2 * Copyright (C) 2004-2006 Atmel Corporation
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.
8 #ifndef __ASM_AVR32_PGTABLE_H
9 #define __ASM_AVR32_PGTABLE_H
11 #include <asm/addrspace.h>
14 #include <linux/sched.h>
16 #endif /* !__ASSEMBLY__ */
19 * Use two-level page tables just as the i386 (without PAE)
21 #include <asm/pgtable-2level.h>
24 * The following code might need some cleanup when the values are
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))
32 #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
33 #define FIRST_USER_ADDRESS 0
35 #define PTE_PHYS_MASK 0x1ffff000
38 extern pgd_t swapper_pg_dir
[PTRS_PER_PGD
];
39 extern void paging_init(void);
42 * ZERO_PAGE is a global shared page that is always zero: used for
43 * zero-mapped memory areas etc.
45 extern struct page
*empty_zero_page
;
46 #define ZERO_PAGE(vaddr) (empty_zero_page)
49 * Just any arbitrary offset to the start of the vmalloc VM area: the
50 * current 8 MiB value just means that there will be a 8 MiB "hole"
51 * after the uncached physical memory (P2 segment) until the vmalloc
52 * area starts. That means that any out-of-bounds memory accesses will
53 * hopefully be caught; we don't know if the end of the P1/P2 segments
54 * are actually used for anything, but it is anyway safer to let the
55 * MMU catch these kinds of errors than to rely on the memory bus.
57 * A "hole" of the same size is added to the end of the P3 segment as
58 * well. It might seem wasteful to use 16 MiB of virtual address space
59 * on this, but we do have 512 MiB of it...
61 * The vmalloc() routines leave a hole of 4 KiB between each vmalloced
62 * area for the same reason.
64 #define VMALLOC_OFFSET (8 * 1024 * 1024)
65 #define VMALLOC_START (P3SEG + VMALLOC_OFFSET)
66 #define VMALLOC_END (P4SEG - VMALLOC_OFFSET)
67 #endif /* !__ASSEMBLY__ */
70 * Page flags. Some of these flags are not directly supported by
71 * hardware, so we have to emulate them.
73 #define _TLBEHI_BIT_VALID 9
74 #define _TLBEHI_VALID (1 << _TLBEHI_BIT_VALID)
76 #define _PAGE_BIT_WT 0 /* W-bit : write-through */
77 #define _PAGE_BIT_DIRTY 1 /* D-bit : page changed */
78 #define _PAGE_BIT_SZ0 2 /* SZ0-bit : Size of page */
79 #define _PAGE_BIT_SZ1 3 /* SZ1-bit : Size of page */
80 #define _PAGE_BIT_EXECUTE 4 /* X-bit : execute access allowed */
81 #define _PAGE_BIT_RW 5 /* AP0-bit : write access allowed */
82 #define _PAGE_BIT_USER 6 /* AP1-bit : user space access allowed */
83 #define _PAGE_BIT_BUFFER 7 /* B-bit : bufferable */
84 #define _PAGE_BIT_GLOBAL 8 /* G-bit : global (ignore ASID) */
85 #define _PAGE_BIT_CACHABLE 9 /* C-bit : cachable */
87 /* If we drop support for 1K pages, we get two extra bits */
88 #define _PAGE_BIT_PRESENT 10
89 #define _PAGE_BIT_ACCESSED 11 /* software: page was accessed */
91 /* The following flags are only valid when !PRESENT */
92 #define _PAGE_BIT_FILE 0 /* software: pagecache or swap? */
94 #define _PAGE_WT (1 << _PAGE_BIT_WT)
95 #define _PAGE_DIRTY (1 << _PAGE_BIT_DIRTY)
96 #define _PAGE_EXECUTE (1 << _PAGE_BIT_EXECUTE)
97 #define _PAGE_RW (1 << _PAGE_BIT_RW)
98 #define _PAGE_USER (1 << _PAGE_BIT_USER)
99 #define _PAGE_BUFFER (1 << _PAGE_BIT_BUFFER)
100 #define _PAGE_GLOBAL (1 << _PAGE_BIT_GLOBAL)
101 #define _PAGE_CACHABLE (1 << _PAGE_BIT_CACHABLE)
104 #define _PAGE_ACCESSED (1 << _PAGE_BIT_ACCESSED)
105 #define _PAGE_PRESENT (1 << _PAGE_BIT_PRESENT)
106 #define _PAGE_FILE (1 << _PAGE_BIT_FILE)
109 * Page types, i.e. sizes. _PAGE_TYPE_NONE corresponds to what is
110 * usually called _PAGE_PROTNONE on other architectures.
