xref: /openbmc/linux/arch/x86/kernel/cpu/mce/amd.c (revision e657c18a)
1 /*
2  *  (c) 2005-2016 Advanced Micro Devices, Inc.
3  *  Your use of this code is subject to the terms and conditions of the
4  *  GNU general public license version 2. See "COPYING" or
5  *  http://www.gnu.org/licenses/gpl.html
6  *
7  *  Written by Jacob Shin - AMD, Inc.
8  *  Maintained by: Borislav Petkov <bp@alien8.de>
9  *
10  *  All MC4_MISCi registers are shared between cores on a node.
11  */
12 #include <linux/interrupt.h>
13 #include <linux/notifier.h>
14 #include <linux/kobject.h>
15 #include <linux/percpu.h>
16 #include <linux/errno.h>
17 #include <linux/sched.h>
18 #include <linux/sysfs.h>
19 #include <linux/slab.h>
20 #include <linux/init.h>
21 #include <linux/cpu.h>
22 #include <linux/smp.h>
23 #include <linux/string.h>
24 
25 #include <asm/amd_nb.h>
26 #include <asm/traps.h>
27 #include <asm/apic.h>
28 #include <asm/mce.h>
29 #include <asm/msr.h>
30 #include <asm/trace/irq_vectors.h>
31 
32 #include "internal.h"
33 
34 #define NR_BLOCKS         5
35 #define THRESHOLD_MAX     0xFFF
36 #define INT_TYPE_APIC     0x00020000
37 #define MASK_VALID_HI     0x80000000
38 #define MASK_CNTP_HI      0x40000000
39 #define MASK_LOCKED_HI    0x20000000
40 #define MASK_LVTOFF_HI    0x00F00000
41 #define MASK_COUNT_EN_HI  0x00080000
42 #define MASK_INT_TYPE_HI  0x00060000
43 #define MASK_OVERFLOW_HI  0x00010000
44 #define MASK_ERR_COUNT_HI 0x00000FFF
45 #define MASK_BLKPTR_LO    0xFF000000
46 #define MCG_XBLK_ADDR     0xC0000400
47 
48 /* Deferred error settings */
49 #define MSR_CU_DEF_ERR		0xC0000410
50 #define MASK_DEF_LVTOFF		0x000000F0
51 #define MASK_DEF_INT_TYPE	0x00000006
52 #define DEF_LVT_OFF		0x2
53 #define DEF_INT_TYPE_APIC	0x2
54 
55 /* Scalable MCA: */
56 
57 /* Threshold LVT offset is at MSR0xC0000410[15:12] */
58 #define SMCA_THR_LVT_OFF	0xF000
59 
60 static bool thresholding_irq_en;
61 
62 static const char * const th_names[] = {
63 	"load_store",
64 	"insn_fetch",
65 	"combined_unit",
66 	"decode_unit",
67 	"northbridge",
68 	"execution_unit",
69 };
70 
71 static const char * const smca_umc_block_names[] = {
72 	"dram_ecc",
73 	"misc_umc"
74 };
75 
76 struct smca_bank_name {
77 	const char *name;	/* Short name for sysfs */
78 	const char *long_name;	/* Long name for pretty-printing */
79 };
80 
81 static struct smca_bank_name smca_names[] = {
82 	[SMCA_LS]	= { "load_store",	"Load Store Unit" },
83 	[SMCA_IF]	= { "insn_fetch",	"Instruction Fetch Unit" },
84 	[SMCA_L2_CACHE]	= { "l2_cache",		"L2 Cache" },
85 	[SMCA_DE]	= { "decode_unit",	"Decode Unit" },
86 	[SMCA_RESERVED]	= { "reserved",		"Reserved" },
87 	[SMCA_EX]	= { "execution_unit",	"Execution Unit" },
88 	[SMCA_FP]	= { "floating_point",	"Floating Point Unit" },
89 	[SMCA_L3_CACHE]	= { "l3_cache",		"L3 Cache" },
90 	[SMCA_CS]	= { "coherent_slave",	"Coherent Slave" },
91 	[SMCA_CS_V2]	= { "coherent_slave",	"Coherent Slave" },
92 	[SMCA_PIE]	= { "pie",		"Power, Interrupts, etc." },
93 	[SMCA_UMC]	= { "umc",		"Unified Memory Controller" },
94 	[SMCA_PB]	= { "param_block",	"Parameter Block" },
95 	[SMCA_PSP]	= { "psp",		"Platform Security Processor" },
96 	[SMCA_PSP_V2]	= { "psp",		"Platform Security Processor" },
97 	[SMCA_SMU]	= { "smu",		"System Management Unit" },
98 	[SMCA_SMU_V2]	= { "smu",		"System Management Unit" },
99 	[SMCA_MP5]	= { "mp5",		"Microprocessor 5 Unit" },
100 	[SMCA_NBIO]	= { "nbio",		"Northbridge IO Unit" },
101 	[SMCA_PCIE]	= { "pcie",		"PCI Express Unit" },
102 };
103 
104 static u32 smca_bank_addrs[MAX_NR_BANKS][NR_BLOCKS] __ro_after_init =
105 {
106 	[0 ... MAX_NR_BANKS - 1] = { [0 ... NR_BLOCKS - 1] = -1 }
107 };
108 
109 static const char *smca_get_name(enum smca_bank_types t)
110 {
111 	if (t >= N_SMCA_BANK_TYPES)
112 		return NULL;
113 
114 	return smca_names[t].name;
115 }
116 
117 const char *smca_get_long_name(enum smca_bank_types t)
118 {
119 	if (t >= N_SMCA_BANK_TYPES)
120 		return NULL;
121 
122 	return smca_names[t].long_name;
123 }
124 EXPORT_SYMBOL_GPL(smca_get_long_name);
125 
126 static enum smca_bank_types smca_get_bank_type(unsigned int bank)
127 {
128 	struct smca_bank *b;
129 
130 	if (bank >= MAX_NR_BANKS)
131 		return N_SMCA_BANK_TYPES;
132 
133 	b = &smca_banks[bank];
134 	if (!b->hwid)
135 		return N_SMCA_BANK_TYPES;
136 
137 	return b->hwid->bank_type;
138 }
139 
140 static struct smca_hwid smca_hwid_mcatypes[] = {
141 	/* { bank_type, hwid_mcatype, xec_bitmap } */
142 
143 	/* Reserved type */
144 	{ SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0), 0x0 },
145 
146 	/* ZN Core (HWID=0xB0) MCA types */
147 	{ SMCA_LS,	 HWID_MCATYPE(0xB0, 0x0), 0x1FFFFF },
148 	{ SMCA_IF,	 HWID_MCATYPE(0xB0, 0x1), 0x3FFF },
149 	{ SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2), 0xF },
150 	{ SMCA_DE,	 HWID_MCATYPE(0xB0, 0x3), 0x1FF },
151 	/* HWID 0xB0 MCATYPE 0x4 is Reserved */
152 	{ SMCA_EX,	 HWID_MCATYPE(0xB0, 0x5), 0xFFF },
153 	{ SMCA_FP,	 HWID_MCATYPE(0xB0, 0x6), 0x7F },
154 	{ SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7), 0xFF },
155 
