xref: /openbmc/linux/drivers/edac/cpc925_edac.c (revision fd589a8f)
1 /*
2  * cpc925_edac.c, EDAC driver for IBM CPC925 Bridge and Memory Controller.
3  *
4  * Copyright (c) 2008 Wind River Systems, Inc.
5  *
6  * Authors:	Cao Qingtao <qingtao.cao@windriver.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
15  * See the GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21 
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/io.h>
25 #include <linux/edac.h>
26 #include <linux/of.h>
27 #include <linux/platform_device.h>
28 
29 #include "edac_core.h"
30 #include "edac_module.h"
31 
32 #define CPC925_EDAC_REVISION	" Ver: 1.0.0 " __DATE__
33 #define CPC925_EDAC_MOD_STR	"cpc925_edac"
34 
35 #define cpc925_printk(level, fmt, arg...) \
36 	edac_printk(level, "CPC925", fmt, ##arg)
37 
38 #define cpc925_mc_printk(mci, level, fmt, arg...) \
39 	edac_mc_chipset_printk(mci, level, "CPC925", fmt, ##arg)
40 
41 /*
42  * CPC925 registers are of 32 bits with bit0 defined at the
43  * most significant bit and bit31 at that of least significant.
44  */
45 #define CPC925_BITS_PER_REG	32
46 #define CPC925_BIT(nr)		(1UL << (CPC925_BITS_PER_REG - 1 - nr))
47 
48 /*
49  * EDAC device names for the error detections of
50  * CPU Interface and Hypertransport Link.
51  */
52 #define CPC925_CPU_ERR_DEV	"cpu"
53 #define CPC925_HT_LINK_DEV	"htlink"
54 
55 /* Suppose DDR Refresh cycle is 15.6 microsecond */
56 #define CPC925_REF_FREQ		0xFA69
57 #define CPC925_SCRUB_BLOCK_SIZE 64	/* bytes */
58 #define CPC925_NR_CSROWS	8
59 
60 /*
61  * All registers and bits definitions are taken from
62  * "CPC925 Bridge and Memory Controller User Manual, SA14-2761-02".
63  */
64 
65 /*
66  * CPU and Memory Controller Registers
67  */
68 /************************************************************
69  *	Processor Interface Exception Mask Register (APIMASK)
70  ************************************************************/
71 #define REG_APIMASK_OFFSET	0x30070
72 enum apimask_bits {
73 	APIMASK_DART	= CPC925_BIT(0), /* DART Exception */
74 	APIMASK_ADI0	= CPC925_BIT(1), /* Handshake Error on PI0_ADI */
75 	APIMASK_ADI1	= CPC925_BIT(2), /* Handshake Error on PI1_ADI */
76 	APIMASK_STAT	= CPC925_BIT(3), /* Status Exception */
77 	APIMASK_DERR	= CPC925_BIT(4), /* Data Error Exception */
78 	APIMASK_ADRS0	= CPC925_BIT(5), /* Addressing Exception on PI0 */
79 	APIMASK_ADRS1	= CPC925_BIT(6), /* Addressing Exception on PI1 */
80 					 /* BIT(7) Reserved */
81 	APIMASK_ECC_UE_H = CPC925_BIT(8), /* UECC upper */
82 	APIMASK_ECC_CE_H = CPC925_BIT(9), /* CECC upper */
83 	APIMASK_ECC_UE_L = CPC925_BIT(10), /* UECC lower */
84 	APIMASK_ECC_CE_L = CPC925_BIT(11), /* CECC lower */
85 
86 	CPU_MASK_ENABLE = (APIMASK_DART | APIMASK_ADI0 | APIMASK_ADI1 |
87 			   APIMASK_STAT | APIMASK_DERR | APIMASK_ADRS0 |
88 			   APIMASK_ADRS1),
89 	ECC_MASK_ENABLE = (APIMASK_ECC_UE_H | APIMASK_ECC_CE_H |
90 			   APIMASK_ECC_UE_L | APIMASK_ECC_CE_L),
91 };
92 
93 /************************************************************
94  *	Processor Interface Exception Register (APIEXCP)
95  ************************************************************/
96 #define REG_APIEXCP_OFFSET	0x30060
97 enum apiexcp_bits {
98 	APIEXCP_DART	= CPC925_BIT(0), /* DART Exception */
99 	APIEXCP_ADI0	= CPC925_BIT(1), /* Handshake Error on PI0_ADI */
100 	APIEXCP_ADI1	= CPC925_BIT(2), /* Handshake Error on PI1_ADI */
101 	APIEXCP_STAT	= CPC925_BIT(3), /* Status Exception */
102 	APIEXCP_DERR	= CPC925_BIT(4), /* Data Error Exception */
103 	APIEXCP_ADRS0	= CPC925_BIT(5), /* Addressing Exception on PI0 */
104 	APIEXCP_ADRS1	= CPC925_BIT(6), /* Addressing Exception on PI1 */
105 					 /* BIT(7) Reserved */
106 	APIEXCP_ECC_UE_H = CPC925_BIT(8), /* UECC upper */
107 	APIEXCP_ECC_CE_H = CPC925_BIT(9), /* CECC upper */
108 	APIEXCP_ECC_UE_L = CPC925_BIT(10), /* UECC lower */
109 	APIEXCP_ECC_CE_L = CPC925_BIT(11), /* CECC lower */
110 
111 	CPU_EXCP_DETECTED = (APIEXCP_DART | APIEXCP_ADI0 | APIEXCP_ADI1 |
112 			     APIEXCP_STAT | APIEXCP_DERR | APIEXCP_ADRS0 |
113 			     APIEXCP_ADRS1),
114 	UECC_EXCP_DETECTED = (APIEXCP_ECC_UE_H | APIEXCP_ECC_UE_L),
115 	CECC_EXCP_DETECTED = (APIEXCP_ECC_CE_H | APIEXCP_ECC_CE_L),
116 	ECC_EXCP_DETECTED = (UECC_EXCP_DETECTED | CECC_EXCP_DETECTED),
117 };
118 
