1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  (c) 2005-2016 Advanced Micro Devices, Inc.
4 *
5 *  Written by Jacob Shin - AMD, Inc.
6 *  Maintained by: Borislav Petkov <bp@alien8.de>
7 *
8 *  All MC4_MISCi registers are shared between cores on a node.
9 */
10#include <linux/interrupt.h>
11#include <linux/notifier.h>
12#include <linux/kobject.h>
13#include <linux/percpu.h>
14#include <linux/errno.h>
15#include <linux/sched.h>
16#include <linux/sysfs.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/cpu.h>
20#include <linux/smp.h>
21#include <linux/string.h>
22
23#include <asm/amd_nb.h>
24#include <asm/traps.h>
25#include <asm/apic.h>
26#include <asm/mce.h>
27#include <asm/msr.h>
28#include <asm/trace/irq_vectors.h>
29
30#include "internal.h"
31
32#define NR_BLOCKS         5
33#define THRESHOLD_MAX     0xFFF
34#define INT_TYPE_APIC     0x00020000
35#define MASK_VALID_HI     0x80000000
36#define MASK_CNTP_HI      0x40000000
37#define MASK_LOCKED_HI    0x20000000
38#define MASK_LVTOFF_HI    0x00F00000
39#define MASK_COUNT_EN_HI  0x00080000
40#define MASK_INT_TYPE_HI  0x00060000
41#define MASK_OVERFLOW_HI  0x00010000
42#define MASK_ERR_COUNT_HI 0x00000FFF
43#define MASK_BLKPTR_LO    0xFF000000
44#define MCG_XBLK_ADDR     0xC0000400
45
46/* Deferred error settings */
47#define MSR_CU_DEF_ERR		0xC0000410
48#define MASK_DEF_LVTOFF		0x000000F0
49#define MASK_DEF_INT_TYPE	0x00000006
50#define DEF_LVT_OFF		0x2
51#define DEF_INT_TYPE_APIC	0x2
52
53/* Scalable MCA: */
54
55/* Threshold LVT offset is at MSR0xC0000410[15:12] */
56#define SMCA_THR_LVT_OFF	0xF000
57
58static bool thresholding_irq_en;
59
60static const char * const th_names[] = {
61	"load_store",
62	"insn_fetch",
63	"combined_unit",
64	"decode_unit",
65	"northbridge",
66	"execution_unit",
67};
68
69static const char * const smca_umc_block_names[] = {
70	"dram_ecc",
71	"misc_umc"
72};
73
74#define HWID_MCATYPE(hwid, mcatype) (((hwid) << 16) | (mcatype))
75
76struct smca_hwid {
77	unsigned int bank_type;	/* Use with smca_bank_types for easy indexing. */
78	u32 hwid_mcatype;	/* (hwid,mcatype) tuple */
79};
80
81struct smca_bank {
82	const struct smca_hwid *hwid;
83	u32 id;			/* Value of MCA_IPID[InstanceId]. */
84	u8 sysfs_id;		/* Value used for sysfs name. */
85};
86
87static DEFINE_PER_CPU_READ_MOSTLY(struct smca_bank[MAX_NR_BANKS], smca_banks);
88static DEFINE_PER_CPU_READ_MOSTLY(u8[N_SMCA_BANK_TYPES], smca_bank_counts);
89
90static const char * const smca_names[] = {
91	[SMCA_LS ... SMCA_LS_V2]	= "load_store",
92	[SMCA_IF]			= "insn_fetch",
93	[SMCA_L2_CACHE]			= "l2_cache",
94	[SMCA_DE]			= "decode_unit",
95	[SMCA_RESERVED]			= "reserved",
96	[SMCA_EX]			= "execution_unit",
97	[SMCA_FP]			= "floating_point",
98	[SMCA_L3_CACHE]			= "l3_cache",
99	[SMCA_CS ... SMCA_CS_V2]	= "coherent_slave",
100	[SMCA_PIE]			= "pie",
101
102	/* UMC v2 is separate because both of them can exist in a single system. */
103	[SMCA_UMC]			= "umc",
104	[SMCA_UMC_V2]			= "umc_v2",
105	[SMCA_MA_LLC]			= "ma_llc",
106	[SMCA_PB]			= "param_block",
107	[SMCA_PSP ... SMCA_PSP_V2]	= "psp",
108	[SMCA_SMU ... SMCA_SMU_V2]	= "smu",
109	[SMCA_MP5]			= "mp5",
110	[SMCA_MPDMA]			= "mpdma",
111	[SMCA_NBIO]			= "nbio",
112	[SMCA_PCIE ... SMCA_PCIE_V2]	= "pcie",
113	[SMCA_XGMI_PCS]			= "xgmi_pcs",
114	[SMCA_NBIF]			= "nbif",
115	[SMCA_SHUB]			= "shub",
116	[SMCA_SATA]			= "sata",
117	[SMCA_USB]			= "usb",
118	[SMCA_USR_DP]			= "usr_dp",
119	[SMCA_USR_CP]			= "usr_cp",
120	[SMCA_GMI_PCS]			= "gmi_pcs",
121	[SMCA_XGMI_PHY]			= "xgmi_phy",
122	[SMCA_WAFL_PHY]			= "wafl_phy",
123	[SMCA_GMI_PHY]			= "gmi_phy",
124};
125
126static const char *smca_get_name(enum smca_bank_types t)
127{
128	if (t >= N_SMCA_BANK_TYPES)
129		return NULL;
130
131	return smca_names[t];
132}
133
134enum smca_bank_types smca_get_bank_type(unsigned int cpu, unsigned int bank)
135{
136	struct smca_bank *b;
137
138	if (bank >= MAX_NR_BANKS)
139		return N_SMCA_BANK_TYPES;
140
141	b = &per_cpu(smca_banks, cpu)[bank];
142	if (!b->hwid)
143		return N_SMCA_BANK_TYPES;
144
145	return b->hwid->bank_type;
146}
147EXPORT_SYMBOL_GPL(smca_get_bank_type);
148
149static const struct smca_hwid smca_hwid_mcatypes[] = {
150	/* { bank_type, hwid_mcatype } */
151
152	/* Reserved type */
153	{ SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0)	},
154
155	/* ZN Core (HWID=0xB0) MCA types */
156	{ SMCA_LS,	 HWID_MCATYPE(0xB0, 0x0)	},
157	{ SMCA_LS_V2,	 HWID_MCATYPE(0xB0, 0x10)	},
