include/asm-arm26/memory.h

   1 /*
   2  *  linux/include/asm-arm26/memory.h
   3  *
   4  *  Copyright (C) 2000-2002 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  *  Note: this file should not be included by non-asm/.h files
  11  */
  12 #ifndef __ASM_ARM_MEMORY_H
  13 #define __ASM_ARM_MEMORY_H
  14
  15 /*
  16  * User space: 26MB
  17  */
  18 #define TASK_SIZE       (0x01a00000UL)
  19
  20 /*
  21  * This decides where the kernel will search for a free chunk of vm
  22  * space during mmap's.
  23  */
  24 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
  25
  26 /*
  27  * Page offset: 32MB
  28  */
  29 #define PAGE_OFFSET     (0x02000000UL)
  30 #define PHYS_OFFSET     (0x02000000UL)
  31
  32 #define PHYS_TO_NID(addr)       (0)
  33
  34 /*
  35  * PFNs are used to describe any physical page; this means
  36  * PFN 0 == physical address 0.
  37  *
  38  * This is the PFN of the first RAM page in the kernel
  39  * direct-mapped view.  We assume this is the first page
  40  * of RAM in the mem_map as well.
  41  */
  42 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
  43
  44 /*
  45  * These are *only* valid on the kernel direct mapped RAM memory.
  46  */
  47 static inline unsigned long virt_to_phys(void *x)
  48 {
  49         return (unsigned long)x;
  50 }
  51
  52 static inline void *phys_to_virt(unsigned long x)
  53 {
  54         return (void *)((unsigned long)x);
  55 }
  56
  57 #define __pa(x)                 (unsigned long)(x)
  58 #define __va(x)                 ((void *)(unsigned long)(x))
  59
  60 /*
  61  * Virtual <-> DMA view memory address translations
  62  * Again, these are *only* valid on the kernel direct mapped RAM
  63  * memory.  Use of these is *depreciated*.
  64  */
  65 #define virt_to_bus(x)          ((unsigned long)(x))
  66 #define bus_to_virt(x)          ((void *)((unsigned long)(x)))
  67
  68 /*
  69  * Conversion between a struct page and a physical address.
  70  *
  71  * Note: when converting an unknown physical address to a
  72  * struct page, the resulting pointer must be validated
  73  * using VALID_PAGE().  It must return an invalid struct page
  74  * for any physical address not corresponding to a system
  75  * RAM address.
  76  *
  77  *  page_to_pfn(page)   convert a struct page * to a PFN number
  78  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
  79  *  pfn_valid(pfn)      indicates whether a PFN number is valid
  80  *
  81  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
  82  *  virt_addr_valid(k)  indicates whether a virtual address is valid
  83  */
  84 #define page_to_pfn(page)       (((page) - mem_map) + PHYS_PFN_OFFSET)
  85 #define pfn_to_page(pfn)        ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
  86 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
  87
  88 #define virt_to_page(kaddr)     (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
  89 #define virt_addr_valid(kaddr)  ((int)(kaddr) >= PAGE_OFFSET && (int)(kaddr) < (unsigned long)high_memory)
  90
  91 /*
  92  * For BIO.  "will die".  Kill me when bio_to_phys() and bvec_to_phys() die.
  93  */
  94 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
  95
  96 /*
  97  * We should really eliminate virt_to_bus() here - it's depreciated.
  98  */
  99 #define page_to_bus(page)       (page_address(page))
 100
 101 #endif