xref: /netbsd-src/sys/arch/sun3/sun3x/pmap_pvt.h (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: pmap_pvt.h,v 1.6 1997/07/02 03:23:58 jeremy Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jeremy Cooper.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #ifndef _SUN3X_PMAPPVT_H
40 #define _SUN3X_PMAPPVT_H
41 
42 /*************************** TMGR STRUCTURES ***************************
43  * The sun3x 'tmgr' structures contain MMU tables and additional       *
44  * information about their current usage and availability.             *
45  ***********************************************************************/
46 typedef struct a_tmgr_struct a_tmgr_t;
47 typedef struct b_tmgr_struct b_tmgr_t;
48 typedef struct c_tmgr_struct c_tmgr_t;
49 
50 /* A level A table manager contains a pointer to an MMU table of long
51  * format table descriptors (an 'A' table), a pointer to the pmap
52  * currently using the table, and the number of wired and active entries
53  * it contains.
54  */
55 struct a_tmgr_struct {
56 	pmap_t		at_parent; /* pmap currently using this table    */
57 	mmu_long_dte_t	*at_dtbl;  /* the MMU table being managed        */
58 	u_char          at_wcnt;   /* no. of wired entries in this table */
59 	u_char          at_ecnt;   /* no. of valid entries in this table */
60     	TAILQ_ENTRY(a_tmgr_struct) at_link;  /* list linker              */
61 };
62 
63 /* A level B table manager contains a pointer to an MMU table of
64  * short format table descriptors (a 'B' table), a pointer to the level
65  * A table manager currently using it, the index of this B table
66  * within that parent A table, and the number of wired and active entries
67  * it currently contains.
68  */
69 struct b_tmgr_struct {
70 	a_tmgr_t	*bt_parent; /* Parent 'A' table manager         */
71 	mmu_short_dte_t *bt_dtbl;   /* the MMU table being managed      */
72 	u_char		bt_pidx;    /* this table's index in the parent */
73 	u_char		bt_wcnt;    /* no. of wired entries in table    */
74 	u_char		bt_ecnt;    /* no. of valid entries in table    */
75     	TAILQ_ENTRY(b_tmgr_struct) bt_link; /* list linker              */
76 };
77 
78 /* A level 'C' table manager consists of pointer to an MMU table of short
79  * format page descriptors (a 'C' table), a pointer to the level B table
80  * manager currently using it, and the number of wired and active pages
81  * it currently contains.
82  *
83  * Additionally, the table manager contains a pointer to the pmap
84  * that is currently using it and the starting virtual address of the
85  * range that the MMU table manages.  These two items can be obtained
86  * through the traversal of other table manager structures, but having
87  * them close at hand helps speed up operations in the PV system.
88  */
89 struct c_tmgr_struct {
90 	b_tmgr_t	*ct_parent; /* Parent 'B' table manager         */
91 	mmu_short_pte_t	*ct_dtbl;   /* the MMU table being managed      */
92 	u_char		ct_pidx;    /* this table's index in the parent */
93 	u_char		ct_wcnt;    /* no. of wired entries in table    */
94 	u_char		ct_ecnt;    /* no. of valid entries in table    */
95 	TAILQ_ENTRY(c_tmgr_struct) ct_link; /* list linker              */
96 #define	MMU_SHORT_PTE_WIRED	MMU_SHORT_PTE_UN1
97 #define MMU_PTE_WIRED		((*pte)->attr.raw & MMU_SHORT_PTE_WIRED)
98 	pmap_t		ct_pmap;    /* pmap currently using this table  */
99 	vm_offset_t	ct_va;      /* starting va that this table maps */
100 };
101 
102 /* The Mach VM code requires that the pmap module be able to apply
103  * several different operations on all page descriptors that map to a
104  * given physical address.  A few of these are:
105  *  + invalidate all mappings to a page.
106  *  + change the type of protection on all mappings to a page.
107  *  + determine if a physical page has been written to
108  *  + determine if a physical page has been accessed (read from)
109  *  + clear such information
110  * The collection of structures and tables which we used to make this
111  * possible is known as the 'Physical to Virtual' or 'PV' system.
112  *
113  * Every physical page of memory managed by the virtual memory system
114  * will have a structure which describes whether or not it has been
115  * modified or referenced, and contains a list of page descriptors that
116  * are currently mapped to it (if any).  This array of structures is
117  * known as the 'PV' list.