112 * XXX: Find out if _PAGE_PROTNONE is equivalent with !_PAGE_USER. If
113 * so, we can encode all possible page sizes (although we can't really
114 * support 1K pages anyway due to the _PAGE_PRESENT and _PAGE_ACCESSED
118 #define _PAGE_TYPE_MASK ((1 << _PAGE_BIT_SZ0) | (1 << _PAGE_BIT_SZ1))
119 #define _PAGE_TYPE_NONE (0 << _PAGE_BIT_SZ0)
120 #define _PAGE_TYPE_SMALL (1 << _PAGE_BIT_SZ0)
121 #define _PAGE_TYPE_MEDIUM (2 << _PAGE_BIT_SZ0)
122 #define _PAGE_TYPE_LARGE (3 << _PAGE_BIT_SZ0)
125 * Mask which drop software flags. We currently can't handle more than
126 * 512 MiB of physical memory, so we can use bits 29-31 for other
127 * stuff. With a fixed 4K page size, we can use bits 10-11 as well as
130 #define _PAGE_FLAGS_HARDWARE_MASK 0xfffff3ff
132 #define _PAGE_FLAGS_CACHE_MASK (_PAGE_CACHABLE | _PAGE_BUFFER | _PAGE_WT)
134 /* TODO: Check for saneness */
135 /* User-mode page table flags (to be set in a pgd or pmd entry) */
136 #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_TYPE_SMALL | _PAGE_RW \
137 | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
138 /* Kernel-mode page table flags */
139 #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_TYPE_SMALL | _PAGE_RW \
140 | _PAGE_ACCESSED | _PAGE_DIRTY)
141 /* Flags that may be modified by software */
142 #define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY \
143 | _PAGE_FLAGS_CACHE_MASK)
145 #define _PAGE_FLAGS_READ (_PAGE_CACHABLE | _PAGE_BUFFER)
146 #define _PAGE_FLAGS_WRITE (_PAGE_FLAGS_READ | _PAGE_RW | _PAGE_DIRTY)
148 #define _PAGE_NORMAL(x) __pgprot((x) | _PAGE_PRESENT | _PAGE_TYPE_SMALL \
151 #define PAGE_NONE (_PAGE_ACCESSED | _PAGE_TYPE_NONE)
152 #define PAGE_READ (_PAGE_FLAGS_READ | _PAGE_USER)
153 #define PAGE_EXEC (_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_USER)
154 #define PAGE_WRITE (_PAGE_FLAGS_WRITE | _PAGE_USER)
155 #define PAGE_KERNEL _PAGE_NORMAL(_PAGE_FLAGS_WRITE | _PAGE_EXECUTE | _PAGE_GLOBAL)
156 #define PAGE_KERNEL_RO _PAGE_NORMAL(_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_GLOBAL)
158 #define _PAGE_P(x) _PAGE_NORMAL((x) & ~(_PAGE_RW | _PAGE_DIRTY))
159 #define _PAGE_S(x) _PAGE_NORMAL(x)
161 #define PAGE_COPY _PAGE_P(PAGE_WRITE | PAGE_READ)
165 * The hardware supports flags for write- and execute access. Read is
166 * always allowed if the page is loaded into the TLB, so the "-w-",
167 * "--x" and "-wx" mappings are implemented as "rw-", "r-x" and "rwx",
170 * The "---" case is handled by software; the page will simply not be
171 * loaded into the TLB if the page type is _PAGE_TYPE_NONE.