158	{ SMCA_IF,	 HWID_MCATYPE(0xB0, 0x1)	},
159	{ SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2)	},
160	{ SMCA_DE,	 HWID_MCATYPE(0xB0, 0x3)	},
161	/* HWID 0xB0 MCATYPE 0x4 is Reserved */
162	{ SMCA_EX,	 HWID_MCATYPE(0xB0, 0x5)	},
163	{ SMCA_FP,	 HWID_MCATYPE(0xB0, 0x6)	},
164	{ SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7)	},
165
166	/* Data Fabric MCA types */
167	{ SMCA_CS,	 HWID_MCATYPE(0x2E, 0x0)	},
168	{ SMCA_PIE,	 HWID_MCATYPE(0x2E, 0x1)	},
169	{ SMCA_CS_V2,	 HWID_MCATYPE(0x2E, 0x2)	},
170	{ SMCA_MA_LLC,	 HWID_MCATYPE(0x2E, 0x4)	},
171
172	/* Unified Memory Controller MCA type */
173	{ SMCA_UMC,	 HWID_MCATYPE(0x96, 0x0)	},
174	{ SMCA_UMC_V2,	 HWID_MCATYPE(0x96, 0x1)	},
175
176	/* Parameter Block MCA type */
177	{ SMCA_PB,	 HWID_MCATYPE(0x05, 0x0)	},
178
179	/* Platform Security Processor MCA type */
180	{ SMCA_PSP,	 HWID_MCATYPE(0xFF, 0x0)	},
181	{ SMCA_PSP_V2,	 HWID_MCATYPE(0xFF, 0x1)	},
182
183	/* System Management Unit MCA type */
184	{ SMCA_SMU,	 HWID_MCATYPE(0x01, 0x0)	},
185	{ SMCA_SMU_V2,	 HWID_MCATYPE(0x01, 0x1)	},
186
187	/* Microprocessor 5 Unit MCA type */
188	{ SMCA_MP5,	 HWID_MCATYPE(0x01, 0x2)	},
189
190	/* MPDMA MCA type */
191	{ SMCA_MPDMA,	 HWID_MCATYPE(0x01, 0x3)	},
192
193	/* Northbridge IO Unit MCA type */
194	{ SMCA_NBIO,	 HWID_MCATYPE(0x18, 0x0)	},
195
196	/* PCI Express Unit MCA type */
197	{ SMCA_PCIE,	 HWID_MCATYPE(0x46, 0x0)	},
198	{ SMCA_PCIE_V2,	 HWID_MCATYPE(0x46, 0x1)	},
199
200	{ SMCA_XGMI_PCS, HWID_MCATYPE(0x50, 0x0)	},
201	{ SMCA_NBIF,	 HWID_MCATYPE(0x6C, 0x0)	},
202	{ SMCA_SHUB,	 HWID_MCATYPE(0x80, 0x0)	},
203	{ SMCA_SATA,	 HWID_MCATYPE(0xA8, 0x0)	},
204	{ SMCA_USB,	 HWID_MCATYPE(0xAA, 0x0)	},
205	{ SMCA_USR_DP,	 HWID_MCATYPE(0x170, 0x0)	},
206	{ SMCA_USR_CP,	 HWID_MCATYPE(0x180, 0x0)	},
207	{ SMCA_GMI_PCS,  HWID_MCATYPE(0x241, 0x0)	},
208	{ SMCA_XGMI_PHY, HWID_MCATYPE(0x259, 0x0)	},
209	{ SMCA_WAFL_PHY, HWID_MCATYPE(0x267, 0x0)	},
210	{ SMCA_GMI_PHY,	 HWID_MCATYPE(0x269, 0x0)	},
211};
212
213/*
214 * In SMCA enabled processors, we can have multiple banks for a given IP type.
215 * So to define a unique name for each bank, we use a temp c-string to append
216 * the MCA_IPID[InstanceId] to type's name in get_name().
217 *
218 * InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
219 * is greater than 8 plus 1 (for underscore) plus length of longest type name.
220 */
221#define MAX_MCATYPE_NAME_LEN	30
222static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
223
224static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
225
226/*
227 * A list of the banks enabled on each logical CPU. Controls which respective
228 * descriptors to initialize later in mce_threshold_create_device().
229 */
230static DEFINE_PER_CPU(u64, bank_map);
231
232/* Map of banks that have more than MCA_MISC0 available. */
233static DEFINE_PER_CPU(u64, smca_misc_banks_map);
234
235static void amd_threshold_interrupt(void);
236static void amd_deferred_error_interrupt(void);
237
238static void default_deferred_error_interrupt(void)
239{
240	pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
241}
242void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
243
244static void smca_set_misc_banks_map(unsigned int bank, unsigned int cpu)
245{
246	u32 low, high;
247
248	/*
249	 * For SMCA enabled processors, BLKPTR field of the first MISC register
250	 * (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
251	 */
252	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
253		return;
254
255	if (!(low & MCI_CONFIG_MCAX))
256		return;
257
258	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high))
259		return;
260
261	if (low & MASK_BLKPTR_LO)
262		per_cpu(smca_misc_banks_map, cpu) |= BIT_ULL(bank);
263
264}
265
266static void smca_configure(unsigned int bank, unsigned int cpu)
267{
268	u8 *bank_counts = this_cpu_ptr(smca_bank_counts);
269	const struct smca_hwid *s_hwid;
270	unsigned int i, hwid_mcatype;
271	u32 high, low;
272	u32 smca_config = MSR_AMD64_SMCA_MCx_CONFIG(bank);
273
274	/* Set appropriate bits in MCA_CONFIG */
275	if (!rdmsr_safe(smca_config, &low, &high)) {
276		/*
277		 * OS is required to set the MCAX bit to acknowledge that it is
278		 * now using the new MSR ranges and new registers under each
279		 * bank. It also means that the OS will configure deferred
280		 * errors in the new MCx_CONFIG register. If the bit is not set,
281		 * uncorrectable errors will cause a system panic.
