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 #include <asm/cache.h>
  22
  23 #ifdef CONFIG_NEED_MACH_MEMORY_H
  24 #include <mach/memory.h>
  25 #endif
  26
  27 /*
  28  * Allow for constants defined here to be used from assembly code
  29  * by prepending the UL suffix only with actual C code compilation.
  30  */
  31 #define UL(x) _AC(x, UL)
  32
  33 #ifdef CONFIG_MMU
  34
  35 /*
  36  * PAGE_OFFSET - the virtual address of the start of the kernel image
  37  * TASK_SIZE - the maximum size of a user space task.
  38  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
  39  */
  40 #define PAGE_OFFSET             UL(CONFIG_PAGE_OFFSET)
  41 #define TASK_SIZE               (UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
  42 #define TASK_UNMAPPED_BASE      ALIGN(TASK_SIZE / 3, SZ_16M)
  43
  44 /*
  45  * The maximum size of a 26-bit user space task.
  46  */
  47 #define TASK_SIZE_26            (UL(1) << 26)
  48
  49 /*
  50  * The module space lives between the addresses given by TASK_SIZE
  51  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  52  */
  53 #ifndef CONFIG_THUMB2_KERNEL
  54 #define MODULES_VADDR           (PAGE_OFFSET - SZ_16M)
  55 #else
  56 /* smaller range for Thumb-2 symbols relocation (2^24)*/
  57 #define MODULES_VADDR           (PAGE_OFFSET - SZ_8M)
  58 #endif
  59
  60 #if TASK_SIZE > MODULES_VADDR
  61 #error Top of user space clashes with start of module space
  62 #endif
  63
  64 /*
  65  * The highmem pkmap virtual space shares the end of the module area.
  66  */
  67 #ifdef CONFIG_HIGHMEM
  68 #define MODULES_END             (PAGE_OFFSET - PMD_SIZE)
  69 #else
  70 #define MODULES_END             (PAGE_OFFSET)
  71 #endif
  72
  73 /*
  74  * The XIP kernel gets mapped at the bottom of the module vm area.
  75  * Since we use sections to map it, this macro replaces the physical address
  76  * with its virtual address while keeping offset from the base section.
  77  */
  78 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
  79
  80 /*
  81  * Allow 16MB-aligned ioremap pages
  82  */
  83 #define IOREMAP_MAX_ORDER       24
  84
  85 #define CONSISTENT_END          (0xffe00000UL)
  86
  87 #else /* CONFIG_MMU */
  88
  89 /*
  90  * The limitation of user task size can grow up to the end of free ram region.
  91  * It is difficult to define and perhaps will never meet the original meaning
  92  * of this define that was meant to.
  93  * Fortunately, there is no reference for this in noMMU mode, for now.
  94  */
  95 #ifndef TASK_SIZE
  96 #define TASK_SIZE               (CONFIG_DRAM_SIZE)
  97 #endif
  98
  99 #ifndef TASK_UNMAPPED_BASE
 100 #define TASK_UNMAPPED_BASE      UL(0x00000000)
 101 #endif
 102
 103 #ifndef PHYS_OFFSET
 104 #define PHYS_OFFSET             UL(CONFIG_DRAM_BASE)
 105 #endif
 106
 107 #ifndef END_MEM
 108 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 109 #endif
 110
 111 #ifndef PAGE_OFFSET
 112 #define PAGE_OFFSET             (PHYS_OFFSET)
 113 #endif
 114
 115 /*
 116  * The module can be at any place in ram in nommu mode.
