include/asm-powerpc/pgtable-ppc32.h

   1 #ifndef _ASM_POWERPC_PGTABLE_PPC32_H
   2 #define _ASM_POWERPC_PGTABLE_PPC32_H
   3
   4 #include <asm-generic/pgtable-nopmd.h>
   5
   6 #ifndef __ASSEMBLY__
   7 #include <linux/sched.h>
   8 #include <linux/threads.h>
   9 #include <asm/io.h>                     /* For sub-arch specific PPC_PIN_SIZE */
  10
  11 extern unsigned long va_to_phys(unsigned long address);
  12 extern pte_t *va_to_pte(unsigned long address);
  13 extern unsigned long ioremap_bot, ioremap_base;
  14
  15 #ifdef CONFIG_44x
  16 extern int icache_44x_need_flush;
  17 #endif
  18
  19 #endif /* __ASSEMBLY__ */
  20
  21 /*
  22  * The PowerPC MMU uses a hash table containing PTEs, together with
  23  * a set of 16 segment registers (on 32-bit implementations), to define
  24  * the virtual to physical address mapping.
  25  *
  26  * We use the hash table as an extended TLB, i.e. a cache of currently
  27  * active mappings.  We maintain a two-level page table tree, much
  28  * like that used by the i386, for the sake of the Linux memory
  29  * management code.  Low-level assembler code in hashtable.S
  30  * (procedure hash_page) is responsible for extracting ptes from the
  31  * tree and putting them into the hash table when necessary, and
  32  * updating the accessed and modified bits in the page table tree.
  33  */
  34
  35 /*
  36  * The PowerPC MPC8xx uses a TLB with hardware assisted, software tablewalk.
  37  * We also use the two level tables, but we can put the real bits in them
  38  * needed for the TLB and tablewalk.  These definitions require Mx_CTR.PPM = 0,
  39  * Mx_CTR.PPCS = 0, and MD_CTR.TWAM = 1.  The level 2 descriptor has
  40  * additional page protection (when Mx_CTR.PPCS = 1) that allows TLB hit
  41  * based upon user/super access.  The TLB does not have accessed nor write
  42  * protect.  We assume that if the TLB get loaded with an entry it is
  43  * accessed, and overload the changed bit for write protect.  We use
  44  * two bits in the software pte that are supposed to be set to zero in
  45  * the TLB entry (24 and 25) for these indicators.  Although the level 1
  46  * descriptor contains the guarded and writethrough/copyback bits, we can
  47  * set these at the page level since they get copied from the Mx_TWC
  48  * register when the TLB entry is loaded.  We will use bit 27 for guard, since
  49  * that is where it exists in the MD_TWC, and bit 26 for writethrough.
  50  * These will get masked from the level 2 descriptor at TLB load time, and
  51  * copied to the MD_TWC before it gets loaded.
  52  * Large page sizes added.  We currently support two sizes, 4K and 8M.
  53  * This also allows a TLB hander optimization because we can directly
  54  * load the PMD into MD_TWC.  The 8M pages are only used for kernel
  55  * mapping of well known areas.  The PMD (PGD) entries contain control
  56  * flags in addition to the address, so care must be taken that the
  57  * software no longer assumes these are only pointers.
  58  */
  59
  60 /*
  61  * At present, all PowerPC 400-class processors share a similar TLB
  62  * architecture. The instruction and data sides share a unified,
  63  * 64-entry, fully-associative TLB which is maintained totally under
  64  * software control. In addition, the instruction side has a
  65  * hardware-managed, 4-entry, fully-associative TLB which serves as a
  66  * first level to the shared TLB. These two TLBs are known as the UTLB
  67  * and ITLB, respectively (see "mmu.h" for definitions).
  68  */
  69
  70 /*
  71  * The normal case is that PTEs are 32-bits and we have a 1-page
  72  * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
  73  *
  74  * For any >32-bit physical address platform, we can use the following
  75  * two level page table layout where the pgdir is 8KB and the MS 13 bits
  76  * are an index to the second level table.  The combined pgdir/pmd first
  77  * level has 2048 entries and the second level has 512 64-bit PTE entries.
  78  * -Matt
  79  */
  80 /* PGDIR_SHIFT determines what a top-level page table entry can map */
  81 #define PGDIR_SHIFT     (PAGE_SHIFT + PTE_SHIFT)
  82 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  83 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
  84
  85 /*
  86  * entries per page directory level: our page-table tree is two-level, so
  87  * we don't really have any PMD directory.
