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/*

 * linux/include/asm-arm/proc-armv/pgtable.h

 *

 * Copyright (C) 1995, 1996, 1997 Russell King

 *

 * 12-01-1997   RMK     Altered flushing routines to use function pointers

 *                      now possible to combine ARM6, ARM7 and StrongARM versions.

 */

#ifndef __ASM_PROC_PGTABLE_H

#define __ASM_PROC_PGTABLE_H

#include <asm/arch/mmu.h>

#define LIBRARY_TEXT_START 0x0c000000

/*

 * Cache flushing...

 */

#define flush_cache_all()                                               \

        processor.u.armv3v4._flush_cache_all()

#define flush_cache_mm(_mm)                                             \

        do {                                                            \

                if ((_mm) == current->mm)                               \

                        processor.u.armv3v4._flush_cache_all();         \

        } while (0)

#define flush_cache_range(_mm,_start,_end)                              \

        do {                                                            \

                if ((_mm) == current->mm)                               \

                        processor.u.armv3v4._flush_cache_area           \

                                ((_start), (_end), 1);                  \

        } while (0)

#define flush_cache_page(_vma,_vmaddr)                                  \

        do {                                                            \

                if ((_vma)->vm_mm == current->mm)                       \

                        processor.u.armv3v4._flush_cache_area           \

                                ((_vmaddr), (_vmaddr) + PAGE_SIZE,      \

                                 ((_vma)->vm_flags & VM_EXEC) ? 1 : 0);  \

        } while (0)

/*

 * We don't have a mem map cache...

 */

#define update_mm_cache_all()                   do { } while (0)

#define update_mm_cache_task(tsk)               do { } while (0)

#define update_mm_cache_mm(mm)                  do { } while (0)

#define update_mm_cache_mm_addr(mm,addr,pte)    do { } while (0)

/*

 * This flushes back any buffered write data.  We have to clean and flush the entries

 * in the cache for this page.  Is it necessary to invalidate the I-cache?

 */

#define flush_page_to_ram(_page)                                        \

        processor.u.armv3v4._flush_ram_page ((_page) & PAGE_MASK);

/*

 * Make the page uncacheable (must flush page beforehand).

 */

#define uncache_page(_page)                                             \

        processor.u.armv3v4._flush_ram_page ((_page) & PAGE_MASK);

/*

 * TLB flushing:

 *

 *  - flush_tlb() flushes the current mm struct TLBs

 *  - flush_tlb_all() flushes all processes TLBs

 *  - flush_tlb_mm(mm) flushes the specified mm context TLB's

 *  - flush_tlb_page(vma, vmaddr) flushes one page

 *  - flush_tlb_range(mm, start, end) flushes a range of pages

 *

 * GCC uses conditional instructions, and expects the assembler code to do so as well.

 *

 * We drain the write buffer in here to ensure that the page tables in ram

 * are really up to date.  It is more efficient to do this here...

 */

#define flush_tlb() flush_tlb_all()

#define flush_tlb_all()                                                         \

        processor.u.armv3v4._flush_tlb_all()

#define flush_tlb_mm(_mm)                                                       \

        do {                                                                    \

                if ((_mm) == current->mm)                                       \

                        processor.u.armv3v4._flush_tlb_all();                   \

        } while (0)

#define flush_tlb_range(_mm,_start,_end)                                        \

        do {                                                                    \

                if ((_mm) == current->mm)                                       \

                        processor.u.armv3v4._flush_tlb_area                     \

                                ((_start), (_end), 1);                          \

        } while (0)

#define flush_tlb_page(_vma,_vmaddr)                                            \

        do {                                                                    \

                if ((_vma)->vm_mm == current->mm)                               \

                        processor.u.armv3v4._flush_tlb_area                     \

                                ((_vmaddr), (_vmaddr) + PAGE_SIZE,              \

                                 ((_vma)->vm_flags & VM_EXEC) ? 1 : 0);          \

        } while (0)

/*

 * Since the page tables are in cached memory, we need to flush the dirty

 * data cached entries back before we flush the tlb...  This is also useful

 * to flush out the SWI instruction for signal handlers...

