xref: /openbmc/linux/drivers/edac/i82975x_edac.c (revision 82e6fdd6)
1 /*
2  * Intel 82975X Memory Controller kernel module
3  * (C) 2007 aCarLab (India) Pvt. Ltd. (http://acarlab.com)
4  * (C) 2007 jetzbroadband (http://jetzbroadband.com)
5  * This file may be distributed under the terms of the
6  * GNU General Public License.
7  *
8  * Written by Arvind R.
9  *   Copied from i82875p_edac.c source:
10  */
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/pci.h>
15 #include <linux/pci_ids.h>
16 #include <linux/edac.h>
17 #include "edac_module.h"
18 
19 #define EDAC_MOD_STR		"i82975x_edac"
20 
21 #define i82975x_printk(level, fmt, arg...) \
22 	edac_printk(level, "i82975x", fmt, ##arg)
23 
24 #define i82975x_mc_printk(mci, level, fmt, arg...) \
25 	edac_mc_chipset_printk(mci, level, "i82975x", fmt, ##arg)
26 
27 #ifndef PCI_DEVICE_ID_INTEL_82975_0
28 #define PCI_DEVICE_ID_INTEL_82975_0	0x277c
29 #endif				/* PCI_DEVICE_ID_INTEL_82975_0 */
30 
31 #define I82975X_NR_DIMMS		8
32 #define I82975X_NR_CSROWS(nr_chans)	(I82975X_NR_DIMMS / (nr_chans))
33 
34 /* Intel 82975X register addresses - device 0 function 0 - DRAM Controller */
35 #define I82975X_EAP		0x58	/* Dram Error Address Pointer (32b)
36 					 *
37 					 * 31:7  128 byte cache-line address
38 					 * 6:1   reserved
39 					 * 0     0: CH0; 1: CH1
40 					 */
41 
42 #define I82975X_DERRSYN		0x5c	/* Dram Error SYNdrome (8b)
43 					 *
44 					 *  7:0  DRAM ECC Syndrome
45 					 */
46 
47 #define I82975X_DES		0x5d	/* Dram ERRor DeSTination (8b)
48 					 * 0h:    Processor Memory Reads
49 					 * 1h:7h  reserved
50 					 * More - See Page 65 of Intel DocSheet.
51 					 */
52 
53 #define I82975X_ERRSTS		0xc8	/* Error Status Register (16b)
54 					 *
55 					 * 15:12 reserved
56 					 * 11    Thermal Sensor Event
57 					 * 10    reserved
58 					 *  9    non-DRAM lock error (ndlock)
59 					 *  8    Refresh Timeout
60 					 *  7:2  reserved
61 					 *  1    ECC UE (multibit DRAM error)
62 					 *  0    ECC CE (singlebit DRAM error)
63 					 */
64 
65 /* Error Reporting is supported by 3 mechanisms:
66   1. DMI SERR generation  ( ERRCMD )
67   2. SMI DMI  generation  ( SMICMD )
68   3. SCI DMI  generation  ( SCICMD )
69 NOTE: Only ONE of the three must be enabled
70 */
71 #define I82975X_ERRCMD		0xca	/* Error Command (16b)
72 					 *
73 					 * 15:12 reserved
74 					 * 11    Thermal Sensor Event
75 					 * 10    reserved
76 					 *  9    non-DRAM lock error (ndlock)
77 					 *  8    Refresh Timeout
78 					 *  7:2  reserved
79 					 *  1    ECC UE (multibit DRAM error)
80 					 *  0    ECC CE (singlebit DRAM error)
81 					 */
82 
83 #define I82975X_SMICMD		0xcc	/* Error Command (16b)
84 					 *
85 					 * 15:2  reserved
86 					 *  1    ECC UE (multibit DRAM error)
87 					 *  0    ECC CE (singlebit DRAM error)
88 					 */
89 
90 #define I82975X_SCICMD		0xce	/* Error Command (16b)
91 					 *
92 					 * 15:2  reserved
93 					 *  1    ECC UE (multibit DRAM error)
94 					 *  0    ECC CE (singlebit DRAM error)
95 					 */
96 
97 #define I82975X_XEAP	0xfc	/* Extended Dram Error Address Pointer (8b)
98 					 *
99 					 * 7:1   reserved
100 					 * 0     Bit32 of the Dram Error Address
101 					 */
102 
103 #define I82975X_MCHBAR		0x44	/*
104 					 *
105 					 * 31:14 Base Addr of 16K memory-mapped
106 					 *	configuration space
107 					 * 13:1  reserverd
108 					 *  0    mem-mapped config space enable
109 					 */
110 
111 /* NOTE: Following addresses have to indexed using MCHBAR offset (44h, 32b) */
112 /* Intel 82975x memory mapped register space */
113 
114 #define I82975X_DRB_SHIFT 25	/* fixed 32MiB grain */
115 
116 #define I82975X_DRB		0x100	/* DRAM Row Boundary (8b x 8)
117 					 *
118 					 * 7   set to 1 in highest DRB of
119 					 *	channel if 4GB in ch.
