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- pgtable-bits.h
/*
* 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_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
/*
* The following bits are implemented by the TLB hardware
*/
#define _PAGE_NO_EXEC_SHIFT 0
#define _PAGE_NO_EXEC (1 << _PAGE_NO_EXEC_SHIFT)
#define _PAGE_NO_READ_SHIFT (_PAGE_NO_EXEC_SHIFT + 1)
#define _PAGE_NO_READ (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)
#define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1)
#define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
#define _CACHE_SHIFT (_PAGE_DIRTY_SHIFT + 1)
#define _CACHE_MASK (7 << _CACHE_SHIFT)
/*
* The following bits are implemented in software
*/
#define _PAGE_PRESENT_SHIFT (24)
#define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
#define _PAGE_READ_SHIFT (_PAGE_PRESENT_SHIFT + 1)
#define _PAGE_READ (1 << _PAGE_READ_SHIFT)
#define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1)
#define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
#define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1)
#define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
#define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1)
#define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
#define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3)
/*
* Bits for extended EntryLo0/EntryLo1 registers
*/
#define _PFNX_MASK 0xffffff
#elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
/*
* The following bits are implemented in software
*/
#define _PAGE_PRESENT_SHIFT (0)
#define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
#define _PAGE_READ_SHIFT (_PAGE_PRESENT_SHIFT + 1)
#define _PAGE_READ (1 << _PAGE_READ_SHIFT)
#define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1)
#define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
#define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1)
#define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
#define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1)
#define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
/*
* The following bits are implemented by the TLB hardware
*/
#define _PAGE_GLOBAL_SHIFT (_PAGE_MODIFIED_SHIFT + 4)
#define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
#define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1)
#define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
#define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1)
#define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
#define _CACHE_UNCACHED_SHIFT (_PAGE_DIRTY_SHIFT + 1)
#define _CACHE_UNCACHED (1 << _CACHE_UNCACHED_SHIFT)
#define _CACHE_MASK _CACHE_UNCACHED
#define _PFN_SHIFT PAGE_SHIFT
#else
/*
* Below are the "Normal" R4K cases
*/
/*
* The following bits are implemented in software
*/
#define _PAGE_PRESENT_SHIFT 0
#define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
/* R2 or later cores check for RI/XI support to determine _PAGE_READ */
#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
#define _PAGE_WRITE_SHIFT (_PAGE_PRESENT_SHIFT + 1)
#define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
#else
#define _PAGE_READ_SHIFT (_PAGE_PRESENT_SHIFT + 1)
#define _PAGE_READ (1 << _PAGE_READ_SHIFT)
#define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1)
#define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
#endif
#define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1)
#define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
#define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1)
#define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
#if defined(CONFIG_64BIT) && defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
/* Huge TLB page */
#define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT + 1)
#define _PAGE_HUGE (1 << _PAGE_HUGE_SHIFT)
#define _PAGE_SPLITTING_SHIFT (_PAGE_HUGE_SHIFT + 1)
#define _PAGE_SPLITTING (1 << _PAGE_SPLITTING_SHIFT)
#endif /* CONFIG_64BIT && CONFIG_MIPS_HUGE_TLB_SUPPORT */
#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
/* XI - page cannot be executed */
#ifdef _PAGE_SPLITTING_SHIFT
#define _PAGE_NO_EXEC_SHIFT (_PAGE_SPLITTING_SHIFT + 1)
#else
#define _PAGE_NO_EXEC_SHIFT (_PAGE_MODIFIED_SHIFT + 1)
#endif
#define _PAGE_NO_EXEC (cpu_has_rixi ? (1 << _PAGE_NO_EXEC_SHIFT) : 0)
/* RI - page cannot be read */
#define _PAGE_READ_SHIFT (_PAGE_NO_EXEC_SHIFT + 1)
#define _PAGE_READ (cpu_has_rixi ? 0 : (1 << _PAGE_READ_SHIFT))
#define _PAGE_NO_READ_SHIFT _PAGE_READ_SHIFT
#define _PAGE_NO_READ (cpu_has_rixi ? (1 << _PAGE_READ_SHIFT) : 0)
#endif /* defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) */
#if defined(_PAGE_NO_READ_SHIFT)
#define _PAGE_GLOBAL_SHIFT (_PAGE_NO_READ_SHIFT + 1)
#elif defined(_PAGE_SPLITTING_SHIFT)
#define _PAGE_GLOBAL_SHIFT (_PAGE_SPLITTING_SHIFT + 1)
#else
#define _PAGE_GLOBAL_SHIFT (_PAGE_MODIFIED_SHIFT + 1)
#endif
#define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
#define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1)
#define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
#define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1)
#define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
#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_PHYS_ADDR_T_64BIT && defined(CONFIG_CPU_MIPS32) */
#ifndef _PAGE_NO_EXEC
#define _PAGE_NO_EXEC 0
#endif
#ifndef _PAGE_NO_READ
#define _PAGE_NO_READ 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
*/
#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 defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
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;
}
#endif
/*
* Cache attributes
*/
#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
#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)
#elif defined(CONFIG_CPU_LOONGSON3)
/* Using COHERENT flag for NONCOHERENT doesn't hurt. */
#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
#define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
#elif defined(CONFIG_MACH_INGENIC)
/* Ingenic uses the WA bit to achieve write-combine memory writes */
#define _CACHE_UNCACHED_ACCELERATED (1<<_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_READ | _PAGE_ACCESSED)
#define __WRITEABLE (_PAGE_SILENT_WRITE | _PAGE_WRITE | _PAGE_MODIFIED)
#define _PAGE_CHG_MASK (_PAGE_ACCESSED | _PAGE_MODIFIED | \
_PFN_MASK | _CACHE_MASK)
#endif /* _ASM_PGTABLE_BITS_H */