include/asm-arm/memory.h

   1 /*
   2  *  linux/include/asm-arm/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  * Allow for constants defined here to be used from assembly code
  17  * by prepending the UL suffix only with actual C code compilation.
  18  */
  19 #ifndef __ASSEMBLY__
  20 #define UL(x) (x##UL)
  21 #else
  22 #define UL(x) (x)
  23 #endif
  24
  25 #include <linux/config.h>
  26 #include <linux/compiler.h>
  27 #include <asm/arch/memory.h>
  28
  29 #ifndef TASK_SIZE
  30 /*
  31  * TASK_SIZE - the maximum size of a user space task.
  32  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
  33  */
  34 #define TASK_SIZE               UL(0xbf000000)
  35 #define TASK_UNMAPPED_BASE      UL(0x40000000)
  36 #endif
  37
  38 /*
  39  * The maximum size of a 26-bit user space task.
  40  */
  41 #define TASK_SIZE_26            UL(0x04000000)
  42
  43 /*
  44  * Page offset: 3GB
  45  */
  46 #ifndef PAGE_OFFSET
  47 #define PAGE_OFFSET             UL(0xc0000000)
  48 #endif
  49
  50 /*
  51  * Physical vs virtual RAM address space conversion.  These are
  52  * private definitions which should NOT be used outside memory.h
  53  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  54  */
  55 #ifndef __virt_to_phys
  56 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
  57 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
  58 #endif
  59
  60 /*
  61  * The module space lives between the addresses given by TASK_SIZE
  62  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  63  */
  64 #define MODULE_END      (PAGE_OFFSET)
  65 #define MODULE_START    (MODULE_END - 16*1048576)
  66
  67 #if TASK_SIZE > MODULE_START
  68 #error Top of user space clashes with start of module space
  69 #endif
  70
  71 /*
  72  * The XIP kernel gets mapped at the bottom of the module vm area.
  73  * Since we use sections to map it, this macro replaces the physical address
  74  * with its virtual address while keeping offset from the base section.
  75  */
  76 #define XIP_VIRT_ADDR(physaddr)  (MODULE_START + ((physaddr) & 0x000fffff))
  77
  78 #ifndef __ASSEMBLY__
  79
  80 /*
  81  * The DMA mask corresponding to the maximum bus address allocatable
  82  * using GFP_DMA.  The default here places no restriction on DMA
  83  * allocations.  This must be the smallest DMA mask in the system,
  84  * so a successful GFP_DMA allocation will always satisfy this.
  85  */
  86 #ifndef ISA_DMA_THRESHOLD
  87 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
  88 #endif
  89
  90 #ifndef arch_adjust_zones
  91 #define arch_adjust_zones(node,size,holes) do { } while (0)
  92 #endif
  93
  94 /*
  95  * PFNs are used to describe any physical page; this means
  96  * PFN 0 == physical address 0.
  97  *
  98  * This is the PFN of the first RAM page in the kernel
  99  * direct-mapped view.  We assume this is the first page
 100  * of RAM in the mem_map as well.
 101  */
 102 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 103
 104 /*
 105  * These are *only* valid on the kernel direct mapped RAM memory.
 106  * Note: Drivers should NOT use these.  They are the wrong
 107  * translation for translating DMA addresses.  Use the driver
 108  * DMA support - see dma-mapping.h.
 109  */
 110 static inline unsigned long virt_to_phys(void *x)
 111 {
 112         return __virt_to_phys((unsigned long)(x));
 113 }
 114
 115 static inline void *phys_to_virt(unsigned long x)
 116 {
 117         return (void *)(__phys_to_virt((unsigned long)(x)));
 118 }
 119
 120 /*
 121  * Drivers should NOT use these either.
