linux/arch/arm/include/asm/memory.h
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   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#ifdef CONFIG_NEED_MACH_MEMORY_H
  22#include <mach/memory.h>
  23#endif
  24
  25/*
  26 * Allow for constants defined here to be used from assembly code
  27 * by prepending the UL suffix only with actual C code compilation.
  28 */
  29#define UL(x) _AC(x, UL)
  30
  31/* PAGE_OFFSET - the virtual address of the start of the kernel image */
  32#define PAGE_OFFSET             UL(CONFIG_PAGE_OFFSET)
  33
  34#ifdef CONFIG_MMU
  35
  36/*
  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 TASK_SIZE               (UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
  41#define TASK_UNMAPPED_BASE      ALIGN(TASK_SIZE / 3, SZ_16M)
  42
  43/*
  44 * The maximum size of a 26-bit user space task.
  45 */
  46#define TASK_SIZE_26            (UL(1) << 26)
  47
  48/*
  49 * The module space lives between the addresses given by TASK_SIZE
  50 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
  51 */
  52#ifndef CONFIG_THUMB2_KERNEL
  53#define MODULES_VADDR           (PAGE_OFFSET - SZ_16M)
  54#else
  55/* smaller range for Thumb-2 symbols relocation (2^24)*/
  56#define MODULES_VADDR           (PAGE_OFFSET - SZ_8M)
  57#endif
  58
  59#if TASK_SIZE > MODULES_VADDR
  60#error Top of user space clashes with start of module space
  61#endif
  62
  63/*
  64 * The highmem pkmap virtual space shares the end of the module area.
  65 */
  66#ifdef CONFIG_HIGHMEM
  67#define MODULES_END             (PAGE_OFFSET - PMD_SIZE)
  68#else
  69#define MODULES_END             (PAGE_OFFSET)
  70#endif
  71
  72/*
  73 * The XIP kernel gets mapped at the bottom of the module vm area.
  74 * Since we use sections to map it, this macro replaces the physical address
  75 * with its virtual address while keeping offset from the base section.
  76 */
  77#define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
  78
  79#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
  80/*
  81 * Allow 16MB-aligned ioremap pages
  82 */
  83#define IOREMAP_MAX_ORDER       24
  84#endif
  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 page to/from a physical address
 125 */
 126#define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 127#define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 128
 129/*
 130 * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
 131 * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
 132 * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
 133 * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
 134 */
 135#define PLAT_PHYS_OFFSET        UL(CONFIG_PHYS_OFFSET)
 136
 137#ifdef CONFIG_XIP_KERNEL
 138/*
 139 * When referencing data in RAM from the XIP region in a relative manner
 140 * with the MMU off, we need the relative offset between the two physical
 141 * addresses.  The macro below achieves this, which is:
 142 *    __pa(v_data) - __xip_pa(v_text)
 143 */
 144#define PHYS_RELATIVE(v_data, v_text) \
 145        (((v_data) - PAGE_OFFSET + PLAT_PHYS_OFFSET) - \
 146         ((v_text) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) + \
 147          CONFIG_XIP_PHYS_ADDR))
 148#else
 149#define PHYS_RELATIVE(v_data, v_text) ((v_data) - (v_text))
 150#endif
 151
 152#ifndef __ASSEMBLY__
 153
 154/*
 155 * Physical vs virtual RAM address space conversion.  These are
 156 * private definitions which should NOT be used outside memory.h
 157 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 158 *
 159 * PFNs are used to describe any physical page; this means
 160 * PFN 0 == physical address 0.
 161 */
 162
 163#if defined(CONFIG_ARM_PATCH_PHYS_VIRT)
 164
 165/*
 166 * Constants used to force the right instruction encodings and shifts
 167 * so that all we need to do is modify the 8-bit constant field.
 168 */
 169#define __PV_BITS_31_24 0x81000000
 170#define __PV_BITS_7_0   0x81
 171
 172extern unsigned long __pv_phys_pfn_offset;
 173extern u64 __pv_offset;
 174extern void fixup_pv_table(const void *, unsigned long);
 175extern const void *__pv_table_begin, *__pv_table_end;
 176
 177#define PHYS_OFFSET     ((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
 178#define PHYS_PFN_OFFSET (__pv_phys_pfn_offset)
 179
 180#define __pv_stub(from,to,instr,type)                   \
 181        __asm__("@ __pv_stub\n"                         \
 182        "1:     " instr "       %0, %1, %2\n"           \
 183        "       .pushsection .pv_table,\"a\"\n"         \
 184        "       .long   1b\n"                           \
 185        "       .popsection\n"                          \
 186        : "=r" (to)                                     \
 187        : "r" (from), "I" (type))
 188
 189#define __pv_stub_mov_hi(t)                             \
 190        __asm__ volatile("@ __pv_stub_mov\n"            \
 191        "1:     mov     %R0, %1\n"                      \
 192        "       .pushsection .pv_table,\"a\"\n"         \
 193        "       .long   1b\n"                           \
 194        "       .popsection\n"                          \
 195        : "=r" (t)                                      \
 196        : "I" (__PV_BITS_7_0))
 197
 198#define __pv_add_carry_stub(x, y)                       \
 199        __asm__ volatile("@ __pv_add_carry_stub\n"      \
 200        "1:     adds    %Q0, %1, %2\n"                  \
 201        "       adc     %R0, %R0, #0\n"                 \
 202        "       .pushsection .pv_table,\"a\"\n"         \
 203        "       .long   1b\n"                           \
 204        "       .popsection\n"                          \
 205        : "+r" (y)                                      \
 206        : "r" (x), "I" (__PV_BITS_31_24)                \
 207        : "cc")
 208
 209static inline phys_addr_t __virt_to_phys(unsigned long x)
 210{
 211        phys_addr_t t;
 212
 213        if (sizeof(phys_addr_t) == 4) {
 214                __pv_stub(x, t, "add", __PV_BITS_31_24);
 215        } else {
 216                __pv_stub_mov_hi(t);
 217                __pv_add_carry_stub(x, t);
 218        }
 219        return t;
 220}
 221
 222static inline unsigned long __phys_to_virt(phys_addr_t x)
 223{
 224        unsigned long t;
 225
 226        /*
 227         * 'unsigned long' cast discard upper word when
 228         * phys_addr_t is 64 bit, and makes sure that inline
 229         * assembler expression receives 32 bit argument
 230         * in place where 'r' 32 bit operand is expected.
