xref: /openbmc/linux/drivers/edac/ppc4xx_edac.c (revision b96fc2f3)
1 /*
2  * Copyright (c) 2008 Nuovation System Designs, LLC
3  *   Grant Erickson <gerickson@nuovations.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation; version 2 of the
8  * License.
9  *
10  */
11 
12 #include <linux/edac.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/kernel.h>
16 #include <linux/mm.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/of_platform.h>
20 #include <linux/types.h>
21 
22 #include <asm/dcr.h>
23 
24 #include "edac_core.h"
25 #include "ppc4xx_edac.h"
26 
27 /*
28  * This file implements a driver for monitoring and handling events
29  * associated with the IMB DDR2 ECC controller found in the AMCC/IBM
30  * 405EX[r], 440SP, 440SPe, 460EX, 460GT and 460SX.
31  *
32  * As realized in the 405EX[r], this controller features:
33  *
34  *   - Support for registered- and non-registered DDR1 and DDR2 memory.
35  *   - 32-bit or 16-bit memory interface with optional ECC.
36  *
37  *     o ECC support includes:
38  *
39  *       - 4-bit SEC/DED
40  *       - Aligned-nibble error detect
41  *       - Bypass mode
42  *
43  *   - Two (2) memory banks/ranks.
44  *   - Up to 1 GiB per bank/rank in 32-bit mode and up to 512 MiB per
45  *     bank/rank in 16-bit mode.
46  *
47  * As realized in the 440SP and 440SPe, this controller changes/adds:
48  *
49  *   - 64-bit or 32-bit memory interface with optional ECC.
50  *
51  *     o ECC support includes:
52  *
53  *       - 8-bit SEC/DED
54  *       - Aligned-nibble error detect
55  *       - Bypass mode
56  *
57  *   - Up to 4 GiB per bank/rank in 64-bit mode and up to 2 GiB
58  *     per bank/rank in 32-bit mode.
59  *
60  * As realized in the 460EX and 460GT, this controller changes/adds:
61  *
62  *   - 64-bit or 32-bit memory interface with optional ECC.
63  *
64  *     o ECC support includes:
65  *
66  *       - 8-bit SEC/DED
67  *       - Aligned-nibble error detect
68  *       - Bypass mode
69  *
70  *   - Four (4) memory banks/ranks.
71  *   - Up to 16 GiB per bank/rank in 64-bit mode and up to 8 GiB
72  *     per bank/rank in 32-bit mode.
73  *
74  * At present, this driver has ONLY been tested against the controller
75  * realization in the 405EX[r] on the AMCC Kilauea and Haleakala
76  * boards (256 MiB w/o ECC memory soldered onto the board) and a
77  * proprietary board based on those designs (128 MiB ECC memory, also
78  * soldered onto the board).
79  *
80  * Dynamic feature detection and handling needs to be added for the
81  * other realizations of this controller listed above.
82  *
83  * Eventually, this driver will likely be adapted to the above variant
84  * realizations of this controller as well as broken apart to handle
85  * the other known ECC-capable controllers prevalent in other 4xx
86  * processors:
87  *
88  *   - IBM SDRAM (405GP, 405CR and 405EP) "ibm,sdram-4xx"
89  *   - IBM DDR1 (440GP, 440GX, 440EP and 440GR) "ibm,sdram-4xx-ddr"
90  *   - Denali DDR1/DDR2 (440EPX and 440GRX) "denali,sdram-4xx-ddr2"
91  *
92  * For this controller, unfortunately, correctable errors report
93  * nothing more than the beat/cycle and byte/lane the correction
94  * occurred on and the check bit group that covered the error.
95  *
96  * In contrast, uncorrectable errors also report the failing address,
97  * the bus master and the transaction direction (i.e. read or write)
98  *
99  * Regardless of whether the error is a CE or a UE, we report the
100  * following pieces of information in the driver-unique message to the
101  * EDAC subsystem:
102  *
103  *   - Device tree path
104  *   - Bank(s)
105  *   - Check bit error group
106  *   - Beat(s)/lane(s)
107  */
108 
109 /* Preprocessor Definitions */
110 
111 #define EDAC_OPSTATE_INT_STR		"interrupt"
112 #define EDAC_OPSTATE_POLL_STR		"polled"
113 #define EDAC_OPSTATE_UNKNOWN_STR	"unknown"
114 
115 #define PPC4XX_EDAC_MODULE_NAME		"ppc4xx_edac"
116 #define PPC4XX_EDAC_MODULE_REVISION	"v1.0.0"
117 
118 #define PPC4XX_EDAC_MESSAGE_SIZE	256
119 
120 /*
121  * Kernel logging without an EDAC instance
122  */
123 #define ppc4xx_edac_printk(level, fmt, arg...) \
124 	edac_printk(level, "PPC4xx MC", fmt, ##arg)
125 
126 /*
127  * Kernel logging with an EDAC instance
128  */
129 #define ppc4xx_edac_mc_printk(level, mci, fmt, arg...) \
130 	edac_mc_chipset_printk(mci, level, "PPC4xx", fmt, ##arg)
131 
132 /*
133  * Macros to convert bank configuration size enumerations into MiB and
134  * page values.
135  */
136 #define SDRAM_MBCF_SZ_MiB_MIN		4
137 #define SDRAM_MBCF_SZ_TO_MiB(n)		(SDRAM_MBCF_SZ_MiB_MIN \
138 					 << (SDRAM_MBCF_SZ_DECODE(n)))
139 #define SDRAM_MBCF_SZ_TO_PAGES(n)	(SDRAM_MBCF_SZ_MiB_MIN \
140 					 << (20 - PAGE_SHIFT + \
141 					     SDRAM_MBCF_SZ_DECODE(n)))
142 
143 /*
144  * The ibm,sdram-4xx-ddr2 Device Control Registers (DCRs) are
145  * indirectly accessed and have a base and length defined by the
146  * device tree. The base can be anything; however, we expect the
147  * length to be precisely two registers, the first for the address
148  * window and the second for the data window.
149  */
150 #define SDRAM_DCR_RESOURCE_LEN		2
151 #define SDRAM_DCR_ADDR_OFFSET		0
152 #define SDRAM_DCR_DATA_OFFSET		1
153 
154 /*
155  * Device tree interrupt indices
156  */
157 #define INTMAP_ECCDED_INDEX		0	/* Double-bit Error Detect */
158 #define INTMAP_ECCSEC_INDEX		1	/* Single-bit Error Correct */
159 
160 /* Type Definitions */
161 
162 /*
163  * PPC4xx SDRAM memory controller private instance data
164  */
165 struct ppc4xx_edac_pdata {
166 	dcr_host_t dcr_host;	/* Indirect DCR address/data window mapping */
167 	struct {
168 		int sec;	/* Single-bit correctable error IRQ assigned */
169 		int ded;	/* Double-bit detectable error IRQ assigned */
170 	} irqs;
171 };
172 
173 /*
174  * Various status data gathered and manipulated when checking and
175  * reporting ECC status.
