release/src-rt-6.x.4708/linux/linux-2.6.36/arch/sh/include/asm/pgtable_64.h

   1 #ifndef __ASM_SH_PGTABLE_64_H
   2 #define __ASM_SH_PGTABLE_64_H
   3
   4 /*
   5  * include/asm-sh/pgtable_64.h
   6  *
   7  * This file contains the functions and defines necessary to modify and use
   8  * the SuperH page table tree.
   9  *
  10  * Copyright (C) 2000, 2001  Paolo Alberelli
  11  * Copyright (C) 2003, 2004  Paul Mundt
  12  * Copyright (C) 2003, 2004  Richard Curnow
  13  *
  14  * This file is subject to the terms and conditions of the GNU General Public
  15  * License.  See the file "COPYING" in the main directory of this archive
  16  * for more details.
  17  */
  18 #include <linux/threads.h>
  19 #include <asm/processor.h>
  20 #include <asm/page.h>
  21
  22 /*
  23  * Error outputs.
  24  */
  25 #define pte_ERROR(e) \
  26         printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e))
  27 #define pgd_ERROR(e) \
  28         printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
  29
  30 /*
  31  * Table setting routines. Used within arch/mm only.
  32  */
  33 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
  34
  35 static __inline__ void set_pte(pte_t *pteptr, pte_t pteval)
  36 {
  37         unsigned long long x = ((unsigned long long) pteval.pte_low);
  38         unsigned long long *xp = (unsigned long long *) pteptr;
  39         /*
  40          * Sign-extend based on NPHYS.
  41          */
  42         *(xp) = (x & NPHYS_SIGN) ? (x | NPHYS_MASK) : x;
  43 }
  44 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
  45
  46 /*
  47  * PGD defines. Top level.
  48  */
  49
  50 /* To find an entry in a generic PGD. */
  51 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
  52 #define __pgd_offset(address) pgd_index(address)
  53 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
  54
  55 /* To find an entry in a kernel PGD. */
  56 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
  57
  58 #define __pud_offset(address)   (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
  59 #define __pmd_offset(address)   (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
  60
  61 /*
  62  * PMD level access routines. Same notes as above.
  63  */
  64 #define _PMD_EMPTY              0x0
  65 /* Either the PMD is empty or present, it's not paged out */
  66 #define pmd_present(pmd_entry)  (pmd_val(pmd_entry) & _PAGE_PRESENT)
  67 #define pmd_clear(pmd_entry_p)  (set_pmd((pmd_entry_p), __pmd(_PMD_EMPTY)))
  68 #define pmd_none(pmd_entry)     (pmd_val((pmd_entry)) == _PMD_EMPTY)
  69 #define pmd_bad(pmd_entry)      ((pmd_val(pmd_entry) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
  70
  71 #define pmd_page_vaddr(pmd_entry) \
  72         ((unsigned long) __va(pmd_val(pmd_entry) & PAGE_MASK))
  73
  74 #define pmd_page(pmd) \
  75         (virt_to_page(pmd_val(pmd)))
  76
  77 /* PMD to PTE dereferencing */
  78 #define pte_index(address) \
  79                 ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
  80
  81 #define __pte_offset(address)   pte_index(address)
  82
  83 #define pte_offset_kernel(dir, addr) \
  84                 ((pte_t *) ((pmd_val(*(dir))) & PAGE_MASK) + pte_index((addr)))
  85
  86 #define pte_offset_map(dir,addr)        pte_offset_kernel(dir, addr)
  87 #define pte_offset_map_nested(dir,addr) pte_offset_kernel(dir, addr)
  88 #define pte_unmap(pte)          do { } while (0)
  89 #define pte_unmap_nested(pte)   do { } while (0)
  90
  91 #ifndef __ASSEMBLY__
  92 #define IOBASE_VADDR    0xff000000
  93 #define IOBASE_END      0xffffffff
  94
  95 /*
  96  * PTEL coherent flags.
  97  * See Chapter 17 ST50 CPU Core Volume 1, Architecture.
  98  */
  99 /* The bits that are required in the SH-5 TLB are placed in the h/w-defined
 100    positions, to avoid expensive bit shuffling on every refill.  The remaining
 101    bits are used for s/w purposes and masked out on each refill.