156 	/* Data Fabric MCA types */
157 	{ SMCA_CS,	 HWID_MCATYPE(0x2E, 0x0), 0x1FF },
158 	{ SMCA_PIE,	 HWID_MCATYPE(0x2E, 0x1), 0x1F },
159 	{ SMCA_CS_V2,	 HWID_MCATYPE(0x2E, 0x2), 0x3FFF },
160 
161 	/* Unified Memory Controller MCA type */
162 	{ SMCA_UMC,	 HWID_MCATYPE(0x96, 0x0), 0xFF },
163 
164 	/* Parameter Block MCA type */
165 	{ SMCA_PB,	 HWID_MCATYPE(0x05, 0x0), 0x1 },
166 
167 	/* Platform Security Processor MCA type */
168 	{ SMCA_PSP,	 HWID_MCATYPE(0xFF, 0x0), 0x1 },
169 	{ SMCA_PSP_V2,	 HWID_MCATYPE(0xFF, 0x1), 0x3FFFF },
170 
171 	/* System Management Unit MCA type */
172 	{ SMCA_SMU,	 HWID_MCATYPE(0x01, 0x0), 0x1 },
173 	{ SMCA_SMU_V2,	 HWID_MCATYPE(0x01, 0x1), 0x7FF },
174 
175 	/* Microprocessor 5 Unit MCA type */
176 	{ SMCA_MP5,	 HWID_MCATYPE(0x01, 0x2), 0x3FF },
177 
178 	/* Northbridge IO Unit MCA type */
179 	{ SMCA_NBIO,	 HWID_MCATYPE(0x18, 0x0), 0x1F },
180 
181 	/* PCI Express Unit MCA type */
182 	{ SMCA_PCIE,	 HWID_MCATYPE(0x46, 0x0), 0x1F },
183 };
184 
185 struct smca_bank smca_banks[MAX_NR_BANKS];
186 EXPORT_SYMBOL_GPL(smca_banks);
187 
188 /*
189  * In SMCA enabled processors, we can have multiple banks for a given IP type.
190  * So to define a unique name for each bank, we use a temp c-string to append
191  * the MCA_IPID[InstanceId] to type's name in get_name().
192  *
193  * InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
194  * is greater than 8 plus 1 (for underscore) plus length of longest type name.
195  */
196 #define MAX_MCATYPE_NAME_LEN	30
197 static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
198 
199 static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
200 static DEFINE_PER_CPU(unsigned int, bank_map);	/* see which banks are on */
201 
202 static void amd_threshold_interrupt(void);
203 static void amd_deferred_error_interrupt(void);
204 
205 static void default_deferred_error_interrupt(void)
206 {
207 	pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
208 }
209 void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
210 
211 static void smca_configure(unsigned int bank, unsigned int cpu)
212 {
213 	unsigned int i, hwid_mcatype;
214 	struct smca_hwid *s_hwid;
215 	u32 high, low;
216 	u32 smca_config = MSR_AMD64_SMCA_MCx_CONFIG(bank);
217 
218 	/* Set appropriate bits in MCA_CONFIG */
219 	if (!rdmsr_safe(smca_config, &low, &high)) {
220 		/*
221 		 * OS is required to set the MCAX bit to acknowledge that it is
222 		 * now using the new MSR ranges and new registers under each
223 		 * bank. It also means that the OS will configure deferred
224 		 * errors in the new MCx_CONFIG register. If the bit is not set,
225 		 * uncorrectable errors will cause a system panic.
226 		 *
227 		 * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
228 		 */
229 		high |= BIT(0);
230 
231 		/*
232 		 * SMCA sets the Deferred Error Interrupt type per bank.
233 		 *
234 		 * MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
235 		 * if the DeferredIntType bit field is available.
236 		 *
237 		 * MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
238 		 * high portion of the MSR). OS should set this to 0x1 to enable
239 		 * APIC based interrupt. First, check that no interrupt has been
240 		 * set.
241 		 */
242 		if ((low & BIT(5)) && !((high >> 5) & 0x3))
243 			high |= BIT(5);
244 
245 		wrmsr(smca_config, low, high);
246 	}
247 
248 	/* Return early if this bank was already initialized. */
249 	if (smca_banks[bank].hwid)
250 		return;
251 
252 	if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
253 		pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
254 		return;
255 	}
256 
257 	hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
258 				    (high & MCI_IPID_MCATYPE) >> 16);
259 
260 	for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
261 		s_hwid = &smca_hwid_mcatypes[i];
262 		if (hwid_mcatype == s_hwid->hwid_mcatype) {
263 			smca_banks[bank].hwid = s_hwid;
264 			smca_banks[bank].id = low;
265 			smca_banks[bank].sysfs_id = s_hwid->count++;
266 			break;
267 		}
268 	}
269 }
270 
271 struct thresh_restart {
272 	struct threshold_block	*b;
273 	int			reset;
274 	int			set_lvt_off;
275 	int			lvt_off;
276 	u16			old_limit;
277 };
278 
279 static inline bool is_shared_bank(int bank)
280 {
281 	/*
282 	 * Scalable MCA provides for only one core to have access to the MSRs of
283 	 * a shared bank.
284 	 */
285 	if (mce_flags.smca)
286 		return false;
287 
288 	/* Bank 4 is for northbridge reporting and is thus shared */
289 	return (bank == 4);
290 }
291 
292 static const char *bank4_names(const struct threshold_block *b)
293 {
294 	switch (b->address) {
295 	/* MSR4_MISC0 */
296 	case 0x00000413:
297 		return "dram";
298 
299 	case 0xc0000408:
300 		return "ht_links";
301 
302 	case 0xc0000409:
303 		return "l3_cache";
304 
305 	default:
306 		WARN(1, "Funny MSR: 0x%08x\n", b->address);
307 		return "";
308 	}
309 };
310 
311 
312 static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
313 {
314 	/*
315 	 * bank 4 supports APIC LVT interrupts implicitly since forever.