176  */
177 struct ppc4xx_ecc_status {
178 	u32 ecces;
179 	u32 besr;
180 	u32 bearh;
181 	u32 bearl;
182 	u32 wmirq;
183 };
184 
185 /* Function Prototypes */
186 
187 static int ppc4xx_edac_probe(struct platform_device *device);
188 static int ppc4xx_edac_remove(struct platform_device *device);
189 
190 /* Global Variables */
191 
192 /*
193  * Device tree node type and compatible tuples this driver can match
194  * on.
195  */
196 static const struct of_device_id ppc4xx_edac_match[] = {
197 	{
198 		.compatible	= "ibm,sdram-4xx-ddr2"
199 	},
200 	{ }
201 };
202 
203 static struct platform_driver ppc4xx_edac_driver = {
204 	.probe			= ppc4xx_edac_probe,
205 	.remove			= ppc4xx_edac_remove,
206 	.driver = {
207 		.name = PPC4XX_EDAC_MODULE_NAME,
208 		.of_match_table = ppc4xx_edac_match,
209 	},
210 };
211 
212 /*
213  * TODO: The row and channel parameters likely need to be dynamically
214  * set based on the aforementioned variant controller realizations.
215  */
216 static const unsigned ppc4xx_edac_nr_csrows = 2;
217 static const unsigned ppc4xx_edac_nr_chans = 1;
218 
219 /*
220  * Strings associated with PLB master IDs capable of being posted in
221  * SDRAM_BESR or SDRAM_WMIRQ on uncorrectable ECC errors.
222  */
223 static const char * const ppc4xx_plb_masters[9] = {
224 	[SDRAM_PLB_M0ID_ICU]	= "ICU",
225 	[SDRAM_PLB_M0ID_PCIE0]	= "PCI-E 0",
226 	[SDRAM_PLB_M0ID_PCIE1]	= "PCI-E 1",
227 	[SDRAM_PLB_M0ID_DMA]	= "DMA",
228 	[SDRAM_PLB_M0ID_DCU]	= "DCU",
229 	[SDRAM_PLB_M0ID_OPB]	= "OPB",
230 	[SDRAM_PLB_M0ID_MAL]	= "MAL",
231 	[SDRAM_PLB_M0ID_SEC]	= "SEC",
232 	[SDRAM_PLB_M0ID_AHB]	= "AHB"
233 };
234 
235 /**
236  * mfsdram - read and return controller register data
237  * @dcr_host: A pointer to the DCR mapping.
238  * @idcr_n: The indirect DCR register to read.
239  *
240  * This routine reads and returns the data associated with the
241  * controller's specified indirect DCR register.
242  *
243  * Returns the read data.
244  */
245 static inline u32
246 mfsdram(const dcr_host_t *dcr_host, unsigned int idcr_n)
247 {
248 	return __mfdcri(dcr_host->base + SDRAM_DCR_ADDR_OFFSET,
249 			dcr_host->base + SDRAM_DCR_DATA_OFFSET,
250 			idcr_n);
251 }
252 
253 /**
254  * mtsdram - write controller register data
255  * @dcr_host: A pointer to the DCR mapping.
256  * @idcr_n: The indirect DCR register to write.
257  * @value: The data to write.
258  *
259  * This routine writes the provided data to the controller's specified
260  * indirect DCR register.
261  */
262 static inline void
263 mtsdram(const dcr_host_t *dcr_host, unsigned int idcr_n, u32 value)
264 {
265 	return __mtdcri(dcr_host->base + SDRAM_DCR_ADDR_OFFSET,
266 			dcr_host->base + SDRAM_DCR_DATA_OFFSET,
267 			idcr_n,
268 			value);
269 }
270 
271 /**
272  * ppc4xx_edac_check_bank_error - check a bank for an ECC bank error
273  * @status: A pointer to the ECC status structure to check for an
274  *          ECC bank error.
275  * @bank: The bank to check for an ECC error.
276  *
277  * This routine determines whether the specified bank has an ECC
278  * error.
279  *
280  * Returns true if the specified bank has an ECC error; otherwise,
281  * false.
282  */
283 static bool
284 ppc4xx_edac_check_bank_error(const struct ppc4xx_ecc_status *status,
285 			     unsigned int bank)
286 {
287 	switch (bank) {
288 	case 0:
289 		return status->ecces & SDRAM_ECCES_BK0ER;
290 	case 1:
291 		return status->ecces & SDRAM_ECCES_BK1ER;
292 	default:
293 		return false;
294 	}
295 }
296 
297 /**
298  * ppc4xx_edac_generate_bank_message - generate interpretted bank status message
299  * @mci: A pointer to the EDAC memory controller instance associated
300  *       with the bank message being generated.
301  * @status: A pointer to the ECC status structure to generate the
302  *          message from.
303  * @buffer: A pointer to the buffer in which to generate the
304  *          message.
305  * @size: The size, in bytes, of space available in buffer.
306  *
307  * This routine generates to the provided buffer the portion of the
308  * driver-unique report message associated with the ECCESS[BKNER]
309  * field of the specified ECC status.
310  *
311  * Returns the number of characters generated on success; otherwise, <
312  * 0 on error.
313  */
314 static int
315 ppc4xx_edac_generate_bank_message(const struct mem_ctl_info *mci,
316 				  const struct ppc4xx_ecc_status *status,
317 				  char *buffer,
318 				  size_t size)
319 {
320 	int n, total = 0;
321 	unsigned int row, rows;
322 
323 	n = snprintf(buffer, size, "%s: Banks: ", mci->dev_name);
324 
325 	if (n < 0 || n >= size)
326 		goto fail;
327 
328 	buffer += n;
329 	size -= n;
330 	total += n;
331 
332 	for (rows = 0, row = 0; row < mci->nr_csrows; row++) {
333 		if (ppc4xx_edac_check_bank_error(status, row)) {
334 			n = snprintf(buffer, size, "%s%u",
335 					(rows++ ? ", " : ""), row);
336 
337 			if (n < 0 || n >= size)
338 				goto fail;
339 
340 			buffer += n;
341 			size -= n;
342 			total += n;
343 		}
344 	}
345 
346 	n = snprintf(buffer, size, "%s; ", rows ? "" : "None");
347 
348 	if (n < 0 || n >= size)
349 		goto fail;
350 
351 	buffer += n;
352 	size -= n;
353 	total += n;
354 
355  fail:
356 	return total;
357 }
358 
359 /**
360  * ppc4xx_edac_generate_checkbit_message - generate interpretted checkbit message
361  * @mci: A pointer to the EDAC memory controller instance associated
362  *       with the checkbit message being generated.
363  * @status: A pointer to the ECC status structure to generate the
364  *          message from.
365  * @buffer: A pointer to the buffer in which to generate the
366  *          message.
367  * @size: The size, in bytes, of space available in buffer.
