aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/nvram_64.c
blob: 0ed31f2204826e2fa68315bd5bfe7be3cf3b10ba (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
/*
 *  c 2001 PPC 64 Team, IBM Corp
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 * /dev/nvram driver for PPC64
 *
 * This perhaps should live in drivers/char
 *
 * TODO: Split the /dev/nvram part (that one can use
 *       drivers/char/generic_nvram.c) from the arch & partition
 *       parsing code.
 */

#include <linux/module.h>

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/fcntl.h>
#include <linux/nvram.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <asm/uaccess.h>
#include <asm/nvram.h>
#include <asm/rtas.h>
#include <asm/prom.h>
#include <asm/machdep.h>

#undef DEBUG_NVRAM

static struct nvram_partition * nvram_part;
static long nvram_error_log_index = -1;
static long nvram_error_log_size = 0;

struct err_log_info {
	int error_type;
	unsigned int seq_num;
};

static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin)
{
	int size;

	if (ppc_md.nvram_size == NULL)
		return -ENODEV;
	size = ppc_md.nvram_size();

	switch (origin) {
	case 1:
		offset += file->f_pos;
		break;
	case 2:
		offset += size;
		break;
	}
	if (offset < 0)
		return -EINVAL;
	file->f_pos = offset;
	return file->f_pos;
}


static ssize_t dev_nvram_read(struct file *file, char __user *buf,
			  size_t count, loff_t *ppos)
{
	ssize_t ret;
	char *tmp = NULL;
	ssize_t size;

	ret = -ENODEV;
	if (!ppc_md.nvram_size)
		goto out;

	ret = 0;
	size = ppc_md.nvram_size();
	if (*ppos >= size || size < 0)
		goto out;

	count = min_t(size_t, count, size - *ppos);
	count = min(count, PAGE_SIZE);

	ret = -ENOMEM;
	tmp = kmalloc(count, GFP_KERNEL);
	if (!tmp)
		goto out;

	ret = ppc_md.nvram_read(tmp, count, ppos);
	if (ret <= 0)
		goto out;

	if (copy_to_user(buf, tmp, ret))
		ret = -EFAULT;

out:
	kfree(tmp);
	return ret;

}

static ssize_t dev_nvram_write(struct file *file, const char __user *buf,
			  size_t count, loff_t *ppos)
{
	ssize_t ret;
	char *tmp = NULL;
	ssize_t size;

	ret = -ENODEV;
	if (!ppc_md.nvram_size)
		goto out;

	ret = 0;
	size = ppc_md.nvram_size();
	if (*ppos >= size || size < 0)
		goto out;

	count = min_t(size_t, count, size - *ppos);
	count = min(count, PAGE_SIZE);

	ret = -ENOMEM;
	tmp = kmalloc(count, GFP_KERNEL);
	if (!tmp)
		goto out;

	ret = -EFAULT;
	if (copy_from_user(tmp, buf, count))
		goto out;

	ret = ppc_md.nvram_write(tmp, count, ppos);

out:
	kfree(tmp);
	return ret;

}

static int dev_nvram_ioctl(struct inode *inode, struct file *file,
	unsigned int cmd, unsigned long arg)
{
	switch(cmd) {
#ifdef CONFIG_PPC_PMAC
	case OBSOLETE_PMAC_NVRAM_GET_OFFSET:
		printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n");
	case IOC_NVRAM_GET_OFFSET: {
		int part, offset;

		if (!machine_is(powermac))
			return -EINVAL;
		if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
			return -EFAULT;
		if (part < pmac_nvram_OF || part > pmac_nvram_NR)
			return -EINVAL;
		offset = pmac_get_partition(part);
		if (offset < 0)
			return offset;
		if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0)
			return -EFAULT;
		return 0;
	}
#endif /* CONFIG_PPC_PMAC */
	default:
		return -EINVAL;
	}
}

const struct file_operations nvram_fops = {
	.owner =	THIS_MODULE,
	.llseek =	dev_nvram_llseek,
	.read =		dev_nvram_read,
	.write =	dev_nvram_write,
	.ioctl =	dev_nvram_ioctl,
};

static struct miscdevice nvram_dev = {
	NVRAM_MINOR,
	"nvram",
	&nvram_fops
};