  88  */
  89 #ifndef __ASSEMBLY__
  90 #define PTE_TABLE_SIZE  (sizeof(pte_t) << PTE_SHIFT)
  91 #define PGD_TABLE_SIZE  (sizeof(pgd_t) << (32 - PGDIR_SHIFT))
  92 #endif  /* __ASSEMBLY__ */
  93
  94 #define PTRS_PER_PTE    (1 << PTE_SHIFT)
  95 #define PTRS_PER_PMD    1
  96 #define PTRS_PER_PGD    (1 << (32 - PGDIR_SHIFT))
  97
  98 #define USER_PTRS_PER_PGD       (TASK_SIZE / PGDIR_SIZE)
  99 #define FIRST_USER_ADDRESS      0
 100
 101 #define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
 102 #define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS)
 103
 104 #define pte_ERROR(e) \
 105         printk("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
 106                 (unsigned long long)pte_val(e))
 107 #define pgd_ERROR(e) \
 108         printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
 109
 110 /*
 111  * Just any arbitrary offset to the start of the vmalloc VM area: the
 112  * current 64MB value just means that there will be a 64MB "hole" after the
 113  * physical memory until the kernel virtual memory starts.  That means that
 114  * any out-of-bounds memory accesses will hopefully be caught.
 115  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
 116  * area for the same reason. ;)
 117  *
 118  * We no longer map larger than phys RAM with the BATs so we don't have
 119  * to worry about the VMALLOC_OFFSET causing problems.  We do have to worry
 120  * about clashes between our early calls to ioremap() that start growing down
 121  * from ioremap_base being run into the VM area allocations (growing upwards
 122  * from VMALLOC_START).  For this reason we have ioremap_bot to check when
 123  * we actually run into our mappings setup in the early boot with the VM
 124  * system.  This really does become a problem for machines with good amounts
 125  * of RAM.  -- Cort
 126  */
 127 #define VMALLOC_OFFSET (0x1000000) /* 16M */
 128 #ifdef PPC_PIN_SIZE
 129 #define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
 130 #else
 131 #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
 132 #endif
 133 #define VMALLOC_END     ioremap_bot
 134
 135 /*
 136  * Bits in a linux-style PTE.  These match the bits in the
 137  * (hardware-defined) PowerPC PTE as closely as possible.
 138  */
 139
 140 #if defined(CONFIG_40x)
 141
 142 /* There are several potential gotchas here.  The 40x hardware TLBLO
 143    field looks like this:
 144
 145    0  1  2  3  4  ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31
 146    RPN.....................  0  0 EX WR ZSEL.......  W  I  M  G
 147
 148    Where possible we make the Linux PTE bits match up with this
 149
 150    - bits 20 and 21 must be cleared, because we use 4k pages (40x can
 151      support down to 1k pages), this is done in the TLBMiss exception
 152      handler.
 153    - We use only zones 0 (for kernel pages) and 1 (for user pages)
 154      of the 16 available.  Bit 24-26 of the TLB are cleared in the TLB
 155      miss handler.  Bit 27 is PAGE_USER, thus selecting the correct
 156      zone.
 157    - PRESENT *must* be in the bottom two bits because swap cache
 158      entries use the top 30 bits.  Because 40x doesn't support SMP
 159      anyway, M is irrelevant so we borrow it for PAGE_PRESENT.  Bit 30
 160      is cleared in the TLB miss handler before the TLB entry is loaded.