 102
 103    Note, the PTE slots are used to hold data of type swp_entry_t when a page is
 104    swapped out.  Only the _PAGE_PRESENT flag is significant when the page is
 105    swapped out, and it must be placed so that it doesn't overlap either the
 106    type or offset fields of swp_entry_t.  For x86, offset is at [31:8] and type
 107    at [6:1], with _PAGE_PRESENT at bit 0 for both pte_t and swp_entry_t.  This
 108    scheme doesn't map to SH-5 because bit [0] controls cacheability.  So bit
 109    [2] is used for _PAGE_PRESENT and the type field of swp_entry_t is split
 110    into 2 pieces.  That is handled by SWP_ENTRY and SWP_TYPE below. */
 111 #define _PAGE_WT        0x001  /* CB0: if cacheable, 1->write-thru, 0->write-back */
 112 #define _PAGE_DEVICE    0x001  /* CB0: if uncacheable, 1->device (i.e. no write-combining or reordering at bus level) */
 113 #define _PAGE_CACHABLE  0x002  /* CB1: uncachable/cachable */
 114 #define _PAGE_PRESENT   0x004  /* software: page referenced */
 115 #define _PAGE_FILE      0x004  /* software: only when !present */
 116 #define _PAGE_SIZE0     0x008  /* SZ0-bit : size of page */
 117 #define _PAGE_SIZE1     0x010  /* SZ1-bit : size of page */
 118 #define _PAGE_SHARED    0x020  /* software: reflects PTEH's SH */
 119 #define _PAGE_READ      0x040
 120 #define _PAGE_EXECUTE   0x080
 121 #define _PAGE_WRITE     0x100
 122 #define _PAGE_USER      0x200
 123 #define _PAGE_DIRTY     0x400  /* software: page accessed in write */
 124 #define _PAGE_ACCESSED  0x800  /* software: page referenced */
 125
 126 /* Wrapper for extended mode pgprot twiddling */
 127 #define _PAGE_EXT(x)            ((unsigned long long)(x) << 32)
 128
 129 /*
 130  * We can use the sign-extended bits in the PTEL to get 32 bits of
 131  * software flags. This works for now because no implementations uses
 132  * anything above the PPN field.
 133  */
 134 #define _PAGE_WIRED     _PAGE_EXT(0x001) /* software: wire the tlb entry */
 135
 136 #define _PAGE_CLEAR_FLAGS       (_PAGE_PRESENT | _PAGE_FILE | _PAGE_SHARED | \
 137                                  _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_WIRED)
 138
 139 /* Mask which drops software flags */
 140 #define _PAGE_FLAGS_HARDWARE_MASK       (NEFF_MASK & ~(_PAGE_CLEAR_FLAGS))
 141
 142 /*
 143  * HugeTLB support
 144  */
 145 #if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
 146 #define _PAGE_SZHUGE    (_PAGE_SIZE0)
 147 #elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
 148 #define _PAGE_SZHUGE    (_PAGE_SIZE1)
 149 #elif defined(CONFIG_HUGETLB_PAGE_SIZE_512MB)
 150 #define _PAGE_SZHUGE    (_PAGE_SIZE0 | _PAGE_SIZE1)
 151 #endif
 152
 153 /*
 154  * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
 155  * to make pte_mkhuge() happy.
 156  */
 157 #ifndef _PAGE_SZHUGE
 158 # define _PAGE_SZHUGE   (0)
 159 #endif
 160
 161 /*
 162  * Default flags for a Kernel page.
 163  * This is fundametally also SHARED because the main use of this define
 164  * (other than for PGD/PMD entries) is for the VMALLOC pool which is
 165  * contextless.
 166  *
 167  * _PAGE_EXECUTE is required for modules
 168  *
 169  */
 170 #define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
 171                          _PAGE_EXECUTE | \
 172                          _PAGE_CACHABLE | _PAGE_ACCESSED | _PAGE_DIRTY | \
 173                          _PAGE_SHARED)
 174
 175 /* Default flags for a User page */
 176 #define _PAGE_TABLE     (_KERNPG_TABLE | _PAGE_USER)
 177
 178 #define _PAGE_CHG_MASK  (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
 179
 180 /*
 181  * We have full permissions (Read/Write/Execute/Shared).
 182  */
 183 #define _PAGE_COMMON    (_PAGE_PRESENT | _PAGE_USER | \
 184                          _PAGE_CACHABLE | _PAGE_ACCESSED)
 185
 186 #define PAGE_NONE       __pgprot(_PAGE_CACHABLE | _PAGE_ACCESSED)
 187 #define PAGE_SHARED     __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_WRITE | \
 188                                  _PAGE_SHARED)
 189 #define PAGE_EXECREAD   __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_EXECUTE)
 190
 191 /*
 192  * We need to include PAGE_EXECUTE in PAGE_COPY because it is the default
 193  * protection mode for the stack.
 194  */
 195 #define PAGE_COPY       PAGE_EXECREAD
 196
 197 #define PAGE_READONLY   __pgprot(_PAGE_COMMON | _PAGE_READ)
 198 #define PAGE_WRITEONLY  __pgprot(_PAGE_COMMON | _PAGE_WRITE)
 199 #define PAGE_RWX        __pgprot(_PAGE_COMMON | _PAGE_READ | \
 200                                  _PAGE_WRITE | _PAGE_EXECUTE)
 201 #define PAGE_KERNEL     __pgprot(_KERNPG_TABLE)
 202
 203 #define PAGE_KERNEL_NOCACHE \
 204                         __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
 205                                  _PAGE_EXECUTE | _PAGE_ACCESSED | \
 206                                  _PAGE_DIRTY | _PAGE_SHARED)
 207
 208 /* Make it a device mapping for maximum safety (e.g. for mapping device
 209    registers into user-space via /dev/map).  */
 210 #define pgprot_noncached(x) __pgprot(((x).pgprot & ~(_PAGE_CACHABLE)) | _PAGE_DEVICE)
 211 #define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
 212
 213 /*
 214  * PTE level access routines.
