Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * c 2001 PPC 64 Team, IBM Corp | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | * | |
9 | * /dev/nvram driver for PPC64 | |
10 | * | |
11 | * This perhaps should live in drivers/char | |
12 | * | |
13 | * TODO: Split the /dev/nvram part (that one can use | |
14 | * drivers/char/generic_nvram.c) from the arch & partition | |
15 | * parsing code. | |
16 | */ | |
17 | ||
18 | #include <linux/module.h> | |
19 | ||
20 | #include <linux/types.h> | |
21 | #include <linux/errno.h> | |
22 | #include <linux/fs.h> | |
23 | #include <linux/miscdevice.h> | |
24 | #include <linux/fcntl.h> | |
25 | #include <linux/nvram.h> | |
26 | #include <linux/init.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/spinlock.h> | |
29 | #include <asm/uaccess.h> | |
30 | #include <asm/nvram.h> | |
31 | #include <asm/rtas.h> | |
32 | #include <asm/prom.h> | |
33 | #include <asm/machdep.h> | |
1da177e4 LT |
34 | |
35 | #undef DEBUG_NVRAM | |
36 | ||
36673307 BH |
37 | #define NVRAM_HEADER_LEN sizeof(struct nvram_header) |
38 | #define NVRAM_BLOCK_LEN NVRAM_HEADER_LEN | |
74d51d02 BH |
39 | |
40 | /* If change this size, then change the size of NVNAME_LEN */ | |
41 | struct nvram_header { | |
42 | unsigned char signature; | |
43 | unsigned char checksum; | |
44 | unsigned short length; | |
6024ede9 | 45 | /* Terminating null required only for names < 12 chars. */ |
74d51d02 BH |
46 | char name[12]; |
47 | }; | |
48 | ||
49 | struct nvram_partition { | |
50 | struct list_head partition; | |
51 | struct nvram_header header; | |
52 | unsigned int index; | |
53 | }; | |
54 | ||
690d1a9b | 55 | static LIST_HEAD(nvram_partitions); |
1da177e4 LT |
56 | |
57 | static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin) | |
58 | { | |
59 | int size; | |
60 | ||
61 | if (ppc_md.nvram_size == NULL) | |
62 | return -ENODEV; | |
63 | size = ppc_md.nvram_size(); | |
64 | ||
65 | switch (origin) { | |
66 | case 1: | |
67 | offset += file->f_pos; | |
68 | break; | |
69 | case 2: | |
70 | offset += size; | |
71 | break; | |
72 | } | |
73 | if (offset < 0) | |
74 | return -EINVAL; | |
75 | file->f_pos = offset; | |
76 | return file->f_pos; | |
77 | } | |
78 | ||
79 | ||
80 | static ssize_t dev_nvram_read(struct file *file, char __user *buf, | |
81 | size_t count, loff_t *ppos) | |
82 | { | |
f9ce299f AB |
83 | ssize_t ret; |
84 | char *tmp = NULL; | |
85 | ssize_t size; | |
1da177e4 | 86 | |
f9ce299f AB |
87 | ret = -ENODEV; |
88 | if (!ppc_md.nvram_size) | |
89 | goto out; | |
90 | ||
91 | ret = 0; | |
1da177e4 | 92 | size = ppc_md.nvram_size(); |
f9ce299f AB |
93 | if (*ppos >= size || size < 0) |
94 | goto out; | |
1da177e4 | 95 | |
f9ce299f AB |
96 | count = min_t(size_t, count, size - *ppos); |
97 | count = min(count, PAGE_SIZE); | |
1da177e4 | 98 | |
f9ce299f AB |
99 | ret = -ENOMEM; |
100 | tmp = kmalloc(count, GFP_KERNEL); | |
101 | if (!tmp) | |
102 | goto out; | |
1da177e4 | 103 | |
f9ce299f AB |
104 | ret = ppc_md.nvram_read(tmp, count, ppos); |
105 | if (ret <= 0) | |
106 | goto out; | |
107 | ||
108 | if (copy_to_user(buf, tmp, ret)) | |
109 | ret = -EFAULT; | |
1da177e4 | 110 | |
f9ce299f AB |
111 | out: |
112 | kfree(tmp); | |
113 | return ret; | |
1da177e4 LT |
114 | |
115 | } | |
116 | ||