368  *
369  * This routine generates to the provided buffer the portion of the
370  * driver-unique report message associated with the ECCESS[CKBER]
371  * field of the specified ECC status.
372  *
373  * Returns the number of characters generated on success; otherwise, <
374  * 0 on error.
375  */
376 static int
377 ppc4xx_edac_generate_checkbit_message(const struct mem_ctl_info *mci,
378 				      const struct ppc4xx_ecc_status *status,
379 				      char *buffer,
380 				      size_t size)
381 {
382 	const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
383 	const char *ckber = NULL;
384 
385 	switch (status->ecces & SDRAM_ECCES_CKBER_MASK) {
386 	case SDRAM_ECCES_CKBER_NONE:
387 		ckber = "None";
388 		break;
389 	case SDRAM_ECCES_CKBER_32_ECC_0_3:
390 		ckber = "ECC0:3";
391 		break;
392 	case SDRAM_ECCES_CKBER_32_ECC_4_8:
393 		switch (mfsdram(&pdata->dcr_host, SDRAM_MCOPT1) &
394 			SDRAM_MCOPT1_WDTH_MASK) {
395 		case SDRAM_MCOPT1_WDTH_16:
396 			ckber = "ECC0:3";
397 			break;
398 		case SDRAM_MCOPT1_WDTH_32:
399 			ckber = "ECC4:8";
400 			break;
401 		default:
402 			ckber = "Unknown";
403 			break;
404 		}
405 		break;
406 	case SDRAM_ECCES_CKBER_32_ECC_0_8:
407 		ckber = "ECC0:8";
408 		break;
409 	default:
410 		ckber = "Unknown";
411 		break;
412 	}
413 
414 	return snprintf(buffer, size, "Checkbit Error: %s", ckber);
415 }
416 
417 /**
418  * ppc4xx_edac_generate_lane_message - generate interpretted byte lane message
419  * @mci: A pointer to the EDAC memory controller instance associated
420  *       with the byte lane message being generated.
421  * @status: A pointer to the ECC status structure to generate the
422  *          message from.
423  * @buffer: A pointer to the buffer in which to generate the
424  *          message.
425  * @size: The size, in bytes, of space available in buffer.
426  *
427  * This routine generates to the provided buffer the portion of the
428  * driver-unique report message associated with the ECCESS[BNCE]
429  * field of the specified ECC status.
430  *
431  * Returns the number of characters generated on success; otherwise, <
432  * 0 on error.
433  */
434 static int
435 ppc4xx_edac_generate_lane_message(const struct mem_ctl_info *mci,
436 				  const struct ppc4xx_ecc_status *status,
437 				  char *buffer,
438 				  size_t size)
439 {
440 	int n, total = 0;
441 	unsigned int lane, lanes;
442 	const unsigned int first_lane = 0;
443 	const unsigned int lane_count = 16;
444 
445 	n = snprintf(buffer, size, "; Byte Lane Errors: ");
446 
447 	if (n < 0 || n >= size)
448 		goto fail;
449 
450 	buffer += n;
451 	size -= n;
452 	total += n;
453 
454 	for (lanes = 0, lane = first_lane; lane < lane_count; lane++) {
455 		if ((status->ecces & SDRAM_ECCES_BNCE_ENCODE(lane)) != 0) {
456 			n = snprintf(buffer, size,
457 				     "%s%u",
458 				     (lanes++ ? ", " : ""), lane);
459 
460 			if (n < 0 || n >= size)
461 				goto fail;
462 
463 			buffer += n;
464 			size -= n;
465 			total += n;
466 		}
467 	}
468 
469 	n = snprintf(buffer, size, "%s; ", lanes ? "" : "None");
470 
471 	if (n < 0 || n >= size)
472 		goto fail;
473 
474 	buffer += n;
475 	size -= n;
476 	total += n;
477 
478  fail:
479 	return total;
480 }
481 
482 /**
483  * ppc4xx_edac_generate_ecc_message - generate interpretted ECC status message
484  * @mci: A pointer to the EDAC memory controller instance associated
485  *       with the ECCES message being generated.
486  * @status: A pointer to the ECC status structure to generate the
487  *          message from.
488  * @buffer: A pointer to the buffer in which to generate the
489  *          message.
490  * @size: The size, in bytes, of space available in buffer.
491  *
492  * This routine generates to the provided buffer the portion of the
493  * driver-unique report message associated with the ECCESS register of
494  * the specified ECC status.
495  *
496  * Returns the number of characters generated on success; otherwise, <
497  * 0 on error.
498  */
499 static int
500 ppc4xx_edac_generate_ecc_message(const struct mem_ctl_info *mci,
501 				 const struct ppc4xx_ecc_status *status,
502 				 char *buffer,
503 				 size_t size)
504 {
505 	int n, total = 0;
506 
507 	n = ppc4xx_edac_generate_bank_message(mci, status, buffer, size);
508 
509 	if (n < 0 || n >= size)
510 		goto fail;
511 
512 	buffer += n;
513 	size -= n;
514 	total += n;
515 
516 	n = ppc4xx_edac_generate_checkbit_message(mci, status, buffer, size);
517 
518 	if (n < 0 || n >= size)
519 		goto fail;
520 
521 	buffer += n;
522 	size -= n;
523 	total += n;
524 
525 	n = ppc4xx_edac_generate_lane_message(mci, status, buffer, size);
526 
527 	if (n < 0 || n >= size)
528 		goto fail;
529 
530 	buffer += n;
531 	size -= n;
532 	total += n;
533 
534  fail:
535 	return total;
536 }
537 
538 /**
539  * ppc4xx_edac_generate_plb_message - generate interpretted PLB status message
540  * @mci: A pointer to the EDAC memory controller instance associated
541  *       with the PLB message being generated.
542  * @status: A pointer to the ECC status structure to generate the
543  *          message from.
544  * @buffer: A pointer to the buffer in which to generate the
545  *          message.
546  * @size: The size, in bytes, of space available in buffer.
547  *
548  * This routine generates to the provided buffer the portion of the
549  * driver-unique report message associated with the PLB-related BESR
550  * and/or WMIRQ registers of the specified ECC status.
551  *
552  * Returns the number of characters generated on success; otherwise, <
553  * 0 on error.
554  */
555 static int
556 ppc4xx_edac_generate_plb_message(const struct mem_ctl_info *mci,
557 				 const struct ppc4xx_ecc_status *status,
558 				 char *buffer,
559 				 size_t size)
560 {
561 	unsigned int master;
562 	bool read;
563 
564 	if ((status->besr & SDRAM_BESR_MASK) == 0)
565 		return 0;
566 
567 	if ((status->besr & SDRAM_BESR_M0ET_MASK) == SDRAM_BESR_M0ET_NONE)
568 		return 0;
569 
570 	read = ((status->besr & SDRAM_BESR_M0RW_MASK) == SDRAM_BESR_M0RW_READ);
571 
572 	master = SDRAM_BESR_M0ID_DECODE(status->besr);
573 
574 	return snprintf(buffer, size,
575 			"%s error w/ PLB master %u \"%s\"; ",
576 			(read ? "Read" : "Write"),
577 			master,
578 			(((master >= SDRAM_PLB_M0ID_FIRST) &&
579 			  (master <= SDRAM_PLB_M0ID_LAST)) ?
