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  * Convert a physical address to a Page Frame Number and back
  62  */
  63 #define __phys_to_pfn(paddr)    ((paddr) >> PAGE_SHIFT)
  64 #define __pfn_to_phys(pfn)      ((pfn) << PAGE_SHIFT)
  65
  66 /*
  67  * The module space lives between the addresses given by TASK_SIZE
  68  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  69  */
  70 #define MODULE_END      (PAGE_OFFSET)
  71 #define MODULE_START    (MODULE_END - 16*1048576)
  72
  73 #if TASK_SIZE > MODULE_START
  74 #error Top of user space clashes with start of module space
  75 #endif
  76
  77 /*
  78  * The XIP kernel gets mapped at the bottom of the module vm area.
  79  * Since we use sections to map it, this macro replaces the physical address
  80  * with its virtual address while keeping offset from the base section.
  81  */
  82 #define XIP_VIRT_ADDR(physaddr)  (MODULE_START + ((physaddr) & 0x000fffff))
  83
  84 #ifndef __ASSEMBLY__
  85
  86 /*
  87  * The DMA mask corresponding to the maximum bus address allocatable
  88  * using GFP_DMA.  The default here places no restriction on DMA
  89  * allocations.  This must be the smallest DMA mask in the system,
  90  * so a successful GFP_DMA allocation will always satisfy this.
  91  */
  92 #ifndef ISA_DMA_THRESHOLD
  93 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
  94 #endif
  95
  96 #ifndef arch_adjust_zones
  97 #define arch_adjust_zones(node,size,holes) do { } while (0)
  98 #endif
  99
 100 /*
 101  * PFNs are used to describe any physical page; this means
 102  * PFN 0 == physical address 0.
 103  *
 104  * This is the PFN of the first RAM page in the kernel
 105  * direct-mapped view.  We assume this is the first page
 106  * of RAM in the mem_map as well.
 107  */
 108 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 109
 110 /*
 111  * These are *only* valid on the kernel direct mapped RAM memory.
 112  * Note: Drivers should NOT use these.  They are the wrong
 113  * translation for translating DMA addresses.  Use the driver
 114  * DMA support - see dma-mapping.h.
 115  */
 116 static inline unsigned long virt_to_phys(void *x)
 117 {
 118         return __virt_to_phys((unsigned long)(x));
 119 }
 120
 121 static inline void *phys_to_virt(unsigned long x)
 122 {
 123         return (void *)(__phys_to_virt((unsigned long)(x)));
 124 }
 125
 126 /*
 127  * Drivers should NOT use these either.
 128  */
 129 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 130 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 131 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 132
 133 /*
 134  * Virtual <-> DMA view memory address translations
 135  * Again, these are *only* valid on the kernel direct mapped RAM
 136  * memory.  Use of these is *deprecated* (and that doesn't mean
 137  * use the __ prefixed forms instead.)  See dma-mapping.h.
 138  */
 139 static inline __deprecated unsigned long virt_to_bus(void *x)
 140 {
 141         return __virt_to_bus((unsigned long)x);
 142 }
 143
 144 static inline __deprecated void *bus_to_virt(unsigned long x)
 145 {
 146         return (void *)__bus_to_virt(x);
 147 }
 148
 149 /*
 150  * Conversion between a struct page and a physical address.
 151  *
 152  * Note: when converting an unknown physical address to a
 153  * struct page, the resulting pointer must be validated
 154  * using VALID_PAGE().  It must return an invalid struct page
 155  * for any physical address not corresponding to a system
 156  * RAM address.
 157  *
 158  *  page_to_pfn(page)   convert a struct page * to a PFN number
 159  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 160  *  pfn_valid(pfn)      indicates whether a PFN number is valid
 161  *
 162  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 163  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 164  */
 165 #ifndef CONFIG_DISCONTIGMEM
 166
 167 #define page_to_pfn(page)       (((page) - mem_map) + PHYS_PFN_OFFSET)
 168 #define pfn_to_page(pfn)        ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
 169 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
 170
 171 #define virt_to_page(kaddr)     (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
 172 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 173
 174 #define PHYS_TO_NID(addr)       (0)
 175
 176 #else /* CONFIG_DISCONTIGMEM */
 177
 178 /*
 179  * This is more complex.  We have a set of mem_map arrays spread
 180  * around in memory.
 181  */
 182 #include <linux/numa.h>
 183
 184 #define page_to_pfn(page)                                       \
 185         (( (page) - page_zone(page)->zone_mem_map)              \
 186           + page_zone(page)->zone_start_pfn)
 187
 188 #define pfn_to_page(pfn)                                        \
 189         (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
 190
 191 #define pfn_valid(pfn)                                          \
 192         ({                                                      \
 193                 unsigned int nid = PFN_TO_NID(pfn);             \
 194                 int valid = nid < MAX_NUMNODES;                 \
 195                 if (valid) {                                    \
 196                         pg_data_t *node = NODE_DATA(nid);       \
 197                         valid = (pfn - node->node_start_pfn) <  \
 198                                 node->node_spanned_pages;       \
 199                 }                                               \
 200                 valid;                                          \
 201         })
 202
 203 #define virt_to_page(kaddr)                                     \
 204         (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
 205
 206 #define virt_addr_valid(kaddr)  (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
 207
 208 /*
 209  * Common discontigmem stuff.
 210  *  PHYS_TO_NID is used by the ARM kernel/setup.c
 211  */
 212 #define PHYS_TO_NID(addr)       PFN_TO_NID((addr) >> PAGE_SHIFT)
 213
 214 #endif /* !CONFIG_DISCONTIGMEM */
 215
 216 /*
 217  * For BIO.  "will die".  Kill me when bio_to_phys() and bvec_to_phys() die.
 218  */
 219 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 220
 221 /*
 222  * Optional device DMA address remapping. Do _not_ use directly!
 223  * We should really eliminate virt_to_bus() here - it's deprecated.
 224  */
 225 #ifndef __arch_page_to_dma
 226 #define page_to_dma(dev, page)          ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
 227 #define dma_to_virt(dev, addr)          ((void *)__bus_to_virt(addr))
 228 #define virt_to_dma(dev, addr)          ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
 229 #else
 230 #define page_to_dma(dev, page)          (__arch_page_to_dma(dev, page))
 231 #define dma_to_virt(dev, addr)          (__arch_dma_to_virt(dev, addr))
 232 #define virt_to_dma(dev, addr)          (__arch_virt_to_dma(dev, addr))
 233 #endif
 234
 235 #endif
 236
 237 #endif