summaryrefslogtreecommitdiffstats
path: root/arch/nios2/include/asm/pgtable.h
blob: 4a995fa628eef81e386d8530de1fca17d5a98bc7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
/*
 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2009 Wind River Systems Inc
 *
 * Based on asm/pgtable-32.h from mips which is:
 *
 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#ifndef _ASM_NIOS2_PGTABLE_H
#define _ASM_NIOS2_PGTABLE_H

#include <linux/io.h>
#include <linux/bug.h>
#include <asm/page.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>

#include <asm/pgtable-bits.h>
#include <asm-generic/pgtable-nopmd.h>

#define VMALLOC_START		CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
#define VMALLOC_END		(CONFIG_NIOS2_KERNEL_REGION_BASE - 1)

struct mm_struct;

/* Helper macro */
#define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED |		\
				((x) ? _PAGE_EXEC : 0) |		\
				((r) ? _PAGE_READ : 0) |		\
				((w) ? _PAGE_WRITE : 0))
/*
 * These are the macros that generic kernel code needs
 * (to populate protection_map[])
 */

/* Remove W bit on private pages for COW support */
#define __P000	MKP(0, 0, 0)
#define __P001	MKP(0, 0, 1)
#define __P010	MKP(0, 0, 0)	/* COW */
#define __P011	MKP(0, 0, 1)	/* COW */
#define __P100	MKP(1, 0, 0)
#define __P101	MKP(1, 0, 1)
#define __P110	MKP(1, 0, 0)	/* COW */
#define __P111	MKP(1, 0, 1)	/* COW */

/* Shared pages can have exact HW mapping */
#define __S000	MKP(0, 0, 0)
#define __S001	MKP(0, 0, 1)
#define __S010	MKP(0, 1, 0)
#define __S011	MKP(0, 1, 1)
#define __S100	MKP(1, 0, 0)
#define __S101	MKP(1, 0, 1)
#define __S110	MKP(1, 1, 0)
#define __S111	MKP(1, 1, 1)

/* Used all over the kernel */
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
			     _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL)

#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
			     _PAGE_WRITE | _PAGE_ACCESSED)

#define PAGE_COPY MKP(0, 0, 1)

#define PGD_ORDER	0
#define PTE_ORDER	0

#define PTRS_PER_PGD	((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
#define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))

#define USER_PTRS_PER_PGD	\
	(CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE)

#define PGDIR_SHIFT	22
#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
#define PGDIR_MASK	(~(PGDIR_SIZE-1))

/*
 * ZERO_PAGE is a global shared page that is always zero: used
 * for zero-mapped memory areas etc..
 */
extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
#define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))

extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];

/*
 * (pmds are folded into puds so this doesn't get actually called,
 * but the define is needed for a generic inline function.)
 */
static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval)
{
	*pmdptr = pmdval;
}

static inline int pte_write(pte_t pte)		\
	{ return pte_val(pte) & _PAGE_WRITE; }
static inline int pte_dirty(pte_t pte)		\
	{ return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte)		\
	{ return pte_val(pte) & _PAGE_ACCESSED; }

#define pgprot_noncached pgprot_noncached

static inline pgprot_t pgprot_noncached(pgprot_t _prot)
{
	unsigned long prot = pgprot_val(_prot);

	prot &= ~_PAGE_CACHED;

	return __pgprot(prot);
}

static inline int pte_none(pte_t pte)
{
	return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf));
}

static inline int pte_present(pte_t pte)	\
	{ return pte_val(pte) & _PAGE_PRESENT; }

/*
 * The following only work if pte_present() is true.
 * Undefined behaviour if not..
 */
static inline pte_t pte_wrprotect(pte_t pte)
{
	pte_val(pte) &= ~_PAGE_WRITE;
	return pte;
}

static inline pte_t pte_mkclean(pte_t pte)
{
	pte_val(pte) &= ~_PAGE_DIRTY;
	return pte;
}

static inline pte_t pte_mkold(pte_t pte)
{
	pte_val(pte) &= ~_PAGE_ACCESSED;
	return pte;
}

static inline pte_t pte_mkwrite(pte_t pte)
{
	pte_val(pte) |= _PAGE_WRITE;
	return pte;
}

static inline pte_t pte_mkdirty(pte_t pte)
{
	pte_val(pte) |= _PAGE_DIRTY;
	return pte;
}

static inline pte_t pte_mkyoung(pte_t pte)
{
	pte_val(pte) |= _PAGE_ACCESSED;
	return pte;
}

static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
	const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC;

	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
	return pte;
}

static inline int pmd_present(pmd_t pmd)
{
	return (pmd_val(pmd) != (unsigned long) invalid_pte_table)
			&& (pmd_val(pmd) != 0UL);
}

static inline void pmd_clear(pmd_t *pmdp)
{
	pmd_val(*pmdp) = (unsigned long) invalid_pte_table;
}

#define pte_pfn(pte)		(pte_val(pte) & 0xfffff)
#define pfn_pte(pfn, prot)	(__pte(pfn | pgprot_val(prot)))
#define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))

/*
 * Store a linux PTE into the linux page table.
 */
static inline void set_pte(pte_t *ptep, pte_t pteval)
{
	*ptep = pteval;
}

static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
			      pte_t *ptep, pte_t pteval)
{
	unsigned long paddr = (unsigned long)page_to_virt(pte_page(pteval));

	flush_dcache_range(paddr, paddr + PAGE_SIZE);
	set_pte(ptep, pteval);
}

static inline int pmd_none(pmd_t pmd)
{
	return (pmd_val(pmd) ==
		(unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL);
}

#define pmd_bad(pmd)	(pmd_val(pmd) & ~PAGE_MASK)

static inline void pte_clear(struct mm_struct *mm,
				unsigned long addr, pte_t *ptep)
{
	pte_t null;

	pte_val(null) = (addr >> PAGE_SHIFT) & 0xf;

	set_pte_at(mm, addr, ptep, null);
}

/*
 * Conversion functions: convert a page and protection to a page entry,
 * and a page entry and page directory to the page they refer to.
 */
#define mk_pte(page, prot)	(pfn_pte(page_to_pfn(page), prot))

/*
 * Conversion functions: convert a page and protection to a page entry,
 * and a page entry and page directory to the page they refer to.
 */
#define pmd_phys(pmd)		virt_to_phys((void *)pmd_val(pmd))
#define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))

static inline unsigned long pmd_page_vaddr(pmd_t pmd)
{
	return pmd_val(pmd);
}

#define pte_ERROR(e) \
	pr_err("%s:%d: bad pte %08lx.\n", \
		__FILE__, __LINE__, pte_val(e))
#define pgd_ERROR(e) \
	pr_err("%s:%d: bad pgd %08lx.\n", \
		__FILE__, __LINE__, pgd_val(e))

/*
 * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte):
 *
 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ...  1  0
 *  0  0  0  0 type.  0  0  0  0  0  0 offset.........
 *
 * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file.
 *
 * Note that the offset field is always non-zero, thus !pte_none(pte) is always
 * true.
 */
#define __swp_type(swp)		(((swp).val >> 26) & 0x3)
#define __swp_offset(swp)	((swp).val & 0xfffff)
#define __swp_entry(type, off)	((swp_entry_t) { (((type) & 0x3) << 26) \
						 | ((off) & 0xfffff) })
#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })

#define kern_addr_valid(addr)		(1)

extern void __init paging_init(void);
extern void __init mmu_init(void);

extern void update_mmu_cache(struct vm_area_struct *vma,
			     unsigned long address, pte_t *pte);

#endif /* _ASM_NIOS2_PGTABLE_H */