xref: /netbsd-src/sys/arch/arm/include/arm32/pte.h (revision f648d12d47727113ad5330b0753bb2f2ef8e1045)
1 /*	$NetBSD: pte.h,v 1.7 2003/05/21 18:04:43 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe 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 _ARM_PTE_H_
39 #define	_ARM_PTE_H_
40 
41 /*
42  * The ARM MMU architecture was introduced with ARM v3 (previous ARM
43  * architecture versions used an optional off-CPU memory controller
44  * to perform address translation).
45  *
46  * The ARM MMU consists of a TLB and translation table walking logic.
47  * There is typically one TLB per memory interface (or, put another
48  * way, one TLB per software-visible cache).
49  *
50  * The ARM MMU is capable of mapping memory in the following chunks:
51  *
52  *	1M	Sections (L1 table)
53  *
54  *	64K	Large Pages (L2 table)
55  *
56  *	4K	Small Pages (L2 table)
57  *
58  *	1K	Tiny Pages (L2 table)
59  *
60  * There are two types of L2 tables: Coarse Tables and Fine Tables.
61  * Coarse Tables can map Large and Small Pages.  Fine Tables can
62  * map Tiny Pages.
63  *
64  * Coarse Tables can define 4 Subpages within Large and Small pages.
65  * Subpages define different permissions for each Subpage within
66  * a Page.
67  *
68  * Coarse Tables are 1K in length.  Fine tables are 4K in length.
69  *
70  * The Translation Table Base register holds the pointer to the
71  * L1 Table.  The L1 Table is a 16K contiguous chunk of memory
72  * aligned to a 16K boundary.  Each entry in the L1 Table maps
73  * 1M of virtual address space, either via a Section mapping or
74  * via an L2 Table.
75  *
76  * In addition, the Fast Context Switching Extension (FCSE) is available
77  * on some ARM v4 and ARM v5 processors.  FCSE is a way of eliminating
78  * TLB/cache flushes on context switch by use of a smaller address space
79  * and a "process ID" that modifies the virtual address before being
80  * presented to the translation logic.
81  */
82 
83 #ifndef _LOCORE
84 typedef uint32_t	pd_entry_t;	/* L1 table entry */
85 typedef uint32_t	pt_entry_t;	/* L2 table entry */
86 #endif /* _LOCORE */
87 
88 #define	L1_S_SIZE	0x00100000	/* 1M */
89 #define	L1_S_OFFSET	(L1_S_SIZE - 1)
90 #define	L1_S_FRAME	(~L1_S_OFFSET)
91 #define	L1_S_SHIFT	20
92 
93 #define	L2_L_SIZE	0x00010000	/* 64K */
94 #define	L2_L_OFFSET	(L2_L_SIZE - 1)
95 #define	L2_L_FRAME	(~L2_L_OFFSET)
96 #define	L2_L_SHIFT	16
97 
98 #define	L2_S_SIZE	0x00001000	/* 4K */
99 #define	L2_S_OFFSET	(L2_S_SIZE - 1)
100 #define	L2_S_FRAME	(~L2_S_OFFSET)
101 #define	L2_S_SHIFT	12
102 
103 #define	L2_T_SIZE	0x00000400	/* 1K */
104 #define	L2_T_OFFSET	(L2_T_SIZE - 1)
105 #define	L2_T_FRAME	(~L2_T_OFFSET)
106 #define	L2_T_SHIFT	10
107 
108 /*
109  * The NetBSD VM implementation only works on whole pages (4K),
110  * whereas the ARM MMU's Coarse tables are sized in terms of 1K
111  * (16K L1 table, 1K L2 table).
112  *
113  * So, we allocate L2 tables 4 at a time, thus yielding a 4K L2
114  * table.
115  */
116 #define	L1_ADDR_BITS	0xfff00000	/* L1 PTE address bits */
117 #define	L2_ADDR_BITS	0x000ff000	/* L2 PTE address bits */
118 
119 #define	L1_TABLE_SIZE	0x4000		/* 16K */
120 #define	L2_TABLE_SIZE	0x1000		/* 4K */
121 /*
122  * The new pmap deals with the 1KB coarse L2 tables by
123  * allocating them from a pool. Until every port has been converted,
124  * keep the old L2_TABLE_SIZE define lying around. Converted ports
125  * should use L2_TABLE_SIZE_REAL until then.
