tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * $Id: redboot.c,v 1.21 2006/03/30 18:34:37 bjd Exp $
3 *
4 * Parse RedBoot-style Flash Image System (FIS) tables and
5 * produce a Linux partition array to match.
6 */
7
8#include <linux/kernel.h>
9#include <linux/slab.h>
10#include <linux/init.h>
11#include <linux/vmalloc.h>
12
13#include <linux/mtd/mtd.h>
14#include <linux/mtd/partitions.h>
15
16struct fis_image_desc {
17 unsigned char name[16]; // Null terminated name
18 uint32_t flash_base; // Address within FLASH of image
19 uint32_t mem_base; // Address in memory where it executes
20 uint32_t size; // Length of image
21 uint32_t entry_point; // Execution entry point
22 uint32_t data_length; // Length of actual data
23 unsigned char _pad[256-(16+7*sizeof(uint32_t))];
24 uint32_t desc_cksum; // Checksum over image descriptor
25 uint32_t file_cksum; // Checksum over image data
26};
27
28struct fis_list {
29 struct fis_image_desc *img;
30 struct fis_list *next;
31};
32
33static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;
34module_param(directory, int, 0);
35
36static inline int redboot_checksum(struct fis_image_desc *img)
37{
38 /* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
39 return 1;
40}
41
42static int parse_redboot_partitions(struct mtd_info *master,
43 struct mtd_partition **pparts,
44 unsigned long fis_origin)
45{
46 int nrparts = 0;
47 struct fis_image_desc *buf;
48 struct mtd_partition *parts;
49 struct fis_list *fl = NULL, *tmp_fl;
50 int ret, i;
51 size_t retlen;
52 char *names;
53 char *nullname;
54 int namelen = 0;
55 int nulllen = 0;
56 int numslots;
57 unsigned long offset;
58#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
59 static char nullstring[] = "unallocated";
60#endif
61
62 buf = vmalloc(master->erasesize);
63
64 if (!buf)
65 return -ENOMEM;
66
67 if ( directory < 0 )
68 offset = master->size + directory*master->erasesize;
69 else
70 offset = directory*master->erasesize;
71
72 printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",
73 master->name, offset);
74
75 ret = master->read(master, offset,
76 master->erasesize, &retlen, (void *)buf);
77
78 if (ret)
79 goto out;
80
81 if (retlen != master->erasesize) {
82 ret = -EIO;
83 goto out;
84 }
85
86 numslots = (master->erasesize / sizeof(struct fis_image_desc));
87 for (i = 0; i < numslots; i++) {
88 if (!memcmp(buf[i].name, "FIS directory", 14)) {
89 /* This is apparently the FIS directory entry for the
90 * FIS directory itself. The FIS directory size is
91 * one erase block; if the buf[i].size field is
92 * swab32(erasesize) then we know we are looking at
93 * a byte swapped FIS directory - swap all the entries!
94 * (NOTE: this is 'size' not 'data_length'; size is
95 * the full size of the entry.)
96 */
97 if (swab32(buf[i].size) == master->erasesize) {
98 int j;
99 for (j = 0; j < numslots && buf[j].name[0] != 0xff; ++j) {
100 /* The unsigned long fields were written with the
101 * wrong byte sex, name and pad have no byte sex.
102 */
103 swab32s(&buf[j].flash_base);
104 swab32s(&buf[j].mem_base);
105 swab32s(&buf[j].size);
106 swab32s(&buf[j].entry_point);
107 swab32s(&buf[j].data_length);
108 swab32s(&buf[j].desc_cksum);
109 swab32s(&buf[j].file_cksum);
110 }
111 }
112 break;
113 }
114 }
115 if (i == numslots) {
116 /* Didn't find it */
117 printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
118 master->name);
119 ret = 0;
120 goto out;
121 }
122
123 for (i = 0; i < numslots; i++) {
124 struct fis_list *new_fl, **prev;
125
126 if (buf[i].name[0] == 0xff)
127 continue;
128 if (!redboot_checksum(&buf[i]))
129 break;
130
131 new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
132 namelen += strlen(buf[i].name)+1;
133 if (!new_fl) {
134 ret = -ENOMEM;
135 goto out;
136 }
137 new_fl->img = &buf[i];
138 if (fis_origin) {
139 buf[i].flash_base -= fis_origin;
140 } else {
141 buf[i].flash_base &= master->size-1;
142 }
143
144 /* I'm sure the JFFS2 code has done me permanent damage.
145 * I now think the following is _normal_
146 */
147 prev = &fl;
148 while(*prev && (*prev)->img->flash_base < new_fl->img->flash_base)
149 prev = &(*prev)->next;
150 new_fl->next = *prev;
151 *prev = new_fl;
152
153 nrparts++;
154 }
155#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
156 if (fl->img->flash_base) {
157 nrparts++;
158 nulllen = sizeof(nullstring);
159 }
160
161 for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
162 if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize <= tmp_fl->next->img->flash_base) {
163 nrparts++;
164 nulllen = sizeof(nullstring);
165 }
166 }
167#endif
168 parts = kmalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL);
169
170 if (!parts) {
171 ret = -ENOMEM;
172 goto out;
173 }
174
175 memset(parts, 0, sizeof(*parts)*nrparts + nulllen + namelen);
176
177 nullname = (char *)&parts[nrparts];
178#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
179 if (nulllen > 0) {
180 strcpy(nullname, nullstring);
181 }
182#endif
183 names = nullname + nulllen;
184
185 i=0;
186
187#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
188 if (fl->img->flash_base) {
189 parts[0].name = nullname;
190 parts[0].size = fl->img->flash_base;
191 parts[0].offset = 0;
192 i++;
193 }
194#endif
195 for ( ; i<nrparts; i++) {
196 parts[i].size = fl->img->size;
197 parts[i].offset = fl->img->flash_base;
198 parts[i].name = names;
199
200 strcpy(names, fl->img->name);
201#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY
202 if (!memcmp(names, "RedBoot", 8) ||
203 !memcmp(names, "RedBoot config", 15) ||
204 !memcmp(names, "FIS directory", 14)) {
205 parts[i].mask_flags = MTD_WRITEABLE;
206 }
207#endif
208 names += strlen(names)+1;
209
210#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
211 if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize <= fl->next->img->flash_base) {
212 i++;
213 parts[i].offset = parts[i-1].size + parts[i-1].offset;
214 parts[i].size = fl->next->img->flash_base - parts[i].offset;
215 parts[i].name = nullname;
216 }
217#endif
218 tmp_fl = fl;
219 fl = fl->next;
220 kfree(tmp_fl);
221 }
222 ret = nrparts;
223 *pparts = parts;
224 out:
225 while (fl) {
226 struct fis_list *old = fl;
227 fl = fl->next;
228 kfree(old);
229 }
230 vfree(buf);
231 return ret;
232}
233
234static struct mtd_part_parser redboot_parser = {
235 .owner = THIS_MODULE,
236 .parse_fn = parse_redboot_partitions,
237 .name = "RedBoot",
238};
239
240static int __init redboot_parser_init(void)
241{
242 return register_mtd_parser(&redboot_parser);
243}
244
245static void __exit redboot_parser_exit(void)
246{
247 deregister_mtd_parser(&redboot_parser);
248}
249
250module_init(redboot_parser_init);
251module_exit(redboot_parser_exit);
252
253MODULE_LICENSE("GPL");
254MODULE_AUTHOR("Red Hat, Inc. - David Woodhouse <dwmw2@cambridge.redhat.com>");
255MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");