xref: /openbmc/linux/drivers/edac/igen6_edac.c (revision f7af616c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Intel client SoC with integrated memory controller using IBECC
4  *
5  * Copyright (C) 2020 Intel Corporation
6  *
7  * The In-Band ECC (IBECC) IP provides ECC protection to all or specific
8  * regions of the physical memory space. It's used for memory controllers
9  * that don't support the out-of-band ECC which often needs an additional
10  * storage device to each channel for storing ECC data.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/pci.h>
16 #include <linux/slab.h>
17 #include <linux/irq_work.h>
18 #include <linux/llist.h>
19 #include <linux/genalloc.h>
20 #include <linux/edac.h>
21 #include <linux/bits.h>
22 #include <linux/io.h>
23 #include <asm/mach_traps.h>
24 #include <asm/nmi.h>
25 
26 #include "edac_mc.h"
27 #include "edac_module.h"
28 
29 #define IGEN6_REVISION	"v2.4"
30 
31 #define EDAC_MOD_STR	"igen6_edac"
32 #define IGEN6_NMI_NAME	"igen6_ibecc"
33 
34 /* Debug macros */
35 #define igen6_printk(level, fmt, arg...)		\
36 	edac_printk(level, "igen6", fmt, ##arg)
37 
38 #define igen6_mc_printk(mci, level, fmt, arg...)	\
39 	edac_mc_chipset_printk(mci, level, "igen6", fmt, ##arg)
40 
41 #define GET_BITFIELD(v, lo, hi) (((v) & GENMASK_ULL(hi, lo)) >> (lo))
42 
43 #define NUM_IMC				1 /* Max memory controllers */
44 #define NUM_CHANNELS			2 /* Max channels */
45 #define NUM_DIMMS			2 /* Max DIMMs per channel */
46 
47 #define _4GB				BIT_ULL(32)
48 
49 /* Size of physical memory */
50 #define TOM_OFFSET			0xa0
51 /* Top of low usable DRAM */
52 #define TOLUD_OFFSET			0xbc
53 /* Capability register C */
54 #define CAPID_C_OFFSET			0xec
55 #define CAPID_C_IBECC			BIT(15)
56 
57 /* Error Status */
58 #define ERRSTS_OFFSET			0xc8
59 #define ERRSTS_CE			BIT_ULL(6)
60 #define ERRSTS_UE			BIT_ULL(7)
61 
62 /* Error Command */
63 #define ERRCMD_OFFSET			0xca
64 #define ERRCMD_CE			BIT_ULL(6)
65 #define ERRCMD_UE			BIT_ULL(7)
66 
67 /* IBECC MMIO base address */
68 #define IBECC_BASE			(res_cfg->ibecc_base)
69 #define IBECC_ACTIVATE_OFFSET		IBECC_BASE
70 #define IBECC_ACTIVATE_EN		BIT(0)
71 
72 /* IBECC error log */
73 #define ECC_ERROR_LOG_OFFSET		(IBECC_BASE + 0x170)
74 #define ECC_ERROR_LOG_CE		BIT_ULL(62)
75 #define ECC_ERROR_LOG_UE		BIT_ULL(63)
76 #define ECC_ERROR_LOG_ADDR_SHIFT	5
77 #define ECC_ERROR_LOG_ADDR(v)		GET_BITFIELD(v, 5, 38)
78 #define ECC_ERROR_LOG_SYND(v)		GET_BITFIELD(v, 46, 61)
79 
80 /* Host MMIO base address */
81 #define MCHBAR_OFFSET			0x48
82 #define MCHBAR_EN			BIT_ULL(0)
83 #define MCHBAR_BASE(v)			(GET_BITFIELD(v, 16, 38) << 16)
84 #define MCHBAR_SIZE			0x10000
85 
86 /* Parameters for the channel decode stage */
87 #define MAD_INTER_CHANNEL_OFFSET	0x5000
88 #define MAD_INTER_CHANNEL_DDR_TYPE(v)	GET_BITFIELD(v, 0, 2)
89 #define MAD_INTER_CHANNEL_ECHM(v)	GET_BITFIELD(v, 3, 3)
90 #define MAD_INTER_CHANNEL_CH_L_MAP(v)	GET_BITFIELD(v, 4, 4)
91 #define MAD_INTER_CHANNEL_CH_S_SIZE(v)	((u64)GET_BITFIELD(v, 12, 19) << 29)
92 
93 /* Parameters for DRAM decode stage */
94 #define MAD_INTRA_CH0_OFFSET		0x5004
95 #define MAD_INTRA_CH_DIMM_L_MAP(v)	GET_BITFIELD(v, 0, 0)
96 
97 /* DIMM characteristics */
98 #define MAD_DIMM_CH0_OFFSET		0x500c
99 #define MAD_DIMM_CH_DIMM_L_SIZE(v)	((u64)GET_BITFIELD(v, 0, 6) << 29)
100 #define MAD_DIMM_CH_DLW(v)		GET_BITFIELD(v, 7, 8)
101 #define MAD_DIMM_CH_DIMM_S_SIZE(v)	((u64)GET_BITFIELD(v, 16, 22) << 29)
102 #define MAD_DIMM_CH_DSW(v)		GET_BITFIELD(v, 24, 25)
103 
104 /* Hash for channel selection */
105 #define CHANNEL_HASH_OFFSET		0X5024
106 /* Hash for enhanced channel selection */
107 #define CHANNEL_EHASH_OFFSET		0X5028