282		 *
283		 * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
284		 */
285		high |= BIT(0);
286
287		/*
288		 * SMCA sets the Deferred Error Interrupt type per bank.
289		 *
290		 * MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
291		 * if the DeferredIntType bit field is available.
292		 *
293		 * MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
294		 * high portion of the MSR). OS should set this to 0x1 to enable
295		 * APIC based interrupt. First, check that no interrupt has been
296		 * set.
297		 */
298		if ((low & BIT(5)) && !((high >> 5) & 0x3))
299			high |= BIT(5);
300
301		this_cpu_ptr(mce_banks_array)[bank].lsb_in_status = !!(low & BIT(8));
302
303		wrmsr(smca_config, low, high);
304	}
305
306	smca_set_misc_banks_map(bank, cpu);
307
308	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
309		pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
310		return;
311	}
312
313	hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
314				    (high & MCI_IPID_MCATYPE) >> 16);
315
316	for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
317		s_hwid = &smca_hwid_mcatypes[i];
318
319		if (hwid_mcatype == s_hwid->hwid_mcatype) {
320			this_cpu_ptr(smca_banks)[bank].hwid = s_hwid;
321			this_cpu_ptr(smca_banks)[bank].id = low;
322			this_cpu_ptr(smca_banks)[bank].sysfs_id = bank_counts[s_hwid->bank_type]++;
323			break;
324		}
325	}
326}
327
328struct thresh_restart {
329	struct threshold_block	*b;
330	int			reset;
331	int			set_lvt_off;
332	int			lvt_off;
333	u16			old_limit;
334};
335
336static inline bool is_shared_bank(int bank)
337{
338	/*
339	 * Scalable MCA provides for only one core to have access to the MSRs of
340	 * a shared bank.
341	 */
342	if (mce_flags.smca)
343		return false;
344
345	/* Bank 4 is for northbridge reporting and is thus shared */
346	return (bank == 4);
347}
348
349static const char *bank4_names(const struct threshold_block *b)
350{
351	switch (b->address) {
352	/* MSR4_MISC0 */
353	case 0x00000413:
354		return "dram";
355
356	case 0xc0000408:
357		return "ht_links";
358
359	case 0xc0000409:
360		return "l3_cache";
361
362	default:
363		WARN(1, "Funny MSR: 0x%08x\n", b->address);
364		return "";
365	}
366};
367
368
369static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
370{
371	/*
372	 * bank 4 supports APIC LVT interrupts implicitly since forever.
373	 */
374	if (bank == 4)
375		return true;
376
377	/*
378	 * IntP: interrupt present; if this bit is set, the thresholding
379	 * bank can generate APIC LVT interrupts
380	 */
381	return msr_high_bits & BIT(28);
382}
383
384static int lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
385{
386	int msr = (hi & MASK_LVTOFF_HI) >> 20;
387
388	if (apic < 0) {
389		pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
390		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
391		       b->bank, b->block, b->address, hi, lo);
392		return 0;
393	}
394
395	if (apic != msr) {
396		/*
397		 * On SMCA CPUs, LVT offset is programmed at a different MSR, and
398		 * the BIOS provides the value. The original field where LVT offset
399		 * was set is reserved. Return early here:
400		 */
401		if (mce_flags.smca)
402			return 0;
403
404		pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
405		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n",
406		       b->cpu, apic, b->bank, b->block, b->address, hi, lo);
407		return 0;
408	}
409
410	return 1;
411};
412
413/* Reprogram MCx_MISC MSR behind this threshold bank. */
414static void threshold_restart_bank(void *_tr)
415{
416	struct thresh_restart *tr = _tr;
417	u32 hi, lo;
418
419	/* sysfs write might race against an offline operation */
420	if (!this_cpu_read(threshold_banks) && !tr->set_lvt_off)
421		return;
422
423	rdmsr(tr->b->address, lo, hi);
424
425	if (tr->b->threshold_limit < (hi & THRESHOLD_MAX))
426		tr->reset = 1;	/* limit cannot be lower than err count */
427
428	if (tr->reset) {		/* reset err count and overflow bit */
429		hi =
430		    (hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
431		    (THRESHOLD_MAX - tr->b->threshold_limit);
432	} else if (tr->old_limit) {	/* change limit w/o reset */
433		int new_count = (hi & THRESHOLD_MAX) +
434		    (tr->old_limit - tr->b->threshold_limit);
435
436		hi = (hi & ~MASK_ERR_COUNT_HI) |
437		    (new_count & THRESHOLD_MAX);
438	}
439
440	/* clear IntType */
441	hi &= ~MASK_INT_TYPE_HI;
442
443	if (!tr->b->interrupt_capable)
444		goto done;
445
446	if (tr->set_lvt_off) {
447		if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
448			/* set new lvt offset */
449			hi &= ~MASK_LVTOFF_HI;
450			hi |= tr->lvt_off << 20;
451		}
452	}
