Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /** |
151e7659 | 2 | * Copyright (c) ???? Jochen Schäuble <psionic@psionic.de> |
2b54aaef | 3 | * Copyright (c) 2003-2004 Joern Engel <joern@wh.fh-wedel.de> |
1da177e4 LT |
4 | * |
5 | * Usage: | |
6 | * | |
7 | * one commend line parameter per device, each in the form: | |
8 | * phram=<name>,<start>,<len> | |
9 | * <name> may be up to 63 characters. | |
10 | * <start> and <len> can be octal, decimal or hexadecimal. If followed | |
11 | * by "ki", "Mi" or "Gi", the numbers will be interpreted as kilo, mega or | |
12 | * gigabytes. | |
13 | * | |
14 | * Example: | |
15 | * phram=swap,64Mi,128Mi phram=test,900Mi,1Mi | |
1da177e4 | 16 | */ |
64da392a | 17 | |
1cd844fe | 18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
64da392a | 19 | |
b85b8d92 | 20 | #include <linux/io.h> |
1da177e4 LT |
21 | #include <linux/init.h> |
22 | #include <linux/kernel.h> | |
23 | #include <linux/list.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/moduleparam.h> | |
4e57b681 | 26 | #include <linux/slab.h> |
1da177e4 LT |
27 | #include <linux/mtd/mtd.h> |
28 | ||
1da177e4 LT |
29 | struct phram_mtd_list { |
30 | struct mtd_info mtd; | |
31 | struct list_head list; | |
32 | }; | |
33 | ||
34 | static LIST_HEAD(phram_list); | |
35 | ||
1da177e4 LT |
36 | static int phram_erase(struct mtd_info *mtd, struct erase_info *instr) |
37 | { | |
38 | u_char *start = mtd->priv; | |
39 | ||
1da177e4 LT |
40 | memset(start + instr->addr, 0xff, instr->len); |
41 | ||
b2a2a84d HF |
42 | /* |
43 | * This'll catch a few races. Free the thing before returning :) | |
1da177e4 LT |
44 | * I don't feel at all ashamed. This kind of thing is possible anyway |
45 | * with flash, but unlikely. | |
46 | */ | |
1da177e4 | 47 | instr->state = MTD_ERASE_DONE; |
1da177e4 | 48 | mtd_erase_callback(instr); |
1da177e4 LT |
49 | return 0; |
50 | } | |
51 | ||
52 | static int phram_point(struct mtd_info *mtd, loff_t from, size_t len, | |
a98889f3 | 53 | size_t *retlen, void **virt, resource_size_t *phys) |
1da177e4 | 54 | { |
a98889f3 | 55 | *virt = mtd->priv + from; |
1da177e4 LT |
56 | *retlen = len; |
57 | return 0; | |
58 | } | |
59 | ||
5e4e6e3f | 60 | static int phram_unpoint(struct mtd_info *mtd, loff_t from, size_t len) |
1da177e4 | 61 | { |
5e4e6e3f | 62 | return 0; |
1da177e4 LT |
63 | } |
64 | ||
65 | static int phram_read(struct mtd_info *mtd, loff_t from, size_t len, | |
66 | size_t *retlen, u_char *buf) | |
67 | { | |
68 | u_char *start = mtd->priv; | |
69 | ||
1da177e4 | 70 | memcpy(buf, start + from, len); |
1da177e4 LT |
71 | *retlen = len; |
72 | return 0; | |
73 | } | |
74 | ||
75 | static int phram_write(struct mtd_info *mtd, loff_t to, size_t len, | |
76 | size_t *retlen, const u_char *buf) | |
77 | { | |
78 | u_char *start = mtd->priv; | |
79 | ||
1da177e4 | 80 | memcpy(start + to, buf, len); |
1da177e4 LT |
81 | *retlen = len; |
82 | return 0; | |
83 | } | |
84 | ||
1da177e4 LT |
85 | static void unregister_devices(void) |
86 | { | |
d30f11d2 | 87 | struct phram_mtd_list *this, *safe; |
1da177e4 | 88 | |
d30f11d2 | 89 | list_for_each_entry_safe(this, safe, &phram_list, list) { |
ee0e87b1 | 90 | mtd_device_unregister(&this->mtd); |
1da177e4 | 91 | iounmap(this->mtd.priv); |
f17f12ce | 92 | kfree(this->mtd.name); |
1da177e4 LT |
93 | kfree(this); |
94 | } | |
95 | } | |
96 | ||
2a46f835 | 97 | static int register_device(char *name, phys_addr_t start, size_t len) |
1da177e4 LT |
98 | { |
99 | struct phram_mtd_list *new; | |
100 | int ret = -ENOMEM; | |
101 | ||
95b93a0c | 102 | new = kzalloc(sizeof(*new), GFP_KERNEL); |
1da177e4 LT |