 */

#define __flush_entry_to_ram(entry)                                             \

        processor.u.armv3v4._flush_cache_entry((unsigned long)(entry))

#define __flush_pte_to_ram(entry)                                               \

        processor.u.armv3v4._flush_cache_pte((unsigned long)(entry))

/* PMD_SHIFT determines the size of the area a second-level page table can map */

#define PMD_SHIFT       20

#define PMD_SIZE        (1UL << PMD_SHIFT)

#define PMD_MASK        (~(PMD_SIZE-1))

/* PGDIR_SHIFT determines what a third-level page table entry can map */

#define PGDIR_SHIFT     20

#define PGDIR_SIZE      (1UL << PGDIR_SHIFT)

#define PGDIR_MASK      (~(PGDIR_SIZE-1))

/*

 * entries per page directory level: the sa110 is two-level, so

 * we don't really have any PMD directory physically.

 */

#define PTRS_PER_PTE    256

#define PTRS_PER_PMD    1

#define PTRS_PER_PGD    4096

/* Just any arbitrary offset to the start of the vmalloc VM area: the

 * current 8MB value just means that there will be a 8MB "hole" after the

 * physical memory until the kernel virtual memory starts.  That means that

 * any out-of-bounds memory accesses will hopefully be caught.

 * The vmalloc() routines leaves a hole of 4kB between each vmalloced

 * area for the same reason. ;)

 */

#define VMALLOC_OFFSET    (8*1024*1024)

#define VMALLOC_START     ((high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))

#define VMALLOC_VMADDR(x) ((unsigned long)(x))

/* PMD types (actually level 1 descriptor) */

#define PMD_TYPE_MASK           0x0003

#define PMD_TYPE_FAULT          0x0000

#define PMD_TYPE_TABLE          0x0001

#define PMD_TYPE_SECT           0x0002

#define PMD_UPDATABLE           0x0010

#define PMD_SECT_CACHEABLE      0x0008

#define PMD_SECT_BUFFERABLE     0x0004

#define PMD_SECT_AP_WRITE       0x0400

#define PMD_SECT_AP_READ        0x0800

#define PMD_DOMAIN(x)           ((x) << 5)

/* PTE types (actually level 2 descriptor) */

#define PTE_TYPE_MASK   0x0003

#define PTE_TYPE_FAULT  0x0000

#define PTE_TYPE_LARGE  0x0001

#define PTE_TYPE_SMALL  0x0002

#define PTE_AP_READ     0x0aa0

#define PTE_AP_WRITE    0x0550

#define PTE_CACHEABLE   0x0008

#define PTE_BUFFERABLE  0x0004

/* Domains */

#define DOMAIN_KERNEL   0

#define _PAGE_CHG_MASK  (0xfffff00c | PTE_TYPE_MASK)

/*

 * We define the bits in the page tables as follows:

 *  PTE_BUFFERABLE      page is dirty

 *  PTE_AP_WRITE        page is writable

 *  PTE_AP_READ         page is a young (unsetting this causes faults for any access)

 *

 * Any page that is mapped in is assumed to be readable...

 */

#define PAGE_NONE       __pgprot(PTE_TYPE_SMALL)

#define PAGE_SHARED     __pgprot(PTE_TYPE_SMALL | PTE_CACHEABLE | PTE_AP_READ | PTE_AP_WRITE)

#define PAGE_COPY       __pgprot(PTE_TYPE_SMALL | PTE_CACHEABLE | PTE_AP_READ)

#define PAGE_READONLY   __pgprot(PTE_TYPE_SMALL | PTE_CACHEABLE | PTE_AP_READ)

#define PAGE_KERNEL     __pgprot(PTE_TYPE_SMALL | PTE_CACHEABLE | PTE_BUFFERABLE | PTE_AP_WRITE)

#define _PAGE_TABLE     (PMD_TYPE_TABLE | PMD_DOMAIN(DOMAIN_KERNEL))

/*

 * The arm can't do page protection for execute, and considers that the same are read.