316 	 */
317 	if (bank == 4)
318 		return true;
319 
320 	/*
321 	 * IntP: interrupt present; if this bit is set, the thresholding
322 	 * bank can generate APIC LVT interrupts
323 	 */
324 	return msr_high_bits & BIT(28);
325 }
326 
327 static int lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
328 {
329 	int msr = (hi & MASK_LVTOFF_HI) >> 20;
330 
331 	if (apic < 0) {
332 		pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
333 		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
334 		       b->bank, b->block, b->address, hi, lo);
335 		return 0;
336 	}
337 
338 	if (apic != msr) {
339 		/*
340 		 * On SMCA CPUs, LVT offset is programmed at a different MSR, and
341 		 * the BIOS provides the value. The original field where LVT offset
342 		 * was set is reserved. Return early here:
343 		 */
344 		if (mce_flags.smca)
345 			return 0;
346 
347 		pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
348 		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n",
349 		       b->cpu, apic, b->bank, b->block, b->address, hi, lo);
350 		return 0;
351 	}
352 
353 	return 1;
354 };
355 
356 /* Reprogram MCx_MISC MSR behind this threshold bank. */
357 static void threshold_restart_bank(void *_tr)
358 {
359 	struct thresh_restart *tr = _tr;
360 	u32 hi, lo;
361 
362 	rdmsr(tr->b->address, lo, hi);
363 
364 	if (tr->b->threshold_limit < (hi & THRESHOLD_MAX))
365 		tr->reset = 1;	/* limit cannot be lower than err count */
366 
367 	if (tr->reset) {		/* reset err count and overflow bit */
368 		hi =
369 		    (hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
370 		    (THRESHOLD_MAX - tr->b->threshold_limit);
371 	} else if (tr->old_limit) {	/* change limit w/o reset */
372 		int new_count = (hi & THRESHOLD_MAX) +
373 		    (tr->old_limit - tr->b->threshold_limit);
374 
375 		hi = (hi & ~MASK_ERR_COUNT_HI) |
376 		    (new_count & THRESHOLD_MAX);
377 	}
378 
379 	/* clear IntType */
380 	hi &= ~MASK_INT_TYPE_HI;
381 
382 	if (!tr->b->interrupt_capable)
383 		goto done;
384 
385 	if (tr->set_lvt_off) {
386 		if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
387 			/* set new lvt offset */
388 			hi &= ~MASK_LVTOFF_HI;
389 			hi |= tr->lvt_off << 20;
390 		}
391 	}
392 
393 	if (tr->b->interrupt_enable)
394 		hi |= INT_TYPE_APIC;
395 
396  done:
397 
398 	hi |= MASK_COUNT_EN_HI;
399 	wrmsr(tr->b->address, lo, hi);
400 }
401 
402 static void mce_threshold_block_init(struct threshold_block *b, int offset)
403 {
404 	struct thresh_restart tr = {
405 		.b			= b,
406 		.set_lvt_off		= 1,
407 		.lvt_off		= offset,
408 	};
409 
410 	b->threshold_limit		= THRESHOLD_MAX;
411 	threshold_restart_bank(&tr);
412 };
413 
414 static int setup_APIC_mce_threshold(int reserved, int new)
415 {
416 	if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
417 					      APIC_EILVT_MSG_FIX, 0))
418 		return new;
419 
420 	return reserved;
421 }
422 
423 static int setup_APIC_deferred_error(int reserved, int new)
424 {
425 	if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
426 					      APIC_EILVT_MSG_FIX, 0))
427 		return new;
428 
429 	return reserved;
430 }
431 
432 static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
433 {
434 	u32 low = 0, high = 0;
435 	int def_offset = -1, def_new;
436 
437 	if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
438 		return;
439 
440 	def_new = (low & MASK_DEF_LVTOFF) >> 4;
441 	if (!(low & MASK_DEF_LVTOFF)) {
442 		pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
443 		def_new = DEF_LVT_OFF;
444 		low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
445 	}
446 
447 	def_offset = setup_APIC_deferred_error(def_offset, def_new);
448 	if ((def_offset == def_new) &&
449 	    (deferred_error_int_vector != amd_deferred_error_interrupt))
450 		deferred_error_int_vector = amd_deferred_error_interrupt;
451 
452 	if (!mce_flags.smca)
453 		low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
454 
455 	wrmsr(MSR_CU_DEF_ERR, low, high);
456 }
457 
458 static u32 smca_get_block_address(unsigned int bank, unsigned int block)
459 {
460 	u32 low, high;
461 	u32 addr = 0;
462 
463 	if (smca_get_bank_type(bank) == SMCA_RESERVED)
464 		return addr;
465 
466 	if (!block)
467 		return MSR_AMD64_SMCA_MCx_MISC(bank);
468 
469 	/* Check our cache first: */
470 	if (smca_bank_addrs[bank][block] != -1)
471 		return smca_bank_addrs[bank][block];
472 
473 	/*
474 	 * For SMCA enabled processors, BLKPTR field of the first MISC register
475 	 * (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
476 	 */
477 	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
478 		goto out;
479 
480 	if (!(low & MCI_CONFIG_MCAX))
481 		goto out;
482 
483 	if (!rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high) &&
484 	    (low & MASK_BLKPTR_LO))
485 		addr = MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
486 
487 out:
488 	smca_bank_addrs[bank][block] = addr;
489 	return addr;
490 }
491 
492 static u32 get_block_address(u32 current_addr, u32 low, u32 high,
493 			     unsigned int bank, unsigned int block)
494 {
495 	u32 addr = 0, offset = 0;
496 
497 	if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
498 		return addr;
499 
500 	if (mce_flags.smca)
501 		return smca_get_block_address(bank, block);
502 
503 	/* Fall back to method we used for older processors: */
504 	switch (block) {
505 	case 0:
506 		addr = msr_ops.misc(bank);
507 		break;
508 	case 1:
509 		offset = ((low & MASK_BLKPTR_LO) >> 21);
510 		if (offset)
511 			addr = MCG_XBLK_ADDR + offset;
512 		break;
513 	default:
514 		addr = ++current_addr;
515 	}
516 	return addr;
517 }
518 
519 static int
520 prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
521 			int offset, u32 misc_high)
522 {
523 	unsigned int cpu = smp_processor_id();
524 	u32 smca_low, smca_high;
525 	struct threshold_block b;
526 	int new;
527 
528 	if (!block)
529 		per_cpu(bank_map, cpu) |= (1 << bank);
530 
531 	memset(&b, 0, sizeof(b));
532 	b.cpu			= cpu;
533 	b.bank			= bank;
534 	b.block			= block;
535 	b.address		= addr;
536 	b.interrupt_capable	= lvt_interrupt_supported(bank, misc_high);
537 
538 	if (!b.interrupt_capable)
539 		goto done;
540 
541 	b.interrupt_enable = 1;
542 
543 	if (!mce_flags.smca) {
544 		new = (misc_high & MASK_LVTOFF_HI) >> 20;
545 		goto set_offset;
546 	}
547 
548 	/* Gather LVT offset for thresholding: */
549 	if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
550 		goto out;
551 
552 	new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
553 
554 set_offset:
555 	offset = setup_APIC_mce_threshold(offset, new);
556 	if (offset == new)
557 		thresholding_irq_en = true;
558 
559 done:
560 	mce_threshold_block_init(&b, offset);
561 
562 out:
563 	return offset;
564 }
565 
566 /*
567  * Turn off MC4_MISC thresholding banks on all family 0x15 models since
568  * they're not supported there.