108 #define CHANNEL_HASH_MASK(v)		(GET_BITFIELD(v, 6, 19) << 6)
109 #define CHANNEL_HASH_LSB_MASK_BIT(v)	GET_BITFIELD(v, 24, 26)
110 #define CHANNEL_HASH_MODE(v)		GET_BITFIELD(v, 28, 28)
111 
112 static struct res_config {
113 	int num_imc;
114 	u32 ibecc_base;
115 	bool (*ibecc_available)(struct pci_dev *pdev);
116 	/* Convert error address logged in IBECC to system physical address */
117 	u64 (*err_addr_to_sys_addr)(u64 eaddr);
118 	/* Convert error address logged in IBECC to integrated memory controller address */
119 	u64 (*err_addr_to_imc_addr)(u64 eaddr);
120 } *res_cfg;
121 
122 struct igen6_imc {
123 	int mc;
124 	struct mem_ctl_info *mci;
125 	struct pci_dev *pdev;
126 	struct device dev;
127 	void __iomem *window;
128 	u64 ch_s_size;
129 	int ch_l_map;
130 	u64 dimm_s_size[NUM_CHANNELS];
131 	u64 dimm_l_size[NUM_CHANNELS];
132 	int dimm_l_map[NUM_CHANNELS];
133 };
134 
135 static struct igen6_pvt {
136 	struct igen6_imc imc[NUM_IMC];
137 } *igen6_pvt;
138 
139 /* The top of low usable DRAM */
140 static u32 igen6_tolud;
141 /* The size of physical memory */
142 static u64 igen6_tom;
143 
144 struct decoded_addr {
145 	int mc;
146 	u64 imc_addr;
147 	u64 sys_addr;
148 	int channel_idx;
149 	u64 channel_addr;
150 	int sub_channel_idx;
151 	u64 sub_channel_addr;
152 };
153 
154 struct ecclog_node {
155 	struct llist_node llnode;
156 	int mc;
157 	u64 ecclog;
158 };
159 
160 /*
161  * In the NMI handler, the driver uses the lock-less memory allocator
162  * to allocate memory to store the IBECC error logs and links the logs
163  * to the lock-less list. Delay printk() and the work of error reporting
164  * to EDAC core in a worker.
165  */
166 #define ECCLOG_POOL_SIZE	PAGE_SIZE
167 static LLIST_HEAD(ecclog_llist);
168 static struct gen_pool *ecclog_pool;
169 static char ecclog_buf[ECCLOG_POOL_SIZE];
170 static struct irq_work ecclog_irq_work;
171 static struct work_struct ecclog_work;
172 
173 /* Compute die IDs for Elkhart Lake with IBECC */
174 #define DID_EHL_SKU5	0x4514
175 #define DID_EHL_SKU6	0x4528
176 #define DID_EHL_SKU7	0x452a
177 #define DID_EHL_SKU8	0x4516
178 #define DID_EHL_SKU9	0x452c
179 #define DID_EHL_SKU10	0x452e
180 #define DID_EHL_SKU11	0x4532
181 #define DID_EHL_SKU12	0x4518
182 #define DID_EHL_SKU13	0x451a
183 #define DID_EHL_SKU14	0x4534
184 #define DID_EHL_SKU15	0x4536
185 
186 static bool ehl_ibecc_available(struct pci_dev *pdev)
187 {
188 	u32 v;
189 
190 	if (pci_read_config_dword(pdev, CAPID_C_OFFSET, &v))
191 		return false;
192 
193 	return !!(CAPID_C_IBECC & v);
194 }
195 
196 static u64 ehl_err_addr_to_sys_addr(u64 eaddr)
197 {
198 	return eaddr;
199 }
200 
201 static u64 ehl_err_addr_to_imc_addr(u64 eaddr)
202 {
203 	if (eaddr < igen6_tolud)
204 		return eaddr;
205 
206 	if (igen6_tom <= _4GB)
207 		return eaddr + igen6_tolud - _4GB;
208 
209 	if (eaddr < _4GB)
210 		return eaddr + igen6_tolud - igen6_tom;
211 
212 	return eaddr;
213 }
214 
215 static struct res_config ehl_cfg = {
216 	.num_imc	 = 1,
217 	.ibecc_base	 = 0xdc00,
218 	.ibecc_available = ehl_ibecc_available,
219 	.err_addr_to_sys_addr  = ehl_err_addr_to_sys_addr,
220 	.err_addr_to_imc_addr  = ehl_err_addr_to_imc_addr,
221 };
222 
223 static const struct pci_device_id igen6_pci_tbl[] = {
224 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU5), (kernel_ulong_t)&ehl_cfg },
225 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU6), (kernel_ulong_t)&ehl_cfg },
226 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU7), (kernel_ulong_t)&ehl_cfg },
227 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU8), (kernel_ulong_t)&ehl_cfg },
228 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU9), (kernel_ulong_t)&ehl_cfg },
