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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/apic.h>
27 #include <asm/mce.h>
28 #include <asm/msr.h>
29 #include <asm/trace/irq_vectors.h>
30
31 #define NR_BLOCKS 5
32 #define THRESHOLD_MAX 0xFFF
33 #define INT_TYPE_APIC 0x00020000
34 #define MASK_VALID_HI 0x80000000
35 #define MASK_CNTP_HI 0x40000000
36 #define MASK_LOCKED_HI 0x20000000
37 #define MASK_LVTOFF_HI 0x00F00000
38 #define MASK_COUNT_EN_HI 0x00080000
39 #define MASK_INT_TYPE_HI 0x00060000
40 #define MASK_OVERFLOW_HI 0x00010000
41 #define MASK_ERR_COUNT_HI 0x00000FFF
42 #define MASK_BLKPTR_LO 0xFF000000
43 #define MCG_XBLK_ADDR 0xC0000400
44
45 /* Deferred error settings */
46 #define MSR_CU_DEF_ERR 0xC0000410
47 #define MASK_DEF_LVTOFF 0x000000F0
48 #define MASK_DEF_INT_TYPE 0x00000006
49 #define DEF_LVT_OFF 0x2
50 #define DEF_INT_TYPE_APIC 0x2
51
52 /* Scalable MCA: */
53
54 /* Threshold LVT offset is at MSR0xC0000410[15:12] */
55 #define SMCA_THR_LVT_OFF 0xF000
56
57 static bool thresholding_en;
58
59 static const char * const th_names[] = {
60 "load_store",
61 "insn_fetch",
62 "combined_unit",
63 "",
64 "northbridge",
65 "execution_unit",
66 };
67
68 static const char * const smca_umc_block_names[] = {
69 "dram_ecc",
70 "misc_umc"
71 };
72
73 struct smca_bank_name {
74 const char *name; /* Short name for sysfs */
75 const char *long_name; /* Long name for pretty-printing */
76 };
77
78 static struct smca_bank_name smca_names[] = {
79 [SMCA_LS] = { "load_store", "Load Store Unit" },
80 [SMCA_IF] = { "insn_fetch", "Instruction Fetch Unit" },
81 [SMCA_L2_CACHE] = { "l2_cache", "L2 Cache" },
82 [SMCA_DE] = { "decode_unit", "Decode Unit" },
83 [SMCA_EX] = { "execution_unit", "Execution Unit" },
84 [SMCA_FP] = { "floating_point", "Floating Point Unit" },
85 [SMCA_L3_CACHE] = { "l3_cache", "L3 Cache" },
86 [SMCA_CS] = { "coherent_slave", "Coherent Slave" },
87 [SMCA_PIE] = { "pie", "Power, Interrupts, etc." },
88 [SMCA_UMC] = { "umc", "Unified Memory Controller" },
89 [SMCA_PB] = { "param_block", "Parameter Block" },
90 [SMCA_PSP] = { "psp", "Platform Security Processor" },
91 [SMCA_SMU] = { "smu", "System Management Unit" },
92 };
93
94 const char *smca_get_name(enum smca_bank_types t)
95 {
96 if (t >= N_SMCA_BANK_TYPES)
97 return NULL;
98
99 return smca_names[t].name;
100 }
101
102 const char *smca_get_long_name(enum smca_bank_types t)
103 {
104 if (t >= N_SMCA_BANK_TYPES)
105 return NULL;
106
107 return smca_names[t].long_name;
108 }
109 EXPORT_SYMBOL_GPL(smca_get_long_name);
110
111 static struct smca_hwid smca_hwid_mcatypes[] = {
112 /* { bank_type, hwid_mcatype, xec_bitmap } */
113
114 /* ZN Core (HWID=0xB0) MCA types */
115 { SMCA_LS, HWID_MCATYPE(0xB0, 0x0), 0x1FFFEF },
116 { SMCA_IF, HWID_MCATYPE(0xB0, 0x1), 0x3FFF },
117 { SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2), 0xF },
118 { SMCA_DE, HWID_MCATYPE(0xB0, 0x3), 0x1FF },
119 /* HWID 0xB0 MCATYPE 0x4 is Reserved */
120 { SMCA_EX, HWID_MCATYPE(0xB0, 0x5), 0x7FF },
121 { SMCA_FP, HWID_MCATYPE(0xB0, 0x6), 0x7F },
122 { SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7), 0xFF },
123
124 /* Data Fabric MCA types */
125 { SMCA_CS, HWID_MCATYPE(0x2E, 0x0), 0x1FF },
126 { SMCA_PIE, HWID_MCATYPE(0x2E, 0x1), 0xF },
127
128 /* Unified Memory Controller MCA type */
129 { SMCA_UMC, HWID_MCATYPE(0x96, 0x0), 0x3F },
130
131 /* Parameter Block MCA type */
132 { SMCA_PB, HWID_MCATYPE(0x05, 0x0), 0x1 },
133
134 /* Platform Security Processor MCA type */
135 { SMCA_PSP, HWID_MCATYPE(0xFF, 0x0), 0x1 },
136
137 /* System Management Unit MCA type */
138 { SMCA_SMU, HWID_MCATYPE(0x01, 0x0), 0x1 },
139 };
140
141 struct smca_bank smca_banks[MAX_NR_BANKS];
142 EXPORT_SYMBOL_GPL(smca_banks);
143
144 /*
145 * In SMCA enabled processors, we can have multiple banks for a given IP type.