126  */
127 #define	L2_TABLE_SIZE_REAL	0x400	/* 1K */
128 
129 /*
130  * ARM L1 Descriptors
131  */
132 
133 #define	L1_TYPE_INV	0x00		/* Invalid (fault) */
134 #define	L1_TYPE_C	0x01		/* Coarse L2 */
135 #define	L1_TYPE_S	0x02		/* Section */
136 #define	L1_TYPE_F	0x03		/* Fine L2 */
137 #define	L1_TYPE_MASK	0x03		/* mask of type bits */
138 
139 /* L1 Section Descriptor */
140 #define	L1_S_B		0x00000004	/* bufferable Section */
141 #define	L1_S_C		0x00000008	/* cacheable Section */
142 #define	L1_S_IMP	0x00000010	/* implementation defined */
143 #define	L1_S_DOM(x)	((x) << 5)	/* domain */
144 #define	L1_S_DOM_MASK	L1_S_DOM(0xf)
145 #define	L1_S_AP(x)	((x) << 10)	/* access permissions */
146 #define	L1_S_ADDR_MASK	0xfff00000	/* phys address of section */
147 
148 #define	L1_S_XSCALE_P	0x00000200	/* ECC enable for this section */
149 #define	L1_S_XSCALE_TEX(x) ((x) << 12)	/* Type Extension */
150 
151 /* L1 Coarse Descriptor */
152 #define	L1_C_IMP0	0x00000004	/* implementation defined */
153 #define	L1_C_IMP1	0x00000008	/* implementation defined */
154 #define	L1_C_IMP2	0x00000010	/* implementation defined */
155 #define	L1_C_DOM(x)	((x) << 5)	/* domain */
156 #define	L1_C_DOM_MASK	L1_C_DOM(0xf)
157 #define	L1_C_ADDR_MASK	0xfffffc00	/* phys address of L2 Table */
158 
159 #define	L1_C_XSCALE_P	0x00000200	/* ECC enable for this section */
160 
161 /* L1 Fine Descriptor */
162 #define	L1_F_IMP0	0x00000004	/* implementation defined */
163 #define	L1_F_IMP1	0x00000008	/* implementation defined */
164 #define	L1_F_IMP2	0x00000010	/* implementation defined */
165 #define	L1_F_DOM(x)	((x) << 5)	/* domain */
166 #define	L1_F_DOM_MASK	L1_F_DOM(0xf)
167 #define	L1_F_ADDR_MASK	0xfffff000	/* phys address of L2 Table */
168 
169 #define	L1_F_XSCALE_P	0x00000200	/* ECC enable for this section */
170 
171 /*
172  * ARM L2 Descriptors
173  */
174 
175 #define	L2_TYPE_INV	0x00		/* Invalid (fault) */
176 #define	L2_TYPE_L	0x01		/* Large Page */
177 #define	L2_TYPE_S	0x02		/* Small Page */
178 #define	L2_TYPE_T	0x03		/* Tiny Page */
179 #define	L2_TYPE_MASK	0x03		/* mask of type bits */
180 
181 	/*
182 	 * This L2 Descriptor type is available on XScale processors
183 	 * when using a Coarse L1 Descriptor.  The Extended Small
184 	 * Descriptor has the same format as the XScale Tiny Descriptor,
185 	 * but describes a 4K page, rather than a 1K page.
186 	 */
187 #define	L2_TYPE_XSCALE_XS 0x03		/* XScale Extended Small Page */
188 
189 #define	L2_B		0x00000004	/* Bufferable page */
190 #define	L2_C		0x00000008	/* Cacheable page */
191 #define	L2_AP0(x)	((x) << 4)	/* access permissions (sp 0) */
192 #define	L2_AP1(x)	((x) << 6)	/* access permissions (sp 1) */
193 #define	L2_AP2(x)	((x) << 8)	/* access permissions (sp 2) */
194 #define	L2_AP3(x)	((x) << 10)	/* access permissions (sp 3) */
195 #define	L2_AP(x)	(L2_AP0(x) | L2_AP1(x) | L2_AP2(x) | L2_AP3(x))
196 
197 #define	L2_XSCALE_L_TEX(x) ((x) << 12)	/* Type Extension */
198 #define	L2_XSCALE_T_TEX(x) ((x) << 6)	/* Type Extension */
199 
200 /*
201  * Access Permissions for L1 and L2 Descriptors.
202  */
203 #define	AP_W		0x01		/* writable */
204 #define	AP_U		0x02		/* user */
205 
206 /*
207  * Short-hand for common AP_* constants.
208  *
209  * Note: These values assume the S (System) bit is set and
210  * the R (ROM) bit is clear in CP15 register 1.
211  */
212 #define	AP_KR		0x00		/* kernel read */
213 #define	AP_KRW		0x01		/* kernel read/write */
214 #define	AP_KRWUR	0x02		/* kernel read/write usr read */
215 #define	AP_KRWURW	0x03		/* kernel read/write usr read/write */
216 
217 /*
218  * Domain Types for the Domain Access Control Register.
219  */
220 #define	DOMAIN_FAULT	0x00		/* no access */
221 #define	DOMAIN_CLIENT	0x01		/* client */
222 #define	DOMAIN_RESERVED	0x02		/* reserved */
223 #define	DOMAIN_MANAGER	0x03		/* manager */
224 
225 /*
226  * Type Extension bits for XScale processors.
227  *
228  * Behavior of C and B when X == 0:
229  *
230  * C B  Cacheable  Bufferable  Write Policy  Line Allocate Policy
231  * 0 0      N          N            -                 -
232  * 0 1      N          Y            -                 -
233  * 1 0      Y          Y       Write-through    Read Allocate
234  * 1 1      Y          Y        Write-back      Read Allocate
235  *
236  * Behavior of C and B when X == 1:
237  * C B  Cacheable  Bufferable  Write Policy  Line Allocate Policy
238  * 0 0      -          -            -                 -           DO NOT USE
239  * 0 1      N          Y            -                 -
240  * 1 0  Mini-Data      -            -                 -
241  * 1 1      Y          Y        Write-back       R/W Allocate
242  */
243 #define	TEX_XSCALE_X	0x01		/* X modifies C and B */
244 
245 #endif /* _ARM_PTE_H_ */
246