120 					 * 6:2 upper boundary of rank in
121 					 *	32MB grains
122 					 * 1:0 set to 0
123 					 */
124 #define I82975X_DRB_CH0R0		0x100
125 #define I82975X_DRB_CH0R1		0x101
126 #define I82975X_DRB_CH0R2		0x102
127 #define I82975X_DRB_CH0R3		0x103
128 #define I82975X_DRB_CH1R0		0x180
129 #define I82975X_DRB_CH1R1		0x181
130 #define I82975X_DRB_CH1R2		0x182
131 #define I82975X_DRB_CH1R3		0x183
132 
133 
134 #define I82975X_DRA		0x108	/* DRAM Row Attribute (4b x 8)
135 					 *  defines the PAGE SIZE to be used
136 					 *	for the rank
137 					 *  7    reserved
138 					 *  6:4  row attr of odd rank, i.e. 1
139 					 *  3    reserved
140 					 *  2:0  row attr of even rank, i.e. 0
141 					 *
142 					 * 000 = unpopulated
143 					 * 001 = reserved
144 					 * 010 = 4KiB
145 					 * 011 = 8KiB
146 					 * 100 = 16KiB
147 					 * others = reserved
148 					 */
149 #define I82975X_DRA_CH0R01		0x108
150 #define I82975X_DRA_CH0R23		0x109
151 #define I82975X_DRA_CH1R01		0x188
152 #define I82975X_DRA_CH1R23		0x189
153 
154 
155 #define I82975X_BNKARC	0x10e /* Type of device in each rank - Bank Arch (16b)
156 					 *
157 					 * 15:8  reserved
158 					 * 7:6  Rank 3 architecture
159 					 * 5:4  Rank 2 architecture
160 					 * 3:2  Rank 1 architecture
161 					 * 1:0  Rank 0 architecture
162 					 *
163 					 * 00 => 4 banks
164 					 * 01 => 8 banks
165 					 */
166 #define I82975X_C0BNKARC	0x10e
167 #define I82975X_C1BNKARC	0x18e
168 
169 
170 
171 #define I82975X_DRC		0x120 /* DRAM Controller Mode0 (32b)
172 					 *
173 					 * 31:30 reserved
174 					 * 29    init complete
175 					 * 28:11 reserved, according to Intel
176 					 *    22:21 number of channels
177 					 *		00=1 01=2 in 82875
178 					 *		seems to be ECC mode
179 					 *		bits in 82975 in Asus
180 					 *		P5W
181 					 *	 19:18 Data Integ Mode
182 					 *		00=none 01=ECC in 82875
183 					 * 10:8  refresh mode
184 					 *  7    reserved
185 					 *  6:4  mode select
186 					 *  3:2  reserved
187 					 *  1:0  DRAM type 10=Second Revision
188 					 *		DDR2 SDRAM
189 					 *         00, 01, 11 reserved
190 					 */
191 #define I82975X_DRC_CH0M0		0x120
192 #define I82975X_DRC_CH1M0		0x1A0
193 
194 
195 #define I82975X_DRC_M1	0x124 /* DRAM Controller Mode1 (32b)
196 					 * 31	0=Standard Address Map
197 					 *	1=Enhanced Address Map
198 					 * 30:0	reserved
199 					 */
200 
201 #define I82975X_DRC_CH0M1		0x124
202 #define I82975X_DRC_CH1M1		0x1A4
203 
204 enum i82975x_chips {
205 	I82975X = 0,
206 };
207 
208 struct i82975x_pvt {
209 	void __iomem *mch_window;
210 };
211 
212 struct i82975x_dev_info {
213 	const char *ctl_name;
214 };
215 
216 struct i82975x_error_info {
217 	u16 errsts;
218 	u32 eap;
219 	u8 des;
220 	u8 derrsyn;
221 	u16 errsts2;
222 	u8 chan;		/* the channel is bit 0 of EAP */
223 	u8 xeap;		/* extended eap bit */
224 };
225 
226 static const struct i82975x_dev_info i82975x_devs[] = {
227 	[I82975X] = {
228 		.ctl_name = "i82975x"
229 	},
230 };
231 
232 static struct pci_dev *mci_pdev;	/* init dev: in case that AGP code has
233 					 * already registered driver
234 					 */
235 
236 static int i82975x_registered = 1;
237 
238 static void i82975x_get_error_info(struct mem_ctl_info *mci,
239 		struct i82975x_error_info *info)
240 {
241 	struct pci_dev *pdev;
242 
243 	pdev = to_pci_dev(mci->pdev);
