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 #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
 172 extern unsigned long __pv_phys_pfn_offset;
 173 extern u64 __pv_offset;
 174 extern void fixup_pv_table(const void *, unsigned long);
 175 extern 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
 209 static 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
 222 static 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
 241 static inline phys_addr_t __virt_to_phys(unsigned long x)
 242 {
 243         return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
 244 }
 245
 246 static 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
 264 static 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
 270 static 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
 282 extern 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  */
 289 static 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
 296 static 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
 306 static 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
 316 static 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