arch/sh/include/asm/pgtable_32.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_SH_PGTABLE_32_H
   3 #define __ASM_SH_PGTABLE_32_H
   4
   5 /*
   6  * Linux PTEL encoding.
   7  *
   8  * Hardware and software bit definitions for the PTEL value (see below for
   9  * notes on SH-X2 MMUs and 64-bit PTEs):
  10  *
  11  * - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4).
  12  *
  13  * - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the
  14  *   hardware PTEL value can't have the SH-bit set when MMUCR.IX is set,
  15  *   which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT).
  16  *
  17  *   In order to keep this relatively clean, do not use these for defining
  18  *   SH-3 specific flags until all of the other unused bits have been
  19  *   exhausted.
  20  *
  21  * - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE.
  22  *
  23  * - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
  24  *   Bit 10 is used for _PAGE_ACCESSED, and bit 11 is used for _PAGE_SPECIAL.
  25  *
  26  * - On 29 bit platforms, bits 31 to 29 are used for the space attributes
  27  *   and timing control which (together with bit 0) are moved into the
  28  *   old-style PTEA on the parts that support it.
  29  *
  30  * SH-X2 MMUs and extended PTEs
  31  *
  32  * SH-X2 supports an extended mode TLB with split data arrays due to the
  33  * number of bits needed for PR and SZ (now EPR and ESZ) encodings. The PR and
  34  * SZ bit placeholders still exist in data array 1, but are implemented as
  35  * reserved bits, with the real logic existing in data array 2.
  36  *
  37  * The downside to this is that we can no longer fit everything in to a 32-bit
  38  * PTE encoding, so a 64-bit pte_t is necessary for these parts. On the plus
  39  * side, this gives us quite a few spare bits to play with for future usage.
  40  */
  41 /* Legacy and compat mode bits */
  42 #define _PAGE_WT        0x001           /* WT-bit on SH-4, 0 on SH-3 */
  43 #define _PAGE_HW_SHARED 0x002           /* SH-bit  : shared among processes */
  44 #define _PAGE_DIRTY     0x004           /* D-bit   : page changed */
  45 #define _PAGE_CACHABLE  0x008           /* C-bit   : cachable */
  46 #define _PAGE_SZ0       0x010           /* SZ0-bit : Size of page */
  47 #define _PAGE_RW        0x020           /* PR0-bit : write access allowed */
  48 #define _PAGE_USER      0x040           /* PR1-bit : user space access allowed*/
  49 #define _PAGE_SZ1       0x080           /* SZ1-bit : Size of page (on SH-4) */
  50 #define _PAGE_PRESENT   0x100           /* V-bit   : page is valid */
  51 #define _PAGE_PROTNONE  0x200           /* software: if not present  */
  52 #define _PAGE_ACCESSED  0x400           /* software: page referenced */
  53 #define _PAGE_SPECIAL   0x800           /* software: special page */
  54
  55 #define _PAGE_SZ_MASK   (_PAGE_SZ0 | _PAGE_SZ1)
  56 #define _PAGE_PR_MASK   (_PAGE_RW | _PAGE_USER)
  57
  58 /* Extended mode bits */
  59 #define _PAGE_EXT_ESZ0          0x0010  /* ESZ0-bit: Size of page */
  60 #define _PAGE_EXT_ESZ1          0x0020  /* ESZ1-bit: Size of page */
  61 #define _PAGE_EXT_ESZ2          0x0040  /* ESZ2-bit: Size of page */
  62 #define _PAGE_EXT_ESZ3          0x0080  /* ESZ3-bit: Size of page */
  63
  64 #define _PAGE_EXT_USER_EXEC     0x0100  /* EPR0-bit: User space executable */
  65 #define _PAGE_EXT_USER_WRITE    0x0200  /* EPR1-bit: User space writable */
  66 #define _PAGE_EXT_USER_READ     0x0400  /* EPR2-bit: User space readable */
  67
  68 #define _PAGE_EXT_KERN_EXEC     0x0800  /* EPR3-bit: Kernel space executable */
  69 #define _PAGE_EXT_KERN_WRITE    0x1000  /* EPR4-bit: Kernel space writable */
  70 #define _PAGE_EXT_KERN_READ     0x2000  /* EPR5-bit: Kernel space readable */
  71
  72 #define _PAGE_EXT_WIRED         0x4000  /* software: Wire TLB entry */