 117  */
 118 #define MODULES_END             (END_MEM)
 119 #define MODULES_VADDR           (PHYS_OFFSET)
 120
 121 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
 122
 123 #endif /* !CONFIG_MMU */
 124
 125 /*
 126  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 127  * locations
 128  */
 129 #ifdef CONFIG_HAVE_TCM
 130 #define ITCM_OFFSET     UL(0xfffe0000)
 131 #define DTCM_OFFSET     UL(0xfffe8000)
 132 #endif
 133
 134 /*
 135  * Convert a physical address to a Page Frame Number and back
 136  */
 137 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
 138 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
 139
 140 /*
 141  * Convert a page to/from a physical address
 142  */
 143 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 144 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 145
 146 /*
 147  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
 148  * around in head.S and proc-*.S are shifted by this amount, in order to
 149  * leave spare high bits for systems with physical address extension.  This
 150  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
 151  * gives us about 38-bits or so.
 152  */
 153 #ifdef CONFIG_ARM_LPAE
 154 #define ARCH_PGD_SHIFT          L1_CACHE_SHIFT
 155 #else
 156 #define ARCH_PGD_SHIFT          0
 157 #endif
 158 #define ARCH_PGD_MASK           ((1 << ARCH_PGD_SHIFT) - 1)
 159
 160 #ifndef __ASSEMBLY__
 161
 162 /*
 163  * Physical vs virtual RAM address space conversion.  These are
 164  * private definitions which should NOT be used outside memory.h
 165  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 166  */
 167 #ifndef __virt_to_phys
 168 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 169
 170 /*
 171  * Constants used to force the right instruction encodings and shifts
 172  * so that all we need to do is modify the 8-bit constant field.
 173  */
 174 #define __PV_BITS_31_24 0x81000000
 175 #define __PV_BITS_7_0   0x81
 176
 177 extern u64 __pv_phys_offset;
 178 extern u64 __pv_offset;
 179 extern void fixup_pv_table(const void *, unsigned long);
 180 extern const void *__pv_table_begin, *__pv_table_end;
 181
 182 #define PHYS_OFFSET __pv_phys_offset
 183
 184 #define __pv_stub(from,to,instr,type)                   \
 185         __asm__("@ __pv_stub\n"                         \
 186         "1:     " instr "       %0, %1, %2\n"           \
 187         "       .pushsection .pv_table,\"a\"\n"         \
 188         "       .long   1b\n"                           \
 189         "       .popsection\n"                          \
 190         : "=r" (to)                                     \
 191         : "r" (from), "I" (type))
 192
 193 #define __pv_stub_mov_hi(t)                             \
 194         __asm__ volatile("@ __pv_stub_mov\n"            \
 195         "1:     mov     %R0, %1\n"                      \
 196         "       .pushsection .pv_table,\"a\"\n"         \
 197         "       .long   1b\n"                           \
 198         "       .popsection\n"                          \
 199         : "=r" (t)                                      \
 200         : "I" (__PV_BITS_7_0))
 201
 202 #define __pv_add_carry_stub(x, y)                       \
 203         __asm__ volatile("@ __pv_add_carry_stub\n"      \
 204         "1:     adds    %Q0, %1, %2\n"                  \
 205         "       adc     %R0, %R0, #0\n"                 \
 206         "       .pushsection .pv_table,\"a\"\n"         \
 207         "       .long   1b\n"                           \
 208         "       .popsection\n"                          \
 209         : "+r" (y)                                      \
 210         : "r" (x), "I" (__PV_BITS_31_24)                \
 211         : "cc")
 212
 213 static inline phys_addr_t __virt_to_phys(unsigned long x)
 214 {
 215         phys_addr_t t;
 216
 217         if (sizeof(phys_addr_t) == 4) {
 218                 __pv_stub(x, t, "add", __PV_BITS_31_24);
 219         } else {
 220                 __pv_stub_mov_hi(t);
 221                 __pv_add_carry_stub(x, t);
 222         }
 223         return t;
 224 }
 225
 226 static inline unsigned long __phys_to_virt(phys_addr_t x)
 227 {
 228         unsigned long t;
 229
 230         /*
 231          * 'unsigned long' cast discard upper word when
 232          * phys_addr_t is 64 bit, and makes sure that inline
 233          * assembler expression receives 32 bit argument
 234          * in place where 'r' 32 bit operand is expected.