569  */
570 void disable_err_thresholding(struct cpuinfo_x86 *c)
571 {
572 	int i;
573 	u64 hwcr;
574 	bool need_toggle;
575 	u32 msrs[] = {
576 		0x00000413, /* MC4_MISC0 */
577 		0xc0000408, /* MC4_MISC1 */
578 	};
579 
580 	if (c->x86 != 0x15)
581 		return;
582 
583 	rdmsrl(MSR_K7_HWCR, hwcr);
584 
585 	/* McStatusWrEn has to be set */
586 	need_toggle = !(hwcr & BIT(18));
587 
588 	if (need_toggle)
589 		wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
590 
591 	/* Clear CntP bit safely */
592 	for (i = 0; i < ARRAY_SIZE(msrs); i++)
593 		msr_clear_bit(msrs[i], 62);
594 
595 	/* restore old settings */
596 	if (need_toggle)
597 		wrmsrl(MSR_K7_HWCR, hwcr);
598 }
599 
600 /* cpu init entry point, called from mce.c with preempt off */
601 void mce_amd_feature_init(struct cpuinfo_x86 *c)
602 {
603 	u32 low = 0, high = 0, address = 0;
604 	unsigned int bank, block, cpu = smp_processor_id();
605 	int offset = -1;
606 
607 	disable_err_thresholding(c);
608 
609 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
610 		if (mce_flags.smca)
611 			smca_configure(bank, cpu);
612 
613 		for (block = 0; block < NR_BLOCKS; ++block) {
614 			address = get_block_address(address, low, high, bank, block);
615 			if (!address)
616 				break;
617 
618 			if (rdmsr_safe(address, &low, &high))
619 				break;
620 
621 			if (!(high & MASK_VALID_HI))
622 				continue;
623 
624 			if (!(high & MASK_CNTP_HI)  ||
625 			     (high & MASK_LOCKED_HI))
626 				continue;
627 
628 			offset = prepare_threshold_block(bank, block, address, offset, high);
629 		}
630 	}
631 
632 	if (mce_flags.succor)
633 		deferred_error_interrupt_enable(c);
634 }
635 
636 int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
637 {
638 	u64 dram_base_addr, dram_limit_addr, dram_hole_base;
639 	/* We start from the normalized address */
640 	u64 ret_addr = norm_addr;
641 
642 	u32 tmp;
643 
644 	u8 die_id_shift, die_id_mask, socket_id_shift, socket_id_mask;
645 	u8 intlv_num_dies, intlv_num_chan, intlv_num_sockets;
646 	u8 intlv_addr_sel, intlv_addr_bit;
647 	u8 num_intlv_bits, hashed_bit;
648 	u8 lgcy_mmio_hole_en, base = 0;
649 	u8 cs_mask, cs_id = 0;
650 	bool hash_enabled = false;
651 
652 	/* Read D18F0x1B4 (DramOffset), check if base 1 is used. */
653 	if (amd_df_indirect_read(nid, 0, 0x1B4, umc, &tmp))
654 		goto out_err;
655 
656 	/* Remove HiAddrOffset from normalized address, if enabled: */
657 	if (tmp & BIT(0)) {
658 		u64 hi_addr_offset = (tmp & GENMASK_ULL(31, 20)) << 8;
659 
660 		if (norm_addr >= hi_addr_offset) {
661 			ret_addr -= hi_addr_offset;
662 			base = 1;
663 		}
664 	}
665 
666 	/* Read D18F0x110 (DramBaseAddress). */
667 	if (amd_df_indirect_read(nid, 0, 0x110 + (8 * base), umc, &tmp))
668 		goto out_err;
669 
670 	/* Check if address range is valid. */
671 	if (!(tmp & BIT(0))) {
672 		pr_err("%s: Invalid DramBaseAddress range: 0x%x.\n",
673 			__func__, tmp);
674 		goto out_err;
675 	}
676 
677 	lgcy_mmio_hole_en = tmp & BIT(1);
678 	intlv_num_chan	  = (tmp >> 4) & 0xF;
679 	intlv_addr_sel	  = (tmp >> 8) & 0x7;
680 	dram_base_addr	  = (tmp & GENMASK_ULL(31, 12)) << 16;
681 
682 	/* {0, 1, 2, 3} map to address bits {8, 9, 10, 11} respectively */
683 	if (intlv_addr_sel > 3) {
684 		pr_err("%s: Invalid interleave address select %d.\n",
685 			__func__, intlv_addr_sel);
686 		goto out_err;
687 	}
688 
689 	/* Read D18F0x114 (DramLimitAddress). */
690 	if (amd_df_indirect_read(nid, 0, 0x114 + (8 * base), umc, &tmp))
691 		goto out_err;
692 
693 	intlv_num_sockets = (tmp >> 8) & 0x1;
694 	intlv_num_dies	  = (tmp >> 10) & 0x3;
695 	dram_limit_addr	  = ((tmp & GENMASK_ULL(31, 12)) << 16) | GENMASK_ULL(27, 0);
696 
697 	intlv_addr_bit = intlv_addr_sel + 8;
698 
699 	/* Re-use intlv_num_chan by setting it equal to log2(#channels) */
700 	switch (intlv_num_chan) {
701 	case 0:	intlv_num_chan = 0; break;
702 	case 1: intlv_num_chan = 1; break;
703 	case 3: intlv_num_chan = 2; break;
704 	case 5:	intlv_num_chan = 3; break;
705 	case 7:	intlv_num_chan = 4; break;
706 
707 	case 8: intlv_num_chan = 1;
708 		hash_enabled = true;
709 		break;
710 	default:
711 		pr_err("%s: Invalid number of interleaved channels %d.\n",
712 			__func__, intlv_num_chan);
713 		goto out_err;
714 	}
715 
716 	num_intlv_bits = intlv_num_chan;
717 
718 	if (intlv_num_dies > 2) {
719 		pr_err("%s: Invalid number of interleaved nodes/dies %d.\n",
720 			__func__, intlv_num_dies);
721 		goto out_err;
722 	}
723 
724 	num_intlv_bits += intlv_num_dies;
725 
726 	/* Add a bit if sockets are interleaved. */
727 	num_intlv_bits += intlv_num_sockets;
728 
729 	/* Assert num_intlv_bits <= 4 */
730 	if (num_intlv_bits > 4) {
731 		pr_err("%s: Invalid interleave bits %d.\n",
732 			__func__, num_intlv_bits);
733 		goto out_err;
734 	}
735 
736 	if (num_intlv_bits > 0) {
737 		u64 temp_addr_x, temp_addr_i, temp_addr_y;
738 		u8 die_id_bit, sock_id_bit, cs_fabric_id;
739 
740 		/*
741 		 * Read FabricBlockInstanceInformation3_CS[BlockFabricID].
