Commit | Line | Data |
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09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 | 2 | /** |
151e7659 | 3 | * Copyright (c) ???? Jochen Schäuble <psionic@psionic.de> |
2b54aaef | 4 | * Copyright (c) 2003-2004 Joern Engel <joern@wh.fh-wedel.de> |
1da177e4 LT |
5 | * |
6 | * Usage: | |
7 | * | |
8 | * one commend line parameter per device, each in the form: | |
9 | * phram=<name>,<start>,<len> | |
10 | * <name> may be up to 63 characters. | |
11 | * <start> and <len> can be octal, decimal or hexadecimal. If followed | |
12 | * by "ki", "Mi" or "Gi", the numbers will be interpreted as kilo, mega or | |
13 | * gigabytes. | |
14 | * | |
15 | * Example: | |
16 | * phram=swap,64Mi,128Mi phram=test,900Mi,1Mi | |
1da177e4 | 17 | */ |
64da392a | 18 | |
1cd844fe | 19 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
64da392a | 20 | |
b85b8d92 | 21 | #include <linux/io.h> |
1da177e4 LT |
22 | #include <linux/init.h> |
23 | #include <linux/kernel.h> | |
24 | #include <linux/list.h> | |
25 | #include <linux/module.h> | |
26 | #include <linux/moduleparam.h> | |
4e57b681 | 27 | #include <linux/slab.h> |
1da177e4 LT |
28 | #include <linux/mtd/mtd.h> |
29 | ||
1da177e4 LT |
30 | struct phram_mtd_list { |
31 | struct mtd_info mtd; | |
32 | struct list_head list; | |
33 | }; | |
34 | ||
35 | static LIST_HEAD(phram_list); | |
36 | ||
1da177e4 LT |
37 | static int phram_erase(struct mtd_info *mtd, struct erase_info *instr) |
38 | { | |
39 | u_char *start = mtd->priv; | |
40 | ||
1da177e4 LT |
41 | memset(start + instr->addr, 0xff, instr->len); |
42 | ||
1da177e4 LT |
43 | return 0; |
44 | } | |
45 | ||
46 | static int phram_point(struct mtd_info *mtd, loff_t from, size_t len, | |
a98889f3 | 47 | size_t *retlen, void **virt, resource_size_t *phys) |
1da177e4 | 48 | { |
a98889f3 | 49 | *virt = mtd->priv + from; |
1da177e4 LT |
50 | *retlen = len; |
51 | return 0; | |
52 | } | |
53 | ||
5e4e6e3f | 54 | static int phram_unpoint(struct mtd_info *mtd, loff_t from, size_t len) |
1da177e4 | 55 | { |
5e4e6e3f | 56 | return 0; |
1da177e4 LT |
57 | } |
58 | ||
59 | static int phram_read(struct mtd_info *mtd, loff_t from, size_t len, | |
60 | size_t *retlen, u_char *buf) | |
61 | { | |
62 | u_char *start = mtd->priv; | |
63 | ||
1da177e4 | 64 | memcpy(buf, start + from, len); |
1da177e4 LT |
65 | *retlen = len; |
66 | return 0; | |
67 | } | |
68 | ||
69 | static int phram_write(struct mtd_info *mtd, loff_t to, size_t len, | |
70 | size_t *retlen, const u_char *buf) | |
71 | { | |
72 | u_char *start = mtd->priv; | |
73 | ||
1da177e4 | 74 | memcpy(start + to, buf, len); |
1da177e4 LT |
75 | *retlen = len; |
76 | return 0; | |
77 | } | |
78 | ||
1da177e4 LT |
79 | static void unregister_devices(void) |
80 | { | |
d30f11d2 | 81 | struct phram_mtd_list *this, *safe; |
1da177e4 | 82 | |
d30f11d2 | 83 | list_for_each_entry_safe(this, safe, &phram_list, list) { |
ee0e87b1 | 84 | mtd_device_unregister(&this->mtd); |
1da177e4 | 85 | iounmap(this->mtd.priv); |
f17f12ce | 86 | kfree(this->mtd.name); |
1da177e4 LT |
87 | kfree(this); |
88 | } | |
89 | } | |
90 | ||
2a46f835 | 91 | static int register_device(char *name, phys_addr_t start, size_t len) |
1da177e4 LT |
92 | { |
93 | struct phram_mtd_list *new; | |
94 | int ret = -ENOMEM; | |
95 | ||
95b93a0c | 96 | new = kzalloc(sizeof(*new), GFP_KERNEL); |
1da177e4 LT |
97 | if (!new) |
98 | goto out0; | |
99 | ||
1da177e4 LT |
100 | ret = -EIO; |
101 | new->mtd.priv = ioremap(start, len); | |
102 | if (!new->mtd.priv) { | |
64da392a | 103 | pr_err("ioremap failed\n"); |
