1/* 2 * Copyright (C) 2004-2006 Atmel Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8#ifndef __ASM_AVR32_PGTABLE_H 9#define __ASM_AVR32_PGTABLE_H 10 11#include <asm/addrspace.h> 12 13#ifndef __ASSEMBLY__ 14#include <linux/sched.h> 15 16#endif /* !__ASSEMBLY__ */ 17 18/* 19 * Use two-level page tables just as the i386 (without PAE) 20 */ 21#include <asm/pgtable-2level.h> 22 23/* 24 * The following code might need some cleanup when the values are 25 * final... 26 */ 27#define PMD_SIZE (1UL << PMD_SHIFT) 28#define PMD_MASK (~(PMD_SIZE-1)) 29#define PGDIR_SIZE (1UL << PGDIR_SHIFT) 30#define PGDIR_MASK (~(PGDIR_SIZE-1)) 31 32#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) 33#define FIRST_USER_ADDRESS 0 34 35#ifndef __ASSEMBLY__ 36extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 37extern void paging_init(void); 38 39/* 40 * ZERO_PAGE is a global shared page that is always zero: used for 41 * zero-mapped memory areas etc. 42 */ 43extern struct page *empty_zero_page; 44#define ZERO_PAGE(vaddr) (empty_zero_page) 45 46/* 47 * Just any arbitrary offset to the start of the vmalloc VM area: the 48 * current 8 MiB value just means that there will be a 8 MiB "hole" 49 * after the uncached physical memory (P2 segment) until the vmalloc 50 * area starts. That means that any out-of-bounds memory accesses will 51 * hopefully be caught; we don't know if the end of the P1/P2 segments 52 * are actually used for anything, but it is anyway safer to let the 53 * MMU catch these kinds of errors than to rely on the memory bus. 54 * 55 * A "hole" of the same size is added to the end of the P3 segment as 56 * well. It might seem wasteful to use 16 MiB of virtual address space 57 * on this, but we do have 512 MiB of it... 58 * 59 * The vmalloc() routines leave a hole of 4 KiB between each vmalloced 60 * area for the same reason. 61 */ 62#define VMALLOC_OFFSET (8 * 1024 * 1024) 63#define VMALLOC_START (P3SEG + VMALLOC_OFFSET) 64#define VMALLOC_END (P4SEG - VMALLOC_OFFSET) 65#endif /* !__ASSEMBLY__ */ 66 67/* 68 * Page flags. Some of these flags are not directly supported by 69 * hardware, so we have to emulate them. 70 */ 71#define _TLBEHI_BIT_VALID 9 72#define _TLBEHI_VALID (1 << _TLBEHI_BIT_VALID) 73 74#define _PAGE_BIT_WT 0 /* W-bit : write-through */ 75#define _PAGE_BIT_DIRTY 1 /* D-bit : page changed */ 76#define _PAGE_BIT_SZ0 2 /* SZ0-bit : Size of page */ 77#define _PAGE_BIT_SZ1 3 /* SZ1-bit : Size of page */ 78#define _PAGE_BIT_EXECUTE 4 /* X-bit : execute access allowed */ 79#define _PAGE_BIT_RW 5 /* AP0-bit : write access allowed */ 80#define _PAGE_BIT_USER 6 /* AP1-bit : user space access allowed */ 81#define _PAGE_BIT_BUFFER 7 /* B-bit : bufferable */ 82#define _PAGE_BIT_GLOBAL 8 /* G-bit : global (ignore ASID) */ 83#define _PAGE_BIT_CACHABLE 9 /* C-bit : cachable */ 84 85/* If we drop support for 1K pages, we get two extra bits */ 86#define _PAGE_BIT_PRESENT 10 87#define _PAGE_BIT_ACCESSED 11 /* software: page was accessed */ 88 89/* The following flags are only valid when !PRESENT */ 90#define _PAGE_BIT_FILE 0 /* software: pagecache or swap? */ 