229 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU10), (kernel_ulong_t)&ehl_cfg },
230 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU11), (kernel_ulong_t)&ehl_cfg },
231 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU12), (kernel_ulong_t)&ehl_cfg },
232 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU13), (kernel_ulong_t)&ehl_cfg },
233 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU14), (kernel_ulong_t)&ehl_cfg },
234 	{ PCI_VDEVICE(INTEL, DID_EHL_SKU15), (kernel_ulong_t)&ehl_cfg },
235 	{ },
236 };
237 MODULE_DEVICE_TABLE(pci, igen6_pci_tbl);
238 
239 static enum dev_type get_width(int dimm_l, u32 mad_dimm)
240 {
241 	u32 w = dimm_l ? MAD_DIMM_CH_DLW(mad_dimm) :
242 			 MAD_DIMM_CH_DSW(mad_dimm);
243 
244 	switch (w) {
245 	case 0:
246 		return DEV_X8;
247 	case 1:
248 		return DEV_X16;
249 	case 2:
250 		return DEV_X32;
251 	default:
252 		return DEV_UNKNOWN;
253 	}
254 }
255 
256 static enum mem_type get_memory_type(u32 mad_inter)
257 {
258 	u32 t = MAD_INTER_CHANNEL_DDR_TYPE(mad_inter);
259 
260 	switch (t) {
261 	case 0:
262 		return MEM_DDR4;
263 	case 1:
264 		return MEM_DDR3;
265 	case 2:
266 		return MEM_LPDDR3;
267 	case 3:
268 		return MEM_LPDDR4;
269 	case 4:
270 		return MEM_WIO2;
271 	default:
272 		return MEM_UNKNOWN;
273 	}
274 }
275 
276 static int decode_chan_idx(u64 addr, u64 mask, int intlv_bit)
277 {
278 	u64 hash_addr = addr & mask, hash = 0;
279 	u64 intlv = (addr >> intlv_bit) & 1;
280 	int i;
281 
282 	for (i = 6; i < 20; i++)
283 		hash ^= (hash_addr >> i) & 1;
284 
285 	return (int)hash ^ intlv;
286 }
287 
288 static u64 decode_channel_addr(u64 addr, int intlv_bit)
289 {
290 	u64 channel_addr;
291 
292 	/* Remove the interleave bit and shift upper part down to fill gap */
293 	channel_addr  = GET_BITFIELD(addr, intlv_bit + 1, 63) << intlv_bit;
294 	channel_addr |= GET_BITFIELD(addr, 0, intlv_bit - 1);
295 
296 	return channel_addr;
297 }
298 
299 static void decode_addr(u64 addr, u32 hash, u64 s_size, int l_map,
300 			int *idx, u64 *sub_addr)
301 {
302 	int intlv_bit = CHANNEL_HASH_LSB_MASK_BIT(hash) + 6;
303 
304 	if (addr > 2 * s_size) {
305 		*sub_addr = addr - s_size;
306 		*idx = l_map;
307 		return;
308 	}
309 
310 	if (CHANNEL_HASH_MODE(hash)) {
311 		*sub_addr = decode_channel_addr(addr, intlv_bit);
312 		*idx = decode_chan_idx(addr, CHANNEL_HASH_MASK(hash), intlv_bit);
313 	} else {
314 		*sub_addr = decode_channel_addr(addr, 6);
315 		*idx = GET_BITFIELD(addr, 6, 6);
316 	}
317 }
318 
319 static int igen6_decode(struct decoded_addr *res)
320 {
321 	struct igen6_imc *imc = &igen6_pvt->imc[res->mc];
322 	u64 addr = res->imc_addr, sub_addr, s_size;
323 	int idx, l_map;
324 	u32 hash;
325 
326 	if (addr >= igen6_tom) {
327 		edac_dbg(0, "Address 0x%llx out of range\n", addr);
328 		return -EINVAL;
329 	}
330 
331 	/* Decode channel */
332 	hash   = readl(imc->window + CHANNEL_HASH_OFFSET);
333 	s_size = imc->ch_s_size;
334 	l_map  = imc->ch_l_map;
335 	decode_addr(addr, hash, s_size, l_map, &idx, &sub_addr);
336 	res->channel_idx  = idx;
337 	res->channel_addr = sub_addr;
338 
339 	/* Decode sub-channel/DIMM */
340 	hash   = readl(imc->window + CHANNEL_EHASH_OFFSET);
341 	s_size = imc->dimm_s_size[idx];
342 	l_map  = imc->dimm_l_map[idx];
343 	decode_addr(res->channel_addr, hash, s_size, l_map, &idx, &sub_addr);
344 	res->sub_channel_idx  = idx;
345 	res->sub_channel_addr = sub_addr;
346 
347 	return 0;
348 }
349 
350 static void igen6_output_error(struct decoded_addr *res,
351 			       struct mem_ctl_info *mci, u64 ecclog)
352 {
353 	enum hw_event_mc_err_type type = ecclog & ECC_ERROR_LOG_UE ?
