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Diffstat (limited to 'arch/mips/include/asm/pgtable-bits.h')
-rw-r--r-- | arch/mips/include/asm/pgtable-bits.h | 283 |
1 files changed, 283 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 0000000000..9e5fa98d1c --- /dev/null +++ b/arch/mips/include/asm/pgtable-bits.h @@ -0,0 +1,283 @@ +/* + * Copyright (C) 1994 - 2002 by Ralf Baechle + * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc. + * Copyright (C) 2002 Maciej W. Rozycki + * + * SPDX-License-Identifier: GPL-2.0 + */ +#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 */ |