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 END_MEM
 104 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 105 #endif
 106
 107 #ifndef PAGE_OFFSET
 108 #define PAGE_OFFSET             PLAT_PHYS_OFFSET
 109 #endif
 110
 111 /*
 112  * The module can be at any place in ram in nommu mode.
 113  */
 114 #define MODULES_END             (END_MEM)
 115 #define MODULES_VADDR           PAGE_OFFSET
 116
 117 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
 118
 119 #endif /* !CONFIG_MMU */
 120
 121 /*
 122  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 123  * locations
 124  */
 125 #ifdef CONFIG_HAVE_TCM
 126 #define ITCM_OFFSET     UL(0xfffe0000)
 127 #define DTCM_OFFSET     UL(0xfffe8000)
 128 #endif
 129
 130 /*
 131  * Convert a physical address to a Page Frame Number and back
 132  */
 133 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
 134 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
 135
 136 /*
 137  * Convert a page to/from a physical address
 138  */
 139 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 140 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 141
 142 /*
 143  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
 144  * around in head.S and proc-*.S are shifted by this amount, in order to
 145  * leave spare high bits for systems with physical address extension.  This
 146  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
 147  * gives us about 38-bits or so.
 148  */
 149 #ifdef CONFIG_ARM_LPAE
 150 #define ARCH_PGD_SHIFT          L1_CACHE_SHIFT
 151 #else
 152 #define ARCH_PGD_SHIFT          0
 153 #endif
 154 #define ARCH_PGD_MASK           ((1 << ARCH_PGD_SHIFT) - 1)
 155
 156 /*
 157  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
 158  * memory.  This is used for XIP and NoMMU kernels, or by kernels which
 159  * have their own mach/memory.h.  Assembly code must always use
 160  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
 161  */
 162 #ifndef PLAT_PHYS_OFFSET
 163 #define PLAT_PHYS_OFFSET        UL(CONFIG_PHYS_OFFSET)
 164 #endif
 165
 166 #ifndef __ASSEMBLY__
 167
 168 /*
 169  * Physical vs virtual RAM address space conversion.  These are
 170  * private definitions which should NOT be used outside memory.h
 171  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 172  */
 173 #ifndef __virt_to_phys
 174 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 175
 176 /*
 177  * Constants used to force the right instruction encodings and shifts
 178  * so that all we need to do is modify the 8-bit constant field.
 179  */
 180 #define __PV_BITS_31_24 0x81000000
 181 #define __PV_BITS_7_0   0x81
 182
 183 extern u64 __pv_phys_offset;
 184 extern u64 __pv_offset;
 185 extern void fixup_pv_table(const void *, unsigned long);
 186 extern const void *__pv_table_begin, *__pv_table_end;
 187
 188 #define PHYS_OFFSET __pv_phys_offset
 189
 190 #define __pv_stub(from,to,instr,type)                   \
 191         __asm__("@ __pv_stub\n"                         \
 192         "1:     " instr "       %0, %1, %2\n"           \
 193         "       .pushsection .pv_table,\"a\"\n"         \
 194         "       .long   1b\n"                           \
 195         "       .popsection\n"                          \
 196         : "=r" (to)                                     \
 197         : "r" (from), "I" (type))
 198
 199 #define __pv_stub_mov_hi(t)                             \
 200         __asm__ volatile("@ __pv_stub_mov\n"            \
 201         "1:     mov     %R0, %1\n"                      \
 202         "       .pushsection .pv_table,\"a\"\n"         \
 203         "       .long   1b\n"                           \
 204         "       .popsection\n"                          \
 205         : "=r" (t)                                      \
 206         : "I" (__PV_BITS_7_0))
 207
 208 #define __pv_add_carry_stub(x, y)                       \
 209         __asm__ volatile("@ __pv_add_carry_stub\n"      \
 210         "1:     adds    %Q0, %1, %2\n"                  \
 211         "       adc     %R0, %R0, #0\n"                 \
 212         "       .pushsection .pv_table,\"a\"\n"         \
 213         "       .long   1b\n"                           \
 214         "       .popsection\n"                          \
 215         : "+r" (y)                                      \
 216         : "r" (x), "I" (__PV_BITS_31_24)                \
 217         : "cc")
 218
 219 static inline phys_addr_t __virt_to_phys(unsigned long x)
 220 {
 221         phys_addr_t t;
 222
 223         if (sizeof(phys_addr_t) == 4) {
 224                 __pv_stub(x, t, "add", __PV_BITS_31_24);
 225         } else {
 226                 __pv_stub_mov_hi(t);
 227                 __pv_add_carry_stub(x, t);
 228         }
 229         return t;
 230 }
 231
 232 static inline unsigned long __phys_to_virt(phys_addr_t x)
 233 {
 234         unsigned long t;
 235
 236         /*
 237          * 'unsigned long' cast discard upper word when
 238          * phys_addr_t is 64 bit, and makes sure that inline
 239          * assembler expression receives 32 bit argument
 240          * in place where 'r' 32 bit operand is expected.
