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 #include <asm/sizes.h>
  29
  30 #ifndef TASK_SIZE
  31 /*
  32  * TASK_SIZE - the maximum size of a user space task.
  33  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
  34  */
  35 #define TASK_SIZE               UL(0xbf000000)
  36 #define TASK_UNMAPPED_BASE      UL(0x40000000)
  37 #endif
  38
  39 /*
  40  * The maximum size of a 26-bit user space task.
  41  */
  42 #define TASK_SIZE_26            UL(0x04000000)
  43
  44 /*
  45  * Page offset: 3GB
  46  */
  47 #ifndef PAGE_OFFSET
  48 #define PAGE_OFFSET             UL(0xc0000000)
  49 #endif
  50
  51 /*
  52  * Size of DMA-consistent memory region.  Must be multiple of 2M,
  53  * between 2MB and 14MB inclusive.
  54  */
  55 #ifndef CONSISTENT_DMA_SIZE
  56 #define CONSISTENT_DMA_SIZE SZ_2M
  57 #endif
  58
  59 /*
  60  * Physical vs virtual RAM address space conversion.  These are
  61  * private definitions which should NOT be used outside memory.h
  62  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  63  */
  64 #ifndef __virt_to_phys
  65 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
  66 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
  67 #endif
  68
  69 /*
  70  * Convert a physical address to a Page Frame Number and back
  71  */
  72 #define __phys_to_pfn(paddr)    ((paddr) >> PAGE_SHIFT)
  73 #define __pfn_to_phys(pfn)      ((pfn) << PAGE_SHIFT)
  74
  75 /*
  76  * The module space lives between the addresses given by TASK_SIZE
  77  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  78  */
  79 #define MODULE_END      (PAGE_OFFSET)
  80 #define MODULE_START    (MODULE_END - 16*1048576)
  81
  82 #if TASK_SIZE > MODULE_START
  83 #error Top of user space clashes with start of module space
  84 #endif
  85
  86 /*
  87  * The XIP kernel gets mapped at the bottom of the module vm area.
  88  * Since we use sections to map it, this macro replaces the physical address
  89  * with its virtual address while keeping offset from the base section.
  90  */
  91 #define XIP_VIRT_ADDR(physaddr)  (MODULE_START + ((physaddr) & 0x000fffff))
  92
  93 #ifndef __ASSEMBLY__
  94
  95 /*
  96  * The DMA mask corresponding to the maximum bus address allocatable
  97  * using GFP_DMA.  The default here places no restriction on DMA
  98  * allocations.  This must be the smallest DMA mask in the system,
  99  * so a successful GFP_DMA allocation will always satisfy this.
 100  */
 101 #ifndef ISA_DMA_THRESHOLD
 102 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
 103 #endif
 104
 105 #ifndef arch_adjust_zones
 106 #define arch_adjust_zones(node,size,holes) do { } while (0)
 107 #endif
 108
 109 /*
 110  * PFNs are used to describe any physical page; this means
 111  * PFN 0 == physical address 0.
 112  *
 113  * This is the PFN of the first RAM page in the kernel
 114  * direct-mapped view.  We assume this is the first page
 115  * of RAM in the mem_map as well.
 116  */
 117 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 118
 119 /*
 120  * These are *only* valid on the kernel direct mapped RAM memory.
 121  * Note: Drivers should NOT use these.  They are the wrong
 122  * translation for translating DMA addresses.  Use the driver
 123  * DMA support - see dma-mapping.h.
 124  */
 125 static inline unsigned long virt_to_phys(void *x)
 126 {
 127         return __virt_to_phys((unsigned long)(x));
 128 }
 129
 130 static inline void *phys_to_virt(unsigned long x)
 131 {
 132         return (void *)(__phys_to_virt((unsigned long)(x)));
 133 }
 134
 135 /*
 136  * Drivers should NOT use these either.