 161    - All other bits of the PTE are loaded into TLBLO without
 162      modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for
 163      software PTE bits.  We actually use use bits 21, 24, 25, and
 164      30 respectively for the software bits: ACCESSED, DIRTY, RW, and
 165      PRESENT.
 166 */
 167
 168 /* Definitions for 40x embedded chips. */
 169 #define _PAGE_GUARDED   0x001   /* G: page is guarded from prefetch */
 170 #define _PAGE_FILE      0x001   /* when !present: nonlinear file mapping */
 171 #define _PAGE_PRESENT   0x002   /* software: PTE contains a translation */
 172 #define _PAGE_NO_CACHE  0x004   /* I: caching is inhibited */
 173 #define _PAGE_WRITETHRU 0x008   /* W: caching is write-through */
 174 #define _PAGE_USER      0x010   /* matches one of the zone permission bits */
 175 #define _PAGE_RW        0x040   /* software: Writes permitted */
 176 #define _PAGE_DIRTY     0x080   /* software: dirty page */
 177 #define _PAGE_HWWRITE   0x100   /* hardware: Dirty & RW, set in exception */
 178 #define _PAGE_HWEXEC    0x200   /* hardware: EX permission */
 179 #define _PAGE_ACCESSED  0x400   /* software: R: page referenced */
 180
 181 #define _PMD_PRESENT    0x400   /* PMD points to page of PTEs */
 182 #define _PMD_BAD        0x802
 183 #define _PMD_SIZE       0x0e0   /* size field, != 0 for large-page PMD entry */
 184 #define _PMD_SIZE_4M    0x0c0
 185 #define _PMD_SIZE_16M   0x0e0
 186 #define PMD_PAGE_SIZE(pmdval)   (1024 << (((pmdval) & _PMD_SIZE) >> 4))
 187
 188 #elif defined(CONFIG_44x)
 189 /*
 190  * Definitions for PPC440
 191  *
 192  * Because of the 3 word TLB entries to support 36-bit addressing,
 193  * the attribute are difficult to map in such a fashion that they
 194  * are easily loaded during exception processing.  I decided to
 195  * organize the entry so the ERPN is the only portion in the
 196  * upper word of the PTE and the attribute bits below are packed
 197  * in as sensibly as they can be in the area below a 4KB page size
 198  * oriented RPN.  This at least makes it easy to load the RPN and
 199  * ERPN fields in the TLB. -Matt
 200  *
 201  * Note that these bits preclude future use of a page size
 202  * less than 4KB.
 203  *
 204  *
 205  * PPC 440 core has following TLB attribute fields;
 206  *
 207  *   TLB1:
 208  *   0  1  2  3  4  ... 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
 209  *   RPN.................................  -  -  -  -  -  - ERPN.......
 210  *
 211  *   TLB2:
 212  *   0  1  2  3  4  ... 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
 213  *   -  -  -  -  -    - U0 U1 U2 U3 W  I  M  G  E   - UX UW UR SX SW SR
 214  *
 215  * There are some constrains and options, to decide mapping software bits
 216  * into TLB entry.
 217  *
 218  *   - PRESENT *must* be in the bottom three bits because swap cache
 219  *     entries use the top 29 bits for TLB2.
 220  *
 221  *   - FILE *must* be in the bottom three bits because swap cache
 222  *     entries use the top 29 bits for TLB2.
 223  *
 224  *   - CACHE COHERENT bit (M) has no effect on PPC440 core, because it
 225  *     doesn't support SMP. So we can use this as software bit, like
 226  *     DIRTY.
 227  *
 228  * With the PPC 44x Linux implementation, the 0-11th LSBs of the PTE are used
 229  * for memory protection related functions (see PTE structure in
 230  * include/asm-ppc/mmu.h).  The _PAGE_XXX definitions in this file map to the
 231  * above bits.  Note that the bit values are CPU specific, not architecture
 232  * specific.
 233  *
 234  * The kernel PTE entry holds an arch-dependent swp_entry structure under
 235  * certain situations. In other words, in such situations some portion of
 236  * the PTE bits are used as a swp_entry. In the PPC implementation, the
 237  * 3-24th LSB are shared with swp_entry, however the 0-2nd three LSB still
 238  * hold protection values. That means the three protection bits are
 239  * reserved for both PTE and SWAP entry at the most significant three
 240  * LSBs.
 241  *
 242  * There are three protection bits available for SWAP entry:
 243  *      _PAGE_PRESENT
 244  *      _PAGE_FILE
 245  *      _PAGE_HASHPTE (if HW has)
 246  *
 247  * So those three bits have to be inside of 0-2nd LSB of PTE.
 248  *
 249  */
 250
 251 #define _PAGE_PRESENT   0x00000001              /* S: PTE valid */
 252 #define _PAGE_RW        0x00000002              /* S: Write permission */
 253 #define _PAGE_FILE      0x00000004              /* S: nonlinear file mapping */
 254 #define _PAGE_ACCESSED  0x00000008              /* S: Page referenced */
 255 #define _PAGE_HWWRITE   0x00000010              /* H: Dirty & RW */
 256 #define _PAGE_HWEXEC    0x00000020              /* H: Execute permission */
 257 #define _PAGE_USER      0x00000040              /* S: User page */
 258 #define _PAGE_ENDIAN    0x00000080              /* H: E bit */
 259 #define _PAGE_GUARDED   0x00000100              /* H: G bit */
 260 #define _PAGE_DIRTY     0x00000200              /* S: Page dirty */
 261 #define _PAGE_NO_CACHE  0x00000400              /* H: I bit */
 262 #define _PAGE_WRITETHRU 0x00000800              /* H: W bit */
 263
 264 /* TODO: Add large page lowmem mapping support */
 265 #define _PMD_PRESENT    0
 266 #define _PMD_PRESENT_MASK (PAGE_MASK)
 267 #define _PMD_BAD        (~PAGE_MASK)
 268
 269 /* ERPN in a PTE never gets cleared, ignore it */
 270 #define _PTE_NONE_MASK  0xffffffff00000000ULL
 271
 272 #elif defined(CONFIG_FSL_BOOKE)
 273 /*
 274    MMU Assist Register 3:
 275
 276    32 33 34 35 36  ... 50 51 52 53 54 55 56 57 58 59 60 61 62 63
 277    RPN......................  0  0 U0 U1 U2 U3 UX SX UW SW UR SR
 278
 279    - PRESENT *must* be in the bottom three bits because swap cache
 280      entries use the top 29 bits.