453
454	if (tr->b->interrupt_enable)
455		hi |= INT_TYPE_APIC;
456
457 done:
458
459	hi |= MASK_COUNT_EN_HI;
460	wrmsr(tr->b->address, lo, hi);
461}
462
463static void mce_threshold_block_init(struct threshold_block *b, int offset)
464{
465	struct thresh_restart tr = {
466		.b			= b,
467		.set_lvt_off		= 1,
468		.lvt_off		= offset,
469	};
470
471	b->threshold_limit		= THRESHOLD_MAX;
472	threshold_restart_bank(&tr);
473};
474
475static int setup_APIC_mce_threshold(int reserved, int new)
476{
477	if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
478					      APIC_EILVT_MSG_FIX, 0))
479		return new;
480
481	return reserved;
482}
483
484static int setup_APIC_deferred_error(int reserved, int new)
485{
486	if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
487					      APIC_EILVT_MSG_FIX, 0))
488		return new;
489
490	return reserved;
491}
492
493static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
494{
495	u32 low = 0, high = 0;
496	int def_offset = -1, def_new;
497
498	if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
499		return;
500
501	def_new = (low & MASK_DEF_LVTOFF) >> 4;
502	if (!(low & MASK_DEF_LVTOFF)) {
503		pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
504		def_new = DEF_LVT_OFF;
505		low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
506	}
507
508	def_offset = setup_APIC_deferred_error(def_offset, def_new);
509	if ((def_offset == def_new) &&
510	    (deferred_error_int_vector != amd_deferred_error_interrupt))
511		deferred_error_int_vector = amd_deferred_error_interrupt;
512
513	if (!mce_flags.smca)
514		low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
515
516	wrmsr(MSR_CU_DEF_ERR, low, high);
517}
518
519static u32 smca_get_block_address(unsigned int bank, unsigned int block,
520				  unsigned int cpu)
521{
522	if (!block)
523		return MSR_AMD64_SMCA_MCx_MISC(bank);
524
525	if (!(per_cpu(smca_misc_banks_map, cpu) & BIT_ULL(bank)))
526		return 0;
527
528	return MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
529}
530
531static u32 get_block_address(u32 current_addr, u32 low, u32 high,
532			     unsigned int bank, unsigned int block,
533			     unsigned int cpu)
534{
535	u32 addr = 0, offset = 0;
536
537	if ((bank >= per_cpu(mce_num_banks, cpu)) || (block >= NR_BLOCKS))
538		return addr;
539
540	if (mce_flags.smca)
541		return smca_get_block_address(bank, block, cpu);
542
543	/* Fall back to method we used for older processors: */
544	switch (block) {
545	case 0:
546		addr = mca_msr_reg(bank, MCA_MISC);
547		break;
548	case 1:
549		offset = ((low & MASK_BLKPTR_LO) >> 21);
550		if (offset)
551			addr = MCG_XBLK_ADDR + offset;
552		break;
553	default:
554		addr = ++current_addr;
555	}
556	return addr;
557}
558
559static int
560prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
561			int offset, u32 misc_high)
562{
563	unsigned int cpu = smp_processor_id();
564	u32 smca_low, smca_high;
565	struct threshold_block b;
566	int new;
567
568	if (!block)
569		per_cpu(bank_map, cpu) |= BIT_ULL(bank);
570
571	memset(&b, 0, sizeof(b));
572	b.cpu			= cpu;
573	b.bank			= bank;
574	b.block			= block;
575	b.address		= addr;
576	b.interrupt_capable	= lvt_interrupt_supported(bank, misc_high);
577
578	if (!b.interrupt_capable)
579		goto done;
580
581	b.interrupt_enable = 1;
582
583	if (!mce_flags.smca) {
584		new = (misc_high & MASK_LVTOFF_HI) >> 20;
585		goto set_offset;
586	}
587
588	/* Gather LVT offset for thresholding: */
589	if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
590		goto out;
591
592	new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
593
594set_offset:
595	offset = setup_APIC_mce_threshold(offset, new);
596	if (offset == new)
597		thresholding_irq_en = true;
598
599done:
600	mce_threshold_block_init(&b, offset);
601
602out:
603	return offset;
604}
605
606bool amd_filter_mce(struct mce *m)
607{
608	enum smca_bank_types bank_type = smca_get_bank_type(m->extcpu, m->bank);
609	struct cpuinfo_x86 *c = &boot_cpu_data;
610
611	/* See Family 17h Models 10h-2Fh Erratum #1114. */
612	if (c->x86 == 0x17 &&
613	    c->x86_model >= 0x10 && c->x86_model <= 0x2F &&
614	    bank_type == SMCA_IF && XEC(m->status, 0x3f) == 10)
615		return true;
616
617	/* NB GART TLB error reporting is disabled by default. */
618	if (c->x86 < 0x17) {
619		if (m->bank == 4 && XEC(m->status, 0x1f) == 0x5)
620			return true;
621	}
622
623	return false;
624}
625
626/*
627 * Turn off thresholding banks for the following conditions:
628 * - MC4_MISC thresholding is not supported on Family 0x15.
629 * - Prevent possible spurious interrupts from the IF bank on Family 0x17
630 *   Models 0x10-0x2F due to Erratum #1114.