580 			 ppc4xx_plb_masters[master] : "UNKNOWN"));
581 }
582 
583 /**
584  * ppc4xx_edac_generate_message - generate interpretted status message
585  * @mci: A pointer to the EDAC memory controller instance associated
586  *       with the driver-unique message being generated.
587  * @status: A pointer to the ECC status structure to generate the
588  *          message from.
589  * @buffer: A pointer to the buffer in which to generate the
590  *          message.
591  * @size: The size, in bytes, of space available in buffer.
592  *
593  * This routine generates to the provided buffer the driver-unique
594  * EDAC report message from the specified ECC status.
595  */
596 static void
597 ppc4xx_edac_generate_message(const struct mem_ctl_info *mci,
598 			     const struct ppc4xx_ecc_status *status,
599 			     char *buffer,
600 			     size_t size)
601 {
602 	int n;
603 
604 	if (buffer == NULL || size == 0)
605 		return;
606 
607 	n = ppc4xx_edac_generate_ecc_message(mci, status, buffer, size);
608 
609 	if (n < 0 || n >= size)
610 		return;
611 
612 	buffer += n;
613 	size -= n;
614 
615 	ppc4xx_edac_generate_plb_message(mci, status, buffer, size);
616 }
617 
618 #ifdef DEBUG
619 /**
620  * ppc4xx_ecc_dump_status - dump controller ECC status registers
621  * @mci: A pointer to the EDAC memory controller instance
622  *       associated with the status being dumped.
623  * @status: A pointer to the ECC status structure to generate the
624  *          dump from.
625  *
626  * This routine dumps to the kernel log buffer the raw and
627  * interpretted specified ECC status.
628  */
629 static void
630 ppc4xx_ecc_dump_status(const struct mem_ctl_info *mci,
631 		       const struct ppc4xx_ecc_status *status)
632 {
633 	char message[PPC4XX_EDAC_MESSAGE_SIZE];
634 
635 	ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
636 
637 	ppc4xx_edac_mc_printk(KERN_INFO, mci,
638 			      "\n"
639 			      "\tECCES: 0x%08x\n"
640 			      "\tWMIRQ: 0x%08x\n"
641 			      "\tBESR:  0x%08x\n"
642 			      "\tBEAR:  0x%08x%08x\n"
643 			      "\t%s\n",
644 			      status->ecces,
645 			      status->wmirq,
646 			      status->besr,
647 			      status->bearh,
648 			      status->bearl,
649 			      message);
650 }
651 #endif /* DEBUG */
652 
653 /**
654  * ppc4xx_ecc_get_status - get controller ECC status
655  * @mci: A pointer to the EDAC memory controller instance
656  *       associated with the status being retrieved.
657  * @status: A pointer to the ECC status structure to populate the
658  *          ECC status with.
659  *
660  * This routine reads and masks, as appropriate, all the relevant
661  * status registers that deal with ibm,sdram-4xx-ddr2 ECC errors.
662  * While we read all of them, for correctable errors, we only expect
663  * to deal with ECCES. For uncorrectable errors, we expect to deal
664  * with all of them.
665  */
666 static void
667 ppc4xx_ecc_get_status(const struct mem_ctl_info *mci,
668 		      struct ppc4xx_ecc_status *status)
669 {
670 	const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
671 	const dcr_host_t *dcr_host = &pdata->dcr_host;
672 
673 	status->ecces = mfsdram(dcr_host, SDRAM_ECCES) & SDRAM_ECCES_MASK;
674 	status->wmirq = mfsdram(dcr_host, SDRAM_WMIRQ) & SDRAM_WMIRQ_MASK;
675 	status->besr  = mfsdram(dcr_host, SDRAM_BESR)  & SDRAM_BESR_MASK;
676 	status->bearl = mfsdram(dcr_host, SDRAM_BEARL);
677 	status->bearh = mfsdram(dcr_host, SDRAM_BEARH);
678 }
679 
680 /**
681  * ppc4xx_ecc_clear_status - clear controller ECC status
682  * @mci: A pointer to the EDAC memory controller instance
683  *       associated with the status being cleared.
684  * @status: A pointer to the ECC status structure containing the
685  *          values to write to clear the ECC status.
686  *
687  * This routine clears--by writing the masked (as appropriate) status
688  * values back to--the status registers that deal with
689  * ibm,sdram-4xx-ddr2 ECC errors.
690  */
691 static void
692 ppc4xx_ecc_clear_status(const struct mem_ctl_info *mci,
693 			const struct ppc4xx_ecc_status *status)
694 {
695 	const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
696 	const dcr_host_t *dcr_host = &pdata->dcr_host;
697 
698 	mtsdram(dcr_host, SDRAM_ECCES,	status->ecces & SDRAM_ECCES_MASK);
699 	mtsdram(dcr_host, SDRAM_WMIRQ,	status->wmirq & SDRAM_WMIRQ_MASK);
700 	mtsdram(dcr_host, SDRAM_BESR,	status->besr & SDRAM_BESR_MASK);
701 	mtsdram(dcr_host, SDRAM_BEARL,	0);
702 	mtsdram(dcr_host, SDRAM_BEARH,	0);
703 }
704 
705 /**
706  * ppc4xx_edac_handle_ce - handle controller correctable ECC error (CE)
707  * @mci: A pointer to the EDAC memory controller instance
708  *       associated with the correctable error being handled and reported.
709  * @status: A pointer to the ECC status structure associated with
710  *          the correctable error being handled and reported.
711  *
712  * This routine handles an ibm,sdram-4xx-ddr2 controller ECC
713  * correctable error. Per the aforementioned discussion, there's not
714  * enough status available to use the full EDAC correctable error
715  * interface, so we just pass driver-unique message to the "no info"
716  * interface.
717  */
718 static void
719 ppc4xx_edac_handle_ce(struct mem_ctl_info *mci,
720 		      const struct ppc4xx_ecc_status *status)
721 {
722 	int row;
723 	char message[PPC4XX_EDAC_MESSAGE_SIZE];
724 
725 	ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
726 
727 	for (row = 0; row < mci->nr_csrows; row++)
728 		if (ppc4xx_edac_check_bank_error(status, row))
729 			edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
730 					     0, 0, 0,
731 					     row, 0, -1,
732 					     message, "");
733 }
734 
735 /**
736  * ppc4xx_edac_handle_ue - handle controller uncorrectable ECC error (UE)
737  * @mci: A pointer to the EDAC memory controller instance
738  *       associated with the uncorrectable error being handled and
739  *       reported.
740  * @status: A pointer to the ECC status structure associated with
741  *          the uncorrectable error being handled and reported.
742  *
743  * This routine handles an ibm,sdram-4xx-ddr2 controller ECC
744  * uncorrectable error.
