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 /*
  80  * Size of DMA-consistent memory region.  Must be multiple of 2M,
  81  * between 2MB and 14MB inclusive.
  82  */
  83 #ifndef CONSISTENT_DMA_SIZE
  84 #define CONSISTENT_DMA_SIZE     SZ_2M
  85 #endif
  86
  87 #define CONSISTENT_END          (0xffe00000UL)
  88 #define CONSISTENT_BASE         (CONSISTENT_END - CONSISTENT_DMA_SIZE)
  89
  90 #else /* CONFIG_MMU */
  91
  92 /*
  93  * The limitation of user task size can grow up to the end of free ram region.
  94  * It is difficult to define and perhaps will never meet the original meaning
  95  * of this define that was meant to.
  96  * Fortunately, there is no reference for this in noMMU mode, for now.
  97  */
  98 #ifndef TASK_SIZE
  99 #define TASK_SIZE               (CONFIG_DRAM_SIZE)
 100 #endif
 101
 102 #ifndef TASK_UNMAPPED_BASE
 103 #define TASK_UNMAPPED_BASE      UL(0x00000000)
 104 #endif
 105
 106 #ifndef PHYS_OFFSET
 107 #define PHYS_OFFSET             UL(CONFIG_DRAM_BASE)
 108 #endif
 109
 110 #ifndef END_MEM
 111 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 112 #endif
 113
 114 #ifndef PAGE_OFFSET
 115 #define PAGE_OFFSET             (PHYS_OFFSET)
 116 #endif
 117
 118 /*
 119  * The module can be at any place in ram in nommu mode.
 120  */
 121 #define MODULES_END             (END_MEM)
 122 #define MODULES_VADDR           (PHYS_OFFSET)
 123
 124 #endif /* !CONFIG_MMU */
 125
 126 /*
 127  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 128  * locations
 129  */
 130 #ifdef CONFIG_HAVE_TCM
 131 #define ITCM_OFFSET     UL(0xfffe0000)
 132 #define DTCM_OFFSET     UL(0xfffe8000)
 133 #endif
 134
 135 /*
 136  * Convert a physical address to a Page Frame Number and back
 137  */
 138 #define __phys_to_pfn(paddr)    ((paddr) >> PAGE_SHIFT)
 139 #define __pfn_to_phys(pfn)      ((pfn) << PAGE_SHIFT)
 140
 141 /*
 142  * Convert a page to/from a physical address
 143  */
 144 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 145 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 146
 147 #ifndef __ASSEMBLY__
 148
 149 /*
 150  * Physical vs virtual RAM address space conversion.  These are
 151  * private definitions which should NOT be used outside memory.h
 152  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 153  */
 154 #ifndef __virt_to_phys
 155 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 156
 157 /*
 158  * Constants used to force the right instruction encodings and shifts
 159  * so that all we need to do is modify the 8-bit constant field.
 160  */
 161 #define __PV_BITS_31_24 0x81000000
 162 #define __PV_BITS_23_16 0x00810000
 163
 164 extern unsigned long __pv_phys_offset;
 165 #define PHYS_OFFSET __pv_phys_offset
 166
 167 #define __pv_stub(from,to,instr,type)                   \
 168         __asm__("@ __pv_stub\n"                         \
 169         "1:     " instr "       %0, %1, %2\n"           \
 170         "       .pushsection .pv_table,\"a\"\n"         \
 171         "       .long   1b\n"                           \
 172         "       .popsection\n"                          \
 173         : "=r" (to)                                     \
 174         : "r" (from), "I" (type))
 175
 176 static inline unsigned long __virt_to_phys(unsigned long x)
 177 {
 178         unsigned long t;
 179         __pv_stub(x, t, "add", __PV_BITS_31_24);
 180 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
 181         __pv_stub(t, t, "add", __PV_BITS_23_16);
 182 #endif
 183         return t;
 184 }
 185
 186 static inline unsigned long __phys_to_virt(unsigned long x)
 187 {
 188         unsigned long t;
 189         __pv_stub(x, t, "sub", __PV_BITS_31_24);
 190 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
 191         __pv_stub(t, t, "sub", __PV_BITS_23_16);
 192 #endif
 193         return t;
 194 }
 195 #else
 196 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
 197 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
 198 #endif
 199 #endif
 200
 201 #ifndef PHYS_OFFSET
 202 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 203 #endif
 204
 205 /*
 206  * The DMA mask corresponding to the maximum bus address allocatable
 207  * using GFP_DMA.  The default here places no restriction on DMA
 208  * allocations.  This must be the smallest DMA mask in the system,
 209  * so a successful GFP_DMA allocation will always satisfy this.