91 92#define _PAGE_WT (1 << _PAGE_BIT_WT) 93#define _PAGE_DIRTY (1 << _PAGE_BIT_DIRTY) 94#define _PAGE_EXECUTE (1 << _PAGE_BIT_EXECUTE) 95#define _PAGE_RW (1 << _PAGE_BIT_RW) 96#define _PAGE_USER (1 << _PAGE_BIT_USER) 97#define _PAGE_BUFFER (1 << _PAGE_BIT_BUFFER) 98#define _PAGE_GLOBAL (1 << _PAGE_BIT_GLOBAL) 99#define _PAGE_CACHABLE (1 << _PAGE_BIT_CACHABLE) 100 101/* Software flags */ 102#define _PAGE_ACCESSED (1 << _PAGE_BIT_ACCESSED) 103#define _PAGE_PRESENT (1 << _PAGE_BIT_PRESENT) 104#define _PAGE_FILE (1 << _PAGE_BIT_FILE) 105 106#define _PAGE_TYPE_MASK ((1 << _PAGE_BIT_SZ0) | (1 << _PAGE_BIT_SZ1)) 107#define _PAGE_TYPE_NONE (0 << _PAGE_BIT_SZ0) 108#define _PAGE_TYPE_SMALL (1 << _PAGE_BIT_SZ0) 109#define _PAGE_TYPE_MEDIUM (2 << _PAGE_BIT_SZ0) 110#define _PAGE_TYPE_LARGE (3 << _PAGE_BIT_SZ0) 111 112/* 113 * Mask which drop software flags. We currently can't handle more than 114 * 512 MiB of physical memory, so we can use bits 29-31 for other 115 * stuff. With a fixed 4K page size, we can use bits 10-11 as well as 116 * bits 2-3 (SZ) 117 */ 118#define _PAGE_FLAGS_HARDWARE_MASK 0xfffff3ff 119 120#define _PAGE_FLAGS_CACHE_MASK (_PAGE_CACHABLE | _PAGE_BUFFER | _PAGE_WT) 121 122/* Flags that may be modified by software */ 123#define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY \ 124 | _PAGE_FLAGS_CACHE_MASK) 125 126#define _PAGE_FLAGS_READ (_PAGE_CACHABLE | _PAGE_BUFFER) 127#define _PAGE_FLAGS_WRITE (_PAGE_FLAGS_READ | _PAGE_RW | _PAGE_DIRTY) 128 129#define _PAGE_NORMAL(x) __pgprot((x) | _PAGE_PRESENT | _PAGE_TYPE_SMALL \ 130 | _PAGE_ACCESSED) 131 132#define PAGE_NONE (_PAGE_ACCESSED | _PAGE_TYPE_NONE) 133#define PAGE_READ (_PAGE_FLAGS_READ | _PAGE_USER) 134#define PAGE_EXEC (_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_USER) 135#define PAGE_WRITE (_PAGE_FLAGS_WRITE | _PAGE_USER) 136#define PAGE_KERNEL _PAGE_NORMAL(_PAGE_FLAGS_WRITE | _PAGE_EXECUTE | _PAGE_GLOBAL) 137#define PAGE_KERNEL_RO _PAGE_NORMAL(_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_GLOBAL) 138 139#define _PAGE_P(x) _PAGE_NORMAL((x) & ~(_PAGE_RW | _PAGE_DIRTY)) 140#define _PAGE_S(x) _PAGE_NORMAL(x) 141 142#define PAGE_COPY _PAGE_P(PAGE_WRITE | PAGE_READ) 143#define PAGE_SHARED _PAGE_S(PAGE_WRITE | PAGE_READ) 144 145#ifndef __ASSEMBLY__ 146/* 147 * The hardware supports flags for write- and execute access. Read is 148 * always allowed if the page is loaded into the TLB, so the "-w-", 149 * "--x" and "-wx" mappings are implemented as "rw-", "r-x" and "rwx", 150 * respectively. 151 * 152 * The "---" case is handled by software; the page will simply not be 153 * loaded into the TLB if the page type is _PAGE_TYPE_NONE. 154 */ 155 156#define __P000 __pgprot(PAGE_NONE) 157#define __P001 _PAGE_P(PAGE_READ) 158#define __P010 _PAGE_P(PAGE_WRITE) 159#define __P011 _PAGE_P(PAGE_WRITE | PAGE_READ) 160#define __P100 _PAGE_P(PAGE_EXEC) 161#define __P101 _PAGE_P(PAGE_EXEC | PAGE_READ) 162#define __P110 _PAGE_P(PAGE_EXEC | PAGE_WRITE) 163#define __P111 _PAGE_P(PAGE_EXEC | PAGE_WRITE | PAGE_READ) 164 165#define __S000 __pgprot(PAGE_NONE) 166#define __S001 _PAGE_S(PAGE_READ) 