1da177e4 LT |
104 | goto out1; |
105 | } | |
106 | ||
107 | ||
108 | new->mtd.name = name; | |
109 | new->mtd.size = len; | |
a6c591ed | 110 | new->mtd.flags = MTD_CAP_RAM; |
3c3c10bb AB |
111 | new->mtd._erase = phram_erase; |
112 | new->mtd._point = phram_point; | |
113 | new->mtd._unpoint = phram_unpoint; | |
114 | new->mtd._read = phram_read; | |
115 | new->mtd._write = phram_write; | |
1da177e4 | 116 | new->mtd.owner = THIS_MODULE; |
21c8db9e | 117 | new->mtd.type = MTD_RAM; |
663259a4 | 118 | new->mtd.erasesize = PAGE_SIZE; |
17ffc7ba | 119 | new->mtd.writesize = 1; |
1da177e4 LT |
120 | |
121 | ret = -EAGAIN; | |
ee0e87b1 | 122 | if (mtd_device_register(&new->mtd, NULL, 0)) { |
64da392a | 123 | pr_err("Failed to register new device\n"); |
1da177e4 LT |
124 | goto out2; |
125 | } | |
126 | ||
127 | list_add_tail(&new->list, &phram_list); | |
e5580fbe | 128 | return 0; |
1da177e4 LT |
129 | |
130 | out2: | |
131 | iounmap(new->mtd.priv); | |
132 | out1: | |
133 | kfree(new); | |
134 | out0: | |
135 | return ret; | |
136 | } | |
137 | ||
2a46f835 | 138 | static int parse_num64(uint64_t *num64, char *token) |
1da177e4 | 139 | { |
2a46f835 AS |
140 | size_t len; |
141 | int shift = 0; | |
142 | int ret; | |
143 | ||
144 | len = strlen(token); | |
1da177e4 | 145 | /* By dwmw2 editorial decree, "ki", "Mi" or "Gi" are to be used. */ |
2a46f835 AS |
146 | if (len > 2) { |
147 | if (token[len - 1] == 'i') { | |
148 | switch (token[len - 2]) { | |
149 | case 'G': | |
150 | shift += 10; | |
098d74b4 | 151 | /* fall through */ |
2a46f835 AS |
152 | case 'M': |
153 | shift += 10; | |
098d74b4 | 154 | /* fall through */ |
2a46f835 AS |
155 | case 'k': |
156 | shift += 10; | |
157 | token[len - 2] = 0; | |
158 | break; | |
159 | default: | |
160 | return -EINVAL; | |
161 | } | |
162 | } | |
1da177e4 | 163 | } |
1da177e4 | 164 | |
2a46f835 AS |
165 | ret = kstrtou64(token, 0, num64); |
166 | *num64 <<= shift; | |
1da177e4 | 167 | |
2a46f835 | 168 | return ret; |
1da177e4 LT |
169 | } |
170 | ||
171 | static int parse_name(char **pname, const char *token) | |
172 | { | |
173 | size_t len; | |
174 | char *name; | |
175 | ||
176 | len = strlen(token) + 1; | |
177 | if (len > 64) | |
178 | return -ENOSPC; | |
179 | ||
89384f64 | 180 | name = kstrdup(token, GFP_KERNEL); |
1da177e4 LT |
181 | if (!name) |
182 | return -ENOMEM; | |
183 | ||
1da177e4 LT |
184 | *pname = name; |
185 | return 0; | |
186 | } | |
187 | ||
663259a4 JE |
188 | |
189 | static inline void kill_final_newline(char *str) | |
190 | { | |
191 | char *newline = strrchr(str, '\n'); | |
c95777a4 | 192 | |
663259a4 JE |
193 | if (newline && !newline[1]) |
194 | *newline = 0; | |
195 | } | |
196 | ||
197 | ||
1da177e4 | 198 | #define parse_err(fmt, args...) do { \ |
64da392a MF |
199 | pr_err(fmt , ## args); \ |
200 | return 1; \ | |
1da177e4 LT |
201 | } while (0) |
202 | ||
6f6b9fee AS |
203 | #ifndef MODULE |
204 | static int phram_init_called; | |
b2a2a84d HF |
205 | /* |
206 | * This shall contain the module parameter if any. It is of the form: | |
207 | * - phram=<device>,<address>,<size> for module case | |
208 | * - phram.phram=<device>,<address>,<size> for built-in case | |
2a46f835 | 209 | * We leave 64 bytes for the device name, 20 for the address and 20 for the |
b2a2a84d HF |
210 | * size. |
211 | * Example: phram.phram=rootfs,0xa0000000,512Mi | |
212 | */ | |
6f6b9fee AS |
213 | static char phram_paramline[64 + 20 + 20]; |
214 | #endif | |
b2a2a84d | 215 | |
6f6b9fee | 216 | static int phram_setup(const char *val) |
1da177e4 | 217 | { |
