1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
7 * Helpers for implemenintg paging levels
10 #ifndef _ASM_ARC_PGTABLE_LEVELS_H
11 #define _ASM_ARC_PGTABLE_LEVELS_H
13 #if CONFIG_PGTABLE_LEVELS == 2
16 * 2 level paging setup for software walked MMUv3 (ARC700) and MMUv4 (HS)
18 * [31] 32 bit virtual address [0]
19 * -------------------------------------------------------
20 * | | <---------- PGDIR_SHIFT ----------> |
21 * | | | <-- PAGE_SHIFT --> |
22 * -------------------------------------------------------
24 * | | --> off in page frame
25 * | ---> index into Page Table
26 * ----> index into Page Directory
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
33 #if defined(CONFIG_ARC_HUGEPAGE_16M)
34 #define PGDIR_SHIFT 24
35 #elif defined(CONFIG_ARC_HUGEPAGE_2M)
36 #define PGDIR_SHIFT 21
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)
44 #ifdef CONFIG_ARC_PAGE_SIZE_4K
45 #define PGDIR_SHIFT 22
47 #define PGDIR_SHIFT 21
52 #else /* CONFIG_PGTABLE_LEVELS != 2 */
55 * A default 3 level paging testing setup in software walked MMU
56 * MMUv4 (8K page): <4> : <7> : <8> : <13>
58 #define PGDIR_SHIFT 28
59 #if CONFIG_PGTABLE_LEVELS > 2
63 #endif /* CONFIG_PGTABLE_LEVELS */
65 #define PGDIR_SIZE BIT(PGDIR_SHIFT)
66 #define PGDIR_MASK (~(PGDIR_SIZE - 1))
67 #define PTRS_PER_PGD BIT(32 - PGDIR_SHIFT)
69 #if CONFIG_PGTABLE_LEVELS > 2
70 #define PMD_SIZE BIT(PMD_SHIFT)
71 #define PMD_MASK (~(PMD_SIZE - 1))
72 #define PTRS_PER_PMD BIT(PGDIR_SHIFT - PMD_SHIFT)
75 #define PTRS_PER_PTE BIT(PMD_SHIFT - PAGE_SHIFT)
79 #if CONFIG_PGTABLE_LEVELS > 2
80 #include <asm-generic/pgtable-nopud.h>
82 #include <asm-generic/pgtable-nopmd.h>
86 * 1st level paging: pgd
88 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
89 #define pgd_offset(mm, addr) (((mm)->pgd) + pgd_index(addr))
90 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
91 #define pgd_ERROR(e) \
92 pr_crit("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
94 #if CONFIG_PGTABLE_LEVELS > 2
96 /* In 3 level paging, pud_* macros work on pgd */
97 #define pud_none(x) (!pud_val(x))
98 #define pud_bad(x) ((pud_val(x) & ~PAGE_MASK))
99 #define pud_present(x) (pud_val(x))
100 #define pud_clear(xp) do { pud_val(*(xp)) = 0; } while (0)
101 #define pud_pgtable(pud) ((pmd_t *)(pud_val(pud) & PAGE_MASK))
102 #define pud_page(pud) virt_to_page(pud_pgtable(pud))
103 #define set_pud(pudp, pud) (*(pudp) = pud)
106 * 2nd level paging: pmd
108 #define pmd_ERROR(e) \
109 pr_crit("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
111 #define pmd_pfn(pmd) ((pmd_val(pmd) & PMD_MASK) >> PAGE_SHIFT)
112 #define pfn_pmd(pfn,prot) __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
113 #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
118 * Due to the strange way generic pgtable level folding works, the pmd_* macros
119 * - are valid even for 2 levels (which supposedly only has pgd - pte)
120 * - behave differently for 2 vs. 3
121 * In 2 level paging (pgd -> pte), pmd_* macros work on pgd
122 * In 3+ level paging (pgd -> pmd -> pte), pmd_* macros work on pmd
124 #define pmd_none(x) (!pmd_val(x))
125 #define pmd_bad(x) ((pmd_val(x) & ~PAGE_MASK))
126 #define pmd_present(x) (pmd_val(x))
127 #define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0)
128 #define pmd_page_vaddr(pmd) (pmd_val(pmd) & PAGE_MASK)
129 #define pmd_page(pmd) virt_to_page(pmd_page_vaddr(pmd))
130 #define set_pmd(pmdp, pmd) (*(pmdp) = pmd)
131 #define pmd_pgtable(pmd) ((pgtable_t) pmd_page_vaddr(pmd))
134 * 3rd level paging: pte
136 #define pte_ERROR(e) \
137 pr_crit("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
139 #define pte_none(x) (!pte_val(x))
140 #define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
141 #define pte_clear(mm,addr,ptep) set_pte_at(mm, addr, ptep, __pte(0))
142 #define pte_page(pte) pfn_to_page(pte_pfn(pte))
143 #define set_pte(ptep, pte) ((*(ptep)) = (pte))
144 #define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT)
145 #define pfn_pte(pfn, prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
146 #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot)
148 #ifdef CONFIG_ISA_ARCV2
149 #define pmd_leaf(x) (pmd_val(x) & _PAGE_HW_SZ)
152 #endif /* !__ASSEMBLY__ */