arch/arm/include/asm/pgtable-3level.h

   1 /*
   2  * arch/arm/include/asm/pgtable-3level.h
   3  *
   4  * Copyright (C) 2011 ARM Ltd.
   5  * Author: Catalin Marinas <catalin.marinas@arm.com>
   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  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  */
  20 #ifndef _ASM_PGTABLE_3LEVEL_H
  21 #define _ASM_PGTABLE_3LEVEL_H
  22
  23 /*
  24  * With LPAE, there are 3 levels of page tables. Each level has 512 entries of
  25  * 8 bytes each, occupying a 4K page. The first level table covers a range of
  26  * 512GB, each entry representing 1GB. Since we are limited to 4GB input
  27  * address range, only 4 entries in the PGD are used.
  28  *
  29  * There are enough spare bits in a page table entry for the kernel specific
  30  * state.
  31  */
  32 #define PTRS_PER_PTE            512
  33 #define PTRS_PER_PMD            512
  34 #define PTRS_PER_PGD            4
  35
  36 #define PTE_HWTABLE_PTRS        (PTRS_PER_PTE)
  37 #define PTE_HWTABLE_OFF         (0)
  38 #define PTE_HWTABLE_SIZE        (PTRS_PER_PTE * sizeof(u64))
  39
  40 /*
  41  * PGDIR_SHIFT determines the size a top-level page table entry can map.
  42  */
  43 #define PGDIR_SHIFT             30
  44
  45 /*
  46  * PMD_SHIFT determines the size a middle-level page table entry can map.
  47  */
  48 #define PMD_SHIFT               21
  49
  50 #define PMD_SIZE                (1UL << PMD_SHIFT)
  51 #define PMD_MASK                (~(PMD_SIZE-1))
  52 #define PGDIR_SIZE              (1UL << PGDIR_SHIFT)
  53 #define PGDIR_MASK              (~(PGDIR_SIZE-1))
  54
  55 /*
  56  * section address mask and size definitions.
  57  */
  58 #define SECTION_SHIFT           21
  59 #define SECTION_SIZE            (1UL << SECTION_SHIFT)
  60 #define SECTION_MASK            (~(SECTION_SIZE-1))
  61
  62 #define USER_PTRS_PER_PGD       (PAGE_OFFSET / PGDIR_SIZE)
  63
  64 /*
  65  * "Linux" PTE definitions for LPAE.
  66  *
  67  * These bits overlap with the hardware bits but the naming is preserved for
  68  * consistency with the classic page table format.
  69  */
  70 #define L_PTE_PRESENT           (_AT(pteval_t, 3) << 0)         /* Valid */
  71 #define L_PTE_FILE              (_AT(pteval_t, 1) << 2)         /* only when !PRESENT */
  72 #define L_PTE_USER              (_AT(pteval_t, 1) << 6)         /* AP[1] */
  73 #define L_PTE_RDONLY            (_AT(pteval_t, 1) << 7)         /* AP[2] */
  74 #define L_PTE_SHARED            (_AT(pteval_t, 3) << 8)         /* SH[1:0], inner shareable */
  75 #define L_PTE_YOUNG             (_AT(pteval_t, 1) << 10)        /* AF */
  76 #define L_PTE_XN                (_AT(pteval_t, 1) << 54)        /* XN */
  77 #define L_PTE_DIRTY             (_AT(pteval_t, 1) << 55)        /* unused */
  78 #define L_PTE_SPECIAL           (_AT(pteval_t, 1) << 56)        /* unused */
  79
  80 /*
  81  * To be used in assembly code with the upper page attributes.
  82  */
  83 #define L_PTE_XN_HIGH           (1 << (54 - 32))
  84 #define L_PTE_DIRTY_HIGH        (1 << (55 - 32))
  85
  86 /*
  87  * AttrIndx[2:0] encoding (mapping attributes defined in the MAIR* registers).
  88  */
  89 #define L_PTE_MT_UNCACHED       (_AT(pteval_t, 0) << 2) /* strongly ordered */
  90 #define L_PTE_MT_BUFFERABLE     (_AT(pteval_t, 1) << 2) /* normal non-cacheable */
  91 #define L_PTE_MT_WRITETHROUGH   (_AT(pteval_t, 2) << 2) /* normal inner write-through */
  92 #define L_PTE_MT_WRITEBACK      (_AT(pteval_t, 3) << 2) /* normal inner write-back */
  93 #define L_PTE_MT_WRITEALLOC     (_AT(pteval_t, 7) << 2) /* normal inner write-alloc */
  94 #define L_PTE_MT_DEV_SHARED     (_AT(pteval_t, 4) << 2) /* device */
  95 #define L_PTE_MT_DEV_NONSHARED  (_AT(pteval_t, 4) << 2) /* device */
  96 #define L_PTE_MT_DEV_WC         (_AT(pteval_t, 1) << 2) /* normal non-cacheable */
  97 #define L_PTE_MT_DEV_CACHED     (_AT(pteval_t, 3) << 2) /* normal inner write-back */
  98 #define L_PTE_MT_MASK           (_AT(pteval_t, 7) << 2)
  99
 100 /*
 101  * Software PGD flags.
 102  */
 103 #define L_PGD_SWAPPER           (_AT(pgdval_t, 1) << 55)        /* swapper_pg_dir entry */
 104
 105 #ifndef __ASSEMBLY__
 106
 107 #define pud_none(pud)           (!pud_val(pud))
 108 #define pud_bad(pud)            (!(pud_val(pud) & 2))
 109 #define pud_present(pud)        (pud_val(pud))
 110
 111 #define pud_clear(pudp)                 \
 112         do {                            \
 113                 *pudp = __pud(0);       \
 114                 clean_pmd_entry(pudp);  \
 115         } while (0)
 116
 117 #define set_pud(pudp, pud)              \
 118         do {                            \
 119                 *pudp = pud;            \
 120                 flush_pmd_entry(pudp);  \
 121         } while (0)
 122
 123 static inline pmd_t *pud_page_vaddr(pud_t pud)
 124 {
 125         return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
 126 }
 127
 128 /* Find an entry in the second-level page table.. */
 129 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 130 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
 131 {
 132         return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
 133 }
 134
 135 #define pmd_bad(pmd)            (!(pmd_val(pmd) & 2))
 136
 137 #define copy_pmd(pmdpd,pmdps)           \
 138         do {                            \
 139                 *pmdpd = *pmdps;        \
 140                 flush_pmd_entry(pmdpd); \
 141         } while (0)
 142
 143 #define pmd_clear(pmdp)                 \
 144         do {                            \
 145                 *pmdp = __pmd(0);       \
 146                 clean_pmd_entry(pmdp);  \
 147         } while (0)
 148
 149 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,__pte(pte_val(pte)|(ext)))
 150
 151 #endif /* __ASSEMBLY__ */
 152
 153 #endif /* _ASM_PGTABLE_3LEVEL_H */