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1#ifndef __ASM_SH_PGTABLE_64_H
2#define __ASM_SH_PGTABLE_64_H
3
4/*
5 * include/asm-sh/pgtable_64.h
6 *
7 * This file contains the functions and defines necessary to modify and use
8 * the SuperH page table tree.
9 *
10 * Copyright (C) 2000, 2001 Paolo Alberelli
11 * Copyright (C) 2003, 2004 Paul Mundt
12 * Copyright (C) 2003, 2004 Richard Curnow
13 *
14 * This file is subject to the terms and conditions of the GNU General Public
15 * License. See the file "COPYING" in the main directory of this archive
16 * for more details.
17 */
18#include <linux/threads.h>
19#include <asm/processor.h>
20#include <asm/page.h>
21
22/*
23 * Error outputs.
24 */
25#define pte_ERROR(e) \
26 printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e))
27#define pgd_ERROR(e) \
28 printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
29
30/*
31 * Table setting routines. Used within arch/mm only.
32 */
33#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
34
35static __inline__ void set_pte(pte_t *pteptr, pte_t pteval)
36{
37 unsigned long long x = ((unsigned long long) pteval.pte_low);
38 unsigned long long *xp = (unsigned long long *) pteptr;
39 /*
40 * Sign-extend based on NPHYS.
41 */
42 *(xp) = (x & NPHYS_SIGN) ? (x | NPHYS_MASK) : x;
43}
44#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
45
46/*
47 * PGD defines. Top level.
48 */
49
50/* To find an entry in a generic PGD. */
51#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
52#define __pgd_offset(address) pgd_index(address)
53#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
54
55/* To find an entry in a kernel PGD. */
56#define pgd_offset_k(address) pgd_offset(&init_mm, address)
57
58#define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
59#define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
60
61/*
62 * PMD level access routines. Same notes as above.
63 */
64#define _PMD_EMPTY 0x0
65/* Either the PMD is empty or present, it's not paged out */
66#define pmd_present(pmd_entry) (pmd_val(pmd_entry) & _PAGE_PRESENT)
67#define pmd_clear(pmd_entry_p) (set_pmd((pmd_entry_p), __pmd(_PMD_EMPTY)))
68#define pmd_none(pmd_entry) (pmd_val((pmd_entry)) == _PMD_EMPTY)
69#define pmd_bad(pmd_entry) ((pmd_val(pmd_entry) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
70
71#define pmd_page_vaddr(pmd_entry) \
72 ((unsigned long) __va(pmd_val(pmd_entry) & PAGE_MASK))
73
74#define pmd_page(pmd) \
75 (virt_to_page(pmd_val(pmd)))
76
77/* PMD to PTE dereferencing */
78#define pte_index(address) \
79 ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
80
81#define __pte_offset(address) pte_index(address)
82
83#define pte_offset_kernel(dir, addr) \
84 ((pte_t *) ((pmd_val(*(dir))) & PAGE_MASK) + pte_index((addr)))
85
86#define pte_offset_map(dir,addr) pte_offset_kernel(dir, addr)
87#define pte_unmap(pte) do { } while (0)
88
89#ifndef __ASSEMBLY__
90/*
91 * PTEL coherent flags.
92 * See Chapter 17 ST50 CPU Core Volume 1, Architecture.
93 */
94/* The bits that are required in the SH-5 TLB are placed in the h/w-defined
95 positions, to avoid expensive bit shuffling on every refill. The remaining
96 bits are used for s/w purposes and masked out on each refill.