2a46f835 | 218 | char buf[64 + 20 + 20], *str = buf; |
1da177e4 LT |
219 | char *token[3]; |
220 | char *name; | |
2a46f835 AS |
221 | uint64_t start; |
222 | uint64_t len; | |
1da177e4 LT |
223 | int i, ret; |
224 | ||
225 | if (strnlen(val, sizeof(buf)) >= sizeof(buf)) | |
226 | parse_err("parameter too long\n"); | |
227 | ||
228 | strcpy(str, val); | |
663259a4 | 229 | kill_final_newline(str); |
1da177e4 | 230 | |
c95777a4 | 231 | for (i = 0; i < 3; i++) |
1da177e4 LT |
232 | token[i] = strsep(&str, ","); |
233 | ||
234 | if (str) | |
235 | parse_err("too many arguments\n"); | |
236 | ||
237 | if (!token[2]) | |
238 | parse_err("not enough arguments\n"); | |
239 | ||
240 | ret = parse_name(&name, token[0]); | |
1da177e4 | 241 | if (ret) |
64da392a | 242 | return ret; |
1da177e4 | 243 | |
2a46f835 | 244 | ret = parse_num64(&start, token[1]); |
4f678a58 JJ |
245 | if (ret) { |
246 | kfree(name); | |
1da177e4 | 247 | parse_err("illegal start address\n"); |
4f678a58 | 248 | } |
1da177e4 | 249 | |
2a46f835 | 250 | ret = parse_num64(&len, token[2]); |
4f678a58 JJ |
251 | if (ret) { |
252 | kfree(name); | |
1da177e4 | 253 | parse_err("illegal device length\n"); |
4f678a58 | 254 | } |
1da177e4 | 255 | |
64da392a MF |
256 | ret = register_device(name, start, len); |
257 | if (!ret) | |
2a46f835 | 258 | pr_info("%s device: %#llx at %#llx\n", name, len, start); |
f17f12ce MK |
259 | else |
260 | kfree(name); | |
1da177e4 | 261 | |
64da392a | 262 | return ret; |
1da177e4 LT |
263 | } |
264 | ||
e4dca7b7 | 265 | static int phram_param_call(const char *val, const struct kernel_param *kp) |
b2a2a84d | 266 | { |
6f6b9fee AS |
267 | #ifdef MODULE |
268 | return phram_setup(val); | |
269 | #else | |
b2a2a84d | 270 | /* |
6f6b9fee AS |
271 | * If more parameters are later passed in via |
272 | * /sys/module/phram/parameters/phram | |
273 | * and init_phram() has already been called, | |
274 | * we can parse the argument now. | |
b2a2a84d | 275 | */ |
6f6b9fee AS |
276 | |
277 | if (phram_init_called) | |
278 | return phram_setup(val); | |
279 | ||
280 | /* | |
281 | * During early boot stage, we only save the parameters | |
282 | * here. We must parse them later: if the param passed | |
283 | * from kernel boot command line, phram_param_call() is | |
284 | * called so early that it is not possible to resolve | |
285 | * the device (even kmalloc() fails). Defer that work to | |
286 | * phram_setup(). | |
287 | */ | |
288 | ||
b2a2a84d HF |
289 | if (strlen(val) >= sizeof(phram_paramline)) |
290 | return -ENOSPC; | |
291 | strcpy(phram_paramline, val); | |
292 | ||
293 | return 0; | |
6f6b9fee | 294 | #endif |
b2a2a84d HF |
295 | } |
296 | ||
297 | module_param_call(phram, phram_param_call, NULL, NULL, 000); | |
f72561cf | 298 | MODULE_PARM_DESC(phram, "Memory region to map. \"phram=<name>,<start>,<length>\""); |
1da177e4 LT |
299 | |
300 | ||
301 | static int __init init_phram(void) | |
302 | { | |
6f6b9fee AS |
303 | int ret = 0; |
304 | ||
305 | #ifndef MODULE | |
b2a2a84d | 306 | if (phram_paramline[0]) |
6f6b9fee AS |
307 | ret = phram_setup(phram_paramline); |
308 | phram_init_called = 1; | |
309 | #endif | |
b2a2a84d | 310 | |
6f6b9fee | 311 | return ret; |
1da177e4 LT |
312 | } |
313 | ||
314 | static void __exit cleanup_phram(void) | |
315 | { | |
316 | unregister_devices(); | |
317 | } | |
318 | ||
319 | module_init(init_phram); | |
320 | module_exit(cleanup_phram); | |
321 | ||
322 | MODULE_LICENSE("GPL"); | |
2b54aaef | 323 | MODULE_AUTHOR("Joern Engel <joern@wh.fh-wedel.de>"); |
1da177e4 | 324 | MODULE_DESCRIPTION("MTD driver for physical RAM"); |