174 #define __P000 __pgprot(PAGE_NONE)
175 #define __P001 _PAGE_P(PAGE_READ)
176 #define __P010 _PAGE_P(PAGE_WRITE)
177 #define __P011 _PAGE_P(PAGE_WRITE | PAGE_READ)
178 #define __P100 _PAGE_P(PAGE_EXEC)
179 #define __P101 _PAGE_P(PAGE_EXEC | PAGE_READ)
180 #define __P110 _PAGE_P(PAGE_EXEC | PAGE_WRITE)
181 #define __P111 _PAGE_P(PAGE_EXEC | PAGE_WRITE | PAGE_READ)
183 #define __S000 __pgprot(PAGE_NONE)
184 #define __S001 _PAGE_S(PAGE_READ)
185 #define __S010 _PAGE_S(PAGE_WRITE)
186 #define __S011 _PAGE_S(PAGE_WRITE | PAGE_READ)
187 #define __S100 _PAGE_S(PAGE_EXEC)
188 #define __S101 _PAGE_S(PAGE_EXEC | PAGE_READ)
189 #define __S110 _PAGE_S(PAGE_EXEC | PAGE_WRITE)
190 #define __S111 _PAGE_S(PAGE_EXEC | PAGE_WRITE | PAGE_READ)
192 #define pte_none(x) (!pte_val(x))
193 #define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
195 #define pte_clear(mm,addr,xp) \
197 set_pte_at(mm, addr, xp, __pte(0)); \
201 * The following only work if pte_present() is true.
202 * Undefined behaviour if not..
204 static inline int pte_read(pte_t pte
)
206 return pte_val(pte
) & _PAGE_USER
;
208 static inline int pte_write(pte_t pte
)
210 return pte_val(pte
) & _PAGE_RW
;
212 static inline int pte_exec(pte_t pte
)
214 return pte_val(pte
) & _PAGE_EXECUTE
;
216 static inline int pte_dirty(pte_t pte
)
218 return pte_val(pte
) & _PAGE_DIRTY
;
220 static inline int pte_young(pte_t pte
)
222 return pte_val(pte
) & _PAGE_ACCESSED
;
226 * The following only work if pte_present() is not true.
228 static inline int pte_file(pte_t pte
)
230 return pte_val(pte
) & _PAGE_FILE
;
233 /* Mutator functions for PTE bits */
234 static inline pte_t
pte_rdprotect(pte_t pte
)
236 set_pte(&pte
, __pte(pte_val(pte
) & ~_PAGE_USER
));
239 static inline pte_t
pte_wrprotect(pte_t pte
)
241 set_pte(&pte
, __pte(pte_val(pte
) & ~_PAGE_RW
));
244 static inline pte_t
pte_exprotect(pte_t pte
)
246 set_pte(&pte
, __pte(pte_val(pte
) & ~_PAGE_EXECUTE
));
249 static inline pte_t
pte_mkclean(pte_t pte
)
251 set_pte(&pte
, __pte(pte_val(pte
) & ~_PAGE_DIRTY
));
254 static inline pte_t
pte_mkold(pte_t pte
)
256 set_pte(&pte
, __pte(pte_val(pte
) & ~_PAGE_ACCESSED
));
259 static inline pte_t
pte_mkread(pte_t pte
)
261 set_pte(&pte
, __pte(pte_val(pte
) | _PAGE_USER
));
264 static inline pte_t
pte_mkwrite(pte_t pte
)
266 set_pte(&pte
, __pte(pte_val(pte
) | _PAGE_RW
));
269 static inline pte_t
pte_mkexec(pte_t pte
)
271 set_pte(&pte
, __pte(pte_val(pte
) | _PAGE_EXECUTE
));
274 static inline pte_t
pte_mkdirty(pte_t pte
)
276 set_pte(&pte
, __pte(pte_val(pte
) | _PAGE_DIRTY
));
279 static inline pte_t
pte_mkyoung(pte_t pte
)
281 set_pte(&pte
, __pte(pte_val(pte
) | _PAGE_ACCESSED
));
285 #define pmd_none(x) (!pmd_val(x))
286 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
287 #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
288 #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) \
292 * Permanent address of a page. We don't support highmem, so this is
295 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
296 #define pte_page(x) phys_to_page(pte_val(x) & PTE_PHYS_MASK)
299 * Mark the prot value as uncacheable and unbufferable
301 #define pgprot_noncached(prot) \
302 __pgprot(pgprot_val(prot) & ~(_PAGE_BUFFER | _PAGE_CACHABLE))
305 * Mark the prot value as uncacheable but bufferable
307 #define pgprot_writecombine(prot) \
308 __pgprot((pgprot_val(prot) & ~_PAGE_CACHABLE) | _PAGE_BUFFER)
311 * Conversion functions: convert a page and protection to a page entry,
312 * and a page entry and page directory to the page they refer to.
