xref: /openbmc/linux/arch/mips/include/asm/pgtable-32.h (revision 9cfc5c90)
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 extern int temp_tlb_entry;
22 
23 /*
24  * - add_temporary_entry() add a temporary TLB entry. We use TLB entries
25  *	starting at the top and working down. This is for populating the
26  *	TLB before trap_init() puts the TLB miss handler in place. It
27  *	should be used only for entries matching the actual page tables,
28  *	to prevent inconsistencies.
29  */
30 extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
31 			       unsigned long entryhi, unsigned long pagemask);
32 
33 /*
34  * Basically we have the same two-level (which is the logical three level
35  * Linux page table layout folded) page tables as the i386.  Some day
36  * when we have proper page coloring support we can have a 1% quicker
37  * tlb refill handling mechanism, but for now it is a bit slower but
38  * works even with the cache aliasing problem the R4k and above have.
39  */
40 
41 /* PGDIR_SHIFT determines what a third-level page table entry can map */
42 #define PGDIR_SHIFT	(2 * PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2)
43 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
44 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
45 
46 /*
47  * Entries per page directory level: we use two-level, so
48  * we don't really have any PUD/PMD directory physically.
49  */
50 #define __PGD_ORDER	(32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2)
51 #define PGD_ORDER	(__PGD_ORDER >= 0 ? __PGD_ORDER : 0)
52 #define PUD_ORDER	aieeee_attempt_to_allocate_pud
53 #define PMD_ORDER	1
54 #define PTE_ORDER	0
55 
56 #define PTRS_PER_PGD	(USER_PTRS_PER_PGD * 2)
57 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
58 
59 #define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
60 #define FIRST_USER_ADDRESS	0UL
61 
62 #define VMALLOC_START	  MAP_BASE
63 
64 #define PKMAP_BASE		(0xfe000000UL)
65 
66 #ifdef CONFIG_HIGHMEM
67 # define VMALLOC_END	(PKMAP_BASE-2*PAGE_SIZE)
68 #else
69 # define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
70 #endif
71 
72 #ifdef CONFIG_PHYS_ADDR_T_64BIT
73 #define pte_ERROR(e) \
74 	printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e))
75 #else
76 #define pte_ERROR(e) \
77 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
78 #endif
79 #define pgd_ERROR(e) \
80 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
81 
82 extern void load_pgd(unsigned long pg_dir);
83 
84 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
85 
86 /*
87  * Empty pgd/pmd entries point to the invalid_pte_table.
88  */
89 static inline int pmd_none(pmd_t pmd)
90 {
91 	return pmd_val(pmd) == (unsigned long) invalid_pte_table;
92 }
93 
94 #define pmd_bad(pmd)		(pmd_val(pmd) & ~PAGE_MASK)
95 
96 static inline int pmd_present(pmd_t pmd)
97 {
98 	return pmd_val(pmd) != (unsigned long) invalid_pte_table;
99 }
100 
101 static inline void pmd_clear(pmd_t *pmdp)
102 {
103 	pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
104 }
105 
106 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
107 #define pte_page(x)		pfn_to_page(pte_pfn(x))
108 #define pte_pfn(x)		(((unsigned long)((x).pte_high >> _PFN_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT))
109 static inline pte_t
110 pfn_pte(unsigned long pfn, pgprot_t prot)
111 {
112 	pte_t pte;
113 
114 	pte.pte_low = (pfn >> _PAGE_PRESENT_SHIFT) |
115 				(pgprot_val(prot) & ~_PFNX_MASK);
116 	pte.pte_high = (pfn << _PFN_SHIFT) |
117 				(pgprot_val(prot) & ~_PFN_MASK);
118 	return pte;
119 }
120 
121 #else
122 
123 #define pte_page(x)		pfn_to_page(pte_pfn(x))
124 
125 #ifdef CONFIG_CPU_VR41XX
126 #define pte_pfn(x)		((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
127 #define pfn_pte(pfn, prot)	__pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
128 #else
129 #define pte_pfn(x)		((unsigned long)((x).pte >> _PFN_SHIFT))
130 #define pfn_pte(pfn, prot)	__pte(((unsigned long long)(pfn) << _PFN_SHIFT) | pgprot_val(prot))
131 #endif
132 #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */
133 
134 #define __pgd_offset(address)	pgd_index(address)
135 #define __pud_offset(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
136 #define __pmd_offset(address)	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
137 
138 /* to find an entry in a kernel page-table-directory */
139 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
140 
141 #define pgd_index(address)	(((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
142 
143 /* to find an entry in a page-table-directory */
144 #define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
145 
146 /* Find an entry in the third-level page table.. */
147 #define __pte_offset(address)						\
148 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
149 #define pte_offset(dir, address)					\
150 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
151 #define pte_offset_kernel(dir, address)					\
152 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
153 
154 #define pte_offset_map(dir, address)					\
155 	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
156 #define pte_unmap(pte) ((void)(pte))
157 
158 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
159 
160 /* Swap entries must have VALID bit cleared. */
161 #define __swp_type(x)			(((x).val >> 10) & 0x1f)
162 #define __swp_offset(x)			((x).val >> 15)
163 #define __swp_entry(type,offset)	((swp_entry_t) { ((type) << 10) | ((offset) << 15) })
164 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
165 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
166 
167 #else
168 
169 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
170 
171 /* Swap entries must have VALID and GLOBAL bits cleared. */
172 #define __swp_type(x)			(((x).val >> 4) & 0x1f)
173 #define __swp_offset(x)			 ((x).val >> 9)
174 #define __swp_entry(type,offset)	((swp_entry_t)  { ((type) << 4) | ((offset) << 9) })
175 #define __pte_to_swp_entry(pte)		((swp_entry_t) { (pte).pte_high })
176 #define __swp_entry_to_pte(x)		((pte_t) { 0, (x).val })
177 
178 #else
179 /*
180  * Constraints:
181  *      _PAGE_PRESENT at bit 0
182  *      _PAGE_MODIFIED at bit 4
183  *      _PAGE_GLOBAL at bit 6
184  *      _PAGE_VALID at bit 7
185  */
186 #define __swp_type(x)			(((x).val >> 8) & 0x1f)
187 #define __swp_offset(x)			 ((x).val >> 13)
188 #define __swp_entry(type,offset)	((swp_entry_t)	{ ((type) << 8) | ((offset) << 13) })
189 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
190 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
191 
192 #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */
193 
194 #endif /* defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) */
195 
196 #endif /* _ASM_PGTABLE_32_H */
197