 * 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

#undef TEST_VERIFY_AREA

/*

 * BAD_PAGETABLE is used when we need a bogus page-table, while

 * BAD_PAGE is used for a bogus page.

 *

 * ZERO_PAGE is a global shared page that is always zero: used

 * for zero-mapped memory areas etc..

 */

extern pte_t __bad_page(void);

extern pte_t * __bad_pagetable(void);

extern unsigned long *empty_zero_page;

#define BAD_PAGETABLE __bad_pagetable()

#define BAD_PAGE __bad_page()

#define ZERO_PAGE ((unsigned long) empty_zero_page)

/* number of bits that fit into a memory pointer */

#define BYTES_PER_PTR                   (sizeof(unsigned long))

#define BITS_PER_PTR                    (8*BYTES_PER_PTR)

/* to align the pointer to a pointer address */

#define PTR_MASK                        (~(sizeof(void*)-1))

/* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */

#define SIZEOF_PTR_LOG2                 2

/* to find an entry in a page-table */

#define PAGE_PTR(address) \

((unsigned long)(address)>>(PAGE_SHIFT-SIZEOF_PTR_LOG2)&PTR_MASK&~PAGE_MASK)

/* to set the page-dir */

#define SET_PAGE_DIR(tsk,pgdir)                                 \

do {                                                            \

        tsk->tss.memmap = __virt_to_phys((unsigned long)pgdir); \

        if ((tsk) == current)                                   \

                __asm__ __volatile__(                           \

                "mcr%?  p15, 0, %0, c2, c0, 0\n"                \

                : : "r" (tsk->tss.memmap));                     \

} while (0)

extern __inline__ int pte_none(pte_t pte)

{

        return !pte_val(pte);

}

#define pte_clear(ptep) set_pte(ptep, __pte(0))

extern __inline__ int pte_present(pte_t pte)

{

        switch (pte_val(pte) & PTE_TYPE_MASK) {

        case PTE_TYPE_LARGE:

        case PTE_TYPE_SMALL:

                return 1;

        default:

                return 0;

        }

}

extern __inline__ int pmd_none(pmd_t pmd)

{

        return !pmd_val(pmd);

}

#define pmd_clear(pmdp) set_pmd(pmdp, __pmd(0))

extern __inline__ int pmd_bad(pmd_t pmd)

{

        switch (pmd_val(pmd) & PMD_TYPE_MASK) {

        case PMD_TYPE_FAULT:

        case PMD_TYPE_TABLE:

                return 0;

        default:

                return 1;

        }

}

extern __inline__ int pmd_present(pmd_t pmd)

{

        switch (pmd_val(pmd) & PMD_TYPE_MASK) {

        case PMD_TYPE_TABLE:

                return 1;

        default:

                return 0;

        }

}

/*

 * The "pgd_xxx()" functions here are trivial for a folded two-level

 * setup: the pgd is never bad, and a pmd always exists (as it's folded

 * into the pgd entry)

 */

#define pgd_none(pgd)           (0)

#define pgd_bad(pgd)            (0)

#define pgd_present(pgd)        (1)

#define pgd_clear(pgdp)

/*

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

 * Undefined behaviour if not..

 */

#define pte_read(pte)           (1)

#define pte_exec(pte)           (1)

extern __inline__ int pte_write(pte_t pte)

{

        return pte_val(pte) & PTE_AP_WRITE;

}

extern __inline__ int pte_cacheable(pte_t pte)

{

        return pte_val(pte) & PTE_CACHEABLE;

}

extern __inline__ int pte_dirty(pte_t pte)

{

        return pte_val(pte) & PTE_BUFFERABLE;

}

extern __inline__ int pte_young(pte_t pte)

{

        return pte_val(pte) & PTE_AP_READ;

}

extern __inline__ pte_t pte_wrprotect(pte_t pte)

