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 <mach/memory.h>
  20 #include <asm/sizes.h>
  21
  22 /*
  23  * Allow for constants defined here to be used from assembly code
  24  * by prepending the UL suffix only with actual C code compilation.
  25  */
  26 #define UL(x) _AC(x, UL)
  27
  28 #ifdef CONFIG_MMU
  29
  30 /*
  31  * PAGE_OFFSET - the virtual address of the start of the kernel image
  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 PAGE_OFFSET             UL(CONFIG_PAGE_OFFSET)
  36 #define TASK_SIZE               (UL(CONFIG_PAGE_OFFSET) - UL(0x01000000))
  37 #define TASK_UNMAPPED_BASE      (UL(CONFIG_PAGE_OFFSET) / 3)
  38
  39 /*
  40  * The maximum size of a 26-bit user space task.
  41  */
  42 #define TASK_SIZE_26            UL(0x04000000)
  43
  44 /*
  45  * The module space lives between the addresses given by TASK_SIZE
  46  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  47  */
  48 #ifndef CONFIG_THUMB2_KERNEL
  49 #define MODULES_VADDR           (PAGE_OFFSET - 16*1024*1024)
  50 #else
  51 /* smaller range for Thumb-2 symbols relocation (2^24)*/
  52 #define MODULES_VADDR           (PAGE_OFFSET - 8*1024*1024)
  53 #endif
  54
  55 #if TASK_SIZE > MODULES_VADDR
  56 #error Top of user space clashes with start of module space
  57 #endif
  58
  59 /*
  60  * The highmem pkmap virtual space shares the end of the module area.
  61  */
  62 #ifdef CONFIG_HIGHMEM
  63 #define MODULES_END             (PAGE_OFFSET - PMD_SIZE)
  64 #else
  65 #define MODULES_END             (PAGE_OFFSET)
  66 #endif
  67
  68 /*
  69  * The XIP kernel gets mapped at the bottom of the module vm area.
  70  * Since we use sections to map it, this macro replaces the physical address
  71  * with its virtual address while keeping offset from the base section.
  72  */
  73 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
  74
  75 /*
  76  * Allow 16MB-aligned ioremap pages
  77  */
  78 #define IOREMAP_MAX_ORDER       24
  79
  80 /*
  81  * Size of DMA-consistent memory region.  Must be multiple of 2M,
  82  * between 2MB and 14MB inclusive.
  83  */
  84 #ifndef CONSISTENT_DMA_SIZE
  85 #define CONSISTENT_DMA_SIZE     SZ_2M
  86 #endif
  87
  88 #define CONSISTENT_END          (0xffe00000UL)
  89 #define CONSISTENT_BASE         (CONSISTENT_END - CONSISTENT_DMA_SIZE)
  90
  91 #else /* CONFIG_MMU */
  92
  93 /*
  94  * The limitation of user task size can grow up to the end of free ram region.
  95  * It is difficult to define and perhaps will never meet the original meaning
  96  * of this define that was meant to.
  97  * Fortunately, there is no reference for this in noMMU mode, for now.
  98  */
  99 #ifndef TASK_SIZE
 100 #define TASK_SIZE               (CONFIG_DRAM_SIZE)
 101 #endif
 102
 103 #ifndef TASK_UNMAPPED_BASE
 104 #define TASK_UNMAPPED_BASE      UL(0x00000000)
 105 #endif
 106
 107 #ifndef PHYS_OFFSET
 108 #define PHYS_OFFSET             UL(CONFIG_DRAM_BASE)
 109 #endif
 110
 111 #ifndef END_MEM
 112 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 113 #endif
 114
 115 #ifndef PAGE_OFFSET
 116 #define PAGE_OFFSET             (PHYS_OFFSET)
 117 #endif
 118
 119 /*
 120  * The module can be at any place in ram in nommu mode.
 121  */
 122 #define MODULES_END             (END_MEM)
 123 #define MODULES_VADDR           (PHYS_OFFSET)
 124
 125 #endif /* !CONFIG_MMU */
 126
 127 /*
 128  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 129  * locations
 130  */
 131 #ifdef CONFIG_HAVE_TCM
 132 #define ITCM_OFFSET     UL(0xfffe0000)
 133 #define DTCM_OFFSET     UL(0xfffe8000)
 134 #endif
 135
 136 /*
 137  * Convert a physical address to a Page Frame Number and back
 138  */
 139 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
 140 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
 141
 142 /*
 143  * Convert a page to/from a physical address
 144  */
 145 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 146 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 147
 148 #ifndef __ASSEMBLY__
 149
 150 /*
 151  * Physical vs virtual RAM address space conversion.  These are
 152  * private definitions which should NOT be used outside memory.h
 153  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 154  */
 155 #ifndef __virt_to_phys
 156 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 157
 158 /*
 159  * Constants used to force the right instruction encodings and shifts
 160  * so that all we need to do is modify the 8-bit constant field.
