1 /* $NetBSD: pmap_devmap.c,v 1.2 2023/04/27 06:23:31 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2022 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Nick Hudson
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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: pmap_devmap.c,v 1.2 2023/04/27 06:23:31 skrll Exp $");
34
35
36 #include <sys/param.h>
37 #include <sys/types.h>
38
39 #include <uvm/uvm.h>
40 #include <uvm/uvm_extern.h>
41 #include <uvm/pmap/pmap_devmap.h>
42
43
44 static const struct pmap_devmap *pd_table;
45 static vaddr_t pd_root;
46
47 bool pmap_devmap_bootstrap_done = false;
48
49 bool
pmap_devmap_bootstrapped_p(void)50 pmap_devmap_bootstrapped_p(void)
51 {
52 return pmap_devmap_bootstrap_done;
53 }
54
55
56 vaddr_t
pmap_devmap_root(void)57 pmap_devmap_root(void)
58 {
59 return pd_root;
60 }
61
62 /*
63 * Register the devmap table. This is provided in case early console
64 * initialization needs to register mappings created by bootstrap code
65 * before pmap_devmap_bootstrap() is called.
66 */
67 void
pmap_devmap_register(const struct pmap_devmap * table)68 pmap_devmap_register(const struct pmap_devmap *table)
69 {
70
71 pd_table = table;
72 }
73
74 /*
75 * Map all of the static regions in the devmap table, and remember
76 * the devmap table so other parts of the kernel can look up entries
77 * later.
78 */
79 void
pmap_devmap_bootstrap(vaddr_t root,const struct pmap_devmap * table)80 pmap_devmap_bootstrap(vaddr_t root, const struct pmap_devmap *table)
81 {
82 UVMHIST_FUNC(__func__);
83 UVMHIST_CALLARGS(maphist, "(root=%#jx, table=%p)", root,
84 (uintptr_t)table, 0, 0);
85
86 bool done = false;
87
88 pd_root = root;
89 pd_table = table;
90
91 for (size_t i = 0; table[i].pd_size != 0; i++) {
92 const struct pmap_devmap * const pdp = &table[i];
93 const vaddr_t vmax = __type_max_u(vaddr_t);
94 const paddr_t pmax = __type_max_u(paddr_t);
95
96 KASSERT(pdp->pd_size != 0);
97 KASSERTMSG(vmax - pdp->pd_va >= pdp->pd_size - 1,
98 "va %" PRIxVADDR " sz %" PRIxPSIZE, pdp->pd_va,
99 pdp->pd_size);
100 KASSERTMSG(pmax - pdp->pd_pa >= pdp->pd_size - 1,
101 "pa %" PRIxPADDR " sz %" PRIxPSIZE, pdp->pd_pa,
102 pdp->pd_size);
103 UVMHIST_LOG(maphist,
104 "pa %#jx -> %#jx @ va %#jx -> %#jx",
105 pdp->pd_pa, pdp->pd_pa + pdp->pd_size - 1,
106 pdp->pd_va, pdp->pd_va + pdp->pd_size - 1);
107
108 pmap_kenter_range(pdp->pd_va, pdp->pd_pa, pdp->pd_size,
109 pdp->pd_prot, pdp->pd_flags);
110 done = true;
111 }
112 if (done)
113 pmap_devmap_bootstrap_done = true;
114 }
115
116 /*
117 * Find the table entry that fully covers the physical address
118 * range [pa, pa + size)
119 */
120 const struct pmap_devmap *
pmap_devmap_find_pa(paddr_t pa,psize_t size)121 pmap_devmap_find_pa(paddr_t pa, psize_t size)
122 {
123 if (pd_table == NULL)
124 return NULL;
125
126 for (size_t i = 0; pd_table[i].pd_size != 0; i++) {
127 const paddr_t pd_pa = pd_table[i].pd_pa;
128 const psize_t pd_sz = pd_table[i].pd_size;
129
130 if (pa < pd_pa)
131 continue;
132
133 const psize_t pdiff = pa - pd_pa;
134
135 if (pd_sz < pdiff)
136 continue;
137
138 if (pd_sz - pdiff >= size)
139 return &pd_table[i];
140 }
141
142 return NULL;
143 }
144
145 /*
146 * Find the table entry that fully covers the virtual address
147 * range [va, va + size)
148 */
149 const struct pmap_devmap *
pmap_devmap_find_va(vaddr_t va,vsize_t size)150 pmap_devmap_find_va(vaddr_t va, vsize_t size)
151 {
152 if (pd_table == NULL)
153 return NULL;
154
155 for (size_t i = 0; pd_table[i].pd_size != 0; i++) {
156 const vaddr_t pd_va = pd_table[i].pd_va;
157 const vsize_t pd_sz = pd_table[i].pd_size;
158
159 if (va < pd_va)
160 continue;
161
162 const vsize_t vdiff = va - pd_va;
163
164 if (pd_sz < vdiff)
165 continue;
166
167 if (pd_sz - vdiff >= size)
168 return &pd_table[i];
169
170 }
171
172 return NULL;
173 }
174