745  */
746 static void
747 ppc4xx_edac_handle_ue(struct mem_ctl_info *mci,
748 		      const struct ppc4xx_ecc_status *status)
749 {
750 	const u64 bear = ((u64)status->bearh << 32 | status->bearl);
751 	const unsigned long page = bear >> PAGE_SHIFT;
752 	const unsigned long offset = bear & ~PAGE_MASK;
753 	int row;
754 	char message[PPC4XX_EDAC_MESSAGE_SIZE];
755 
756 	ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
757 
758 	for (row = 0; row < mci->nr_csrows; row++)
759 		if (ppc4xx_edac_check_bank_error(status, row))
760 			edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
761 					     page, offset, 0,
762 					     row, 0, -1,
763 					     message, "");
764 }
765 
766 /**
767  * ppc4xx_edac_check - check controller for ECC errors
768  * @mci: A pointer to the EDAC memory controller instance
769  *       associated with the ibm,sdram-4xx-ddr2 controller being
770  *       checked.
771  *
772  * This routine is used to check and post ECC errors and is called by
773  * both the EDAC polling thread and this driver's CE and UE interrupt
774  * handler.
775  */
776 static void
777 ppc4xx_edac_check(struct mem_ctl_info *mci)
778 {
779 #ifdef DEBUG
780 	static unsigned int count;
781 #endif
782 	struct ppc4xx_ecc_status status;
783 
784 	ppc4xx_ecc_get_status(mci, &status);
785 
786 #ifdef DEBUG
787 	if (count++ % 30 == 0)
788 		ppc4xx_ecc_dump_status(mci, &status);
789 #endif
790 
791 	if (status.ecces & SDRAM_ECCES_UE)
792 		ppc4xx_edac_handle_ue(mci, &status);
793 
794 	if (status.ecces & SDRAM_ECCES_CE)
795 		ppc4xx_edac_handle_ce(mci, &status);
796 
797 	ppc4xx_ecc_clear_status(mci, &status);
798 }
799 
800 /**
801  * ppc4xx_edac_isr - SEC (CE) and DED (UE) interrupt service routine
802  * @irq:    The virtual interrupt number being serviced.
803  * @dev_id: A pointer to the EDAC memory controller instance
804  *          associated with the interrupt being handled.
805  *
806  * This routine implements the interrupt handler for both correctable
807  * (CE) and uncorrectable (UE) ECC errors for the ibm,sdram-4xx-ddr2
808  * controller. It simply calls through to the same routine used during
809  * polling to check, report and clear the ECC status.
810  *
811  * Unconditionally returns IRQ_HANDLED.
812  */
813 static irqreturn_t
814 ppc4xx_edac_isr(int irq, void *dev_id)
815 {
816 	struct mem_ctl_info *mci = dev_id;
817 
818 	ppc4xx_edac_check(mci);
819 
820 	return IRQ_HANDLED;
821 }
822 
823 /**
824  * ppc4xx_edac_get_dtype - return the controller memory width
825  * @mcopt1: The 32-bit Memory Controller Option 1 register value
826  *          currently set for the controller, from which the width
827  *          is derived.
828  *
829  * This routine returns the EDAC device type width appropriate for the
830  * current controller configuration.
831  *
832  * TODO: This needs to be conditioned dynamically through feature
833  * flags or some such when other controller variants are supported as
834  * the 405EX[r] is 16-/32-bit and the others are 32-/64-bit with the
835  * 16- and 64-bit field definition/value/enumeration (b1) overloaded
836  * among them.
837  *
838  * Returns a device type width enumeration.
839  */
840 static enum dev_type ppc4xx_edac_get_dtype(u32 mcopt1)
841 {
842 	switch (mcopt1 & SDRAM_MCOPT1_WDTH_MASK) {
843 	case SDRAM_MCOPT1_WDTH_16:
844 		return DEV_X2;
845 	case SDRAM_MCOPT1_WDTH_32:
846 		return DEV_X4;
847 	default:
848 		return DEV_UNKNOWN;
849 	}
850 }
851 
852 /**
853  * ppc4xx_edac_get_mtype - return controller memory type
854  * @mcopt1: The 32-bit Memory Controller Option 1 register value
855  *          currently set for the controller, from which the memory type
856  *          is derived.
857  *
858  * This routine returns the EDAC memory type appropriate for the
859  * current controller configuration.
860  *
861  * Returns a memory type enumeration.
862  */
863 static enum mem_type ppc4xx_edac_get_mtype(u32 mcopt1)
864 {
865 	bool rden = ((mcopt1 & SDRAM_MCOPT1_RDEN_MASK) == SDRAM_MCOPT1_RDEN);
866 
867 	switch (mcopt1 & SDRAM_MCOPT1_DDR_TYPE_MASK) {
868 	case SDRAM_MCOPT1_DDR2_TYPE:
869 		return rden ? MEM_RDDR2 : MEM_DDR2;
870 	case SDRAM_MCOPT1_DDR1_TYPE:
871 		return rden ? MEM_RDDR : MEM_DDR;
872 	default:
873 		return MEM_UNKNOWN;
874 	}
875 }
876 
877 /**
878  * ppc4xx_edac_init_csrows - initialize driver instance rows
879  * @mci: A pointer to the EDAC memory controller instance
880  *       associated with the ibm,sdram-4xx-ddr2 controller for which
881  *       the csrows (i.e. banks/ranks) are being initialized.
882  * @mcopt1: The 32-bit Memory Controller Option 1 register value
883  *          currently set for the controller, from which bank width
884  *          and memory typ information is derived.
885  *
886  * This routine initializes the virtual "chip select rows" associated
887  * with the EDAC memory controller instance. An ibm,sdram-4xx-ddr2
888  * controller bank/rank is mapped to a row.
889  *
890  * Returns 0 if OK; otherwise, -EINVAL if the memory bank size
891  * configuration cannot be determined.
892  */
893 static int ppc4xx_edac_init_csrows(struct mem_ctl_info *mci, u32 mcopt1)
894 {
895 	const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
896 	int status = 0;
897 	enum mem_type mtype;
898 	enum dev_type dtype;
899 	enum edac_type edac_mode;
900 	int row, j;
901 	u32 mbxcf, size, nr_pages;
902 
903 	/* Establish the memory type and width */
904 
905 	mtype = ppc4xx_edac_get_mtype(mcopt1);
906 	dtype = ppc4xx_edac_get_dtype(mcopt1);
907 
908 	/* Establish EDAC mode */
909 
910 	if (mci->edac_cap & EDAC_FLAG_SECDED)
911 		edac_mode = EDAC_SECDED;
912 	else if (mci->edac_cap & EDAC_FLAG_EC)
913 		edac_mode = EDAC_EC;
914 	else
915 		edac_mode = EDAC_NONE;
916 
917 	/*
918 	 * Initialize each chip select row structure which correspond
919 	 * 1:1 with a controller bank/rank.
