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
  51 struct page;
  52
  53 extern void clear_user_page(void *addr, unsigned long vaddr, struct page *page);
  54 extern 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  */
  60 typedef struct page *pgtable_t;
  61 typedef struct { unsigned long pte; } pte_t;
  62 typedef struct { unsigned long pgd; } pgd_t;
  63 typedef 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
  73 extern unsigned long memory_start;
  74 extern unsigned long memory_end;
  75 extern unsigned long memory_size;
  76
  77 extern 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
  89 static 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 */