117 | static ssize_t dev_nvram_write(struct file *file, const char __user *buf, | |
f9ce299f | 118 | size_t count, loff_t *ppos) |
1da177e4 | 119 | { |
f9ce299f AB |
120 | ssize_t ret; |
121 | char *tmp = NULL; | |
122 | ssize_t size; | |
1da177e4 | 123 | |
f9ce299f AB |
124 | ret = -ENODEV; |
125 | if (!ppc_md.nvram_size) | |
126 | goto out; | |
127 | ||
128 | ret = 0; | |
1da177e4 | 129 | size = ppc_md.nvram_size(); |
f9ce299f AB |
130 | if (*ppos >= size || size < 0) |
131 | goto out; | |
1da177e4 | 132 | |
f9ce299f AB |
133 | count = min_t(size_t, count, size - *ppos); |
134 | count = min(count, PAGE_SIZE); | |
1da177e4 | 135 | |
f9ce299f AB |
136 | ret = -ENOMEM; |
137 | tmp = kmalloc(count, GFP_KERNEL); | |
138 | if (!tmp) | |
139 | goto out; | |
140 | ||
141 | ret = -EFAULT; | |
142 | if (copy_from_user(tmp, buf, count)) | |
143 | goto out; | |
144 | ||
145 | ret = ppc_md.nvram_write(tmp, count, ppos); | |
146 | ||
147 | out: | |
148 | kfree(tmp); | |
149 | return ret; | |
1da177e4 | 150 | |
1da177e4 LT |
151 | } |
152 | ||
3b03fecd TG |
153 | static long dev_nvram_ioctl(struct file *file, unsigned int cmd, |
154 | unsigned long arg) | |
1da177e4 LT |
155 | { |
156 | switch(cmd) { | |
157 | #ifdef CONFIG_PPC_PMAC | |
158 | case OBSOLETE_PMAC_NVRAM_GET_OFFSET: | |
159 | printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n"); | |
160 | case IOC_NVRAM_GET_OFFSET: { | |
161 | int part, offset; | |
162 | ||
e8222502 | 163 | if (!machine_is(powermac)) |
1da177e4 LT |
164 | return -EINVAL; |
165 | if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) | |
166 | return -EFAULT; | |
167 | if (part < pmac_nvram_OF || part > pmac_nvram_NR) | |
168 | return -EINVAL; | |
169 | offset = pmac_get_partition(part); | |
170 | if (offset < 0) | |
171 | return offset; | |
172 | if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) | |
173 | return -EFAULT; | |
174 | return 0; | |
175 | } | |
176 | #endif /* CONFIG_PPC_PMAC */ | |
af308377 SR |
177 | default: |
178 | return -EINVAL; | |
1da177e4 | 179 | } |
1da177e4 LT |
180 | } |
181 | ||
5dfe4c96 | 182 | const struct file_operations nvram_fops = { |
3b03fecd TG |
183 | .owner = THIS_MODULE, |
184 | .llseek = dev_nvram_llseek, | |
185 | .read = dev_nvram_read, | |
186 | .write = dev_nvram_write, | |
187 | .unlocked_ioctl = dev_nvram_ioctl, | |
1da177e4 LT |
188 | }; |
189 | ||
190 | static struct miscdevice nvram_dev = { | |
191 | NVRAM_MINOR, | |
192 | "nvram", | |
193 | &nvram_fops | |
194 | }; | |
195 | ||
196 | ||
197 | #ifdef DEBUG_NVRAM | |
32c105c3 | 198 | static void __init nvram_print_partitions(char * label) |
1da177e4 | 199 | { |
1da177e4 LT |
200 | struct nvram_partition * tmp_part; |
201 | ||
202 | printk(KERN_WARNING "--------%s---------\n", label); | |
203 | printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n"); | |
690d1a9b | 204 | list_for_each_entry(tmp_part, &nvram_partitions, partition) { |
6024ede9 | 205 | printk(KERN_WARNING "%4d \t%02x\t%02x\t%d\t%12s\n", |
1da177e4 LT |
206 | tmp_part->index, tmp_part->header.signature, |
207 | tmp_part->header.checksum, tmp_part->header.length, | |
208 | tmp_part->header.name); | |
209 | } | |
210 | } | |
211 | #endif | |
212 | ||
213 | ||
32c105c3 | 214 | static int __init nvram_write_header(struct nvram_partition * part) |
1da177e4 LT |
