LXR linux/arch/nios2/include/asm/page.h

   1/*
   2 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
   3 * Copyright (C) 2004 Microtronix Datacom Ltd.
   4 *
   5 * MMU support based on asm/page.h from mips which is:
   6 *
   7 * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
   8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   9 *
  10 * This file is subject to the terms and conditions of the GNU General Public
  11 * License.  See the file "COPYING" in the main directory of this archive
  12 * for more details.
  13 */
  14
  15#ifndef _ASM_NIOS2_PAGE_H
  16#define _ASM_NIOS2_PAGE_H
  17
  18#include <linux/pfn.h>
  19#include <linux/const.h>
  20
  21/*
  22 * PAGE_SHIFT determines the page size
  23 */
  24#define PAGE_SHIFT      12
  25#define PAGE_SIZE       (_AC(1, UL) << PAGE_SHIFT)
  26#define PAGE_MASK       (~(PAGE_SIZE - 1))
  27
  28/*
  29 * PAGE_OFFSET -- the first address of the first page of memory.
  30 */
  31#define PAGE_OFFSET     \
  32        (CONFIG_NIOS2_MEM_BASE + CONFIG_NIOS2_KERNEL_REGION_BASE)
  33
  34#ifndef __ASSEMBLY__
  35
  36/*
  37 * This gives the physical RAM offset.
  38 */
  39#define PHYS_OFFSET             CONFIG_NIOS2_MEM_BASE
  40
  41/*
  42 * It's normally defined only for FLATMEM config but it's
  43 * used in our early mem init code for all memory models.
  44 * So always define it.
  45 */
  46#define ARCH_PFN_OFFSET         PFN_UP(PHYS_OFFSET)
  47
  48#define clear_page(page)        memset((page), 0, PAGE_SIZE)
  49#define copy_page(to, from)     memcpy((to), (from), PAGE_SIZE)
  50
  51struct page;
  52
  53extern void clear_user_page(void *addr, unsigned long vaddr, struct page *page);
  54extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
  55                                struct page *to);
  56
  57/*
  58 * These are used to make use of C type-checking.
  59 */
  60typedef struct page *pgtable_t;
  61typedef struct { unsigned long pte; } pte_t;
  62typedef struct { unsigned long pgd; } pgd_t;
  63typedef struct { unsigned long pgprot; } pgprot_t;
  64
  65#define pte_val(x)      ((x).pte)
  66#define pgd_val(x)      ((x).pgd)
  67#define pgprot_val(x)   ((x).pgprot)
  68
  69#define __pte(x)        ((pte_t) { (x) })
  70#define __pgd(x)        ((pgd_t) { (x) })
  71#define __pgprot(x)     ((pgprot_t) { (x) })
  72
  73extern unsigned long memory_start;
  74extern unsigned long memory_end;
  75extern unsigned long memory_size;
  76
  77extern struct page *mem_map;
  78
  79# define __pa(x)                \
  80        ((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
  81# define __va(x)                \
  82        ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
  83
  84#define page_to_virt(page)      \
  85        ((void *)(((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET)
  86
  87# define pfn_to_kaddr(pfn)      __va((pfn) << PAGE_SHIFT)
  88
  89static inline bool pfn_valid(unsigned long pfn)
  90{
  91        /* avoid <linux/mm.h> include hell */
  92        extern unsigned long max_mapnr;
  93        unsigned long pfn_offset = ARCH_PFN_OFFSET;
  94
  95        return pfn >= pfn_offset && pfn < max_mapnr;
  96}
  97
  98# define virt_to_page(vaddr)    pfn_to_page(PFN_DOWN(virt_to_phys(vaddr)))
  99# define virt_addr_valid(vaddr) pfn_valid(PFN_DOWN(virt_to_phys(vaddr)))
 100
 101# define VM_DATA_DEFAULT_FLAGS  VM_DATA_FLAGS_NON_EXEC
 102
 103#include <asm-generic/memory_model.h>
 104
 105#include <asm-generic/getorder.h>
 106
 107#endif /* !__ASSEMBLY__ */
 108
 109#endif /* _ASM_NIOS2_PAGE_H */
 110