119 /************************************************************
120  *	Memory Bus Configuration Register (MBCR)
121 ************************************************************/
122 #define REG_MBCR_OFFSET		0x2190
123 #define MBCR_64BITCFG_SHIFT	23
124 #define MBCR_64BITCFG_MASK	(1UL << MBCR_64BITCFG_SHIFT)
125 #define MBCR_64BITBUS_SHIFT	22
126 #define MBCR_64BITBUS_MASK	(1UL << MBCR_64BITBUS_SHIFT)
127 
128 /************************************************************
129  *	Memory Bank Mode Register (MBMR)
130 ************************************************************/
131 #define REG_MBMR_OFFSET		0x21C0
132 #define MBMR_MODE_MAX_VALUE	0xF
133 #define MBMR_MODE_SHIFT		25
134 #define MBMR_MODE_MASK		(MBMR_MODE_MAX_VALUE << MBMR_MODE_SHIFT)
135 #define MBMR_BBA_SHIFT		24
136 #define MBMR_BBA_MASK		(1UL << MBMR_BBA_SHIFT)
137 
138 /************************************************************
139  *	Memory Bank Boundary Address Register (MBBAR)
140  ************************************************************/
141 #define REG_MBBAR_OFFSET	0x21D0
142 #define MBBAR_BBA_MAX_VALUE	0xFF
143 #define MBBAR_BBA_SHIFT		24
144 #define MBBAR_BBA_MASK		(MBBAR_BBA_MAX_VALUE << MBBAR_BBA_SHIFT)
145 
146 /************************************************************
147  *	Memory Scrub Control Register (MSCR)
148  ************************************************************/
149 #define REG_MSCR_OFFSET		0x2400
150 #define MSCR_SCRUB_MOD_MASK	0xC0000000 /* scrub_mod - bit0:1*/
151 #define MSCR_BACKGR_SCRUB	0x40000000 /* 01 */
152 #define MSCR_SI_SHIFT		16 	/* si - bit8:15*/
153 #define MSCR_SI_MAX_VALUE	0xFF
154 #define MSCR_SI_MASK		(MSCR_SI_MAX_VALUE << MSCR_SI_SHIFT)
155 
156 /************************************************************
157  *	Memory Scrub Range Start Register (MSRSR)
158  ************************************************************/
159 #define REG_MSRSR_OFFSET	0x2410
160 
161 /************************************************************
162  *	Memory Scrub Range End Register (MSRER)
163  ************************************************************/
164 #define REG_MSRER_OFFSET	0x2420
165 
166 /************************************************************
167  *	Memory Scrub Pattern Register (MSPR)
168  ************************************************************/
169 #define REG_MSPR_OFFSET		0x2430
170 
171 /************************************************************
172  *	Memory Check Control Register (MCCR)
173  ************************************************************/
174 #define REG_MCCR_OFFSET		0x2440
175 enum mccr_bits {
176 	MCCR_ECC_EN	= CPC925_BIT(0), /* ECC high and low check */
177 };
178 
179 /************************************************************
180  *	Memory Check Range End Register (MCRER)
181  ************************************************************/
182 #define REG_MCRER_OFFSET	0x2450
183 
184 /************************************************************
185  *	Memory Error Address Register (MEAR)
186  ************************************************************/
187 #define REG_MEAR_OFFSET		0x2460
188 #define MEAR_BCNT_MAX_VALUE	0x3
189 #define MEAR_BCNT_SHIFT		30
190 #define MEAR_BCNT_MASK		(MEAR_BCNT_MAX_VALUE << MEAR_BCNT_SHIFT)
191 #define MEAR_RANK_MAX_VALUE	0x7
192 #define MEAR_RANK_SHIFT		27
193 #define MEAR_RANK_MASK		(MEAR_RANK_MAX_VALUE << MEAR_RANK_SHIFT)
194 #define MEAR_COL_MAX_VALUE	0x7FF
195 #define MEAR_COL_SHIFT		16
196 #define MEAR_COL_MASK		(MEAR_COL_MAX_VALUE << MEAR_COL_SHIFT)
197 #define MEAR_BANK_MAX_VALUE	0x3
198 #define MEAR_BANK_SHIFT		14
199 #define MEAR_BANK_MASK		(MEAR_BANK_MAX_VALUE << MEAR_BANK_SHIFT)
200 #define MEAR_ROW_MASK		0x00003FFF
201 
202 /************************************************************
203  *	Memory Error Syndrome Register (MESR)
204  ************************************************************/
205 #define REG_MESR_OFFSET		0x2470
206 #define MESR_ECC_SYN_H_MASK	0xFF00
207 #define MESR_ECC_SYN_L_MASK	0x00FF
208 
209 /************************************************************
210  *	Memory Mode Control Register (MMCR)
211  ************************************************************/
212 #define REG_MMCR_OFFSET		0x2500
213 enum mmcr_bits {
214 	MMCR_REG_DIMM_MODE = CPC925_BIT(3),
215 };
216 
217 /*
218  * HyperTransport Link Registers
219  */