215 | { |
216 | loff_t tmp_index; | |
217 | int rc; | |
218 | ||
219 | tmp_index = part->index; | |
220 | rc = ppc_md.nvram_write((char *)&part->header, NVRAM_HEADER_LEN, &tmp_index); | |
221 | ||
222 | return rc; | |
223 | } | |
224 | ||
225 | ||
32c105c3 | 226 | static unsigned char __init nvram_checksum(struct nvram_header *p) |
1da177e4 LT |
227 | { |
228 | unsigned int c_sum, c_sum2; | |
229 | unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */ | |
230 | c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5]; | |
231 | ||
232 | /* The sum may have spilled into the 3rd byte. Fold it back. */ | |
233 | c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff; | |
234 | /* The sum cannot exceed 2 bytes. Fold it into a checksum */ | |
235 | c_sum2 = (c_sum >> 8) + (c_sum << 8); | |
236 | c_sum = ((c_sum + c_sum2) >> 8) & 0xff; | |
237 | return c_sum; | |
238 | } | |
239 | ||
0f4ac132 JK |
240 | /* |
241 | * Per the criteria passed via nvram_remove_partition(), should this | |
242 | * partition be removed? 1=remove, 0=keep | |
243 | */ | |
244 | static int nvram_can_remove_partition(struct nvram_partition *part, | |
245 | const char *name, int sig, const char *exceptions[]) | |
246 | { | |
247 | if (part->header.signature != sig) | |
248 | return 0; | |
249 | if (name) { | |
250 | if (strncmp(name, part->header.name, 12)) | |
251 | return 0; | |
252 | } else if (exceptions) { | |
253 | const char **except; | |
254 | for (except = exceptions; *except; except++) { | |
255 | if (!strncmp(*except, part->header.name, 12)) | |
256 | return 0; | |
257 | } | |
258 | } | |
259 | return 1; | |
260 | } | |
261 | ||
fa2b4e54 BH |
262 | /** |
263 | * nvram_remove_partition - Remove one or more partitions in nvram | |
264 | * @name: name of the partition to remove, or NULL for a | |
265 | * signature only match | |
266 | * @sig: signature of the partition(s) to remove | |
0f4ac132 JK |
267 | * @exceptions: When removing all partitions with a matching signature, |
268 | * leave these alone. | |
fa2b4e54 BH |
269 | */ |
270 | ||
0f4ac132 JK |
271 | int __init nvram_remove_partition(const char *name, int sig, |
272 | const char *exceptions[]) | |
1da177e4 | 273 | { |
fa2b4e54 | 274 | struct nvram_partition *part, *prev, *tmp; |
1da177e4 LT |
275 | int rc; |
276 | ||
690d1a9b | 277 | list_for_each_entry(part, &nvram_partitions, partition) { |
0f4ac132 | 278 | if (!nvram_can_remove_partition(part, name, sig, exceptions)) |
fa2b4e54 BH |
279 | continue; |
280 | ||
281 | /* Make partition a free partition */ | |
1da177e4 | 282 | part->header.signature = NVRAM_SIG_FREE; |
6024ede9 | 283 | strncpy(part->header.name, "wwwwwwwwwwww", 12); |
1da177e4 | 284 | part->header.checksum = nvram_checksum(&part->header); |
1da177e4 LT |
285 | rc = nvram_write_header(part); |
286 | if (rc <= 0) { | |
fa2b4e54 | 287 | printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); |
1da177e4 LT |
288 | return rc; |
289 | } | |
fa2b4e54 | 290 | } |
1da177e4 | 291 | |
fa2b4e54 BH |
292 | /* Merge contiguous ones */ |
293 | prev = NULL; | |
690d1a9b | 294 | list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) { |
fa2b4e54 BH |
295 | if (part->header.signature != NVRAM_SIG_FREE) { |
296 | prev = NULL; | |
297 | continue; | |
298 | } | |
299 | if (prev) { | |