#ifdef DEBUG_NVRAM
static void nvram_print_partitions(char * label)
{
	struct list_head * p;
	struct nvram_partition * tmp_part;
	
	printk(KERN_WARNING "--------%s---------\n", label);
	printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n");
	list_for_each(p, &nvram_part->partition) {
		tmp_part = list_entry(p, struct nvram_partition, partition);
		printk(KERN_WARNING "%4d    \t%02x\t%02x\t%d\t%s\n",
		       tmp_part->index, tmp_part->header.signature,
		       tmp_part->header.checksum, tmp_part->header.length,
		       tmp_part->header.name);
	}
}
#endif


static int nvram_write_header(struct nvram_partition * part)
{
	loff_t tmp_index;
	int rc;
	
	tmp_index = part->index;
	rc = ppc_md.nvram_write((char *)&part->header, NVRAM_HEADER_LEN, &tmp_index); 

	return rc;
}


static unsigned char nvram_checksum(struct nvram_header *p)
{
	unsigned int c_sum, c_sum2;
	unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */
	c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5];

	/* The sum may have spilled into the 3rd byte.  Fold it back. */
	c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff;
	/* The sum cannot exceed 2 bytes.  Fold it into a checksum */
	c_sum2 = (c_sum >> 8) + (c_sum << 8);
	c_sum = ((c_sum + c_sum2) >> 8) & 0xff;
	return c_sum;
}


/*
 * Find an nvram partition, sig can be 0 for any
 * partition or name can be NULL for any name, else
 * tries to match both
 */
struct nvram_partition *nvram_find_partition(int sig, const char *name)
{
	struct nvram_partition * part;
	struct list_head * p;

	list_for_each(p, &nvram_part->partition) {
		part = list_entry(p, struct nvram_partition, partition);

		if (sig && part->header.signature != sig)
			continue;
		if (name && 0 != strncmp(name, part->header.name, 12))
			continue;
		return part; 
	}
	return NULL;
}
EXPORT_SYMBOL(nvram_find_partition);


static int nvram_remove_os_partition(void)
{
	struct list_head *i;
	struct list_head *j;
	struct nvram_partition * part;
	struct nvram_partition * cur_part;
	int rc;

	list_for_each(i, &nvram_part->partition) {
		part = list_entry(i, struct nvram_partition, partition);
		if (part->header.signature != NVRAM_SIG_OS)
			continue;
		
		/* Make os partition a free partition */
		part->header.signature = NVRAM_SIG_FREE;
		sprintf(part->header.name, "wwwwwwwwwwww");
		part->header.checksum = nvram_checksum(&part->header);

		/* Merge contiguous free partitions backwards */
		list_for_each_prev(j, &part->partition) {
			cur_part = list_entry(j, struct nvram_partition, partition);
			if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
				break;
			}
			
			part->header.length += cur_part->header.length;
			part->header.checksum = nvram_checksum(&part->header);
			part->index = cur_part->index;

			list_del(&cur_part->partition);
			kfree(cur_part);
			j = &part->partition; /* fixup our loop */
		}
		
		/* Merge contiguous free partitions forwards */
		list_for_each(j, &part->partition) {
			cur_part = list_entry(j, struct nvram_partition, partition);
			if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
				break;
			}

			part->header.length += cur_part->header.length;
			part->header.checksum = nvram_checksum(&part->header);

			list_del(&cur_part->partition);
			kfree(cur_part);
			j = &part->partition; /* fixup our loop */
		}
		
		rc = nvram_write_header(part);
		if (rc <= 0) {
			printk(KERN_ERR "nvram_remove_os_partition: nvram_write failed (%d)\n", rc);
			return rc;
		}

