arch/arc/include/asm/pgtable-levels.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
   4  */
   5
   6 /*
   7  * Helpers for implemenintg paging levels
   8  */
   9
  10 #ifndef _ASM_ARC_PGTABLE_LEVELS_H
  11 #define _ASM_ARC_PGTABLE_LEVELS_H
  12
  13 #if CONFIG_PGTABLE_LEVELS == 2
  14
  15 /*
  16  * 2 level paging setup for software walked MMUv3 (ARC700) and MMUv4 (HS)
  17  *
  18  * [31]            32 bit virtual address              [0]
  19  * -------------------------------------------------------
  20  * |               | <---------- PGDIR_SHIFT ----------> |
  21  * |               |                | <-- PAGE_SHIFT --> |
  22  * -------------------------------------------------------
  23  *       |                  |                |
  24  *       |                  |                --> off in page frame
  25  *       |                  ---> index into Page Table
  26  *       ----> index into Page Directory
  27  *
  28  * Given software walk, the vaddr split is arbitrary set to 11:8:13
  29  * However enabling of super page in a 2 level regime pegs PGDIR_SHIFT to
  30  * super page size.
  31  */
  32
  33 #if defined(CONFIG_ARC_HUGEPAGE_16M)
  34 #define PGDIR_SHIFT             24
  35 #elif defined(CONFIG_ARC_HUGEPAGE_2M)
  36 #define PGDIR_SHIFT             21
  37 #else
  38 /*
  39  * No Super page case
  40  * Default value provides 11:8:13 (8K), 10:10:12 (4K)
  41  * Limits imposed by pgtable_t only PAGE_SIZE long
  42  * (so 4K page can only have 1K entries: or 10 bits)
  43  */
  44 #ifdef CONFIG_ARC_PAGE_SIZE_4K
  45 #define PGDIR_SHIFT             22
  46 #else
  47 #define PGDIR_SHIFT             21
  48 #endif
  49
  50 #endif
  51
  52 #else /* CONFIG_PGTABLE_LEVELS != 2 */
  53
  54 /*
  55  * A default 3 level paging testing setup in software walked MMU
  56  *   MMUv4 (8K page): <4> : <7> : <8> : <13>
  57  * A default 4 level paging testing setup in software walked MMU
  58  *   MMUv4 (8K page): <4> : <3> : <4> : <8> : <13>
  59  */
  60 #define PGDIR_SHIFT             28
  61 #if CONFIG_PGTABLE_LEVELS > 3
  62 #define PUD_SHIFT               25
  63 #endif
  64 #if CONFIG_PGTABLE_LEVELS > 2
  65 #define PMD_SHIFT               21
  66 #endif
  67
  68 #endif /* CONFIG_PGTABLE_LEVELS */
  69
  70 #define PGDIR_SIZE              BIT(PGDIR_SHIFT)
  71 #define PGDIR_MASK              (~(PGDIR_SIZE - 1))
  72 #define PTRS_PER_PGD            BIT(32 - PGDIR_SHIFT)
  73
  74 #if CONFIG_PGTABLE_LEVELS > 3
  75 #define PUD_SIZE                BIT(PUD_SHIFT)
  76 #define PUD_MASK                (~(PUD_SIZE - 1))
  77 #define PTRS_PER_PUD            BIT(PGDIR_SHIFT - PUD_SHIFT)
  78 #endif
  79
  80 #if CONFIG_PGTABLE_LEVELS > 2
  81 #define PMD_SIZE                BIT(PMD_SHIFT)
  82 #define PMD_MASK                (~(PMD_SIZE - 1))
  83 #define PTRS_PER_PMD            BIT(PUD_SHIFT - PMD_SHIFT)
  84 #endif
  85
  86 #define PTRS_PER_PTE            BIT(PMD_SHIFT - PAGE_SHIFT)
  87
  88 #ifndef __ASSEMBLY__
  89
  90 #if CONFIG_PGTABLE_LEVELS > 3
  91 #include <asm-generic/pgtable-nop4d.h>
  92 #elif CONFIG_PGTABLE_LEVELS > 2
  93 #include <asm-generic/pgtable-nopud.h>
  94 #else
  95 #include <asm-generic/pgtable-nopmd.h>
  96 #endif
  97
  98 /*
  99  * 1st level paging: pgd
 100  */
 101 #define pgd_ERROR(e) \
 102         pr_crit("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
 103
 104 #if CONFIG_PGTABLE_LEVELS > 3
 105
 106 /* In 4 level paging, p4d_* macros work on pgd */