  73
  74 /* Wrapper for extended mode pgprot twiddling */
  75 #define _PAGE_EXT(x)            ((unsigned long long)(x) << 32)
  76
  77 #ifdef CONFIG_X2TLB
  78 #define _PAGE_PCC_MASK  0x00000000      /* No legacy PTEA support */
  79 #else
  80
  81 /* software: moves to PTEA.TC (Timing Control) */
  82 #define _PAGE_PCC_AREA5 0x00000000      /* use BSC registers for area5 */
  83 #define _PAGE_PCC_AREA6 0x80000000      /* use BSC registers for area6 */
  84
  85 /* software: moves to PTEA.SA[2:0] (Space Attributes) */
  86 #define _PAGE_PCC_IODYN 0x00000001      /* IO space, dynamically sized bus */
  87 #define _PAGE_PCC_IO8   0x20000000      /* IO space, 8 bit bus */
  88 #define _PAGE_PCC_IO16  0x20000001      /* IO space, 16 bit bus */
  89 #define _PAGE_PCC_COM8  0x40000000      /* Common Memory space, 8 bit bus */
  90 #define _PAGE_PCC_COM16 0x40000001      /* Common Memory space, 16 bit bus */
  91 #define _PAGE_PCC_ATR8  0x60000000      /* Attribute Memory space, 8 bit bus */
  92 #define _PAGE_PCC_ATR16 0x60000001      /* Attribute Memory space, 6 bit bus */
  93
  94 #define _PAGE_PCC_MASK  0xe0000001
  95
  96 /* copy the ptea attributes */
  97 static inline unsigned long copy_ptea_attributes(unsigned long x)
  98 {
  99         return  ((x >> 28) & 0xe) | (x & 0x1);
 100 }
 101 #endif
 102
 103 /* Mask which drops unused bits from the PTEL value */
 104 #if defined(CONFIG_CPU_SH3)
 105 #define _PAGE_CLEAR_FLAGS       (_PAGE_PROTNONE | _PAGE_ACCESSED| \
 106                                   _PAGE_SZ1     | _PAGE_HW_SHARED)
 107 #elif defined(CONFIG_X2TLB)
 108 /* Get rid of the legacy PR/SZ bits when using extended mode */
 109 #define _PAGE_CLEAR_FLAGS       (_PAGE_PROTNONE | _PAGE_ACCESSED | \
 110                                  _PAGE_PR_MASK | _PAGE_SZ_MASK)
 111 #else
 112 #define _PAGE_CLEAR_FLAGS       (_PAGE_PROTNONE | _PAGE_ACCESSED)
 113 #endif
 114
 115 #define _PAGE_FLAGS_HARDWARE_MASK       (phys_addr_mask() & ~(_PAGE_CLEAR_FLAGS))
 116
 117 /* Hardware flags, page size encoding */
 118 #if !defined(CONFIG_MMU)
 119 # define _PAGE_FLAGS_HARD       0ULL
 120 #elif defined(CONFIG_X2TLB)
 121 # if defined(CONFIG_PAGE_SIZE_4KB)
 122 #  define _PAGE_FLAGS_HARD      _PAGE_EXT(_PAGE_EXT_ESZ0)
 123 # elif defined(CONFIG_PAGE_SIZE_8KB)
 124 #  define _PAGE_FLAGS_HARD      _PAGE_EXT(_PAGE_EXT_ESZ1)
 125 # elif defined(CONFIG_PAGE_SIZE_64KB)
 126 #  define _PAGE_FLAGS_HARD      _PAGE_EXT(_PAGE_EXT_ESZ2)
 127 # endif
 128 #else
 129 # if defined(CONFIG_PAGE_SIZE_4KB)
 130 #  define _PAGE_FLAGS_HARD      _PAGE_SZ0
 131 # elif defined(CONFIG_PAGE_SIZE_64KB)
 132 #  define _PAGE_FLAGS_HARD      _PAGE_SZ1
 133 # endif
 134 #endif
 135
 136 #if defined(CONFIG_X2TLB)
 137 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
 138 #  define _PAGE_SZHUGE  (_PAGE_EXT_ESZ2)
 139 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K)
 140 #  define _PAGE_SZHUGE  (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ2)
 141 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
 142 #  define _PAGE_SZHUGE  (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ1 | _PAGE_EXT_ESZ2)
 143 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
 144 #  define _PAGE_SZHUGE  (_PAGE_EXT_ESZ3)
 145 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB)
 146 #  define _PAGE_SZHUGE  (_PAGE_EXT_ESZ2 | _PAGE_EXT_ESZ3)
 147 # endif
 148 # define _PAGE_WIRED    (_PAGE_EXT(_PAGE_EXT_WIRED))
 149 #else
 150 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
 151 #  define _PAGE_SZHUGE  (_PAGE_SZ1)
 152 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
 153 #  define _PAGE_SZHUGE  (_PAGE_SZ0 | _PAGE_SZ1)
 154 # endif
 155 # define _PAGE_WIRED    (0)
 156 #endif
 157
 158 /*
 159  * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
 160  * to make pte_mkhuge() happy.
