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 #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 /*
  80  * Allow 16MB-aligned ioremap pages
  81  */
  82 #define IOREMAP_MAX_ORDER       24
  83
  84 #else /* CONFIG_MMU */
  85
  86 /*
  87  * The limitation of user task size can grow up to the end of free ram region.
  88  * It is difficult to define and perhaps will never meet the original meaning
  89  * of this define that was meant to.
  90  * Fortunately, there is no reference for this in noMMU mode, for now.
  91  */
  92 #define TASK_SIZE               UL(0xffffffff)
  93
  94 #ifndef TASK_UNMAPPED_BASE
  95 #define TASK_UNMAPPED_BASE      UL(0x00000000)
  96 #endif
  97
  98 #ifndef END_MEM
  99 #define END_MEM                 (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 100 #endif
 101
 102 /*
 103  * The module can be at any place in ram in nommu mode.
 104  */
 105 #define MODULES_END             (END_MEM)
 106 #define MODULES_VADDR           PAGE_OFFSET
 107
 108 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
 109
 110 #endif /* !CONFIG_MMU */
 111
 112 /*
 113  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 114  * locations
 115  */
 116 #ifdef CONFIG_HAVE_TCM
 117 #define ITCM_OFFSET     UL(0xfffe0000)
 118 #define DTCM_OFFSET     UL(0xfffe8000)
 119 #endif
 120
 121 /*
 122  * Convert a physical address to a Page Frame Number and back
 123  */
 124 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
 125 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
 126
 127 /*
 128  * Convert a page to/from a physical address
 129  */
 130 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 131 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 132
 133 /*
 134  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
 135  * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
 136  * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
 137  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
 138  */
 139 #define PLAT_PHYS_OFFSET        UL(CONFIG_PHYS_OFFSET)
 140
 141 #ifndef __ASSEMBLY__
 142
 143 /*
 144  * Physical vs virtual RAM address space conversion.  These are
 145  * private definitions which should NOT be used outside memory.h
 146  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 147  *
 148  * PFNs are used to describe any physical page; this means
 149  * PFN 0 == physical address 0.
 150  */
 151 #if defined(__virt_to_phys)
 152 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 153 #define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 154
 155 #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
 156
 157 #elif defined(CONFIG_ARM_PATCH_PHYS_VIRT)
 158
 159 /*
 160  * Constants used to force the right instruction encodings and shifts
 161  * so that all we need to do is modify the 8-bit constant field.
 162  */
 163 #define __PV_BITS_31_24 0x81000000
 164 #define __PV_BITS_7_0   0x81
 165
 166 extern unsigned long __pv_phys_pfn_offset;
 167 extern u64 __pv_offset;
 168 extern void fixup_pv_table(const void *, unsigned long);
 169 extern const void *__pv_table_begin, *__pv_table_end;
 170
 171 #define PHYS_OFFSET     ((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
 172 #define PHYS_PFN_OFFSET (__pv_phys_pfn_offset)
 173
 174 #define virt_to_pfn(kaddr) \
 175         ((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
 176          PHYS_PFN_OFFSET)
 177
 178 #define __pv_stub(from,to,instr,type)                   \
 179         __asm__("@ __pv_stub\n"                         \
 180         "1:     " instr "       %0, %1, %2\n"           \
 181         "       .pushsection .pv_table,\"a\"\n"         \
 182         "       .long   1b\n"                           \
 183         "       .popsection\n"                          \
 184         : "=r" (to)                                     \
 185         : "r" (from), "I" (type))
 186
 187 #define __pv_stub_mov_hi(t)                             \
 188         __asm__ volatile("@ __pv_stub_mov\n"            \
 189         "1:     mov     %R0, %1\n"                      \
 190         "       .pushsection .pv_table,\"a\"\n"         \
 191         "       .long   1b\n"                           \
 192         "       .popsection\n"                          \
 193         : "=r" (t)                                      \
 194         : "I" (__PV_BITS_7_0))
 195
 196 #define __pv_add_carry_stub(x, y)                       \
 197         __asm__ volatile("@ __pv_add_carry_stub\n"      \
 198         "1:     adds    %Q0, %1, %2\n"                  \
 199         "       adc     %R0, %R0, #0\n"                 \
 200         "       .pushsection .pv_table,\"a\"\n"         \
 201         "       .long   1b\n"                           \
 202         "       .popsection\n"                          \
 203         : "+r" (y)                                      \
 204         : "r" (x), "I" (__PV_BITS_31_24)                \
 205         : "cc")
 206
 207 static inline phys_addr_t __virt_to_phys(unsigned long x)
 208 {
 209         phys_addr_t t;
 210
 211         if (sizeof(phys_addr_t) == 4) {
 212                 __pv_stub(x, t, "add", __PV_BITS_31_24);
 213         } else {
 214                 __pv_stub_mov_hi(t);
 215                 __pv_add_carry_stub(x, t);
 216         }
 217         return t;
 218 }
 219
 220 static inline unsigned long __phys_to_virt(phys_addr_t x)
 221 {
 222         unsigned long t;
 223
 224         /*
 225          * 'unsigned long' cast discard upper word when
 226          * phys_addr_t is 64 bit, and makes sure that inline
 227          * assembler expression receives 32 bit argument
 228          * in place where 'r' 32 bit operand is expected.