103 | if (!new) |
104 | goto out0; | |
105 | ||
1da177e4 LT |
106 | ret = -EIO; |
107 | new->mtd.priv = ioremap(start, len); | |
108 | if (!new->mtd.priv) { | |
64da392a | 109 | pr_err("ioremap failed\n"); |
1da177e4 LT |
110 | goto out1; |
111 | } | |
112 | ||
113 | ||
114 | new->mtd.name = name; | |
115 | new->mtd.size = len; | |
a6c591ed | 116 | new->mtd.flags = MTD_CAP_RAM; |
3c3c10bb AB |
117 | new->mtd._erase = phram_erase; |
118 | new->mtd._point = phram_point; | |
119 | new->mtd._unpoint = phram_unpoint; | |
120 | new->mtd._read = phram_read; | |
121 | new->mtd._write = phram_write; | |
1da177e4 | 122 | new->mtd.owner = THIS_MODULE; |
21c8db9e | 123 | new->mtd.type = MTD_RAM; |
663259a4 | 124 | new->mtd.erasesize = PAGE_SIZE; |
17ffc7ba | 125 | new->mtd.writesize = 1; |
1da177e4 LT |
126 | |
127 | ret = -EAGAIN; | |
ee0e87b1 | 128 | if (mtd_device_register(&new->mtd, NULL, 0)) { |
64da392a | 129 | pr_err("Failed to register new device\n"); |
1da177e4 LT |
130 | goto out2; |
131 | } | |
132 | ||
133 | list_add_tail(&new->list, &phram_list); | |
e5580fbe | 134 | return 0; |
1da177e4 LT |
135 | |
136 | out2: | |
137 | iounmap(new->mtd.priv); | |
138 | out1: | |
139 | kfree(new); | |
140 | out0: | |
141 | return ret; | |
142 | } | |
143 | ||
2a46f835 | 144 | static int parse_num64(uint64_t *num64, char *token) |
1da177e4 | 145 | { |
2a46f835 AS |
146 | size_t len; |
147 | int shift = 0; | |
148 | int ret; | |
149 | ||
150 | len = strlen(token); | |
1da177e4 | 151 | /* By dwmw2 editorial decree, "ki", "Mi" or "Gi" are to be used. */ |
2a46f835 AS |
152 | if (len > 2) { |
153 | if (token[len - 1] == 'i') { | |
154 | switch (token[len - 2]) { | |
155 | case 'G': | |
156 | shift += 10; | |
157 | case 'M': | |
158 | shift += 10; | |
159 | case 'k': | |
160 | shift += 10; | |
161 | token[len - 2] = 0; | |
162 | break; | |
163 | default: | |
164 | return -EINVAL; | |
165 | } | |
166 | } | |
1da177e4 | 167 | } |
1da177e4 | 168 | |
2a46f835 AS |
169 | ret = kstrtou64(token, 0, num64); |
170 | *num64 <<= shift; | |
1da177e4 | 171 | |
2a46f835 | 172 | return ret; |
1da177e4 LT |
173 | } |
174 | ||
175 | static int parse_name(char **pname, const char *token) | |
176 | { | |
177 | size_t len; | |
178 | char *name; | |
179 | ||
180 | len = strlen(token) + 1; | |
181 | if (len > 64) | |
182 | return -ENOSPC; | |
183 | ||
89384f64 | 184 | name = kstrdup(token, GFP_KERNEL); |
1da177e4 LT |
185 | if (!name) |
186 | return -ENOMEM; | |
187 | ||
1da177e4 LT |
188 | *pname = name; |
189 | return 0; | |
190 | } | |
191 | ||
663259a4 JE |
192 | |
193 | static inline void kill_final_newline(char *str) | |
194 | { | |
195 | char *newline = strrchr(str, '\n'); | |
c95777a4 | 196 | |
663259a4 JE |
197 | if (newline && !newline[1]) |
198 | *newline = 0; | |
199 | } | |
200 | ||
201 | ||
1da177e4 | 202 | #define parse_err(fmt, args...) do { \ |
64da392a MF |
203 | pr_err(fmt , ## args); \ |
204 | return 1; \ | |
1da177e4 LT |
205 | } while (0) |
206 | ||
6f6b9fee AS |
207 | #ifndef MODULE |
208 | static int phram_init_called; | |
b2a2a84d HF |
209 | /* |
210 | * This shall contain the module parameter if any. It is of the form: | |
211 | * - phram=<device>,<address>,<size> for module case | |
212 | * - phram.phram=<device>,<address>,<size> for built-in case | |
2a46f835 | 213 | * We leave 64 bytes for the device name, 20 for the address and 20 for the |
b2a2a84d HF |
214 | * size. |
215 | * Example: phram.phram=rootfs,0xa0000000,512Mi | |
216 | */ | |
6f6b9fee AS |
217 | static char phram_paramline[64 + 20 + 20]; |
218 | #endif | |
b2a2a84d | 219 | |
6f6b9fee | 220 | static int phram_setup(const char *val) |