 281
 282    - FILE *must* be in the bottom three bits because swap cache
 283      entries use the top 29 bits.
 284 */
 285
 286 /* Definitions for FSL Book-E Cores */
 287 #define _PAGE_PRESENT   0x00001 /* S: PTE contains a translation */
 288 #define _PAGE_USER      0x00002 /* S: User page (maps to UR) */
 289 #define _PAGE_FILE      0x00002 /* S: when !present: nonlinear file mapping */
 290 #define _PAGE_ACCESSED  0x00004 /* S: Page referenced */
 291 #define _PAGE_HWWRITE   0x00008 /* H: Dirty & RW, set in exception */
 292 #define _PAGE_RW        0x00010 /* S: Write permission */
 293 #define _PAGE_HWEXEC    0x00020 /* H: UX permission */
 294
 295 #define _PAGE_ENDIAN    0x00040 /* H: E bit */
 296 #define _PAGE_GUARDED   0x00080 /* H: G bit */
 297 #define _PAGE_COHERENT  0x00100 /* H: M bit */
 298 #define _PAGE_NO_CACHE  0x00200 /* H: I bit */
 299 #define _PAGE_WRITETHRU 0x00400 /* H: W bit */
 300
 301 #ifdef CONFIG_PTE_64BIT
 302 #define _PAGE_DIRTY     0x08000 /* S: Page dirty */
 303
 304 /* ERPN in a PTE never gets cleared, ignore it */
 305 #define _PTE_NONE_MASK  0xffffffffffff0000ULL
 306 #else
 307 #define _PAGE_DIRTY     0x00800 /* S: Page dirty */
 308 #endif
 309
 310 #define _PMD_PRESENT    0
 311 #define _PMD_PRESENT_MASK (PAGE_MASK)
 312 #define _PMD_BAD        (~PAGE_MASK)
 313
 314 #elif defined(CONFIG_8xx)
 315 /* Definitions for 8xx embedded chips. */
 316 #define _PAGE_PRESENT   0x0001  /* Page is valid */
 317 #define _PAGE_FILE      0x0002  /* when !present: nonlinear file mapping */
 318 #define _PAGE_NO_CACHE  0x0002  /* I: cache inhibit */
 319 #define _PAGE_SHARED    0x0004  /* No ASID (context) compare */
 320
 321 /* These five software bits must be masked out when the entry is loaded
 322  * into the TLB.
 323  */
 324 #define _PAGE_EXEC      0x0008  /* software: i-cache coherency required */
 325 #define _PAGE_GUARDED   0x0010  /* software: guarded access */
 326 #define _PAGE_DIRTY     0x0020  /* software: page changed */
 327 #define _PAGE_RW        0x0040  /* software: user write access allowed */
 328 #define _PAGE_ACCESSED  0x0080  /* software: page referenced */
 329
 330 /* Setting any bits in the nibble with the follow two controls will
 331  * require a TLB exception handler change.  It is assumed unused bits
 332  * are always zero.
 333  */
 334 #define _PAGE_HWWRITE   0x0100  /* h/w write enable: never set in Linux PTE */
 335 #define _PAGE_USER      0x0800  /* One of the PP bits, the other is USER&~RW */
 336
 337 #define _PMD_PRESENT    0x0001
 338 #define _PMD_BAD        0x0ff0
 339 #define _PMD_PAGE_MASK  0x000c
 340 #define _PMD_PAGE_8M    0x000c
 341
 342 /*
 343  * The 8xx TLB miss handler allegedly sets _PAGE_ACCESSED in the PTE
 344  * for an address even if _PAGE_PRESENT is not set, as a performance
 345  * optimization.  This is a bug if you ever want to use swap unless
 346  * _PAGE_ACCESSED is 2, which it isn't, or unless you have 8xx-specific
 347  * definitions for __swp_entry etc. below, which would be gross.
