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 | |
1da177e4 LT |
20 | #include <asm/io.h> |
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 | ||
36 | ||
1da177e4 LT |
37 | static int phram_erase(struct mtd_info *mtd, struct erase_info *instr) |
38 | { | |
39 | u_char *start = mtd->priv; | |
40 | ||
41 | if (instr->addr + instr->len > mtd->size) | |
42 | return -EINVAL; | |
e5580fbe | 43 | |
1da177e4 LT |
44 | memset(start + instr->addr, 0xff, instr->len); |
45 | ||
e5580fbe | 46 | /* This'll catch a few races. Free the thing before returning :) |
1da177e4 LT |
47 | * I don't feel at all ashamed. This kind of thing is possible anyway |
48 | * with flash, but unlikely. | |
49 | */ | |
50 | ||
51 | instr->state = MTD_ERASE_DONE; | |
52 | ||
53 | mtd_erase_callback(instr); | |
54 | ||
55 | return 0; | |
56 | } | |
57 | ||
58 | static int phram_point(struct mtd_info *mtd, loff_t from, size_t len, | |
a98889f3 | 59 | size_t *retlen, void **virt, resource_size_t *phys) |
1da177e4 | 60 | { |
1da177e4 LT |
61 | if (from + len > mtd->size) |
62 | return -EINVAL; | |
e5580fbe | 63 | |
a98889f3 JH |
64 | /* can we return a physical address with this driver? */ |
65 | if (phys) | |
66 | return -EINVAL; | |
67 | ||
68 | *virt = mtd->priv + from; | |
1da177e4 LT |
69 | *retlen = len; |
70 | return 0; | |
71 | } | |
72 | ||
a98889f3 | 73 | static void phram_unpoint(struct mtd_info *mtd, loff_t from, size_t len) |
1da177e4 LT |
74 | { |
75 | } | |
76 | ||
77 | static int phram_read(struct mtd_info *mtd, loff_t from, size_t len, | |
78 | size_t *retlen, u_char *buf) | |
79 | { | |
80 | u_char *start = mtd->priv; | |
81 | ||
663259a4 | 82 | if (from >= mtd->size) |
1da177e4 | 83 | return -EINVAL; |
663259a4 JE |
84 | |
85 | if (len > mtd->size - from) | |
86 | len = mtd->size - from; | |
e5580fbe | 87 | |
1da177e4 LT |
88 | memcpy(buf, start + from, len); |
89 | ||
90 | *retlen = len; | |
91 | return 0; | |
92 | } | |
93 | ||
94 | static int phram_write(struct mtd_info *mtd, loff_t to, size_t len, | |
95 | size_t *retlen, const u_char *buf) | |
96 | { | |
97 | u_char *start = mtd->priv; | |
98 | ||
663259a4 | 99 | if (to >= mtd->size) |
1da177e4 | 100 | return -EINVAL; |
663259a4 JE |
101 | |
102 | if (len > mtd->size - to) | |
103 | len = mtd->size - to; | |
e5580fbe | 104 | |
1da177e4 LT |
105 | memcpy(start + to, buf, len); |
106 | ||
107 | *retlen = len; | |
108 | return 0; | |
109 | } | |
110 | ||
111 | ||
112 | ||
113 | static void unregister_devices(void) | |
114 | { | |
d30f11d2 | 115 | struct phram_mtd_list *this, *safe; |
1da177e4 | 116 | |
d30f11d2 | 117 | list_for_each_entry_safe(this, safe, &phram_list, list) { |
1da177e4 LT |
118 | del_mtd_device(&this->mtd); |
119 | iounmap(this->mtd.priv); | |
120 | kfree(this); | |
121 | } | |
122 | } | |
123 | ||
124 | static int register_device(char *name, unsigned long start, unsigned long len) | |
125 | { | |
126 | struct phram_mtd_list *new; | |
127 | int ret = -ENOMEM; | |
128 | ||
95b93a0c | 129 | new = kzalloc(sizeof(*new), GFP_KERNEL); |
1da177e4 LT |
130 | if (!new) |
131 | goto out0; | |
132 | ||
1da177e4 LT |
133 | ret = -EIO; |
134 | new->mtd.priv = ioremap(start, len); | |
135 | if (!new->mtd.priv) { | |
64da392a | 136 | pr_err("ioremap failed\n"); |
1da177e4 LT |
137 | goto out1; |
138 | } | |
139 | ||
140 | ||
141 | new->mtd.name = name; | |
142 | new->mtd.size = len; | |
a6c591ed | 143 | new->mtd.flags = MTD_CAP_RAM; |
1da177e4 LT |
144 | new->mtd.erase = phram_erase; |
145 | new->mtd.point = phram_point; | |
146 | new->mtd.unpoint = phram_unpoint; | |
147 | new->mtd.read = phram_read; | |
148 | new->mtd.write = phram_write; | |
149 | new->mtd.owner = THIS_MODULE; | |
21c8db9e | 150 | new->mtd.type = MTD_RAM; |
663259a4 | 151 | new->mtd.erasesize = PAGE_SIZE; |
17ffc7ba | 152 | new->mtd.writesize = 1; |
1da177e4 LT |
153 | |
154 | ret = -EAGAIN; | |
155 | if (add_mtd_device(&new->mtd)) { | |
64da392a | 156 | pr_err("Failed to register new device\n"); |
1da177e4 LT |
157 | goto out2; |
158 | } | |
