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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_XPA)
/*
* Page table bit offsets used for 64 bit physical addressing on
* MIPS32r5 with XPA.
*/
enum pgtable_bits {
/* Used by TLB hardware (placed in EntryLo*) */
_PAGE_NO_EXEC_SHIFT,
_PAGE_NO_READ_SHIFT,
_PAGE_GLOBAL_SHIFT,
_PAGE_VALID_SHIFT,
_PAGE_DIRTY_SHIFT,
_CACHE_SHIFT,
/* Used only by software (masked out before writing EntryLo*) */
_PAGE_PRESENT_SHIFT = 24,
_PAGE_WRITE_SHIFT,
_PAGE_ACCESSED_SHIFT,
_PAGE_MODIFIED_SHIFT,
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
#if defined(CONFIG_HAVE_ARCH_SOFT_DIRTY)
_PAGE_SOFT_DIRTY_SHIFT,
#endif
};
/*
* Bits for extended EntryLo0/EntryLo1 registers
*/
#define _PFNX_MASK 0xffffff
#elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
/*
* Page table bit offsets used for 36 bit physical addressing on MIPS32,
* for example with Alchemy or Netlogic XLP/XLR.
*/
enum pgtable_bits {
/* Used by TLB hardware (placed in EntryLo*) */
_PAGE_GLOBAL_SHIFT,
_PAGE_VALID_SHIFT,
_PAGE_DIRTY_SHIFT,
_CACHE_SHIFT,
/* Used only by software (masked out before writing EntryLo*) */
_PAGE_PRESENT_SHIFT = _CACHE_SHIFT + 3,
_PAGE_NO_READ_SHIFT,
_PAGE_WRITE_SHIFT,
_PAGE_ACCESSED_SHIFT,
_PAGE_MODIFIED_SHIFT,
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
#if defined(CONFIG_HAVE_ARCH_SOFT_DIRTY)
_PAGE_SOFT_DIRTY_SHIFT,
#endif
};
#elif defined(CONFIG_CPU_R3K_TLB)
/* Page table bits used for r3k systems */
enum pgtable_bits {
/* Used only by software (writes to EntryLo ignored) */
_PAGE_PRESENT_SHIFT,
_PAGE_NO_READ_SHIFT,
_PAGE_WRITE_SHIFT,
_PAGE_ACCESSED_SHIFT,
_PAGE_MODIFIED_SHIFT,
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
#if defined(CONFIG_HAVE_ARCH_SOFT_DIRTY)
_PAGE_SOFT_DIRTY_SHIFT,
#endif
/* Used by TLB hardware (placed in EntryLo) */
_PAGE_GLOBAL_SHIFT = 8,
_PAGE_VALID_SHIFT,
_PAGE_DIRTY_SHIFT,
_CACHE_UNCACHED_SHIFT,
};
#else
/* Page table bits used for r4k systems */
enum pgtable_bits {
/* Used only by software (masked out before writing EntryLo*) */
_PAGE_PRESENT_SHIFT,
#if !defined(CONFIG_CPU_HAS_RIXI)
_PAGE_NO_READ_SHIFT,
#endif
_PAGE_WRITE_SHIFT,
_PAGE_ACCESSED_SHIFT,
_PAGE_MODIFIED_SHIFT,
#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
_PAGE_HUGE_SHIFT,
#endif
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
#if defined(CONFIG_HAVE_ARCH_SOFT_DIRTY)
_PAGE_SOFT_DIRTY_SHIFT,
#endif
/* Used by TLB hardware (placed in EntryLo*) */
#if defined(CONFIG_CPU_HAS_RIXI)
_PAGE_NO_EXEC_SHIFT,
_PAGE_NO_READ_SHIFT,
#endif
_PAGE_GLOBAL_SHIFT,
_PAGE_VALID_SHIFT,
_PAGE_DIRTY_SHIFT,
_CACHE_SHIFT,
};
#endif /* defined(CONFIG_PHYS_ADDR_T_64BIT && defined(CONFIG_CPU_MIPS32) */
/* Used only by software */
#define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
#define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
#define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
#define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
# define _PAGE_HUGE (1 << _PAGE_HUGE_SHIFT)
#endif
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
# define _PAGE_SPECIAL (1 << _PAGE_SPECIAL_SHIFT)
#else
# define _PAGE_SPECIAL 0
#endif
#if defined(CONFIG_HAVE_ARCH_SOFT_DIRTY)
# define _PAGE_SOFT_DIRTY (1 << _PAGE_SOFT_DIRTY_SHIFT)
#else
# define _PAGE_SOFT_DIRTY 0
#endif
/* Used by TLB hardware (placed in EntryLo*) */
#if defined(CONFIG_XPA)
# define _PAGE_NO_EXEC (1 << _PAGE_NO_EXEC_SHIFT)
#elif defined(CONFIG_CPU_HAS_RIXI)
# define _PAGE_NO_EXEC (cpu_has_rixi ? (1 << _PAGE_NO_EXEC_SHIFT) : 0)
#endif
#define _PAGE_NO_READ (1 << _PAGE_NO_READ_SHIFT)
#define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
#define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
#define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
#if defined(CONFIG_CPU_R3K_TLB)
# define _CACHE_UNCACHED (1 << _CACHE_UNCACHED_SHIFT)
# define _CACHE_MASK _CACHE_UNCACHED
# define _PFN_SHIFT PAGE_SHIFT
#else
# define _CACHE_MASK (7 << _CACHE_SHIFT)
# define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3)
#endif
#ifndef _PAGE_NO_EXEC
#define _PAGE_NO_EXEC 0
#endif
#define _PAGE_SILENT_READ _PAGE_VALID
#define _PAGE_SILENT_WRITE _PAGE_DIRTY
#define _PFN_MASK (~((1 << (_PFN_SHIFT)) - 1))
/*
* The final layouts of the PTE bits are:
*
* 64-bit, R1 or earlier: CCC D V G [S H] M A W R P
* 32-bit, R1 or earler: CCC D V G M A W R P
* 64-bit, R2 or later: CCC D V G RI/R XI [S H] M A W P
* 32-bit, R2 or later: CCC D V G RI/R XI M A W P
*/
/*
* 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)
{
#ifdef CONFIG_CPU_HAS_RIXI
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);
}
#endif
return pte_val >> _PAGE_GLOBAL_SHIFT;
}
/*
* Cache attributes
*/
#if defined(CONFIG_CPU_R3K_TLB)
#define _CACHE_CACHABLE_NONCOHERENT 0
#define _CACHE_UNCACHED_ACCELERATED _CACHE_UNCACHED
#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_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_NO_WA
#define _CACHE_CACHABLE_NO_WA (0<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_WA
#define _CACHE_CACHABLE_WA (1<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_UNCACHED
#define _CACHE_UNCACHED (2<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_NONCOHERENT
#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_CE
#define _CACHE_CACHABLE_CE (4<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_COW
#define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_CACHABLE_CUW
#define _CACHE_CACHABLE_CUW (6<<_CACHE_SHIFT)
#endif
#ifndef _CACHE_UNCACHED_ACCELERATED
#define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT)
#endif
#define __READABLE (_PAGE_SILENT_READ | _PAGE_ACCESSED)
#define __WRITEABLE (_PAGE_SILENT_WRITE | _PAGE_WRITE | _PAGE_MODIFIED)
#define _PAGE_CHG_MASK (_PAGE_ACCESSED | _PAGE_MODIFIED | \
_PAGE_SOFT_DIRTY | _PFN_MASK | \
_CACHE_MASK | _PAGE_SPECIAL)
#endif /* _ASM_PGTABLE_BITS_H */
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