631 */
632static void disable_err_thresholding(struct cpuinfo_x86 *c, unsigned int bank)
633{
634	int i, num_msrs;
635	u64 hwcr;
636	bool need_toggle;
637	u32 msrs[NR_BLOCKS];
638
639	if (c->x86 == 0x15 && bank == 4) {
640		msrs[0] = 0x00000413; /* MC4_MISC0 */
641		msrs[1] = 0xc0000408; /* MC4_MISC1 */
642		num_msrs = 2;
643	} else if (c->x86 == 0x17 &&
644		   (c->x86_model >= 0x10 && c->x86_model <= 0x2F)) {
645
646		if (smca_get_bank_type(smp_processor_id(), bank) != SMCA_IF)
647			return;
648
649		msrs[0] = MSR_AMD64_SMCA_MCx_MISC(bank);
650		num_msrs = 1;
651	} else {
652		return;
653	}
654
655	rdmsrl(MSR_K7_HWCR, hwcr);
656
657	/* McStatusWrEn has to be set */
658	need_toggle = !(hwcr & BIT(18));
659	if (need_toggle)
660		wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
661
662	/* Clear CntP bit safely */
663	for (i = 0; i < num_msrs; i++)
664		msr_clear_bit(msrs[i], 62);
665
666	/* restore old settings */
667	if (need_toggle)
668		wrmsrl(MSR_K7_HWCR, hwcr);
669}
670
671/* cpu init entry point, called from mce.c with preempt off */
672void mce_amd_feature_init(struct cpuinfo_x86 *c)
673{
674	unsigned int bank, block, cpu = smp_processor_id();
675	u32 low = 0, high = 0, address = 0;
676	int offset = -1;
677
678
679	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
680		if (mce_flags.smca)
681			smca_configure(bank, cpu);
682
683		disable_err_thresholding(c, bank);
684
685		for (block = 0; block < NR_BLOCKS; ++block) {
686			address = get_block_address(address, low, high, bank, block, cpu);
687			if (!address)
688				break;
689
690			if (rdmsr_safe(address, &low, &high))
691				break;
692
693			if (!(high & MASK_VALID_HI))
694				continue;
695
696			if (!(high & MASK_CNTP_HI)  ||
697			     (high & MASK_LOCKED_HI))
698				continue;
699
700			offset = prepare_threshold_block(bank, block, address, offset, high);
701		}
702	}
703
704	if (mce_flags.succor)
705		deferred_error_interrupt_enable(c);
706}
707
708/*
709 * DRAM ECC errors are reported in the Northbridge (bank 4) with
710 * Extended Error Code 8.
711 */
712static bool legacy_mce_is_memory_error(struct mce *m)
713{
714	return m->bank == 4 && XEC(m->status, 0x1f) == 8;
715}
716
717/*
718 * DRAM ECC errors are reported in Unified Memory Controllers with
719 * Extended Error Code 0.
720 */
721static bool smca_mce_is_memory_error(struct mce *m)
722{
723	enum smca_bank_types bank_type;
724
725	if (XEC(m->status, 0x3f))
726		return false;
727
728	bank_type = smca_get_bank_type(m->extcpu, m->bank);
729
730	return bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2;
731}
732
733bool amd_mce_is_memory_error(struct mce *m)
734{
735	if (mce_flags.smca)
736		return smca_mce_is_memory_error(m);
737	else
738		return legacy_mce_is_memory_error(m);
739}
740
741/*
742 * AMD systems do not have an explicit indicator that the value in MCA_ADDR is
743 * a system physical address. Therefore, individual cases need to be detected.
744 * Future cases and checks will be added as needed.
745 *
746 * 1) General case
747 *	a) Assume address is not usable.
748 * 2) Poison errors
749 *	a) Indicated by MCA_STATUS[43]: poison. Defined for all banks except legacy
750 *	   northbridge (bank 4).
751 *	b) Refers to poison consumption in the core. Does not include "no action",
752 *	   "action optional", or "deferred" error severities.
753 *	c) Will include a usable address so that immediate action can be taken.
754 * 3) Northbridge DRAM ECC errors
755 *	a) Reported in legacy bank 4 with extended error code (XEC) 8.
756 *	b) MCA_STATUS[43] is *not* defined as poison in legacy bank 4. Therefore,
757 *	   this bit should not be checked.
758 *
759 * NOTE: SMCA UMC memory errors fall into case #1.
760 */
761bool amd_mce_usable_address(struct mce *m)
762{
763	/* Check special northbridge case 3) first. */
764	if (!mce_flags.smca) {
765		if (legacy_mce_is_memory_error(m))
766			return true;
767		else if (m->bank == 4)
768			return false;
769	}
770
771	/* Check poison bit for all other bank types. */
772	if (m->status & MCI_STATUS_POISON)
773		return true;
774
775	/* Assume address is not usable for all others. */
776	return false;
777}
778
779static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
780{
781	struct mce m;
782
783	mce_setup(&m);
784
785	m.status = status;
786	m.misc   = misc;
787	m.bank   = bank;
788	m.tsc	 = rdtsc();
789
790	if (m.status & MCI_STATUS_ADDRV) {
791		m.addr = addr;
792
793		smca_extract_err_addr(&m);
794	}
795
796	if (mce_flags.smca) {
797		rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
798
799		if (m.status & MCI_STATUS_SYNDV)
800			rdmsrl(MSR_AMD64_SMCA_MCx_SYND(bank), m.synd);
801	}
802
803	mce_log(&m);
804}
805
806DEFINE_IDTENTRY_SYSVEC(sysvec_deferred_error)
807{
808	trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
809	inc_irq_stat(irq_deferred_error_count);
810	deferred_error_int_vector();
811	trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
812	apic_eoi();
813}
814
815/*
816 * Returns true if the logged error is deferred. False, otherwise.
817 */
818static inline bool
819_log_error_bank(unsigned int bank, u32 msr_stat, u32 msr_addr, u64 misc)
820{
821	u64 status, addr = 0;
822
823	rdmsrl(msr_stat, status);
824	if (!(status & MCI_STATUS_VAL))
825		return false;
826
827	if (status & MCI_STATUS_ADDRV)
828		rdmsrl(msr_addr, addr);
829
830	__log_error(bank, status, addr, misc);
831
832	wrmsrl(msr_stat, 0);
833
834	return status & MCI_STATUS_DEFERRED;
835}
836
837static bool _log_error_deferred(unsigned int bank, u32 misc)
838{
839	if (!_log_error_bank(bank, mca_msr_reg(bank, MCA_STATUS),
840			     mca_msr_reg(bank, MCA_ADDR), misc))
841		return false;
842
843	/*
844	 * Non-SMCA systems don't have MCA_DESTAT/MCA_DEADDR registers.
845	 * Return true here to avoid accessing these registers.
846	 */
847	if (!mce_flags.smca)
848		return true;
849
850	/* Clear MCA_DESTAT if the deferred error was logged from MCA_STATUS. */
851	wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(bank), 0);
852	return true;
853}
854
855/*
856 * We have three scenarios for checking for Deferred errors:
857 *
858 * 1) Non-SMCA systems check MCA_STATUS and log error if found.
