include/asm-sh/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 static __inline__ void pmd_set(pmd_t *pmdp,pte_t *ptep)
  47 {
  48         pmd_val(*pmdp) = (unsigned long) ptep;
  49 }
  50
  51 /*
  52  * PGD defines. Top level.
  53  */
  54
  55 /* To find an entry in a generic PGD. */
  56 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
  57 #define __pgd_offset(address) pgd_index(address)
  58 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
  59
  60 /* To find an entry in a kernel PGD. */
  61 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
  62
  63 /*
  64  * PMD level access routines. Same notes as above.
  65  */
  66 #define _PMD_EMPTY              0x0
  67 /* Either the PMD is empty or present, it's not paged out */
  68 #define pmd_present(pmd_entry)  (pmd_val(pmd_entry) & _PAGE_PRESENT)
  69 #define pmd_clear(pmd_entry_p)  (set_pmd((pmd_entry_p), __pmd(_PMD_EMPTY)))
  70 #define pmd_none(pmd_entry)     (pmd_val((pmd_entry)) == _PMD_EMPTY)
  71 #define pmd_bad(pmd_entry)      ((pmd_val(pmd_entry) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
  72
  73 #define pmd_page_vaddr(pmd_entry) \
  74         ((unsigned long) __va(pmd_val(pmd_entry) & PAGE_MASK))
  75
  76 #define pmd_page(pmd) \
  77         (virt_to_page(pmd_val(pmd)))
  78
  79 /* PMD to PTE dereferencing */
  80 #define pte_index(address) \
  81                 ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
  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  /* PR0-bit : read access allowed */
 120 #define _PAGE_EXECUTE   0x080  /* PR1-bit : execute access allowed */
 121 #define _PAGE_WRITE     0x100  /* PR2-bit : write access allowed */
 122 #define _PAGE_USER      0x200  /* PR3-bit : user space access allowed */
 123 #define _PAGE_DIRTY     0x400  /* software: page accessed in write */
 124 #define _PAGE_ACCESSED  0x800  /* software: page referenced */
 125
 126 /* Mask which drops software flags */
 127 #define _PAGE_FLAGS_HARDWARE_MASK       0xfffffffffffff3dbLL
 128
 129 /*
 130  * HugeTLB support
 131  */
 132 #if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
 133 #define _PAGE_SZHUGE    (_PAGE_SIZE0)
 134 #elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
 135 #define _PAGE_SZHUGE    (_PAGE_SIZE1)
 136 #elif defined(CONFIG_HUGETLB_PAGE_SIZE_512MB)
 137 #define _PAGE_SZHUGE    (_PAGE_SIZE0 | _PAGE_SIZE1)
 138 #endif
 139
 140 /*
 141  * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
 142  * to make pte_mkhuge() happy.
 143  */
 144 #ifndef _PAGE_SZHUGE
 145 # define _PAGE_SZHUGE   (0)
 146 #endif
 147
 148 /*
 149  * Default flags for a Kernel page.
 150  * This is fundametally also SHARED because the main use of this define
 151  * (other than for PGD/PMD entries) is for the VMALLOC pool which is
 152  * contextless.
 153  *
 154  * _PAGE_EXECUTE is required for modules
 155  *
 156  */
 157 #define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
 158                          _PAGE_EXECUTE | \
 159                          _PAGE_CACHABLE | _PAGE_ACCESSED | _PAGE_DIRTY | \
 160                          _PAGE_SHARED)
 161
 162 /* Default flags for a User page */
 163 #define _PAGE_TABLE     (_KERNPG_TABLE | _PAGE_USER)
 164
 165 #define _PAGE_CHG_MASK  (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
 166
 167 /*
 168  * We have full permissions (Read/Write/Execute/Shared).
 169  */
 170 #define _PAGE_COMMON    (_PAGE_PRESENT | _PAGE_USER | \
 171                          _PAGE_CACHABLE | _PAGE_ACCESSED)
 172
 173 #define PAGE_NONE       __pgprot(_PAGE_CACHABLE | _PAGE_ACCESSED)
 174 #define PAGE_SHARED     __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_WRITE | \
 175                                  _PAGE_SHARED)
 176 #define PAGE_EXECREAD   __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_EXECUTE)
 177
 178 /*
 179  * We need to include PAGE_EXECUTE in PAGE_COPY because it is the default
 180  * protection mode for the stack.
 181  */
 182 #define PAGE_COPY       PAGE_EXECREAD
 183
 184 #define PAGE_READONLY   __pgprot(_PAGE_COMMON | _PAGE_READ)
 185 #define PAGE_WRITEONLY  __pgprot(_PAGE_COMMON | _PAGE_WRITE)
 186 #define PAGE_RWX        __pgprot(_PAGE_COMMON | _PAGE_READ | \
 187                                  _PAGE_WRITE | _PAGE_EXECUTE)
 188 #define PAGE_KERNEL     __pgprot(_KERNPG_TABLE)
 189
 190 #define PAGE_KERNEL_NOCACHE \
 191                         __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
 192                                  _PAGE_EXECUTE | _PAGE_ACCESSED | \
 193                                  _PAGE_DIRTY | _PAGE_SHARED)
 194
 195 /* Make it a device mapping for maximum safety (e.g. for mapping device
 196    registers into user-space via /dev/map).  */
 197 #define pgprot_noncached(x) __pgprot(((x).pgprot & ~(_PAGE_CACHABLE)) | _PAGE_DEVICE)
 198 #define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
 199
 200 /*
 201  * Handling allocation failures during page table setup.
