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