742 		 * This is the fabric id for this coherent slave. Use
743 		 * umc/channel# as instance id of the coherent slave
744 		 * for FICAA.
745 		 */
746 		if (amd_df_indirect_read(nid, 0, 0x50, umc, &tmp))
747 			goto out_err;
748 
749 		cs_fabric_id = (tmp >> 8) & 0xFF;
750 		die_id_bit   = 0;
751 
752 		/* If interleaved over more than 1 channel: */
753 		if (intlv_num_chan) {
754 			die_id_bit = intlv_num_chan;
755 			cs_mask	   = (1 << die_id_bit) - 1;
756 			cs_id	   = cs_fabric_id & cs_mask;
757 		}
758 
759 		sock_id_bit = die_id_bit;
760 
761 		/* Read D18F1x208 (SystemFabricIdMask). */
762 		if (intlv_num_dies || intlv_num_sockets)
763 			if (amd_df_indirect_read(nid, 1, 0x208, umc, &tmp))
764 				goto out_err;
765 
766 		/* If interleaved over more than 1 die. */
767 		if (intlv_num_dies) {
768 			sock_id_bit  = die_id_bit + intlv_num_dies;
769 			die_id_shift = (tmp >> 24) & 0xF;
770 			die_id_mask  = (tmp >> 8) & 0xFF;
771 
772 			cs_id |= ((cs_fabric_id & die_id_mask) >> die_id_shift) << die_id_bit;
773 		}
774 
775 		/* If interleaved over more than 1 socket. */
776 		if (intlv_num_sockets) {
777 			socket_id_shift	= (tmp >> 28) & 0xF;
778 			socket_id_mask	= (tmp >> 16) & 0xFF;
779 
780 			cs_id |= ((cs_fabric_id & socket_id_mask) >> socket_id_shift) << sock_id_bit;
781 		}
782 
783 		/*
784 		 * The pre-interleaved address consists of XXXXXXIIIYYYYY
785 		 * where III is the ID for this CS, and XXXXXXYYYYY are the
786 		 * address bits from the post-interleaved address.
787 		 * "num_intlv_bits" has been calculated to tell us how many "I"
788 		 * bits there are. "intlv_addr_bit" tells us how many "Y" bits
789 		 * there are (where "I" starts).
790 		 */
791 		temp_addr_y = ret_addr & GENMASK_ULL(intlv_addr_bit-1, 0);
792 		temp_addr_i = (cs_id << intlv_addr_bit);
793 		temp_addr_x = (ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits;
794 		ret_addr    = temp_addr_x | temp_addr_i | temp_addr_y;
795 	}
796 
797 	/* Add dram base address */
798 	ret_addr += dram_base_addr;
799 
800 	/* If legacy MMIO hole enabled */
801 	if (lgcy_mmio_hole_en) {
802 		if (amd_df_indirect_read(nid, 0, 0x104, umc, &tmp))
803 			goto out_err;
804 
805 		dram_hole_base = tmp & GENMASK(31, 24);
806 		if (ret_addr >= dram_hole_base)
807 			ret_addr += (BIT_ULL(32) - dram_hole_base);
808 	}
809 
810 	if (hash_enabled) {
811 		/* Save some parentheses and grab ls-bit at the end. */
812 		hashed_bit =	(ret_addr >> 12) ^
813 				(ret_addr >> 18) ^
814 				(ret_addr >> 21) ^
815 				(ret_addr >> 30) ^
816 				cs_id;
817 
818 		hashed_bit &= BIT(0);
819 
820 		if (hashed_bit != ((ret_addr >> intlv_addr_bit) & BIT(0)))
821 			ret_addr ^= BIT(intlv_addr_bit);
822 	}
823 
824 	/* Is calculated system address is above DRAM limit address? */
825 	if (ret_addr > dram_limit_addr)
826 		goto out_err;
827 
828 	*sys_addr = ret_addr;
829 	return 0;
830 
831 out_err:
832 	return -EINVAL;
833 }
834 EXPORT_SYMBOL_GPL(umc_normaddr_to_sysaddr);
835 
836 bool amd_mce_is_memory_error(struct mce *m)
837 {
838 	/* ErrCodeExt[20:16] */
839 	u8 xec = (m->status >> 16) & 0x1f;
840 
841 	if (mce_flags.smca)
842 		return smca_get_bank_type(m->bank) == SMCA_UMC && xec == 0x0;
843 
844 	return m->bank == 4 && xec == 0x8;
845 }
846 
847 static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
848 {
849 	struct mce m;
850 
851 	mce_setup(&m);
852 
853 	m.status = status;
854 	m.misc   = misc;
855 	m.bank   = bank;
856 	m.tsc	 = rdtsc();
857 
858 	if (m.status & MCI_STATUS_ADDRV) {
859 		m.addr = addr;
860 
861 		/*
862 		 * Extract [55:<lsb>] where lsb is the least significant
863 		 * *valid* bit of the address bits.
864 		 */
865 		if (mce_flags.smca) {
866 			u8 lsb = (m.addr >> 56) & 0x3f;
867 
868 			m.addr &= GENMASK_ULL(55, lsb);
869 		}
870 	}
871 
872 	if (mce_flags.smca) {
873 		rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
874 
875 		if (m.status & MCI_STATUS_SYNDV)
876 			rdmsrl(MSR_AMD64_SMCA_MCx_SYND(bank), m.synd);
877 	}
878 
879 	mce_log(&m);
880 }
881 
882 asmlinkage __visible void __irq_entry smp_deferred_error_interrupt(struct pt_regs *regs)
883 {
884 	entering_irq();
885 	trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
886 	inc_irq_stat(irq_deferred_error_count);
887 	deferred_error_int_vector();
888 	trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
889 	exiting_ack_irq();
890 }
891 
892 /*
893  * Returns true if the logged error is deferred. False, otherwise.