220 /************************************************************
221  *  Error Handling/Enumeration Scratch Pad Register (ERRCTRL)
222  ************************************************************/
223 #define REG_ERRCTRL_OFFSET	0x70140
224 enum errctrl_bits {			 /* nonfatal interrupts for */
225 	ERRCTRL_SERR_NF	= CPC925_BIT(0), /* system error */
226 	ERRCTRL_CRC_NF	= CPC925_BIT(1), /* CRC error */
227 	ERRCTRL_RSP_NF	= CPC925_BIT(2), /* Response error */
228 	ERRCTRL_EOC_NF	= CPC925_BIT(3), /* End-Of-Chain error */
229 	ERRCTRL_OVF_NF	= CPC925_BIT(4), /* Overflow error */
230 	ERRCTRL_PROT_NF	= CPC925_BIT(5), /* Protocol error */
231 
232 	ERRCTRL_RSP_ERR	= CPC925_BIT(6), /* Response error received */
233 	ERRCTRL_CHN_FAL = CPC925_BIT(7), /* Sync flooding detected */
234 
235 	HT_ERRCTRL_ENABLE = (ERRCTRL_SERR_NF | ERRCTRL_CRC_NF |
236 			     ERRCTRL_RSP_NF | ERRCTRL_EOC_NF |
237 			     ERRCTRL_OVF_NF | ERRCTRL_PROT_NF),
238 	HT_ERRCTRL_DETECTED = (ERRCTRL_RSP_ERR | ERRCTRL_CHN_FAL),
239 };
240 
241 /************************************************************
242  *  Link Configuration and Link Control Register (LINKCTRL)
243  ************************************************************/
244 #define REG_LINKCTRL_OFFSET	0x70110
245 enum linkctrl_bits {
246 	LINKCTRL_CRC_ERR	= (CPC925_BIT(22) | CPC925_BIT(23)),
247 	LINKCTRL_LINK_FAIL	= CPC925_BIT(27),
248 
249 	HT_LINKCTRL_DETECTED	= (LINKCTRL_CRC_ERR | LINKCTRL_LINK_FAIL),
250 };
251 
252 /************************************************************
253  *  Link FreqCap/Error/Freq/Revision ID Register (LINKERR)
254  ************************************************************/
255 #define REG_LINKERR_OFFSET	0x70120
256 enum linkerr_bits {
257 	LINKERR_EOC_ERR		= CPC925_BIT(17), /* End-Of-Chain error */
258 	LINKERR_OVF_ERR		= CPC925_BIT(18), /* Receive Buffer Overflow */
259 	LINKERR_PROT_ERR	= CPC925_BIT(19), /* Protocol error */
260 
261 	HT_LINKERR_DETECTED	= (LINKERR_EOC_ERR | LINKERR_OVF_ERR |
262 				   LINKERR_PROT_ERR),
263 };
264 
265 /************************************************************
266  *	Bridge Control Register (BRGCTRL)
267  ************************************************************/
268 #define REG_BRGCTRL_OFFSET	0x70300
269 enum brgctrl_bits {
270 	BRGCTRL_DETSERR = CPC925_BIT(0), /* SERR on Secondary Bus */
271 	BRGCTRL_SECBUSRESET = CPC925_BIT(9), /* Secondary Bus Reset */
272 };
273 
274 /* Private structure for edac memory controller */
275 struct cpc925_mc_pdata {
276 	void __iomem *vbase;
277 	unsigned long total_mem;
278 	const char *name;
279 	int edac_idx;
280 };
281 
282 /* Private structure for common edac device */
283 struct cpc925_dev_info {
284 	void __iomem *vbase;
285 	struct platform_device *pdev;
286 	char *ctl_name;
287 	int edac_idx;
288 	struct edac_device_ctl_info *edac_dev;
289 	void (*init)(struct cpc925_dev_info *dev_info);
290 	void (*exit)(struct cpc925_dev_info *dev_info);
291 	void (*check)(struct edac_device_ctl_info *edac_dev);
292 };
293 
294 /* Get total memory size from Open Firmware DTB */
295 static void get_total_mem(struct cpc925_mc_pdata *pdata)
296 {
297 	struct device_node *np = NULL;
298 	const unsigned int *reg, *reg_end;
299 	int len, sw, aw;
300 	unsigned long start, size;
301 
302 	np = of_find_node_by_type(NULL, "memory");
303 	if (!np)
304 		return;
305 
306 	aw = of_n_addr_cells(np);
307 	sw = of_n_size_cells(np);
308 	reg = (const unsigned int *)of_get_property(np, "reg", &len);
309 	reg_end = reg + len/4;
310 
311 	pdata->total_mem = 0;
312 	do {
313 		start = of_read_number(reg, aw);
314 		reg += aw;
315 		size = of_read_number(reg, sw);
316 		reg += sw;
317 		debugf1("%s: start 0x%lx, size 0x%lx\n", __func__,
318 			start, size);
319 		pdata->total_mem += size;
320 	} while (reg < reg_end);
321 
322 	of_node_put(np);
323 	debugf0("%s: total_mem 0x%lx\n", __func__, pdata->total_mem);
324 }
325 
326 static void cpc925_init_csrows(struct mem_ctl_info *mci)
327 {
328 	struct cpc925_mc_pdata *pdata = mci->pvt_info;
329 	struct csrow_info *csrow;
330 	int index;
331 	u32 mbmr, mbbar, bba;
332 	unsigned long row_size, last_nr_pages = 0;
333 
334 	get_total_mem(pdata);
335 
336 	for (index = 0; index < mci->nr_csrows; index++) {
337 		mbmr = __raw_readl(pdata->vbase + REG_MBMR_OFFSET +
338 				   0x20 * index);