354 					 HW_EVENT_ERR_UNCORRECTED :
355 					 HW_EVENT_ERR_CORRECTED;
356 
357 	edac_mc_handle_error(type, mci, 1,
358 			     res->sys_addr >> PAGE_SHIFT,
359 			     res->sys_addr & ~PAGE_MASK,
360 			     ECC_ERROR_LOG_SYND(ecclog),
361 			     res->channel_idx, res->sub_channel_idx,
362 			     -1, "", "");
363 }
364 
365 static struct gen_pool *ecclog_gen_pool_create(void)
366 {
367 	struct gen_pool *pool;
368 
369 	pool = gen_pool_create(ilog2(sizeof(struct ecclog_node)), -1);
370 	if (!pool)
371 		return NULL;
372 
373 	if (gen_pool_add(pool, (unsigned long)ecclog_buf, ECCLOG_POOL_SIZE, -1)) {
374 		gen_pool_destroy(pool);
375 		return NULL;
376 	}
377 
378 	return pool;
379 }
380 
381 static int ecclog_gen_pool_add(int mc, u64 ecclog)
382 {
383 	struct ecclog_node *node;
384 
385 	node = (void *)gen_pool_alloc(ecclog_pool, sizeof(*node));
386 	if (!node)
387 		return -ENOMEM;
388 
389 	node->mc = mc;
390 	node->ecclog = ecclog;
391 	llist_add(&node->llnode, &ecclog_llist);
392 
393 	return 0;
394 }
395 
396 /*
397  * Either the memory-mapped I/O status register ECC_ERROR_LOG or the PCI
398  * configuration space status register ERRSTS can indicate whether a
399  * correctable error or an uncorrectable error occurred. We only use the
400  * ECC_ERROR_LOG register to check error type, but need to clear both
401  * registers to enable future error events.
402  */
403 static u64 ecclog_read_and_clear(struct igen6_imc *imc)
404 {
405 	u64 ecclog = readq(imc->window + ECC_ERROR_LOG_OFFSET);
406 
407 	if (ecclog & (ECC_ERROR_LOG_CE | ECC_ERROR_LOG_UE)) {
408 		/* Clear CE/UE bits by writing 1s */
409 		writeq(ecclog, imc->window + ECC_ERROR_LOG_OFFSET);
410 		return ecclog;
411 	}
412 
413 	return 0;
414 }
415 
416 static void errsts_clear(struct igen6_imc *imc)
417 {
418 	u16 errsts;
419 
420 	if (pci_read_config_word(imc->pdev, ERRSTS_OFFSET, &errsts)) {
421 		igen6_printk(KERN_ERR, "Failed to read ERRSTS\n");
422 		return;
423 	}
424 
425 	/* Clear CE/UE bits by writing 1s */
426 	if (errsts & (ERRSTS_CE | ERRSTS_UE))
427 		pci_write_config_word(imc->pdev, ERRSTS_OFFSET, errsts);
428 }
429 
430 static int errcmd_enable_error_reporting(bool enable)
431 {
432 	struct igen6_imc *imc = &igen6_pvt->imc[0];
433 	u16 errcmd;
434 	int rc;
435 
436 	rc = pci_read_config_word(imc->pdev, ERRCMD_OFFSET, &errcmd);
437 	if (rc)
438 		return rc;
439 
440 	if (enable)
441 		errcmd |= ERRCMD_CE | ERRSTS_UE;
442 	else
443 		errcmd &= ~(ERRCMD_CE | ERRSTS_UE);
444 
445 	rc = pci_write_config_word(imc->pdev, ERRCMD_OFFSET, errcmd);
446 	if (rc)
447 		return rc;
448 
449 	return 0;
450 }
451 
452 static int ecclog_handler(void)
453 {
454 	struct igen6_imc *imc;
455 	int i, n = 0;
456 	u64 ecclog;
457 
458 	for (i = 0; i < res_cfg->num_imc; i++) {
459 		imc = &igen6_pvt->imc[i];
460 
461 		/* errsts_clear() isn't NMI-safe. Delay it in the IRQ context */
462 
463 		ecclog = ecclog_read_and_clear(imc);
464 		if (!ecclog)
465 			continue;
466 
467 		if (!ecclog_gen_pool_add(i, ecclog))
468 			irq_work_queue(&ecclog_irq_work);
469 
470 		n++;
471 	}
472 
473 	return n;
474 }
475 
476 static void ecclog_work_cb(struct work_struct *work)
477 {
478 	struct ecclog_node *node, *tmp;
479 	struct mem_ctl_info *mci;
480 	struct llist_node *head;
