xref: /openbmc/linux/arch/sh/include/asm/pgtable.h (revision 93dc544c)
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 #include <asm-generic/pgtable-nopmd.h>
16 #include <asm/page.h>
17 
18 #ifndef __ASSEMBLY__
19 #include <asm/addrspace.h>
20 #include <asm/fixmap.h>
21 
22 /*
23  * ZERO_PAGE is a global shared page that is always zero: used
24  * for zero-mapped memory areas etc..
25  */
26 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
27 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
28 
29 #endif /* !__ASSEMBLY__ */
30 
31 /*
32  * Effective and physical address definitions, to aid with sign
33  * extension.
34  */
35 #define NEFF		32
36 #define	NEFF_SIGN	(1LL << (NEFF - 1))
37 #define	NEFF_MASK	(-1LL << NEFF)
38 
39 #ifdef CONFIG_29BIT
40 #define NPHYS		29
41 #else
42 #define NPHYS		32
43 #endif
44 
45 #define	NPHYS_SIGN	(1LL << (NPHYS - 1))
46 #define	NPHYS_MASK	(-1LL << NPHYS)
47 
48 /*
49  * traditional two-level paging structure
50  */
51 /* PTE bits */
52 #if defined(CONFIG_X2TLB) || defined(CONFIG_SUPERH64)
53 # define PTE_MAGNITUDE	3	/* 64-bit PTEs on extended mode SH-X2 TLB */
54 #else
55 # define PTE_MAGNITUDE	2	/* 32-bit PTEs */
56 #endif
57 #define PTE_SHIFT	PAGE_SHIFT
58 #define PTE_BITS	(PTE_SHIFT - PTE_MAGNITUDE)
59 
60 /* PGD bits */
61 #define PGDIR_SHIFT	(PTE_SHIFT + PTE_BITS)
62 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
63 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
64 
65 /* Entries per level */
66 #define PTRS_PER_PTE	(PAGE_SIZE / (1 << PTE_MAGNITUDE))
67 #define PTRS_PER_PGD	(PAGE_SIZE / sizeof(pgd_t))
68 
69 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
70 #define FIRST_USER_ADDRESS	0
71 
72 #ifdef CONFIG_32BIT
73 #define PHYS_ADDR_MASK		0xffffffff
74 #else
75 #define PHYS_ADDR_MASK		0x1fffffff
76 #endif
77 
78 #define PTE_PHYS_MASK		(PHYS_ADDR_MASK & PAGE_MASK)
79 
80 #ifdef CONFIG_SUPERH32
81 #define VMALLOC_START	(P3SEG)
82 #else
83 #define VMALLOC_START	(0xf0000000)
84 #endif
85 #define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
86 
87 #if defined(CONFIG_SUPERH32)
88 #include <asm/pgtable_32.h>
89 #else
90 #include <asm/pgtable_64.h>
91 #endif
92 
93 /*
94  * SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
95  * protection for execute, and considers it the same as a read. Also, write
96  * permission implies read permission. This is the closest we can get..
97  *
98  * SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
99  * not only supporting separate execute, read, and write bits, but having
100  * completely separate permission bits for user and kernel space.
101  */
102 	 /*xwr*/
103 #define __P000	PAGE_NONE
104 #define __P001	PAGE_READONLY
105 #define __P010	PAGE_COPY
106 #define __P011	PAGE_COPY
107 #define __P100	PAGE_EXECREAD
108 #define __P101	PAGE_EXECREAD
109 #define __P110	PAGE_COPY
110 #define __P111	PAGE_COPY
111 
112 #define __S000	PAGE_NONE
113 #define __S001	PAGE_READONLY
114 #define __S010	PAGE_WRITEONLY
115 #define __S011	PAGE_SHARED
116 #define __S100	PAGE_EXECREAD
117 #define __S101	PAGE_EXECREAD
118 #define __S110	PAGE_RWX
119 #define __S111	PAGE_RWX
120 
121 typedef pte_t *pte_addr_t;
122 
123 #define kern_addr_valid(addr)	(1)
124 
125 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot)		\
126 		remap_pfn_range(vma, vaddr, pfn, size, prot)
127 
128 #define pte_pfn(x)		((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
129 
130 /*
131  * No page table caches to initialise
132  */
133 #define pgtable_cache_init()	do { } while (0)
134 
135 #if !defined(CONFIG_CACHE_OFF) && (defined(CONFIG_CPU_SH4) || \
136 	defined(CONFIG_SH7705_CACHE_32KB))
137 struct mm_struct;
138 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
139 pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
140 #endif
141 
142 struct vm_area_struct;
143 extern void update_mmu_cache(struct vm_area_struct * vma,
144 			     unsigned long address, pte_t pte);
145 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
146 extern void paging_init(void);
147 extern void page_table_range_init(unsigned long start, unsigned long end,
148 				  pgd_t *pgd);
149 
150 #include <asm-generic/pgtable.h>
151 
152 #endif /* __ASM_SH_PGTABLE_H */
153