339 		mbbar = __raw_readl(pdata->vbase + REG_MBBAR_OFFSET +
340 				   0x20 + index);
341 		bba = (((mbmr & MBMR_BBA_MASK) >> MBMR_BBA_SHIFT) << 8) |
342 		       ((mbbar & MBBAR_BBA_MASK) >> MBBAR_BBA_SHIFT);
343 
344 		if (bba == 0)
345 			continue; /* not populated */
346 
347 		csrow = &mci->csrows[index];
348 
349 		row_size = bba * (1UL << 28);	/* 256M */
350 		csrow->first_page = last_nr_pages;
351 		csrow->nr_pages = row_size >> PAGE_SHIFT;
352 		csrow->last_page = csrow->first_page + csrow->nr_pages - 1;
353 		last_nr_pages = csrow->last_page + 1;
354 
355 		csrow->mtype = MEM_RDDR;
356 		csrow->edac_mode = EDAC_SECDED;
357 
358 		switch (csrow->nr_channels) {
359 		case 1: /* Single channel */
360 			csrow->grain = 32; /* four-beat burst of 32 bytes */
361 			break;
362 		case 2: /* Dual channel */
363 		default:
364 			csrow->grain = 64; /* four-beat burst of 64 bytes */
365 			break;
366 		}
367 
368 		switch ((mbmr & MBMR_MODE_MASK) >> MBMR_MODE_SHIFT) {
369 		case 6: /* 0110, no way to differentiate X8 VS X16 */
370 		case 5:	/* 0101 */
371 		case 8: /* 1000 */
372 			csrow->dtype = DEV_X16;
373 			break;
374 		case 7: /* 0111 */
375 		case 9: /* 1001 */
376 			csrow->dtype = DEV_X8;
377 			break;
378 		default:
379 			csrow->dtype = DEV_UNKNOWN;
380 			break;
381 		}
382 	}
383 }
384 
385 /* Enable memory controller ECC detection */
386 static void cpc925_mc_init(struct mem_ctl_info *mci)
387 {
388 	struct cpc925_mc_pdata *pdata = mci->pvt_info;
389 	u32 apimask;
390 	u32 mccr;
391 
392 	/* Enable various ECC error exceptions */
393 	apimask = __raw_readl(pdata->vbase + REG_APIMASK_OFFSET);
394 	if ((apimask & ECC_MASK_ENABLE) == 0) {
395 		apimask |= ECC_MASK_ENABLE;
396 		__raw_writel(apimask, pdata->vbase + REG_APIMASK_OFFSET);
397 	}
398 
399 	/* Enable ECC detection */
400 	mccr = __raw_readl(pdata->vbase + REG_MCCR_OFFSET);
401 	if ((mccr & MCCR_ECC_EN) == 0) {
402 		mccr |= MCCR_ECC_EN;
403 		__raw_writel(mccr, pdata->vbase + REG_MCCR_OFFSET);
404 	}
405 }
406 
407 /* Disable memory controller ECC detection */
408 static void cpc925_mc_exit(struct mem_ctl_info *mci)
409 {
410 	/*
411 	 * WARNING:
412 	 * We are supposed to clear the ECC error detection bits,
413 	 * and it will be no problem to do so. However, once they
414 	 * are cleared here if we want to re-install CPC925 EDAC
415 	 * module later, setting them up in cpc925_mc_init() will
416 	 * trigger machine check exception.
417 	 * Also, it's ok to leave ECC error detection bits enabled,
418 	 * since they are reset to 1 by default or by boot loader.
419 	 */
420 
421 	return;
422 }
423 
424 /*
425  * Revert DDR column/row/bank addresses into page frame number and
426  * offset in page.
427  *
428  * Suppose memory mode is 0x0111(128-bit mode, identical DIMM pairs),
429  * physical address(PA) bits to column address(CA) bits mappings are:
430  * CA	0   1   2   3   4   5   6   7   8   9   10
431  * PA	59  58  57  56  55  54  53  52  51  50  49
432  *
433  * physical address(PA) bits to bank address(BA) bits mappings are:
434  * BA	0   1
435  * PA	43  44
436  *
437  * physical address(PA) bits to row address(RA) bits mappings are:
438  * RA	0   1   2   3   4   5   6   7   8   9   10   11   12
439  * PA	36  35  34  48  47  46  45  40  41  42  39   38   37
440  */
441 static void cpc925_mc_get_pfn(struct mem_ctl_info *mci, u32 mear,
442 		unsigned long *pfn, unsigned long *offset, int *csrow)
443 {
444 	u32 bcnt, rank, col, bank, row;
445 	u32 c;
446 	unsigned long pa;
447 	int i;
448 
449 	bcnt = (mear & MEAR_BCNT_MASK) >> MEAR_BCNT_SHIFT;
450 	rank = (mear & MEAR_RANK_MASK) >> MEAR_RANK_SHIFT;
451 	col = (mear & MEAR_COL_MASK) >> MEAR_COL_SHIFT;
452 	bank = (mear & MEAR_BANK_MASK) >> MEAR_BANK_SHIFT;
453 	row = mear & MEAR_ROW_MASK;
454 
455 	*csrow = rank;
456 
457 #ifdef CONFIG_EDAC_DEBUG
458 	if (mci->csrows[rank].first_page == 0) {
459 		cpc925_mc_printk(mci, KERN_ERR, "ECC occurs in a "
460 			"non-populated csrow, broken hardware?\n");
461 		return;
462 	}
463 #endif
464 
465 	/* Revert csrow number */
466 	pa = mci->csrows[rank].first_page << PAGE_SHIFT;
467 
468 	/* Revert column address */
469 	col += bcnt;
470 	for (i = 0; i < 11; i++) {
471 		c = col & 0x1;
472 		col >>= 1;
473 		pa |= c << (14 - i);
474 	}
475 
