/* [<][>][^][v][top][bottom][index][help] */
/*
* 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