sun3mmu.h

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

/*
 * Definitions for Sun3 custom MMU.
 */
#include <asm/movs.h>

#ifndef __SUN3_MMU_H__
#define __SUN3_MMU_H__

#define FC_CONTROL 3

/* MMU characteristics. */
#define SUN3_SEGMAPS_PER_CONTEXT	2048
#define SUN3_PMEGS_NUM			256
#define SUN3_CONTEXTS_NUM               8

#define SUN3_PMEG_SIZE_BITS	 17
#define SUN3_PMEG_SIZE		 (1 << SUN3_PMEG_SIZE_BITS)
#define SUN3_PMEG_MASK		 (SUN3_PMEG_SIZE - 1)

#define SUN3_PTE_SIZE_BITS       13
#define SUN3_PTE_SIZE		 (1 << SUN3_PTE_SIZE_BITS)
#define SUN3_PTE_MASK		 (SUN3_PTE_SIZE - 1)

#define SUN3_CONTROL_MASK       (0x0FFFFFFC)
#define SUN3_INVALID_PMEG	255
#define SUN3_INVALID_CONTEXT 255

#define AC_IDPROM     0x00000000    /* 34  ID PROM, R/O, byte, 32 bytes      */
#define AC_PAGEMAP    0x10000000    /* 3   Pagemap R/W, long                 */
#define AC_SEGMAP     0x20000000    /* 3   Segment map, byte                 */
#define AC_CONTEXT    0x30000000    /* 34c current mmu-context               */
#define AC_SENABLE    0x40000000    /* 34c system dvma/cache/reset enable reg*/
#define AC_UDVMA_ENB  0x50000000    /* 34  Not used on Sun boards, byte      */
#define AC_BUS_ERROR  0x60000000    /* 34  Cleared on read, byte.            */
#define AC_SYNC_ERR   0x60000000    /*   c fault type                        */
#define AC_SYNC_VA    0x60000004    /*   c fault virtual address             */
#define AC_ASYNC_ERR  0x60000008    /*   c asynchronous fault type           */
#define AC_ASYNC_VA   0x6000000c    /*   c async fault virtual address       */
#define AC_LEDS       0x70000000    /* 34  Zero turns on LEDs, byte          */
#define AC_CACHETAGS  0x80000000    /* 34c direct access to the VAC tags     */
#define AC_CACHEDDATA 0x90000000    /* 3 c direct access to the VAC data     */
#define AC_UDVMA_MAP  0xD0000000    /* 4   Not used on Sun boards, byte      */
#define AC_VME_VECTOR 0xE0000000    /* 4   For non-Autovector VME, byte      */
#define AC_BOOT_SCC   0xF0000000    /* 34  bypass to access Zilog 8530. byte.*/

#define SUN3_PAGE_CHG_MASK (SUN3_PAGE_PGNUM_MASK \
			    | SUN3_PAGE_ACCESSED | SUN3_PAGE_MODIFIED)

/* Bus access type within PTE. */
#define SUN3_PAGE_TYPE_MASK   (0x0c000000)
#define SUN3_PAGE_TYPE_MEMORY (0x00000000)
#define SUN3_PAGE_TYPE_IO     (0x04000000)
#define SUN3_PAGE_TYPE_VME16  (0x08000000)
#define SUN3_PAGE_TYPE_VME32  (0x0c000000)

/* Mask for page number within PTE. */
#define SUN3_PAGE_PGNUM_MASK (0x0007FFFF)

/* Bits within bus-error register. */
#define SUN3_BUSERR_WATCHDOG	(0x01)
#define SUN3_BUSERR_unused	(0x02)
#define SUN3_BUSERR_FPAENERR	(0x04)
#define SUN3_BUSERR_FPABERR	(0x08)
#define SUN3_BUSERR_VMEBERR	(0x10)
#define SUN3_BUSERR_TIMEOUT	(0x20)
#define SUN3_BUSERR_PROTERR	(0x40)
#define SUN3_BUSERR_INVALID	(0x80)

#ifndef __ASSEMBLY__

/* Read bus error status register (implicitly clearing it). */
extern __inline__ unsigned char sun3_get_buserr (void)
{
	unsigned char sfc, c;

	GET_SFC (sfc);
	SET_SFC (FC_CONTROL);
	GET_CONTROL_BYTE (AC_BUS_ERROR, c);
	SET_SFC (sfc);

	return c;
}

/* Read segmap from hardware MMU. */
extern __inline__ unsigned long sun3_get_segmap (unsigned long addr)
{
        register unsigned long entry;
        unsigned char c, sfc;

        GET_SFC (sfc);
        SET_SFC (FC_CONTROL);
        GET_CONTROL_BYTE (AC_SEGMAP | (addr & SUN3_CONTROL_MASK), c);
        SET_SFC (sfc);
        entry = c;

        return entry;
}

/* Write segmap to hardware MMU. */
extern __inline__ void sun3_put_segmap (unsigned long addr, unsigned long entry)
{
        unsigned char sfc;

        GET_DFC (sfc);
        SET_DFC (FC_CONTROL);
        SET_CONTROL_BYTE (AC_SEGMAP | (addr & SUN3_CONTROL_MASK), entry);
	SET_DFC (sfc);

        return;
}

/* Read PTE from hardware MMU. */
extern __inline__ unsigned long sun3_get_pte (unsigned long addr)
{
        register unsigned long entry;
        unsigned char sfc;

        GET_SFC (sfc);
        SET_SFC (FC_CONTROL);
        GET_CONTROL_WORD (AC_PAGEMAP | (addr & SUN3_CONTROL_MASK), entry);
        SET_SFC (sfc);

        return entry;
}

/* Write PTE to hardware MMU. */
extern __inline__ void sun3_put_pte (unsigned long addr, unsigned long entry)
{
        unsigned char sfc;

        GET_DFC (sfc);
        SET_DFC (FC_CONTROL);
        SET_CONTROL_WORD (AC_PAGEMAP | (addr & SUN3_CONTROL_MASK), entry);
	SET_DFC (sfc);

        return;
}

/* get current context */
extern __inline__ unsigned char sun3_get_context(void)
{
	unsigned char sfc, c;

	GET_SFC(sfc);
	SET_SFC(FC_CONTROL);
	GET_CONTROL_BYTE(AC_CONTEXT, c);
	SET_SFC(sfc);
	
	return c;
}

/* set alternate context */
extern __inline__ void sun3_put_context(unsigned char c)
{
	unsigned char dfc;
	GET_DFC(dfc);
	SET_DFC(FC_CONTROL);
	SET_CONTROL_BYTE(AC_CONTEXT, c);
	SET_DFC(dfc);
	
	return;
}


#endif	/* !__ASSEMBLY__ */

#endif	/* !__SUN3_MMU_H__ */