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 #define __ARCH_USE_5LEVEL_HACK 26 #include <asm-generic/pgtable-nopmd.h> 27 28 #define FIRST_USER_ADDRESS 0UL 29 30 #define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE 31 #define VMALLOC_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 #define __P000 MKP(0, 0, 0) 47 #define __P001 MKP(0, 0, 1) 48 #define __P010 MKP(0, 0, 0) /* COW */ 49 #define __P011 MKP(0, 0, 1) /* COW */ 50 #define __P100 MKP(1, 0, 0) 51 #define __P101 MKP(1, 0, 1) 52 #define __P110 MKP(1, 0, 0) /* COW */ 53 #define __P111 MKP(1, 0, 1) /* COW */ 54 55 /* Shared pages can have exact HW mapping */ 56 #define __S000 MKP(0, 0, 0) 57 #define __S001 MKP(0, 0, 1) 58 #define __S010 MKP(0, 1, 0) 59 #define __S011 MKP(0, 1, 1) 60 #define __S100 MKP(1, 0, 0) 61 #define __S101 MKP(1, 0, 1) 62 #define __S110 MKP(1, 1, 0) 63 #define __S111 MKP(1, 1, 1) 64 65 /* Used all over the kernel */ 66 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 67 _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL) 68 69 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \ 70 _PAGE_WRITE | _PAGE_ACCESSED) 71 72 #define PAGE_COPY MKP(0, 0, 1) 73 74 #define PGD_ORDER 0 75 #define PTE_ORDER 0 76 77 #define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t)) 78 #define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t)) 79 80 #define USER_PTRS_PER_PGD \ 81 (CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE) 82 83 #define PGDIR_SHIFT 22 84 #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 85 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 86 87 /* 88 * ZERO_PAGE is a global shared page that is always zero: used 89 * for zero-mapped memory areas etc.. 90 */ 91 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 92 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) 93 94 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 95 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)]; 96 97 /* 98 * (pmds are folded into puds so this doesn't get actually called, 99 * but the define is needed for a generic inline function.) 100 */ 101 static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval) 102 { 103 pmdptr->pud.pgd.pgd = pmdval.pud.pgd.pgd; 104 } 105 106 /* to find an entry in a page-table-directory */ 107 #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)) 108 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr)) 109 110 static inline int pte_write(pte_t pte) \ 111 { return pte_val(pte) & _PAGE_WRITE; } 112 static inline int pte_dirty(pte_t pte) \ 113 { return pte_val(pte) & _PAGE_DIRTY; } 114 static inline int pte_young(pte_t pte) \ 115 { return pte_val(pte) & _PAGE_ACCESSED; } 116 static inline int pte_special(pte_t pte) { return 0; } 117 118 #define pgprot_noncached pgprot_noncached 119 120 static inline pgprot_t pgprot_noncached(pgprot_t _prot) 121 { 122 unsigned long prot = pgprot_val(_prot); 123 124 prot &= ~_PAGE_CACHED; 125 126 return __pgprot(prot); 127 } 128 129 static inline int pte_none(pte_t pte) 130 { 131 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf)); 132 } 133 134 static inline int pte_present(pte_t pte) \ 135 { return pte_val(pte) & _PAGE_PRESENT; } 136 137 /* 138 * The following only work if pte_present() is true. 139 * Undefined behaviour if not.. 140 */ 141 static inline pte_t pte_wrprotect(pte_t pte) 142 { 143 pte_val(pte) &= ~_PAGE_WRITE; 144 return pte; 145 } 146 147 static inline pte_t pte_mkclean(pte_t pte) 148 { 149 pte_val(pte) &= ~_PAGE_DIRTY; 150 return pte; 151 } 152 153 static inline pte_t pte_mkold(pte_t pte) 154 { 155 pte_val(pte) &= ~_PAGE_ACCESSED; 156 return pte; 157 } 158 159 static inline pte_t pte_mkwrite(pte_t pte) 160 { 161 pte_val(pte) |= _PAGE_WRITE; 162 return pte; 163 } 164 165 static inline pte_t pte_mkdirty(pte_t pte) 166 { 167 pte_val(pte) |= _PAGE_DIRTY; 168 return pte; 169 } 170 171 static inline pte_t pte_mkspecial(pte_t pte) { return pte; } 172 173 static inline pte_t pte_mkyoung(pte_t pte) 174 { 175 pte_val(pte) |= _PAGE_ACCESSED; 176 return pte; 177 } 178 179 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 180 { 181 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC; 182 183 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 184 return pte; 185 } 186 187 static inline int pmd_present(pmd_t pmd) 188 { 189 return (pmd_val(pmd) != (unsigned long) invalid_pte_table) 190 && (pmd_val(pmd) != 0UL); 191 } 192 193 static inline void pmd_clear(pmd_t *pmdp) 194 { 195 pmd_val(*pmdp) = (unsigned long) invalid_pte_table; 196 } 197 198 #define pte_pfn(pte) (pte_val(pte) & 0xfffff) 199 #define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot))) 200 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 201 202 /* 203 * Store a linux PTE into the linux page table. 204 */ 205 static inline void set_pte(pte_t *ptep, pte_t pteval) 206 { 207 *ptep = pteval; 208 } 209 210 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 211 pte_t *ptep, pte_t pteval) 212 { 213 unsigned long paddr = (unsigned long)page_to_virt(pte_page(pteval)); 214 215 flush_dcache_range(paddr, paddr + PAGE_SIZE); 216 set_pte(ptep, pteval); 217 } 218 219 static inline int pmd_none(pmd_t pmd) 220 { 221 return (pmd_val(pmd) == 222 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL); 223 } 224 225 #define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) 226 227 static inline void pte_clear(struct mm_struct *mm, 228 unsigned long addr, pte_t *ptep) 229 { 230 pte_t null; 231 232 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf; 233 234 set_pte_at(mm, addr, ptep, null); 235 } 236 237 /* 238 * Conversion functions: convert a page and protection to a page entry, 239 * and a page entry and page directory to the page they refer to. 240 */ 241 #define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot)) 242 243 #define pte_unmap(pte) do { } while (0) 244 245 /* 246 * Conversion functions: convert a page and protection to a page entry, 247 * and a page entry and page directory to the page they refer to. 248 */ 249 #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd)) 250 #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT)) 251 #define pmd_page_vaddr(pmd) pmd_val(pmd) 252 253 #define pte_offset_map(dir, addr) \ 254 ((pte_t *) page_address(pmd_page(*dir)) + \ 255 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))) 256 257 /* to find an entry in a kernel page-table-directory */ 258 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) 259 260 /* Get the address to the PTE for a vaddr in specific directory */ 261 #define pte_offset_kernel(dir, addr) \ 262 ((pte_t *) pmd_page_vaddr(*(dir)) + \ 263 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))) 264 265 #define pte_ERROR(e) \ 266 pr_err("%s:%d: bad pte %08lx.\n", \ 267 __FILE__, __LINE__, pte_val(e)) 268 #define pgd_ERROR(e) \ 269 pr_err("%s:%d: bad pgd %08lx.\n", \ 270 __FILE__, __LINE__, pgd_val(e)) 271 272 /* 273 * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte): 274 * 275 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ... 1 0 276 * 0 0 0 0 type. 0 0 0 0 0 0 offset......... 277 * 278 * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file. 279 * 280 * Note that the offset field is always non-zero, thus !pte_none(pte) is always 281 * true. 282 */ 283 #define __swp_type(swp) (((swp).val >> 26) & 0x3) 284 #define __swp_offset(swp) ((swp).val & 0xfffff) 285 #define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x3) << 26) \ 286 | ((off) & 0xfffff) }) 287 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 288 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 289 290 #define kern_addr_valid(addr) (1) 291 292 #include <asm-generic/pgtable.h> 293 294 #define pgtable_cache_init() do { } while (0) 295 296 extern void __init paging_init(void); 297 extern void __init mmu_init(void); 298 299 extern void update_mmu_cache(struct vm_area_struct *vma, 300 unsigned long address, pte_t *pte); 301 302 #endif /* _ASM_NIOS2_PGTABLE_H */ 303