Commit 91521c2e authored by Greg Ungerer's avatar Greg Ungerer
Browse files

m68k: page table support definitions and code for ColdFire MMU 



The ColdFire V4e MMU is nothing like any of the other m68k MMU's.
So we need to create a set of definitions and support routines
for the kernels paging functions.

This is largely taken from Freescales BSP code for this (though it
was a 2.6.25 kernel). I have cleaned it up alot from the original.

Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.org>
Acked-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: default avatarMatt Waddel <mwaddel@yahoo.com>
Acked-by: default avatarKurt Mahan <kmahan@xmission.com>
parent bbc6f1ba

arch/m68k/include/asm/mcf_pgtable.h

0 → 100644
+425 −0
Original line number Diff line number Diff line 
#ifndef _MCF_PGTABLE_H

#define _MCF_PGTABLE_H



#include <asm/mcfmmu.h>

#include <asm/page.h>



/*

 * MMUDR bits, in proper place. We write these directly into the MMUDR

 * after masking from the pte.

 */

#define CF_PAGE_LOCKED		MMUDR_LK	/* 0x00000002 */

#define CF_PAGE_EXEC		MMUDR_X		/* 0x00000004 */

#define CF_PAGE_WRITABLE	MMUDR_W		/* 0x00000008 */

#define CF_PAGE_READABLE	MMUDR_R		/* 0x00000010 */

#define CF_PAGE_SYSTEM		MMUDR_SP	/* 0x00000020 */

#define CF_PAGE_COPYBACK	MMUDR_CM_CCB	/* 0x00000040 */

#define CF_PAGE_NOCACHE		MMUDR_CM_NCP	/* 0x00000080 */



#define CF_CACHEMASK		(~MMUDR_CM_CCB)

#define CF_PAGE_MMUDR_MASK	0x000000fe



#define _PAGE_NOCACHE030	CF_PAGE_NOCACHE



/*

 * MMUTR bits, need shifting down.

 */

#define CF_PAGE_MMUTR_MASK	0x00000c00

#define CF_PAGE_MMUTR_SHIFT	10



#define CF_PAGE_VALID		(MMUTR_V << CF_PAGE_MMUTR_SHIFT)

#define CF_PAGE_SHARED		(MMUTR_SG << CF_PAGE_MMUTR_SHIFT)



/*

 * Fake bits, not implemented in CF, will get masked out before

 * hitting hardware.

 */

#define CF_PAGE_DIRTY		0x00000001

#define CF_PAGE_FILE		0x00000200

#define CF_PAGE_ACCESSED	0x00001000



#define _PAGE_CACHE040		0x020   /* 68040 cache mode, cachable, copyback */

#define _PAGE_NOCACHE_S		0x040   /* 68040 no-cache mode, serialized */

#define _PAGE_NOCACHE		0x060   /* 68040 cache mode, non-serialized */

#define _PAGE_CACHE040W		0x000   /* 68040 cache mode, cachable, write-through */

#define _DESCTYPE_MASK		0x003

#define _CACHEMASK040		(~0x060)

#define _PAGE_GLOBAL040		0x400   /* 68040 global bit, used for kva descs */



/*

 * Externally used page protection values.

 */

#define _PAGE_PRESENT	(CF_PAGE_VALID)

#define _PAGE_ACCESSED	(CF_PAGE_ACCESSED)

#define _PAGE_DIRTY	(CF_PAGE_DIRTY)

#define _PAGE_READWRITE (CF_PAGE_READABLE \

				| CF_PAGE_WRITABLE \

				| CF_PAGE_SYSTEM \

				| CF_PAGE_SHARED)



/*

 * Compound page protection values.

 */

#define PAGE_NONE	__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED)



#define PAGE_SHARED     __pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_SHARED)



#define PAGE_INIT	__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_WRITABLE \

				 | CF_PAGE_EXEC \

				 | CF_PAGE_SYSTEM)



#define PAGE_KERNEL	__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_WRITABLE \

				 | CF_PAGE_EXEC \

				 | CF_PAGE_SYSTEM)



#define PAGE_COPY	__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_DIRTY)



/*

 * Page protections for initialising protection_map. See mm/mmap.c

 * for use. In general, the bit positions are xwr, and P-items are

 * private, the S-items are shared.