 229          */
 230         __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
 231         return t;
 232 }
 233
 234 #else
 235
 236 #define PHYS_OFFSET     PLAT_PHYS_OFFSET
 237 #define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
 238
 239 static inline phys_addr_t __virt_to_phys(unsigned long x)
 240 {
 241         return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 242 }
 243
 244 static inline unsigned long __phys_to_virt(phys_addr_t x)
 245 {
 246         return x - PHYS_OFFSET + PAGE_OFFSET;
 247 }
 248
 249 #define virt_to_pfn(kaddr) \
 250         ((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
 251          PHYS_PFN_OFFSET)
 252
 253 #endif
 254
 255 /*
 256  * These are *only* valid on the kernel direct mapped RAM memory.
 257  * Note: Drivers should NOT use these.  They are the wrong
 258  * translation for translating DMA addresses.  Use the driver
 259  * DMA support - see dma-mapping.h.
 260  */
 261 #define virt_to_phys virt_to_phys
 262 static inline phys_addr_t virt_to_phys(const volatile void *x)
 263 {
 264         return __virt_to_phys((unsigned long)(x));
 265 }
 266
 267 #define phys_to_virt phys_to_virt
 268 static inline void *phys_to_virt(phys_addr_t x)
 269 {
 270         return (void *)__phys_to_virt(x);
 271 }
 272
 273 /*
 274  * Drivers should NOT use these either.
 275  */
 276 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 277 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 278 #define pfn_to_kaddr(pfn)       __va((phys_addr_t)(pfn) << PAGE_SHIFT)
 279
 280 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
 281
 282 /*
 283  * These are for systems that have a hardware interconnect supported alias of
 284  * physical memory for idmap purposes.  Most cases should leave these
 285  * untouched.
 286  */
 287 static inline phys_addr_t __virt_to_idmap(unsigned long x)
 288 {
 289         if (IS_ENABLED(CONFIG_MMU) && arch_virt_to_idmap)
 290                 return arch_virt_to_idmap(x);
 291         else
 292                 return __virt_to_phys(x);
 293 }
 294
 295 #define virt_to_idmap(x)        __virt_to_idmap((unsigned long)(x))
 296
 297 /*
 298  * Virtual <-> DMA view memory address translations
 299  * Again, these are *only* valid on the kernel direct mapped RAM
 300  * memory.  Use of these is *deprecated* (and that doesn't mean
 301  * use the __ prefixed forms instead.)  See dma-mapping.h.
 302  */
 303 #ifndef __virt_to_bus
 304 #define __virt_to_bus   __virt_to_phys
 305 #define __bus_to_virt   __phys_to_virt
 306 #define __pfn_to_bus(x) __pfn_to_phys(x)
 307 #define __bus_to_pfn(x) __phys_to_pfn(x)
 308 #endif
 309
 310 #ifdef CONFIG_VIRT_TO_BUS
 311 #define virt_to_bus virt_to_bus
 312 static inline __deprecated unsigned long virt_to_bus(void *x)
 313 {
 314         return __virt_to_bus((unsigned long)x);
 315 }
 316
 317 #define bus_to_virt bus_to_virt
 318 static inline __deprecated void *bus_to_virt(unsigned long x)
 319 {
 320         return (void *)__bus_to_virt(x);
 321 }
 322 #endif
 323
 324 /*
 325  * Conversion between a struct page and a physical address.
 326  *
 327  *  page_to_pfn(page)   convert a struct page * to a PFN number
 328  *  pfn_to_page(pfn)    convert a _valid_ PFN number to struct page *
 329  *
 330  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 331  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 332  */
 333 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 334
 335 #define virt_to_page(kaddr)     pfn_to_page(virt_to_pfn(kaddr))
 336 #define virt_addr_valid(kaddr)  (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
 337                                         && pfn_valid(virt_to_pfn(kaddr)))
 338
 339 #endif
 340
 341 #include <asm-generic/memory_model.h>
 342
 343 #endif