300 | prev->header.length += part->header.length; | |
301 | prev->header.checksum = nvram_checksum(&part->header); | |
302 | rc = nvram_write_header(part); | |
303 | if (rc <= 0) { | |
304 | printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); | |
305 | return rc; | |
306 | } | |
307 | list_del(&part->partition); | |
308 | kfree(part); | |
309 | } else | |
310 | prev = part; | |
1da177e4 LT |
311 | } |
312 | ||
313 | return 0; | |
314 | } | |
315 | ||
4e7c77a3 BH |
316 | /** |
317 | * nvram_create_partition - Create a partition in nvram | |
318 | * @name: name of the partition to create | |
319 | * @sig: signature of the partition to create | |
36673307 | 320 | * @req_size: size of data to allocate in bytes |
4e7c77a3 | 321 | * @min_size: minimum acceptable size (0 means req_size) |
e49e2e87 BH |
322 | * |
323 | * Returns a negative error code or a positive nvram index | |
324 | * of the beginning of the data area of the newly created | |
325 | * partition. If you provided a min_size smaller than req_size | |
326 | * you need to query for the actual size yourself after the | |
327 | * call using nvram_partition_get_size(). | |
1da177e4 | 328 | */ |
edc79a2f BH |
329 | loff_t __init nvram_create_partition(const char *name, int sig, |
330 | int req_size, int min_size) | |
1da177e4 | 331 | { |
a341ad97 AB |
332 | struct nvram_partition *part; |
333 | struct nvram_partition *new_part; | |
0339ad77 | 334 | struct nvram_partition *free_part = NULL; |
cef0d5ad | 335 | static char nv_init_vals[16]; |
1da177e4 LT |
336 | loff_t tmp_index; |
337 | long size = 0; | |
338 | int rc; | |
4e7c77a3 | 339 | |
36673307 BH |
340 | /* Convert sizes from bytes to blocks */ |
341 | req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; | |
342 | min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; | |
343 | ||
4e7c77a3 BH |
344 | /* If no minimum size specified, make it the same as the |
345 | * requested size | |
346 | */ | |
347 | if (min_size == 0) | |
348 | min_size = req_size; | |
e49e2e87 BH |
349 | if (min_size > req_size) |
350 | return -EINVAL; | |
4e7c77a3 | 351 | |
36673307 BH |
352 | /* Now add one block to each for the header */ |
353 | req_size += 1; | |
354 | min_size += 1; | |
355 | ||
1da177e4 LT |
356 | /* Find a free partition that will give us the maximum needed size |
357 | If can't find one that will give us the minimum size needed */ | |
690d1a9b | 358 | list_for_each_entry(part, &nvram_partitions, partition) { |
1da177e4 LT |
359 | if (part->header.signature != NVRAM_SIG_FREE) |
360 | continue; | |
361 | ||
4e7c77a3 BH |
362 | if (part->header.length >= req_size) { |
363 | size = req_size; | |
1da177e4 LT |
364 | free_part = part; |
365 | break; | |
366 | } | |
4e7c77a3 BH |
367 | if (part->header.length > size && |
368 | part->header.length >= min_size) { | |
369 | size = part->header.length; | |
1da177e4 LT |
370 | free_part = part; |
371 | } | |
372 | } | |
0339ad77 | 373 | if (!size) |
1da177e4 | 374 | return -ENOSPC; |
1da177e4 LT |
375 | |
376 | /* Create our OS partition */ | |
0339ad77 | 377 | new_part = kmalloc(sizeof(*new_part), GFP_KERNEL); |
1da177e4 | 378 | if (!new_part) { |
e49e2e87 | 379 | pr_err("nvram_create_os_partition: kmalloc failed\n"); |
1da177e4 LT |
380 | return -ENOMEM; |
381 | } | |
382 | ||
