LXR linux/arch/avr32/include/asm/page.h

   1/*
   2 * Copyright (C) 2004-2006 Atmel Corporation
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 */
   8#ifndef __ASM_AVR32_PAGE_H
   9#define __ASM_AVR32_PAGE_H
  10
  11#include <linux/const.h>
  12
  13/* PAGE_SHIFT determines the page size */
  14#define PAGE_SHIFT      12
  15#define PAGE_SIZE       (_AC(1, UL) << PAGE_SHIFT)
  16#define PAGE_MASK       (~(PAGE_SIZE-1))
  17#define PTE_MASK        PAGE_MASK
  18
  19#ifndef __ASSEMBLY__
  20
  21#include <asm/addrspace.h>
  22
  23extern void clear_page(void *to);
  24extern void copy_page(void *to, void *from);
  25
  26#define clear_user_page(page, vaddr, pg)        clear_page(page)
  27#define copy_user_page(to, from, vaddr, pg)     copy_page(to, from)
  28
  29/*
  30 * These are used to make use of C type-checking..
  31 */
  32typedef struct { unsigned long pte; } pte_t;
  33typedef struct { unsigned long pgd; } pgd_t;
  34typedef struct { unsigned long pgprot; } pgprot_t;
  35typedef struct page *pgtable_t;
  36
  37#define pte_val(x)              ((x).pte)
  38#define pgd_val(x)              ((x).pgd)
  39#define pgprot_val(x)           ((x).pgprot)
  40
  41#define __pte(x)                ((pte_t) { (x) })
  42#define __pgd(x)                ((pgd_t) { (x) })
  43#define __pgprot(x)             ((pgprot_t) { (x) })
  44
  45/* FIXME: These should be removed soon */
  46extern unsigned long memory_start, memory_end;
  47
  48/* Pure 2^n version of get_order */
  49static inline int get_order(unsigned long size)
  50{
  51        unsigned lz;
  52
  53        size = (size - 1) >> PAGE_SHIFT;
  54        asm("clz %0, %1" : "=r"(lz) : "r"(size));
  55        return 32 - lz;
  56}
  57
  58#endif /* !__ASSEMBLY__ */
  59
  60/*
  61 * The hardware maps the virtual addresses 0x80000000 -> 0x9fffffff
  62 * permanently to the physical addresses 0x00000000 -> 0x1fffffff when
  63 * segmentation is enabled. We want to make use of this in order to
  64 * minimize TLB pressure.
  65 */
  66#define PAGE_OFFSET             (0x80000000UL)
  67
  68/*
  69 * ALSA uses virt_to_page() on DMA pages, which I'm not entirely sure
  70 * is a good idea. Anyway, we can't simply subtract PAGE_OFFSET here
  71 * in that case, so we'll have to mask out the three most significant
  72 * bits of the address instead...
  73 *
  74 * What's the difference between __pa() and virt_to_phys() anyway?
  75 */
  76#define __pa(x)         PHYSADDR(x)
  77#define __va(x)         ((void *)(P1SEGADDR(x)))
  78
  79#define MAP_NR(addr)    (((unsigned long)(addr) - PAGE_OFFSET) >> PAGE_SHIFT)
  80
  81#define phys_to_page(phys)      (pfn_to_page(phys >> PAGE_SHIFT))
  82#define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
  83
  84#ifndef CONFIG_NEED_MULTIPLE_NODES
  85
  86#define PHYS_PFN_OFFSET         (CONFIG_PHYS_OFFSET >> PAGE_SHIFT)
  87
  88#define pfn_to_page(pfn)        (mem_map + ((pfn) - PHYS_PFN_OFFSET))
  89#define page_to_pfn(page)       ((unsigned long)((page) - mem_map) + PHYS_PFN_OFFSET)
  90#define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
  91#endif /* CONFIG_NEED_MULTIPLE_NODES */
  92
  93#define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
  94#define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
  95
  96#define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE |   \
  97                                 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
  98
  99/*
 100 * Memory above this physical address will be considered highmem.
 101 */
 102#define HIGHMEM_START           0x20000000UL
 103
 104#endif /* __ASM_AVR32_PAGE_H */
 105