97
98 Note, the PTE slots are used to hold data of type swp_entry_t when a page is
99 swapped out. Only the _PAGE_PRESENT flag is significant when the page is
100 swapped out, and it must be placed so that it doesn't overlap either the
101 type or offset fields of swp_entry_t. For x86, offset is at [31:8] and type
102 at [6:1], with _PAGE_PRESENT at bit 0 for both pte_t and swp_entry_t. This
103 scheme doesn't map to SH-5 because bit [0] controls cacheability. So bit
104 [2] is used for _PAGE_PRESENT and the type field of swp_entry_t is split
105 into 2 pieces. That is handled by SWP_ENTRY and SWP_TYPE below. */
106#define _PAGE_WT 0x001 /* CB0: if cacheable, 1->write-thru, 0->write-back */
107#define _PAGE_DEVICE 0x001 /* CB0: if uncacheable, 1->device (i.e. no write-combining or reordering at bus level) */
108#define _PAGE_CACHABLE 0x002 /* CB1: uncachable/cachable */
109#define _PAGE_PRESENT 0x004 /* software: page referenced */
110#define _PAGE_FILE 0x004 /* software: only when !present */
111#define _PAGE_SIZE0 0x008 /* SZ0-bit : size of page */
112#define _PAGE_SIZE1 0x010 /* SZ1-bit : size of page */
113#define _PAGE_SHARED 0x020 /* software: reflects PTEH's SH */
114#define _PAGE_READ 0x040 /* PR0-bit : read access allowed */
115#define _PAGE_EXECUTE 0x080 /* PR1-bit : execute access allowed */
116#define _PAGE_WRITE 0x100 /* PR2-bit : write access allowed */
117#define _PAGE_USER 0x200 /* PR3-bit : user space access allowed */
118#define _PAGE_DIRTY 0x400 /* software: page accessed in write */
119#define _PAGE_ACCESSED 0x800 /* software: page referenced */
120
121/* Wrapper for extended mode pgprot twiddling */
122#define _PAGE_EXT(x) ((unsigned long long)(x) << 32)
123
124/*
125 * We can use the sign-extended bits in the PTEL to get 32 bits of
126 * software flags. This works for now because no implementations uses
127 * anything above the PPN field.
128 */
129#define _PAGE_WIRED _PAGE_EXT(0x001) /* software: wire the tlb entry */
130#define _PAGE_SPECIAL _PAGE_EXT(0x002)
131
132#define _PAGE_CLEAR_FLAGS (_PAGE_PRESENT | _PAGE_FILE | _PAGE_SHARED | \
133 _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_WIRED)
134
135/* Mask which drops software flags */
136#define _PAGE_FLAGS_HARDWARE_MASK (NEFF_MASK & ~(_PAGE_CLEAR_FLAGS))
137
138/*
139 * HugeTLB support
140 */
141#if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
142#define _PAGE_SZHUGE (_PAGE_SIZE0)
143#elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
144#define _PAGE_SZHUGE (_PAGE_SIZE1)
145#elif defined(CONFIG_HUGETLB_PAGE_SIZE_512MB)
146#define _PAGE_SZHUGE (_PAGE_SIZE0 | _PAGE_SIZE1)
147#endif
148
149/*
150 * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
151 * to make pte_mkhuge() happy.
152 */
153#ifndef _PAGE_SZHUGE
154# define _PAGE_SZHUGE (0)
155#endif
156
157/*
158 * Default flags for a Kernel page.
159 * This is fundametally also SHARED because the main use of this define
160 * (other than for PGD/PMD entries) is for the VMALLOC pool which is
161 * contextless.
162 *
163 * _PAGE_EXECUTE is required for modules
164 *
165 */
166#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
167 _PAGE_EXECUTE | \
168 _PAGE_CACHABLE | _PAGE_ACCESSED | _PAGE_DIRTY | \
169 _PAGE_SHARED)
170
171/* Default flags for a User page */
172#define _PAGE_TABLE (_KERNPG_TABLE | _PAGE_USER)
173
174#define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | \
175 _PAGE_SPECIAL)
176
177/*
178 * We have full permissions (Read/Write/Execute/Shared).
179 */
180#define _PAGE_COMMON (_PAGE_PRESENT | _PAGE_USER | \
181 _PAGE_CACHABLE | _PAGE_ACCESSED)
182
183#define PAGE_NONE __pgprot(_PAGE_CACHABLE | _PAGE_ACCESSED)
184#define PAGE_SHARED __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_WRITE | \
185 _PAGE_SHARED)
186#define PAGE_EXECREAD __pgprot(_PAGE_COMMON | _PAGE_READ | _PAGE_EXECUTE)
187
188/*
189 * We need to include PAGE_EXECUTE in PAGE_COPY because it is the default
190 * protection mode for the stack.
191 */
192#define PAGE_COPY PAGE_EXECREAD
193
194#define PAGE_READONLY __pgprot(_PAGE_COMMON | _PAGE_READ)
195#define PAGE_WRITEONLY __pgprot(_PAGE_COMMON | _PAGE_WRITE)
196#define PAGE_RWX __pgprot(_PAGE_COMMON | _PAGE_READ | \
197 _PAGE_WRITE | _PAGE_EXECUTE)
198#define PAGE_KERNEL __pgprot(_KERNPG_TABLE)
199
200#define PAGE_KERNEL_NOCACHE \
201 __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
202 _PAGE_EXECUTE | _PAGE_ACCESSED | \
203 _PAGE_DIRTY | _PAGE_SHARED)
204
205/* Make it a device mapping for maximum safety (e.g. for mapping device
206 registers into user-space via /dev/map). */
207#define pgprot_noncached(x) __pgprot(((x).pgprot & ~(_PAGE_CACHABLE)) | _PAGE_DEVICE)
208#define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
209
210/*
211 * PTE level access routines.
