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 FIRST_USER_ADDRESS 0 28 29 #define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE 30 #define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1) 31 32 struct mm_struct; 33 34 /* Helper macro */ 35 #define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED | \ 36 ((x) ? _PAGE_EXEC : 0) | \ 37 ((r) ? _PAGE_READ : 0) | \ 38 ((w) ? _PAGE_WRITE : 0)) 39 /* 40 * These are the macros that generic kernel code needs 41 * (to populate protection_map[]) 42 */ 43 44 /* Remove W bit on private pages for COW support */ 45 #define __P000 MKP(0, 0, 0) 46 #define __P001 MKP(0, 0, 1) 47 #define __P010 MKP(0, 0, 0) /* COW */ 48 #define __P011 MKP(0, 0, 1) /* COW */ 49 #define __P100 MKP(1, 0, 0) 50 #define __P101 MKP(1, 0, 1) 51 #define __P110 MKP(1, 0, 0) /* COW */ 52 #define __P111 MKP(1, 0, 1) /* COW */ 53 54 /* Shared pages can have exact HW mapping */ 55 #define __S000 MKP(0, 0, 0) 56 #define __S001 MKP(0, 0, 1) 57 #define __S010 MKP(0, 1, 0) 58 #define __S011 MKP(0, 1, 1) 59 #define __S100 MKP(1, 0, 0) 60 #define __S101 MKP(1, 0, 1) 61 #define __S110 MKP(1, 1, 0) 62 #define __S111 MKP(1, 1, 1) 63 64 /* Used all over the kernel */ 65 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 66 _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL) 67 68 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 69 _PAGE_WRITE | _PAGE_ACCESSED) 70 71 #define PAGE_COPY MKP(0, 0, 1) 72 73 #define PGD_ORDER 0 74 #define PTE_ORDER 0 75 76 #define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t)) 77 #define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t)) 78 79 #define USER_PTRS_PER_PGD \ 80 (CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE) 81 82 #define PGDIR_SHIFT 22 83 #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 84 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 85 86 /* 87 * ZERO_PAGE is a global shared page that is always zero: used 88 * for zero-mapped memory areas etc.. 89 */ 90 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 91 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) 92 93 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 94 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)]; 95 96 /* 97 * (pmds are folded into puds so this doesn't get actually called, 98 * but the define is needed for a generic inline function.) 99 */ 100 static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval) 101 { 102 pmdptr->pud.pgd.pgd = pmdval.pud.pgd.pgd; 103 } 104 105 /* to find an entry in a page-table-directory */ 106 #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)) 107 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr)) 108 109 static inline int pte_write(pte_t pte) \ 110 { return pte_val(pte) & _PAGE_WRITE; } 111 static inline int pte_dirty(pte_t pte) \ 112 { return pte_val(pte) & _PAGE_DIRTY; } 113 static inline int pte_young(pte_t pte) \ 114 { return pte_val(pte) & _PAGE_ACCESSED; } 115 static inline int pte_file(pte_t pte) \ 116 { return pte_val(pte) & _PAGE_FILE; } 117 static inline int pte_special(pte_t pte) { return 0; } 118 119 #define pgprot_noncached pgprot_noncached 120 121 static inline pgprot_t pgprot_noncached(pgprot_t _prot) 122 { 123 unsigned long prot = pgprot_val(_prot); 124 125 prot &= ~_PAGE_CACHED; 126 127 return __pgprot(prot); 128 } 129 130 static inline int pte_none(pte_t pte) 131 { 132 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf)); 133 } 134 135 static inline int pte_present(pte_t pte) \ 136 { return pte_val(pte) & _PAGE_PRESENT; } 137 138 /* 139 * The following only work if pte_present() is true. 140 * Undefined behaviour if not.. 141 */ 142 static inline pte_t pte_wrprotect(pte_t pte) 143 { 144 pte_val(pte) &= ~_PAGE_WRITE; 145 return pte; 146 } 147 148 static inline pte_t pte_mkclean(pte_t pte) 149 { 150 pte_val(pte) &= ~_PAGE_DIRTY; 151 return pte; 152 } 153 154 static inline pte_t pte_mkold(pte_t pte) 155 { 156 pte_val(pte) &= ~_PAGE_ACCESSED; 157 return pte; 158 } 159 160 static inline pte_t pte_mkwrite(pte_t pte) 161 { 162 pte_val(pte) |= _PAGE_WRITE; 163 return pte; 164 } 165 166 static inline pte_t pte_mkdirty(pte_t pte) 167 { 168 pte_val(pte) |= _PAGE_DIRTY; 169 return pte; 170 } 171 172 static inline pte_t pte_mkspecial(pte_t pte) { return pte; } 173 