diff options
Diffstat (limited to 'arch/cris/include/arch-v10/arch/mmu.h')
| -rw-r--r-- | arch/cris/include/arch-v10/arch/mmu.h | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/arch/cris/include/arch-v10/arch/mmu.h b/arch/cris/include/arch-v10/arch/mmu.h new file mode 100644 index 000000000000..df84f1716e6b --- /dev/null +++ b/arch/cris/include/arch-v10/arch/mmu.h @@ -0,0 +1,109 @@ +/* + * 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 struct +{ + unsigned int page_id; +} 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 |