1 /* 2 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> 3 * Copyright (C) 2009 Wind River Systems Inc 4 * 5 * Based on asm/pgtable-32.h from mips which is: 6 * 7 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle 8 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc. 9 * 10 * This file is subject to the terms and conditions of the GNU General Public 11 * License. See the file "COPYING" in the main directory of this archive 12 * for more details. 13 */ 14 15 #ifndef _ASM_NIOS2_PGTABLE_H 16 #define _ASM_NIOS2_PGTABLE_H 17 18 #include <linux/io.h> 19 #include <linux/bug.h> 20 #include <asm/page.h> 21 #include <asm/cacheflush.h> 22 #include <asm/tlbflush.h> 23 24 #include <asm/pgtable-bits.h> 25 #include <asm-generic/pgtable-nopmd.h> 26 27 #define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE 28 #define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1) 29 30 struct mm_struct; 31 32 /* Helper macro */ 33 #define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED | \ 34 ((x) ? _PAGE_EXEC : 0) | \ 35 ((r) ? _PAGE_READ : 0) | \ 36 ((w) ? _PAGE_WRITE : 0)) 37 /* 38 * These are the macros that generic kernel code needs 39 * (to populate protection_map[]) 40 */ 41 42 /* Remove W bit on private pages for COW support */ 43 44 /* Shared pages can have exact HW mapping */ 45 46 /* Used all over the kernel */ 47 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 48 _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL) 49 50 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 51 _PAGE_WRITE | _PAGE_ACCESSED) 52 53 #define PAGE_COPY MKP(0, 0, 1) 54 55 #define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) 56 #define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) 57 58 #define USER_PTRS_PER_PGD \ 59 (CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE) 60 61 #define PGDIR_SHIFT 22 62 #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 63 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 64 65 /* 66 * ZERO_PAGE is a global shared page that is always zero: used 67 * for zero-mapped memory areas etc.. 68 */ 69 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 70 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) 71 72 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 73 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)]; 74 75 /* 76 * (pmds are folded into puds so this doesn't get actually called, 77 * but the define is needed for a generic inline function.) 78 */ 79 static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval) 80 { 81 *pmdptr = pmdval; 82 } 83 84 static inline int pte_write(pte_t pte) \ 85 { return pte_val(pte) & _PAGE_WRITE; } 86 static inline int pte_dirty(pte_t pte) \ 87 { return pte_val(pte) & _PAGE_DIRTY; } 88 static inline int pte_young(pte_t pte) \ 89 { return pte_val(pte) & _PAGE_ACCESSED; } 90 91 #define pgprot_noncached pgprot_noncached 92 93 static inline pgprot_t pgprot_noncached(pgprot_t _prot) 94 { 95 unsigned long prot = pgprot_val(_prot); 96 97 prot &= ~_PAGE_CACHED; 98 99 return __pgprot(prot); 100 } 101 102 static inline int pte_none(pte_t pte) 103 { 104 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf)); 105 } 106 107 static inline int pte_present(pte_t pte) \ 108 { return pte_val(pte) & _PAGE_PRESENT; } 109 110 /* 111 * The following only work if pte_present() is true. 112 * Undefined behaviour if not.. 113 */ 114 static inline pte_t pte_wrprotect(pte_t pte) 115 { 116 pte_val(pte) &= ~_PAGE_WRITE; 117 return pte; 118 } 119 120 static inline pte_t pte_mkclean(pte_t pte) 121 { 122 pte_val(pte) &= ~_PAGE_DIRTY; 123 return pte; 124 } 125 126 static inline pte_t pte_mkold(pte_t pte) 127 { 128 pte_val(pte) &= ~_PAGE_ACCESSED; 129 return pte; 130 } 131 132 static inline pte_t pte_mkwrite(pte_t pte) 133 { 134 pte_val(pte) |= _PAGE_WRITE; 135 return pte; 136 } 137 138 static inline pte_t pte_mkdirty(pte_t pte) 139 { 140 pte_val(pte) |= _PAGE_DIRTY; 141 return pte; 142 } 143 144 static inline pte_t pte_mkyoung(pte_t pte) 145 { 146 pte_val(pte) |= _PAGE_ACCESSED; 147 return pte; 148 } 149 150 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 151 { 152 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC; 153 154 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 155 return pte; 156 } 157 158 static inline int pmd_present(pmd_t pmd) 159 { 160 return (pmd_val(pmd) != (unsigned long) invalid_pte_table) 161 && (pmd_val(pmd) != 0UL); 162 } 163 164 static inline void pmd_clear(pmd_t *pmdp) 165 { 166 pmd_val(*pmdp) = (unsigned long) invalid_pte_table; 167 } 168 169 #define pte_pfn(pte) (pte_val(pte) & 0xfffff) 170 #define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot))) 171 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 172 173 /* 174 * Store a linux PTE into the linux page table. 175 */ 176 static inline void set_pte(pte_t *ptep, pte_t pteval) 177 { 178 *ptep = pteval; 179 } 180 181 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 182 pte_t *ptep, pte_t pteval) 183 { 184 unsigned long paddr = (unsigned long)page_to_virt(pte_page(pteval)); 185 186 flush_dcache_range(paddr, paddr + PAGE_SIZE); 187 set_pte(ptep, pteval); 188 } 189 190 static inline int pmd_none(pmd_t pmd) 191 { 192 return (pmd_val(pmd) == 193 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL); 194 } 195 196 #define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) 197 198 static inline void pte_clear(struct mm_struct *mm, 199 unsigned long addr, pte_t *ptep) 200 { 201 pte_t null; 202 203 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf; 204 205 set_pte_at(mm, addr, ptep, null); 206 } 207 208 /* 209 * Conversion functions: convert a page and protection to a page entry, 210 * and a page entry and page directory to the page they refer to. 211 */ 212 #define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot)) 213 214 /* 215 * Conversion functions: convert a page and protection to a page entry, 216 * and a page entry and page directory to the page they refer to. 217 */ 218 #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd)) 219 #define pmd_pfn(pmd) (pmd_phys(pmd) >> PAGE_SHIFT) 220 #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT)) 221 222 static inline unsigned long pmd_page_vaddr(pmd_t pmd) 223 { 224 return pmd_val(pmd); 225 } 226 227 #define pte_ERROR(e) \ 228 pr_err("%s:%d: bad pte %08lx.\n", \ 229 __FILE__, __LINE__, pte_val(e)) 230 #define pgd_ERROR(e) \ 231 pr_err("%s:%d: bad pgd %08lx.\n", \ 232 __FILE__, __LINE__, pgd_val(e)) 233 234 /* 235 * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte): 236 * 237 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ... 1 0 238 * 0 0 0 0 type. 0 0 0 0 0 0 offset......... 239 * 240 * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file. 241 * 242 * Note that the offset field is always non-zero, thus !pte_none(pte) is always 243 * true. 244 */ 245 #define __swp_type(swp) (((swp).val >> 26) & 0x3) 246 #define __swp_offset(swp) ((swp).val & 0xfffff) 247 #define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x3) << 26) \ 248 | ((off) & 0xfffff) }) 249 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 250 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 251 252 extern void __init paging_init(void); 253 extern void __init mmu_init(void); 254 255 extern void update_mmu_cache(struct vm_area_struct *vma, 256 unsigned long address, pte_t *pte); 257 258 #endif /* _ASM_NIOS2_PGTABLE_H */ 259