476 	/* Revert bank address */
477 	pa |= bank << 19;
478 
479 	/* Revert row address, in 4 steps */
480 	for (i = 0; i < 3; i++) {
481 		c = row & 0x1;
482 		row >>= 1;
483 		pa |= c << (26 - i);
484 	}
485 
486 	for (i = 0; i < 3; i++) {
487 		c = row & 0x1;
488 		row >>= 1;
489 		pa |= c << (21 + i);
490 	}
491 
492 	for (i = 0; i < 4; i++) {
493 		c = row & 0x1;
494 		row >>= 1;
495 		pa |= c << (18 - i);
496 	}
497 
498 	for (i = 0; i < 3; i++) {
499 		c = row & 0x1;
500 		row >>= 1;
501 		pa |= c << (29 - i);
502 	}
503 
504 	*offset = pa & (PAGE_SIZE - 1);
505 	*pfn = pa >> PAGE_SHIFT;
506 
507 	debugf0("%s: ECC physical address 0x%lx\n", __func__, pa);
508 }
509 
510 static int cpc925_mc_find_channel(struct mem_ctl_info *mci, u16 syndrome)
511 {
512 	if ((syndrome & MESR_ECC_SYN_H_MASK) == 0)
513 		return 0;
514 
515 	if ((syndrome & MESR_ECC_SYN_L_MASK) == 0)
516 		return 1;
517 
518 	cpc925_mc_printk(mci, KERN_INFO, "Unexpected syndrome value: 0x%x\n",
519 			 syndrome);
520 	return 1;
521 }
522 
523 /* Check memory controller registers for ECC errors */
524 static void cpc925_mc_check(struct mem_ctl_info *mci)
525 {
526 	struct cpc925_mc_pdata *pdata = mci->pvt_info;
527 	u32 apiexcp;
528 	u32 mear;
529 	u32 mesr;
530 	u16 syndrome;
531 	unsigned long pfn = 0, offset = 0;
532 	int csrow = 0, channel = 0;
533 
534 	/* APIEXCP is cleared when read */
535 	apiexcp = __raw_readl(pdata->vbase + REG_APIEXCP_OFFSET);
536 	if ((apiexcp & ECC_EXCP_DETECTED) == 0)
537 		return;
538 
539 	mesr = __raw_readl(pdata->vbase + REG_MESR_OFFSET);
540 	syndrome = mesr | (MESR_ECC_SYN_H_MASK | MESR_ECC_SYN_L_MASK);
541 
542 	mear = __raw_readl(pdata->vbase + REG_MEAR_OFFSET);
543 
544 	/* Revert column/row addresses into page frame number, etc */
545 	cpc925_mc_get_pfn(mci, mear, &pfn, &offset, &csrow);
546 
547 	if (apiexcp & CECC_EXCP_DETECTED) {
548 		cpc925_mc_printk(mci, KERN_INFO, "DRAM CECC Fault\n");
549 		channel = cpc925_mc_find_channel(mci, syndrome);
550 		edac_mc_handle_ce(mci, pfn, offset, syndrome,
551 				  csrow, channel, mci->ctl_name);
552 	}
553 
554 	if (apiexcp & UECC_EXCP_DETECTED) {
555 		cpc925_mc_printk(mci, KERN_INFO, "DRAM UECC Fault\n");
556 		edac_mc_handle_ue(mci, pfn, offset, csrow, mci->ctl_name);
557 	}
558 
559 	cpc925_mc_printk(mci, KERN_INFO, "Dump registers:\n");
560 	cpc925_mc_printk(mci, KERN_INFO, "APIMASK		0x%08x\n",
561 		__raw_readl(pdata->vbase + REG_APIMASK_OFFSET));
562 	cpc925_mc_printk(mci, KERN_INFO, "APIEXCP		0x%08x\n",
563 		apiexcp);
564 	cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Ctrl	0x%08x\n",
565 		__raw_readl(pdata->vbase + REG_MSCR_OFFSET));
566 	cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Rge Start	0x%08x\n",
567 		__raw_readl(pdata->vbase + REG_MSRSR_OFFSET));
568 	cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Rge End	0x%08x\n",
569 		__raw_readl(pdata->vbase + REG_MSRER_OFFSET));
570 	cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Pattern	0x%08x\n",
571 		__raw_readl(pdata->vbase + REG_MSPR_OFFSET));
572 	cpc925_mc_printk(mci, KERN_INFO, "Mem Chk Ctrl		0x%08x\n",
573 		__raw_readl(pdata->vbase + REG_MCCR_OFFSET));
574 	cpc925_mc_printk(mci, KERN_INFO, "Mem Chk Rge End	0x%08x\n",
575 		__raw_readl(pdata->vbase + REG_MCRER_OFFSET));
576 	cpc925_mc_printk(mci, KERN_INFO, "Mem Err Address	0x%08x\n",
577 		mesr);
578 	cpc925_mc_printk(mci, KERN_INFO, "Mem Err Syndrome	0x%08x\n",
579 		syndrome);
580 }
581 
582 /******************** CPU err device********************************/
583 /* Enable CPU Errors detection */
584 static void cpc925_cpu_init(struct cpc925_dev_info *dev_info)
585 {
586 	u32 apimask;
587 
588 	apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
589 	if ((apimask & CPU_MASK_ENABLE) == 0) {
590 		apimask |= CPU_MASK_ENABLE;
591 		__raw_writel(apimask, dev_info->vbase + REG_APIMASK_OFFSET);
592 	}
593 }
594 
595 /* Disable CPU Errors detection */
596 static void cpc925_cpu_exit(struct cpc925_dev_info *dev_info)
597 {
598 	/*
599 	 * WARNING:
600 	 * We are supposed to clear the CPU error detection bits,
601 	 * and it will be no problem to do so. However, once they
602 	 * are cleared here if we want to re-install CPC925 EDAC
603 	 * module later, setting them up in cpc925_cpu_init() will
604 	 * trigger machine check exception.