 241          */
 242         __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
 243         return t;
 244 }
 245
 246 #else
 247
 248 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 249
 250 static inline phys_addr_t __virt_to_phys(unsigned long x)
 251 {
 252         return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 253 }
 254
 255 static inline unsigned long __phys_to_virt(phys_addr_t x)
 256 {
 257         return x - PHYS_OFFSET + PAGE_OFFSET;
 258 }
 259
 260 #endif
 261 #endif
 262
 263 /*
 264  * PFNs are used to describe any physical page; this means
 265  * PFN 0 == physical address 0.
 266  *
 267  * This is the PFN of the first RAM page in the kernel
 268  * direct-mapped view.  We assume this is the first page
 269  * of RAM in the mem_map as well.
 270  */
 271 #define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 272
 273 /*
 274  * These are *only* valid on the kernel direct mapped RAM memory.
 275  * Note: Drivers should NOT use these.  They are the wrong
 276  * translation for translating DMA addresses.  Use the driver
 277  * DMA support - see dma-mapping.h.
 278  */
 279 static inline phys_addr_t virt_to_phys(const volatile void *x)
 280 {
 281         return __virt_to_phys((unsigned long)(x));
 282 }
 283
 284 static inline void *phys_to_virt(phys_addr_t x)
 285 {
 286         return (void *)__phys_to_virt(x);
 287 }
 288
 289 /*
 290  * Drivers should NOT use these either.
 291  */
 292 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 293 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 294 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 295
 296 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
 297
 298 /*
 299  * These are for systems that have a hardware interconnect supported alias of
 300  * physical memory for idmap purposes.  Most cases should leave these
 301  * untouched.
 302  */
 303 static inline phys_addr_t __virt_to_idmap(unsigned long x)
 304 {
 305         if (arch_virt_to_idmap)
 306                 return arch_virt_to_idmap(x);
 307         else
 308                 return __virt_to_phys(x);
 309 }
 310
 311 #define virt_to_idmap(x)        __virt_to_idmap((unsigned long)(x))
 312
 313 /*
 314  * Virtual <-> DMA view memory address translations
 315  * Again, these are *only* valid on the kernel direct mapped RAM
 316  * memory.  Use of these is *deprecated* (and that doesn't mean
 317  * use the __ prefixed forms instead.)  See dma-mapping.h.
 318  */
 319 #ifndef __virt_to_bus
 320 #define __virt_to_bus   __virt_to_phys
 321 #define __bus_to_virt   __phys_to_virt
 322 #define __pfn_to_bus(x) __pfn_to_phys(x)
 323 #define __bus_to_pfn(x) __phys_to_pfn(x)
 324 #endif
 325
 326 #ifdef CONFIG_VIRT_TO_BUS
 327 static inline __deprecated unsigned long virt_to_bus(void *x)
 328 {
 329         return __virt_to_bus((unsigned long)x);
 330 }
 331
 332 static inline __deprecated void *bus_to_virt(unsigned long x)
 333 {
 334         return (void *)__bus_to_virt(x);
 335 }
 336 #endif
 337
 338 /*
 339  * Conversion between a struct page and a physical address.
 340  *
 341  *  page_to_pfn(page)   convert a struct page * to a PFN number
 342  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 343  *
 344  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 345  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 346  */
 347 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 348
 349 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 350 #define virt_addr_valid(kaddr)  (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
 351                                         && pfn_valid(__pa(kaddr) >> PAGE_SHIFT) )
 352
 353 #endif
 354
 355 #include <asm-generic/memory_model.h>
 356
 357 #endif