920 	 */
921 
922 	for (row = 0; row < mci->nr_csrows; row++) {
923 		struct csrow_info *csi = mci->csrows[row];
924 
925 		/*
926 		 * Get the configuration settings for this
927 		 * row/bank/rank and skip disabled banks.
928 		 */
929 
930 		mbxcf = mfsdram(&pdata->dcr_host, SDRAM_MBXCF(row));
931 
932 		if ((mbxcf & SDRAM_MBCF_BE_MASK) != SDRAM_MBCF_BE_ENABLE)
933 			continue;
934 
935 		/* Map the bank configuration size setting to pages. */
936 
937 		size = mbxcf & SDRAM_MBCF_SZ_MASK;
938 
939 		switch (size) {
940 		case SDRAM_MBCF_SZ_4MB:
941 		case SDRAM_MBCF_SZ_8MB:
942 		case SDRAM_MBCF_SZ_16MB:
943 		case SDRAM_MBCF_SZ_32MB:
944 		case SDRAM_MBCF_SZ_64MB:
945 		case SDRAM_MBCF_SZ_128MB:
946 		case SDRAM_MBCF_SZ_256MB:
947 		case SDRAM_MBCF_SZ_512MB:
948 		case SDRAM_MBCF_SZ_1GB:
949 		case SDRAM_MBCF_SZ_2GB:
950 		case SDRAM_MBCF_SZ_4GB:
951 		case SDRAM_MBCF_SZ_8GB:
952 			nr_pages = SDRAM_MBCF_SZ_TO_PAGES(size);
953 			break;
954 		default:
955 			ppc4xx_edac_mc_printk(KERN_ERR, mci,
956 					      "Unrecognized memory bank %d "
957 					      "size 0x%08x\n",
958 					      row, SDRAM_MBCF_SZ_DECODE(size));
959 			status = -EINVAL;
960 			goto done;
961 		}
962 
963 		/*
964 		 * It's unclear exactly what grain should be set to
965 		 * here. The SDRAM_ECCES register allows resolution of
966 		 * an error down to a nibble which would potentially
967 		 * argue for a grain of '1' byte, even though we only
968 		 * know the associated address for uncorrectable
969 		 * errors. This value is not used at present for
970 		 * anything other than error reporting so getting it
971 		 * wrong should be of little consequence. Other
972 		 * possible values would be the PLB width (16), the
973 		 * page size (PAGE_SIZE) or the memory width (2 or 4).
974 		 */
975 		for (j = 0; j < csi->nr_channels; j++) {
976 			struct dimm_info *dimm = csi->channels[j]->dimm;
977 
978 			dimm->nr_pages  = nr_pages / csi->nr_channels;
979 			dimm->grain	= 1;
980 
981 			dimm->mtype	= mtype;
982 			dimm->dtype	= dtype;
983 
984 			dimm->edac_mode	= edac_mode;
985 		}
986 	}
987 
988  done:
989 	return status;
990 }
991 
992 /**
993  * ppc4xx_edac_mc_init - initialize driver instance
994  * @mci: A pointer to the EDAC memory controller instance being
995  *       initialized.
996  * @op: A pointer to the OpenFirmware device tree node associated
997  *      with the controller this EDAC instance is bound to.
998  * @dcr_host: A pointer to the DCR data containing the DCR mapping
999  *            for this controller instance.
1000  * @mcopt1: The 32-bit Memory Controller Option 1 register value
1001  *          currently set for the controller, from which ECC capabilities
1002  *          and scrub mode are derived.
1003  *
1004  * This routine performs initialization of the EDAC memory controller
1005  * instance and related driver-private data associated with the
1006  * ibm,sdram-4xx-ddr2 memory controller the instance is bound to.
1007  *
1008  * Returns 0 if OK; otherwise, < 0 on error.
1009  */
1010 static int ppc4xx_edac_mc_init(struct mem_ctl_info *mci,
1011 			       struct platform_device *op,
1012 			       const dcr_host_t *dcr_host, u32 mcopt1)
1013 {
1014 	int status = 0;
1015 	const u32 memcheck = (mcopt1 & SDRAM_MCOPT1_MCHK_MASK);
1016 	struct ppc4xx_edac_pdata *pdata = NULL;
1017 	const struct device_node *np = op->dev.of_node;
1018 
1019 	if (of_match_device(ppc4xx_edac_match, &op->dev) == NULL)
1020 		return -EINVAL;
1021 
1022 	/* Initial driver pointers and private data */
1023 
1024 	mci->pdev		= &op->dev;
1025 
1026 	dev_set_drvdata(mci->pdev, mci);
1027 
1028 	pdata			= mci->pvt_info;
1029 
1030 	pdata->dcr_host		= *dcr_host;
1031 	pdata->irqs.sec		= NO_IRQ;
1032 	pdata->irqs.ded		= NO_IRQ;
1033 
1034 	/* Initialize controller capabilities and configuration */
1035 
1036 	mci->mtype_cap		= (MEM_FLAG_DDR | MEM_FLAG_RDDR |
1037 				   MEM_FLAG_DDR2 | MEM_FLAG_RDDR2);
1038 
1039 	mci->edac_ctl_cap	= (EDAC_FLAG_NONE |
1040 				   EDAC_FLAG_EC |
1041 				   EDAC_FLAG_SECDED);
1042 
1043 	mci->scrub_cap		= SCRUB_NONE;
1044 	mci->scrub_mode		= SCRUB_NONE;
1045 
1046 	/*
1047 	 * Update the actual capabilites based on the MCOPT1[MCHK]
1048 	 * settings. Scrubbing is only useful if reporting is enabled.
1049 	 */
1050 
1051 	switch (memcheck) {
1052 	case SDRAM_MCOPT1_MCHK_CHK:
1053 		mci->edac_cap	= EDAC_FLAG_EC;
1054 		break;
1055 	case SDRAM_MCOPT1_MCHK_CHK_REP:
1056 		mci->edac_cap	= (EDAC_FLAG_EC | EDAC_FLAG_SECDED);
1057 		mci->scrub_mode	= SCRUB_SW_SRC;
1058 		break;
1059 	default:
1060 		mci->edac_cap	= EDAC_FLAG_NONE;
1061 		break;
1062 	}
1063 
1064 	/* Initialize strings */
1065 
1066 	mci->mod_name		= PPC4XX_EDAC_MODULE_NAME;
1067 	mci->mod_ver		= PPC4XX_EDAC_MODULE_REVISION;
1068 	mci->ctl_name		= ppc4xx_edac_match->compatible,
1069 	mci->dev_name		= np->full_name;
1070 
1071 	/* Initialize callbacks */
1072 
1073 	mci->edac_check		= ppc4xx_edac_check;
1074 	mci->ctl_page_to_phys	= NULL;
1075 
1076 	/* Initialize chip select rows */
1077 
1078 	status = ppc4xx_edac_init_csrows(mci, mcopt1);
1079 
1080 	if (status)
1081 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1082 				      "Failed to initialize rows!\n");
1083 
1084 	return status;
1085 }
1086 
1087 /**
1088  * ppc4xx_edac_register_irq - setup and register controller interrupts
1089  * @op: A pointer to the OpenFirmware device tree node associated
1090  *      with the controller this EDAC instance is bound to.
