1 /*
2  *  linux/include/asm-arm/proc-armv/pgtable.h
3  *
4  *  Copyright (C) 1995-2001 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  *  12-Jan-1997	RMK	Altered flushing routines to use function pointers
11  *			now possible to combine ARM6, ARM7 and StrongARM versions.
12  *  17-Apr-1999	RMK	Now pass an area size to clean_cache_area and
13  *			flush_icache_area.
14  */
15 #ifndef __ASM_PROC_PGTABLE_H
16 #define __ASM_PROC_PGTABLE_H
17 
18 #include <asm/proc/domain.h>
19 #include <asm/arch/vmalloc.h>
20 
21 /*
22  * entries per page directory level: they are two-level, so
23  * we don't really have any PMD directory.
24  */
25 #define PTRS_PER_PTE		256
26 #define PTRS_PER_PMD		1
27 #define PTRS_PER_PGD		4096
28 
29 /****************
30 * PMD functions *
31 ****************/
32 
33 /* PMD types (actually level 1 descriptor) */
34 #define PMD_TYPE_MASK		0x0003
35 #define PMD_TYPE_FAULT		0x0000
36 #define PMD_TYPE_TABLE		0x0001
37 #define PMD_TYPE_SECT		0x0002
38 #define PMD_UPDATABLE		0x0010
39 #define PMD_SECT_CACHEABLE	0x0008
40 #define PMD_SECT_BUFFERABLE	0x0004
41 #define PMD_SECT_AP_WRITE	0x0400
42 #define PMD_SECT_AP_READ	0x0800
43 #define PMD_DOMAIN(x)		((x) << 5)
44 
45 #define _PAGE_USER_TABLE	(PMD_TYPE_TABLE | PMD_DOMAIN(DOMAIN_USER))
46 #define _PAGE_KERNEL_TABLE	(PMD_TYPE_TABLE | PMD_DOMAIN(DOMAIN_KERNEL))
47 
48 #define pmd_bad(pmd)		(pmd_val(pmd) & 2)
49 #define set_pmd(pmdp,pmd)	cpu_set_pmd(pmdp,pmd)
50 
__mk_pmd(pte_t * ptep,unsigned long prot)51 static inline pmd_t __mk_pmd(pte_t *ptep, unsigned long prot)
52 {
53 	unsigned long pte_ptr = (unsigned long)ptep;
54 	pmd_t pmd;
55 
56 	pte_ptr -= PTRS_PER_PTE * sizeof(void *);
57 
58 	/*
59 	 * The pmd must be loaded with the physical
60 	 * address of the PTE table
61 	 */
62 	pmd_val(pmd) = __virt_to_phys(pte_ptr) | prot;
63 
64 	return pmd;
65 }
66 
pmd_page(pmd_t pmd)67 static inline unsigned long pmd_page(pmd_t pmd)
68 {
69 	unsigned long ptr;
70 
71 	ptr = pmd_val(pmd) & ~(PTRS_PER_PTE * sizeof(void *) - 1);
72 
73 	ptr += PTRS_PER_PTE * sizeof(void *);
74 
75 	return __phys_to_virt(ptr);
76 }
77 
78 /****************
79 * PTE functions *
80 ****************/
81 
82 /* PTE types (actually level 2 descriptor) */
83 #define PTE_TYPE_MASK		0x0003
84 #define PTE_TYPE_FAULT		0x0000
85 #define PTE_TYPE_LARGE		0x0001
86 #define PTE_TYPE_SMALL		0x0002
87 #define PTE_AP_READ		0x0aa0
88 #define PTE_AP_WRITE		0x0550
89 #define PTE_CACHEABLE		0x0008
90 #define PTE_BUFFERABLE		0x0004
91 
92 #define set_pte(ptep, pte)	cpu_set_pte(ptep,pte)
93 
94 /* We now keep two sets of ptes - the physical and the linux version.
95  * This gives us many advantages, and allows us greater flexibility.
