xref: /openbmc/linux/arch/sh/include/asm/pgtable.h (revision bc5aa3a0)
1 /*
2  * This file contains the functions and defines necessary to modify and
3  * use the SuperH page table tree.
4  *
5  * Copyright (C) 1999 Niibe Yutaka
6  * Copyright (C) 2002 - 2007 Paul Mundt
7  *
8  * This file is subject to the terms and conditions of the GNU General
9  * Public License.  See the file "COPYING" in the main directory of this
10  * archive for more details.
11  */
12 #ifndef __ASM_SH_PGTABLE_H
13 #define __ASM_SH_PGTABLE_H
14 
15 #ifdef CONFIG_X2TLB
16 #include <asm/pgtable-3level.h>
17 #else
18 #include <asm/pgtable-2level.h>
19 #endif
20 #include <asm/page.h>
21 #include <asm/mmu.h>
22 
23 #ifndef __ASSEMBLY__
24 #include <asm/addrspace.h>
25 #include <asm/fixmap.h>
26 
27 /*
28  * ZERO_PAGE is a global shared page that is always zero: used
29  * for zero-mapped memory areas etc..
30  */
31 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
32 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
33 
34 #endif /* !__ASSEMBLY__ */
35 
36 /*
37  * Effective and physical address definitions, to aid with sign
38  * extension.
39  */
40 #define NEFF		32
41 #define	NEFF_SIGN	(1LL << (NEFF - 1))
42 #define	NEFF_MASK	(-1LL << NEFF)
43 
44 static inline unsigned long long neff_sign_extend(unsigned long val)
45 {
46 	unsigned long long extended = val;
47 	return (extended & NEFF_SIGN) ? (extended | NEFF_MASK) : extended;
48 }
49 
50 #ifdef CONFIG_29BIT
51 #define NPHYS		29
52 #else
53 #define NPHYS		32
54 #endif
55 
56 #define	NPHYS_SIGN	(1LL << (NPHYS - 1))
57 #define	NPHYS_MASK	(-1LL << NPHYS)
58 
59 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
60 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
61 
62 /* Entries per level */
63 #define PTRS_PER_PTE	(PAGE_SIZE / (1 << PTE_MAGNITUDE))
64 
65 #define FIRST_USER_ADDRESS	0UL
66 
67 #define PHYS_ADDR_MASK29		0x1fffffff
68 #define PHYS_ADDR_MASK32		0xffffffff
69 
70 static inline unsigned long phys_addr_mask(void)
71 {
72 	/* Is the MMU in 29bit mode? */
73 	if (__in_29bit_mode())
74 		return PHYS_ADDR_MASK29;
75 
76 	return PHYS_ADDR_MASK32;
77 }
78 
79 #define PTE_PHYS_MASK		(phys_addr_mask() & PAGE_MASK)
80 #define PTE_FLAGS_MASK		(~(PTE_PHYS_MASK) << PAGE_SHIFT)
81 
82 #ifdef CONFIG_SUPERH32
83 #define VMALLOC_START	(P3SEG)
84 #else
85 #define VMALLOC_START	(0xf0000000)
86 #endif
87 #define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
88 
89 #if defined(CONFIG_SUPERH32)
90 #include <asm/pgtable_32.h>
91 #else
92 #include <asm/pgtable_64.h>
93 #endif
94 
95 /*
96  * SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
97  * protection for execute, and considers it the same as a read. Also, write
98  * permission implies read permission. This is the closest we can get..
99  *
100  * SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
101  * not only supporting separate execute, read, and write bits, but having
102  * completely separate permission bits for user and kernel space.
103  */
104 	 /*xwr*/
105 #define __P000	PAGE_NONE
106 #define __P001	PAGE_READONLY
107 #define __P010	PAGE_COPY
108 #define __P011	PAGE_COPY
109 #define __P100	PAGE_EXECREAD
110 #define __P101	PAGE_EXECREAD
111 #define __P110	PAGE_COPY
112 #define __P111	PAGE_COPY
113 
114 #define __S000	PAGE_NONE
115 #define __S001	PAGE_READONLY
116 #define __S010	PAGE_WRITEONLY
117 #define __S011	PAGE_SHARED
118 #define __S100	PAGE_EXECREAD
119 #define __S101	PAGE_EXECREAD
120 #define __S110	PAGE_RWX
121 #define __S111	PAGE_RWX
122 
123 typedef pte_t *pte_addr_t;
124 
125 #define kern_addr_valid(addr)	(1)
126 
127 #define pte_pfn(x)		((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
128 
129 /*
130  * Initialise the page table caches
131  */
132 extern void pgtable_cache_init(void);
133 
134 struct vm_area_struct;
135 struct mm_struct;
136 
137 extern void __update_cache(struct vm_area_struct *vma,
138 			   unsigned long address, pte_t pte);
139 extern void __update_tlb(struct vm_area_struct *vma,
140 			 unsigned long address, pte_t pte);
141 
142 static inline void
143 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
144 {
145 	pte_t pte = *ptep;
146 	__update_cache(vma, address, pte);
147 	__update_tlb(vma, address, pte);
148 }
149 
150 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
151 extern void paging_init(void);
152 extern void page_table_range_init(unsigned long start, unsigned long end,
153 				  pgd_t *pgd);
154 
155 /* arch/sh/mm/mmap.c */
156 #define HAVE_ARCH_UNMAPPED_AREA
157 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
158 
159 #define __HAVE_ARCH_PTE_SPECIAL
160 
161 #include <asm-generic/pgtable.h>
162 
163 #endif /* __ASM_SH_PGTABLE_H */
164