 210  */
 211 #ifndef ISA_DMA_THRESHOLD
 212 #define ISA_DMA_THRESHOLD       (0xffffffffULL)
 213 #endif
 214
 215 #ifndef arch_adjust_zones
 216 #define arch_adjust_zones(size,holes) do { } while (0)
 217 #elif !defined(CONFIG_ZONE_DMA)
 218 #error "custom arch_adjust_zones() requires CONFIG_ZONE_DMA"
 219 #endif
 220
 221 /*
 222  * PFNs are used to describe any physical page; this means
 223  * PFN 0 == physical address 0.
 224  *
 225  * This is the PFN of the first RAM page in the kernel
 226  * direct-mapped view.  We assume this is the first page
 227  * of RAM in the mem_map as well.
 228  */
 229 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 230
 231 /*
 232  * These are *only* valid on the kernel direct mapped RAM memory.
 233  * Note: Drivers should NOT use these.  They are the wrong
 234  * translation for translating DMA addresses.  Use the driver
 235  * DMA support - see dma-mapping.h.
 236  */
 237 static inline unsigned long virt_to_phys(const volatile void *x)
 238 {
 239         return __virt_to_phys((unsigned long)(x));
 240 }
 241
 242 static inline void *phys_to_virt(unsigned long x)
 243 {
 244         return (void *)(__phys_to_virt((unsigned long)(x)));
 245 }
 246
 247 /*
 248  * Drivers should NOT use these either.
 249  */
 250 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 251 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 252 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 253
 254 /*
 255  * Virtual <-> DMA view memory address translations
 256  * Again, these are *only* valid on the kernel direct mapped RAM
 257  * memory.  Use of these is *deprecated* (and that doesn't mean
 258  * use the __ prefixed forms instead.)  See dma-mapping.h.
 259  */
 260 #ifndef __virt_to_bus
 261 #define __virt_to_bus   __virt_to_phys
 262 #define __bus_to_virt   __phys_to_virt
 263 #define __pfn_to_bus(x) __pfn_to_phys(x)
 264 #define __bus_to_pfn(x) __phys_to_pfn(x)
 265 #endif
 266
 267 static inline __deprecated unsigned long virt_to_bus(void *x)
 268 {
 269         return __virt_to_bus((unsigned long)x);
 270 }
 271
 272 static inline __deprecated void *bus_to_virt(unsigned long x)
 273 {
 274         return (void *)__bus_to_virt(x);
 275 }
 276
 277 /*
 278  * Conversion between a struct page and a physical address.
 279  *
 280  * Note: when converting an unknown physical address to a
 281  * struct page, the resulting pointer must be validated
 282  * using VALID_PAGE().  It must return an invalid struct page
 283  * for any physical address not corresponding to a system
 284  * RAM address.
 285  *
 286  *  page_to_pfn(page)   convert a struct page * to a PFN number
 287  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 288  *
 289  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 290  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 291  */
 292 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 293
 294 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 295 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 296
 297 /*
 298  * Optional coherency support.  Currently used only by selected
 299  * Intel XSC3-based systems.
 300  */
 301 #ifndef arch_is_coherent
 302 #define arch_is_coherent()              0
 303 #endif
 304
 305 #endif
 306
 307 #include <asm-generic/memory_model.h>
 308
 309 #endif