{

        pte_val(pte) &= ~PTE_AP_WRITE;

        return pte;

}

extern __inline__ pte_t pte_nocache(pte_t pte)

{

        pte_val(pte) &= ~PTE_CACHEABLE;

        return pte;

}

extern __inline__ pte_t pte_mkclean(pte_t pte)

{

        pte_val(pte) &= ~PTE_BUFFERABLE;

        return pte;

}

extern __inline__ pte_t pte_mkold(pte_t pte)

{

        pte_val(pte) &= ~PTE_AP_READ;

        return pte;

}

extern __inline__ pte_t pte_mkwrite(pte_t pte)

{

        pte_val(pte) |= PTE_AP_WRITE;

        return pte;

}

extern __inline__ pte_t pte_mkdirty(pte_t pte)

{

        pte_val(pte) |= PTE_BUFFERABLE;

        return pte;

}

extern __inline__ pte_t pte_mkyoung(pte_t pte)

{

        pte_val(pte) |= PTE_AP_READ;

        return pte;

}

/*

 * The following are unable to be implemented on this MMU

 */

#if 0

extern __inline__ pte_t pte_rdprotect(pte_t pte)

{

        pte_val(pte) &= ~(PTE_CACHEABLE|PTE_AP_READ);

        return pte;

}

extern __inline__ pte_t pte_exprotect(pte_t pte)

{

        pte_val(pte) &= ~(PTE_CACHEABLE|PTE_AP_READ);

        return pte;

}

extern __inline__ pte_t pte_mkread(pte_t pte)

{

        pte_val(pte) |= PTE_CACHEABLE;

        return pte;

}

extern __inline__ pte_t pte_mkexec(pte_t pte)

{

        pte_val(pte) |= PTE_CACHEABLE;

        return pte;

}

#endif

/*

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

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

 */

extern __inline__ pte_t mk_pte(unsigned long page, pgprot_t pgprot)

{

        pte_t pte;

        pte_val(pte) = __virt_to_phys(page) | pgprot_val(pgprot);

        return pte;

}

extern __inline__ pte_t pte_modify(pte_t pte, pgprot_t newprot)

{

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

        return pte;

}

extern __inline__ void set_pte(pte_t *pteptr, pte_t pteval)

{

        *pteptr = pteval;

        __flush_pte_to_ram(pteptr);

}

extern __inline__ unsigned long pte_page(pte_t pte)

{

        return __phys_to_virt(pte_val(pte) & PAGE_MASK);

}

extern __inline__ pmd_t mk_pmd(pte_t *ptep)

{

        pmd_t pmd;

        pmd_val(pmd) = __virt_to_phys((unsigned long)ptep) | _PAGE_TABLE;

        return pmd;

}

#if 1

#define set_pmd(pmdp,pmd) processor.u.armv3v4._set_pmd(pmdp,pmd)

#else

extern __inline__ void set_pmd(pmd_t *pmdp, pmd_t pmd)

{

        *pmdp = pmd;

        __flush_pte_to_ram(pmdp);

}

#endif

extern __inline__ unsigned long pmd_page(pmd_t pmd)

{

        return __phys_to_virt(pmd_val(pmd) & 0xfffffc00);

}

/* to find an entry in a page-table-directory */

extern __inline__ pgd_t * pgd_offset(struct mm_struct * mm, unsigned long address)

{

        return mm->pgd + (address >> PGDIR_SHIFT);

}

/* Find an entry in the second-level page table.. */

#define pmd_offset(dir, address) ((pmd_t *)(dir))

/* Find an entry in the third-level page table.. */

extern __inline__ pte_t * pte_offset(pmd_t * dir, unsigned long address)

{

        return (pte_t *) pmd_page(*dir) + ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));

}

extern unsigned long get_small_page(int priority);

extern void free_small_page(unsigned long page);

/*

 * Allocate and free page tables. The xxx_kernel() versions are

 * used to allocate a kernel page table - this turns on ASN bits

 * if any.