 137  */
 138 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 139 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 140 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 141
 142 /*
 143  * Virtual <-> DMA view memory address translations
 144  * Again, these are *only* valid on the kernel direct mapped RAM
 145  * memory.  Use of these is *deprecated* (and that doesn't mean
 146  * use the __ prefixed forms instead.)  See dma-mapping.h.
 147  */
 148 static inline __deprecated unsigned long virt_to_bus(void *x)
 149 {
 150         return __virt_to_bus((unsigned long)x);
 151 }
 152
 153 static inline __deprecated void *bus_to_virt(unsigned long x)
 154 {
 155         return (void *)__bus_to_virt(x);
 156 }
 157
 158 /*
 159  * Conversion between a struct page and a physical address.
 160  *
 161  * Note: when converting an unknown physical address to a
 162  * struct page, the resulting pointer must be validated
 163  * using VALID_PAGE().  It must return an invalid struct page
 164  * for any physical address not corresponding to a system
 165  * RAM address.
 166  *
 167  *  page_to_pfn(page)   convert a struct page * to a PFN number
 168  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 169  *  pfn_valid(pfn)      indicates whether a PFN number is valid
 170  *
 171  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 172  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 173  */
 174 #ifndef CONFIG_DISCONTIGMEM
 175
 176 #define page_to_pfn(page)       (((page) - mem_map) + PHYS_PFN_OFFSET)
 177 #define pfn_to_page(pfn)        ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
 178 #define pfn_valid(pfn)          ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
 179
 180 #define virt_to_page(kaddr)     (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
 181 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 182
 183 #define PHYS_TO_NID(addr)       (0)
 184
 185 #else /* CONFIG_DISCONTIGMEM */
 186
 187 /*
 188  * This is more complex.  We have a set of mem_map arrays spread
 189  * around in memory.
 190  */
 191 #include <linux/numa.h>
 192
 193 #define page_to_pfn(page)                                       \
 194         (( (page) - page_zone(page)->zone_mem_map)              \
 195           + page_zone(page)->zone_start_pfn)
 196
 197 #define pfn_to_page(pfn)                                        \
 198         (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
 199
 200 #define pfn_valid(pfn)                                          \
 201         ({                                                      \
 202                 unsigned int nid = PFN_TO_NID(pfn);             \
 203                 int valid = nid < MAX_NUMNODES;                 \
 204                 if (valid) {                                    \
 205                         pg_data_t *node = NODE_DATA(nid);       \
 206                         valid = (pfn - node->node_start_pfn) <  \
 207                                 node->node_spanned_pages;       \
 208                 }                                               \
 209                 valid;                                          \
 210         })
 211
 212 #define virt_to_page(kaddr)                                     \
 213         (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
 214
 215 #define virt_addr_valid(kaddr)  (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
 216
 217 /*
 218  * Common discontigmem stuff.
 219  *  PHYS_TO_NID is used by the ARM kernel/setup.c
 220  */
 221 #define PHYS_TO_NID(addr)       PFN_TO_NID((addr) >> PAGE_SHIFT)
 222
 223 #endif /* !CONFIG_DISCONTIGMEM */
 224
 225 /*
 226  * For BIO.  "will die".  Kill me when bio_to_phys() and bvec_to_phys() die.
 227  */
 228 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 229
 230 /*
 231  * Optional device DMA address remapping. Do _not_ use directly!
 232  * We should really eliminate virt_to_bus() here - it's deprecated.
 233  */
 234 #ifndef __arch_page_to_dma
 235 #define page_to_dma(dev, page)          ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
 236 #define dma_to_virt(dev, addr)          ((void *)__bus_to_virt(addr))
 237 #define virt_to_dma(dev, addr)          ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
 238 #else
 239 #define page_to_dma(dev, page)          (__arch_page_to_dma(dev, page))
 240 #define dma_to_virt(dev, addr)          (__arch_dma_to_virt(dev, addr))
 241 #define virt_to_dma(dev, addr)          (__arch_virt_to_dma(dev, addr))
 242 #endif
 243
 244 #endif
 245
 246 #endif