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 <linux/types.h>
  19 #include <linux/sizes.h>
  20
  21 #ifdef CONFIG_NEED_MACH_MEMORY_H
  22 #include <mach/memory.h>
  23 #endif
  24
  25 /*
  26  * Allow for constants defined here to be used from assembly code
  27  * by prepending the UL suffix only with actual C code compilation.
  28  */
  29 #define UL(x) _AC(x, UL)
  30
  31 #ifdef CONFIG_MMU
  32
  33 /*
  34  * PAGE_OFFSET - the virtual address of the start of the kernel image
  35  * TASK_SIZE - the maximum size of a user space task.
  36  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
  37  */
  38 #define PAGE_OFFSET             UL(CONFIG_PAGE_OFFSET)
  39 #define TASK_SIZE               (UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
  40 #define TASK_UNMAPPED_BASE      ALIGN(TASK_SIZE / 3, SZ_16M)
  41
  42 /*
  43  * The maximum size of a 26-bit user space task.
  44  */
  45 #define TASK_SIZE_26            (UL(1) << 26)
  46
  47 /*
  48  * The module space lives between the addresses given by TASK_SIZE
  49  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  50  */
  51 #ifndef CONFIG_THUMB2_KERNEL
  52 #define MODULES_VADDR           (PAGE_OFFSET - SZ_16M)
  53 #else
  54 /* smaller range for Thumb-2 symbols relocation (2^24)*/
  55 #define MODULES_VADDR           (PAGE_OFFSET - SZ_8M)
  56 #endif
  57
  58 #if TASK_SIZE > MODULES_VADDR
  59 #error Top of user space clashes with start of module space
  60 #endif
  61
  62 /*
  63  * The highmem pkmap virtual space shares the end of the module area.
  64  */
  65 #ifdef CONFIG_HIGHMEM
  66 #define MODULES_END             (PAGE_OFFSET - PMD_SIZE)
  67 #else
  68 #define MODULES_END             (PAGE_OFFSET)
  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)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
  77
  78 /*
  79  * Allow 16MB-aligned ioremap pages
  80  */
  81 #define IOREMAP_MAX_ORDER       24
  82
  83 #define CONSISTENT_END          (0xffe00000UL)
  84
  85 #else /* CONFIG_MMU */
  86
  87 /*
  88  * The limitation of user task size can grow up to the end of free ram region.
  89  * It is difficult to define and perhaps will never meet the original meaning
  90  * of this define that was meant to.
  91  * Fortunately, there is no reference for this in noMMU mode, for now.
  92  */
  93 #ifndef TASK_SIZE
  94 #define TASK_SIZE               (CONFIG_DRAM_SIZE)
  95 #endif
  96
  97 #ifndef TASK_UNMAPPED_BASE
  98 #define TASK_UNMAPPED_BASE      UL(0x00000000)
  99 #endif
 100
 101 #ifndef PHYS_OFFSET
 102 #define PHYS_OFFSET             UL(CONFIG_DRAM_BASE)
 103 #endif
 104
 105 #ifndef END_MEM
 106 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 107 #endif
 108
 109 #ifndef PAGE_OFFSET
 110 #define PAGE_OFFSET             (PHYS_OFFSET)
 111 #endif
 112
 113 /*
 114  * The module can be at any place in ram in nommu mode.
 115  */
 116 #define MODULES_END             (END_MEM)
 117 #define MODULES_VADDR           (PHYS_OFFSET)
 118
 119 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
 120
 121 #endif /* !CONFIG_MMU */
 122
 123 /*
 124  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 125  * locations
 126  */
 127 #ifdef CONFIG_HAVE_TCM
 128 #define ITCM_OFFSET     UL(0xfffe0000)
 129 #define DTCM_OFFSET     UL(0xfffe8000)
 130 #endif
 131
 132 /*
 133  * Convert a physical address to a Page Frame Number and back
 134  */
 135 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
 136 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
 137
 138 /*
 139  * Convert a page to/from a physical address
 140  */
 141 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 142 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 143
 144 #ifndef __ASSEMBLY__
 145
 146 /*
 147  * Physical vs virtual RAM address space conversion.  These are
 148  * private definitions which should NOT be used outside memory.h
 149  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 150  */
 151 #ifndef __virt_to_phys
 152 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 153
 154 /*
 155  * Constants used to force the right instruction encodings and shifts
 156  * so that all we need to do is modify the 8-bit constant field.
