xref: /linux/arch/mips/include/asm/pgtable-32.h (revision 44f57d78)
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 #define __ARCH_USE_5LEVEL_HACK
20 #include <asm-generic/pgtable-nopmd.h>
21 
22 #ifdef CONFIG_HIGHMEM
23 #include <asm/highmem.h>
24 #endif
25 
26 extern int temp_tlb_entry;
27 
28 /*
29  * - add_temporary_entry() add a temporary TLB entry. We use TLB entries
30  *	starting at the top and working down. This is for populating the
31  *	TLB before trap_init() puts the TLB miss handler in place. It
32  *	should be used only for entries matching the actual page tables,
33  *	to prevent inconsistencies.
34  */
35 extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
36 			       unsigned long entryhi, unsigned long pagemask);
37 
38 /*
39  * Basically we have the same two-level (which is the logical three level
40  * Linux page table layout folded) page tables as the i386.  Some day
41  * when we have proper page coloring support we can have a 1% quicker
42  * tlb refill handling mechanism, but for now it is a bit slower but
43  * works even with the cache aliasing problem the R4k and above have.
44  */
45 
46 /* PGDIR_SHIFT determines what a third-level page table entry can map */
47 #define PGDIR_SHIFT	(2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2)
48 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
49 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
50 
51 /*
52  * Entries per page directory level: we use two-level, so
53  * we don't really have any PUD/PMD directory physically.
54  */
55 #define __PGD_ORDER	(32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2)
56 #define PGD_ORDER	(__PGD_ORDER >= 0 ? __PGD_ORDER : 0)
57 #define PUD_ORDER	aieeee_attempt_to_allocate_pud
58 #define PMD_ORDER	1
59 #define PTE_ORDER	0
60 
61 #define PTRS_PER_PGD	(USER_PTRS_PER_PGD * 2)
62 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
63 
64 #define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
65 #define FIRST_USER_ADDRESS	0UL
66 
67 #define VMALLOC_START	  MAP_BASE
68 
69 #define PKMAP_END	((FIXADDR_START) & ~((LAST_PKMAP << PAGE_SHIFT)-1))
70 #define PKMAP_BASE	(PKMAP_END - PAGE_SIZE * LAST_PKMAP)
71 
72 #ifdef CONFIG_HIGHMEM
73 # define VMALLOC_END	(PKMAP_BASE-2*PAGE_SIZE)
74 #else
75 # define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
76 #endif
77 
78 #ifdef CONFIG_PHYS_ADDR_T_64BIT
79 #define pte_ERROR(e) \
80 	printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e))
81 #else
82 #define pte_ERROR(e) \
83 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
84 #endif
85 #define pgd_ERROR(e) \
86 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
87 
88 extern void load_pgd(unsigned long pg_dir);
89 
90 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
91 
92 /*
93  * Empty pgd/pmd entries point to the invalid_pte_table.
