1 /* $NetBSD: flash_mtdparts.c,v 1.3 2021/08/07 16:19:10 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: flash_mtdparts.c,v 1.3 2021/08/07 16:19:10 thorpej Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/systm.h>
36 #include <sys/kmem.h>
37
38 #include <dev/flash/flash.h>
39
40 extern int flash_print(void *, const char *);
41
42 static void
flash_attach_partition(struct flash_interface * flash_if,device_t parent,struct flash_partition * part)43 flash_attach_partition(struct flash_interface *flash_if, device_t parent,
44 struct flash_partition *part)
45 {
46 struct flash_attach_args faa;
47
48 faa.flash_if = flash_if;
49 faa.partinfo = *part;
50
51 config_found(parent, &faa, flash_print,
52 CFARGS(.iattr = "flashbus"));
53 }
54
55 static flash_size_t
flash_parse_size(char * partdef,char ** ep)56 flash_parse_size(char *partdef, char **ep)
57 {
58 flash_size_t size;
59
60 /* Parse the size parameter */
61 size = strtoul(partdef, ep, 10);
62 if (partdef == *ep)
63 return 0;
64
65 switch (**ep) {
66 case 'G':
67 case 'g':
68 size <<= 10;
69 /* FALLTHROUGH */
70 case 'M':
71 case 'm':
72 size <<= 10;
73 /* FALLTHROUGH */
74 case 'K':
75 case 'k':
76 size <<= 10;
77 (*ep)++;
78 break;
79 }
80
81 return size;
82 }
83
84 static int
flash_parse_partdef(flash_size_t flash_size,char * partdef,flash_off_t * offset,struct flash_partition * ppart)85 flash_parse_partdef(flash_size_t flash_size, char *partdef, flash_off_t *offset,
86 struct flash_partition *ppart)
87 {
88 struct flash_partition part;
89
90 /* Get the partition size */
91 if (*partdef == '-') {
92 /* Use the remaining space */
93 part.part_size = 0;
94 partdef++;
95 } else {
96 part.part_size = flash_parse_size(partdef, &partdef);
97 if (part.part_size == 0)
98 return EINVAL;
99 }
100
101 if (*partdef == '@') {
102 /* Explicit offset */
103 partdef++;
104 part.part_offset = flash_parse_size(partdef, &partdef);
105 } else {
106 /* Offset is the end of the previous partition */
107 part.part_offset = *offset;
108 }
109
110 /* Calculate partition size for "all remaining space" parts */
111 if (part.part_size == 0)
112 part.part_size = flash_size - part.part_offset;
113
114 if (*partdef == '(') {
115 /* Partition name */
116 partdef++;
117 part.part_name = partdef;
118 partdef = strchr(partdef, ')');
119 if (partdef == NULL)
120 return EINVAL;
121 *partdef = '\0';
122 partdef++;
123 }
124
125 part.part_flags = 0;
126 if (strncmp(partdef, "ro", 2) == 0) {
127 part.part_flags |= FLASH_PART_READONLY;
128 partdef += 2;
129 }
130
131 *ppart = part;
132
133 *offset = part.part_offset + part.part_size;
134
135 return 0;
136 }
137
138 static void
flash_parse_mtddef(struct flash_interface * flash_if,device_t parent,flash_size_t flash_size,char * mtddef)139 flash_parse_mtddef(struct flash_interface *flash_if, device_t parent,
140 flash_size_t flash_size, char *mtddef)
141 {
142 struct flash_partition part;
143 char *partdef = mtddef, *nextdef;
144 flash_off_t offset = 0;
145 int error;
146
147 while (partdef && offset < flash_size) {
148 /* Find the end */
149 nextdef = strchr(partdef, ',');
150 if (nextdef == NULL)
151 nextdef = strchr(partdef, ' ');
152 if (nextdef)
153 *nextdef++ = '\0';
154
155 error = flash_parse_partdef(flash_size, partdef, &offset,
156 &part);
157 if (error) {
158 aprint_error_dev(parent, "bad partition def '%s'\n",
159 partdef);
160 return;
161 }
162
163 flash_attach_partition(flash_if, parent, &part);
164
165 partdef = nextdef;
166 }
167 }
168
169 /*
170 * Attach partitions to a given parent device node that match the supplied
171 * device id. The cmdline follows the following format:
172 *
173 * mtdparts=<mtddef>[;<mtddef]
174 * <mtddef> := <mtd-id>:<partdef>[,<partdef>]
175 * <partdef> := <size>[@offset][<name>][ro]
176 * <mtd-id> := unique id used in mapping driver/device (number of flash bank)
177 * <size> := memsize OR "-" to denote all remaining space
178 * <name> := '(' NAME ')'
179 */
180 void
flash_attach_mtdparts(struct flash_interface * flash_if,device_t parent,flash_size_t flash_size,const char * mtd_id,const char * cmdline)181 flash_attach_mtdparts(struct flash_interface *flash_if, device_t parent,
182 flash_size_t flash_size, const char *mtd_id, const char *cmdline)
183 {
184 char *mtddef;
185 size_t mtddeflen;
186
187 /* Find the definition for our mtd id */
188 const char *s = strstr(cmdline, mtd_id);
189 if (s == NULL || s[strlen(mtd_id)] != ':')
190 return;
191
192 mtddef = kmem_strdupsize(s + strlen(mtd_id) + 1, &mtddeflen, KM_SLEEP);
193
194 flash_parse_mtddef(flash_if, parent, flash_size, mtddef);
195
196 kmem_free(mtddef, mtddeflen);
197 }
198