Free Electrons

Embedded Linux Experts

  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
/*
 * Intel e7xxx Memory Controller kernel module
 * (C) 2003 Linux Networx (http://lnxi.com)
 * This file may be distributed under the terms of the
 * GNU General Public License.
 *
 * See "enum e7xxx_chips" below for supported chipsets
 *
 * Written by Thayne Harbaugh
 * Based on work by Dan Hollis <goemon at anime dot net> and others.
 *	http://www.anime.net/~goemon/linux-ecc/
 *
 * Contributors:
 *	Eric Biederman (Linux Networx)
 *	Tom Zimmerman (Linux Networx)
 *	Jim Garlick (Lawrence Livermore National Labs)
 *	Dave Peterson (Lawrence Livermore National Labs)
 *	That One Guy (Some other place)
 *	Wang Zhenyu (intel.com)
 *
 * $Id: edac_e7xxx.c,v 1.5.2.9 2005/10/05 00:43:44 dsp_llnl Exp $
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/slab.h>
#include <linux/edac.h>
#include "edac_core.h"

#define	E7XXX_REVISION " Ver: 2.0.2 " __DATE__
#define	EDAC_MOD_STR	"e7xxx_edac"

#define e7xxx_printk(level, fmt, arg...) \
	edac_printk(level, "e7xxx", fmt, ##arg)

#define e7xxx_mc_printk(mci, level, fmt, arg...) \
	edac_mc_chipset_printk(mci, level, "e7xxx", fmt, ##arg)

#ifndef PCI_DEVICE_ID_INTEL_7205_0
#define PCI_DEVICE_ID_INTEL_7205_0	0x255d
#endif				/* PCI_DEVICE_ID_INTEL_7205_0 */

#ifndef PCI_DEVICE_ID_INTEL_7205_1_ERR
#define PCI_DEVICE_ID_INTEL_7205_1_ERR	0x2551
#endif				/* PCI_DEVICE_ID_INTEL_7205_1_ERR */

#ifndef PCI_DEVICE_ID_INTEL_7500_0
#define PCI_DEVICE_ID_INTEL_7500_0	0x2540
#endif				/* PCI_DEVICE_ID_INTEL_7500_0 */

#ifndef PCI_DEVICE_ID_INTEL_7500_1_ERR
#define PCI_DEVICE_ID_INTEL_7500_1_ERR	0x2541
#endif				/* PCI_DEVICE_ID_INTEL_7500_1_ERR */

#ifndef PCI_DEVICE_ID_INTEL_7501_0
#define PCI_DEVICE_ID_INTEL_7501_0	0x254c
#endif				/* PCI_DEVICE_ID_INTEL_7501_0 */

#ifndef PCI_DEVICE_ID_INTEL_7501_1_ERR
#define PCI_DEVICE_ID_INTEL_7501_1_ERR	0x2541
#endif				/* PCI_DEVICE_ID_INTEL_7501_1_ERR */

#ifndef PCI_DEVICE_ID_INTEL_7505_0
#define PCI_DEVICE_ID_INTEL_7505_0	0x2550
#endif				/* PCI_DEVICE_ID_INTEL_7505_0 */

#ifndef PCI_DEVICE_ID_INTEL_7505_1_ERR
#define PCI_DEVICE_ID_INTEL_7505_1_ERR	0x2551
#endif				/* PCI_DEVICE_ID_INTEL_7505_1_ERR */

#define E7XXX_NR_CSROWS		8	/* number of csrows */
#define E7XXX_NR_DIMMS		8	/* FIXME - is this correct? */

/* E7XXX register addresses - device 0 function 0 */
#define E7XXX_DRB		0x60	/* DRAM row boundary register (8b) */
#define E7XXX_DRA		0x70	/* DRAM row attribute register (8b) */
					/*
					 * 31   Device width row 7 0=x8 1=x4
					 * 27   Device width row 6
					 * 23   Device width row 5
					 * 19   Device width row 4
					 * 15   Device width row 3
					 * 11   Device width row 2
					 *  7   Device width row 1
					 *  3   Device width row 0
					 */
#define E7XXX_DRC		0x7C	/* DRAM controller mode reg (32b) */
					/*
					 * 22    Number channels 0=1,1=2
					 * 19:18 DRB Granularity 32/64MB
					 */
#define E7XXX_TOLM		0xC4	/* DRAM top of low memory reg (16b) */
#define E7XXX_REMAPBASE		0xC6	/* DRAM remap base address reg (16b) */
#define E7XXX_REMAPLIMIT	0xC8	/* DRAM remap limit address reg (16b) */