94  */
95 static inline int pmd_none(pmd_t pmd)
96 {
97 	return pmd_val(pmd) == (unsigned long) invalid_pte_table;
98 }
99 
100 #define pmd_bad(pmd)		(pmd_val(pmd) & ~PAGE_MASK)
101 
102 static inline int pmd_present(pmd_t pmd)
103 {
104 	return pmd_val(pmd) != (unsigned long) invalid_pte_table;
105 }
106 
107 static inline void pmd_clear(pmd_t *pmdp)
108 {
109 	pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
110 }
111 
112 #if defined(CONFIG_XPA)
113 
114 #define pte_pfn(x)		(((unsigned long)((x).pte_high >> _PFN_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT))
115 static inline pte_t
116 pfn_pte(unsigned long pfn, pgprot_t prot)
117 {
118 	pte_t pte;
119 
120 	pte.pte_low = (pfn >> _PAGE_PRESENT_SHIFT) |
121 				(pgprot_val(prot) & ~_PFNX_MASK);
122 	pte.pte_high = (pfn << _PFN_SHIFT) |
123 				(pgprot_val(prot) & ~_PFN_MASK);
124 	return pte;
125 }
126 
127 #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
128 
129 #define pte_pfn(x)		((unsigned long)((x).pte_high >> 6))
130 
131 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
132 {
133 	pte_t pte;
134 
135 	pte.pte_high = (pfn << 6) | (pgprot_val(prot) & 0x3f);
136 	pte.pte_low = pgprot_val(prot);
137 
138 	return pte;
139 }
140 
141 #else
142 
143 #ifdef CONFIG_CPU_VR41XX
144 #define pte_pfn(x)		((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
145 #define pfn_pte(pfn, prot)	__pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
146 #else
147 #define pte_pfn(x)		((unsigned long)((x).pte >> _PFN_SHIFT))
148 #define pfn_pte(pfn, prot)	__pte(((unsigned long long)(pfn) << _PFN_SHIFT) | pgprot_val(prot))
149 #endif
150 #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */
151 
152 #define pte_page(x)		pfn_to_page(pte_pfn(x))
153 
154 #define __pgd_offset(address)	pgd_index(address)
155 #define __pud_offset(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
156 #define __pmd_offset(address)	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
157 
158 /* to find an entry in a kernel page-table-directory */
159 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
160 
161 #define pgd_index(address)	(((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
162 
163 /* to find an entry in a page-table-directory */
164 #define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
165 
166 /* Find an entry in the third-level page table.. */
167 #define __pte_offset(address)						\
168 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
169 #define pte_offset(dir, address)					\
170 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
171 #define pte_offset_kernel(dir, address)					\
172 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
173 
174 #define pte_offset_map(dir, address)					\
175 	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
176 #define pte_unmap(pte) ((void)(pte))
177 
178 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
179 
180 /* Swap entries must have VALID bit cleared. */
181 #define __swp_type(x)			(((x).val >> 10) & 0x1f)
182 #define __swp_offset(x)			((x).val >> 15)
183 #define __swp_entry(type,offset)	((swp_entry_t) { ((type) << 10) | ((offset) << 15) })
184 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
185 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
186 
187 #else
188 
189 #if defined(CONFIG_XPA)
190 
191 /* Swap entries must have VALID and GLOBAL bits cleared. */
192 #define __swp_type(x)			(((x).val >> 4) & 0x1f)
193 #define __swp_offset(x)			 ((x).val >> 9)
194 #define __swp_entry(type,offset)	((swp_entry_t)  { ((type) << 4) | ((offset) << 9) })
195 #define __pte_to_swp_entry(pte)		((swp_entry_t) { (pte).pte_high })
196 #define __swp_entry_to_pte(x)		((pte_t) { 0, (x).val })
197 
198 #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
199 
200 /* Swap entries must have VALID and GLOBAL bits cleared. */
201 #define __swp_type(x)			(((x).val >> 2) & 0x1f)
202 #define __swp_offset(x)			 ((x).val >> 7)
203 #define __swp_entry(type, offset)	((swp_entry_t)  { ((type) << 2) | ((offset) << 7) })
204 #define __pte_to_swp_entry(pte)		((swp_entry_t) { (pte).pte_high })
205 #define __swp_entry_to_pte(x)		((pte_t) { 0, (x).val })
206 
207 #else
208 /*
209  * Constraints:
210  *      _PAGE_PRESENT at bit 0
211  *      _PAGE_MODIFIED at bit 4
212  *      _PAGE_GLOBAL at bit 6
213  *      _PAGE_VALID at bit 7
214  */
215 #define __swp_type(x)			(((x).val >> 8) & 0x1f)
216 #define __swp_offset(x)			 ((x).val >> 13)
217 #define __swp_entry(type,offset)	((swp_entry_t)	{ ((type) << 8) | ((offset) << 13) })
218 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
219 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
220 
221 #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */
222 
223 #endif /* defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) */
224 
225 #endif /* _ASM_PGTABLE_32_H */
226