 348  *  -- paulus
 349  */
 350 #define _PTE_NONE_MASK _PAGE_ACCESSED
 351
 352 #else /* CONFIG_6xx */
 353 /* Definitions for 60x, 740/750, etc. */
 354 #define _PAGE_PRESENT   0x001   /* software: pte contains a translation */
 355 #define _PAGE_HASHPTE   0x002   /* hash_page has made an HPTE for this pte */
 356 #define _PAGE_FILE      0x004   /* when !present: nonlinear file mapping */
 357 #define _PAGE_USER      0x004   /* usermode access allowed */
 358 #define _PAGE_GUARDED   0x008   /* G: prohibit speculative access */
 359 #define _PAGE_COHERENT  0x010   /* M: enforce memory coherence (SMP systems) */
 360 #define _PAGE_NO_CACHE  0x020   /* I: cache inhibit */
 361 #define _PAGE_WRITETHRU 0x040   /* W: cache write-through */
 362 #define _PAGE_DIRTY     0x080   /* C: page changed */
 363 #define _PAGE_ACCESSED  0x100   /* R: page referenced */
 364 #define _PAGE_EXEC      0x200   /* software: i-cache coherency required */
 365 #define _PAGE_RW        0x400   /* software: user write access allowed */
 366
 367 #define _PTE_NONE_MASK  _PAGE_HASHPTE
 368
 369 #define _PMD_PRESENT    0
 370 #define _PMD_PRESENT_MASK (PAGE_MASK)
 371 #define _PMD_BAD        (~PAGE_MASK)
 372 #endif
 373
 374 /*
 375  * Some bits are only used on some cpu families...
 376  */
 377 #ifndef _PAGE_HASHPTE
 378 #define _PAGE_HASHPTE   0
 379 #endif
 380 #ifndef _PTE_NONE_MASK
 381 #define _PTE_NONE_MASK 0
 382 #endif
 383 #ifndef _PAGE_SHARED
 384 #define _PAGE_SHARED    0
 385 #endif
 386 #ifndef _PAGE_HWWRITE
 387 #define _PAGE_HWWRITE   0
 388 #endif
 389 #ifndef _PAGE_HWEXEC
 390 #define _PAGE_HWEXEC    0
 391 #endif
 392 #ifndef _PAGE_EXEC
 393 #define _PAGE_EXEC      0
 394 #endif
 395 #ifndef _PMD_PRESENT_MASK
 396 #define _PMD_PRESENT_MASK       _PMD_PRESENT
 397 #endif
 398 #ifndef _PMD_SIZE
 399 #define _PMD_SIZE       0
 400 #define PMD_PAGE_SIZE(pmd)      bad_call_to_PMD_PAGE_SIZE()
 401 #endif
 402
 403 #define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
 404
 405 /*
 406  * Note: the _PAGE_COHERENT bit automatically gets set in the hardware
 407  * PTE if CONFIG_SMP is defined (hash_page does this); there is no need
 408  * to have it in the Linux PTE, and in fact the bit could be reused for
 409  * another purpose.  -- paulus.
 410  */
 411
 412 #ifdef CONFIG_44x
 413 #define _PAGE_BASE      (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_GUARDED)
 414 #else
 415 #define _PAGE_BASE      (_PAGE_PRESENT | _PAGE_ACCESSED)
 416 #endif
 417 #define _PAGE_WRENABLE  (_PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE)
 418 #define _PAGE_KERNEL    (_PAGE_BASE | _PAGE_SHARED | _PAGE_WRENABLE)
 419
 420 #ifdef CONFIG_PPC_STD_MMU
 421 /* On standard PPC MMU, no user access implies kernel read/write access,
 422  * so to write-protect kernel memory we must turn on user access */
 423 #define _PAGE_KERNEL_RO (_PAGE_BASE | _PAGE_SHARED | _PAGE_USER)
 424 #else
 425 #define _PAGE_KERNEL_RO (_PAGE_BASE | _PAGE_SHARED)
 426 #endif
 427
 428 #define _PAGE_IO        (_PAGE_KERNEL | _PAGE_NO_CACHE | _PAGE_GUARDED)
 429 #define _PAGE_RAM       (_PAGE_KERNEL | _PAGE_HWEXEC)
 430
 431 #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH)
 432 /* We want the debuggers to be able to set breakpoints anywhere, so
 433  * don't write protect the kernel text */
 434 #define _PAGE_RAM_TEXT  _PAGE_RAM
 435 #else
 436 #define _PAGE_RAM_TEXT  (_PAGE_KERNEL_RO | _PAGE_HWEXEC)
 437 #endif
 438
 439 #define PAGE_NONE       __pgprot(_PAGE_BASE)
 440 #define PAGE_READONLY   __pgprot(_PAGE_BASE | _PAGE_USER)
 441 #define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
 442 #define PAGE_SHARED     __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
 443 #define PAGE_SHARED_X   __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
 444 #define PAGE_COPY       __pgprot(_PAGE_BASE | _PAGE_USER)
 445 #define PAGE_COPY_X     __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
 446
 447 #define PAGE_KERNEL             __pgprot(_PAGE_RAM)
 448 #define PAGE_KERNEL_NOCACHE     __pgprot(_PAGE_IO)
 449
 450 /*
 451  * The PowerPC can only do execute protection on a segment (256MB) basis,
 452  * not on a page basis.  So we consider execute permission the same as read.
