1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
8 */
9#ifndef _ASM_PGTABLE_32_H
10#define _ASM_PGTABLE_32_H
11
12#include <asm/addrspace.h>
13#include <asm/page.h>
14
15#include <linux/linkage.h>
16#include <asm/cachectl.h>
17#include <asm/fixmap.h>
18
19#include <asm-generic/pgtable-nopmd.h>
20
21/*
22 * Basically we have the same two-level (which is the logical three level
23 * Linux page table layout folded) page tables as the i386.  Some day
24 * when we have proper page coloring support we can have a 1% quicker
25 * tlb refill handling mechanism, but for now it is a bit slower but
26 * works even with the cache aliasing problem the R4k and above have.
27 */
28
29/* PGDIR_SHIFT determines what a third-level page table entry can map */
30#define PGDIR_SHIFT	(2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2)
31#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
32#define PGDIR_MASK	(~(PGDIR_SIZE-1))
33
34/*
35 * Entries per page directory level: we use two-level, so
36 * we don't really have any PUD/PMD directory physically.
37 */
38#define __PGD_ORDER	(32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2)
39#define PGD_ORDER	(__PGD_ORDER >= 0 ? __PGD_ORDER : 0)
40#define PUD_ORDER	aieeee_attempt_to_allocate_pud
41#define PMD_ORDER	1
42#define PTE_ORDER	0
43
44#define PTRS_PER_PGD	(USER_PTRS_PER_PGD * 2)
45#define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
46
47#define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
48#define FIRST_USER_ADDRESS	0
49
50#define VMALLOC_START     MAP_BASE
51
52#define PKMAP_BASE		(0xfe000000UL)
53
54#ifdef CONFIG_HIGHMEM
55# define VMALLOC_END	(PKMAP_BASE-2*PAGE_SIZE)
56#else
57# define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
58#endif
59
60#ifdef CONFIG_64BIT_PHYS_ADDR
61#define pte_ERROR(e) \
62	printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e))
63#else
64#define pte_ERROR(e) \
65	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
66#endif
67#define pgd_ERROR(e) \
68	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
69
70extern void load_pgd(unsigned long pg_dir);
71
72extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
73
74/*
75 * Empty pgd/pmd entries point to the invalid_pte_table.
76 */
77static inline int pmd_none(pmd_t pmd)
78{
79	return pmd_val(pmd) == (unsigned long) invalid_pte_table;
80}
81
82#define pmd_bad(pmd)		(pmd_val(pmd) & ~PAGE_MASK)
83
84static inline int pmd_present(pmd_t pmd)
85{
86	return pmd_val(pmd) != (unsigned long) invalid_pte_table;
87}
88
89static inline void pmd_clear(pmd_t *pmdp)
90{
91	pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
92}
93
94#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
95#define pte_page(x)		pfn_to_page(pte_pfn(x))
96#define pte_pfn(x)		((unsigned long)((x).pte_high >> 6))
97static inline pte_t
98pfn_pte(unsigned long pfn, pgprot_t prot)
99{
100	pte_t pte;
101	pte.pte_high = (pfn << 6) | (pgprot_val(prot) & 0x3f);
102	pte.pte_low = pgprot_val(prot);
103	return pte;
104}
105
106#else
107
108#define pte_page(x)		pfn_to_page(pte_pfn(x))
109
110#ifdef CONFIG_CPU_VR41XX
111#define pte_pfn(x)		((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
112#define pfn_pte(pfn, prot)	__pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
113#else
114#define pte_pfn(x)		((unsigned long)((x).pte >> _PFN_SHIFT))
115#define pfn_pte(pfn, prot)	__pte(((unsigned long long)(pfn) << _PFN_SHIFT) | pgprot_val(prot))
116#endif
117#endif /* defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) */
118
119#define __pgd_offset(address)	pgd_index(address)
120#define __pud_offset(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
121#define __pmd_offset(address)	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
122
123/* to find an entry in a kernel page-table-directory */
124#define pgd_offset_k(address) pgd_offset(&init_mm, address)
125
126#define pgd_index(address)	(((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
127
128/* to find an entry in a page-table-directory */
129#define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
130
131/* Find an entry in the third-level page table.. */
132#define __pte_offset(address)						\
133	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
134#define pte_offset(dir, address)					\
135	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
136#define pte_offset_kernel(dir, address)					\
137	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
138
139#define pte_offset_map(dir, address)                                    \
140	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
141#define pte_unmap(pte) ((void)(pte))
142
143#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
144
145/* Swap entries must have VALID bit cleared. */
146#define __swp_type(x)		(((x).val >> 10) & 0x1f)
147#define __swp_offset(x)		((x).val >> 15)
148#define __swp_entry(type,offset)	\
149	((swp_entry_t) { ((type) << 10) | ((offset) << 15) })
150
151/*
152 * Bits 0, 4, 8, and 9 are taken, split up 28 bits of offset into this range:
153 */
154#define PTE_FILE_MAX_BITS	28
155
156#define pte_to_pgoff(_pte)	((((_pte).pte >> 1 ) & 0x07) | \
157				 (((_pte).pte >> 2 ) & 0x38) | \
158				 (((_pte).pte >> 10) <<  6 ))
159
160#define pgoff_to_pte(off)	((pte_t) { (((off) & 0x07) << 1 ) | \
161					   (((off) & 0x38) << 2 ) | \
162					   (((off) >>  6 ) << 10) | \
163					   _PAGE_FILE })
164
165#else
166
167/* Swap entries must have VALID and GLOBAL bits cleared. */
168#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
169#define __swp_type(x)		(((x).val >> 2) & 0x1f)
170#define __swp_offset(x) 	 ((x).val >> 7)
171#define __swp_entry(type,offset)	\
172		((swp_entry_t)  { ((type) << 2) | ((offset) << 7) })
173#else
174#define __swp_type(x)		(((x).val >> 8) & 0x1f)
175#define __swp_offset(x) 	 ((x).val >> 13)
176#define __swp_entry(type,offset)	\
177		((swp_entry_t)  { ((type) << 8) | ((offset) << 13) })
178#endif /* defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) */
179
180#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
181/*
182 * Bits 0 and 1 of pte_high are taken, use the rest for the page offset...
183 */
184#define PTE_FILE_MAX_BITS	30
185
186#define pte_to_pgoff(_pte)	((_pte).pte_high >> 2)
187#define pgoff_to_pte(off) 	((pte_t) { _PAGE_FILE, (off) << 2 })
188
189#else
190/*
191 * Bits 0, 4, 6, and 7 are taken, split up 28 bits of offset into this range:
192 */
193#define PTE_FILE_MAX_BITS	28
194
195#define pte_to_pgoff(_pte)	((((_pte).pte >> 1) & 0x7) | \
196				 (((_pte).pte >> 2) & 0x8) | \
197				 (((_pte).pte >> 8) <<  4))
198
199#define pgoff_to_pte(off)	((pte_t) { (((off) & 0x7) << 1) | \
200					   (((off) & 0x8) << 2) | \
201					   (((off) >>  4) << 8) | \
202					   _PAGE_FILE })
203#endif
204
205#endif
206
207#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
208#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_high })
209#define __swp_entry_to_pte(x)	((pte_t) { 0, (x).val })
210#else
211#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
212#define __swp_entry_to_pte(x)	((pte_t) { (x).val })
213#endif
214
215#endif /* _ASM_PGTABLE_32_H */
216