118  *
119  ** Old PV Element structure
120  * To keep a list of page descriptors currently using the page, another
121  * structure had to be invented.  Its sole purpose is to be a link in
122  * a chain of such structures.  No other information is contained within
123  * the structure however!  The other piece of information it holds is
124  * hidden within its address.  By maintaining a one-to-one correspondence
125  * of page descriptors in the system and such structures, this address can
126  * readily be translated into its associated page descriptor by using a
127  * simple macro.  This bizzare structure is simply known as a 'PV
128  * Element', or 'pve' for short.
129  *
130  ** New PV Element structure
131  * To keep a list of page descriptors currently using the page, another
132  * structure had to be invented.  Its sole purpose is to indicate the index
133  * of the next PTE currently referencing the page.  By maintaining a one-to-
134  * one correspondence of page descriptors in the system and such structures,
135  * this same index is also the index of the next PV element, which describes
136  * the index of yet another page mapped to the same address and so on.  The
137  * special index 'PVE_EOL' is used to represent the end of the list.
138  */
139 struct pv_struct {
140 	u_short	pv_idx;		/* Index of PTE using this page */
141 	u_short	pv_flags;	/* Physical page status flags */
142 #define PV_FLAGS_USED	MMU_SHORT_PTE_USED
143 #define PV_FLAGS_MDFY	MMU_SHORT_PTE_M
144 };
145 typedef struct pv_struct pv_t;
146 
147 struct pv_elem_struct {
148 	u_short	pve_next;
149 #define	PVE_EOL	0xffff		/* End-of-list marker */
150 };
151 typedef struct pv_elem_struct pv_elem_t;
152 
153 /* Physical memory on the 3/80 is not contiguous.  The ROM Monitor
154  * provides us with a linked list of memory segments describing each
155  * segment with its base address and its size.
156  */
157 struct pmap_physmem_struct {
158 	vm_offset_t	pmem_start;  /* Starting physical address      */
159 	vm_offset_t	pmem_end;    /* First byte outside of range    */
160 	int             pmem_pvbase; /* Offset within the pv list      */
161 	struct pmap_physmem_struct *pmem_next; /* Next block of memory */
162 };
163 
164 /* Internal function definitions. */
165 a_tmgr_t *get_a_table __P((void));
166 b_tmgr_t *get_b_table __P((void));
167 c_tmgr_t *get_c_table __P((void));
168 int    free_a_table __P((a_tmgr_t *, boolean_t));
169 int    free_b_table __P((b_tmgr_t *, boolean_t));
170 int    free_c_table __P((c_tmgr_t *, boolean_t));
171 void   pmap_bootstrap_aalign __P((int));
172 void   pmap_alloc_usermmu __P((void));
173 void   pmap_alloc_usertmgr __P((void));
174 void   pmap_alloc_pv __P((void));
175 void   pmap_init_a_tables __P((void));
176 void   pmap_init_b_tables __P((void));
177 void   pmap_init_c_tables __P((void));
178 void   pmap_init_pv __P((void));
179 void   pmap_clear_pv __P((vm_offset_t, int));
180 boolean_t pmap_remove_a __P((a_tmgr_t *, vm_offset_t, vm_offset_t));
181 boolean_t pmap_remove_b __P((b_tmgr_t *, vm_offset_t, vm_offset_t));
182 boolean_t pmap_remove_c __P((c_tmgr_t *, vm_offset_t, vm_offset_t));
183 void   pmap_remove_pte __P((mmu_short_pte_t *));
184 void   pmap_enter_kernel __P((vm_offset_t, vm_offset_t, vm_prot_t));
185 void   pmap_remove_kernel __P((vm_offset_t, vm_offset_t));
186 void   pmap_protect_kernel __P((vm_offset_t, vm_offset_t, vm_prot_t));
187 vm_offset_t pmap_extract_kernel __P((vm_offset_t));
188 vm_offset_t pmap_get_pteinfo __P((u_int, pmap_t *, c_tmgr_t **));
189 void   pmap_pinit __P((pmap_t));
190 int    pmap_dereference __P((pmap_t));
191 boolean_t is_managed __P((vm_offset_t));
192 boolean_t pmap_stroll __P((pmap_t, vm_offset_t, a_tmgr_t **, b_tmgr_t **,\
193 	c_tmgr_t **, mmu_short_pte_t **, int *, int *, int *));
194 void  pmap_bootstrap_copyprom __P((void));
195 void  pmap_takeover_mmu __P((void));
196 void  pmap_bootstrap_setprom __P((void));
197 
198 /* Debugging function definitions */
199 void  pv_list __P((vm_offset_t, int));
200 
201 /* These are defined in pmap.c */
202 extern struct pmap_physmem_struct avail_mem[];
203 
204 #endif /* _SUN3X_MYPMAP_H */
205