arch/arm/include/asm/memory.h

   1 /*
   2  *  arch/arm/include/asm/memory.h
   3  *
   4  *  Copyright (C) 2000-2002 Russell King
   5  *  modification for nommu, Hyok S. Choi, 2004
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  *  Note: this file should not be included by non-asm/.h files
  12  */
  13 #ifndef __ASM_ARM_MEMORY_H
  14 #define __ASM_ARM_MEMORY_H
  15
  16 #include <linux/compiler.h>
  17 #include <linux/const.h>
  18 #include <mach/memory.h>
  19 #include <asm/sizes.h>
  20
  21 /*
  22  * Allow for constants defined here to be used from assembly code
  23  * by prepending the UL suffix only with actual C code compilation.
  24  */
  25 #define UL(x) _AC(x, UL)
  26
  27 #ifdef CONFIG_MMU
  28
  29 /*
  30  * PAGE_OFFSET - the virtual address of the start of the kernel image
  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 PAGE_OFFSET             UL(CONFIG_PAGE_OFFSET)
  35 #define TASK_SIZE               (UL(CONFIG_PAGE_OFFSET) - UL(0x01000000))
  36 #define TASK_UNMAPPED_BASE      (UL(CONFIG_PAGE_OFFSET) / 3)
  37
  38 /*
  39  * The maximum size of a 26-bit user space task.
  40  */
  41 #define TASK_SIZE_26            UL(0x04000000)
  42
  43 /*
  44  * The module space lives between the addresses given by TASK_SIZE
  45  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  46  */
  47 #ifndef CONFIG_THUMB2_KERNEL
  48 #define MODULES_VADDR           (PAGE_OFFSET - 16*1024*1024)
  49 #else
  50 /* smaller range for Thumb-2 symbols relocation (2^24)*/
  51 #define MODULES_VADDR           (PAGE_OFFSET - 8*1024*1024)
  52 #endif
  53
  54 #if TASK_SIZE > MODULES_VADDR
  55 #error Top of user space clashes with start of module space
  56 #endif
  57
  58 /*
  59  * The highmem pkmap virtual space shares the end of the module area.
  60  */
  61 #ifdef CONFIG_HIGHMEM
  62 #define MODULES_END             (PAGE_OFFSET - PMD_SIZE)
  63 #else
  64 #define MODULES_END             (PAGE_OFFSET)
  65 #endif
  66
  67 /*
  68  * The XIP kernel gets mapped at the bottom of the module vm area.
  69  * Since we use sections to map it, this macro replaces the physical address
  70  * with its virtual address while keeping offset from the base section.
  71  */
  72 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
  73
  74 /*
  75  * Allow 16MB-aligned ioremap pages
  76  */
  77 #define IOREMAP_MAX_ORDER       24
  78
  79 #else /* CONFIG_MMU */
  80
  81 /*
  82  * The limitation of user task size can grow up to the end of free ram region.
  83  * It is difficult to define and perhaps will never meet the original meaning
  84  * of this define that was meant to.
  85  * Fortunately, there is no reference for this in noMMU mode, for now.
  86  */
  87 #ifndef TASK_SIZE
  88 #define TASK_SIZE               (CONFIG_DRAM_SIZE)
  89 #endif
  90
  91 #ifndef TASK_UNMAPPED_BASE
  92 #define TASK_UNMAPPED_BASE      UL(0x00000000)
  93 #endif
  94
  95 #ifndef PHYS_OFFSET
  96 #define PHYS_OFFSET             (CONFIG_DRAM_BASE)
  97 #endif
  98
  99 #ifndef END_MEM
 100 #define END_MEM                 (CONFIG_DRAM_BASE + CONFIG_DRAM_SIZE)
 101 #endif
 102
 103 #ifndef PAGE_OFFSET
 104 #define PAGE_OFFSET             (PHYS_OFFSET)
 105 #endif
 106
 107 /*
 108  * The module can be at any place in ram in nommu mode.
 109  */
 110 #define MODULES_END             (END_MEM)
 111 #define MODULES_VADDR           (PHYS_OFFSET)
 112
 113 #endif /* !CONFIG_MMU */
 114
 115 /*
 116  * Size of DMA-consistent memory region.  Must be multiple of 2M,
 117  * between 2MB and 14MB inclusive.
 118  */
 119 #ifndef CONSISTENT_DMA_SIZE
 120 #define CONSISTENT_DMA_SIZE SZ_2M
 121 #endif
 122
 123 /*
 124  * Physical vs virtual RAM address space conversion.  These are
 125  * private definitions which should NOT be used outside memory.h
 126  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 127  */
 128 #ifndef __virt_to_phys
 129 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
 130 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
 131 #endif
 132
 133 /*
 134  * Convert a physical address to a Page Frame Number and back
 135  */
 136 #define __phys_to_pfn(paddr)    ((paddr) >> PAGE_SHIFT)
 137 #define __pfn_to_phys(pfn)      ((pfn) << PAGE_SHIFT)
 138
 139 /*
 140  * Convert a page to/from a physical address
 141  */
 142 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 143 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 144
 145 #ifndef __ASSEMBLY__
 146
 147 /*
 148  * The DMA mask corresponding to the maximum bus address allocatable
 149  * using GFP_DMA.  The default here places no restriction on DMA
 150  * allocations.  This must be the smallest DMA mask in the system,
 151  * so a successful GFP_DMA allocation will always satisfy this.
 152  */
 153 #ifndef ISA_DMA_THRESHOLD
 154 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
 155 #endif
 156
 157 #ifndef arch_adjust_zones
 158 #define arch_adjust_zones(node,size,holes) do { } while (0)
 159 #elif !defined(CONFIG_ZONE_DMA)
 160 #error "custom arch_adjust_zones() requires CONFIG_ZONE_DMA"
 161 #endif
 162
 163 /*
 164  * PFNs are used to describe any physical page; this means
 165  * PFN 0 == physical address 0.
