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 0UL 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 = pmdval; 103 } 104 105 static inline int pte_write(pte_t pte) \ 106 { return pte_val(pte) & _PAGE_WRITE; } 107 static inline int pte_dirty(pte_t pte) \ 108 { return pte_val(pte) & _PAGE_DIRTY; } 109 static inline int pte_young(pte_t pte) \ 110 { return pte_val(pte) & _PAGE_ACCESSED; } 111 112 #define pgprot_noncached pgprot_noncached 113 114 static inline pgprot_t pgprot_noncached(pgprot_t _prot) 115 { 116 unsigned long prot = pgprot_val(_prot); 117 118 prot &= ~_PAGE_CACHED; 119 120 return __pgprot(prot); 121 } 122 123 static inline int pte_none(pte_t pte) 124 { 125 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf)); 126 } 127 128 static inline int pte_present(pte_t pte) \ 129 { return pte_val(pte) & _PAGE_PRESENT; } 130 131 /* 132 * The following only work if pte_present() is true. 133 * Undefined behaviour if not.. 134 */ 135 static inline pte_t pte_wrprotect(pte_t pte) 136 { 137 pte_val(pte) &= ~_PAGE_WRITE; 138 return pte; 139 } 140 141 static inline pte_t pte_mkclean(pte_t pte) 142 { 143 pte_val(pte) &= ~_PAGE_DIRTY; 144 return pte; 145 } 146 147 static inline pte_t pte_mkold(pte_t pte) 148 { 149 pte_val(pte) &= ~_PAGE_ACCESSED; 150 return pte; 151 } 152 153 static inline pte_t pte_mkwrite(pte_t pte) 154 { 155 pte_val(pte) |= _PAGE_WRITE; 156 return pte; 157 } 158 159 static inline pte_t pte_mkdirty(pte_t pte) 160 { 161 pte_val(pte) |= _PAGE_DIRTY; 162 return pte; 163 } 164 165 static inline pte_t pte_mkyoung(pte_t pte) 166 { 167 pte_val(pte) |= _PAGE_ACCESSED; 168 return pte; 169 } 170 171 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 172 { 173 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC; 174 175 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 176 return pte; 177 } 178 179 static inline int pmd_present(pmd_t pmd) 180 { 181 return (pmd_val(pmd) != (unsigned long) invalid_pte_table) 182 && (pmd_val(pmd) != 0UL); 183 } 184 185 static inline void pmd_clear(pmd_t *pmdp) 186 { 187 pmd_val(*pmdp) = (unsigned long) invalid_pte_table; 188 } 189 190 #define pte_pfn(pte) (pte_val(pte) & 0xfffff) 191 #define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot))) 192 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 193 194 /* 195 * Store a linux PTE into the linux page table. 196 */ 197 static inline void set_pte(pte_t *ptep, pte_t pteval) 198 { 199 *ptep = pteval; 200 } 201 202 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 203 pte_t *ptep, pte_t pteval) 204 { 205 unsigned long paddr = (unsigned long)page_to_virt(pte_page(pteval)); 206 207 flush_dcache_range(paddr, paddr + PAGE_SIZE); 208 set_pte(ptep, pteval); 209 } 210 211 static inline int pmd_none(pmd_t pmd) 212 { 213 return (pmd_val(pmd) == 214 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL); 215 } 216 217 #define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK) 218 219 static inline void pte_clear(struct mm_struct *mm, 220 unsigned long addr, pte_t *ptep) 221 { 222 pte_t null; 223 224 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf; 225 226 set_pte_at(mm, addr, ptep, null); 227 } 228 229 /* 230 * Conversion functions: convert a page and protection to a page entry, 231 * and a page entry and page directory to the page they refer to. 232 */ 233 #define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot)) 234 235 /* 236 * Conversion functions: convert a page and protection to a page entry, 237 * and a page entry and page directory to the page they refer to. 238 */ 239 #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd)) 240 #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT)) 241 242 static inline unsigned long pmd_page_vaddr(pmd_t pmd) 243 { 244 return pmd_val(pmd); 245 } 246 247 #define pte_ERROR(e) \ 248 pr_err("%s:%d: bad pte %08lx.\n", \ 249 __FILE__, __LINE__, pte_val(e)) 250 #define pgd_ERROR(e) \ 251 pr_err("%s:%d: bad pgd %08lx.\n", \ 252 __FILE__, __LINE__, pgd_val(e)) 253 254 /* 255 * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte): 256 * 257 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ... 1 0 258 * 0 0 0 0 type. 0 0 0 0 0 0 offset......... 259 * 260 * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file. 261 * 262 * Note that the offset field is always non-zero, thus !pte_none(pte) is always 263 * true. 264 */ 265 #define __swp_type(swp) (((swp).val >> 26) & 0x3) 266 #define __swp_offset(swp) ((swp).val & 0xfffff) 267 #define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x3) << 26) \ 268 | ((off) & 0xfffff) }) 269 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 270 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 271 272 #define kern_addr_valid(addr) (1) 273 274 extern void __init paging_init(void); 275 extern void __init mmu_init(void); 276 277 extern void update_mmu_cache(struct vm_area_struct *vma, 278 unsigned long address, pte_t *pte); 279 280 #endif /* _ASM_NIOS2_PGTABLE_H */ 281