 453  * Also, write permissions imply read permissions.
 454  * This is the closest we can get..
 455  */
 456 #define __P000  PAGE_NONE
 457 #define __P001  PAGE_READONLY_X
 458 #define __P010  PAGE_COPY
 459 #define __P011  PAGE_COPY_X
 460 #define __P100  PAGE_READONLY
 461 #define __P101  PAGE_READONLY_X
 462 #define __P110  PAGE_COPY
 463 #define __P111  PAGE_COPY_X
 464
 465 #define __S000  PAGE_NONE
 466 #define __S001  PAGE_READONLY_X
 467 #define __S010  PAGE_SHARED
 468 #define __S011  PAGE_SHARED_X
 469 #define __S100  PAGE_READONLY
 470 #define __S101  PAGE_READONLY_X
 471 #define __S110  PAGE_SHARED
 472 #define __S111  PAGE_SHARED_X
 473
 474 #ifndef __ASSEMBLY__
 475 /* Make sure we get a link error if PMD_PAGE_SIZE is ever called on a
 476  * kernel without large page PMD support */
 477 extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
 478
 479 /*
 480  * Conversions between PTE values and page frame numbers.
 481  */
 482
 483 /* in some case we want to additionaly adjust where the pfn is in the pte to
 484  * allow room for more flags */
 485 #if defined(CONFIG_FSL_BOOKE) && defined(CONFIG_PTE_64BIT)
 486 #define PFN_SHIFT_OFFSET        (PAGE_SHIFT + 8)
 487 #else
 488 #define PFN_SHIFT_OFFSET        (PAGE_SHIFT)
 489 #endif
 490
 491 #define pte_pfn(x)              (pte_val(x) >> PFN_SHIFT_OFFSET)
 492 #define pte_page(x)             pfn_to_page(pte_pfn(x))
 493
 494 #define pfn_pte(pfn, prot)      __pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) |\
 495                                         pgprot_val(prot))
 496 #define mk_pte(page, prot)      pfn_pte(page_to_pfn(page), prot)
 497 #endif /* __ASSEMBLY__ */
 498
 499 #define pte_none(pte)           ((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
 500 #define pte_present(pte)        (pte_val(pte) & _PAGE_PRESENT)
 501 #define pte_clear(mm,addr,ptep) do { set_pte_at((mm), (addr), (ptep), __pte(0)); } while (0)
 502
 503 #define pmd_none(pmd)           (!pmd_val(pmd))
 504 #define pmd_bad(pmd)            (pmd_val(pmd) & _PMD_BAD)
 505 #define pmd_present(pmd)        (pmd_val(pmd) & _PMD_PRESENT_MASK)
 506 #define pmd_clear(pmdp)         do { pmd_val(*(pmdp)) = 0; } while (0)
 507
 508 #ifndef __ASSEMBLY__
 509 /*
 510  * The following only work if pte_present() is true.
 511  * Undefined behaviour if not..