159 | ||
160 | list_add_tail(&new->list, &phram_list); | |
e5580fbe | 161 | return 0; |
1da177e4 LT |
162 | |
163 | out2: | |
164 | iounmap(new->mtd.priv); | |
165 | out1: | |
166 | kfree(new); | |
167 | out0: | |
168 | return ret; | |
169 | } | |
170 | ||
171 | static int ustrtoul(const char *cp, char **endp, unsigned int base) | |
172 | { | |
173 | unsigned long result = simple_strtoul(cp, endp, base); | |
174 | ||
175 | switch (**endp) { | |
176 | case 'G': | |
177 | result *= 1024; | |
178 | case 'M': | |
179 | result *= 1024; | |
180 | case 'k': | |
181 | result *= 1024; | |
182 | /* By dwmw2 editorial decree, "ki", "Mi" or "Gi" are to be used. */ | |
183 | if ((*endp)[1] == 'i') | |
184 | (*endp) += 2; | |
185 | } | |
186 | return result; | |
187 | } | |
188 | ||
189 | static int parse_num32(uint32_t *num32, const char *token) | |
190 | { | |
191 | char *endp; | |
192 | unsigned long n; | |
193 | ||
194 | n = ustrtoul(token, &endp, 0); | |
195 | if (*endp) | |
196 | return -EINVAL; | |
197 | ||
198 | *num32 = n; | |
199 | return 0; | |
200 | } | |
201 | ||
202 | static int parse_name(char **pname, const char *token) | |
203 | { | |
204 | size_t len; | |
205 | char *name; | |
206 | ||
207 | len = strlen(token) + 1; | |
208 | if (len > 64) | |
209 | return -ENOSPC; | |
210 | ||
211 | name = kmalloc(len, GFP_KERNEL); | |
212 | if (!name) | |
213 | return -ENOMEM; | |
214 | ||
215 | strcpy(name, token); | |
216 | ||
217 | *pname = name; | |
218 | return 0; | |
219 | } | |
220 | ||
663259a4 JE |
221 | |
222 | static inline void kill_final_newline(char *str) | |
223 | { | |
224 | char *newline = strrchr(str, '\n'); | |
225 | if (newline && !newline[1]) | |
226 | *newline = 0; | |
227 | } | |
228 | ||
229 | ||
1da177e4 | 230 | #define parse_err(fmt, args...) do { \ |
64da392a MF |
231 | pr_err(fmt , ## args); \ |
232 | return 1; \ | |
1da177e4 LT |
233 | } while (0) |
234 | ||
235 | static int phram_setup(const char *val, struct kernel_param *kp) | |
236 | { | |
237 | char buf[64+12+12], *str = buf; | |
238 | char *token[3]; | |
239 | char *name; | |
240 | uint32_t start; | |
241 | uint32_t len; | |
242 | int i, ret; | |
243 | ||
244 | if (strnlen(val, sizeof(buf)) >= sizeof(buf)) | |
245 | parse_err("parameter too long\n"); | |
246 | ||
247 | strcpy(str, val); | |
663259a4 | 248 | kill_final_newline(str); |
1da177e4 LT |
249 | |
250 | for (i=0; i<3; i++) | |
251 | token[i] = strsep(&str, ","); | |
252 | ||
253 | if (str) | |
254 | parse_err("too many arguments\n"); | |
255 | ||
256 | if (!token[2]) | |
257 | parse_err("not enough arguments\n"); | |
258 | ||
259 | ret = parse_name(&name, token[0]); | |
1da177e4 | 260 | if (ret) |
64da392a | 261 | return ret; |
1da177e4 LT |
262 | |
263 | ret = parse_num32(&start, token[1]); | |
4f678a58 JJ |
264 | if (ret) { |
265 | kfree(name); | |
1da177e4 | 266 | parse_err("illegal start address\n"); |
4f678a58 | 267 | } |
1da177e4 LT |
268 | |
269 | ret = parse_num32(&len, token[2]); | |
4f678a58 JJ |
270 | if (ret) { |
271 | kfree(name); | |
1da177e4 | 272 | parse_err("illegal device length\n"); |
4f678a58 | 273 | } |
1da177e4 | 274 | |
64da392a MF |
275 | ret = register_device(name, start, len); |
276 | if (!ret) | |
277 | pr_info("%s device: %#x at %#x\n", name, len, start); | |
1da177e4 | 278 | |
64da392a | 279 | return ret; |
1da177e4 LT |
280 | } |
281 | ||
282 | module_param_call(phram, phram_setup, NULL, NULL, 000); | |
f72561cf | 283 | MODULE_PARM_DESC(phram, "Memory region to map. \"phram=<name>,<start>,<length>\""); |
1da177e4 LT |
284 | |
285 | ||
286 | static int __init init_phram(void) | |
287 | { | |
288 | return 0; | |
289 | } | |
290 | ||
291 | static void __exit cleanup_phram(void) | |
292 | { | |
293 | unregister_devices(); | |
294 | } | |
295 | ||
296 | module_init(init_phram); | |
297 | module_exit(cleanup_phram); | |
298 | ||
299 | MODULE_LICENSE("GPL"); | |
2b54aaef | 300 | MODULE_AUTHOR("Joern Engel <joern@wh.fh-wedel.de>"); |
1da177e4 | 301 | MODULE_DESCRIPTION("MTD driver for physical RAM"); |