/* E7XXX register addresses - device 0 function 1 */
#define E7XXX_DRAM_FERR		0x80	/* DRAM first error register (8b) */
#define E7XXX_DRAM_NERR		0x82	/* DRAM next error register (8b) */
#define E7XXX_DRAM_CELOG_ADD	0xA0	/* DRAM first correctable memory */
					/*     error address register (32b) */
					/*
					 * 31:28 Reserved
					 * 27:6  CE address (4k block 33:12)
					 *  5:0  Reserved
					 */
#define E7XXX_DRAM_UELOG_ADD	0xB0	/* DRAM first uncorrectable memory */
					/*     error address register (32b) */
					/*
					 * 31:28 Reserved
					 * 27:6  CE address (4k block 33:12)
					 *  5:0  Reserved
					 */
#define E7XXX_DRAM_CELOG_SYNDROME 0xD0	/* DRAM first correctable memory */
					/*     error syndrome register (16b) */

enum e7xxx_chips {
	E7500 = 0,
	E7501,
	E7505,
	E7205,
};

struct e7xxx_pvt {
	struct pci_dev *bridge_ck;
	u32 tolm;
	u32 remapbase;
	u32 remaplimit;
	const struct e7xxx_dev_info *dev_info;
};

struct e7xxx_dev_info {
	u16 err_dev;
	const char *ctl_name;
};

struct e7xxx_error_info {
	u8 dram_ferr;
	u8 dram_nerr;
	u32 dram_celog_add;
	u16 dram_celog_syndrome;
	u32 dram_uelog_add;
};

static struct edac_pci_ctl_info *e7xxx_pci;

static const struct e7xxx_dev_info e7xxx_devs[] = {
	[E7500] = {
		.err_dev = PCI_DEVICE_ID_INTEL_7500_1_ERR,
		.ctl_name = "E7500"},
	[E7501] = {
		.err_dev = PCI_DEVICE_ID_INTEL_7501_1_ERR,
		.ctl_name = "E7501"},
	[E7505] = {
		.err_dev = PCI_DEVICE_ID_INTEL_7505_1_ERR,
		.ctl_name = "E7505"},
	[E7205] = {
		.err_dev = PCI_DEVICE_ID_INTEL_7205_1_ERR,
		.ctl_name = "E7205"},
};

/* FIXME - is this valid for both SECDED and S4ECD4ED? */
static inline int e7xxx_find_channel(u16 syndrome)
{
	debugf3("%s()\n", __func__);

	if ((syndrome & 0xff00) == 0)
		return 0;

	if ((syndrome & 0x00ff) == 0)
		return 1;

	if ((syndrome & 0xf000) == 0 || (syndrome & 0x0f00) == 0)
		return 0;

	return 1;
}

static unsigned long ctl_page_to_phys(struct mem_ctl_info *mci,
				unsigned long page)
{
	u32 remap;
	struct e7xxx_pvt *pvt = (struct e7xxx_pvt *)mci->pvt_info;

	debugf3("%s()\n", __func__);

	if ((page < pvt->tolm) ||
		((page >= 0x100000) && (page < pvt->remapbase)))
		return page;

	remap = (page - pvt->tolm) + pvt->remapbase;

	if (remap < pvt->remaplimit)
		return remap;

	e7xxx_printk(KERN_ERR, "Invalid page %lx - out of range\n", page);
	return pvt->tolm - 1;
}

static void process_ce(struct mem_ctl_info *mci, struct e7xxx_error_info *info)
{
	u32 error_1b, page;
	u16 syndrome;
	int row;
	int channel;

	debugf3("%s()\n", __func__);
	/* read the error address */
	error_1b = info->dram_celog_add;
	/* FIXME - should use PAGE_SHIFT */
	page = error_1b >> 6;	/* convert the address to 4k page */
	/* read the syndrome */
	syndrome = info->dram_celog_syndrome;
	/* FIXME - check for -1 */
	row = edac_mc_find_csrow_by_page(mci, page);
	/* convert syndrome to channel */
	channel = e7xxx_find_channel(syndrome);
	edac_mc_handle_ce(mci, page, 0, syndrome, row, channel, "e7xxx CE");
}

