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Diffstat (limited to 'arch/nios2/include/asm/pgtable-bits.h')
-rw-r--r--arch/nios2/include/asm/pgtable-bits.h34
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/nios2/include/asm/pgtable-bits.h b/arch/nios2/include/asm/pgtable-bits.h
new file mode 100644
index 000000000..bfddff383
--- /dev/null
+++ b/arch/nios2/include/asm/pgtable-bits.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *
+ * 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.
+ */
+
+#ifndef _ASM_NIOS2_PGTABLE_BITS_H
+#define _ASM_NIOS2_PGTABLE_BITS_H
+
+/*
+ * These are actual hardware defined protection bits in the tlbacc register
+ * which looks like this:
+ *
+ * 31 30 ... 26 25 24 23 22 21 20 19 18 ... 1 0
+ * ignored........ C R W X G PFN............
+ */
+#define _PAGE_GLOBAL (1<<20)
+#define _PAGE_EXEC (1<<21)
+#define _PAGE_WRITE (1<<22)
+#define _PAGE_READ (1<<23)
+#define _PAGE_CACHED (1<<24) /* C: data access cacheable */
+
+/*
+ * Software defined bits. They are ignored by the hardware and always read back
+ * as zero, but can be written as non-zero.
+ */
+#define _PAGE_PRESENT (1<<25) /* PTE contains a translation */
+#define _PAGE_ACCESSED (1<<26) /* page referenced */
+#define _PAGE_DIRTY (1<<27) /* dirty page */
+
+#endif /* _ASM_NIOS2_PGTABLE_BITS_H */