167#define __S010 _PAGE_S(PAGE_WRITE) 168#define __S011 _PAGE_S(PAGE_WRITE | PAGE_READ) 169#define __S100 _PAGE_S(PAGE_EXEC) 170#define __S101 _PAGE_S(PAGE_EXEC | PAGE_READ) 171#define __S110 _PAGE_S(PAGE_EXEC | PAGE_WRITE) 172#define __S111 _PAGE_S(PAGE_EXEC | PAGE_WRITE | PAGE_READ) 173 174#define pte_none(x) (!pte_val(x)) 175#define pte_present(x) (pte_val(x) & _PAGE_PRESENT) 176 177#define pte_clear(mm,addr,xp) \ 178 do { \ 179 set_pte_at(mm, addr, xp, __pte(0)); \ 180 } while (0) 181 182/* 183 * The following only work if pte_present() is true. 184 * Undefined behaviour if not.. 185 */ 186static inline int pte_write(pte_t pte) 187{ 188 return pte_val(pte) & _PAGE_RW; 189} 190static inline int pte_dirty(pte_t pte) 191{ 192 return pte_val(pte) & _PAGE_DIRTY; 193} 194static inline int pte_young(pte_t pte) 195{ 196 return pte_val(pte) & _PAGE_ACCESSED; 197} 198static inline int pte_special(pte_t pte) 199{ 200 return 0; 201} 202 203/* 204 * The following only work if pte_present() is not true. 205 */ 206static inline int pte_file(pte_t pte) 207{ 208 return pte_val(pte) & _PAGE_FILE; 209} 210 211/* Mutator functions for PTE bits */ 212static inline pte_t pte_wrprotect(pte_t pte) 213{ 214 set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_RW)); 215 return pte; 216} 217static inline pte_t pte_mkclean(pte_t pte) 218{ 219 set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); 220 return pte; 221} 222static inline pte_t pte_mkold(pte_t pte) 223{ 224 set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); 225 return pte; 226} 227static inline pte_t pte_mkwrite(pte_t pte) 228{ 229 set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); 230 return pte; 231} 232static inline pte_t pte_mkdirty(pte_t pte) 233{ 234 set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); 235 return pte; 236} 237static inline pte_t pte_mkyoung(pte_t pte) 238{ 239 set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); 240 return pte; 241} 242static inline pte_t pte_mkspecial(pte_t pte) 243{ 244 return pte; 245} 246 247#define pmd_none(x) (!pmd_val(x)) 248#define pmd_present(x) (pmd_val(x)) 249 250static inline void pmd_clear(pmd_t *pmdp) 251{ 252 set_pmd(pmdp, __pmd(0)); 253} 254 255#define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK) 256 257/* 258 * Permanent address of a page. We don't support highmem, so this is 259 * trivial. 260 */ 261#define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT)) 262#define pte_page(x) (pfn_to_page(pte_pfn(x))) 263 264/* 265 * Mark the prot value as uncacheable and unbufferable 266 */ 267#define pgprot_noncached(prot) \ 268 __pgprot(pgprot_val(prot) & ~(_PAGE_BUFFER | _PAGE_CACHABLE)) 269 270/* 271 * Mark the prot value as uncacheable but bufferable 272 */ 273#define pgprot_writecombine(prot) \ 274 __pgprot((pgprot_val(prot) & ~_PAGE_CACHABLE) | _PAGE_BUFFER) 275 276/* 277 * Conversion functions: convert a page and protection to a page entry, 278 * and a page entry and page directory to the page they refer to. 279 * 280 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot) 281 */ 