 202  */
 203 extern void __handle_bad_pmd_kernel(pmd_t * pmd);
 204 #define __handle_bad_pmd(x)     __handle_bad_pmd_kernel(x)
 205
 206 /*
 207  * PTE level access routines.
 208  *
 209  * Note1:
 210  * It's the tree walk leaf. This is physical address to be stored.
 211  *
 212  * Note 2:
 213  * Regarding the choice of _PTE_EMPTY:
 214
 215    We must choose a bit pattern that cannot be valid, whether or not the page
 216    is present.  bit[2]==1 => present, bit[2]==0 => swapped out.  If swapped
 217    out, bits [31:8], [6:3], [1:0] are under swapper control, so only bit[7] is
 218    left for us to select.  If we force bit[7]==0 when swapped out, we could use
 219    the combination bit[7,2]=2'b10 to indicate an empty PTE.  Alternatively, if
 220    we force bit[7]==1 when swapped out, we can use all zeroes to indicate
 221    empty.  This is convenient, because the page tables get cleared to zero
 222    when they are allocated.
 223
 224  */
 225 #define _PTE_EMPTY      0x0
 226 #define pte_present(x)  (pte_val(x) & _PAGE_PRESENT)
 227 #define pte_clear(mm,addr,xp)   (set_pte_at(mm, addr, xp, __pte(_PTE_EMPTY)))
 228 #define pte_none(x)     (pte_val(x) == _PTE_EMPTY)
 229
 230 /*
 231  * Some definitions to translate between mem_map, PTEs, and page
 232  * addresses:
 233  */
 234
 235 /*
 236  * Given a PTE, return the index of the mem_map[] entry corresponding
 237  * to the page frame the PTE. Get the absolute physical address, make
 238  * a relative physical address and translate it to an index.
 239  */
 240 #define pte_pagenr(x)           (((unsigned long) (pte_val(x)) - \
 241                                  __MEMORY_START) >> PAGE_SHIFT)
 242
 243 /*
 244  * Given a PTE, return the "struct page *".
 245  */
 246 #define pte_page(x)             (mem_map + pte_pagenr(x))
 247
 248 /*
 249  * Return number of (down rounded) MB corresponding to x pages.
 250  */
 251 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
 252
 253
 254 /*
 255  * The following have defined behavior only work if pte_present() is true.
 256  */
 257 static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_DIRTY; }
 258 static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 259 static inline int pte_file(pte_t pte)   { return pte_val(pte) & _PAGE_FILE; }
 260 static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 261 static inline int pte_special(pte_t pte){ return 0; }
 262
 263 static inline pte_t pte_wrprotect(pte_t pte)    { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_WRITE)); return pte; }
 264 static inline pte_t pte_mkclean(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); return pte; }
 265 static inline pte_t pte_mkold(pte_t pte)        { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); return pte; }
 266 static inline pte_t pte_mkwrite(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_WRITE)); return pte; }
 267 static inline pte_t pte_mkdirty(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
 268 static inline pte_t pte_mkyoung(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
 269 static inline pte_t pte_mkhuge(pte_t pte)       { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SZHUGE)); return pte; }
 270 static inline pte_t pte_mkspecial(pte_t pte)    { return pte; }
 271
 272
 273 /*
 274  * Conversion functions: convert a page and protection to a page entry.
 275  *
 276  * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
 277  */
 278 #define mk_pte(page,pgprot)                                                     \
 279 ({                                                                              \
 280         pte_t __pte;                                                            \
 281                                                                                 \
 282         set_pte(&__pte, __pte((((page)-mem_map) << PAGE_SHIFT) |                \
 283                 __MEMORY_START | pgprot_val((pgprot))));                        \
 284         __pte;                                                                  \
 285 })
 286
 287 /*
 288  * This takes a (absolute) physical page address that is used
 289  * by the remapping functions
 290  */
 291 #define mk_pte_phys(physpage, pgprot) \
 292 ({ pte_t __pte; set_pte(&__pte, __pte(physpage | pgprot_val(pgprot))); __pte; })
 293
 294 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 295 { set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot))); return pte; }
 296
 297 /* Encode and decode a swap entry */
 298 #define __swp_type(x)                   (((x).val & 3) + (((x).val >> 1) & 0x3c))
 299 #define __swp_offset(x)                 ((x).val >> 8)
 300 #define __swp_entry(type, offset)       ((swp_entry_t) { ((offset << 8) + ((type & 0x3c) << 1) + (type & 3)) })
 301 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 302 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 303
 304 /* Encode and decode a nonlinear file mapping entry */
 305 #define PTE_FILE_MAX_BITS               29
 306 #define pte_to_pgoff(pte)               (pte_val(pte))
 307 #define pgoff_to_pte(off)               ((pte_t) { (off) | _PAGE_FILE })
 308
 309 #endif /* !__ASSEMBLY__ */
 310
 311 #define pfn_pte(pfn, prot)      __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 312 #define pfn_pmd(pfn, prot)      __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 313
 314 #endif /* __ASM_SH_PGTABLE_64_H */