383 | new_part->index = free_part->index; | |
4e7c77a3 | 384 | new_part->header.signature = sig; |
1da177e4 | 385 | new_part->header.length = size; |
4e7c77a3 | 386 | strncpy(new_part->header.name, name, 12); |
1da177e4 LT |
387 | new_part->header.checksum = nvram_checksum(&new_part->header); |
388 | ||
389 | rc = nvram_write_header(new_part); | |
390 | if (rc <= 0) { | |
e49e2e87 BH |
391 | pr_err("nvram_create_os_partition: nvram_write_header " |
392 | "failed (%d)\n", rc); | |
1da177e4 LT |
393 | return rc; |
394 | } | |
e49e2e87 BH |
395 | list_add_tail(&new_part->partition, &free_part->partition); |
396 | ||
397 | /* Adjust or remove the partition we stole the space from */ | |
398 | if (free_part->header.length > size) { | |
399 | free_part->index += size * NVRAM_BLOCK_LEN; | |
400 | free_part->header.length -= size; | |
401 | free_part->header.checksum = nvram_checksum(&free_part->header); | |
402 | rc = nvram_write_header(free_part); | |
403 | if (rc <= 0) { | |
404 | pr_err("nvram_create_os_partition: nvram_write_header " | |
405 | "failed (%d)\n", rc); | |
406 | return rc; | |
407 | } | |
408 | } else { | |
409 | list_del(&free_part->partition); | |
410 | kfree(free_part); | |
411 | } | |
1da177e4 | 412 | |
e49e2e87 | 413 | /* Clear the new partition */ |
cef0d5ad BH |
414 | for (tmp_index = new_part->index + NVRAM_HEADER_LEN; |
415 | tmp_index < ((size - 1) * NVRAM_BLOCK_LEN); | |
416 | tmp_index += NVRAM_BLOCK_LEN) { | |
417 | rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index); | |
418 | if (rc <= 0) { | |
419 | pr_err("nvram_create_partition: nvram_write failed (%d)\n", rc); | |
420 | return rc; | |
421 | } | |
1da177e4 LT |
422 | } |
423 | ||
e49e2e87 BH |
424 | return new_part->index + NVRAM_HEADER_LEN; |
425 | } | |
1da177e4 | 426 | |
e49e2e87 BH |
427 | /** |
428 | * nvram_get_partition_size - Get the data size of an nvram partition | |
429 | * @data_index: This is the offset of the start of the data of | |
430 | * the partition. The same value that is returned by | |
431 | * nvram_create_partition(). | |
432 | */ | |
edc79a2f | 433 | int nvram_get_partition_size(loff_t data_index) |
e49e2e87 BH |
434 | { |
435 | struct nvram_partition *part; | |
1da177e4 | 436 | |
690d1a9b | 437 | list_for_each_entry(part, &nvram_partitions, partition) { |
e49e2e87 BH |
438 | if (part->index + NVRAM_HEADER_LEN == data_index) |
439 | return (part->header.length - 1) * NVRAM_BLOCK_LEN; | |
1da177e4 | 440 | } |
e49e2e87 | 441 | return -1; |
1da177e4 LT |
442 | } |
443 | ||
444 | ||
cf5cbf9f BH |
445 | /** |
446 | * nvram_find_partition - Find an nvram partition by signature and name | |
447 | * @name: Name of the partition or NULL for any name | |
448 | * @sig: Signature to test against | |
449 | * @out_size: if non-NULL, returns the size of the data part of the partition | |
450 | */ | |
451 | loff_t nvram_find_partition(const char *name, int sig, int *out_size) | |
452 | { | |
453 | struct nvram_partition *p; | |
454 | ||
690d1a9b | 455 | list_for_each_entry(p, &nvram_partitions, partition) { |
cf5cbf9f BH |
456 | if (p->header.signature == sig && |
457 | (!name || !strncmp(p->header.name, name, 12))) { | |
458 | if (out_size) | |
459 | *out_size = (p->header.length - 1) * | |
460 | NVRAM_BLOCK_LEN; | |
461 | return p->index + NVRAM_HEADER_LEN; | |