 122  */
 123 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 124 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 125 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 126
 127 /*
 128  * Virtual <-> DMA view memory address translations
 129  * Again, these are *only* valid on the kernel direct mapped RAM
 130  * memory.  Use of these is *deprecated* (and that doesn't mean
 131  * use the __ prefixed forms instead.)  See dma-mapping.h.
 132  */
 133 static inline __deprecated unsigned long virt_to_bus(void *x)
 134 {
 135         return __virt_to_bus((unsigned long)x);
 136 }
 137
 138 static inline __deprecated void *bus_to_virt(unsigned long x)
 139 {
 140         return (void *)__bus_to_virt(x);
 141 }
 142
 143 /*
 144  * Conversion between a struct page and a physical address.
 145  *
 146  * Note: when converting an unknown physical address to a
 147  * struct page, the resulting pointer must be validated
 148  * using VALID_PAGE().  It must return an invalid struct page
 149  * for any physical address not corresponding to a system
 150  * RAM address.
 151  *
 152  *  page_to_pfn(page)   convert a struct page * to a PFN number
 153  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 154  *  pfn_valid(pfn)      indicates whether a PFN number is valid
 155  *
 156  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 157  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 158  */
 159 #ifndef CONFIG_DISCONTIGMEM
 160
 161 #define page_to_pfn(page)       (((page) - mem_map) + PHYS_PFN_OFFSET)
 162 #define pfn_to_page(pfn)        ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
 163 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
 164
 165 #define virt_to_page(kaddr)     (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
 166 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 167
 168 #define PHYS_TO_NID(addr)       (0)
 169
 170 #else /* CONFIG_DISCONTIGMEM */
 171
 172 /*
 173  * This is more complex.  We have a set of mem_map arrays spread
 174  * around in memory.
 175  */
 176 #include <linux/numa.h>
 177
 178 #define page_to_pfn(page)                                       \
 179         (( (page) - page_zone(page)->zone_mem_map)              \
 180           + page_zone(page)->zone_start_pfn)
 181
 182 #define pfn_to_page(pfn)                                        \
 183         (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
 184
 185 #define pfn_valid(pfn)                                          \
 186         ({                                                      \
 187                 unsigned int nid = PFN_TO_NID(pfn);             \
 188                 int valid = nid < MAX_NUMNODES;                 \
 189                 if (valid) {                                    \
 190                         pg_data_t *node = NODE_DATA(nid);       \
 191                         valid = (pfn - node->node_start_pfn) <  \
 192                                 node->node_spanned_pages;       \
 193                 }                                               \
 194                 valid;                                          \
 195         })
 196
 197 #define virt_to_page(kaddr)                                     \
 198         (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
 199
 200 #define virt_addr_valid(kaddr)  (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
 201
 202 /*
 203  * Common discontigmem stuff.
 204  *  PHYS_TO_NID is used by the ARM kernel/setup.c
 205  */
 206 #define PHYS_TO_NID(addr)       PFN_TO_NID((addr) >> PAGE_SHIFT)
 207
 208 #endif /* !CONFIG_DISCONTIGMEM */
 209
 210 /*
 211  * For BIO.  "will die".  Kill me when bio_to_phys() and bvec_to_phys() die.
 212  */
 213 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 214
 215 /*
 216  * Optional device DMA address remapping. Do _not_ use directly!
 217  * We should really eliminate virt_to_bus() here - it's deprecated.
 218  */
 219 #ifndef __arch_page_to_dma
 220 #define page_to_dma(dev, page)          ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
 221 #define dma_to_virt(dev, addr)          ((void *)__bus_to_virt(addr))
 222 #define virt_to_dma(dev, addr)          ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
 223 #else
 224 #define page_to_dma(dev, page)          (__arch_page_to_dma(dev, page))
 225 #define dma_to_virt(dev, addr)          (__arch_dma_to_virt(dev, addr))
 226 #define virt_to_dma(dev, addr)          (__arch_virt_to_dma(dev, addr))
 227 #endif
 228
 229 #endif
 230
 231 #endif