static void process_ce_no_info(struct mem_ctl_info *mci)
{
	debugf3("%s()\n", __func__);
	edac_mc_handle_ce_no_info(mci, "e7xxx CE log register overflow");
}

static void process_ue(struct mem_ctl_info *mci, struct e7xxx_error_info *info)
{
	u32 error_2b, block_page;
	int row;

	debugf3("%s()\n", __func__);
	/* read the error address */
	error_2b = info->dram_uelog_add;
	/* FIXME - should use PAGE_SHIFT */
	block_page = error_2b >> 6;	/* convert to 4k address */
	row = edac_mc_find_csrow_by_page(mci, block_page);
	edac_mc_handle_ue(mci, block_page, 0, row, "e7xxx UE");
}

static void process_ue_no_info(struct mem_ctl_info *mci)
{
	debugf3("%s()\n", __func__);
	edac_mc_handle_ue_no_info(mci, "e7xxx UE log register overflow");
}

static void e7xxx_get_error_info(struct mem_ctl_info *mci,
				 struct e7xxx_error_info *info)
{
	struct e7xxx_pvt *pvt;

	pvt = (struct e7xxx_pvt *)mci->pvt_info;
	pci_read_config_byte(pvt->bridge_ck, E7XXX_DRAM_FERR, &info->dram_ferr);
	pci_read_config_byte(pvt->bridge_ck, E7XXX_DRAM_NERR, &info->dram_nerr);

	if ((info->dram_ferr & 1) || (info->dram_nerr & 1)) {
		pci_read_config_dword(pvt->bridge_ck, E7XXX_DRAM_CELOG_ADD,
				&info->dram_celog_add);
		pci_read_config_word(pvt->bridge_ck,
				E7XXX_DRAM_CELOG_SYNDROME,
				&info->dram_celog_syndrome);
	}

	if ((info->dram_ferr & 2) || (info->dram_nerr & 2))
		pci_read_config_dword(pvt->bridge_ck, E7XXX_DRAM_UELOG_ADD,
				&info->dram_uelog_add);

	if (info->dram_ferr & 3)
		pci_write_bits8(pvt->bridge_ck, E7XXX_DRAM_FERR, 0x03, 0x03);

	if (info->dram_nerr & 3)
		pci_write_bits8(pvt->bridge_ck, E7XXX_DRAM_NERR, 0x03, 0x03);
}

static int e7xxx_process_error_info(struct mem_ctl_info *mci,
				struct e7xxx_error_info *info,
				int handle_errors)
{
	int error_found;

	error_found = 0;

	/* decode and report errors */
	if (info->dram_ferr & 1) {	/* check first error correctable */
		error_found = 1;

		if (handle_errors)
			process_ce(mci, info);
	}

	if (info->dram_ferr & 2) {	/* check first error uncorrectable */
		error_found = 1;

		if (handle_errors)
			process_ue(mci, info);
	}

	if (info->dram_nerr & 1) {	/* check next error correctable */
		error_found = 1;

		if (handle_errors) {
			if (info->dram_ferr & 1)
				process_ce_no_info(mci);
			else
				process_ce(mci, info);
		}
	}

	if (info->dram_nerr & 2) {	/* check next error uncorrectable */
		error_found = 1;

		if (handle_errors) {
			if (info->dram_ferr & 2)
				process_ue_no_info(mci);
			else
				process_ue(mci, info);
		}
	}

	return error_found;
}

static void e7xxx_check(struct mem_ctl_info *mci)
{
	struct e7xxx_error_info info;

	debugf3("%s()\n", __func__);
	e7xxx_get_error_info(mci, &info);
	e7xxx_process_error_info(mci, &info, 1);
}

/* Return 1 if dual channel mode is active.  Else return 0. */
static inline int dual_channel_active(u32 drc, int dev_idx)
{
	return (dev_idx == E7501) ? ((drc >> 22) & 0x1) : 1;
}