605 	 * Also, it's ok to leave CPU error detection bits enabled,
606 	 * since they are reset to 1 by default.
607 	 */
608 
609 	return;
610 }
611 
612 /* Check for CPU Errors */
613 static void cpc925_cpu_check(struct edac_device_ctl_info *edac_dev)
614 {
615 	struct cpc925_dev_info *dev_info = edac_dev->pvt_info;
616 	u32 apiexcp;
617 	u32 apimask;
618 
619 	/* APIEXCP is cleared when read */
620 	apiexcp = __raw_readl(dev_info->vbase + REG_APIEXCP_OFFSET);
621 	if ((apiexcp & CPU_EXCP_DETECTED) == 0)
622 		return;
623 
624 	apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
625 	cpc925_printk(KERN_INFO, "Processor Interface Fault\n"
626 				 "Processor Interface register dump:\n");
627 	cpc925_printk(KERN_INFO, "APIMASK		0x%08x\n", apimask);
628 	cpc925_printk(KERN_INFO, "APIEXCP		0x%08x\n", apiexcp);
629 
630 	edac_device_handle_ue(edac_dev, 0, 0, edac_dev->ctl_name);
631 }
632 
633 /******************** HT Link err device****************************/
634 /* Enable HyperTransport Link Error detection */
635 static void cpc925_htlink_init(struct cpc925_dev_info *dev_info)
636 {
637 	u32 ht_errctrl;
638 
639 	ht_errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
640 	if ((ht_errctrl & HT_ERRCTRL_ENABLE) == 0) {
641 		ht_errctrl |= HT_ERRCTRL_ENABLE;
642 		__raw_writel(ht_errctrl, dev_info->vbase + REG_ERRCTRL_OFFSET);
643 	}
644 }
645 
646 /* Disable HyperTransport Link Error detection */
647 static void cpc925_htlink_exit(struct cpc925_dev_info *dev_info)
648 {
649 	u32 ht_errctrl;
650 
651 	ht_errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
652 	ht_errctrl &= ~HT_ERRCTRL_ENABLE;
653 	__raw_writel(ht_errctrl, dev_info->vbase + REG_ERRCTRL_OFFSET);
654 }
655 
656 /* Check for HyperTransport Link errors */
657 static void cpc925_htlink_check(struct edac_device_ctl_info *edac_dev)
658 {
659 	struct cpc925_dev_info *dev_info = edac_dev->pvt_info;
660 	u32 brgctrl = __raw_readl(dev_info->vbase + REG_BRGCTRL_OFFSET);
661 	u32 linkctrl = __raw_readl(dev_info->vbase + REG_LINKCTRL_OFFSET);
662 	u32 errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
663 	u32 linkerr = __raw_readl(dev_info->vbase + REG_LINKERR_OFFSET);
664 
665 	if (!((brgctrl & BRGCTRL_DETSERR) ||
666 	      (linkctrl & HT_LINKCTRL_DETECTED) ||
667 	      (errctrl & HT_ERRCTRL_DETECTED) ||
668 	      (linkerr & HT_LINKERR_DETECTED)))
669 		return;
670 
671 	cpc925_printk(KERN_INFO, "HT Link Fault\n"
672 				 "HT register dump:\n");
673 	cpc925_printk(KERN_INFO, "Bridge Ctrl			0x%08x\n",
674 		      brgctrl);
675 	cpc925_printk(KERN_INFO, "Link Config Ctrl		0x%08x\n",
676 		      linkctrl);
677 	cpc925_printk(KERN_INFO, "Error Enum and Ctrl		0x%08x\n",
678 		      errctrl);
679 	cpc925_printk(KERN_INFO, "Link Error			0x%08x\n",
680 		      linkerr);
681 
682 	/* Clear by write 1 */
683 	if (brgctrl & BRGCTRL_DETSERR)
684 		__raw_writel(BRGCTRL_DETSERR,
685 				dev_info->vbase + REG_BRGCTRL_OFFSET);
686 
687 	if (linkctrl & HT_LINKCTRL_DETECTED)
688 		__raw_writel(HT_LINKCTRL_DETECTED,
689 				dev_info->vbase + REG_LINKCTRL_OFFSET);
690 
691 	/* Initiate Secondary Bus Reset to clear the chain failure */
692 	if (errctrl & ERRCTRL_CHN_FAL)
693 		__raw_writel(BRGCTRL_SECBUSRESET,
694 				dev_info->vbase + REG_BRGCTRL_OFFSET);
695 
696 	if (errctrl & ERRCTRL_RSP_ERR)
697 		__raw_writel(ERRCTRL_RSP_ERR,
698 				dev_info->vbase + REG_ERRCTRL_OFFSET);
699 
700 	if (linkerr & HT_LINKERR_DETECTED)
701 		__raw_writel(HT_LINKERR_DETECTED,
702 				dev_info->vbase + REG_LINKERR_OFFSET);
703 
704 	edac_device_handle_ce(edac_dev, 0, 0, edac_dev->ctl_name);
705 }
706 
707 static struct cpc925_dev_info cpc925_devs[] = {
708 	{
709 	.ctl_name = CPC925_CPU_ERR_DEV,
710 	.init = cpc925_cpu_init,
711 	.exit = cpc925_cpu_exit,
712 	.check = cpc925_cpu_check,
713 	},
714 	{
715 	.ctl_name = CPC925_HT_LINK_DEV,
716 	.init = cpc925_htlink_init,
717 	.exit = cpc925_htlink_exit,
718 	.check = cpc925_htlink_check,
719 	},
720 	{0}, /* Terminated by NULL */
721 };
722 
723 /*
724  * Add CPU Err detection and HyperTransport Link Err detection
725  * as common "edac_device", they have no corresponding device
726  * nodes in the Open Firmware DTB and we have to add platform
727  * devices for them. Also, they will share the MMIO with that
728  * of memory controller.
