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#define VECTORS_BASE            UL(0xffff0000)
  87
  88#else /* CONFIG_MMU */
  89
  90#ifndef __ASSEMBLY__
  91extern unsigned long vectors_base;
  92#define VECTORS_BASE            vectors_base
  93#endif
  94
  95/*
  96 * The limitation of user task size can grow up to the end of free ram region.
  97 * It is difficult to define and perhaps will never meet the original meaning
  98 * of this define that was meant to.
  99 * Fortunately, there is no reference for this in noMMU mode, for now.
 100 */
 101#define TASK_SIZE               UL(0xffffffff)
 102
 103#ifndef TASK_UNMAPPED_BASE
 104#define TASK_UNMAPPED_BASE      UL(0x00000000)
 105#endif
 106
 107#ifndef END_MEM
 108#define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 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#ifdef CONFIG_XIP_KERNEL
 122#define KERNEL_START            _sdata
 123#else
 124#define KERNEL_START            _stext
 125#endif
 126#define KERNEL_END              _end
 127
 128/*
 129 * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 130 * locations
 131 */
 132#ifdef CONFIG_HAVE_TCM
 133#define ITCM_OFFSET     UL(0xfffe0000)
 134#define DTCM_OFFSET     UL(0xfffe8000)
 135#endif
 136
 137/*
 138 * Convert a page to/from a physical address
 139 */
 140#define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 141#define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 142
 143/*
 144 * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
 145 * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
 146 * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
 147 * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
 148 */
 149#define PLAT_PHYS_OFFSET        UL(CONFIG_PHYS_OFFSET)
 150
 151#ifdef CONFIG_XIP_KERNEL
 152/*
 153 * When referencing data in RAM from the XIP region in a relative manner
 154 * with the MMU off, we need the relative offset between the two physical
 155 * addresses.  The macro below achieves this, which is:
 156 *    __pa(v_data) - __xip_pa(v_text)
 157 */
 158#define PHYS_RELATIVE(v_data, v_text) \
 159        (((v_data) - PAGE_OFFSET + PLAT_PHYS_OFFSET) - \
 160         ((v_text) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) + \
 161          CONFIG_XIP_PHYS_ADDR))
 162#else
 163#define PHYS_RELATIVE(v_data, v_text) ((v_data) - (v_text))
 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 * PFNs are used to describe any physical page; this means
 174 * PFN 0 == physical address 0.
 175 */
 176
 177#if defined(CONFIG_ARM_PATCH_PHYS_VIRT)
 178
 179/*
 180 * Constants used to force the right instruction encodings and shifts
 181 * so that all we need to do is modify the 8-bit constant field.
 182 */
 183#define __PV_BITS_31_24 0x81000000
 184#define __PV_BITS_7_0   0x81
 185
 186extern unsigned long __pv_phys_pfn_offset;
 187extern u64 __pv_offset;
 188extern void fixup_pv_table(const void *, unsigned long);
 189extern const void *__pv_table_begin, *__pv_table_end;
 190
 191#define PHYS_OFFSET     ((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
 192#define PHYS_PFN_OFFSET (__pv_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
 223static inline phys_addr_t __virt_to_phys_nodebug(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
 236static 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
 255static inline phys_addr_t __virt_to_phys_nodebug(unsigned long x)
 256{
 257        return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 258}
 259
 260static inline unsigned long __phys_to_virt(phys_addr_t x)
 261{
 262        return x - PHYS_OFFSET + PAGE_OFFSET;
 263}
 264
 265#endif
 266
 267#define virt_to_pfn(kaddr) \
 268        ((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
 269         PHYS_PFN_OFFSET)
 270
 271#define __pa_symbol_nodebug(x)  __virt_to_phys_nodebug((x))
 272
 273#ifdef CONFIG_DEBUG_VIRTUAL
 274extern phys_addr_t __virt_to_phys(unsigned long x);
 275extern phys_addr_t __phys_addr_symbol(unsigned long x);
 276#else
 277#define __virt_to_phys(x)       __virt_to_phys_nodebug(x)
 278#define __phys_addr_symbol(x)   __pa_symbol_nodebug(x)
 279#endif
 280
 281/*
 282 * These are *only* valid on the kernel direct mapped RAM memory.
 283 * Note: Drivers should NOT use these.  They are the wrong
 284 * translation for translating DMA addresses.  Use the driver
 285 * DMA support - see dma-mapping.h.
 286 */
 287#define virt_to_phys virt_to_phys
 288static inline phys_addr_t virt_to_phys(const volatile void *x)
 289{
 290        return __virt_to_phys((unsigned long)(x));
 291}
 292
 293#define phys_to_virt phys_to_virt
 294static inline void *phys_to_virt(phys_addr_t x)
 295{
 296        return (void *)__phys_to_virt(x);
 297}
 298
 299/*
 300 * Drivers should NOT use these either.
 301 */
 302#define __pa(x)                 __virt_to_phys((unsigned long)(x))
 303#define __pa_symbol(x)          __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
 304#define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 305#define pfn_to_kaddr(pfn)       __va((phys_addr_t)(pfn) << PAGE_SHIFT)
 306
 307extern long long arch_phys_to_idmap_offset;
 308
 309/*
 310 * These are for systems that have a hardware interconnect supported alias
 311 * of physical memory for idmap purposes.  Most cases should leave these
 312 * untouched.  Note: this can only return addresses less than 4GiB.
 313 */
 314static inline bool arm_has_idmap_alias(void)
 315{
 316        return IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset != 0;
 317}
 318
 319#define IDMAP_INVALID_ADDR ((u32)~0)
 320
 321static inline unsigned long phys_to_idmap(phys_addr_t addr)
 322{
 323        if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset) {
 324                addr += arch_phys_to_idmap_offset;
 325                if (addr > (u32)~0)
 326                        addr = IDMAP_INVALID_ADDR;
 327        }
 328        return addr;
 329}
 330
 331static inline phys_addr_t idmap_to_phys(unsigned long idmap)
 332{
 333        phys_addr_t addr = idmap;
 334
 335        if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset)
 336                addr -= arch_phys_to_idmap_offset;
 337
 338        return addr;
 339}
 340
 341static inline unsigned long __virt_to_idmap(unsigned long x)
 342{
 343        return phys_to_idmap(__virt_to_phys(x));
 344}
 345
 346#define virt_to_idmap(x)        __virt_to_idmap((unsigned long)(x))
 347
 348/*
 349 * Virtual <-> DMA view memory address translations
 350 * Again, these are *only* valid on the kernel direct mapped RAM
 351 * memory.  Use of these is *deprecated* (and that doesn't mean
 352 * use the __ prefixed forms instead.)  See dma-mapping.h.
 353 */
 354#ifndef __virt_to_bus
 355#define __virt_to_bus   __virt_to_phys
 356#define __bus_to_virt   __phys_to_virt
 357#define __pfn_to_bus(x) __pfn_to_phys(x)
 358#define __bus_to_pfn(x) __phys_to_pfn(x)
 359#endif
 360
 361/*
 362 * Conversion between a struct page and a physical address.
 363 *
 364 *  page_to_pfn(page)   convert a struct page * to a PFN number
 365 *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 366 *
 367 *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 368 *  virt_addr_valid(k)  indicates whether a virtual address is valid
 369 */
 370#define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 371
 372#define virt_to_page(kaddr)     pfn_to_page(virt_to_pfn(kaddr))
 373#define virt_addr_valid(kaddr)  (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
 374                                        && pfn_valid(virt_to_pfn(kaddr)))
 375
 376#endif
 377
 378#include <asm-generic/memory_model.h>
 379
 380#endif
 381