894  */
895 static inline bool
896 _log_error_bank(unsigned int bank, u32 msr_stat, u32 msr_addr, u64 misc)
897 {
898 	u64 status, addr = 0;
899 
900 	rdmsrl(msr_stat, status);
901 	if (!(status & MCI_STATUS_VAL))
902 		return false;
903 
904 	if (status & MCI_STATUS_ADDRV)
905 		rdmsrl(msr_addr, addr);
906 
907 	__log_error(bank, status, addr, misc);
908 
909 	wrmsrl(msr_stat, 0);
910 
911 	return status & MCI_STATUS_DEFERRED;
912 }
913 
914 /*
915  * We have three scenarios for checking for Deferred errors:
916  *
917  * 1) Non-SMCA systems check MCA_STATUS and log error if found.
918  * 2) SMCA systems check MCA_STATUS. If error is found then log it and also
919  *    clear MCA_DESTAT.
920  * 3) SMCA systems check MCA_DESTAT, if error was not found in MCA_STATUS, and
921  *    log it.
922  */
923 static void log_error_deferred(unsigned int bank)
924 {
925 	bool defrd;
926 
927 	defrd = _log_error_bank(bank, msr_ops.status(bank),
928 					msr_ops.addr(bank), 0);
929 
930 	if (!mce_flags.smca)
931 		return;
932 
933 	/* Clear MCA_DESTAT if we logged the deferred error from MCA_STATUS. */
934 	if (defrd) {
935 		wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(bank), 0);
936 		return;
937 	}
938 
939 	/*
940 	 * Only deferred errors are logged in MCA_DE{STAT,ADDR} so just check
941 	 * for a valid error.
942 	 */
943 	_log_error_bank(bank, MSR_AMD64_SMCA_MCx_DESTAT(bank),
944 			      MSR_AMD64_SMCA_MCx_DEADDR(bank), 0);
945 }
946 
947 /* APIC interrupt handler for deferred errors */
948 static void amd_deferred_error_interrupt(void)
949 {
950 	unsigned int bank;
951 
952 	for (bank = 0; bank < mca_cfg.banks; ++bank)
953 		log_error_deferred(bank);
954 }
955 
956 static void log_error_thresholding(unsigned int bank, u64 misc)
957 {
958 	_log_error_bank(bank, msr_ops.status(bank), msr_ops.addr(bank), misc);
959 }
960 
961 static void log_and_reset_block(struct threshold_block *block)
962 {
963 	struct thresh_restart tr;
964 	u32 low = 0, high = 0;
965 
966 	if (!block)
967 		return;
968 
969 	if (rdmsr_safe(block->address, &low, &high))
970 		return;
971 
972 	if (!(high & MASK_OVERFLOW_HI))
973 		return;
974 
975 	/* Log the MCE which caused the threshold event. */
976 	log_error_thresholding(block->bank, ((u64)high << 32) | low);
977 
978 	/* Reset threshold block after logging error. */
979 	memset(&tr, 0, sizeof(tr));
980 	tr.b = block;
981 	threshold_restart_bank(&tr);
982 }
983 
984 /*
985  * Threshold interrupt handler will service THRESHOLD_APIC_VECTOR. The interrupt
986  * goes off when error_count reaches threshold_limit.
987  */
988 static void amd_threshold_interrupt(void)
989 {
990 	struct threshold_block *first_block = NULL, *block = NULL, *tmp = NULL;
991 	unsigned int bank, cpu = smp_processor_id();
992 
993 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
994 		if (!(per_cpu(bank_map, cpu) & (1 << bank)))
995 			continue;
996 
997 		first_block = per_cpu(threshold_banks, cpu)[bank]->blocks;
998 		if (!first_block)
999 			continue;
1000 
1001 		/*
1002 		 * The first block is also the head of the list. Check it first
1003 		 * before iterating over the rest.
1004 		 */
1005 		log_and_reset_block(first_block);
1006 		list_for_each_entry_safe(block, tmp, &first_block->miscj, miscj)
1007 			log_and_reset_block(block);
1008 	}
1009 }
1010 
1011 /*
1012  * Sysfs Interface
1013  */
1014 
1015 struct threshold_attr {
1016 	struct attribute attr;
1017 	ssize_t (*show) (struct threshold_block *, char *);
1018 	ssize_t (*store) (struct threshold_block *, const char *, size_t count);
1019 };
1020 
1021 #define SHOW_FIELDS(name)						\
1022 static ssize_t show_ ## name(struct threshold_block *b, char *buf)	\
1023 {									\
1024 	return sprintf(buf, "%lu\n", (unsigned long) b->name);		\
1025 }
1026 SHOW_FIELDS(interrupt_enable)
1027 SHOW_FIELDS(threshold_limit)
1028 
1029 static ssize_t
1030 store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
1031 {
1032 	struct thresh_restart tr;
1033 	unsigned long new;
1034 
1035 	if (!b->interrupt_capable)
1036 		return -EINVAL;
1037 
1038 	if (kstrtoul(buf, 0, &new) < 0)
1039 		return -EINVAL;
1040 
1041 	b->interrupt_enable = !!new;
1042 
1043 	memset(&tr, 0, sizeof(tr));
1044 	tr.b		= b;
1045 
1046 	smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
1047 
1048 	return size;
1049 }
1050 
1051 static ssize_t
1052 store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
1053 {
1054 	struct thresh_restart tr;
1055 	unsigned long new;
1056 
1057 	if (kstrtoul(buf, 0, &new) < 0)
1058 		return -EINVAL;
1059 
1060 	if (new > THRESHOLD_MAX)
1061 		new = THRESHOLD_MAX;
1062 	if (new < 1)
1063 		new = 1;
1064 
1065 	memset(&tr, 0, sizeof(tr));
1066 	tr.old_limit = b->threshold_limit;
1067 	b->threshold_limit = new;
1068 	tr.b = b;
1069 
1070 	smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
1071 
1072 	return size;
1073 }
1074 
1075 static ssize_t show_error_count(struct threshold_block *b, char *buf)
1076 {
1077 	u32 lo, hi;
1078 
1079 	rdmsr_on_cpu(b->cpu, b->address, &lo, &hi);
1080 
1081 	return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
1082 				     (THRESHOLD_MAX - b->threshold_limit)));
1083 }
1084 
1085 static struct threshold_attr error_count = {
1086 	.attr = {.name = __stringify(error_count), .mode = 0444 },
1087 	.show = show_error_count,
1088 };
1089 
1090 #define RW_ATTR(val)							\
1091 static struct threshold_attr val = {					\
