xref: /netbsd-src/sys/arch/amd64/include/pte.h (revision 7c3f385475147b6e1c4753f2bee961630e2dfc40)
1 /*	$NetBSD: pte.h,v 1.4 2008/04/16 21:51:03 cegger Exp $	*/
2 
3 /*
4  * Copyright (c) 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Frank van der Linden for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #ifndef _AMD64_PTE_H_
39 #define _AMD64_PTE_H_
40 
41 /*
42  * amd64 MMU hardware structure:
43  *
44  * the (first generation) amd64 MMU is a 4-level MMU which maps 2^48 bytes
45  * of  virtual memory. The  pagesize we use is is 4K (4096 [0x1000] bytes),
46  * although 2M and 4M can be used as well. The indexes in the levels
47  * are 9 bits wide (512 64bit entries per level), dividing the bits
48  * 9-9-9-9-12.
49  *
50  * The top level table, called PML4, contains 512 64bit entries pointing
51  * to 3rd level table. The 3rd level table is called the 'page directory
52  * pointers directory' and has 512 entries pointing to page directories.
53  * The 2nd level is the page directory, containing 512 pointers to
54  * page table pages. Lastly, level 1 consists of pages containing 512
55  * PTEs.
56  *
57  * Simply put, levels 4-1 all consist of pages containing 512
58  * entries pointing to the next level. Level 0 is the actual PTEs
59  * themselves.
60  *
61  * For a description on the other bits, which are i386 compatible,
62  * see the i386 pte.h
63  */
64 
65 #if !defined(_LOCORE)
66 
67 /*
68  * here we define the data types for PDEs and PTEs
69  */
70 
71 typedef uint64_t pd_entry_t;		/* PDE */
72 typedef uint64_t pt_entry_t;		/* PTE */
73 
74 #endif
75 
76 /*
77  * now we define various for playing with virtual addresses
78  */
79 
80 #define L1_SHIFT	12
81 #define	L2_SHIFT	21
82 #define	L3_SHIFT	30
83 #define	L4_SHIFT	39
84 #define	NBPD_L1		(1ULL << L1_SHIFT) /* # bytes mapped by L1 ent (4K) */
85 #define	NBPD_L2		(1ULL << L2_SHIFT) /* # bytes mapped by L2 ent (2MB) */
86 #define	NBPD_L3		(1ULL << L3_SHIFT) /* # bytes mapped by L3 ent (1G) */
87 #define	NBPD_L4		(1ULL << L4_SHIFT) /* # bytes mapped by L4 ent (512G) */
88 
89 #define L4_MASK		0x0000ff8000000000
90 #define L3_MASK		0x0000007fc0000000
91 #define L2_MASK		0x000000003fe00000
92 #define L1_MASK		0x00000000001ff000
93 
94 #define L4_FRAME	L4_MASK
95 #define L3_FRAME	(L4_FRAME|L3_MASK)
96 #define L2_FRAME	(L3_FRAME|L2_MASK)
97 #define L1_FRAME	(L2_FRAME|L1_MASK)
98 
99 /*
100  * PDE/PTE bits. These are no different from their i386 counterparts.
101  */
102 
103 #define	PG_V		0x0000000000000001	/* valid */
104 #define	PG_RO		0x0000000000000000	/* read-only */
105 #define	PG_RW		0x0000000000000002	/* read-write */
106 #define	PG_u		0x0000000000000004	/* user accessible */
107 #define	PG_PROT		0x0000000000000006
108 #define	PG_N		0x0000000000000018	/* non-cacheable */
109 #define	PG_U		0x0000000000000020	/* used */
110 #define	PG_M		0x0000000000000040	/* modified */
111 #define PG_PS		0x0000000000000080	/* 2MB page size */
112 #define PG_G		0x0000000000000100	/* not flushed */
113 #define PG_AVAIL1	0x0000000000000200
114 #define PG_AVAIL2	0x0000000000000400
115 #define PG_AVAIL3	0x0000000000000800
116 #define	PG_FRAME	0x000ffffffffff000
117 #define	PG_NX		0x8000000000000000
118 
119 #define	PG_LGFRAME	0x000fffffffe00000	/* large (2M) page frame mask */
120 
121 /*
122  * short forms of protection codes
123  */
124 
125 #define	PG_KR		0x0000000000000000	/* kernel read-only */
126 #define	PG_KW		0x0000000000000002	/* kernel read-write */
127 
128 /*
129  * page protection exception bits
130  */
131 
132 #define PGEX_P		0x01	/* protection violation (vs. no mapping) */
133 #define PGEX_W		0x02	/* exception during a write cycle */
134 #define PGEX_U		0x04	/* exception while in user mode (upl) */
135 #define PGEX_X		0x10	/* exception during instruction fetch */
136 
137 #endif /* _AMD64_PTE_H_ */
138