1091  * @mci: A pointer to the EDAC memory controller instance
1092  *       associated with the ibm,sdram-4xx-ddr2 controller for which
1093  *       interrupts are being registered.
1094  *
1095  * This routine parses the correctable (CE) and uncorrectable error (UE)
1096  * interrupts from the device tree node and maps and assigns them to
1097  * the associated EDAC memory controller instance.
1098  *
1099  * Returns 0 if OK; otherwise, -ENODEV if the interrupts could not be
1100  * mapped and assigned.
1101  */
1102 static int ppc4xx_edac_register_irq(struct platform_device *op,
1103 				    struct mem_ctl_info *mci)
1104 {
1105 	int status = 0;
1106 	int ded_irq, sec_irq;
1107 	struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
1108 	struct device_node *np = op->dev.of_node;
1109 
1110 	ded_irq = irq_of_parse_and_map(np, INTMAP_ECCDED_INDEX);
1111 	sec_irq = irq_of_parse_and_map(np, INTMAP_ECCSEC_INDEX);
1112 
1113 	if (ded_irq == NO_IRQ || sec_irq == NO_IRQ) {
1114 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1115 				      "Unable to map interrupts.\n");
1116 		status = -ENODEV;
1117 		goto fail;
1118 	}
1119 
1120 	status = request_irq(ded_irq,
1121 			     ppc4xx_edac_isr,
1122 			     0,
1123 			     "[EDAC] MC ECCDED",
1124 			     mci);
1125 
1126 	if (status < 0) {
1127 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1128 				      "Unable to request irq %d for ECC DED",
1129 				      ded_irq);
1130 		status = -ENODEV;
1131 		goto fail1;
1132 	}
1133 
1134 	status = request_irq(sec_irq,
1135 			     ppc4xx_edac_isr,
1136 			     0,
1137 			     "[EDAC] MC ECCSEC",
1138 			     mci);
1139 
1140 	if (status < 0) {
1141 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1142 				      "Unable to request irq %d for ECC SEC",
1143 				      sec_irq);
1144 		status = -ENODEV;
1145 		goto fail2;
1146 	}
1147 
1148 	ppc4xx_edac_mc_printk(KERN_INFO, mci, "ECCDED irq is %d\n", ded_irq);
1149 	ppc4xx_edac_mc_printk(KERN_INFO, mci, "ECCSEC irq is %d\n", sec_irq);
1150 
1151 	pdata->irqs.ded = ded_irq;
1152 	pdata->irqs.sec = sec_irq;
1153 
1154 	return 0;
1155 
1156  fail2:
1157 	free_irq(sec_irq, mci);
1158 
1159  fail1:
1160 	free_irq(ded_irq, mci);
1161 
1162  fail:
1163 	return status;
1164 }
1165 
1166 /**
1167  * ppc4xx_edac_map_dcrs - locate and map controller registers
1168  * @np: A pointer to the device tree node containing the DCR
1169  *      resources to map.
1170  * @dcr_host: A pointer to the DCR data to populate with the
1171  *            DCR mapping.
1172  *
1173  * This routine attempts to locate in the device tree and map the DCR
1174  * register resources associated with the controller's indirect DCR
1175  * address and data windows.
1176  *
1177  * Returns 0 if the DCRs were successfully mapped; otherwise, < 0 on
1178  * error.
1179  */
1180 static int ppc4xx_edac_map_dcrs(const struct device_node *np,
1181 				dcr_host_t *dcr_host)
1182 {
1183 	unsigned int dcr_base, dcr_len;
1184 
1185 	if (np == NULL || dcr_host == NULL)
1186 		return -EINVAL;
1187 
1188 	/* Get the DCR resource extent and sanity check the values. */
1189 
1190 	dcr_base = dcr_resource_start(np, 0);
1191 	dcr_len = dcr_resource_len(np, 0);
1192 
1193 	if (dcr_base == 0 || dcr_len == 0) {
1194 		ppc4xx_edac_printk(KERN_ERR,
1195 				   "Failed to obtain DCR property.\n");
1196 		return -ENODEV;
1197 	}
1198 
1199 	if (dcr_len != SDRAM_DCR_RESOURCE_LEN) {
1200 		ppc4xx_edac_printk(KERN_ERR,
1201 				   "Unexpected DCR length %d, expected %d.\n",
1202 				   dcr_len, SDRAM_DCR_RESOURCE_LEN);
1203 		return -ENODEV;
1204 	}
1205 
1206 	/*  Attempt to map the DCR extent. */
1207 
1208 	*dcr_host = dcr_map(np, dcr_base, dcr_len);
1209 
1210 	if (!DCR_MAP_OK(*dcr_host)) {
1211 		ppc4xx_edac_printk(KERN_INFO, "Failed to map DCRs.\n");
1212 		    return -ENODEV;
1213 	}
1214 
1215 	return 0;
1216 }
1217 
1218 /**
1219  * ppc4xx_edac_probe - check controller and bind driver
1220  * @op: A pointer to the OpenFirmware device tree node associated
1221  *      with the controller being probed for driver binding.
1222  *
1223  * This routine probes a specific ibm,sdram-4xx-ddr2 controller
1224  * instance for binding with the driver.
1225  *
1226  * Returns 0 if the controller instance was successfully bound to the
1227  * driver; otherwise, < 0 on error.
1228  */
1229 static int ppc4xx_edac_probe(struct platform_device *op)
1230 {
1231 	int status = 0;
1232 	u32 mcopt1, memcheck;
1233 	dcr_host_t dcr_host;
1234 	const struct device_node *np = op->dev.of_node;
1235 	struct mem_ctl_info *mci = NULL;
1236 	struct edac_mc_layer layers[2];
1237 	static int ppc4xx_edac_instance;
1238 
1239 	/*
1240 	 * At this point, we only support the controller realized on
1241 	 * the AMCC PPC 405EX[r]. Reject anything else.
1242 	 */
1243 
1244 	if (!of_device_is_compatible(np, "ibm,sdram-405ex") &&
1245 	    !of_device_is_compatible(np, "ibm,sdram-405exr")) {
1246 		ppc4xx_edac_printk(KERN_NOTICE,
1247 				   "Only the PPC405EX[r] is supported.\n");
1248 		return -ENODEV;
1249 	}
1250 
1251 	/*
1252 	 * Next, get the DCR property and attempt to map it so that we
1253 	 * can probe the controller.
1254 	 */
1255 
1256 	status = ppc4xx_edac_map_dcrs(np, &dcr_host);
1257 
1258 	if (status)
1259 		return status;
1260 
1261 	/*
1262 	 * First determine whether ECC is enabled at all. If not,
1263 	 * there is no useful checking or monitoring that can be done
1264 	 * for this controller.
