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/* * 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 kernel_uses_smartmips_rixi. */#define _PAGE_READ_SHIFT	(kernel_uses_smartmips_rixi ? _PAGE_PRESENT_SHIFT : _PAGE_PRESENT_SHIFT + 1)#define _PAGE_READ ({if (kernel_uses_smartmips_rixi) BUG(); 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	(kernel_uses_smartmips_rixi ? _PAGE_HUGE_SHIFT + 1 : _PAGE_HUGE_SHIFT)#define _PAGE_NO_EXEC		({if (!kernel_uses_smartmips_rixi) BUG(); 1 << _PAGE_NO_EXEC_SHIFT; }) /* Page cannot be read */#define _PAGE_NO_READ_SHIFT	(kernel_uses_smartmips_rixi ? _PAGE_NO_EXEC_SHIFT + 1 : _PAGE_NO_EXEC_SHIFT)#define _PAGE_NO_READ		({if (!kernel_uses_smartmips_rixi) BUG(); 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 (kernel_uses_smartmips_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 | (kernel_uses_smartmips_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 */