	}
	
	return 0;
}

/* nvram_create_os_partition
 *
 * Create a OS linux partition to buffer error logs.
 * Will create a partition starting at the first free
 * space found if space has enough room.
 */
static int nvram_create_os_partition(void)
{
	struct nvram_partition *part;
	struct nvram_partition *new_part;
	struct nvram_partition *free_part = NULL;
	int seq_init[2] = { 0, 0 };
	loff_t tmp_index;
	long size = 0;
	int rc;
	
	/* Find a free partition that will give us the maximum needed size 
	   If can't find one that will give us the minimum size needed */
	list_for_each_entry(part, &nvram_part->partition, partition) {
		if (part->header.signature != NVRAM_SIG_FREE)
			continue;

		if (part->header.length >= NVRAM_MAX_REQ) {
			size = NVRAM_MAX_REQ;
			free_part = part;
			break;
		}
		if (!size && part->header.length >= NVRAM_MIN_REQ) {
			size = NVRAM_MIN_REQ;
			free_part = part;
		}
	}
	if (!size)
		return -ENOSPC;
	
	/* Create our OS partition */
	new_part = kmalloc(sizeof(*new_part), GFP_KERNEL);
	if (!new_part) {
		printk(KERN_ERR "nvram_create_os_partition: kmalloc failed\n");
		return -ENOMEM;
	}

	new_part->index = free_part->index;
	new_part->header.signature = NVRAM_SIG_OS;
	new_part->header.length = size;
	strcpy(new_part->header.name, "ppc64,linux");
	new_part->header.checksum = nvram_checksum(&new_part->header);

	rc = nvram_write_header(new_part);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_create_os_partition: nvram_write_header \
				failed (%d)\n", rc);
		return rc;
	}

	/* make sure and initialize to zero the sequence number and the error
	   type logged */
	tmp_index = new_part->index + NVRAM_HEADER_LEN;
	rc = ppc_md.nvram_write((char *)&seq_init, sizeof(seq_init), &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_create_os_partition: nvram_write "
				"failed (%d)\n", rc);
		return rc;
	}
	
	nvram_error_log_index = new_part->index + NVRAM_HEADER_LEN;
	nvram_error_log_size = ((part->header.length - 1) *
				NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
	
	list_add_tail(&new_part->partition, &free_part->partition);

	if (free_part->header.length <= size) {
		list_del(&free_part->partition);
		kfree(free_part);
		return 0;
	} 

	/* Adjust the partition we stole the space from */
	free_part->index += size * NVRAM_BLOCK_LEN;
	free_part->header.length -= size;
	free_part->header.checksum = nvram_checksum(&free_part->header);
	
	rc = nvram_write_header(free_part);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_create_os_partition: nvram_write_header "
		       "failed (%d)\n", rc);
		return rc;
	}

	return 0;
}


/* nvram_setup_partition
 *
 * This will setup the partition we need for buffering the
 * error logs and cleanup partitions if needed.
 *
 * The general strategy is the following:
 * 1.) If there is ppc64,linux partition large enough then use it.
 * 2.) If there is not a ppc64,linux partition large enough, search
 * for a free partition that is large enough.
 * 3.) If there is not a free partition large enough remove 
 * _all_ OS partitions and consolidate the space.
 * 4.) Will first try getting a chunk that will satisfy the maximum
 * error log size (NVRAM_MAX_REQ).
 * 5.) If the max chunk cannot be allocated then try finding a chunk
 * that will satisfy the minum needed (NVRAM_MIN_REQ).
 */
static int nvram_setup_partition(void)
{
	struct list_head * p;
	struct nvram_partition * part;
	int rc;