 */

#define __P000		PAGE_NONE

#define __P001		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE)

#define __P010		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_WRITABLE)

#define __P011		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_WRITABLE)

#define __P100		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_EXEC)

#define __P101		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_EXEC)

#define __P110		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_WRITABLE \

				 | CF_PAGE_EXEC)

#define __P111		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_WRITABLE \

				 | CF_PAGE_EXEC)



#define __S000		PAGE_NONE

#define __S001		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE)

#define __S010		PAGE_SHARED

#define __S011		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_SHARED \

				 | CF_PAGE_READABLE)

#define __S100		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_EXEC)

#define __S101		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_EXEC)

#define __S110		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_SHARED \

				 | CF_PAGE_EXEC)

#define __S111		__pgprot(CF_PAGE_VALID \

				 | CF_PAGE_ACCESSED \

				 | CF_PAGE_SHARED \

				 | CF_PAGE_READABLE \

				 | CF_PAGE_EXEC)



#define PTE_MASK	PAGE_MASK

#define CF_PAGE_CHG_MASK (PTE_MASK | CF_PAGE_ACCESSED | CF_PAGE_DIRTY)



#ifndef __ASSEMBLY__



/*

 * Conversion functions: convert a page and protection to a page entry,

 * and a page entry and page directory to the page they refer to.

 */

#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))



static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)

{

	pte_val(pte) = (pte_val(pte) & CF_PAGE_CHG_MASK) | pgprot_val(newprot);

	return pte;

}



#define pmd_set(pmdp, ptep) do {} while (0)



static inline void pgd_set(pgd_t *pgdp, pmd_t *pmdp)

{

	pgd_val(*pgdp) = virt_to_phys(pmdp);

}



#define __pte_page(pte)	((unsigned long) (pte_val(pte) & PAGE_MASK))

#define __pmd_page(pmd)	((unsigned long) (pmd_val(pmd)))



static inline int pte_none(pte_t pte)

{

	return !pte_val(pte);

}



static inline int pte_present(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_VALID;

}



static inline void pte_clear(struct mm_struct *mm, unsigned long addr,

	pte_t *ptep)

{

	pte_val(*ptep) = 0;

}



#define pte_pagenr(pte)	((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)

#define pte_page(pte)	virt_to_page(__pte_page(pte))



static inline int pmd_none2(pmd_t *pmd) { return !pmd_val(*pmd); }

#define pmd_none(pmd) pmd_none2(&(pmd))

static inline int pmd_bad2(pmd_t *pmd) { return 0; }

#define pmd_bad(pmd) pmd_bad2(&(pmd))

#define pmd_present(pmd) (!pmd_none2(&(pmd)))

static inline void pmd_clear(pmd_t *pmdp) { pmd_val(*pmdp) = 0; }



static inline int pgd_none(pgd_t pgd) { return 0; }

static inline int pgd_bad(pgd_t pgd) { return 0; }

static inline int pgd_present(pgd_t pgd) { return 1; }

static inline void pgd_clear(pgd_t *pgdp) {}



#define pte_ERROR(e) \

	printk(KERN_ERR "%s:%d: bad pte %08lx.\n",	\

	__FILE__, __LINE__, pte_val(e))

#define pmd_ERROR(e) \

	printk(KERN_ERR "%s:%d: bad pmd %08lx.\n",	\

	__FILE__, __LINE__, pmd_val(e))

#define pgd_ERROR(e) \

	printk(KERN_ERR "%s:%d: bad pgd %08lx.\n",	\

	__FILE__, __LINE__, pgd_val(e))



/*

 * The following only work if pte_present() is true.

 * Undefined behaviour if not...

 * [we have the full set here even if they don't change from m68k]

 */

static inline int pte_read(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_READABLE;

}



static inline int pte_write(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_WRITABLE;

}



static inline int pte_exec(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_EXEC;

}



static inline int pte_dirty(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_DIRTY;

}



static inline int pte_young(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_ACCESSED;

}



static inline int pte_file(pte_t pte)

{

	return pte_val(pte) & CF_PAGE_FILE;

}



static inline int pte_special(pte_t pte)

{

	return 0;

}



static inline pte_t pte_wrprotect(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_WRITABLE;

	return pte;

}



static inline pte_t pte_rdprotect(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_READABLE;

	return pte;

}



static inline pte_t pte_exprotect(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_EXEC;

	return pte;