1092 	.attr	= {.name = __stringify(val), .mode = 0644 },		\
1093 	.show	= show_## val,						\
1094 	.store	= store_## val,						\
1095 };
1096 
1097 RW_ATTR(interrupt_enable);
1098 RW_ATTR(threshold_limit);
1099 
1100 static struct attribute *default_attrs[] = {
1101 	&threshold_limit.attr,
1102 	&error_count.attr,
1103 	NULL,	/* possibly interrupt_enable if supported, see below */
1104 	NULL,
1105 };
1106 
1107 #define to_block(k)	container_of(k, struct threshold_block, kobj)
1108 #define to_attr(a)	container_of(a, struct threshold_attr, attr)
1109 
1110 static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
1111 {
1112 	struct threshold_block *b = to_block(kobj);
1113 	struct threshold_attr *a = to_attr(attr);
1114 	ssize_t ret;
1115 
1116 	ret = a->show ? a->show(b, buf) : -EIO;
1117 
1118 	return ret;
1119 }
1120 
1121 static ssize_t store(struct kobject *kobj, struct attribute *attr,
1122 		     const char *buf, size_t count)
1123 {
1124 	struct threshold_block *b = to_block(kobj);
1125 	struct threshold_attr *a = to_attr(attr);
1126 	ssize_t ret;
1127 
1128 	ret = a->store ? a->store(b, buf, count) : -EIO;
1129 
1130 	return ret;
1131 }
1132 
1133 static const struct sysfs_ops threshold_ops = {
1134 	.show			= show,
1135 	.store			= store,
1136 };
1137 
1138 static struct kobj_type threshold_ktype = {
1139 	.sysfs_ops		= &threshold_ops,
1140 	.default_attrs		= default_attrs,
1141 };
1142 
1143 static const char *get_name(unsigned int bank, struct threshold_block *b)
1144 {
1145 	enum smca_bank_types bank_type;
1146 
1147 	if (!mce_flags.smca) {
1148 		if (b && bank == 4)
1149 			return bank4_names(b);
1150 
1151 		return th_names[bank];
1152 	}
1153 
1154 	bank_type = smca_get_bank_type(bank);
1155 	if (bank_type >= N_SMCA_BANK_TYPES)
1156 		return NULL;
1157 
1158 	if (b && bank_type == SMCA_UMC) {
1159 		if (b->block < ARRAY_SIZE(smca_umc_block_names))
1160 			return smca_umc_block_names[b->block];
1161 		return NULL;
1162 	}
1163 
1164 	if (smca_banks[bank].hwid->count == 1)
1165 		return smca_get_name(bank_type);
1166 
1167 	snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
1168 		 "%s_%x", smca_get_name(bank_type),
1169 			  smca_banks[bank].sysfs_id);
1170 	return buf_mcatype;
1171 }
1172 
1173 static int allocate_threshold_blocks(unsigned int cpu, unsigned int bank,
1174 				     unsigned int block, u32 address)
1175 {
1176 	struct threshold_block *b = NULL;
1177 	u32 low, high;
1178 	int err;
1179 
1180 	if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
1181 		return 0;
1182 
1183 	if (rdmsr_safe_on_cpu(cpu, address, &low, &high))
1184 		return 0;
1185 
1186 	if (!(high & MASK_VALID_HI)) {
1187 		if (block)
1188 			goto recurse;
1189 		else
1190 			return 0;
1191 	}
1192 
1193 	if (!(high & MASK_CNTP_HI)  ||
1194 	     (high & MASK_LOCKED_HI))
1195 		goto recurse;
1196 
1197 	b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
1198 	if (!b)
1199 		return -ENOMEM;
1200 
1201 	b->block		= block;
1202 	b->bank			= bank;
1203 	b->cpu			= cpu;
1204 	b->address		= address;
1205 	b->interrupt_enable	= 0;
1206 	b->interrupt_capable	= lvt_interrupt_supported(bank, high);
1207 	b->threshold_limit	= THRESHOLD_MAX;
1208 
1209 	if (b->interrupt_capable) {
1210 		threshold_ktype.default_attrs[2] = &interrupt_enable.attr;
1211 		b->interrupt_enable = 1;
1212 	} else {
1213 		threshold_ktype.default_attrs[2] = NULL;
1214 	}
1215 
1216 	INIT_LIST_HEAD(&b->miscj);
1217 
1218 	if (per_cpu(threshold_banks, cpu)[bank]->blocks) {
1219 		list_add(&b->miscj,
1220 			 &per_cpu(threshold_banks, cpu)[bank]->blocks->miscj);
1221 	} else {
1222 		per_cpu(threshold_banks, cpu)[bank]->blocks = b;
1223 	}
1224 
1225 	err = kobject_init_and_add(&b->kobj, &threshold_ktype,
1226 				   per_cpu(threshold_banks, cpu)[bank]->kobj,
1227 				   get_name(bank, b));
1228 	if (err)
1229 		goto out_free;
1230 recurse:
1231 	address = get_block_address(address, low, high, bank, ++block);
1232 	if (!address)
1233 		return 0;
1234 
1235 	err = allocate_threshold_blocks(cpu, bank, block, address);
1236 	if (err)
1237 		goto out_free;
1238 
1239 	if (b)
1240 		kobject_uevent(&b->kobj, KOBJ_ADD);
1241 
1242 	return err;
1243 
1244 out_free:
1245 	if (b) {
1246 		kobject_put(&b->kobj);
1247 		list_del(&b->miscj);
1248 		kfree(b);
1249 	}
1250 	return err;
1251 }
1252 
1253 static int __threshold_add_blocks(struct threshold_bank *b)
1254 {
1255 	struct list_head *head = &b->blocks->miscj;
1256 	struct threshold_block *pos = NULL;
1257 	struct threshold_block *tmp = NULL;
1258 	int err = 0;
1259 
1260 	err = kobject_add(&b->blocks->kobj, b->kobj, b->blocks->kobj.name);
1261 	if (err)
1262 		return err;
1263 
1264 	list_for_each_entry_safe(pos, tmp, head, miscj) {
1265 
1266 		err = kobject_add(&pos->kobj, b->kobj, pos->kobj.name);
1267 		if (err) {
1268 			list_for_each_entry_safe_reverse(pos, tmp, head, miscj)
1269 				kobject_del(&pos->kobj);
1270 
1271 			return err;
1272 		}
1273 	}
1274 	return err;
1275 }
1276 
1277 static int threshold_create_bank(unsigned int cpu, unsigned int bank)
1278 {
1279 	struct device *dev = per_cpu(mce_device, cpu);
1280 	struct amd_northbridge *nb = NULL;
1281 	struct threshold_bank *b = NULL;
1282 	const char *name = get_name(bank, NULL);
1283 	int err = 0;
1284 
1285 	if (!dev)
1286 		return -ENODEV;
1287 
1288 	if (is_shared_bank(bank)) {
1289 		nb = node_to_amd_nb(amd_get_nb_id(cpu));
1290 