96  *
97  * The Linux pte's contain:
98  *  bit   meaning
99  *   0    page present
100  *   1    young
101  *   2    bufferable	- matches physical pte
102  *   3    cacheable	- matches physical pte
103  *   4    user
104  *   5    write
105  *   6    execute
106  *   7    dirty
107  *  8-11  unused
108  *  12-31 virtual page address
109  *
110  * These are stored at the pte pointer; the physical PTE is at -1024bytes
111  */
112 #define L_PTE_PRESENT		(1 << 0)
113 #define L_PTE_YOUNG		(1 << 1)
114 #define L_PTE_BUFFERABLE	(1 << 2)
115 #define L_PTE_CACHEABLE		(1 << 3)
116 #define L_PTE_USER		(1 << 4)
117 #define L_PTE_WRITE		(1 << 5)
118 #define L_PTE_EXEC		(1 << 6)
119 #define L_PTE_DIRTY		(1 << 7)
120 
121 /*
122  * The following macros handle the cache and bufferable bits...
123  */
124 #define _L_PTE_DEFAULT	L_PTE_PRESENT | L_PTE_YOUNG
125 #define _L_PTE_READ	L_PTE_USER | L_PTE_CACHEABLE | L_PTE_BUFFERABLE
126 
127 #define PAGE_NONE       __pgprot(_L_PTE_DEFAULT)
128 #define PAGE_COPY       __pgprot(_L_PTE_DEFAULT | _L_PTE_READ)
129 #define PAGE_SHARED     __pgprot(_L_PTE_DEFAULT | _L_PTE_READ | L_PTE_WRITE)
130 #define PAGE_READONLY   __pgprot(_L_PTE_DEFAULT | _L_PTE_READ)
131 #define PAGE_KERNEL     __pgprot(_L_PTE_DEFAULT | L_PTE_CACHEABLE | L_PTE_BUFFERABLE | L_PTE_DIRTY | L_PTE_WRITE)
132 
133 #define _PAGE_CHG_MASK	(PAGE_MASK | L_PTE_DIRTY | L_PTE_YOUNG)
134 
135 
136 /*
137  * The following only work if pte_present() is true.
138  * Undefined behaviour if not..
139  */
140 #define pte_present(pte)		(pte_val(pte) & L_PTE_PRESENT)
141 #define pte_read(pte)			(pte_val(pte) & L_PTE_USER)
142 #define pte_write(pte)			(pte_val(pte) & L_PTE_WRITE)
143 #define pte_exec(pte)			(pte_val(pte) & L_PTE_EXEC)
144 #define pte_dirty(pte)			(pte_val(pte) & L_PTE_DIRTY)
145 #define pte_young(pte)			(pte_val(pte) & L_PTE_YOUNG)
146 
147 #define PTE_BIT_FUNC(fn,op)			\
148 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
149 
150 /*PTE_BIT_FUNC(rdprotect, &= ~L_PTE_USER);*/
151 /*PTE_BIT_FUNC(mkread,    |= L_PTE_USER);*/
152 PTE_BIT_FUNC(wrprotect, &= ~L_PTE_WRITE);
153 PTE_BIT_FUNC(mkwrite,   |= L_PTE_WRITE);
154 PTE_BIT_FUNC(exprotect, &= ~L_PTE_EXEC);
155 PTE_BIT_FUNC(mkexec,    |= L_PTE_EXEC);
156 PTE_BIT_FUNC(mkclean,   &= ~L_PTE_DIRTY);
157 PTE_BIT_FUNC(mkdirty,   |= L_PTE_DIRTY);
158 PTE_BIT_FUNC(mkold,     &= ~L_PTE_YOUNG);
159 PTE_BIT_FUNC(mkyoung,   |= L_PTE_YOUNG);
160 
161 /*
162  * Mark the prot value as uncacheable and unbufferable.
163  */
164 #define pgprot_noncached(prot)	__pgprot(pgprot_val(prot) & ~(L_PTE_CACHEABLE | L_PTE_BUFFERABLE))
165 
166 #endif /* __ASM_PROC_PGTABLE_H */
167