481 	struct decoded_addr res;
482 	u64 eaddr;
483 
484 	head = llist_del_all(&ecclog_llist);
485 	if (!head)
486 		return;
487 
488 	llist_for_each_entry_safe(node, tmp, head, llnode) {
489 		memset(&res, 0, sizeof(res));
490 		eaddr = ECC_ERROR_LOG_ADDR(node->ecclog) <<
491 			ECC_ERROR_LOG_ADDR_SHIFT;
492 		res.mc	     = node->mc;
493 		res.sys_addr = res_cfg->err_addr_to_sys_addr(eaddr);
494 		res.imc_addr = res_cfg->err_addr_to_imc_addr(eaddr);
495 
496 		mci = igen6_pvt->imc[res.mc].mci;
497 
498 		edac_dbg(2, "MC %d, ecclog = 0x%llx\n", node->mc, node->ecclog);
499 		igen6_mc_printk(mci, KERN_DEBUG, "HANDLING IBECC MEMORY ERROR\n");
500 		igen6_mc_printk(mci, KERN_DEBUG, "ADDR 0x%llx ", res.sys_addr);
501 
502 		if (!igen6_decode(&res))
503 			igen6_output_error(&res, mci, node->ecclog);
504 
505 		gen_pool_free(ecclog_pool, (unsigned long)node, sizeof(*node));
506 	}
507 }
508 
509 static void ecclog_irq_work_cb(struct irq_work *irq_work)
510 {
511 	int i;
512 
513 	for (i = 0; i < res_cfg->num_imc; i++)
514 		errsts_clear(&igen6_pvt->imc[i]);
515 
516 	if (!llist_empty(&ecclog_llist))
517 		schedule_work(&ecclog_work);
518 }
519 
520 static int ecclog_nmi_handler(unsigned int cmd, struct pt_regs *regs)
521 {
522 	unsigned char reason;
523 
524 	if (!ecclog_handler())
525 		return NMI_DONE;
526 
527 	/*
528 	 * Both In-Band ECC correctable error and uncorrectable error are
529 	 * reported by SERR# NMI. The NMI generic code (see pci_serr_error())
530 	 * doesn't clear the bit NMI_REASON_CLEAR_SERR (in port 0x61) to
531 	 * re-enable the SERR# NMI after NMI handling. So clear this bit here
532 	 * to re-enable SERR# NMI for receiving future In-Band ECC errors.
533 	 */
534 	reason  = x86_platform.get_nmi_reason() & NMI_REASON_CLEAR_MASK;
535 	reason |= NMI_REASON_CLEAR_SERR;
536 	outb(reason, NMI_REASON_PORT);
537 	reason &= ~NMI_REASON_CLEAR_SERR;
538 	outb(reason, NMI_REASON_PORT);
539 
540 	return NMI_HANDLED;
541 }
542 
543 static bool igen6_check_ecc(struct igen6_imc *imc)
544 {
545 	u32 activate = readl(imc->window + IBECC_ACTIVATE_OFFSET);
546 
547 	return !!(activate & IBECC_ACTIVATE_EN);
548 }
549 
550 static int igen6_get_dimm_config(struct mem_ctl_info *mci)
551 {
552 	struct igen6_imc *imc = mci->pvt_info;
553 	u32 mad_inter, mad_intra, mad_dimm;
554 	int i, j, ndimms, mc = imc->mc;
555 	struct dimm_info *dimm;
556 	enum mem_type mtype;
557 	enum dev_type dtype;
558 	u64 dsize;
559 	bool ecc;
560 
561 	edac_dbg(2, "\n");
562 
563 	mad_inter = readl(imc->window + MAD_INTER_CHANNEL_OFFSET);
564 	mtype = get_memory_type(mad_inter);
565 	ecc = igen6_check_ecc(imc);
566 	imc->ch_s_size = MAD_INTER_CHANNEL_CH_S_SIZE(mad_inter);
567 	imc->ch_l_map  = MAD_INTER_CHANNEL_CH_L_MAP(mad_inter);
568 
569 	for (i = 0; i < NUM_CHANNELS; i++) {
570 		mad_intra = readl(imc->window + MAD_INTRA_CH0_OFFSET + i * 4);
571 		mad_dimm  = readl(imc->window + MAD_DIMM_CH0_OFFSET + i * 4);
572 
573 		imc->dimm_l_size[i] = MAD_DIMM_CH_DIMM_L_SIZE(mad_dimm);
574 		imc->dimm_s_size[i] = MAD_DIMM_CH_DIMM_S_SIZE(mad_dimm);
575 		imc->dimm_l_map[i]  = MAD_INTRA_CH_DIMM_L_MAP(mad_intra);
576 		ndimms = 0;
577 
578 		for (j = 0; j < NUM_DIMMS; j++) {
579 			dimm = edac_get_dimm(mci, i, j, 0);
580 
581 			if (j ^ imc->dimm_l_map[i]) {