/* Return DRB granularity (0=32mb, 1=64mb). */
static inline int drb_granularity(u32 drc, int dev_idx)
{
	/* only e7501 can be single channel */
	return (dev_idx == E7501) ? ((drc >> 18) & 0x3) : 1;
}

static void e7xxx_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
			int dev_idx, u32 drc)
{
	unsigned long last_cumul_size;
	int index;
	u8 value;
	u32 dra, cumul_size;
	int drc_chan, drc_drbg, drc_ddim, mem_dev;
	struct csrow_info *csrow;

	pci_read_config_dword(pdev, E7XXX_DRA, &dra);
	drc_chan = dual_channel_active(drc, dev_idx);
	drc_drbg = drb_granularity(drc, dev_idx);
	drc_ddim = (drc >> 20) & 0x3;
	last_cumul_size = 0;

	/* The dram row boundary (DRB) reg values are boundary address
	 * for each DRAM row with a granularity of 32 or 64MB (single/dual
	 * channel operation).  DRB regs are cumulative; therefore DRB7 will
	 * contain the total memory contained in all eight rows.
	 */
	for (index = 0; index < mci->nr_csrows; index++) {
		/* mem_dev 0=x8, 1=x4 */
		mem_dev = (dra >> (index * 4 + 3)) & 0x1;
		csrow = &mci->csrows[index];

		pci_read_config_byte(pdev, E7XXX_DRB + index, &value);
		/* convert a 64 or 32 MiB DRB to a page size. */
		cumul_size = value << (25 + drc_drbg - PAGE_SHIFT);
		debugf3("%s(): (%d) cumul_size 0x%x\n", __func__, index,
			cumul_size);
		if (cumul_size == last_cumul_size)
			continue;	/* not populated */

		csrow->first_page = last_cumul_size;
		csrow->last_page = cumul_size - 1;
		csrow->nr_pages = cumul_size - last_cumul_size;
		last_cumul_size = cumul_size;
		csrow->grain = 1 << 12;	/* 4KiB - resolution of CELOG */
		csrow->mtype = MEM_RDDR;	/* only one type supported */
		csrow->dtype = mem_dev ? DEV_X4 : DEV_X8;

		/*
		 * if single channel or x8 devices then SECDED
		 * if dual channel and x4 then S4ECD4ED
		 */
		if (drc_ddim) {
			if (drc_chan && mem_dev) {
				csrow->edac_mode = EDAC_S4ECD4ED;
				mci->edac_cap |= EDAC_FLAG_S4ECD4ED;
			} else {
				csrow->edac_mode = EDAC_SECDED;
				mci->edac_cap |= EDAC_FLAG_SECDED;
			}
		} else
			csrow->edac_mode = EDAC_NONE;
	}
}

static int e7xxx_probe1(struct pci_dev *pdev, int dev_idx)
{
	u16 pci_data;
	struct mem_ctl_info *mci = NULL;
	struct e7xxx_pvt *pvt = NULL;
	u32 drc;
	int drc_chan;
	struct e7xxx_error_info discard;

	debugf0("%s(): mci\n", __func__);

	/* make sure error reporting method is sane */
	switch (edac_op_state) {
	case EDAC_OPSTATE_POLL:
	case EDAC_OPSTATE_NMI:
		break;
	default:
		edac_op_state = EDAC_OPSTATE_POLL;
		break;
	}

	pci_read_config_dword(pdev, E7XXX_DRC, &drc);

	drc_chan = dual_channel_active(drc, dev_idx);
	mci = edac_mc_alloc(sizeof(*pvt), E7XXX_NR_CSROWS, drc_chan + 1, 0);

	if (mci == NULL)
		return -ENOMEM;

	debugf3("%s(): init mci\n", __func__);
	mci->mtype_cap = MEM_FLAG_RDDR;
	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED |
		EDAC_FLAG_S4ECD4ED;
	/* FIXME - what if different memory types are in different csrows? */
	mci->mod_name = EDAC_MOD_STR;
	mci->mod_ver = E7XXX_REVISION;
	mci->dev = &pdev->dev;
	debugf3("%s(): init pvt\n", __func__);
	pvt = (struct e7xxx_pvt *)mci->pvt_info;
	pvt->dev_info = &e7xxx_devs[dev_idx];
	pvt->bridge_ck = pci_get_device(PCI_VENDOR_ID_INTEL,
					pvt->dev_info->err_dev, pvt->bridge_ck);

	if (!pvt->bridge_ck) {
		e7xxx_printk(KERN_ERR, "error reporting device not found:"
			"vendor %x device 0x%x (broken BIOS?)\n",
			PCI_VENDOR_ID_INTEL, e7xxx_devs[dev_idx].err_dev);
		goto fail0;
	}