282#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot)) 283 284static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 285{ 286 set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) 287 | pgprot_val(newprot))); 288 return pte; 289} 290 291#define page_pte(page) page_pte_prot(page, __pgprot(0)) 292 293#define pmd_page_vaddr(pmd) pmd_val(pmd) 294#define pmd_page(pmd) (virt_to_page(pmd_val(pmd))) 295 296/* to find an entry in a page-table-directory. */ 297#define pgd_index(address) (((address) >> PGDIR_SHIFT) \ 298 & (PTRS_PER_PGD - 1)) 299#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address)) 300 301/* to find an entry in a kernel page-table-directory */ 302#define pgd_offset_k(address) pgd_offset(&init_mm, address) 303 304/* Find an entry in the third-level page table.. */ 305#define pte_index(address) \ 306 ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 307#define pte_offset(dir, address) \ 308 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address)) 309#define pte_offset_kernel(dir, address) \ 310 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address)) 311#define pte_offset_map(dir, address) pte_offset_kernel(dir, address) 312#define pte_offset_map_nested(dir, address) pte_offset_kernel(dir, address) 313#define pte_unmap(pte) do { } while (0) 314#define pte_unmap_nested(pte) do { } while (0) 315 316struct vm_area_struct; 317extern void update_mmu_cache(struct vm_area_struct * vma, 318 unsigned long address, pte_t *ptep); 319 320/* 321 * Encode and decode a swap entry 322 * 323 * Constraints: 324 * _PAGE_FILE at bit 0 325 * _PAGE_TYPE_* at bits 2-3 (for emulating _PAGE_PROTNONE) 326 * _PAGE_PRESENT at bit 10 327 * 328 * We encode the type into bits 4-9 and offset into bits 11-31. This 329 * gives us a 21 bits offset, or 2**21 * 4K = 8G usable swap space per 330 * device, and 64 possible types. 331 * 332 * NOTE: We should set ZEROs at the position of _PAGE_PRESENT 333 * and _PAGE_PROTNONE bits 334 */ 335#define __swp_type(x) (((x).val >> 4) & 0x3f) 336#define __swp_offset(x) ((x).val >> 11) 337#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 11) }) 338#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 339#define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 340 341/* 342 * Encode and decode a nonlinear file mapping entry. We have to 343 * preserve _PAGE_FILE and _PAGE_PRESENT here. _PAGE_TYPE_* isn't 344 * necessary, since _PAGE_FILE implies !_PAGE_PROTNONE (?) 345 */ 346#define PTE_FILE_MAX_BITS 30 347#define pte_to_pgoff(pte) (((pte_val(pte) >> 1) & 0x1ff) \ 348 | ((pte_val(pte) >> 11) << 9)) 349#define pgoff_to_pte(off) ((pte_t) { ((((off) & 0x1ff) << 1) \ 350 | (((off) >> 9) << 11) \ 351 | _PAGE_FILE) }) 352 353typedef pte_t *pte_addr_t; 354 355#define kern_addr_valid(addr) (1) 356 357#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \ 358 remap_pfn_range(vma, vaddr, pfn, size, prot) 359 360/* No page table caches to initialize (?) */ 361#define pgtable_cache_init() do { } while(0) 362 363#include <asm-generic/pgtable.h> 364 365#endif /* !__ASSEMBLY__ */ 366 367#endif /* __ASM_AVR32_PGTABLE_H */ 368