 */

extern __inline__ void pte_free_kernel(pte_t * pte)

{

        free_small_page((unsigned long) pte);

}

extern const char bad_pmd_string[];

extern __inline__ pte_t * pte_alloc_kernel(pmd_t *pmd, unsigned long address)

{

        address = (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);

        if (pmd_none(*pmd)) {

                pte_t *page = (pte_t *) get_small_page(GFP_KERNEL);

                if (pmd_none(*pmd)) {

                        if (page) {

                                memzero (page, PTRS_PER_PTE * BYTES_PER_PTR);

                                set_pmd(pmd, mk_pmd(page));

                                return page + address;

                        }

                        set_pmd(pmd, mk_pmd(BAD_PAGETABLE));

                        return NULL;

                }

                free_small_page((unsigned long) page);

        }

        if (pmd_bad(*pmd)) {

                printk(bad_pmd_string, pmd_val(*pmd));

                set_pmd(pmd, mk_pmd(BAD_PAGETABLE));

                return NULL;

        }

        return (pte_t *) pmd_page(*pmd) + address;

}

/*

 * allocating and freeing a pmd is trivial: the 1-entry pmd is

 * inside the pgd, so has no extra memory associated with it.

 */

#define pmd_free_kernel(pmdp) pmd_val(*(pmdp)) = 0;

#define pmd_alloc_kernel(pgdp, address) ((pmd_t *)(pgdp))

extern __inline__ void pte_free(pte_t * pte)

{

        free_small_page((unsigned long) pte);

}

extern __inline__ pte_t * pte_alloc(pmd_t * pmd, unsigned long address)

{

        address = (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);

        if (pmd_none(*pmd)) {

                pte_t *page = (pte_t *) get_small_page(GFP_KERNEL);

                if (pmd_none(*pmd)) {

                        if (page) {

                                memzero (page, PTRS_PER_PTE * BYTES_PER_PTR);

                                set_pmd(pmd, mk_pmd(page));

                                return page + address;

                        }

                        set_pmd(pmd, mk_pmd(BAD_PAGETABLE));

                        return NULL;

                }

                free_small_page ((unsigned long) page);

        }

        if (pmd_bad(*pmd)) {

                printk(bad_pmd_string, pmd_val(*pmd));

                set_pmd(pmd, mk_pmd(BAD_PAGETABLE));

                return NULL;

        }

        return (pte_t *) pmd_page(*pmd) + address;

}

/*

 * allocating and freeing a pmd is trivial: the 1-entry pmd is

 * inside the pgd, so has no extra memory associated with it.

 */

#define pmd_free(pmdp) pmd_val(*(pmdp)) = 0;

#define pmd_alloc(pgdp, address) ((pmd_t *)(pgdp))

/*

 * Free a page directory.  Takes the virtual address.

 */

extern __inline__ void pgd_free(pgd_t * pgd)

{

        free_pages((unsigned long) pgd, 2);

}

/*

 * Allocate a new page directory.  Return the virtual address of it.

 */

extern __inline__ pgd_t * pgd_alloc(void)

{

        unsigned long pgd;

        /*

         * need to get a 16k page for level 1

         */

        pgd = __get_free_pages(GFP_KERNEL,2,0);

        if (pgd)

                memzero ((void *)pgd, PTRS_PER_PGD * BYTES_PER_PTR);

        return (pgd_t *)pgd;

}

extern pgd_t swapper_pg_dir[PTRS_PER_PGD];

/*

 * The sa110 doesn't have any external MMU info: the kernel page

 * tables contain all the necessary information.

 */

extern __inline__ void update_mmu_cache(struct vm_area_struct * vma,

        unsigned long address, pte_t pte)

{

}

#define SWP_TYPE(entry) (((entry) >> 2) & 0x7f)

#define SWP_OFFSET(entry) ((entry) >> 9)

#define SWP_ENTRY(type,offset) (((type) << 2) | ((offset) << 9))

#endif /* __ASM_PROC_PAGE_H */