859 * 2) SMCA systems check MCA_STATUS. If error is found then log it and also
860 *    clear MCA_DESTAT.
861 * 3) SMCA systems check MCA_DESTAT, if error was not found in MCA_STATUS, and
862 *    log it.
863 */
864static void log_error_deferred(unsigned int bank)
865{
866	if (_log_error_deferred(bank, 0))
867		return;
868
869	/*
870	 * Only deferred errors are logged in MCA_DE{STAT,ADDR} so just check
871	 * for a valid error.
872	 */
873	_log_error_bank(bank, MSR_AMD64_SMCA_MCx_DESTAT(bank),
874			      MSR_AMD64_SMCA_MCx_DEADDR(bank), 0);
875}
876
877/* APIC interrupt handler for deferred errors */
878static void amd_deferred_error_interrupt(void)
879{
880	unsigned int bank;
881
882	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank)
883		log_error_deferred(bank);
884}
885
886static void log_error_thresholding(unsigned int bank, u64 misc)
887{
888	_log_error_deferred(bank, misc);
889}
890
891static void log_and_reset_block(struct threshold_block *block)
892{
893	struct thresh_restart tr;
894	u32 low = 0, high = 0;
895
896	if (!block)
897		return;
898
899	if (rdmsr_safe(block->address, &low, &high))
900		return;
901
902	if (!(high & MASK_OVERFLOW_HI))
903		return;
904
905	/* Log the MCE which caused the threshold event. */
906	log_error_thresholding(block->bank, ((u64)high << 32) | low);
907
908	/* Reset threshold block after logging error. */
909	memset(&tr, 0, sizeof(tr));
910	tr.b = block;
911	threshold_restart_bank(&tr);
912}
913
914/*
915 * Threshold interrupt handler will service THRESHOLD_APIC_VECTOR. The interrupt
916 * goes off when error_count reaches threshold_limit.
917 */
918static void amd_threshold_interrupt(void)
919{
920	struct threshold_block *first_block = NULL, *block = NULL, *tmp = NULL;
921	struct threshold_bank **bp = this_cpu_read(threshold_banks);
922	unsigned int bank, cpu = smp_processor_id();
923
924	/*
925	 * Validate that the threshold bank has been initialized already. The
926	 * handler is installed at boot time, but on a hotplug event the
927	 * interrupt might fire before the data has been initialized.
928	 */
929	if (!bp)
930		return;
931
932	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
933		if (!(per_cpu(bank_map, cpu) & BIT_ULL(bank)))
934			continue;
935
936		first_block = bp[bank]->blocks;
937		if (!first_block)
938			continue;
939
940		/*
941		 * The first block is also the head of the list. Check it first
942		 * before iterating over the rest.
943		 */
944		log_and_reset_block(first_block);
945		list_for_each_entry_safe(block, tmp, &first_block->miscj, miscj)
946			log_and_reset_block(block);
947	}
948}
949
950/*
951 * Sysfs Interface
952 */
953
954struct threshold_attr {
955	struct attribute attr;
956	ssize_t (*show) (struct threshold_block *, char *);
957	ssize_t (*store) (struct threshold_block *, const char *, size_t count);
958};
959
960#define SHOW_FIELDS(name)						\
961static ssize_t show_ ## name(struct threshold_block *b, char *buf)	\
962{									\
963	return sprintf(buf, "%lu\n", (unsigned long) b->name);		\
964}
965SHOW_FIELDS(interrupt_enable)
966SHOW_FIELDS(threshold_limit)
967
968static ssize_t
969store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
970{
971	struct thresh_restart tr;
972	unsigned long new;
973
974	if (!b->interrupt_capable)
975		return -EINVAL;
976
977	if (kstrtoul(buf, 0, &new) < 0)
978		return -EINVAL;
979
980	b->interrupt_enable = !!new;
981
982	memset(&tr, 0, sizeof(tr));
983	tr.b		= b;
984
985	if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
986		return -ENODEV;
987
988	return size;
989}
990
991static ssize_t
992store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
993{
994	struct thresh_restart tr;
995	unsigned long new;
996
997	if (kstrtoul(buf, 0, &new) < 0)
998		return -EINVAL;
999
1000	if (new > THRESHOLD_MAX)
1001		new = THRESHOLD_MAX;
1002	if (new < 1)
1003		new = 1;
1004
1005	memset(&tr, 0, sizeof(tr));
1006	tr.old_limit = b->threshold_limit;
1007	b->threshold_limit = new;
1008	tr.b = b;
1009
1010	if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
1011		return -ENODEV;
1012
1013	return size;
1014}
1015
1016static ssize_t show_error_count(struct threshold_block *b, char *buf)
1017{
1018	u32 lo, hi;
1019
1020	/* CPU might be offline by now */
1021	if (rdmsr_on_cpu(b->cpu, b->address, &lo, &hi))
1022		return -ENODEV;
1023
1024	return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
1025				     (THRESHOLD_MAX - b->threshold_limit)));
1026}
1027
1028static struct threshold_attr error_count = {
1029	.attr = {.name = __stringify(error_count), .mode = 0444 },
1030	.show = show_error_count,
1031};
1032
1033#define RW_ATTR(val)							\
1034static struct threshold_attr val = {					\
1035	.attr	= {.name = __stringify(val), .mode = 0644 },		\
1036	.show	= show_## val,						\
1037	.store	= store_## val,						\
1038};
1039
1040RW_ATTR(interrupt_enable);
1041RW_ATTR(threshold_limit);
1042
