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authorRoman Yeryomin <roman@advem.lv>2012-09-13 00:40:35 +0300
committerRoman Yeryomin <roman@advem.lv>2012-12-03 00:13:21 +0200
commit5deb3317cb51ac52de922bb55f8492624018906d (patch)
treec2fbe6346699d9bb0f2100490c3029519bb8fde8 /target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h
parent0239d37124f9184b478a42de8a7fa1bc85a6a6fe (diff)
Add realtek target files
Signed-off-by: Roman Yeryomin <roman@advem.lv>
Diffstat (limited to 'target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h')
-rw-r--r--target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h b/target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h
new file mode 100644
index 000000000..511421f29
--- /dev/null
+++ b/target/linux/realtek/files/arch/rlx/include/asm/pgtable-bits.h
@@ -0,0 +1,61 @@
+/*
+ * 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.
+ */
+#define _PAGE_PRESENT (1<<0) /* implemented in software */
+#define _PAGE_READ (1<<1) /* implemented in software */
+#define _PAGE_WRITE (1<<2) /* implemented in software */
+#define _PAGE_ACCESSED (1<<3) /* implemented in software */
+#define _PAGE_MODIFIED (1<<4) /* implemented in software */
+#define _PAGE_FILE (1<<4) /* set:pagecache unset:swap */
+
+#define _PAGE_GLOBAL (1<<8)
+#define _PAGE_VALID (1<<9)
+#define _PAGE_SILENT_READ (1<<9) /* synonym */
+#define _PAGE_DIRTY (1<<10) /* The MIPS dirty bit */
+#define _PAGE_SILENT_WRITE (1<<10)
+#define _CACHE_UNCACHED (1<<11)
+#define _CACHE_MASK (1<<11)
+
+
+/*
+ * Cache attributes
+ */
+#define _CACHE_CACHABLE_NONCOHERENT 0
+
+#define __READABLE (_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED)
+#define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)
+
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK)
+
+#endif /* _ASM_PGTABLE_BITS_H */