582 				dtype = get_width(0, mad_dimm);
583 				dsize = imc->dimm_s_size[i];
584 			} else {
585 				dtype = get_width(1, mad_dimm);
586 				dsize = imc->dimm_l_size[i];
587 			}
588 
589 			if (!dsize)
590 				continue;
591 
592 			dimm->grain = 64;
593 			dimm->mtype = mtype;
594 			dimm->dtype = dtype;
595 			dimm->nr_pages  = MiB_TO_PAGES(dsize >> 20);
596 			dimm->edac_mode = EDAC_SECDED;
597 			snprintf(dimm->label, sizeof(dimm->label),
598 				 "MC#%d_Chan#%d_DIMM#%d", mc, i, j);
599 			edac_dbg(0, "MC %d, Channel %d, DIMM %d, Size %llu MiB (%u pages)\n",
600 				 mc, i, j, dsize >> 20, dimm->nr_pages);
601 
602 			ndimms++;
603 		}
604 
605 		if (ndimms && !ecc) {
606 			igen6_printk(KERN_ERR, "MC%d In-Band ECC is disabled\n", mc);
607 			return -ENODEV;
608 		}
609 	}
610 
611 	return 0;
612 }
613 
614 #ifdef CONFIG_EDAC_DEBUG
615 /* Top of upper usable DRAM */
616 static u64 igen6_touud;
617 #define TOUUD_OFFSET	0xa8
618 
619 static void igen6_reg_dump(struct igen6_imc *imc)
620 {
621 	int i;
622 
623 	edac_dbg(2, "CHANNEL_HASH     : 0x%x\n",
624 		 readl(imc->window + CHANNEL_HASH_OFFSET));
625 	edac_dbg(2, "CHANNEL_EHASH    : 0x%x\n",
626 		 readl(imc->window + CHANNEL_EHASH_OFFSET));
627 	edac_dbg(2, "MAD_INTER_CHANNEL: 0x%x\n",
628 		 readl(imc->window + MAD_INTER_CHANNEL_OFFSET));
629 	edac_dbg(2, "ECC_ERROR_LOG    : 0x%llx\n",
630 		 readq(imc->window + ECC_ERROR_LOG_OFFSET));
631 
632 	for (i = 0; i < NUM_CHANNELS; i++) {
633 		edac_dbg(2, "MAD_INTRA_CH%d    : 0x%x\n", i,
634 			 readl(imc->window + MAD_INTRA_CH0_OFFSET + i * 4));
635 		edac_dbg(2, "MAD_DIMM_CH%d     : 0x%x\n", i,
636 			 readl(imc->window + MAD_DIMM_CH0_OFFSET + i * 4));
637 	}
638 	edac_dbg(2, "TOLUD            : 0x%x", igen6_tolud);
639 	edac_dbg(2, "TOUUD            : 0x%llx", igen6_touud);
640 	edac_dbg(2, "TOM              : 0x%llx", igen6_tom);
641 }
642 
643 static struct dentry *igen6_test;
644 
645 static int debugfs_u64_set(void *data, u64 val)
646 {
647 	u64 ecclog;
648 
649 	if ((val >= igen6_tolud && val < _4GB) || val >= igen6_touud) {
650 		edac_dbg(0, "Address 0x%llx out of range\n", val);
651 		return 0;
652 	}
653 
654 	pr_warn_once("Fake error to 0x%llx injected via debugfs\n", val);
655 
656 	val  >>= ECC_ERROR_LOG_ADDR_SHIFT;
657 	ecclog = (val << ECC_ERROR_LOG_ADDR_SHIFT) | ECC_ERROR_LOG_CE;
658 
659 	if (!ecclog_gen_pool_add(0, ecclog))
660 		irq_work_queue(&ecclog_irq_work);
661 
662 	return 0;
663 }
664 DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
665 
666 static void igen6_debug_setup(void)
667 {
668 	igen6_test = edac_debugfs_create_dir("igen6_test");
669 	if (!igen6_test)
670 		return;
671 
672 	if (!edac_debugfs_create_file("addr", 0200, igen6_test,
673 				      NULL, &fops_u64_wo)) {
674 		debugfs_remove(igen6_test);
675 		igen6_test = NULL;
676 	}
677 }
678 
679 static void igen6_debug_teardown(void)
680 {
681 	debugfs_remove_recursive(igen6_test);
682 }
683 #else
684 static void igen6_reg_dump(struct igen6_imc *imc) {}
685 static void igen6_debug_setup(void) {}
686 static void igen6_debug_teardown(void) {}
687 #endif
688 
689 static int igen6_pci_setup(struct pci_dev *pdev, u64 *mchbar)
690 {
691 	union  {
692 		u64 v;
693 		struct {
694 			u32 v_lo;
695 			u32 v_hi;
696 		};
697 	} u;
698 
699 	edac_dbg(2, "\n");