1291 		/* threshold descriptor already initialized on this node? */
1292 		if (nb && nb->bank4) {
1293 			/* yes, use it */
1294 			b = nb->bank4;
1295 			err = kobject_add(b->kobj, &dev->kobj, name);
1296 			if (err)
1297 				goto out;
1298 
1299 			per_cpu(threshold_banks, cpu)[bank] = b;
1300 			refcount_inc(&b->cpus);
1301 
1302 			err = __threshold_add_blocks(b);
1303 
1304 			goto out;
1305 		}
1306 	}
1307 
1308 	b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
1309 	if (!b) {
1310 		err = -ENOMEM;
1311 		goto out;
1312 	}
1313 
1314 	b->kobj = kobject_create_and_add(name, &dev->kobj);
1315 	if (!b->kobj) {
1316 		err = -EINVAL;
1317 		goto out_free;
1318 	}
1319 
1320 	per_cpu(threshold_banks, cpu)[bank] = b;
1321 
1322 	if (is_shared_bank(bank)) {
1323 		refcount_set(&b->cpus, 1);
1324 
1325 		/* nb is already initialized, see above */
1326 		if (nb) {
1327 			WARN_ON(nb->bank4);
1328 			nb->bank4 = b;
1329 		}
1330 	}
1331 
1332 	err = allocate_threshold_blocks(cpu, bank, 0, msr_ops.misc(bank));
1333 	if (!err)
1334 		goto out;
1335 
1336  out_free:
1337 	kfree(b);
1338 
1339  out:
1340 	return err;
1341 }
1342 
1343 static void deallocate_threshold_block(unsigned int cpu,
1344 						 unsigned int bank)
1345 {
1346 	struct threshold_block *pos = NULL;
1347 	struct threshold_block *tmp = NULL;
1348 	struct threshold_bank *head = per_cpu(threshold_banks, cpu)[bank];
1349 
1350 	if (!head)
1351 		return;
1352 
1353 	list_for_each_entry_safe(pos, tmp, &head->blocks->miscj, miscj) {
1354 		kobject_put(&pos->kobj);
1355 		list_del(&pos->miscj);
1356 		kfree(pos);
1357 	}
1358 
1359 	kfree(per_cpu(threshold_banks, cpu)[bank]->blocks);
1360 	per_cpu(threshold_banks, cpu)[bank]->blocks = NULL;
1361 }
1362 
1363 static void __threshold_remove_blocks(struct threshold_bank *b)
1364 {
1365 	struct threshold_block *pos = NULL;
1366 	struct threshold_block *tmp = NULL;
1367 
1368 	kobject_del(b->kobj);
1369 
1370 	list_for_each_entry_safe(pos, tmp, &b->blocks->miscj, miscj)
1371 		kobject_del(&pos->kobj);
1372 }
1373 
1374 static void threshold_remove_bank(unsigned int cpu, int bank)
1375 {
1376 	struct amd_northbridge *nb;
1377 	struct threshold_bank *b;
1378 
1379 	b = per_cpu(threshold_banks, cpu)[bank];
1380 	if (!b)
1381 		return;
1382 
1383 	if (!b->blocks)
1384 		goto free_out;
1385 
1386 	if (is_shared_bank(bank)) {
1387 		if (!refcount_dec_and_test(&b->cpus)) {
1388 			__threshold_remove_blocks(b);
1389 			per_cpu(threshold_banks, cpu)[bank] = NULL;
1390 			return;
1391 		} else {
1392 			/*
1393 			 * the last CPU on this node using the shared bank is
1394 			 * going away, remove that bank now.
1395 			 */
1396 			nb = node_to_amd_nb(amd_get_nb_id(cpu));
1397 			nb->bank4 = NULL;
1398 		}
1399 	}
1400 
1401 	deallocate_threshold_block(cpu, bank);
1402 
1403 free_out:
1404 	kobject_del(b->kobj);
1405 	kobject_put(b->kobj);
1406 	kfree(b);
1407 	per_cpu(threshold_banks, cpu)[bank] = NULL;
1408 }
1409 
1410 int mce_threshold_remove_device(unsigned int cpu)
1411 {
1412 	unsigned int bank;
1413 
1414 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
1415 		if (!(per_cpu(bank_map, cpu) & (1 << bank)))
1416 			continue;
1417 		threshold_remove_bank(cpu, bank);
1418 	}
1419 	kfree(per_cpu(threshold_banks, cpu));
1420 	per_cpu(threshold_banks, cpu) = NULL;
1421 	return 0;
1422 }
1423 
1424 /* create dir/files for all valid threshold banks */
1425 int mce_threshold_create_device(unsigned int cpu)
1426 {
1427 	unsigned int bank;
1428 	struct threshold_bank **bp;
1429 	int err = 0;
1430 
1431 	bp = per_cpu(threshold_banks, cpu);
1432 	if (bp)
1433 		return 0;
1434 
1435 	bp = kcalloc(mca_cfg.banks, sizeof(struct threshold_bank *),
1436 		     GFP_KERNEL);
1437 	if (!bp)
1438 		return -ENOMEM;
1439 
1440 	per_cpu(threshold_banks, cpu) = bp;
1441 
1442 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
1443 		if (!(per_cpu(bank_map, cpu) & (1 << bank)))
1444 			continue;
1445 		err = threshold_create_bank(cpu, bank);
1446 		if (err)
1447 			goto err;
1448 	}
1449 	return err;
1450 err:
1451 	mce_threshold_remove_device(cpu);
1452 	return err;
1453 }
1454 
1455 static __init int threshold_init_device(void)
1456 {
1457 	unsigned lcpu = 0;
1458 
1459 	/* to hit CPUs online before the notifier is up */
1460 	for_each_online_cpu(lcpu) {
1461 		int err = mce_threshold_create_device(lcpu);
1462 
1463 		if (err)
1464 			return err;
1465 	}
1466 
1467 	if (thresholding_irq_en)
1468 		mce_threshold_vector = amd_threshold_interrupt;
1469 
1470 	return 0;
1471 }
1472 /*
1473  * there are 3 funcs which need to be _initcalled in a logic sequence:
1474  * 1. xen_late_init_mcelog
1475  * 2. mcheck_init_device
1476  * 3. threshold_init_device
1477  *
1478  * xen_late_init_mcelog must register xen_mce_chrdev_device before
1479  * native mce_chrdev_device registration if running under xen platform;
1480  *
1481  * mcheck_init_device should be inited before threshold_init_device to
1482  * initialize mce_device, otherwise a NULL ptr dereference will cause panic.
1483  *
1484  * so we use following _initcalls
1485  * 1. device_initcall(xen_late_init_mcelog);
1486  * 2. device_initcall_sync(mcheck_init_device);
1487  * 3. late_initcall(threshold_init_device);
1488  *
1489  * when running under xen, the initcall order is 1,2,3;
1490  * on baremetal, we skip 1 and we do only 2 and 3.
1491  */
1492 late_initcall(threshold_init_device);
1493