 231         */
 232        __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
 233        return t;
 234}
 235
 236#else
 237
 238#define PHYS_OFFSET     PLAT_PHYS_OFFSET
 239#define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 240
 241static inline phys_addr_t __virt_to_phys(unsigned long x)
 242{
 243        return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 244}
 245
 246static inline unsigned long __phys_to_virt(phys_addr_t x)
 247{
 248        return x - PHYS_OFFSET + PAGE_OFFSET;
 249}
 250
 251#endif
 252
 253#define virt_to_pfn(kaddr) \
 254        ((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
 255         PHYS_PFN_OFFSET)
 256
 257/*
 258 * These are *only* valid on the kernel direct mapped RAM memory.
 259 * Note: Drivers should NOT use these.  They are the wrong
 260 * translation for translating DMA addresses.  Use the driver
 261 * DMA support - see dma-mapping.h.
 262 */
 263#define virt_to_phys virt_to_phys
 264static inline phys_addr_t virt_to_phys(const volatile void *x)
 265{
 266        return __virt_to_phys((unsigned long)(x));
 267}
 268
 269#define phys_to_virt phys_to_virt
 270static inline void *phys_to_virt(phys_addr_t x)
 271{
 272        return (void *)__phys_to_virt(x);
 273}
 274
 275/*
 276 * Drivers should NOT use these either.
 277 */
 278#define __pa(x)                 __virt_to_phys((unsigned long)(x))
 279#define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 280#define pfn_to_kaddr(pfn)       __va((phys_addr_t)(pfn) << PAGE_SHIFT)
 281
 282extern long long arch_phys_to_idmap_offset;
 283
 284/*
 285 * These are for systems that have a hardware interconnect supported alias
 286 * of physical memory for idmap purposes.  Most cases should leave these
 287 * untouched.  Note: this can only return addresses less than 4GiB.
 288 */
 289static inline bool arm_has_idmap_alias(void)
 290{
 291        return IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset != 0;
 292}
 293
 294#define IDMAP_INVALID_ADDR ((u32)~0)
 295
 296static inline unsigned long phys_to_idmap(phys_addr_t addr)
 297{
 298        if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset) {
 299                addr += arch_phys_to_idmap_offset;
 300                if (addr > (u32)~0)
 301                        addr = IDMAP_INVALID_ADDR;
 302        }
 303        return addr;
 304}
 305
 306static inline phys_addr_t idmap_to_phys(unsigned long idmap)
 307{
 308        phys_addr_t addr = idmap;
 309
 310        if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset)
 311                addr -= arch_phys_to_idmap_offset;
 312
 313        return addr;
 314}
 315
 316static inline unsigned long __virt_to_idmap(unsigned long x)
 317{
 318        return phys_to_idmap(__virt_to_phys(x));
 319}
 320
 321#define virt_to_idmap(x)        __virt_to_idmap((unsigned long)(x))
 322
 323/*
 324 * Virtual <-> DMA view memory address translations
 325 * Again, these are *only* valid on the kernel direct mapped RAM
 326 * memory.  Use of these is *deprecated* (and that doesn't mean
 327 * use the __ prefixed forms instead.)  See dma-mapping.h.
 328 */
 329#ifndef __virt_to_bus
 330#define __virt_to_bus   __virt_to_phys
 331#define __bus_to_virt   __phys_to_virt
 332#define __pfn_to_bus(x) __pfn_to_phys(x)
 333#define __bus_to_pfn(x) __phys_to_pfn(x)
 334#endif
 335
 336/*
 337 * Conversion between a struct page and a physical address.
 338 *
 339 *  page_to_pfn(page)   convert a struct page * to a PFN number
 340 *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 341 *
 342 *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 343 *  virt_addr_valid(k)  indicates whether a virtual address is valid
 344 */
 345#define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 346
 347#define virt_to_page(kaddr)     pfn_to_page(virt_to_pfn(kaddr))
 348#define virt_addr_valid(kaddr)  (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
 349                                        && pfn_valid(virt_to_pfn(kaddr)))
 350
 351#endif
 352
 353#include <asm-generic/memory_model.h>
 354
 355#endif
 356