1 files changed, 264 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 000000000..f88a48cd6
--- /dev/null
+++ b/arch/mips/include/asm/pgtable-bits.h
@@ -0,0 +1,264 @@
+/*
+ * 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,
+};
+
+/*
+ * 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,
+};
+
+#elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+
+/* 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,
+
+	/* 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_64BIT) && defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
+	_PAGE_HUGE_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_64BIT) && defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
+# define _PAGE_HUGE		(1 << _PAGE_HUGE_SHIFT)
+#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_R3000) || defined(CONFIG_CPU_TX39XX)
+# 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_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_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 */