 512  */
 513 static inline int pte_write(pte_t pte)          { return pte_val(pte) & _PAGE_RW; }
 514 static inline int pte_dirty(pte_t pte)          { return pte_val(pte) & _PAGE_DIRTY; }
 515 static inline int pte_young(pte_t pte)          { return pte_val(pte) & _PAGE_ACCESSED; }
 516 static inline int pte_file(pte_t pte)           { return pte_val(pte) & _PAGE_FILE; }
 517
 518 static inline void pte_uncache(pte_t pte)       { pte_val(pte) |= _PAGE_NO_CACHE; }
 519 static inline void pte_cache(pte_t pte)         { pte_val(pte) &= ~_PAGE_NO_CACHE; }
 520
 521 static inline pte_t pte_wrprotect(pte_t pte) {
 522         pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; }
 523 static inline pte_t pte_mkclean(pte_t pte) {
 524         pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; }
 525 static inline pte_t pte_mkold(pte_t pte) {
 526         pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
 527
 528 static inline pte_t pte_mkwrite(pte_t pte) {
 529         pte_val(pte) |= _PAGE_RW; return pte; }
 530 static inline pte_t pte_mkdirty(pte_t pte) {
 531         pte_val(pte) |= _PAGE_DIRTY; return pte; }
 532 static inline pte_t pte_mkyoung(pte_t pte) {
 533         pte_val(pte) |= _PAGE_ACCESSED; return pte; }
 534
 535 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 536 {
 537         pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
 538         return pte;
 539 }
 540
 541 /*
 542  * When flushing the tlb entry for a page, we also need to flush the hash
 543  * table entry.  flush_hash_pages is assembler (for speed) in hashtable.S.
 544  */
 545 extern int flush_hash_pages(unsigned context, unsigned long va,
 546                             unsigned long pmdval, int count);
 547
 548 /* Add an HPTE to the hash table */
 549 extern void add_hash_page(unsigned context, unsigned long va,
 550                           unsigned long pmdval);
 551
 552 /*
 553  * Atomic PTE updates.
 554  *
 555  * pte_update clears and sets bit atomically, and returns
 556  * the old pte value.  In the 64-bit PTE case we lock around the
 557  * low PTE word since we expect ALL flag bits to be there
 558  */
 559 #ifndef CONFIG_PTE_64BIT
 560 static inline unsigned long pte_update(pte_t *p, unsigned long clr,
 561                                        unsigned long set)
 562 {
 563         unsigned long old, tmp;
 564
 565         __asm__ __volatile__("\
 566 1:      lwarx   %0,0,%3\n\
 567         andc    %1,%0,%4\n\
 568         or      %1,%1,%5\n"
 569         PPC405_ERR77(0,%3)
 570 "       stwcx.  %1,0,%3\n\
 571         bne-    1b"
 572         : "=&r" (old), "=&r" (tmp), "=m" (*p)
 573         : "r" (p), "r" (clr), "r" (set), "m" (*p)
 574         : "cc" );
 575 #ifdef CONFIG_44x
 576         if ((old & _PAGE_USER) && (old & _PAGE_HWEXEC))
 577                 icache_44x_need_flush = 1;
 578 #endif
 579         return old;
 580 }
 581 #else
 582 static inline unsigned long long pte_update(pte_t *p, unsigned long clr,
 583                                        unsigned long set)
 584 {
 585         unsigned long long old;
 586         unsigned long tmp;
 587
 588         __asm__ __volatile__("\
 589 1:      lwarx   %L0,0,%4\n\
 590         lwzx    %0,0,%3\n\
 591         andc    %1,%L0,%5\n\
 592         or      %1,%1,%6\n"
 593         PPC405_ERR77(0,%3)
 594 "       stwcx.  %1,0,%4\n\
 595         bne-    1b"
 596         : "=&r" (old), "=&r" (tmp), "=m" (*p)
 597         : "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p)
 598         : "cc" );
 599 #ifdef CONFIG_44x
 600         if ((old & _PAGE_USER) && (old & _PAGE_HWEXEC))
 601                 icache_44x_need_flush = 1;
 602 #endif
 603         return old;
 604 }
 605 #endif
 606
 607 /*
 608  * set_pte stores a linux PTE into the linux page table.
 609  * On machines which use an MMU hash table we avoid changing the
 610  * _PAGE_HASHPTE bit.