 107 #define p4d_none(x)             (!p4d_val(x))
 108 #define p4d_bad(x)              ((p4d_val(x) & ~PAGE_MASK))
 109 #define p4d_present(x)          (p4d_val(x))
 110 #define p4d_clear(xp)           do { p4d_val(*(xp)) = 0; } while (0)
 111 #define p4d_pgtable(p4d)        ((pud_t *)(p4d_val(p4d) & PAGE_MASK))
 112 #define p4d_page(p4d)           virt_to_page(p4d_pgtable(p4d))
 113 #define set_p4d(p4dp, p4d)      (*(p4dp) = p4d)
 114
 115 /*
 116  * 2nd level paging: pud
 117  */
 118 #define pud_ERROR(e) \
 119         pr_crit("%s:%d: bad pud %08lx.\n", __FILE__, __LINE__, pud_val(e))
 120
 121 #endif
 122
 123 #if CONFIG_PGTABLE_LEVELS > 2
 124
 125 /*
 126  * In 3 level paging, pud_* macros work on pgd
 127  * In 4 level paging, pud_* macros work on pud
 128  */
 129 #define pud_none(x)             (!pud_val(x))
 130 #define pud_bad(x)              ((pud_val(x) & ~PAGE_MASK))
 131 #define pud_present(x)          (pud_val(x))
 132 #define pud_clear(xp)           do { pud_val(*(xp)) = 0; } while (0)
 133 #define pud_pgtable(pud)        ((pmd_t *)(pud_val(pud) & PAGE_MASK))
 134 #define pud_page(pud)           virt_to_page(pud_pgtable(pud))
 135 #define set_pud(pudp, pud)      (*(pudp) = pud)
 136
 137 /*
 138  * 3rd level paging: pmd
 139  */
 140 #define pmd_ERROR(e) \
 141         pr_crit("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
 142
 143 #define pmd_pfn(pmd)            ((pmd_val(pmd) & PMD_MASK) >> PAGE_SHIFT)
 144 #define pfn_pmd(pfn,prot)       __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 145 #define mk_pmd(page,prot)       pfn_pmd(page_to_pfn(page),prot)
 146
 147 #endif
 148
 149 /*
 150  * Due to the strange way generic pgtable level folding works, the pmd_* macros
 151  *  - are valid even for 2 levels (which supposedly only has pgd - pte)
 152  *  - behave differently for 2 vs. 3
 153  * In 2  level paging        (pgd -> pte), pmd_* macros work on pgd
 154  * In 3+ level paging (pgd -> pmd -> pte), pmd_* macros work on pmd
 155  */
 156 #define pmd_none(x)             (!pmd_val(x))
 157 #define pmd_bad(x)              ((pmd_val(x) & ~PAGE_MASK))
 158 #define pmd_present(x)          (pmd_val(x))
 159 #define pmd_clear(xp)           do { pmd_val(*(xp)) = 0; } while (0)
 160 #define pmd_page_vaddr(pmd)     (pmd_val(pmd) & PAGE_MASK)
 161 #define pmd_pfn(pmd)            ((pmd_val(pmd) & PAGE_MASK) >> PAGE_SHIFT)
 162 #define pmd_page(pmd)           virt_to_page((void *)pmd_page_vaddr(pmd))
 163 #define set_pmd(pmdp, pmd)      (*(pmdp) = pmd)
 164 #define pmd_pgtable(pmd)        ((pgtable_t) pmd_page(pmd))
 165
 166 /*
 167  * 4th level paging: pte
 168  */
 169 #define pte_ERROR(e) \
 170         pr_crit("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
 171
 172 #define PFN_PTE_SHIFT           PAGE_SHIFT
 173 #define pte_none(x)             (!pte_val(x))
 174 #define pte_present(x)          (pte_val(x) & _PAGE_PRESENT)
 175 #define pte_clear(mm,addr,ptep) set_pte_at(mm, addr, ptep, __pte(0))
 176 #define pte_page(pte)           pfn_to_page(pte_pfn(pte))
 177 #define set_pte(ptep, pte)      ((*(ptep)) = (pte))
 178 #define pte_pfn(pte)            (pte_val(pte) >> PAGE_SHIFT)
 179 #define pfn_pte(pfn, prot)      __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
 180 #define mk_pte(page, prot)      pfn_pte(page_to_pfn(page), prot)
 181
 182 #ifdef CONFIG_ISA_ARCV2
 183 #define pmd_leaf(x)             (pmd_val(x) & _PAGE_HW_SZ)
 184 #endif
 185
 186 #endif  /* !__ASSEMBLY__ */
 187
 188 #endif