1265 	 */
1266 
1267 	mcopt1 = mfsdram(&dcr_host, SDRAM_MCOPT1);
1268 	memcheck = (mcopt1 & SDRAM_MCOPT1_MCHK_MASK);
1269 
1270 	if (memcheck == SDRAM_MCOPT1_MCHK_NON) {
1271 		ppc4xx_edac_printk(KERN_INFO, "%s: No ECC memory detected or "
1272 				   "ECC is disabled.\n", np->full_name);
1273 		status = -ENODEV;
1274 		goto done;
1275 	}
1276 
1277 	/*
1278 	 * At this point, we know ECC is enabled, allocate an EDAC
1279 	 * controller instance and perform the appropriate
1280 	 * initialization.
1281 	 */
1282 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
1283 	layers[0].size = ppc4xx_edac_nr_csrows;
1284 	layers[0].is_virt_csrow = true;
1285 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
1286 	layers[1].size = ppc4xx_edac_nr_chans;
1287 	layers[1].is_virt_csrow = false;
1288 	mci = edac_mc_alloc(ppc4xx_edac_instance, ARRAY_SIZE(layers), layers,
1289 			    sizeof(struct ppc4xx_edac_pdata));
1290 	if (mci == NULL) {
1291 		ppc4xx_edac_printk(KERN_ERR, "%s: "
1292 				   "Failed to allocate EDAC MC instance!\n",
1293 				   np->full_name);
1294 		status = -ENOMEM;
1295 		goto done;
1296 	}
1297 
1298 	status = ppc4xx_edac_mc_init(mci, op, &dcr_host, mcopt1);
1299 
1300 	if (status) {
1301 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1302 				      "Failed to initialize instance!\n");
1303 		goto fail;
1304 	}
1305 
1306 	/*
1307 	 * We have a valid, initialized EDAC instance bound to the
1308 	 * controller. Attempt to register it with the EDAC subsystem
1309 	 * and, if necessary, register interrupts.
1310 	 */
1311 
1312 	if (edac_mc_add_mc(mci)) {
1313 		ppc4xx_edac_mc_printk(KERN_ERR, mci,
1314 				      "Failed to add instance!\n");
1315 		status = -ENODEV;
1316 		goto fail;
1317 	}
1318 
1319 	if (edac_op_state == EDAC_OPSTATE_INT) {
1320 		status = ppc4xx_edac_register_irq(op, mci);
1321 
1322 		if (status)
1323 			goto fail1;
1324 	}
1325 
1326 	ppc4xx_edac_instance++;
1327 
1328 	return 0;
1329 
1330  fail1:
1331 	edac_mc_del_mc(mci->pdev);
1332 
1333  fail:
1334 	edac_mc_free(mci);
1335 
1336  done:
1337 	return status;
1338 }
1339 
1340 /**
1341  * ppc4xx_edac_remove - unbind driver from controller
1342  * @op: A pointer to the OpenFirmware device tree node associated
1343  *      with the controller this EDAC instance is to be unbound/removed
1344  *      from.
1345  *
1346  * This routine unbinds the EDAC memory controller instance associated
1347  * with the specified ibm,sdram-4xx-ddr2 controller described by the
1348  * OpenFirmware device tree node passed as a parameter.
1349  *
1350  * Unconditionally returns 0.
1351  */
1352 static int
1353 ppc4xx_edac_remove(struct platform_device *op)
1354 {
1355 	struct mem_ctl_info *mci = dev_get_drvdata(&op->dev);
1356 	struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
1357 
1358 	if (edac_op_state == EDAC_OPSTATE_INT) {
1359 		free_irq(pdata->irqs.sec, mci);
1360 		free_irq(pdata->irqs.ded, mci);
1361 	}
1362 
1363 	dcr_unmap(pdata->dcr_host, SDRAM_DCR_RESOURCE_LEN);
1364 
1365 	edac_mc_del_mc(mci->pdev);
1366 	edac_mc_free(mci);
1367 
1368 	return 0;
1369 }
1370 
1371 /**
1372  * ppc4xx_edac_opstate_init - initialize EDAC reporting method
1373  *
1374  * This routine ensures that the EDAC memory controller reporting
1375  * method is mapped to a sane value as the EDAC core defines the value
1376  * to EDAC_OPSTATE_INVAL by default. We don't call the global
1377  * opstate_init as that defaults to polling and we want interrupt as
1378  * the default.
1379  */
1380 static inline void __init
1381 ppc4xx_edac_opstate_init(void)
1382 {
1383 	switch (edac_op_state) {
1384 	case EDAC_OPSTATE_POLL:
1385 	case EDAC_OPSTATE_INT:
1386 		break;
1387 	default:
1388 		edac_op_state = EDAC_OPSTATE_INT;
1389 		break;
1390 	}
1391 
1392 	ppc4xx_edac_printk(KERN_INFO, "Reporting type: %s\n",
1393 			   ((edac_op_state == EDAC_OPSTATE_POLL) ?
1394 			    EDAC_OPSTATE_POLL_STR :
1395 			    ((edac_op_state == EDAC_OPSTATE_INT) ?
1396 			     EDAC_OPSTATE_INT_STR :
1397 			     EDAC_OPSTATE_UNKNOWN_STR)));
1398 }
1399 
1400 /**
1401  * ppc4xx_edac_init - driver/module insertion entry point
1402  *
1403  * This routine is the driver/module insertion entry point. It
1404  * initializes the EDAC memory controller reporting state and
1405  * registers the driver as an OpenFirmware device tree platform
1406  * driver.
1407  */
1408 static int __init
1409 ppc4xx_edac_init(void)
1410 {
1411 	ppc4xx_edac_printk(KERN_INFO, PPC4XX_EDAC_MODULE_REVISION "\n");
1412 
1413 	ppc4xx_edac_opstate_init();
1414 
1415 	return platform_driver_register(&ppc4xx_edac_driver);
1416 }
1417 
1418 /**
1419  * ppc4xx_edac_exit - driver/module removal entry point
1420  *
1421  * This routine is the driver/module removal entry point. It
1422  * unregisters the driver as an OpenFirmware device tree platform
1423  * driver.
1424  */
1425 static void __exit
1426 ppc4xx_edac_exit(void)
1427 {
1428 	platform_driver_unregister(&ppc4xx_edac_driver);
1429 }
1430 
1431 module_init(ppc4xx_edac_init);
1432 module_exit(ppc4xx_edac_exit);
1433 
1434 MODULE_LICENSE("GPL v2");
1435 MODULE_AUTHOR("Grant Erickson <gerickson@nuovations.com>");
1436 MODULE_DESCRIPTION("EDAC MC Driver for the PPC4xx IBM DDR2 Memory Controller");
1437 module_param(edac_op_state, int, 0444);
1438 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting State: "
1439 		 "0=" EDAC_OPSTATE_POLL_STR ", 2=" EDAC_OPSTATE_INT_STR);
1440