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 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
 176extern unsigned long __pv_phys_offset;
 177#define PHYS_OFFSET __pv_phys_offset
 178
 179#define __pv_stub(from,to,instr,type)                   \
 180        __asm__("@ __pv_stub\n"                         \
 181        "1:     " instr "       %0, %1, %2\n"           \
 182        "       .pushsection .pv_table,\"a\"\n"         \
 183        "       .long   1b\n"                           \
 184        "       .popsection\n"                          \
 185        : "=r" (to)                                     \
 186        : "r" (from), "I" (type))
 187
 188static inline unsigned long __virt_to_phys(unsigned long x)
 189{
 190        unsigned long t;
 191        __pv_stub(x, t, "add", __PV_BITS_31_24);
 192        return t;
 193}
 194
 195static inline unsigned long __phys_to_virt(unsigned long x)
 196{
 197        unsigned long t;
 198        __pv_stub(x, t, "sub", __PV_BITS_31_24);
 199        return t;
 200}
 201#else
 202#define __virt_to_phys(x)       ((x) - PAGE_OFFSET + PHYS_OFFSET)
 203#define __phys_to_virt(x)       ((x) - PHYS_OFFSET + PAGE_OFFSET)
 204#endif
 205#endif
 206#endif /* __ASSEMBLY__ */
 207
 208#ifndef PHYS_OFFSET
 209#ifdef PLAT_PHYS_OFFSET
 210#define PHYS_OFFSET     PLAT_PHYS_OFFSET
 211#else
 212#define PHYS_OFFSET     UL(CONFIG_PHYS_OFFSET)
 213#endif
 214#endif
 215
 216#ifndef __ASSEMBLY__
 217
 218/*
 219 * PFNs are used to describe any physical page; this means
 220 * PFN 0 == physical address 0.
 221 *
 222 * This is the PFN of the first RAM page in the kernel
 223 * direct-mapped view.  We assume this is the first page
 224 * of RAM in the mem_map as well.
 225 */
 226#define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 227
 228/*
 229 * These are *only* valid on the kernel direct mapped RAM memory.
 230 * Note: Drivers should NOT use these.  They are the wrong
 231 * translation for translating DMA addresses.  Use the driver
 232 * DMA support - see dma-mapping.h.
 233 */
 234static inline phys_addr_t virt_to_phys(const volatile void *x)
 235{
 236        return __virt_to_phys((unsigned long)(x));
 237}
 238
 239static inline void *phys_to_virt(phys_addr_t x)
 240{
 241        return (void *)(__phys_to_virt((unsigned long)(x)));
 242}
 243
 244/*
 245 * Drivers should NOT use these either.
 246 */
 247#define __pa(x)                 __virt_to_phys((unsigned long)(x))
 248#define __va(x)                 ((void *)__phys_to_virt((unsigned long)(x)))
 249#define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 250
 251/*
 252 * Virtual <-> DMA view memory address translations
 253 * Again, these are *only* valid on the kernel direct mapped RAM
 254 * memory.  Use of these is *deprecated* (and that doesn't mean
 255 * use the __ prefixed forms instead.)  See dma-mapping.h.
 256 */
 257#ifndef __virt_to_bus
 258#define __virt_to_bus   __virt_to_phys
 259#define __bus_to_virt   __phys_to_virt
 260#define __pfn_to_bus(x) __pfn_to_phys(x)
 261#define __bus_to_pfn(x) __phys_to_pfn(x)
 262#endif
 263
 264#ifdef CONFIG_VIRT_TO_BUS
 265static inline __deprecated unsigned long virt_to_bus(void *x)
 266{
 267        return __virt_to_bus((unsigned long)x);
 268}
 269
 270static inline __deprecated void *bus_to_virt(unsigned long x)
 271{
 272        return (void *)__bus_to_virt(x);
 273}
 274#endif
 275
 276/*
 277 * Conversion between a struct page and a physical address.
 278 *
 279 *  page_to_pfn(page)   convert a struct page * to a PFN number
 280 *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 281 *
 282 *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 283 *  virt_addr_valid(k)  indicates whether a virtual address is valid
 284 */
 285#define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 286
 287#define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 288#define virt_addr_valid(kaddr)  ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
 289
 290#endif
 291
 292#include <asm-generic/memory_model.h>
 293
 294#endif
 295