	debugf3("%s(): more mci init\n", __func__);
	mci->ctl_name = pvt->dev_info->ctl_name;
	mci->dev_name = pci_name(pdev);
	mci->edac_check = e7xxx_check;
	mci->ctl_page_to_phys = ctl_page_to_phys;
	e7xxx_init_csrows(mci, pdev, dev_idx, drc);
	mci->edac_cap |= EDAC_FLAG_NONE;
	debugf3("%s(): tolm, remapbase, remaplimit\n", __func__);
	/* load the top of low memory, remap base, and remap limit vars */
	pci_read_config_word(pdev, E7XXX_TOLM, &pci_data);
	pvt->tolm = ((u32) pci_data) << 4;
	pci_read_config_word(pdev, E7XXX_REMAPBASE, &pci_data);
	pvt->remapbase = ((u32) pci_data) << 14;
	pci_read_config_word(pdev, E7XXX_REMAPLIMIT, &pci_data);
	pvt->remaplimit = ((u32) pci_data) << 14;
	e7xxx_printk(KERN_INFO,
		"tolm = %x, remapbase = %x, remaplimit = %x\n", pvt->tolm,
		pvt->remapbase, pvt->remaplimit);

	/* clear any pending errors, or initial state bits */
	e7xxx_get_error_info(mci, &discard);

	/* Here we assume that we will never see multiple instances of this
	 * type of memory controller.  The ID is therefore hardcoded to 0.
	 */
	if (edac_mc_add_mc(mci)) {
		debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
		goto fail1;
	}

	/* allocating generic PCI control info */
	e7xxx_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
	if (!e7xxx_pci) {
		printk(KERN_WARNING
			"%s(): Unable to create PCI control\n",
			__func__);
		printk(KERN_WARNING
			"%s(): PCI error report via EDAC not setup\n",
			__func__);
	}

	/* get this far and it's successful */
	debugf3("%s(): success\n", __func__);
	return 0;

fail1:
	pci_dev_put(pvt->bridge_ck);

fail0:
	edac_mc_free(mci);

	return -ENODEV;
}

/* returns count (>= 0), or negative on error */
static int __devinit e7xxx_init_one(struct pci_dev *pdev,
				const struct pci_device_id *ent)
{
	debugf0("%s()\n", __func__);

	/* wake up and enable device */
	return pci_enable_device(pdev) ?
		-EIO : e7xxx_probe1(pdev, ent->driver_data);
}

static void __devexit e7xxx_remove_one(struct pci_dev *pdev)
{
	struct mem_ctl_info *mci;
	struct e7xxx_pvt *pvt;

	debugf0("%s()\n", __func__);

	if (e7xxx_pci)
		edac_pci_release_generic_ctl(e7xxx_pci);

	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
		return;

	pvt = (struct e7xxx_pvt *)mci->pvt_info;
	pci_dev_put(pvt->bridge_ck);
	edac_mc_free(mci);
}

static const struct pci_device_id e7xxx_pci_tbl[] __devinitdata = {
	{
	 PCI_VEND_DEV(INTEL, 7205_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	 E7205},
	{
	 PCI_VEND_DEV(INTEL, 7500_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	 E7500},
	{
	 PCI_VEND_DEV(INTEL, 7501_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	 E7501},
	{
	 PCI_VEND_DEV(INTEL, 7505_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	 E7505},
	{
	 0,
	 }			/* 0 terminated list. */
};

MODULE_DEVICE_TABLE(pci, e7xxx_pci_tbl);

static struct pci_driver e7xxx_driver = {
	.name = EDAC_MOD_STR,
	.probe = e7xxx_init_one,
	.remove = __devexit_p(e7xxx_remove_one),
	.id_table = e7xxx_pci_tbl,
};

static int __init e7xxx_init(void)
{
	return pci_register_driver(&e7xxx_driver);
}

static void __exit e7xxx_exit(void)
{
	pci_unregister_driver(&e7xxx_driver);
}

module_init(e7xxx_init);
module_exit(e7xxx_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Linux Networx (http://lnxi.com) Thayne Harbaugh et al\n"
		"Based on.work by Dan Hollis et al");
MODULE_DESCRIPTION("MC support for Intel e7xxx memory controllers");
module_param(edac_op_state, int, 0444);
MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");