 161  */
 162 #ifndef _PAGE_SZHUGE
 163 # define _PAGE_SZHUGE   (_PAGE_FLAGS_HARD)
 164 #endif
 165
 166 /*
 167  * Mask of bits that are to be preserved across pgprot changes.
 168  */
 169 #define _PAGE_CHG_MASK \
 170         (PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | \
 171          _PAGE_DIRTY | _PAGE_SPECIAL)
 172
 173 #ifndef __ASSEMBLY__
 174
 175 #if defined(CONFIG_X2TLB) /* SH-X2 TLB */
 176 #define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
 177                                  _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
 178
 179 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
 180                                  _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
 181                                  _PAGE_EXT(_PAGE_EXT_KERN_READ  | \
 182                                            _PAGE_EXT_KERN_WRITE | \
 183                                            _PAGE_EXT_USER_READ  | \
 184                                            _PAGE_EXT_USER_WRITE))
 185
 186 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
 187                                  _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
 188                                  _PAGE_EXT(_PAGE_EXT_KERN_EXEC | \
 189                                            _PAGE_EXT_KERN_READ | \
 190                                            _PAGE_EXT_USER_EXEC | \
 191                                            _PAGE_EXT_USER_READ))
 192
 193 #define PAGE_COPY       PAGE_EXECREAD
 194
 195 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
 196                                  _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
 197                                  _PAGE_EXT(_PAGE_EXT_KERN_READ | \
 198                                            _PAGE_EXT_USER_READ))
 199
 200 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
 201                                  _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
 202                                  _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
 203                                            _PAGE_EXT_USER_WRITE))
 204
 205 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
 206                                  _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
 207                                  _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
 208                                            _PAGE_EXT_KERN_READ  | \
 209                                            _PAGE_EXT_KERN_EXEC  | \
 210                                            _PAGE_EXT_USER_WRITE | \
 211                                            _PAGE_EXT_USER_READ  | \
 212                                            _PAGE_EXT_USER_EXEC))
 213
 214 #define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
 215                                  _PAGE_DIRTY | _PAGE_ACCESSED | \
 216                                  _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
 217                                  _PAGE_EXT(_PAGE_EXT_KERN_READ | \
 218                                            _PAGE_EXT_KERN_WRITE | \
 219                                            _PAGE_EXT_KERN_EXEC))
 220
 221 #define PAGE_KERNEL_NOCACHE \
 222                         __pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \
 223                                  _PAGE_ACCESSED | _PAGE_HW_SHARED | \
 224                                  _PAGE_FLAGS_HARD | \
 225                                  _PAGE_EXT(_PAGE_EXT_KERN_READ | \
 226                                            _PAGE_EXT_KERN_WRITE | \
 227                                            _PAGE_EXT_KERN_EXEC))
 228
 229 #define PAGE_KERNEL_RO  __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
 230                                  _PAGE_DIRTY | _PAGE_ACCESSED | \
 231                                  _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
 232                                  _PAGE_EXT(_PAGE_EXT_KERN_READ | \
 233                                            _PAGE_EXT_KERN_EXEC))
 234
 235 #define PAGE_KERNEL_PCC(slot, type) \
 236                         __pgprot(0)
 237
 238 #elif defined(CONFIG_MMU) /* SH-X TLB */
 239 #define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
 240                                  _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
 241
 242 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
 243                                  _PAGE_CACHABLE | _PAGE_ACCESSED | \
 244                                  _PAGE_FLAGS_HARD)
 245
 246 #define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