314 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
316 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
318 static inline pte_t
pte_modify(pte_t pte
, pgprot_t newprot
)
320 set_pte(&pte
, __pte((pte_val(pte
) & _PAGE_CHG_MASK
)
321 | pgprot_val(newprot
)));
325 #define page_pte(page) page_pte_prot(page, __pgprot(0))
327 #define pmd_page_vaddr(pmd) \
328 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
330 #define pmd_page(pmd) (phys_to_page(pmd_val(pmd)))
332 /* to find an entry in a page-table-directory. */
333 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
334 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
335 #define pgd_offset_current(address) \
336 ((pgd_t *)__mfsr(SYSREG_PTBR) + pgd_index(address))
338 /* to find an entry in a kernel page-table-directory */
339 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
341 /* Find an entry in the third-level page table.. */
342 #define pte_index(address) \
343 ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
344 #define pte_offset(dir, address) \
345 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
346 #define pte_offset_kernel(dir, address) \
347 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
348 #define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
349 #define pte_offset_map_nested(dir, address) pte_offset_kernel(dir, address)
350 #define pte_unmap(pte) do { } while (0)
351 #define pte_unmap_nested(pte) do { } while (0)
353 struct vm_area_struct
;
354 extern void update_mmu_cache(struct vm_area_struct
* vma
,
355 unsigned long address
, pte_t pte
);
358 * Encode and decode a swap entry
361 * _PAGE_FILE at bit 0
362 * _PAGE_TYPE_* at bits 2-3 (for emulating _PAGE_PROTNONE)
363 * _PAGE_PRESENT at bit 10
365 * We encode the type into bits 4-9 and offset into bits 11-31. This
366 * gives us a 21 bits offset, or 2**21 * 4K = 8G usable swap space per
367 * device, and 64 possible types.
369 * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
370 * and _PAGE_PROTNONE bits
372 #define __swp_type(x) (((x).val >> 4) & 0x3f)
373 #define __swp_offset(x) ((x).val >> 11)
374 #define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
375 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
376 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
379 * Encode and decode a nonlinear file mapping entry. We have to
380 * preserve _PAGE_FILE and _PAGE_PRESENT here. _PAGE_TYPE_* isn't
381 * necessary, since _PAGE_FILE implies !_PAGE_PROTNONE (?)
383 #define PTE_FILE_MAX_BITS 30
384 #define pte_to_pgoff(pte) (((pte_val(pte) >> 1) & 0x1ff) \
385 | ((pte_val(pte) >> 11) << 9))
386 #define pgoff_to_pte(off) ((pte_t) { ((((off) & 0x1ff) << 1) \
387 | (((off) >> 9) << 11) \
390 typedef pte_t
*pte_addr_t
;
392 #define kern_addr_valid(addr) (1)
394 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
395 remap_pfn_range(vma, vaddr, pfn, size, prot)
397 #define MK_IOSPACE_PFN(space, pfn) (pfn)
398 #define GET_IOSPACE(pfn) 0
399 #define GET_PFN(pfn) (pfn)
401 /* No page table caches to initialize (?) */
402 #define pgtable_cache_init() do { } while(0)
404 #include <asm-generic/pgtable.h>
406 #endif /* !__ASSEMBLY__ */
408 #endif /* __ASM_AVR32_PGTABLE_H */