xref: /netbsd-src/sys/arch/arm/include/arm32/pmap.h (revision 9fbd88883c38d0c0fbfcbe66d76fe6b0fab3f9de)
1 /*	$NetBSD: pmap.h,v 1.20 2002/01/19 16:55:22 chs Exp $	*/
2 
3 /*
4  * Copyright (c) 1994,1995 Mark Brinicombe.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Mark Brinicombe
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef	_ARM32_PMAP_H_
34 #define	_ARM32_PMAP_H_
35 
36 #ifdef _KERNEL
37 
38 #include <arm/cpufunc.h>
39 #include <arm/arm32/pte.h>
40 #include <uvm/uvm_object.h>
41 
42 /*
43  * a pmap describes a processes' 4GB virtual address space.  this
44  * virtual address space can be broken up into 4096 1MB regions which
45  * are described by PDEs in the PDP.  the PDEs are defined as follows:
46  *
47  * (ranges are inclusive -> exclusive, just like vm_map_entry start/end)
48  * (the following assumes that KERNBASE is 0xf0000000)
49  *
50  * PDE#s	VA range		usage
51  * 0->3835	0x0 -> 0xefc00000	user address space
52  * 3836->3839	0xefc00000->		recursive mapping of PDP (used for
53  *			0xf0000000	linear mapping of PTPs)
54  * 3840->3851	0xf0000000->		kernel text address space (constant
55  *			0xf0c00000	across all pmap's/processes)
56  * 3852->3855	0xf0c00000->		"alternate" recursive PDP mapping
57  *			0xf1000000	(for other pmaps)
58  * 3856->4095	0xf1000000->		KVM and device mappings, constant
59  *			0x00000000	across all pmaps
60  *
61  * The maths works out that to then map each 1MB block into 4k pages requires
62  * 256 entries, of 4 bytes each, totaling 1k per 1MB.  However as we use 4k
63  * pages we allocate 4 PDE's at a time, allocating the same access permissions
64  * to them all.  This means we only need 1024 entries in the page table page
65  * table, IE we use 1 4k page to linearly map all the other page tables used.
66  */
67 
68 /*
69  * Data structures used by pmap
70  */
71 
72 /*
73  * Structure that describes a Level 1 page table and the flags
74  * associated with it.
75  */
76 struct l1pt {
77 	SIMPLEQ_ENTRY(l1pt)	pt_queue;	/* Queue pointers */
78 	struct pglist		pt_plist;	/* Allocated page list */
79 	vaddr_t			pt_va;		/* Allocated virtual address */
80 	int	                pt_flags;	/* Flags */
81 };
82 #define	PTFLAG_STATIC		1		/* Statically allocated */
83 #define PTFLAG_KPT		2		/* Kernel pt's are mapped */
84 #define PTFLAG_CLEAN		4		/* L1 is clean */
85 
86 /*
87  * The pmap structure itself.
88  */
89 struct pmap {
90 	struct uvm_object	pm_obj;		/* uvm_object */
91 #define	pm_lock	pm_obj.vmobjlock
92 	pd_entry_t		*pm_pdir;	/* KVA of page directory */
93 	struct l1pt		*pm_l1pt;	/* L1 descriptor */
94 	paddr_t                 pm_pptpt;	/* PA of pt's page table */
95 	vaddr_t                 pm_vptpt;	/* VA of pt's page table */
96 	struct pmap_statistics	pm_stats;	/* pmap statistics */
97 };
98 
99 typedef struct pmap *pmap_t;
100 
101 /*
102  * for each managed physical page we maintain a list of <PMAP,VA>'s
103  * which it is mapped at.  the list is headed by a pv_head structure.
104  * there is one pv_head per managed phys page (allocated at boot time).
105  * the pv_head structure points to a list of pv_entry structures (each
106  * describes one mapping).
107  *
108  * pv_entry's are only visible within pmap.c, so only provide a placeholder
109  * here
110  */
111 
112 struct pv_entry;
113 
114 struct pv_head {
115 	struct simplelock pvh_lock;	/* locks every pv on this list */
116 	struct pv_entry *pvh_list;	/* head of list (locked by pvh_lock) */
117 };
118 
119 /*
120  * Page hooks. I'll eliminate these sometime soon :-)
121  *
122  * For speed we store the both the virtual address and the page table
123  * entry address for each page hook.
