WRITE (_PAGE_DIRTY) #define _CACHE_SHIFT (_PAGE_DIRTY_SHIFT + 1) #define _CACHE_MASK (7 << _CACHE_SHIFT) #define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3) #endif /* defined(CONFIG_64BIT_PHYS_ADDR && defined(CONFIG_CPU_MIPS32) */ #ifndef _PFN_SHIFT #define _PFN_SHIFT PAGE_SHIFT #endif #define _PFN_MASK (~((1 << (_PFN_SHIFT)) - 1)) #ifndef _PAGE_NO_READ #define _PAGE_NO_READ ({BUG(); 0; }) #define _PAGE_NO_READ_SHIFT ({BUG(); 0; }) #endif #ifndef _PAGE_NO_EXEC #define _PAGE_NO_EXEC ({BUG(); 0; }) #endif #ifndef _PAGE_GLOBAL_SHIFT #define _PAGE_GLOBAL_SHIFT ilog2(_PAGE_GLOBAL) #endif #ifndef __ASSEMBLY__ /* * pte_to_entrylo converts a page table entry (PTE) into a Mips * entrylo0/1 value. */ static inline uint64_t pte_to_entrylo(unsigned long pte_val) { if (cpu_has_rixi) { int sa; #ifdef CONFIG_32BIT sa = 31 - _PAGE_NO_READ_SHIFT; #else sa = 63 - _PAGE_NO_READ_SHIFT; #endif /* * C has no way to express that this is a DSRL * _PAGE_NO_EXEC_SHIFT followed by a ROTR 2. Luckily * in the fast path this is done in assembly */ return (pte_val >> _PAGE_GLOBAL_SHIFT) | ((pte_val & (_PAGE_NO_EXEC | _PAGE_NO_READ)) << sa); } return pte_val >> _PAGE_GLOBAL_SHIFT; } #endif /* * 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_SILENT_READ | _PAGE_ACCESSED | (cpu_has_rixi ? 0 : _PAGE_READ)) #define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED) #define _PAGE_CHG_MASK (_PFN_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK) #endif /* _ASM_PGTABLE_BITS_H */