729  */
730 static void cpc925_add_edac_devices(void __iomem *vbase)
731 {
732 	struct cpc925_dev_info *dev_info;
733 
734 	if (!vbase) {
735 		cpc925_printk(KERN_ERR, "MMIO not established yet\n");
736 		return;
737 	}
738 
739 	for (dev_info = &cpc925_devs[0]; dev_info->init; dev_info++) {
740 		dev_info->vbase = vbase;
741 		dev_info->pdev = platform_device_register_simple(
742 					dev_info->ctl_name, 0, NULL, 0);
743 		if (IS_ERR(dev_info->pdev)) {
744 			cpc925_printk(KERN_ERR,
745 				"Can't register platform device for %s\n",
746 				dev_info->ctl_name);
747 			continue;
748 		}
749 
750 		/*
751 		 * Don't have to allocate private structure but
752 		 * make use of cpc925_devs[] instead.
753 		 */
754 		dev_info->edac_idx = edac_device_alloc_index();
755 		dev_info->edac_dev =
756 			edac_device_alloc_ctl_info(0, dev_info->ctl_name,
757 				1, NULL, 0, 0, NULL, 0, dev_info->edac_idx);
758 		if (!dev_info->edac_dev) {
759 			cpc925_printk(KERN_ERR, "No memory for edac device\n");
760 			goto err1;
761 		}
762 
763 		dev_info->edac_dev->pvt_info = dev_info;
764 		dev_info->edac_dev->dev = &dev_info->pdev->dev;
765 		dev_info->edac_dev->ctl_name = dev_info->ctl_name;
766 		dev_info->edac_dev->mod_name = CPC925_EDAC_MOD_STR;
767 		dev_info->edac_dev->dev_name = dev_name(&dev_info->pdev->dev);
768 
769 		if (edac_op_state == EDAC_OPSTATE_POLL)
770 			dev_info->edac_dev->edac_check = dev_info->check;
771 
772 		if (dev_info->init)
773 			dev_info->init(dev_info);
774 
775 		if (edac_device_add_device(dev_info->edac_dev) > 0) {
776 			cpc925_printk(KERN_ERR,
777 				"Unable to add edac device for %s\n",
778 				dev_info->ctl_name);
779 			goto err2;
780 		}
781 
782 		debugf0("%s: Successfully added edac device for %s\n",
783 			__func__, dev_info->ctl_name);
784 
785 		continue;
786 
787 err2:
788 		if (dev_info->exit)
789 			dev_info->exit(dev_info);
790 		edac_device_free_ctl_info(dev_info->edac_dev);
791 err1:
792 		platform_device_unregister(dev_info->pdev);
793 	}
794 }
795 
796 /*
797  * Delete the common "edac_device" for CPU Err Detection
798  * and HyperTransport Link Err Detection
799  */
800 static void cpc925_del_edac_devices(void)
801 {
802 	struct cpc925_dev_info *dev_info;
803 
804 	for (dev_info = &cpc925_devs[0]; dev_info->init; dev_info++) {
805 		if (dev_info->edac_dev) {
806 			edac_device_del_device(dev_info->edac_dev->dev);
807 			edac_device_free_ctl_info(dev_info->edac_dev);
808 			platform_device_unregister(dev_info->pdev);
809 		}
810 
811 		if (dev_info->exit)
812 			dev_info->exit(dev_info);
813 
814 		debugf0("%s: Successfully deleted edac device for %s\n",
815 			__func__, dev_info->ctl_name);
816 	}
817 }
818 
819 /* Convert current back-ground scrub rate into byte/sec bandwith */
820 static int cpc925_get_sdram_scrub_rate(struct mem_ctl_info *mci, u32 *bw)
821 {
822 	struct cpc925_mc_pdata *pdata = mci->pvt_info;
823 	u32 mscr;
824 	u8 si;
825 
826 	mscr = __raw_readl(pdata->vbase + REG_MSCR_OFFSET);
827 	si = (mscr & MSCR_SI_MASK) >> MSCR_SI_SHIFT;
828 
829 	debugf0("%s, Mem Scrub Ctrl Register 0x%x\n", __func__, mscr);
830 
831 	if (((mscr & MSCR_SCRUB_MOD_MASK) != MSCR_BACKGR_SCRUB) ||
832 	    (si == 0)) {
833 		cpc925_mc_printk(mci, KERN_INFO, "Scrub mode not enabled\n");
834 		*bw = 0;
835 	} else
836 		*bw = CPC925_SCRUB_BLOCK_SIZE * 0xFA67 / si;
837 
838 	return 0;
839 }
840 
841 /* Return 0 for single channel; 1 for dual channel */
842 static int cpc925_mc_get_channels(void __iomem *vbase)
843 {
844 	int dual = 0;
845 	u32 mbcr;
846 
847 	mbcr = __raw_readl(vbase + REG_MBCR_OFFSET);
848 
849 	/*
850 	 * Dual channel only when 128-bit wide physical bus
851 	 * and 128-bit configuration.