 161  */
 162 #define __PV_BITS_31_24 0x81000000
 163 #define __PV_BITS_23_16 0x00810000
 164
 165 extern unsigned long __pv_phys_offset;
 166 #define PHYS_OFFSET __pv_phys_offset
 167
 168 #define __pv_stub(from,to,instr,type)                   \
 169         __asm__("@ __pv_stub\n"                         \
 170         "1:     " instr "       %0, %1, %2\n"           \
 171         "       .pushsection .pv_table,\"a\"\n"         \
 172         "       .long   1b\n"                           \
 173         "       .popsection\n"                          \
 174         : "=r" (to)                                     \
 175         : "r" (from), "I" (type))
 176
 177 static inline unsigned long __virt_to_phys(unsigned long x)
 178 {
 179         unsigned long t;
 180         __pv_stub(x, t, "add", __PV_BITS_31_24);
 181 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
 182         __pv_stub(t, t, "add", __PV_BITS_23_16);
 183 #endif
 184         return t;
 185 }
 186
 187 static inline unsigned long __phys_to_virt(unsigned long x)
 188 {
 189         unsigned long t;
 190         __pv_stub(x, t, "sub", __PV_BITS_31_24);
 191 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
 192         __pv_stub(t, t, "sub", __PV_BITS_23_16);
 193 #endif
 194         return t;
 195 }
 196 #else
 197 #define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
 198 #define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
 199 #endif
 200 #endif
 201
 202 #ifndef PHYS_OFFSET
 203 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 204 #endif
 205
 206 /*
 207  * PFNs are used to describe any physical page; this means
 208  * PFN 0 == physical address 0.
 209  *
 210  * This is the PFN of the first RAM page in the kernel
 211  * direct-mapped view.  We assume this is the first page
 212  * of RAM in the mem_map as well.
 213  */
 214 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 215
 216 /*
 217  * These are *only* valid on the kernel direct mapped RAM memory.
 218  * Note: Drivers should NOT use these.  They are the wrong
 219  * translation for translating DMA addresses.  Use the driver
 220  * DMA support - see dma-mapping.h.
 221  */
 222 static inline phys_addr_t virt_to_phys(const volatile void *x)
 223 {
 224         return __virt_to_phys((unsigned long)(x));
 225 }
 226
 227 static inline void *phys_to_virt(phys_addr_t x)
 228 {
 229         return (void *)(__phys_to_virt((unsigned long)(x)));
 230 }
 231
 232 /*
 233  * Drivers should NOT use these either.
 234  */
 235 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 236 #define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 237 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 238
 239 /*
 240  * Virtual <-> DMA view memory address translations
 241  * Again, these are *only* valid on the kernel direct mapped RAM
 242  * memory.  Use of these is *deprecated* (and that doesn't mean
 243  * use the __ prefixed forms instead.)  See dma-mapping.h.
 244  */
 245 #ifndef __virt_to_bus
 246 #define __virt_to_bus   __virt_to_phys
 247 #define __bus_to_virt   __phys_to_virt
 248 #define __pfn_to_bus(x) __pfn_to_phys(x)
 249 #define __bus_to_pfn(x) __phys_to_pfn(x)
 250 #endif
 251
 252 static inline __deprecated unsigned long virt_to_bus(void *x)
 253 {
 254         return __virt_to_bus((unsigned long)x);
 255 }
 256
 257 static inline __deprecated void *bus_to_virt(unsigned long x)
 258 {
 259         return (void *)__bus_to_virt(x);
 260 }
 261
 262 /*
 263  * Conversion between a struct page and a physical address.
 264  *
 265  * Note: when converting an unknown physical address to a
 266  * struct page, the resulting pointer must be validated
 267  * using VALID_PAGE().  It must return an invalid struct page
 268  * for any physical address not corresponding to a system
 269  * RAM address.
 270  *
 271  *  page_to_pfn(page)   convert a struct page * to a PFN number
 272  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 273  *
 274  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 275  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 276  */
 277 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 278
 279 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 280 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 281
 282 /*
 283  * Optional coherency support.  Currently used only by selected
 284  * Intel XSC3-based systems.
 285  */
 286 #ifndef arch_is_coherent
 287 #define arch_is_coherent()              0
 288 #endif
 289
 290 #endif
 291
 292 #include <asm-generic/memory_model.h>
 293
 294 #endif