	/* For now, we don't do any of this on pmac, until I
	 * have figured out if it's worth killing some unused stuffs
	 * in our nvram, as Apple defined partitions use pretty much
	 * all of the space
	 */
	if (machine_is(powermac))
		return -ENOSPC;

	/* see if we have an OS partition that meets our needs.
	   will try getting the max we need.  If not we'll delete
	   partitions and try again. */
	list_for_each(p, &nvram_part->partition) {
		part = list_entry(p, struct nvram_partition, partition);
		if (part->header.signature != NVRAM_SIG_OS)
			continue;

		if (strcmp(part->header.name, "ppc64,linux"))
			continue;

		if (part->header.length >= NVRAM_MIN_REQ) {
			/* found our partition */
			nvram_error_log_index = part->index + NVRAM_HEADER_LEN;
			nvram_error_log_size = ((part->header.length - 1) *
						NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
			return 0;
		}
	}
	
	/* try creating a partition with the free space we have */
	rc = nvram_create_os_partition();
	if (!rc) {
		return 0;
	}
		
	/* need to free up some space */
	rc = nvram_remove_os_partition();
	if (rc) {
		return rc;
	}
	
	/* create a partition in this new space */
	rc = nvram_create_os_partition();
	if (rc) {
		printk(KERN_ERR "nvram_create_os_partition: Could not find a "
		       "NVRAM partition large enough\n");
		return rc;
	}
	
	return 0;
}


static int nvram_scan_partitions(void)
{
	loff_t cur_index = 0;
	struct nvram_header phead;
	struct nvram_partition * tmp_part;
	unsigned char c_sum;
	char * header;
	int total_size;
	int err;

	if (ppc_md.nvram_size == NULL)
		return -ENODEV;
	total_size = ppc_md.nvram_size();
	
	header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL);
	if (!header) {
		printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n");
		return -ENOMEM;
	}

	while (cur_index < total_size) {

		err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index);
		if (err != NVRAM_HEADER_LEN) {
			printk(KERN_ERR "nvram_scan_partitions: Error parsing "
			       "nvram partitions\n");
			goto out;
		}

		cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */

		memcpy(&phead, header, NVRAM_HEADER_LEN);

		err = 0;
		c_sum = nvram_checksum(&phead);
		if (c_sum != phead.checksum) {
			printk(KERN_WARNING "WARNING: nvram partition checksum"
			       " was %02x, should be %02x!\n",
			       phead.checksum, c_sum);
			printk(KERN_WARNING "Terminating nvram partition scan\n");
			goto out;
		}
		if (!phead.length) {
			printk(KERN_WARNING "WARNING: nvram corruption "
			       "detected: 0-length partition\n");
			goto out;
		}
		tmp_part = (struct nvram_partition *)
			kmalloc(sizeof(struct nvram_partition), GFP_KERNEL);
		err = -ENOMEM;
		if (!tmp_part) {
			printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n");
			goto out;
		}
		
		memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN);
		tmp_part->index = cur_index;
		list_add_tail(&tmp_part->partition, &nvram_part->partition);
		
		cur_index += phead.length * NVRAM_BLOCK_LEN;
	}
	err = 0;

 out:
	kfree(header);
	return err;
}

static int __init nvram_init(void)
{
	int error;
	int rc;
	
	if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
		return  -ENODEV;

  	rc = misc_register(&nvram_dev);
	if (rc != 0) {
		printk(KERN_ERR "nvram_init: failed to register device\n");
		return rc;
	}
  	
  	/* initialize our anchor for the nvram partition list */
  	nvram_part = kmalloc(sizeof(struct nvram_partition), GFP_KERNEL);
  	if (!nvram_part) {
  		printk(KERN_ERR "nvram_init: Failed kmalloc\n");
  		return -ENOMEM;
  	}
  	INIT_LIST_HEAD(&nvram_part->partition);
  