244 
245 	/*
246 	 * This is a mess because there is no atomic way to read all the
247 	 * registers at once and the registers can transition from CE being
248 	 * overwritten by UE.
249 	 */
250 	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts);
251 	pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
252 	pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
253 	pci_read_config_byte(pdev, I82975X_DES, &info->des);
254 	pci_read_config_byte(pdev, I82975X_DERRSYN, &info->derrsyn);
255 	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts2);
256 
257 	pci_write_bits16(pdev, I82975X_ERRSTS, 0x0003, 0x0003);
258 
259 	/*
260 	 * If the error is the same then we can for both reads then
261 	 * the first set of reads is valid.  If there is a change then
262 	 * there is a CE no info and the second set of reads is valid
263 	 * and should be UE info.
264 	 */
265 	if (!(info->errsts2 & 0x0003))
266 		return;
267 
268 	if ((info->errsts ^ info->errsts2) & 0x0003) {
269 		pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
270 		pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
271 		pci_read_config_byte(pdev, I82975X_DES, &info->des);
272 		pci_read_config_byte(pdev, I82975X_DERRSYN,
273 				&info->derrsyn);
274 	}
275 }
276 
277 static int i82975x_process_error_info(struct mem_ctl_info *mci,
278 		struct i82975x_error_info *info, int handle_errors)
279 {
280 	int row, chan;
281 	unsigned long offst, page;
282 
283 	if (!(info->errsts2 & 0x0003))
284 		return 0;
285 
286 	if (!handle_errors)
287 		return 1;
288 
289 	if ((info->errsts ^ info->errsts2) & 0x0003) {
290 		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1, 0, 0, 0,
291 				     -1, -1, -1, "UE overwrote CE", "");
292 		info->errsts = info->errsts2;
293 	}
294 
295 	page = (unsigned long) info->eap;
296 	page >>= 1;
297 	if (info->xeap & 1)
298 		page |= 0x80000000;
299 	page >>= (PAGE_SHIFT - 1);
300 	row = edac_mc_find_csrow_by_page(mci, page);
301 
302 	if (row == -1)	{
303 		i82975x_mc_printk(mci, KERN_ERR, "error processing EAP:\n"
304 			"\tXEAP=%u\n"
305 			"\t EAP=0x%08x\n"
306 			"\tPAGE=0x%08x\n",
307 			(info->xeap & 1) ? 1 : 0, info->eap, (unsigned int) page);
308 		return 0;
309 	}
310 	chan = (mci->csrows[row]->nr_channels == 1) ? 0 : info->eap & 1;
311 	offst = info->eap
312 			& ((1 << PAGE_SHIFT) -
313 			   (1 << mci->csrows[row]->channels[chan]->dimm->grain));
314 
315 	if (info->errsts & 0x0002)
316 		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
317 				     page, offst, 0,
318 				     row, -1, -1,
319 				     "i82975x UE", "");
320 	else
321 		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
322 				     page, offst, info->derrsyn,
323 				     row, chan ? chan : 0, -1,
324 				     "i82975x CE", "");
325 
326 	return 1;
327 }
328 
329 static void i82975x_check(struct mem_ctl_info *mci)
330 {
331 	struct i82975x_error_info info;
332 
333 	edac_dbg(1, "MC%d\n", mci->mc_idx);
334 	i82975x_get_error_info(mci, &info);
335 	i82975x_process_error_info(mci, &info, 1);
336 }
337 
338 /* Return 1 if dual channel mode is active.  Else return 0. */
339 static int dual_channel_active(void __iomem *mch_window)
340 {
341 	/*
342 	 * We treat interleaved-symmetric configuration as dual-channel - EAP's
343 	 * bit-0 giving the channel of the error location.