852 	 */
853 	if (((mbcr & MBCR_64BITCFG_MASK) == 0) &&
854 	    ((mbcr & MBCR_64BITBUS_MASK) == 0))
855 		dual = 1;
856 
857 	debugf0("%s: %s channel\n", __func__,
858 		(dual > 0) ? "Dual" : "Single");
859 
860 	return dual;
861 }
862 
863 static int __devinit cpc925_probe(struct platform_device *pdev)
864 {
865 	static int edac_mc_idx;
866 	struct mem_ctl_info *mci;
867 	void __iomem *vbase;
868 	struct cpc925_mc_pdata *pdata;
869 	struct resource *r;
870 	int res = 0, nr_channels;
871 
872 	debugf0("%s: %s platform device found!\n", __func__, pdev->name);
873 
874 	if (!devres_open_group(&pdev->dev, cpc925_probe, GFP_KERNEL)) {
875 		res = -ENOMEM;
876 		goto out;
877 	}
878 
879 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
880 	if (!r) {
881 		cpc925_printk(KERN_ERR, "Unable to get resource\n");
882 		res = -ENOENT;
883 		goto err1;
884 	}
885 
886 	if (!devm_request_mem_region(&pdev->dev,
887 				     r->start,
888 				     r->end - r->start + 1,
889 				     pdev->name)) {
890 		cpc925_printk(KERN_ERR, "Unable to request mem region\n");
891 		res = -EBUSY;
892 		goto err1;
893 	}
894 
895 	vbase = devm_ioremap(&pdev->dev, r->start, r->end - r->start + 1);
896 	if (!vbase) {
897 		cpc925_printk(KERN_ERR, "Unable to ioremap device\n");
898 		res = -ENOMEM;
899 		goto err2;
900 	}
901 
902 	nr_channels = cpc925_mc_get_channels(vbase);
903 	mci = edac_mc_alloc(sizeof(struct cpc925_mc_pdata),
904 			CPC925_NR_CSROWS, nr_channels + 1, edac_mc_idx);
905 	if (!mci) {
906 		cpc925_printk(KERN_ERR, "No memory for mem_ctl_info\n");
907 		res = -ENOMEM;
908 		goto err2;
909 	}
910 
911 	pdata = mci->pvt_info;
912 	pdata->vbase = vbase;
913 	pdata->edac_idx = edac_mc_idx++;
914 	pdata->name = pdev->name;
915 
916 	mci->dev = &pdev->dev;
917 	platform_set_drvdata(pdev, mci);
918 	mci->dev_name = dev_name(&pdev->dev);
919 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
920 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
921 	mci->edac_cap = EDAC_FLAG_SECDED;
922 	mci->mod_name = CPC925_EDAC_MOD_STR;
923 	mci->mod_ver = CPC925_EDAC_REVISION;
924 	mci->ctl_name = pdev->name;
925 
926 	if (edac_op_state == EDAC_OPSTATE_POLL)
927 		mci->edac_check = cpc925_mc_check;
928 
929 	mci->ctl_page_to_phys = NULL;
930 	mci->scrub_mode = SCRUB_SW_SRC;
931 	mci->set_sdram_scrub_rate = NULL;
932 	mci->get_sdram_scrub_rate = cpc925_get_sdram_scrub_rate;
933 
934 	cpc925_init_csrows(mci);
935 
936 	/* Setup memory controller registers */
937 	cpc925_mc_init(mci);
938 
939 	if (edac_mc_add_mc(mci) > 0) {
940 		cpc925_mc_printk(mci, KERN_ERR, "Failed edac_mc_add_mc()\n");
941 		goto err3;
942 	}
943 
944 	cpc925_add_edac_devices(vbase);
945 
946 	/* get this far and it's successful */
947 	debugf0("%s: success\n", __func__);
948 
949 	res = 0;
950 	goto out;
951 
952 err3:
953 	cpc925_mc_exit(mci);
954 	edac_mc_free(mci);
955 err2:
956 	devm_release_mem_region(&pdev->dev, r->start, r->end-r->start+1);
957 err1:
958 	devres_release_group(&pdev->dev, cpc925_probe);
959 out:
960 	return res;
961 }
962 
963 static int cpc925_remove(struct platform_device *pdev)
964 {
965 	struct mem_ctl_info *mci = platform_get_drvdata(pdev);
966 
967 	/*
968 	 * Delete common edac devices before edac mc, because
969 	 * the former share the MMIO of the latter.
970 	 */
971 	cpc925_del_edac_devices();
972 	cpc925_mc_exit(mci);
973 
974 	edac_mc_del_mc(&pdev->dev);
975 	edac_mc_free(mci);
976 
977 	return 0;
978 }
979 
980 static struct platform_driver cpc925_edac_driver = {
981 	.probe = cpc925_probe,
982 	.remove = cpc925_remove,
983 	.driver = {
984 		   .name = "cpc925_edac",
985 	}
986 };
987 
988 static int __init cpc925_edac_init(void)
989 {
990 	int ret = 0;
991 
992 	printk(KERN_INFO "IBM CPC925 EDAC driver " CPC925_EDAC_REVISION "\n");
993 	printk(KERN_INFO "\t(c) 2008 Wind River Systems, Inc\n");
994 
995 	/* Only support POLL mode so far */
996 	edac_op_state = EDAC_OPSTATE_POLL;
997 
998 	ret = platform_driver_register(&cpc925_edac_driver);
999 	if (ret) {
1000 		printk(KERN_WARNING "Failed to register %s\n",
1001 			CPC925_EDAC_MOD_STR);
1002 	}
1003 
1004 	return ret;
1005 }
1006 
1007 static void __exit cpc925_edac_exit(void)
1008 {
1009 	platform_driver_unregister(&cpc925_edac_driver);
1010 }
1011 
1012 module_init(cpc925_edac_init);
1013 module_exit(cpc925_edac_exit);
1014 
1015 MODULE_LICENSE("GPL");
1016 MODULE_AUTHOR("Cao Qingtao <qingtao.cao@windriver.com>");
1017 MODULE_DESCRIPTION("IBM CPC925 Bridge and MC EDAC kernel module");
1018