1043static struct attribute *default_attrs[] = {
1044	&threshold_limit.attr,
1045	&error_count.attr,
1046	NULL,	/* possibly interrupt_enable if supported, see below */
1047	NULL,
1048};
1049ATTRIBUTE_GROUPS(default);
1050
1051#define to_block(k)	container_of(k, struct threshold_block, kobj)
1052#define to_attr(a)	container_of(a, struct threshold_attr, attr)
1053
1054static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
1055{
1056	struct threshold_block *b = to_block(kobj);
1057	struct threshold_attr *a = to_attr(attr);
1058	ssize_t ret;
1059
1060	ret = a->show ? a->show(b, buf) : -EIO;
1061
1062	return ret;
1063}
1064
1065static ssize_t store(struct kobject *kobj, struct attribute *attr,
1066		     const char *buf, size_t count)
1067{
1068	struct threshold_block *b = to_block(kobj);
1069	struct threshold_attr *a = to_attr(attr);
1070	ssize_t ret;
1071
1072	ret = a->store ? a->store(b, buf, count) : -EIO;
1073
1074	return ret;
1075}
1076
1077static const struct sysfs_ops threshold_ops = {
1078	.show			= show,
1079	.store			= store,
1080};
1081
1082static void threshold_block_release(struct kobject *kobj);
1083
1084static const struct kobj_type threshold_ktype = {
1085	.sysfs_ops		= &threshold_ops,
1086	.default_groups		= default_groups,
1087	.release		= threshold_block_release,
1088};
1089
1090static const char *get_name(unsigned int cpu, unsigned int bank, struct threshold_block *b)
1091{
1092	enum smca_bank_types bank_type;
1093
1094	if (!mce_flags.smca) {
1095		if (b && bank == 4)
1096			return bank4_names(b);
1097
1098		return th_names[bank];
1099	}
1100
1101	bank_type = smca_get_bank_type(cpu, bank);
1102	if (bank_type >= N_SMCA_BANK_TYPES)
1103		return NULL;
1104
1105	if (b && (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2)) {
1106		if (b->block < ARRAY_SIZE(smca_umc_block_names))
1107			return smca_umc_block_names[b->block];
1108		return NULL;
1109	}
1110
1111	if (per_cpu(smca_bank_counts, cpu)[bank_type] == 1)
1112		return smca_get_name(bank_type);
1113
1114	snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
1115		 "%s_%u", smca_get_name(bank_type),
1116			  per_cpu(smca_banks, cpu)[bank].sysfs_id);
1117	return buf_mcatype;
1118}
1119
1120static int allocate_threshold_blocks(unsigned int cpu, struct threshold_bank *tb,
1121				     unsigned int bank, unsigned int block,
1122				     u32 address)
1123{
1124	struct threshold_block *b = NULL;
1125	u32 low, high;
1126	int err;
1127
1128	if ((bank >= this_cpu_read(mce_num_banks)) || (block >= NR_BLOCKS))
1129		return 0;
1130
1131	if (rdmsr_safe(address, &low, &high))
1132		return 0;
1133
1134	if (!(high & MASK_VALID_HI)) {
1135		if (block)
1136			goto recurse;
1137		else
1138			return 0;
1139	}
1140
1141	if (!(high & MASK_CNTP_HI)  ||
1142	     (high & MASK_LOCKED_HI))
1143		goto recurse;
1144
1145	b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
1146	if (!b)
1147		return -ENOMEM;
1148
1149	b->block		= block;
1150	b->bank			= bank;
1151	b->cpu			= cpu;
1152	b->address		= address;
1153	b->interrupt_enable	= 0;
1154	b->interrupt_capable	= lvt_interrupt_supported(bank, high);
1155	b->threshold_limit	= THRESHOLD_MAX;
1156
1157	if (b->interrupt_capable) {
1158		default_attrs[2] = &interrupt_enable.attr;
1159		b->interrupt_enable = 1;
1160	} else {
1161		default_attrs[2] = NULL;
1162	}
1163
1164	INIT_LIST_HEAD(&b->miscj);
1165
1166	/* This is safe as @tb is not visible yet */
1167	if (tb->blocks)
1168		list_add(&b->miscj, &tb->blocks->miscj);
1169	else
1170		tb->blocks = b;
1171
1172	err = kobject_init_and_add(&b->kobj, &threshold_ktype, tb->kobj, get_name(cpu, bank, b));
1173	if (err)
1174		goto out_free;
1175recurse:
1176	address = get_block_address(address, low, high, bank, ++block, cpu);
1177	if (!address)
1178		return 0;
1179
1180	err = allocate_threshold_blocks(cpu, tb, bank, block, address);
1181	if (err)
1182		goto out_free;
1183
1184	if (b)
1185		kobject_uevent(&b->kobj, KOBJ_ADD);
1186
1187	return 0;
1188
1189out_free:
1190	if (b) {
1191		list_del(&b->miscj);
1192		kobject_put(&b->kobj);
1193	}
1194	return err;
1195}
1196
1197static int __threshold_add_blocks(struct threshold_bank *b)
1198{
1199	struct list_head *head = &b->blocks->miscj;
1200	struct threshold_block *pos = NULL;
1201	struct threshold_block *tmp = NULL;
1202	int err = 0;
1203
1204	err = kobject_add(&b->blocks->kobj, b->kobj, b->blocks->kobj.name);
1205	if (err)
1206		return err;
1207
1208	list_for_each_entry_safe(pos, tmp, head, miscj) {
1209
1210		err = kobject_add(&pos->kobj, b->kobj, pos->kobj.name);
1211		if (err) {
1212			list_for_each_entry_safe_reverse(pos, tmp, head, miscj)
1213				kobject_del(&pos->kobj);
1214
1215			return err;
1216		}
1217	}
1218	return err;
1219}
1220
1221static int threshold_create_bank(struct threshold_bank **bp, unsigned int cpu,
1222				 unsigned int bank)
1223{
1224	struct device *dev = this_cpu_read(mce_device);
1225	struct amd_northbridge *nb = NULL;
