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-rw-r--r--include/asm-cris/mmu.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/include/asm-cris/mmu.h b/include/asm-cris/mmu.h
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+++ b/include/asm-cris/mmu.h
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+/*
+ * CRIS MMU constants and PTE layout
+ */
+
+#ifndef _CRIS_MMU_H
+#define _CRIS_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_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 */
+
+#endif