124  */
125 typedef struct {
126         vaddr_t va;
127         pt_entry_t *pte;
128 } pagehook_t;
129 
130 /*
131  * Physical / virtual address structure. In a number of places (particularly
132  * during bootstrapping) we need to keep track of the physical and virtual
133  * addresses of various pages
134  */
135 typedef struct {
136 	paddr_t pv_pa;
137 	vaddr_t pv_va;
138 } pv_addr_t;
139 
140 /*
141  * _KERNEL specific macros, functions and prototypes
142  */
143 
144 #ifdef  _KERNEL
145 
146 /*
147  * Commonly referenced structures
148  */
149 extern struct pv_entry	*pv_table;	/* Phys to virt mappings, per page. */
150 extern struct pmap	kernel_pmap_store;
151 extern int		pmap_debug_level; /* Only exists if PMAP_DEBUG */
152 
153 /*
154  * Macros that we need to export
155  */
156 #define pmap_kernel()			(&kernel_pmap_store)
157 #define	pmap_resident_count(pmap)	((pmap)->pm_stats.resident_count)
158 #define	pmap_wired_count(pmap)		((pmap)->pm_stats.wired_count)
159 
160 #define pmap_phys_address(ppn)		(arm_page_to_byte((ppn)))
161 
162 /*
163  * Functions that we need to export
164  */
165 extern vaddr_t pmap_map __P((vaddr_t, vaddr_t, vaddr_t, int));
166 extern void pmap_procwr __P((struct proc *, vaddr_t, int));
167 #define	PMAP_NEED_PROCWR
168 
169 /*
170  * Functions we use internally
171  */
172 void pmap_bootstrap __P((pd_entry_t *, pv_addr_t));
173 void pmap_debug	__P((int));
174 int pmap_handled_emulation __P((struct pmap *, vaddr_t));
175 int pmap_modified_emulation __P((struct pmap *, vaddr_t));
176 void pmap_postinit __P((void));
177 pt_entry_t *pmap_pte __P((struct pmap *, vaddr_t));
178 
179 /*
180  * Special page zero routine for use by the idle loop (no cache cleans).
181  */
182 boolean_t	pmap_pageidlezero __P((paddr_t));
183 #define PMAP_PAGEIDLEZERO(pa)	pmap_pageidlezero((pa))
184 
185 #endif	/* _KERNEL */
186 
187 /*
188  * Useful macros and constants
189  */
190 
191 /* Virtual address to page table entry */
192 #define vtopte(va) \
193 	((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE + \
194 	(arm_byte_to_page((unsigned int)(va)) << 2)))
195 
196 /* Virtual address to physical address */
197 #define vtophys(va) \
198 	((*vtopte(va) & PG_FRAME) | ((unsigned int)(va) & ~PG_FRAME))
199 
200 /* L1 and L2 page table macros */
201 #define pmap_pde(m, v) (&((m)->pm_pdir[((vaddr_t)(v) >> PDSHIFT)&4095]))
202 #define pmap_pte_pa(pte)	(*(pte) & PG_FRAME)
203 #define pmap_pde_v(pde)		(*(pde) != 0)
204 #define pmap_pde_section(pde)	((*(pde) & L1_MASK) == L1_SECTION)
205 #define pmap_pde_page(pde)	((*(pde) & L1_MASK) == L1_PAGE)
206 #define pmap_pde_fpage(pde)	((*(pde) & L1_MASK) == L1_FPAGE)
207 
208 #define pmap_pte_v(pte)		(*(pte) != 0)
209 
210 /* Size of the kernel part of the L1 page table */
211 #define KERNEL_PD_SIZE	\
212 	(PD_SIZE - (KERNEL_SPACE_START >> PDSHIFT) * sizeof(pd_entry_t))
213 
214 /*
215  * tell MI code that the cache is virtually-indexed *and* virtually-tagged.
216  */
217 
218 #define PMAP_CACHE_VIVT
219 
220 #endif /* _KERNEL */
221 
222 #endif	/* _ARM32_PMAP_H_ */
223