1da177e4 | 221 | { |
2a46f835 | 222 | char buf[64 + 20 + 20], *str = buf; |
1da177e4 LT |
223 | char *token[3]; |
224 | char *name; | |
2a46f835 AS |
225 | uint64_t start; |
226 | uint64_t len; | |
1da177e4 LT |
227 | int i, ret; |
228 | ||
229 | if (strnlen(val, sizeof(buf)) >= sizeof(buf)) | |
230 | parse_err("parameter too long\n"); | |
231 | ||
232 | strcpy(str, val); | |
663259a4 | 233 | kill_final_newline(str); |
1da177e4 | 234 | |
c95777a4 | 235 | for (i = 0; i < 3; i++) |
1da177e4 LT |
236 | token[i] = strsep(&str, ","); |
237 | ||
238 | if (str) | |
239 | parse_err("too many arguments\n"); | |
240 | ||
241 | if (!token[2]) | |
242 | parse_err("not enough arguments\n"); | |
243 | ||
244 | ret = parse_name(&name, token[0]); | |
1da177e4 | 245 | if (ret) |
64da392a | 246 | return ret; |
1da177e4 | 247 | |
2a46f835 | 248 | ret = parse_num64(&start, token[1]); |
4f678a58 JJ |
249 | if (ret) { |
250 | kfree(name); | |
1da177e4 | 251 | parse_err("illegal start address\n"); |
4f678a58 | 252 | } |
1da177e4 | 253 | |
2a46f835 | 254 | ret = parse_num64(&len, token[2]); |
4f678a58 JJ |
255 | if (ret) { |
256 | kfree(name); | |
1da177e4 | 257 | parse_err("illegal device length\n"); |
4f678a58 | 258 | } |
1da177e4 | 259 | |
64da392a MF |
260 | ret = register_device(name, start, len); |
261 | if (!ret) | |
2a46f835 | 262 | pr_info("%s device: %#llx at %#llx\n", name, len, start); |
f17f12ce MK |
263 | else |
264 | kfree(name); | |
1da177e4 | 265 | |
64da392a | 266 | return ret; |
1da177e4 LT |
267 | } |
268 | ||
6f6b9fee | 269 | static int phram_param_call(const char *val, struct kernel_param *kp) |
b2a2a84d | 270 | { |
6f6b9fee AS |
271 | #ifdef MODULE |
272 | return phram_setup(val); | |
273 | #else | |
b2a2a84d | 274 | /* |
6f6b9fee AS |
275 | * If more parameters are later passed in via |
276 | * /sys/module/phram/parameters/phram | |
277 | * and init_phram() has already been called, | |
278 | * we can parse the argument now. | |
b2a2a84d | 279 | */ |
6f6b9fee AS |
280 | |
281 | if (phram_init_called) | |
282 | return phram_setup(val); | |
283 | ||
284 | /* | |
285 | * During early boot stage, we only save the parameters | |
286 | * here. We must parse them later: if the param passed | |
287 | * from kernel boot command line, phram_param_call() is | |
288 | * called so early that it is not possible to resolve | |
289 | * the device (even kmalloc() fails). Defer that work to | |
290 | * phram_setup(). | |
291 | */ | |
292 | ||
b2a2a84d HF |
293 | if (strlen(val) >= sizeof(phram_paramline)) |
294 | return -ENOSPC; | |
295 | strcpy(phram_paramline, val); | |
296 | ||
297 | return 0; | |
6f6b9fee | 298 | #endif |
b2a2a84d HF |
299 | } |
300 | ||
301 | module_param_call(phram, phram_param_call, NULL, NULL, 000); | |
f72561cf | 302 | MODULE_PARM_DESC(phram, "Memory region to map. \"phram=<name>,<start>,<length>\""); |
1da177e4 LT |
303 | |
304 | ||
305 | static int __init init_phram(void) | |
306 | { | |
6f6b9fee AS |
307 | int ret = 0; |
308 | ||
309 | #ifndef MODULE | |
b2a2a84d | 310 | if (phram_paramline[0]) |
6f6b9fee AS |
311 | ret = phram_setup(phram_paramline); |
312 | phram_init_called = 1; | |
313 | #endif | |
b2a2a84d | 314 | |
6f6b9fee | 315 | return ret; |
1da177e4 LT |
316 | } |
317 | ||
318 | static void __exit cleanup_phram(void) | |
319 | { | |
320 | unregister_devices(); | |
321 | } | |
322 | ||
323 | module_init(init_phram); | |
324 | module_exit(cleanup_phram); | |
325 | ||
326 | MODULE_LICENSE("GPL"); | |
2b54aaef | 327 | MODULE_AUTHOR("Joern Engel <joern@wh.fh-wedel.de>"); |
1da177e4 | 328 | MODULE_DESCRIPTION("MTD driver for physical RAM"); |