344 	 *
345 	 * All other configurations are treated as single channel - the EAP's
346 	 * bit-0 will resolve ok in symmetric area of mixed
347 	 * (symmetric/asymmetric) configurations
348 	 */
349 	u8	drb[4][2];
350 	int	row;
351 	int    dualch;
352 
353 	for (dualch = 1, row = 0; dualch && (row < 4); row++) {
354 		drb[row][0] = readb(mch_window + I82975X_DRB + row);
355 		drb[row][1] = readb(mch_window + I82975X_DRB + row + 0x80);
356 		dualch = dualch && (drb[row][0] == drb[row][1]);
357 	}
358 	return dualch;
359 }
360 
361 static enum dev_type i82975x_dram_type(void __iomem *mch_window, int rank)
362 {
363 	/*
364 	 * ECC is possible on i92975x ONLY with DEV_X8
365 	 */
366 	return DEV_X8;
367 }
368 
369 static void i82975x_init_csrows(struct mem_ctl_info *mci,
370 		struct pci_dev *pdev, void __iomem *mch_window)
371 {
372 	struct csrow_info *csrow;
373 	unsigned long last_cumul_size;
374 	u8 value;
375 	u32 cumul_size, nr_pages;
376 	int index, chan;
377 	struct dimm_info *dimm;
378 	enum dev_type dtype;
379 
380 	last_cumul_size = 0;
381 
382 	/*
383 	 * 82875 comment:
384 	 * The dram row boundary (DRB) reg values are boundary address
385 	 * for each DRAM row with a granularity of 32 or 64MB (single/dual
386 	 * channel operation).  DRB regs are cumulative; therefore DRB7 will
387 	 * contain the total memory contained in all rows.
388 	 *
389 	 */
390 
391 	for (index = 0; index < mci->nr_csrows; index++) {
392 		csrow = mci->csrows[index];
393 
394 		value = readb(mch_window + I82975X_DRB + index +
395 					((index >= 4) ? 0x80 : 0));
396 		cumul_size = value;
397 		cumul_size <<= (I82975X_DRB_SHIFT - PAGE_SHIFT);
398 		/*
399 		 * Adjust cumul_size w.r.t number of channels
400 		 *
401 		 */
402 		if (csrow->nr_channels > 1)
403 			cumul_size <<= 1;
404 		edac_dbg(3, "(%d) cumul_size 0x%x\n", index, cumul_size);
405 
406 		nr_pages = cumul_size - last_cumul_size;
407 		if (!nr_pages)
408 			continue;
409 
410 		/*
411 		 * Initialise dram labels
412 		 * index values:
413 		 *   [0-7] for single-channel; i.e. csrow->nr_channels = 1
414 		 *   [0-3] for dual-channel; i.e. csrow->nr_channels = 2
415 		 */
416 		dtype = i82975x_dram_type(mch_window, index);
417 		for (chan = 0; chan < csrow->nr_channels; chan++) {
418 			dimm = mci->csrows[index]->channels[chan]->dimm;
419 
420 			dimm->nr_pages = nr_pages / csrow->nr_channels;
421 
422 			snprintf(csrow->channels[chan]->dimm->label, EDAC_MC_LABEL_LEN, "DIMM %c%d",
423 				 (chan == 0) ? 'A' : 'B',
424 				 index);
425 			dimm->grain = 1 << 7;	/* 128Byte cache-line resolution */
426 			dimm->dtype = i82975x_dram_type(mch_window, index);
427 			dimm->mtype = MEM_DDR2; /* I82975x supports only DDR2 */
428 			dimm->edac_mode = EDAC_SECDED; /* only supported */
429 		}
430 
431 		csrow->first_page = last_cumul_size;
432 		csrow->last_page = cumul_size - 1;
433 		last_cumul_size = cumul_size;
434 	}
435 }
436 
437 /* #define  i82975x_DEBUG_IOMEM */
438 
439 #ifdef i82975x_DEBUG_IOMEM
440 static void i82975x_print_dram_timings(void __iomem *mch_window)
441 {
442 	/*
443 	 * The register meanings are from Intel specs;
444 	 * (shows 13-5-5-5 for 800-DDR2)
445 	 * Asus P5W Bios reports 15-5-4-4
446 	 * What's your religion?