 247                                  _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
 248
 249 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
 250                                  _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
 251
 252 #define PAGE_EXECREAD   PAGE_READONLY
 253 #define PAGE_RWX        PAGE_SHARED
 254 #define PAGE_WRITEONLY  PAGE_SHARED
 255
 256 #define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | \
 257                                  _PAGE_DIRTY | _PAGE_ACCESSED | \
 258                                  _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
 259
 260 #define PAGE_KERNEL_NOCACHE \
 261                         __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
 262                                  _PAGE_ACCESSED | _PAGE_HW_SHARED | \
 263                                  _PAGE_FLAGS_HARD)
 264
 265 #define PAGE_KERNEL_RO  __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
 266                                  _PAGE_DIRTY | _PAGE_ACCESSED | \
 267                                  _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
 268
 269 #define PAGE_KERNEL_PCC(slot, type) \
 270                         __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
 271                                  _PAGE_ACCESSED | _PAGE_FLAGS_HARD | \
 272                                  (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \
 273                                  (type))
 274 #else /* no mmu */
 275 #define PAGE_NONE               __pgprot(0)
 276 #define PAGE_SHARED             __pgprot(0)
 277 #define PAGE_COPY               __pgprot(0)
 278 #define PAGE_EXECREAD           __pgprot(0)
 279 #define PAGE_RWX                __pgprot(0)
 280 #define PAGE_READONLY           __pgprot(0)
 281 #define PAGE_WRITEONLY          __pgprot(0)
 282 #define PAGE_KERNEL             __pgprot(0)
 283 #define PAGE_KERNEL_NOCACHE     __pgprot(0)
 284 #define PAGE_KERNEL_RO          __pgprot(0)
 285
 286 #define PAGE_KERNEL_PCC(slot, type) \
 287                                 __pgprot(0)
 288 #endif
 289
 290 #endif /* __ASSEMBLY__ */
 291
 292 #ifndef __ASSEMBLY__
 293
 294 /*
 295  * Certain architectures need to do special things when PTEs
 296  * within a page table are directly modified.  Thus, the following
 297  * hook is made available.
 298  */
 299 #ifdef CONFIG_X2TLB
 300 static inline void set_pte(pte_t *ptep, pte_t pte)
 301 {
 302         ptep->pte_high = pte.pte_high;
 303         smp_wmb();
 304         ptep->pte_low = pte.pte_low;
 305 }
 306 #else
 307 #define set_pte(pteptr, pteval) (*(pteptr) = pteval)
 308 #endif
 309
 310 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 311
 312 /*
 313  * (pmds are folded into pgds so this doesn't get actually called,
 314  * but the define is needed for a generic inline function.)
 315  */
 316 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
 317
 318 #define pfn_pte(pfn, prot) \
 319         __pte(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 320 #define pfn_pmd(pfn, prot) \
 321         __pmd(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 322
 323 #define pte_none(x)             (!pte_val(x))
 324 #define pte_present(x)          ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE))
 325
 326 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
 327
 328 #define pmd_none(x)     (!pmd_val(x))
 329 #define pmd_present(x)  (pmd_val(x))
 330 #define pmd_clear(xp)   do { set_pmd(xp, __pmd(0)); } while (0)
 331 #define pmd_bad(x)      (pmd_val(x) & ~PAGE_MASK)
 332
 333 #define pages_to_mb(x)  ((x) >> (20-PAGE_SHIFT))
 334 #define pte_page(x)     pfn_to_page(pte_pfn(x))
 335
 336 /*
 337  * The following only work if pte_present() is true.
 338  * Undefined behaviour if not..
 339  */
 340 #define pte_not_present(pte)    (!((pte).pte_low & _PAGE_PRESENT))
 341 #define pte_dirty(pte)          ((pte).pte_low & _PAGE_DIRTY)
 342 #define pte_young(pte)          ((pte).pte_low & _PAGE_ACCESSED)
 343 #define pte_special(pte)        ((pte).pte_low & _PAGE_SPECIAL)
 344
 345 #ifdef CONFIG_X2TLB
 346 #define pte_write(pte) \
 347         ((pte).pte_high & (_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE))
 348 #else
 349 #define pte_write(pte)          ((pte).pte_low & _PAGE_RW)
 350 #endif
 351
 352 #define PTE_BIT_FUNC(h,fn,op) \
 353 static inline pte_t pte_##fn(pte_t pte) { pte.pte_##h op; return pte; }
 354
 355 #ifdef CONFIG_X2TLB
 356 /*
 357  * We cheat a bit in the SH-X2 TLB case. As the permission bits are
 358  * individually toggled (and user permissions are entirely decoupled from
 359  * kernel permissions), we attempt to couple them a bit more sanely here.