 235          */
 236         __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
 237         return t;
 238 }
 239
 240 #else
 241
 242 static inline phys_addr_t __virt_to_phys(unsigned long x)
 243 {
 244         return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 245 }
 246
 247 static inline unsigned long __phys_to_virt(phys_addr_t x)
 248 {
 249         return x - PHYS_OFFSET + PAGE_OFFSET;
 250 }
 251
 252 #endif
 253 #endif
 254 #endif /* __ASSEMBLY__ */
 255
 256 #ifndef PHYS_OFFSET
 257 #ifdef PLAT_PHYS_OFFSET
 258 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 259 #else
 260 #define PHYS_OFFSET     UL(CONFIG_PHYS_OFFSET)
 261 #endif
 262 #endif
 263
 264 #ifndef __ASSEMBLY__
 265
 266 /*
 267  * PFNs are used to describe any physical page; this means
 268  * PFN 0 == physical address 0.
 269  *
 270  * This is the PFN of the first RAM page in the kernel
 271  * direct-mapped view.  We assume this is the first page
 272  * of RAM in the mem_map as well.
 273  */
 274 #define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 275
 276 /*
 277  * These are *only* valid on the kernel direct mapped RAM memory.
 278  * Note: Drivers should NOT use these.  They are the wrong
 279  * translation for translating DMA addresses.  Use the driver
 280  * DMA support - see dma-mapping.h.
 281  */
 282 static inline phys_addr_t virt_to_phys(const volatile void *x)
 283 {
 284         return __virt_to_phys((unsigned long)(x));
 285 }
 286
 287 static inline void *phys_to_virt(phys_addr_t x)
 288 {
 289         return (void *)__phys_to_virt(x);
 290 }
 291
 292 /*
 293  * Drivers should NOT use these either.
 294  */
 295 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 296 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 297 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 298
 299 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
 300
 301 /*
 302  * These are for systems that have a hardware interconnect supported alias of
 303  * physical memory for idmap purposes.  Most cases should leave these
 304  * untouched.
 305  */
 306 static inline phys_addr_t __virt_to_idmap(unsigned long x)
 307 {
 308         if (arch_virt_to_idmap)
 309                 return arch_virt_to_idmap(x);
 310         else
 311                 return __virt_to_phys(x);
 312 }
 313
 314 #define virt_to_idmap(x)        __virt_to_idmap((unsigned long)(x))
 315
 316 /*
 317  * Virtual <-> DMA view memory address translations
 318  * Again, these are *only* valid on the kernel direct mapped RAM
 319  * memory.  Use of these is *deprecated* (and that doesn't mean
 320  * use the __ prefixed forms instead.)  See dma-mapping.h.
 321  */
 322 #ifndef __virt_to_bus
 323 #define __virt_to_bus   __virt_to_phys
 324 #define __bus_to_virt   __phys_to_virt
 325 #define __pfn_to_bus(x) __pfn_to_phys(x)
 326 #define __bus_to_pfn(x) __phys_to_pfn(x)
 327 #endif
 328
 329 #ifdef CONFIG_VIRT_TO_BUS
 330 static inline __deprecated unsigned long virt_to_bus(void *x)
 331 {
 332         return __virt_to_bus((unsigned long)x);
 333 }
 334
 335 static inline __deprecated void *bus_to_virt(unsigned long x)
 336 {
 337         return (void *)__bus_to_virt(x);
 338 }
 339 #endif
 340
 341 /*
 342  * Conversion between a struct page and a physical address.
 343  *
 344  *  page_to_pfn(page)   convert a struct page * to a PFN number
 345  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 346  *
 347  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 348  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 349  */
 350 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 351
 352 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 353 #define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 354
 355 #endif
 356
 357 #include <asm-generic/memory_model.h>
 358
 359 #endif