462 | } | |
463 | } | |
464 | return 0; | |
465 | } | |
466 | ||
edc79a2f | 467 | int __init nvram_scan_partitions(void) |
1da177e4 LT |
468 | { |
469 | loff_t cur_index = 0; | |
470 | struct nvram_header phead; | |
471 | struct nvram_partition * tmp_part; | |
472 | unsigned char c_sum; | |
473 | char * header; | |
474 | int total_size; | |
475 | int err; | |
476 | ||
edc79a2f | 477 | if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) |
1da177e4 LT |
478 | return -ENODEV; |
479 | total_size = ppc_md.nvram_size(); | |
480 | ||
5cbded58 | 481 | header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL); |
1da177e4 LT |
482 | if (!header) { |
483 | printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n"); | |
484 | return -ENOMEM; | |
485 | } | |
486 | ||
487 | while (cur_index < total_size) { | |
488 | ||
489 | err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index); | |
490 | if (err != NVRAM_HEADER_LEN) { | |
491 | printk(KERN_ERR "nvram_scan_partitions: Error parsing " | |
492 | "nvram partitions\n"); | |
493 | goto out; | |
494 | } | |
495 | ||
496 | cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */ | |
497 | ||
498 | memcpy(&phead, header, NVRAM_HEADER_LEN); | |
499 | ||
500 | err = 0; | |
501 | c_sum = nvram_checksum(&phead); | |
502 | if (c_sum != phead.checksum) { | |
503 | printk(KERN_WARNING "WARNING: nvram partition checksum" | |
504 | " was %02x, should be %02x!\n", | |
505 | phead.checksum, c_sum); | |
506 | printk(KERN_WARNING "Terminating nvram partition scan\n"); | |
507 | goto out; | |
508 | } | |
509 | if (!phead.length) { | |
510 | printk(KERN_WARNING "WARNING: nvram corruption " | |
511 | "detected: 0-length partition\n"); | |
512 | goto out; | |
513 | } | |
514 | tmp_part = (struct nvram_partition *) | |
515 | kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); | |
516 | err = -ENOMEM; | |
517 | if (!tmp_part) { | |
518 | printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n"); | |
519 | goto out; | |
520 | } | |
521 | ||
522 | memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN); | |
523 | tmp_part->index = cur_index; | |
690d1a9b | 524 | list_add_tail(&tmp_part->partition, &nvram_partitions); |
1da177e4 LT |
525 | |
526 | cur_index += phead.length * NVRAM_BLOCK_LEN; | |
527 | } | |
528 | err = 0; | |
529 | ||
edc79a2f BH |
530 | #ifdef DEBUG_NVRAM |
531 | nvram_print_partitions("NVRAM Partitions"); | |
532 | #endif | |
533 | ||
1da177e4 LT |
534 | out: |
535 | kfree(header); | |
536 | return err; | |
537 | } | |
538 | ||
539 | static int __init nvram_init(void) | |
540 | { | |
1da177e4 LT |
541 | int rc; |
542 | ||
578914cf BH |
543 | BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16); |
544 | ||
1da177e4 LT |
545 | if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) |
546 | return -ENODEV; | |
547 | ||
548 | rc = misc_register(&nvram_dev); | |
549 | if (rc != 0) { | |
550 | printk(KERN_ERR "nvram_init: failed to register device\n"); | |
551 | return rc; | |
552 | } | |
553 | ||
1da177e4 LT |
554 | return rc; |
555 | } | |
556 | ||
557 | void __exit nvram_cleanup(void) | |
558 | { | |
559 | misc_deregister( &nvram_dev ); | |
560 | } | |
561 | ||
1da177e4 LT |
562 | module_init(nvram_init); |
563 | module_exit(nvram_cleanup); | |
564 | MODULE_LICENSE("GPL"); |