 611  */
 612 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 613                               pte_t *ptep, pte_t pte)
 614 {
 615 #if _PAGE_HASHPTE != 0
 616         pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte) & ~_PAGE_HASHPTE);
 617 #else
 618         *ptep = pte;
 619 #endif
 620 }
 621
 622 /*
 623  * 2.6 calles this without flushing the TLB entry, this is wrong
 624  * for our hash-based implementation, we fix that up here
 625  */
 626 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 627 static inline int __ptep_test_and_clear_young(unsigned int context, unsigned long addr, pte_t *ptep)
 628 {
 629         unsigned long old;
 630         old = pte_update(ptep, _PAGE_ACCESSED, 0);
 631 #if _PAGE_HASHPTE != 0
 632         if (old & _PAGE_HASHPTE) {
 633                 unsigned long ptephys = __pa(ptep) & PAGE_MASK;
 634                 flush_hash_pages(context, addr, ptephys, 1);
 635         }
 636 #endif
 637         return (old & _PAGE_ACCESSED) != 0;
 638 }
 639 #define ptep_test_and_clear_young(__vma, __addr, __ptep) \
 640         __ptep_test_and_clear_young((__vma)->vm_mm->context.id, __addr, __ptep)
 641
 642 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 643 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 644                                        pte_t *ptep)
 645 {
 646         return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
 647 }
 648
 649 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 650 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 651                                       pte_t *ptep)
 652 {
 653         pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
 654 }
 655
 656 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
 657 static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
 658 {
 659         unsigned long bits = pte_val(entry) &
 660                 (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW);
 661         pte_update(ptep, 0, bits);
 662 }
 663
 664 #define  ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
 665 ({                                                                         \
 666         int __changed = !pte_same(*(__ptep), __entry);                     \
 667         if (__changed) {                                                   \
 668                 __ptep_set_access_flags(__ptep, __entry, __dirty);         \
 669                 flush_tlb_page_nohash(__vma, __address);                   \
 670         }                                                                  \
 671         __changed;                                                         \
 672 })
 673
 674 /*
 675  * Macro to mark a page protection value as "uncacheable".
 676  */
 677 #define pgprot_noncached(prot)  (__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
 678
 679 struct file;
 680 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 681                                      unsigned long size, pgprot_t vma_prot);
 682 #define __HAVE_PHYS_MEM_ACCESS_PROT
 683
 684 #define __HAVE_ARCH_PTE_SAME
 685 #define pte_same(A,B)   (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
 686
 687 /*
 688  * Note that on Book E processors, the pmd contains the kernel virtual
 689  * (lowmem) address of the pte page.  The physical address is less useful
 690  * because everything runs with translation enabled (even the TLB miss
 691  * handler).  On everything else the pmd contains the physical address
 692  * of the pte page.  -- paulus
 693  */
 694 #ifndef CONFIG_BOOKE
 695 #define pmd_page_vaddr(pmd)     \
 696         ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 697 #define pmd_page(pmd)           \
 698         (mem_map + (pmd_val(pmd) >> PAGE_SHIFT))
 699 #else
 700 #define pmd_page_vaddr(pmd)     \
 701         ((unsigned long) (pmd_val(pmd) & PAGE_MASK))
 702 #define pmd_page(pmd)           \
 703         (mem_map + (__pa(pmd_val(pmd)) >> PAGE_SHIFT))
 704 #endif
 705
 706 /* to find an entry in a kernel page-table-directory */
 707 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
 708
 709 /* to find an entry in a page-table-directory */
 710 #define pgd_index(address)       ((address) >> PGDIR_SHIFT)
 711 #define pgd_offset(mm, address)  ((mm)->pgd + pgd_index(address))
 712
 713 /* Find an entry in the third-level page table.. */
 714 #define pte_index(address)              \
 715         (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 716 #define pte_offset_kernel(dir, addr)    \
 717         ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
 718 #define pte_offset_map(dir, addr)               \
 719         ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE0) + pte_index(addr))
 720 #define pte_offset_map_nested(dir, addr)        \
 721         ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE1) + pte_index(addr))
 722
 723 #define pte_unmap(pte)          kunmap_atomic(pte, KM_PTE0)
 724 #define pte_unmap_nested(pte)   kunmap_atomic(pte, KM_PTE1)
 725
 726 /*
 727  * Encode and decode a swap entry.
 728  * Note that the bits we use in a PTE for representing a swap entry
 729  * must not include the _PAGE_PRESENT bit, the _PAGE_FILE bit, or the
 730  *_PAGE_HASHPTE bit (if used).  -- paulus
 731  */
 732 #define __swp_type(entry)               ((entry).val & 0x1f)
 733 #define __swp_offset(entry)             ((entry).val >> 5)
 734 #define __swp_entry(type, offset)       ((swp_entry_t) { (type) | ((offset) << 5) })
 735 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) >> 3 })
 736 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val << 3 })
 737
 738 /* Encode and decode a nonlinear file mapping entry */
 739 #define PTE_FILE_MAX_BITS       29
 740 #define pte_to_pgoff(pte)       (pte_val(pte) >> 3)
 741 #define pgoff_to_pte(off)       ((pte_t) { ((off) << 3) | _PAGE_FILE })
 742
 743 /*
 744  * No page table caches to initialise
 745  */
 746 #define pgtable_cache_init()    do { } while (0)
 747
 748 extern int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep,
 749                       pmd_t **pmdp);
 750
 751 #endif /* !__ASSEMBLY__ */
 752
 753 #endif /* _ASM_POWERPC_PGTABLE_PPC32_H */