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