}



static inline pte_t pte_mkclean(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_DIRTY;

	return pte;

}



static inline pte_t pte_mkold(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_ACCESSED;

	return pte;

}



static inline pte_t pte_mkwrite(pte_t pte)

{

	pte_val(pte) |= CF_PAGE_WRITABLE;

	return pte;

}



static inline pte_t pte_mkread(pte_t pte)

{

	pte_val(pte) |= CF_PAGE_READABLE;

	return pte;

}



static inline pte_t pte_mkexec(pte_t pte)

{

	pte_val(pte) |= CF_PAGE_EXEC;

	return pte;

}



static inline pte_t pte_mkdirty(pte_t pte)

{

	pte_val(pte) |= CF_PAGE_DIRTY;

	return pte;

}



static inline pte_t pte_mkyoung(pte_t pte)

{

	pte_val(pte) |= CF_PAGE_ACCESSED;

	return pte;

}



static inline pte_t pte_mknocache(pte_t pte)

{

	pte_val(pte) |= 0x80 | (pte_val(pte) & ~0x40);

	return pte;

}



static inline pte_t pte_mkcache(pte_t pte)

{

	pte_val(pte) &= ~CF_PAGE_NOCACHE;

	return pte;

}



static inline pte_t pte_mkspecial(pte_t pte)

{

	return pte;

}



#define swapper_pg_dir kernel_pg_dir

extern pgd_t kernel_pg_dir[PTRS_PER_PGD];



/*

 * Find an entry in a pagetable directory.

 */

#define pgd_index(address)	((address) >> PGDIR_SHIFT)

#define pgd_offset(mm, address)	((mm)->pgd + pgd_index(address))



/*

 * Find an entry in a kernel pagetable directory.

 */

#define pgd_offset_k(address)	pgd_offset(&init_mm, address)



/*

 * Find an entry in the second-level pagetable.

 */

static inline pmd_t *pmd_offset(pgd_t *pgd, unsigned long address)

{

	return (pmd_t *) pgd;

}



/*

 * Find an entry in the third-level pagetable.

 */

#define __pte_offset(address)	((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))

#define pte_offset_kernel(dir, address) \

	((pte_t *) __pmd_page(*(dir)) + __pte_offset(address))



/*

 * Disable caching for page at given kernel virtual address.

 */

static inline void nocache_page(void *vaddr)

{

	pgd_t *dir;

	pmd_t *pmdp;

	pte_t *ptep;

	unsigned long addr = (unsigned long) vaddr;



	dir = pgd_offset_k(addr);

	pmdp = pmd_offset(dir, addr);

	ptep = pte_offset_kernel(pmdp, addr);

	*ptep = pte_mknocache(*ptep);

}



/*

 * Enable caching for page at given kernel virtual address.

 */

static inline void cache_page(void *vaddr)

{

	pgd_t *dir;

	pmd_t *pmdp;

	pte_t *ptep;

	unsigned long addr = (unsigned long) vaddr;



	dir = pgd_offset_k(addr);

	pmdp = pmd_offset(dir, addr);

	ptep = pte_offset_kernel(pmdp, addr);

	*ptep = pte_mkcache(*ptep);

}



#define PTE_FILE_MAX_BITS	21

#define PTE_FILE_SHIFT		11



static inline unsigned long pte_to_pgoff(pte_t pte)

{

	return pte_val(pte) >> PTE_FILE_SHIFT;

}



static inline pte_t pgoff_to_pte(unsigned pgoff)

{

	return __pte((pgoff << PTE_FILE_SHIFT) + CF_PAGE_FILE);

}



/*

 * Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e))

 */

#define __swp_type(x)		((x).val & 0xFF)

#define __swp_offset(x)		((x).val >> PTE_FILE_SHIFT)

#define __swp_entry(typ, off)	((swp_entry_t) { (typ) | \

					(off << PTE_FILE_SHIFT) })

#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })

#define __swp_entry_to_pte(x)	(__pte((x).val))



#define pmd_page(pmd)		(pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))



#define pte_offset_map(pmdp, addr) ((pte_t *)__pmd_page(*pmdp) + \

				       __pte_offset(addr))

#define pte_unmap(pte)		((void) 0)

#define pfn_pte(pfn, prot)	__pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))

#define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)



#endif	/* !__ASSEMBLY__ */

#endif	/* _MCF_PGTABLE_H */

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