 215  *
 216  * Note1:
 217  * It's the tree walk leaf. This is physical address to be stored.
 218  *
 219  * Note 2:
 220  * Regarding the choice of _PTE_EMPTY:
 221
 222    We must choose a bit pattern that cannot be valid, whether or not the page
 223    is present.  bit[2]==1 => present, bit[2]==0 => swapped out.  If swapped
 224    out, bits [31:8], [6:3], [1:0] are under swapper control, so only bit[7] is
 225    left for us to select.  If we force bit[7]==0 when swapped out, we could use
 226    the combination bit[7,2]=2'b10 to indicate an empty PTE.  Alternatively, if
 227    we force bit[7]==1 when swapped out, we can use all zeroes to indicate
 228    empty.  This is convenient, because the page tables get cleared to zero
 229    when they are allocated.
 230
 231  */
 232 #define _PTE_EMPTY      0x0
 233 #define pte_present(x)  (pte_val(x) & _PAGE_PRESENT)
 234 #define pte_clear(mm,addr,xp)   (set_pte_at(mm, addr, xp, __pte(_PTE_EMPTY)))
 235 #define pte_none(x)     (pte_val(x) == _PTE_EMPTY)
 236
 237 /*
 238  * Some definitions to translate between mem_map, PTEs, and page
 239  * addresses:
 240  */
 241
 242 /*
 243  * Given a PTE, return the index of the mem_map[] entry corresponding
 244  * to the page frame the PTE. Get the absolute physical address, make
 245  * a relative physical address and translate it to an index.
 246  */
 247 #define pte_pagenr(x)           (((unsigned long) (pte_val(x)) - \
 248                                  __MEMORY_START) >> PAGE_SHIFT)
 249
 250 /*
 251  * Given a PTE, return the "struct page *".
 252  */
 253 #define pte_page(x)             (mem_map + pte_pagenr(x))
 254
 255 /*
 256  * Return number of (down rounded) MB corresponding to x pages.
 257  */
 258 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
 259
 260
 261 /*
 262  * The following have defined behavior only work if pte_present() is true.
 263  */
 264 static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_DIRTY; }
 265 static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 266 static inline int pte_file(pte_t pte)   { return pte_val(pte) & _PAGE_FILE; }
 267 static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 268 static inline int pte_special(pte_t pte){ return 0; }
 269
 270 static inline pte_t pte_wrprotect(pte_t pte)    { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_WRITE)); return pte; }
 271 static inline pte_t pte_mkclean(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); return pte; }
 272 static inline pte_t pte_mkold(pte_t pte)        { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); return pte; }
 273 static inline pte_t pte_mkwrite(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_WRITE)); return pte; }
 274 static inline pte_t pte_mkdirty(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
 275 static inline pte_t pte_mkyoung(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
 276 static inline pte_t pte_mkhuge(pte_t pte)       { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SZHUGE)); return pte; }
 277 static inline pte_t pte_mkspecial(pte_t pte)    { return pte; }
 278
 279
 280 /*
 281  * Conversion functions: convert a page and protection to a page entry.
 282  *
 283  * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
 284  */
 285 #define mk_pte(page,pgprot)                                                     \
 286 ({                                                                              \
 287         pte_t __pte;                                                            \
 288                                                                                 \
 289         set_pte(&__pte, __pte((((page)-mem_map) << PAGE_SHIFT) |                \
 290                 __MEMORY_START | pgprot_val((pgprot))));                        \
 291         __pte;                                                                  \
 292 })
 293
 294 /*
 295  * This takes a (absolute) physical page address that is used
 296  * by the remapping functions
 297  */
 298 #define mk_pte_phys(physpage, pgprot) \
 299 ({ pte_t __pte; set_pte(&__pte, __pte(physpage | pgprot_val(pgprot))); __pte; })
 300
 301 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 302 { set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot))); return pte; }
 303
 304 /* Encode and decode a swap entry */
 305 #define __swp_type(x)                   (((x).val & 3) + (((x).val >> 1) & 0x3c))
 306 #define __swp_offset(x)                 ((x).val >> 8)
 307 #define __swp_entry(type, offset)       ((swp_entry_t) { ((offset << 8) + ((type & 0x3c) << 1) + (type & 3)) })
 308 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 309 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 310
 311 /* Encode and decode a nonlinear file mapping entry */
 312 #define PTE_FILE_MAX_BITS               29
 313 #define pte_to_pgoff(pte)               (pte_val(pte))
 314 #define pgoff_to_pte(off)               ((pte_t) { (off) | _PAGE_FILE })
 315
 316 #endif /* !__ASSEMBLY__ */
 317
 318 #define pfn_pte(pfn, prot)      __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 319 #define pfn_pmd(pfn, prot)      __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 320
 321 #endif /* __ASM_SH_PGTABLE_64_H */