 157  */
 158 #define __PV_BITS_31_24 0x81000000
 159
 160 extern unsigned long __pv_phys_offset;
 161 #define PHYS_OFFSET __pv_phys_offset
 162
 163 #define __pv_stub(from,to,instr,type)                   \
 164         __asm__("@ __pv_stub\n"                         \
 165         "1:     " instr "       %0, %1, %2\n"           \
 166         "       .pushsection .pv_table,\"a\"\n"         \
 167         "       .long   1b\n"                           \
 168         "       .popsection\n"                          \
 169         : "=r" (to)                                     \
 170         : "r" (from), "I" (type))
 171
 172 static inline unsigned long __virt_to_phys(unsigned long x)
 173 {
 174         unsigned long t;
 175         __pv_stub(x, t, "add", __PV_BITS_31_24);
 176         return t;
 177 }
 178
 179 static inline unsigned long __phys_to_virt(unsigned long x)
 180 {
 181         unsigned long t;
 182         __pv_stub(x, t, "sub", __PV_BITS_31_24);
 183         return t;
 184 }
 185 #else
 186 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
 187 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
 188 #endif
 189 #endif
 190 #endif /* __ASSEMBLY__ */
 191
 192 #ifndef PHYS_OFFSET
 193 #ifdef PLAT_PHYS_OFFSET
 194 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 195 #else
 196 #define PHYS_OFFSET     UL(CONFIG_PHYS_OFFSET)
 197 #endif
 198 #endif
 199
 200 #ifndef __ASSEMBLY__
 201
 202 /*
 203  * PFNs are used to describe any physical page; this means
 204  * PFN 0 == physical address 0.
 205  *
 206  * This is the PFN of the first RAM page in the kernel
 207  * direct-mapped view.  We assume this is the first page
 208  * of RAM in the mem_map as well.
 209  */
 210 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 211
 212 /*
 213  * These are *only* valid on the kernel direct mapped RAM memory.
 214  * Note: Drivers should NOT use these.  They are the wrong
 215  * translation for translating DMA addresses.  Use the driver
 216  * DMA support - see dma-mapping.h.
 217  */
 218 static inline phys_addr_t virt_to_phys(const volatile void *x)
 219 {
 220         return __virt_to_phys((unsigned long)(x));
 221 }
 222
 223 static inline void *phys_to_virt(phys_addr_t x)
 224 {
 225         return (void *)(__phys_to_virt((unsigned long)(x)));
 226 }
 227
 228 /*
 229  * Drivers should NOT use these either.
 230  */
 231 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 232 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 233 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 234
 235 /*
 236  * Virtual <-> DMA view memory address translations
 237  * Again, these are *only* valid on the kernel direct mapped RAM
 238  * memory.  Use of these is *deprecated* (and that doesn't mean
 239  * use the __ prefixed forms instead.)  See dma-mapping.h.
 240  */
 241 #ifndef __virt_to_bus
 242 #define __virt_to_bus   __virt_to_phys
 243 #define __bus_to_virt   __phys_to_virt
 244 #define __pfn_to_bus(x) __pfn_to_phys(x)
 245 #define __bus_to_pfn(x) __phys_to_pfn(x)
 246 #endif
 247
 248 #ifdef CONFIG_VIRT_TO_BUS
 249 static inline __deprecated unsigned long virt_to_bus(void *x)
 250 {
 251         return __virt_to_bus((unsigned long)x);
 252 }
 253
 254 static inline __deprecated void *bus_to_virt(unsigned long x)
 255 {
 256         return (void *)__bus_to_virt(x);
 257 }
 258 #endif
 259
 260 /*
 261  * Conversion between a struct page and a physical address.
 262  *
 263  * Note: when converting an unknown physical address to a
 264  * struct page, the resulting pointer must be validated
 265  * using VALID_PAGE().  It must return an invalid struct page
 266  * for any physical address not corresponding to a system
 267  * RAM address.
 268  *
 269  *  page_to_pfn(page)   convert a struct page * to a PFN number
 270  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 271  *
 272  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 273  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 274  */
 275 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 276
 277 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 278 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 279
 280 #endif
 281
 282 #include <asm-generic/memory_model.h>
 283
 284 #endif