700 
701 	if (!res_cfg->ibecc_available(pdev)) {
702 		edac_dbg(2, "No In-Band ECC IP\n");
703 		goto fail;
704 	}
705 
706 	if (pci_read_config_dword(pdev, TOLUD_OFFSET, &igen6_tolud)) {
707 		igen6_printk(KERN_ERR, "Failed to read TOLUD\n");
708 		goto fail;
709 	}
710 
711 	igen6_tolud &= GENMASK(31, 20);
712 
713 	if (pci_read_config_dword(pdev, TOM_OFFSET, &u.v_lo)) {
714 		igen6_printk(KERN_ERR, "Failed to read lower TOM\n");
715 		goto fail;
716 	}
717 
718 	if (pci_read_config_dword(pdev, TOM_OFFSET + 4, &u.v_hi)) {
719 		igen6_printk(KERN_ERR, "Failed to read upper TOM\n");
720 		goto fail;
721 	}
722 
723 	igen6_tom = u.v & GENMASK_ULL(38, 20);
724 
725 	if (pci_read_config_dword(pdev, MCHBAR_OFFSET, &u.v_lo)) {
726 		igen6_printk(KERN_ERR, "Failed to read lower MCHBAR\n");
727 		goto fail;
728 	}
729 
730 	if (pci_read_config_dword(pdev, MCHBAR_OFFSET + 4, &u.v_hi)) {
731 		igen6_printk(KERN_ERR, "Failed to read upper MCHBAR\n");
732 		goto fail;
733 	}
734 
735 	if (!(u.v & MCHBAR_EN)) {
736 		igen6_printk(KERN_ERR, "MCHBAR is disabled\n");
737 		goto fail;
738 	}
739 
740 	*mchbar = MCHBAR_BASE(u.v);
741 
742 #ifdef CONFIG_EDAC_DEBUG
743 	if (pci_read_config_dword(pdev, TOUUD_OFFSET, &u.v_lo))
744 		edac_dbg(2, "Failed to read lower TOUUD\n");
745 	else if (pci_read_config_dword(pdev, TOUUD_OFFSET + 4, &u.v_hi))
746 		edac_dbg(2, "Failed to read upper TOUUD\n");
747 	else
748 		igen6_touud = u.v & GENMASK_ULL(38, 20);
749 #endif
750 
751 	return 0;
752 fail:
753 	return -ENODEV;
754 }
755 
756 static int igen6_register_mci(int mc, u64 mchbar, struct pci_dev *pdev)
757 {
758 	struct edac_mc_layer layers[2];
759 	struct mem_ctl_info *mci;
760 	struct igen6_imc *imc;
761 	void __iomem *window;
762 	int rc;
763 
764 	edac_dbg(2, "\n");
765 
766 	mchbar += mc * MCHBAR_SIZE;
767 	window = ioremap(mchbar, MCHBAR_SIZE);
768 	if (!window) {
769 		igen6_printk(KERN_ERR, "Failed to ioremap 0x%llx\n", mchbar);
770 		return -ENODEV;
771 	}
772 
773 	layers[0].type = EDAC_MC_LAYER_CHANNEL;
774 	layers[0].size = NUM_CHANNELS;
775 	layers[0].is_virt_csrow = false;
776 	layers[1].type = EDAC_MC_LAYER_SLOT;
777 	layers[1].size = NUM_DIMMS;
778 	layers[1].is_virt_csrow = true;
779 
780 	mci = edac_mc_alloc(mc, ARRAY_SIZE(layers), layers, 0);
781 	if (!mci) {
782 		rc = -ENOMEM;
783 		goto fail;
784 	}
785 
786 	mci->ctl_name = kasprintf(GFP_KERNEL, "Intel_client_SoC MC#%d", mc);
787 	if (!mci->ctl_name) {
788 		rc = -ENOMEM;
789 		goto fail2;
790 	}
791 
792 	mci->mtype_cap = MEM_FLAG_LPDDR4 | MEM_FLAG_DDR4;
793 	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
794 	mci->edac_cap = EDAC_FLAG_SECDED;
795 	mci->mod_name = EDAC_MOD_STR;
796 	mci->dev_name = pci_name(pdev);
797 	mci->pvt_info = &igen6_pvt->imc[mc];
798 
799 	imc = mci->pvt_info;
800 	device_initialize(&imc->dev);
801 	/*
802 	 * EDAC core uses mci->pdev(pointer of structure device) as
803 	 * memory controller ID. The client SoCs attach one or more
804 	 * memory controllers to single pci_dev (single pci_dev->dev
805 	 * can be for multiple memory controllers).
806 	 *
807 	 * To make mci->pdev unique, assign pci_dev->dev to mci->pdev
808 	 * for the first memory controller and assign a unique imc->dev
809 	 * to mci->pdev for each non-first memory controller.