212 *
213 * Note1:
214 * It's the tree walk leaf. This is physical address to be stored.
215 *
216 * Note 2:
217 * Regarding the choice of _PTE_EMPTY:
218
219 We must choose a bit pattern that cannot be valid, whether or not the page
220 is present. bit[2]==1 => present, bit[2]==0 => swapped out. If swapped
221 out, bits [31:8], [6:3], [1:0] are under swapper control, so only bit[7] is
222 left for us to select. If we force bit[7]==0 when swapped out, we could use
223 the combination bit[7,2]=2'b10 to indicate an empty PTE. Alternatively, if
224 we force bit[7]==1 when swapped out, we can use all zeroes to indicate
225 empty. This is convenient, because the page tables get cleared to zero
226 when they are allocated.
227
228 */
229#define _PTE_EMPTY 0x0
230#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
231#define pte_clear(mm,addr,xp) (set_pte_at(mm, addr, xp, __pte(_PTE_EMPTY)))
232#define pte_none(x) (pte_val(x) == _PTE_EMPTY)
233
234/*
235 * Some definitions to translate between mem_map, PTEs, and page
236 * addresses:
237 */
238
239/*
240 * Given a PTE, return the index of the mem_map[] entry corresponding
241 * to the page frame the PTE. Get the absolute physical address, make
242 * a relative physical address and translate it to an index.
243 */
244#define pte_pagenr(x) (((unsigned long) (pte_val(x)) - \
245 __MEMORY_START) >> PAGE_SHIFT)
246
247/*
248 * Given a PTE, return the "struct page *".
249 */
250#define pte_page(x) (mem_map + pte_pagenr(x))
251
252/*
253 * Return number of (down rounded) MB corresponding to x pages.
254 */
255#define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
256
257
258/*
259 * The following have defined behavior only work if pte_present() is true.
260 */
261static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
262static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
263static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
264static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
265static inline int pte_special(pte_t pte){ return pte_val(pte) & _PAGE_SPECIAL; }
266
267static inline pte_t pte_wrprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_WRITE)); return pte; }
268static inline pte_t pte_mkclean(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); return pte; }
269static inline pte_t pte_mkold(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); return pte; }
270static inline pte_t pte_mkwrite(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_WRITE)); return pte; }
271static inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
272static inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
273static inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SZHUGE)); return pte; }
274static inline pte_t pte_mkspecial(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SPECIAL)); return pte; }
275
276/*
277 * Conversion functions: convert a page and protection to a page entry.
278 *
279 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
280 */
281#define mk_pte(page,pgprot) \
282({ \
283 pte_t __pte; \
284 \
285 set_pte(&__pte, __pte((((page)-mem_map) << PAGE_SHIFT) | \
286 __MEMORY_START | pgprot_val((pgprot)))); \
287 __pte; \
288})
289
290/*
291 * This takes a (absolute) physical page address that is used
292 * by the remapping functions
293 */
294#define mk_pte_phys(physpage, pgprot) \
295({ pte_t __pte; set_pte(&__pte, __pte(physpage | pgprot_val(pgprot))); __pte; })
296
297static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
298{ set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot))); return pte; }
299
300/* Encode and decode a swap entry */
301#define __swp_type(x) (((x).val & 3) + (((x).val >> 1) & 0x3c))
302#define __swp_offset(x) ((x).val >> 8)
303#define __swp_entry(type, offset) ((swp_entry_t) { ((offset << 8) + ((type & 0x3c) << 1) + (type & 3)) })
304#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
305#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
306
307/* Encode and decode a nonlinear file mapping entry */
308#define PTE_FILE_MAX_BITS 29
309#define pte_to_pgoff(pte) (pte_val(pte))
310#define pgoff_to_pte(off) ((pte_t) { (off) | _PAGE_FILE })
311
312#endif /* !__ASSEMBLY__ */
313
314#define pfn_pte(pfn, prot) __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
315#define pfn_pmd(pfn, prot) __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
316
317#endif /* __ASM_SH_PGTABLE_64_H */