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 - SZ_32M - 1) 29 30 #define MODULES_VADDR (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M) 31 #define MODULES_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1) 32 33 struct mm_struct; 34 35 /* Helper macro */ 36 #define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED | \ 37 ((x) ? _PAGE_EXEC : 0) | \ 38 ((r) ? _PAGE_READ : 0) | \ 39 ((w) ? _PAGE_WRITE : 0)) 40 /* 41 * These are the macros that generic kernel code needs 42 * (to populate protection_map[]) 43 */ 44 45 /* Remove W bit on private pages for COW support */ 46 47 /* Shared pages can have exact HW mapping */ 48 49 /* Used all over the kernel */ 50 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 51 _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL) 52 53 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 54 _PAGE_WRITE | _PAGE_ACCESSED) 55 56 #define PAGE_COPY MKP(0, 0, 1) 57 58 #define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) 59 #define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) 60 61 #define USER_PTRS_PER_PGD \ 62 (CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE) 63 64 #define PGDIR_SHIFT 22 65 #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 66 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 67 68 /* 69 * ZERO_PAGE is a global shared page that is always zero: used 70 * for zero-mapped memory areas etc.. 71 */ 72 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 73 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) 74 75 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 76 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)]; 77 78 /* 79 * (pmds are folded into puds so this doesn't get actually called, 80 * but the define is needed for a generic inline function.) 81 */ 82 static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval) 83 { 84 *pmdptr = pmdval; 85 } 86 87 static inline int pte_write(pte_t pte) \ 88 { return pte_val(pte) & _PAGE_WRITE; } 89 static inline int pte_dirty(pte_t pte) \ 90 { return pte_val(pte) & _PAGE_DIRTY; } 91 static inline int pte_young(pte_t pte) \ 92 { return pte_val(pte) & _PAGE_ACCESSED; } 93 94 #define pgprot_noncached pgprot_noncached 95 96 static inline pgprot_t pgprot_noncached(pgprot_t _prot) 97 { 98 unsigned long prot = pgprot_val(_prot); 99 100 prot &= ~_PAGE_CACHED; 101 102 return __pgprot(prot); 103 } 104 105 static inline int pte_none(pte_t pte) 106 { 107 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf)); 108 } 109 110 static inline int pte_present(pte_t pte) \ 111 { return pte_val(pte) & _PAGE_PRESENT; } 112 113 /* 114 * The following only work if pte_present() is true. 115 * Undefined behaviour if not.. 116 */ 117 static inline pte_t pte_wrprotect(pte_t pte) 118 { 119 pte_val(pte) &= ~_PAGE_WRITE; 120 return pte; 121 } 122 123 static inline pte_t pte_mkclean(pte_t pte) 124 { 125 pte_val(pte) &= ~_PAGE_DIRTY; 126 return pte; 127 } 128 129 static inline pte_t pte_mkold(pte_t pte) 130 { 131 pte_val(pte) &= ~_PAGE_ACCESSED; 132 return pte; 133 } 134 135 static inline pte_t pte_mkwrite_novma(pte_t pte) 136 { 137 pte_val(pte) |= _PAGE_WRITE; 138 return pte; 139 } 140 141 static inline pte_t pte_mkdirty(pte_t pte) 142 { 143 pte_val(pte) |= _PAGE_DIRTY; 144 return pte; 145 } 146 147 static inline pte_t pte_mkyoung(pte_t pte) 148 { 149 pte_val(pte) |= _PAGE_ACCESSED; 150 return pte; 151 } 152 153 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 154 { 155 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC; 156 157 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 158 return pte; 159 } 160 161 static inline int pmd_present(pmd_t pmd) 162 { 163 return (pmd_val(pmd) != (unsigned long) invalid_pte_table) 164 && (pmd_val(pmd) != 0UL); 165 } 166 167 static inline void pmd_clear(pmd_t *pmdp) 168 { 169 pmd_val(*pmdp) = (unsigned long) invalid_pte_table; 170 } 171 172 #define pte_pfn(pte) (pte_val(pte) & 0xfffff) 173 #define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot))) 174 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 175 176 /* 177 * Store a linux PTE into the linux page table. 178 */ 179 static inline void set_pte(pte_t *ptep, pte_t pteval) 180 { 181 *ptep = pteval; 182 } 183 184 #define PFN_PTE_SHIFT 0 185 186 static inline void set_ptes(struct mm_struct *mm, unsigned long addr, 187 pte_t *ptep, pte_t pte, unsigned int nr) 188 { 189 unsigned long paddr = (unsigned long)page_to_virt(pte_page(pte)); 190 191 flush_dcache_range(paddr, paddr + nr * PAGE_SIZE); 192 for (;;) { 193 set_pte(ptep, pte); 194 if (--nr == 0) 195 break; 196 ptep++; 197 pte_val(pte) += 1; 198 } 199 } 200 #define set_ptes set_ptes 201 202 static inline int pmd_none(pmd_t pmd) 203 { 204 return (pmd_val(pmd) == 205 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL); 206 } 207 208 #define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) 209 210 static inline void pte_clear(struct mm_struct *mm, 211 unsigned long addr, pte_t *ptep) 212 { 213 pte_t null; 214 215 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf; 216 217 set_pte(ptep, null); 218 } 219 220 /* 221 * Conversion functions: convert a page and protection to a page entry, 222 * and a page entry and page directory to the page they refer to. 223 */ 224 #define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot)) 225 226 /* 227 * Conversion functions: convert a page and protection to a page entry, 228 * and a page entry and page directory to the page they refer to. 229 */ 230 #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd)) 231 #define pmd_pfn(pmd) (pmd_phys(pmd) >> PAGE_SHIFT) 232 #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT)) 233 234 static inline unsigned long pmd_page_vaddr(pmd_t pmd) 235 { 236 return pmd_val(pmd); 237 } 238 239 #define pte_ERROR(e) \ 240 pr_err("%s:%d: bad pte %08lx.\n", \ 241 __FILE__, __LINE__, pte_val(e)) 242 #define pgd_ERROR(e) \ 243 pr_err("%s:%d: bad pgd %08lx.\n", \ 244 __FILE__, __LINE__, pgd_val(e)) 245 246 /* 247 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that 248 * are !pte_none() && !pte_present(). 249 * 250 * Format of swap PTEs: 251 * 252 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 253 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 254 * E < type -> 0 0 0 0 0 0 <-------------- offset ---------------> 255 * 256 * E is the exclusive marker that is not stored in swap entries. 257 * 258 * Note that the offset field is always non-zero if the swap type is 0, thus 259 * !pte_none() is always true. 260 */ 261 #define __swp_type(swp) (((swp).val >> 26) & 0x1f) 262 #define __swp_offset(swp) ((swp).val & 0xfffff) 263 #define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x1f) << 26) \ 264 | ((off) & 0xfffff) }) 265 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 266 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 267 268 static inline int pte_swp_exclusive(pte_t pte) 269 { 270 return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; 271 } 272 273 static inline pte_t pte_swp_mkexclusive(pte_t pte) 274 { 275 pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; 276 return pte; 277 } 278 279 static inline pte_t pte_swp_clear_exclusive(pte_t pte) 280 { 281 pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; 282 return pte; 283 } 284 285 extern void __init paging_init(void); 286 extern void __init mmu_init(void); 287 288 void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma, 289 unsigned long address, pte_t *ptep, unsigned int nr); 290 291 #define update_mmu_cache(vma, addr, ptep) \ 292 update_mmu_cache_range(NULL, vma, addr, ptep, 1) 293 294 #endif /* _ASM_NIOS2_PGTABLE_H */ 295