447 	 */
448 	static const int caslats[4] = { 5, 4, 3, 6 };
449 	u32	dtreg[2];
450 
451 	dtreg[0] = readl(mch_window + 0x114);
452 	dtreg[1] = readl(mch_window + 0x194);
453 	i82975x_printk(KERN_INFO, "DRAM Timings :     Ch0    Ch1\n"
454 		"                RAS Active Min = %d     %d\n"
455 		"                CAS latency    =  %d      %d\n"
456 		"                RAS to CAS     =  %d      %d\n"
457 		"                RAS precharge  =  %d      %d\n",
458 		(dtreg[0] >> 19 ) & 0x0f,
459 			(dtreg[1] >> 19) & 0x0f,
460 		caslats[(dtreg[0] >> 8) & 0x03],
461 			caslats[(dtreg[1] >> 8) & 0x03],
462 		((dtreg[0] >> 4) & 0x07) + 2,
463 			((dtreg[1] >> 4) & 0x07) + 2,
464 		(dtreg[0] & 0x07) + 2,
465 			(dtreg[1] & 0x07) + 2
466 	);
467 
468 }
469 #endif
470 
471 static int i82975x_probe1(struct pci_dev *pdev, int dev_idx)
472 {
473 	int rc = -ENODEV;
474 	struct mem_ctl_info *mci;
475 	struct edac_mc_layer layers[2];
476 	struct i82975x_pvt *pvt;
477 	void __iomem *mch_window;
478 	u32 mchbar;
479 	u32 drc[2];
480 	struct i82975x_error_info discard;
481 	int	chans;
482 #ifdef i82975x_DEBUG_IOMEM
483 	u8 c0drb[4];
484 	u8 c1drb[4];
485 #endif
486 
487 	edac_dbg(0, "\n");
488 
489 	pci_read_config_dword(pdev, I82975X_MCHBAR, &mchbar);
490 	if (!(mchbar & 1)) {
491 		edac_dbg(3, "failed, MCHBAR disabled!\n");
492 		goto fail0;
493 	}
494 	mchbar &= 0xffffc000;	/* bits 31:14 used for 16K window */
495 	mch_window = ioremap_nocache(mchbar, 0x1000);
496 	if (!mch_window) {
497 		edac_dbg(3, "error ioremapping MCHBAR!\n");
498 		goto fail0;
499 	}
500 
501 #ifdef i82975x_DEBUG_IOMEM
502 	i82975x_printk(KERN_INFO, "MCHBAR real = %0x, remapped = %p\n",
503 					mchbar, mch_window);
504 
505 	c0drb[0] = readb(mch_window + I82975X_DRB_CH0R0);
506 	c0drb[1] = readb(mch_window + I82975X_DRB_CH0R1);
507 	c0drb[2] = readb(mch_window + I82975X_DRB_CH0R2);
508 	c0drb[3] = readb(mch_window + I82975X_DRB_CH0R3);
509 	c1drb[0] = readb(mch_window + I82975X_DRB_CH1R0);
510 	c1drb[1] = readb(mch_window + I82975X_DRB_CH1R1);
511 	c1drb[2] = readb(mch_window + I82975X_DRB_CH1R2);
512 	c1drb[3] = readb(mch_window + I82975X_DRB_CH1R3);
513 	i82975x_printk(KERN_INFO, "DRBCH0R0 = 0x%02x\n", c0drb[0]);
514 	i82975x_printk(KERN_INFO, "DRBCH0R1 = 0x%02x\n", c0drb[1]);
515 	i82975x_printk(KERN_INFO, "DRBCH0R2 = 0x%02x\n", c0drb[2]);
516 	i82975x_printk(KERN_INFO, "DRBCH0R3 = 0x%02x\n", c0drb[3]);
517 	i82975x_printk(KERN_INFO, "DRBCH1R0 = 0x%02x\n", c1drb[0]);
518 	i82975x_printk(KERN_INFO, "DRBCH1R1 = 0x%02x\n", c1drb[1]);
519 	i82975x_printk(KERN_INFO, "DRBCH1R2 = 0x%02x\n", c1drb[2]);