174 static inline pte_t pte_mkyoung(pte_t pte) 175 { 176 pte_val(pte) |= _PAGE_ACCESSED; 177 return pte; 178 } 179 180 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 181 { 182 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC; 183 184 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 185 return pte; 186 } 187 188 static inline int pmd_present(pmd_t pmd) 189 { 190 return (pmd_val(pmd) != (unsigned long) invalid_pte_table) 191 && (pmd_val(pmd) != 0UL); 192 } 193 194 static inline void pmd_clear(pmd_t *pmdp) 195 { 196 pmd_val(*pmdp) = (unsigned long) invalid_pte_table; 197 } 198 199 #define pte_pfn(pte) (pte_val(pte) & 0xfffff) 200 #define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot))) 201 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 202 203 /* 204 * Store a linux PTE into the linux page table. 205 */ 206 static inline void set_pte(pte_t *ptep, pte_t pteval) 207 { 208 *ptep = pteval; 209 } 210 211 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 212 pte_t *ptep, pte_t pteval) 213 { 214 unsigned long paddr = page_to_virt(pte_page(pteval)); 215 216 flush_dcache_range(paddr, paddr + PAGE_SIZE); 217 set_pte(ptep, pteval); 218 } 219 220 static inline int pmd_none(pmd_t pmd) 221 { 222 return (pmd_val(pmd) == 223 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL); 224 } 225 226 #define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) 227 228 static inline void pte_clear(struct mm_struct *mm, 229 unsigned long addr, pte_t *ptep) 230 { 231 pte_t null; 232 233 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf; 234 235 set_pte_at(mm, addr, ptep, null); 236 flush_tlb_one(addr); 237 } 238 239 /* 240 * Conversion functions: convert a page and protection to a page entry, 241 * and a page entry and page directory to the page they refer to. 242 */ 243 #define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot)) 244 245 #define pte_unmap(pte) do { } while (0) 246 247 /* 248 * Conversion functions: convert a page and protection to a page entry, 249 * and a page entry and page directory to the page they refer to. 250 */ 251 #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd)) 252 #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT)) 253 #define pmd_page_vaddr(pmd) pmd_val(pmd) 254 255 #define pte_offset_map(dir, addr) \ 256 ((pte_t *) page_address(pmd_page(*dir)) + \ 257 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))) 258 259 /* to find an entry in a kernel page-table-directory */ 260 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) 261 262 /* Get the address to the PTE for a vaddr in specific directory */ 263 #define pte_offset_kernel(dir, addr) \ 264 ((pte_t *) pmd_page_vaddr(*(dir)) + \ 265 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))) 266 267 #define pte_ERROR(e) \ 268 pr_err("%s:%d: bad pte %08lx.\n", \ 269 __FILE__, __LINE__, pte_val(e)) 270 #define pgd_ERROR(e) \ 271 pr_err("%s:%d: bad pgd %08lx.\n", \ 272 __FILE__, __LINE__, pgd_val(e)) 273 274 /* 275 * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte) 276 * && !pte_file(pte)): 277 * 278 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ... 1 0 279 * 0 0 0 0 type. 0 0 0 0 0 0 offset......... 280 * 281 * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file. 282 * 283 * Note that the offset field is always non-zero, thus !pte_none(pte) is always 284 * true. 285 */ 286 #define __swp_type(swp) (((swp).val >> 26) & 0x3) 287 #define __swp_offset(swp) ((swp).val & 0xfffff) 288 #define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x3) << 26) \ 289 | ((off) & 0xfffff) }) 290 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 291 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 292 293 /* Encode and decode a nonlinear file mapping entry */ 294 #define PTE_FILE_MAX_BITS 25 295 #define pte_to_pgoff(pte) (pte_val(pte) & 0x1ffffff) 296 #define pgoff_to_pte(off) __pte(((off) & 0x1ffffff) | _PAGE_FILE) 297 298 #define kern_addr_valid(addr) (1) 299 300 #include <asm-generic/pgtable.h> 301 302 #define pgtable_cache_init() do { } while (0) 303 304 extern void __init paging_init(void); 305 extern void __init mmu_init(void); 306 307 extern void update_mmu_cache(struct vm_area_struct *vma, 308 unsigned long address, pte_t *pte); 309 310 #endif /* _ASM_NIOS2_PGTABLE_H */ 311