810 	 */
811 	mci->pdev = mc ? &imc->dev : &pdev->dev;
812 	imc->mc	= mc;
813 	imc->pdev = pdev;
814 	imc->window = window;
815 
816 	igen6_reg_dump(imc);
817 
818 	rc = igen6_get_dimm_config(mci);
819 	if (rc)
820 		goto fail3;
821 
822 	rc = edac_mc_add_mc(mci);
823 	if (rc) {
824 		igen6_printk(KERN_ERR, "Failed to register mci#%d\n", mc);
825 		goto fail3;
826 	}
827 
828 	imc->mci = mci;
829 	return 0;
830 fail3:
831 	kfree(mci->ctl_name);
832 fail2:
833 	edac_mc_free(mci);
834 fail:
835 	iounmap(window);
836 	return rc;
837 }
838 
839 static void igen6_unregister_mcis(void)
840 {
841 	struct mem_ctl_info *mci;
842 	struct igen6_imc *imc;
843 	int i;
844 
845 	edac_dbg(2, "\n");
846 
847 	for (i = 0; i < res_cfg->num_imc; i++) {
848 		imc = &igen6_pvt->imc[i];
849 		mci = imc->mci;
850 		if (!mci)
851 			continue;
852 
853 		edac_mc_del_mc(mci->pdev);
854 		kfree(mci->ctl_name);
855 		edac_mc_free(mci);
856 		iounmap(imc->window);
857 	}
858 }
859 
860 static int igen6_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
861 {
862 	u64 mchbar;
863 	int i, rc;
864 
865 	edac_dbg(2, "\n");
866 
867 	igen6_pvt = kzalloc(sizeof(*igen6_pvt), GFP_KERNEL);
868 	if (!igen6_pvt)
869 		return -ENOMEM;
870 
871 	res_cfg = (struct res_config *)ent->driver_data;
872 
873 	rc = igen6_pci_setup(pdev, &mchbar);
874 	if (rc)
875 		goto fail;
876 
877 	for (i = 0; i < res_cfg->num_imc; i++) {
878 		rc = igen6_register_mci(i, mchbar, pdev);
879 		if (rc)
880 			goto fail2;
881 	}
882 
883 	ecclog_pool = ecclog_gen_pool_create();
884 	if (!ecclog_pool) {
885 		rc = -ENOMEM;
886 		goto fail2;
887 	}
888 
889 	INIT_WORK(&ecclog_work, ecclog_work_cb);
890 	init_irq_work(&ecclog_irq_work, ecclog_irq_work_cb);
891 
892 	/* Check if any pending errors before registering the NMI handler */
893 	ecclog_handler();
894 
895 	rc = register_nmi_handler(NMI_SERR, ecclog_nmi_handler,
896 				  0, IGEN6_NMI_NAME);
897 	if (rc) {
898 		igen6_printk(KERN_ERR, "Failed to register NMI handler\n");
899 		goto fail3;
900 	}
901 
902 	/* Enable error reporting */
903 	rc = errcmd_enable_error_reporting(true);
904 	if (rc) {
905 		igen6_printk(KERN_ERR, "Failed to enable error reporting\n");
906 		goto fail4;
907 	}
908 
909 	igen6_debug_setup();
910 	return 0;
911 fail4:
912 	unregister_nmi_handler(NMI_SERR, IGEN6_NMI_NAME);
913 fail3:
914 	gen_pool_destroy(ecclog_pool);
915 fail2:
916 	igen6_unregister_mcis();
917 fail:
918 	kfree(igen6_pvt);
919 	return rc;
920 }
921 
922 static void igen6_remove(struct pci_dev *pdev)
923 {
924 	edac_dbg(2, "\n");
925 
926 	igen6_debug_teardown();
927 	errcmd_enable_error_reporting(false);
928 	unregister_nmi_handler(NMI_SERR, IGEN6_NMI_NAME);
929 	irq_work_sync(&ecclog_irq_work);
930 	flush_work(&ecclog_work);
931 	gen_pool_destroy(ecclog_pool);
932 	igen6_unregister_mcis();
933 	kfree(igen6_pvt);
934 }
935 
936 static struct pci_driver igen6_driver = {
937 	.name     = EDAC_MOD_STR,
938 	.probe    = igen6_probe,
939 	.remove   = igen6_remove,
940 	.id_table = igen6_pci_tbl,
941 };
942 
943 static int __init igen6_init(void)
944 {
945 	const char *owner;
946 	int rc;
947 
948 	edac_dbg(2, "\n");
949 
950 	owner = edac_get_owner();
951 	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
952 		return -ENODEV;
953 
954 	edac_op_state = EDAC_OPSTATE_NMI;
955 
956 	rc = pci_register_driver(&igen6_driver);
957 	if (rc)
958 		return rc;
959 
960 	igen6_printk(KERN_INFO, "%s\n", IGEN6_REVISION);
961 
962 	return 0;
963 }
964 
965 static void __exit igen6_exit(void)
966 {
967 	edac_dbg(2, "\n");
968 
969 	pci_unregister_driver(&igen6_driver);
970 }
971 
972 module_init(igen6_init);
973 module_exit(igen6_exit);
974 
975 MODULE_LICENSE("GPL v2");
976 MODULE_AUTHOR("Qiuxu Zhuo");
977 MODULE_DESCRIPTION("MC Driver for Intel client SoC using In-Band ECC");
978