520 	i82975x_printk(KERN_INFO, "DRBCH1R3 = 0x%02x\n", c1drb[3]);
521 #endif
522 
523 	drc[0] = readl(mch_window + I82975X_DRC_CH0M0);
524 	drc[1] = readl(mch_window + I82975X_DRC_CH1M0);
525 #ifdef i82975x_DEBUG_IOMEM
526 	i82975x_printk(KERN_INFO, "DRC_CH0 = %0x, %s\n", drc[0],
527 			((drc[0] >> 21) & 3) == 1 ?
528 				"ECC enabled" : "ECC disabled");
529 	i82975x_printk(KERN_INFO, "DRC_CH1 = %0x, %s\n", drc[1],
530 			((drc[1] >> 21) & 3) == 1 ?
531 				"ECC enabled" : "ECC disabled");
532 
533 	i82975x_printk(KERN_INFO, "C0 BNKARC = %0x\n",
534 		readw(mch_window + I82975X_C0BNKARC));
535 	i82975x_printk(KERN_INFO, "C1 BNKARC = %0x\n",
536 		readw(mch_window + I82975X_C1BNKARC));
537 	i82975x_print_dram_timings(mch_window);
538 	goto fail1;
539 #endif
540 	if (!(((drc[0] >> 21) & 3) == 1 || ((drc[1] >> 21) & 3) == 1)) {
541 		i82975x_printk(KERN_INFO, "ECC disabled on both channels.\n");
542 		goto fail1;
543 	}
544 
545 	chans = dual_channel_active(mch_window) + 1;
546 
547 	/* assuming only one controller, index thus is 0 */
548 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
549 	layers[0].size = I82975X_NR_DIMMS;
550 	layers[0].is_virt_csrow = true;
551 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
552 	layers[1].size = I82975X_NR_CSROWS(chans);
553 	layers[1].is_virt_csrow = false;
554 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, sizeof(*pvt));
555 	if (!mci) {
556 		rc = -ENOMEM;
557 		goto fail1;
558 	}
559 
560 	edac_dbg(3, "init mci\n");
561 	mci->pdev = &pdev->dev;
562 	mci->mtype_cap = MEM_FLAG_DDR2;
563 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
564 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
565 	mci->mod_name = EDAC_MOD_STR;
566 	mci->ctl_name = i82975x_devs[dev_idx].ctl_name;
567 	mci->dev_name = pci_name(pdev);
568 	mci->edac_check = i82975x_check;
569 	mci->ctl_page_to_phys = NULL;
570 	edac_dbg(3, "init pvt\n");
571 	pvt = (struct i82975x_pvt *) mci->pvt_info;
572 	pvt->mch_window = mch_window;
573 	i82975x_init_csrows(mci, pdev, mch_window);
574 	mci->scrub_mode = SCRUB_HW_SRC;
575 	i82975x_get_error_info(mci, &discard);  /* clear counters */
576 
577 	/* finalize this instance of memory controller with edac core */
578 	if (edac_mc_add_mc(mci)) {
579 		edac_dbg(3, "failed edac_mc_add_mc()\n");
580 		goto fail2;
581 	}
582 
583 	/* get this far and it's successful */
584 	edac_dbg(3, "success\n");
585 	return 0;
586 
587 fail2:
588 	edac_mc_free(mci);
589 
590 fail1:
591 	iounmap(mch_window);
592 fail0:
593 	return rc;
594 }
595 
596 /* returns count (>= 0), or negative on error */
597 static int i82975x_init_one(struct pci_dev *pdev,