 360  */
 361 PTE_BIT_FUNC(high, wrprotect, &= ~(_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE));
 362 PTE_BIT_FUNC(high, mkwrite, |= _PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE);
 363 PTE_BIT_FUNC(high, mkhuge, |= _PAGE_SZHUGE);
 364 #else
 365 PTE_BIT_FUNC(low, wrprotect, &= ~_PAGE_RW);
 366 PTE_BIT_FUNC(low, mkwrite, |= _PAGE_RW);
 367 PTE_BIT_FUNC(low, mkhuge, |= _PAGE_SZHUGE);
 368 #endif
 369
 370 PTE_BIT_FUNC(low, mkclean, &= ~_PAGE_DIRTY);
 371 PTE_BIT_FUNC(low, mkdirty, |= _PAGE_DIRTY);
 372 PTE_BIT_FUNC(low, mkold, &= ~_PAGE_ACCESSED);
 373 PTE_BIT_FUNC(low, mkyoung, |= _PAGE_ACCESSED);
 374 PTE_BIT_FUNC(low, mkspecial, |= _PAGE_SPECIAL);
 375
 376 /*
 377  * Macro and implementation to make a page protection as uncachable.
 378  */
 379 #define pgprot_writecombine(prot) \
 380         __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
 381
 382 #define pgprot_noncached         pgprot_writecombine
 383
 384 /*
 385  * Conversion functions: convert a page and protection to a page entry,
 386  * and a page entry and page directory to the page they refer to.
 387  *
 388  * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
 389  */
 390 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 391
 392 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 393 {
 394         pte.pte_low &= _PAGE_CHG_MASK;
 395         pte.pte_low |= pgprot_val(newprot);
 396
 397 #ifdef CONFIG_X2TLB
 398         pte.pte_high |= pgprot_val(newprot) >> 32;
 399 #endif
 400
 401         return pte;
 402 }
 403
 404 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 405 {
 406         return (unsigned long)pmd_val(pmd);
 407 }
 408
 409 #define pmd_page(pmd)           (virt_to_page(pmd_val(pmd)))
 410
 411 #ifdef CONFIG_X2TLB
 412 #define pte_ERROR(e) \
 413         printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, \
 414                &(e), (e).pte_high, (e).pte_low)
 415 #define pgd_ERROR(e) \
 416         printk("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
 417 #else
 418 #define pte_ERROR(e) \
 419         printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
 420 #define pgd_ERROR(e) \
 421         printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
 422 #endif
 423
 424 /*
 425  * Encode and de-code a swap entry
 426  *
 427  * Constraints:
 428  *      _PAGE_PRESENT at bit 8
 429  *      _PAGE_PROTNONE at bit 9
 430  *
 431  * For the normal case, we encode the swap type into bits 0:7 and the
 432  * swap offset into bits 10:30. For the 64-bit PTE case, we keep the
 433  * preserved bits in the low 32-bits and use the upper 32 as the swap
 434  * offset (along with a 5-bit type), following the same approach as x86
 435  * PAE. This keeps the logic quite simple.
 436  *
 437  * As is evident by the Alpha code, if we ever get a 64-bit unsigned
 438  * long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes
 439  * much cleaner..
 440  *
 441  * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
 442  *       and _PAGE_PROTNONE bits
 443  */
 444 #ifdef CONFIG_X2TLB
 445 #define __swp_type(x)                   ((x).val & 0x1f)
 446 #define __swp_offset(x)                 ((x).val >> 5)
 447 #define __swp_entry(type, offset)       ((swp_entry_t){ (type) | (offset) << 5})
 448 #define __pte_to_swp_entry(pte)         ((swp_entry_t){ (pte).pte_high })
 449 #define __swp_entry_to_pte(x)           ((pte_t){ 0, (x).val })
 450
 451 #else
 452 #define __swp_type(x)                   ((x).val & 0xff)
 453 #define __swp_offset(x)                 ((x).val >> 10)
 454 #define __swp_entry(type, offset)       ((swp_entry_t){(type) | (offset) <<10})
 455
 456 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) >> 1 })
 457 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val << 1 })
 458 #endif
 459
 460 #endif /* __ASSEMBLY__ */
 461 #endif /* __ASM_SH_PGTABLE_32_H */