linux/arch/m68k/include/asm/mcf_pgtable.h
Alexander Stein 57e00098cc m68k: Add shared bit to Coldfire kernel page entries
We had problems accessing our NOR flash trough mtd. The system always got
stuck at attaching UBI using ubiattach if booted from NFS or after mounting
squashfs as rootfs directly from NOR flash.
After some testing of the new changes introduced from v3.2-rc1 to v3.2-rc7
we had to apply the following patch to get mtd working again.

[gerg: The problem was ultimately caused by allocated kernel pages not having
the shared (SG) bit set. Without the SG bit set the MMU will look for page
matches incorporating the ASID as well. Things like module regions allocated
using vmalloc would fault when other processes run. ]

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2012-02-07 11:04:00 +10:00

427 lines
10 KiB
C

#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 \
| CF_PAGE_SHARED)
#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 */