598 			    const struct pci_device_id *ent)
599 {
600 	int rc;
601 
602 	edac_dbg(0, "\n");
603 
604 	if (pci_enable_device(pdev) < 0)
605 		return -EIO;
606 
607 	rc = i82975x_probe1(pdev, ent->driver_data);
608 
609 	if (mci_pdev == NULL)
610 		mci_pdev = pci_dev_get(pdev);
611 
612 	return rc;
613 }
614 
615 static void i82975x_remove_one(struct pci_dev *pdev)
616 {
617 	struct mem_ctl_info *mci;
618 	struct i82975x_pvt *pvt;
619 
620 	edac_dbg(0, "\n");
621 
622 	mci = edac_mc_del_mc(&pdev->dev);
623 	if (mci  == NULL)
624 		return;
625 
626 	pvt = mci->pvt_info;
627 	if (pvt->mch_window)
628 		iounmap( pvt->mch_window );
629 
630 	edac_mc_free(mci);
631 }
632 
633 static const struct pci_device_id i82975x_pci_tbl[] = {
634 	{
635 		PCI_VEND_DEV(INTEL, 82975_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
636 		I82975X
637 	},
638 	{
639 		0,
640 	}	/* 0 terminated list. */
641 };
642 
643 MODULE_DEVICE_TABLE(pci, i82975x_pci_tbl);
644 
645 static struct pci_driver i82975x_driver = {
646 	.name = EDAC_MOD_STR,
647 	.probe = i82975x_init_one,
648 	.remove = i82975x_remove_one,
649 	.id_table = i82975x_pci_tbl,
650 };
651 
652 static int __init i82975x_init(void)
653 {
654 	int pci_rc;
655 
656 	edac_dbg(3, "\n");
657 
658        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
659        opstate_init();
660 
661 	pci_rc = pci_register_driver(&i82975x_driver);
662 	if (pci_rc < 0)
663 		goto fail0;
664 
665 	if (mci_pdev == NULL) {
666 		mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
667 				PCI_DEVICE_ID_INTEL_82975_0, NULL);
668 
669 		if (!mci_pdev) {
670 			edac_dbg(0, "i82975x pci_get_device fail\n");
671 			pci_rc = -ENODEV;
672 			goto fail1;
673 		}
674 
675 		pci_rc = i82975x_init_one(mci_pdev, i82975x_pci_tbl);
676 
677 		if (pci_rc < 0) {
678 			edac_dbg(0, "i82975x init fail\n");
679 			pci_rc = -ENODEV;
680 			goto fail1;
681 		}
682 	}
683 
684 	return 0;
685 
686 fail1:
687 	pci_unregister_driver(&i82975x_driver);
688 
689 fail0:
690 	pci_dev_put(mci_pdev);
691 	return pci_rc;
692 }
693 
694 static void __exit i82975x_exit(void)
695 {
696 	edac_dbg(3, "\n");
697 
698 	pci_unregister_driver(&i82975x_driver);
699 
700 	if (!i82975x_registered) {
701 		i82975x_remove_one(mci_pdev);
702 		pci_dev_put(mci_pdev);
703 	}
704 }
705 
706 module_init(i82975x_init);
707 module_exit(i82975x_exit);
708 
709 MODULE_LICENSE("GPL");
710 MODULE_AUTHOR("Arvind R. <arvino55@gmail.com>");
711 MODULE_DESCRIPTION("MC support for Intel 82975 memory hub controllers");
712 
713 module_param(edac_op_state, int, 0444);
714 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
715