1226	struct threshold_bank *b = NULL;
1227	const char *name = get_name(cpu, bank, NULL);
1228	int err = 0;
1229
1230	if (!dev)
1231		return -ENODEV;
1232
1233	if (is_shared_bank(bank)) {
1234		nb = node_to_amd_nb(topology_amd_node_id(cpu));
1235
1236		/* threshold descriptor already initialized on this node? */
1237		if (nb && nb->bank4) {
1238			/* yes, use it */
1239			b = nb->bank4;
1240			err = kobject_add(b->kobj, &dev->kobj, name);
1241			if (err)
1242				goto out;
1243
1244			bp[bank] = b;
1245			refcount_inc(&b->cpus);
1246
1247			err = __threshold_add_blocks(b);
1248
1249			goto out;
1250		}
1251	}
1252
1253	b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
1254	if (!b) {
1255		err = -ENOMEM;
1256		goto out;
1257	}
1258
1259	/* Associate the bank with the per-CPU MCE device */
1260	b->kobj = kobject_create_and_add(name, &dev->kobj);
1261	if (!b->kobj) {
1262		err = -EINVAL;
1263		goto out_free;
1264	}
1265
1266	if (is_shared_bank(bank)) {
1267		b->shared = 1;
1268		refcount_set(&b->cpus, 1);
1269
1270		/* nb is already initialized, see above */
1271		if (nb) {
1272			WARN_ON(nb->bank4);
1273			nb->bank4 = b;
1274		}
1275	}
1276
1277	err = allocate_threshold_blocks(cpu, b, bank, 0, mca_msr_reg(bank, MCA_MISC));
1278	if (err)
1279		goto out_kobj;
1280
1281	bp[bank] = b;
1282	return 0;
1283
1284out_kobj:
1285	kobject_put(b->kobj);
1286out_free:
1287	kfree(b);
1288out:
1289	return err;
1290}
1291
1292static void threshold_block_release(struct kobject *kobj)
1293{
1294	kfree(to_block(kobj));
1295}
1296
1297static void deallocate_threshold_blocks(struct threshold_bank *bank)
1298{
1299	struct threshold_block *pos, *tmp;
1300
1301	list_for_each_entry_safe(pos, tmp, &bank->blocks->miscj, miscj) {
1302		list_del(&pos->miscj);
1303		kobject_put(&pos->kobj);
1304	}
1305
1306	kobject_put(&bank->blocks->kobj);
1307}
1308
1309static void __threshold_remove_blocks(struct threshold_bank *b)
1310{
1311	struct threshold_block *pos = NULL;
1312	struct threshold_block *tmp = NULL;
1313
1314	kobject_put(b->kobj);
1315
1316	list_for_each_entry_safe(pos, tmp, &b->blocks->miscj, miscj)
1317		kobject_put(b->kobj);
1318}
1319
1320static void threshold_remove_bank(struct threshold_bank *bank)
1321{
1322	struct amd_northbridge *nb;
1323
1324	if (!bank->blocks)
1325		goto out_free;
1326
1327	if (!bank->shared)
1328		goto out_dealloc;
1329
1330	if (!refcount_dec_and_test(&bank->cpus)) {
1331		__threshold_remove_blocks(bank);
1332		return;
1333	} else {
1334		/*
1335		 * The last CPU on this node using the shared bank is going
1336		 * away, remove that bank now.
1337		 */
1338		nb = node_to_amd_nb(topology_amd_node_id(smp_processor_id()));
1339		nb->bank4 = NULL;
1340	}
1341
1342out_dealloc:
1343	deallocate_threshold_blocks(bank);
1344
1345out_free:
1346	kobject_put(bank->kobj);
1347	kfree(bank);
1348}
1349
1350static void __threshold_remove_device(struct threshold_bank **bp)
1351{
1352	unsigned int bank, numbanks = this_cpu_read(mce_num_banks);
1353
1354	for (bank = 0; bank < numbanks; bank++) {
1355		if (!bp[bank])
1356			continue;
1357
1358		threshold_remove_bank(bp[bank]);
1359		bp[bank] = NULL;
1360	}
1361	kfree(bp);
1362}
1363
1364int mce_threshold_remove_device(unsigned int cpu)
1365{
1366	struct threshold_bank **bp = this_cpu_read(threshold_banks);
1367
1368	if (!bp)
1369		return 0;
1370
1371	/*
1372	 * Clear the pointer before cleaning up, so that the interrupt won't
1373	 * touch anything of this.
1374	 */
1375	this_cpu_write(threshold_banks, NULL);
1376
1377	__threshold_remove_device(bp);
1378	return 0;
1379}
1380
1381/**
1382 * mce_threshold_create_device - Create the per-CPU MCE threshold device
1383 * @cpu:	The plugged in CPU
1384 *
1385 * Create directories and files for all valid threshold banks.
1386 *
1387 * This is invoked from the CPU hotplug callback which was installed in
1388 * mcheck_init_device(). The invocation happens in context of the hotplug
1389 * thread running on @cpu.  The callback is invoked on all CPUs which are
1390 * online when the callback is installed or during a real hotplug event.
1391 */
1392int mce_threshold_create_device(unsigned int cpu)
1393{
1394	unsigned int numbanks, bank;
1395	struct threshold_bank **bp;
1396	int err;
1397
1398	if (!mce_flags.amd_threshold)
1399		return 0;
1400
1401	bp = this_cpu_read(threshold_banks);
1402	if (bp)
1403		return 0;
1404
1405	numbanks = this_cpu_read(mce_num_banks);
1406	bp = kcalloc(numbanks, sizeof(*bp), GFP_KERNEL);
1407	if (!bp)
1408		return -ENOMEM;
1409
1410	for (bank = 0; bank < numbanks; ++bank) {
1411		if (!(this_cpu_read(bank_map) & BIT_ULL(bank)))
1412			continue;
1413		err = threshold_create_bank(bp, cpu, bank);
1414		if (err) {
1415			__threshold_remove_device(bp);
1416			return err;
1417		}
1418	}
1419	this_cpu_write(threshold_banks, bp);
1420
1421	if (thresholding_irq_en)
1422		mce_threshold_vector = amd_threshold_interrupt;
1423	return 0;
1424}
1425