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-rw-r--r--include/asm-cris/arch-v10/mmu.h106
1 files changed, 106 insertions, 0 deletions
diff --git a/include/asm-cris/arch-v10/mmu.h b/include/asm-cris/arch-v10/mmu.h
new file mode 100644
index 00000000000..d18aa00e50b
--- /dev/null
+++ b/include/asm-cris/arch-v10/mmu.h
@@ -0,0 +1,106 @@
+/*
+ * CRIS MMU constants and PTE layout
+ */
+
+#ifndef _CRIS_ARCH_MMU_H
+#define _CRIS_ARCH_MMU_H
+
+/* type used in struct mm to couple an MMU context to an active mm */
+
+typedef unsigned int mm_context_t;
+
+/* kernel memory segments */
+
+#define KSEG_F 0xf0000000UL
+#define KSEG_E 0xe0000000UL
+#define KSEG_D 0xd0000000UL
+#define KSEG_C 0xc0000000UL
+#define KSEG_B 0xb0000000UL
+#define KSEG_A 0xa0000000UL
+#define KSEG_9 0x90000000UL
+#define KSEG_8 0x80000000UL
+#define KSEG_7 0x70000000UL
+#define KSEG_6 0x60000000UL
+#define KSEG_5 0x50000000UL
+#define KSEG_4 0x40000000UL
+#define KSEG_3 0x30000000UL
+#define KSEG_2 0x20000000UL
+#define KSEG_1 0x10000000UL
+#define KSEG_0 0x00000000UL
+
+/* CRIS PTE bits (see R_TLB_LO in the register description)
+ *
+ * Bit: 31-13 12-------4 3 2 1 0
+ * ________________________________________________
+ * | pfn | reserved | global | valid | kernel | we |
+ * |_____|__________|________|_______|________|_____|
+ *
+ * (pfn = physical frame number)
+ */
+
+/* Real HW-based PTE bits. We use some synonym names so that
+ * things become less confusing in combination with the SW-based
+ * bits further below.
+ *
+ */
+
+#define _PAGE_WE (1<<0) /* page is write-enabled */
+#define _PAGE_SILENT_WRITE (1<<0) /* synonym */
+#define _PAGE_KERNEL (1<<1) /* page is kernel only */
+#define _PAGE_VALID (1<<2) /* page is valid */
+#define _PAGE_SILENT_READ (1<<2) /* synonym */
+#define _PAGE_GLOBAL (1<<3) /* global page - context is ignored */
+
+/* Bits the HW doesn't care about but the kernel uses them in SW */
+
+#define _PAGE_PRESENT (1<<4) /* page present in memory */
+#define _PAGE_FILE (1<<5) /* set: pagecache, unset: swap (when !PRESENT) */
+#define _PAGE_ACCESSED (1<<5) /* simulated in software using valid bit */
+#define _PAGE_MODIFIED (1<<6) /* simulated in software using we bit */
+#define _PAGE_READ (1<<7) /* read-enabled */
+#define _PAGE_WRITE (1<<8) /* write-enabled */
+
+/* Define some higher level generic page attributes. */
+
+#define __READABLE (_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED)
+#define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)
+
+#define _PAGE_TABLE (_PAGE_PRESENT | __READABLE | __WRITEABLE)
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED)
+
+#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
+#define PAGE_SHARED __pgprot(_PAGE_PRESENT | __READABLE | _PAGE_WRITE | \
+ _PAGE_ACCESSED)
+#define PAGE_COPY __pgprot(_PAGE_PRESENT | __READABLE) // | _PAGE_COW
+#define PAGE_READONLY __pgprot(_PAGE_PRESENT | __READABLE)
+#define PAGE_KERNEL __pgprot(_PAGE_GLOBAL | _PAGE_KERNEL | \
+ _PAGE_PRESENT | __READABLE | __WRITEABLE)
+#define _KERNPG_TABLE (_PAGE_TABLE | _PAGE_KERNEL)
+
+/*
+ * CRIS can't do page protection for execute, and considers read the same.
+ * Also, write permissions imply read permissions. This is the closest we can
+ * get..
+ */
+
+#define __P000 PAGE_NONE
+#define __P001 PAGE_READONLY
+#define __P010 PAGE_COPY
+#define __P011 PAGE_COPY
+#define __P100 PAGE_READONLY
+#define __P101 PAGE_READONLY
+#define __P110 PAGE_COPY
+#define __P111 PAGE_COPY
+
+#define __S000 PAGE_NONE
+#define __S001 PAGE_READONLY
+#define __S010 PAGE_SHARED
+#define __S011 PAGE_SHARED
+#define __S100 PAGE_READONLY
+#define __S101 PAGE_READONLY
+#define __S110 PAGE_SHARED
+#define __S111 PAGE_SHARED
+
+#define PTE_FILE_MAX_BITS 26
+
+#endif