  	/* Get all the NVRAM partitions */
  	error = nvram_scan_partitions();
  	if (error) {
  		printk(KERN_ERR "nvram_init: Failed nvram_scan_partitions\n");
  		return error;
  	}
  		
  	if(nvram_setup_partition()) 
  		printk(KERN_WARNING "nvram_init: Could not find nvram partition"
  		       " for nvram buffered error logging.\n");
  
#ifdef DEBUG_NVRAM
	nvram_print_partitions("NVRAM Partitions");
#endif

  	return rc;
}

void __exit nvram_cleanup(void)
{
        misc_deregister( &nvram_dev );
}


#ifdef CONFIG_PPC_PSERIES

/* nvram_write_error_log
 *
 * We need to buffer the error logs into nvram to ensure that we have
 * the failure information to decode.  If we have a severe error there
 * is no way to guarantee that the OS or the machine is in a state to
 * get back to user land and write the error to disk.  For example if
 * the SCSI device driver causes a Machine Check by writing to a bad
 * IO address, there is no way of guaranteeing that the device driver
 * is in any state that is would also be able to write the error data
 * captured to disk, thus we buffer it in NVRAM for analysis on the
 * next boot.
 *
 * In NVRAM the partition containing the error log buffer will looks like:
 * Header (in bytes):
 * +-----------+----------+--------+------------+------------------+
 * | signature | checksum | length | name       | data             |
 * |0          |1         |2      3|4         15|16        length-1|
 * +-----------+----------+--------+------------+------------------+
 *
 * The 'data' section would look like (in bytes):
 * +--------------+------------+-----------------------------------+
 * | event_logged | sequence # | error log                         |
 * |0            3|4          7|8            nvram_error_log_size-1|
 * +--------------+------------+-----------------------------------+
 *
 * event_logged: 0 if event has not been logged to syslog, 1 if it has
 * sequence #: The unique sequence # for each event. (until it wraps)
 * error log: The error log from event_scan
 */
int nvram_write_error_log(char * buff, int length,
                          unsigned int err_type, unsigned int error_log_cnt)
{
	int rc;
	loff_t tmp_index;
	struct err_log_info info;
	
	if (nvram_error_log_index == -1) {
		return -ESPIPE;
	}

	if (length > nvram_error_log_size) {
		length = nvram_error_log_size;
	}

	info.error_type = err_type;
	info.seq_num = error_log_cnt;

	tmp_index = nvram_error_log_index;

	rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
		return rc;
	}

	rc = ppc_md.nvram_write(buff, length, &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
		return rc;
	}
	
	return 0;
}

/* nvram_read_error_log
 *
 * Reads nvram for error log for at most 'length'
 */
int nvram_read_error_log(char * buff, int length,
                         unsigned int * err_type, unsigned int * error_log_cnt)
{
	int rc;
	loff_t tmp_index;
	struct err_log_info info;
	
	if (nvram_error_log_index == -1)
		return -1;

	if (length > nvram_error_log_size)
		length = nvram_error_log_size;

	tmp_index = nvram_error_log_index;

	rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
		return rc;
	}

	rc = ppc_md.nvram_read(buff, length, &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
		return rc;
	}

	*error_log_cnt = info.seq_num;
	*err_type = info.error_type;

	return 0;
}

/* This doesn't actually zero anything, but it sets the event_logged
 * word to tell that this event is safely in syslog.
 */
int nvram_clear_error_log(void)
{
	loff_t tmp_index;
	int clear_word = ERR_FLAG_ALREADY_LOGGED;
	int rc;

	tmp_index = nvram_error_log_index;
	
	rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index);
	if (rc <= 0) {
		printk(KERN_ERR "nvram_clear_error_log: Failed nvram_write (%d)\n", rc);
		return rc;
	}

	return 0;
}

#endif /* CONFIG_PPC_PSERIES */

module_init(nvram_init);
module_exit(nvram_cleanup);
MODULE_LICENSE("GPL");