 166  *
 167  * This is the PFN of the first RAM page in the kernel
 168  * direct-mapped view.  We assume this is the first page
 169  * of RAM in the mem_map as well.
 170  */
 171 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 172
 173 /*
 174  * These are *only* valid on the kernel direct mapped RAM memory.
 175  * Note: Drivers should NOT use these.  They are the wrong
 176  * translation for translating DMA addresses.  Use the driver
 177  * DMA support - see dma-mapping.h.
 178  */
 179 static inline unsigned long virt_to_phys(void *x)
 180 {
 181         return __virt_to_phys((unsigned long)(x));
 182 }
 183
 184 static inline void *phys_to_virt(unsigned long x)
 185 {
 186         return (void *)(__phys_to_virt((unsigned long)(x)));
 187 }
 188
 189 /*
 190  * Drivers should NOT use these either.
 191  */
 192 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 193 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 194 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 195
 196 /*
 197  * Virtual <-> DMA view memory address translations
 198  * Again, these are *only* valid on the kernel direct mapped RAM
 199  * memory.  Use of these is *deprecated* (and that doesn't mean
 200  * use the __ prefixed forms instead.)  See dma-mapping.h.
 201  */
 202 #ifndef __virt_to_bus
 203 #define __virt_to_bus   __virt_to_phys
 204 #define __bus_to_virt   __phys_to_virt
 205 #define __pfn_to_bus(x) __pfn_to_phys(x)
 206 #define __bus_to_pfn(x) __phys_to_pfn(x)
 207 #endif
 208
 209 static inline __deprecated unsigned long virt_to_bus(void *x)
 210 {
 211         return __virt_to_bus((unsigned long)x);
 212 }
 213
 214 static inline __deprecated void *bus_to_virt(unsigned long x)
 215 {
 216         return (void *)__bus_to_virt(x);
 217 }
 218
 219 /*
 220  * Conversion between a struct page and a physical address.
 221  *
 222  * Note: when converting an unknown physical address to a
 223  * struct page, the resulting pointer must be validated
 224  * using VALID_PAGE().  It must return an invalid struct page
 225  * for any physical address not corresponding to a system
 226  * RAM address.
 227  *
 228  *  page_to_pfn(page)   convert a struct page * to a PFN number
 229  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 230  *
 231  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 232  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 233  */
 234 #ifndef CONFIG_DISCONTIGMEM
 235
 236 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 237
 238 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 239 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 240
 241 #define PHYS_TO_NID(addr)       (0)
 242
 243 #else /* CONFIG_DISCONTIGMEM */
 244
 245 /*
 246  * This is more complex.  We have a set of mem_map arrays spread
 247  * around in memory.
 248  */
 249 #include <linux/numa.h>
 250
 251 #define arch_pfn_to_nid(pfn)    PFN_TO_NID(pfn)
 252 #define arch_local_page_offset(pfn, nid) LOCAL_MAP_NR((pfn) << PAGE_SHIFT)
 253
 254 #define virt_to_page(kaddr)                                     \
 255         (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
 256
 257 #define virt_addr_valid(kaddr)  (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
 258
 259 /*
 260  * Common discontigmem stuff.
 261  *  PHYS_TO_NID is used by the ARM kernel/setup.c
 262  */
 263 #define PHYS_TO_NID(addr)       PFN_TO_NID((addr) >> PAGE_SHIFT)
 264
 265 /*
 266  * Given a kaddr, ADDR_TO_MAPBASE finds the owning node of the memory
 267  * and returns the mem_map of that node.
 268  */
 269 #define ADDR_TO_MAPBASE(kaddr)  NODE_MEM_MAP(KVADDR_TO_NID(kaddr))
 270
 271 /*
 272  * Given a page frame number, find the owning node of the memory
 273  * and returns the mem_map of that node.
 274  */
 275 #define PFN_TO_MAPBASE(pfn)     NODE_MEM_MAP(PFN_TO_NID(pfn))
 276
 277 #ifdef NODE_MEM_SIZE_BITS
 278 #define NODE_MEM_SIZE_MASK      ((1 << NODE_MEM_SIZE_BITS) - 1)
 279
 280 /*
 281  * Given a kernel address, find the home node of the underlying memory.
 282  */
 283 #define KVADDR_TO_NID(addr) \
 284         (((unsigned long)(addr) - PAGE_OFFSET) >> NODE_MEM_SIZE_BITS)
 285
 286 /*
 287  * Given a page frame number, convert it to a node id.
 288  */
 289 #define PFN_TO_NID(pfn) \
 290         (((pfn) - PHYS_PFN_OFFSET) >> (NODE_MEM_SIZE_BITS - PAGE_SHIFT))
 291
 292 /*
 293  * Given a kaddr, LOCAL_MEM_MAP finds the owning node of the memory
 294  * and returns the index corresponding to the appropriate page in the
 295  * node's mem_map.
 296  */
 297 #define LOCAL_MAP_NR(addr) \
 298         (((unsigned long)(addr) & NODE_MEM_SIZE_MASK) >> PAGE_SHIFT)
 299
 300 #endif /* NODE_MEM_SIZE_BITS */
 301
 302 #endif /* !CONFIG_DISCONTIGMEM */
 303
 304 /*
 305  * Optional coherency support.  Currently used only by selected
 306  * Intel XSC3-based systems.
 307  */
 308 #ifndef arch_is_coherent
 309 #define arch_is_coherent()              0
 310 #endif
 311
 312 #endif
 313
 314 #include <asm-generic/memory_model.h>
 315
 316 #endif