LXR linux/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
 183extern u64 __pv_phys_offset;
 184extern u64 __pv_offset;
 185extern void fixup_pv_table(const void *, unsigned long);
 186extern 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
 219static 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
 232static 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
 250static inline phys_addr_t __virt_to_phys(unsigned long x)
 251{
 252        return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 253}
 254
 255static 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 */
 279static inline phys_addr_t virt_to_phys(const volatile void *x)
 280{
 281        return __virt_to_phys((unsigned long)(x));
 282}
 283
 284static 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
 296extern 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 */
 303static 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
 327static inline __deprecated unsigned long virt_to_bus(void *x)
 328{
 329        return __virt_to_bus((unsigned long)x);
 330}
 331
 332static 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
 358