release/src-rt-6.x.4708/linux/linux-2.6.36/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
  23 extern void clear_page(void *to);
  24 extern 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  */
  32 typedef struct { unsigned long pte; } pte_t;
  33 typedef struct { unsigned long pgd; } pgd_t;
  34 typedef struct { unsigned long pgprot; } pgprot_t;
  35 typedef 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 extern unsigned long memory_start, memory_end;
  46
  47 /* Pure 2^n version of get_order */
  48 static inline int get_order(unsigned long size)
  49 {
  50         unsigned lz;
  51
  52         size = (size - 1) >> PAGE_SHIFT;
  53         asm("clz %0, %1" : "=r"(lz) : "r"(size));
  54         return 32 - lz;
  55 }
  56
  57 #endif /* !__ASSEMBLY__ */
  58
  59 /*
  60  * The hardware maps the virtual addresses 0x80000000 -> 0x9fffffff
  61  * permanently to the physical addresses 0x00000000 -> 0x1fffffff when
  62  * segmentation is enabled. We want to make use of this in order to
  63  * minimize TLB pressure.
  64  */
  65 #define PAGE_OFFSET             (0x80000000UL)
  66
  67 /*
  68  * ALSA uses virt_to_page() on DMA pages, which I'm not entirely sure
  69  * is a good idea. Anyway, we can't simply subtract PAGE_OFFSET here
  70  * in that case, so we'll have to mask out the three most significant
  71  * bits of the address instead...
  72  *
  73  * What's the difference between __pa() and virt_to_phys() anyway?
  74  */
  75 #define __pa(x)         PHYSADDR(x)
  76 #define __va(x)         ((void *)(P1SEGADDR(x)))
  77
  78 #define MAP_NR(addr)    (((unsigned long)(addr) - PAGE_OFFSET) >> PAGE_SHIFT)
  79
  80 #define phys_to_page(phys)      (pfn_to_page(phys >> PAGE_SHIFT))
  81 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
  82
  83 #ifndef CONFIG_NEED_MULTIPLE_NODES
  84
  85 #define PHYS_PFN_OFFSET         (CONFIG_PHYS_OFFSET >> PAGE_SHIFT)
  86
  87 #define pfn_to_page(pfn)        (mem_map + ((pfn) - PHYS_PFN_OFFSET))
  88 #define page_to_pfn(page)       ((unsigned long)((page) - mem_map) + PHYS_PFN_OFFSET)
  89 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
  90 #endif /* CONFIG_NEED_MULTIPLE_NODES */
  91
  92 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
  93 #define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
  94
  95 #define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE |   \
  96                                  VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
  97
  98 /*
  99  * Memory above this physical address will be considered highmem.
 100  */
 101 #define HIGHMEM_START           0x20000000UL
 102
 103 #endif /* __ASM_AVR32_PAGE_H */