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-rw-r--r--arch/mips/include/asm/pgtable-bits.h283
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diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
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+++ b/arch/mips/include/asm/pgtable-bits.h
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+/*
+ * 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 */