146 * So to define a unique name for each bank, we use a temp c-string to append
147 * the MCA_IPID[InstanceId] to type's name in get_name().
148 *
149 * InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
150 * is greater than 8 plus 1 (for underscore) plus length of longest type name.
151 */
152 #define MAX_MCATYPE_NAME_LEN 30
153 static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
154
155 static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
156 static DEFINE_PER_CPU(unsigned int, bank_map); /* see which banks are on */
157
158 static void amd_threshold_interrupt(void);
159 static void amd_deferred_error_interrupt(void);
160
161 static void default_deferred_error_interrupt(void)
162 {
163 pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
164 }
165 void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
166
167 static void get_smca_bank_info(unsigned int bank)
168 {
169 unsigned int i, hwid_mcatype, cpu = smp_processor_id();
170 struct smca_hwid *s_hwid;
171 u32 high, instance_id;
172
173 /* Collect bank_info using CPU 0 for now. */
174 if (cpu)
175 return;
176
177 if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_IPID(bank), &instance_id, &high)) {
178 pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
179 return;
180 }
181
182 hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
183 (high & MCI_IPID_MCATYPE) >> 16);
184
185 for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
186 s_hwid = &smca_hwid_mcatypes[i];
187 if (hwid_mcatype == s_hwid->hwid_mcatype) {
188
189 WARN(smca_banks[bank].hwid,
190 "Bank %s already initialized!\n",
191 smca_get_name(s_hwid->bank_type));
192
193 smca_banks[bank].hwid = s_hwid;
194 smca_banks[bank].id = instance_id;
195 smca_banks[bank].sysfs_id = s_hwid->count++;
196 break;
197 }
198 }
199 }
200
201 struct thresh_restart {
202 struct threshold_block *b;
203 int reset;
204 int set_lvt_off;
205 int lvt_off;
206 u16 old_limit;
207 };
208
209 static inline bool is_shared_bank(int bank)
210 {
211 /*
212 * Scalable MCA provides for only one core to have access to the MSRs of
213 * a shared bank.
214 */
215 if (mce_flags.smca)
216 return false;
217
218 /* Bank 4 is for northbridge reporting and is thus shared */
219 return (bank == 4);
220 }
221
222 static const char *bank4_names(const struct threshold_block *b)
223 {
224 switch (b->address) {
225 /* MSR4_MISC0 */
226 case 0x00000413:
227 return "dram";
228
229 case 0xc0000408:
230 return "ht_links";
231
232 case 0xc0000409:
233 return "l3_cache";
234
235 default:
236 WARN(1, "Funny MSR: 0x%08x\n", b->address);
237 return "";
238 }
239 };
240
241
242 static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
243 {
244 /*
245 * bank 4 supports APIC LVT interrupts implicitly since forever.
246 */
247 if (bank == 4)
248 return true;
249
250 /*
251 * IntP: interrupt present; if this bit is set, the thresholding
252 * bank can generate APIC LVT interrupts
253 */
254 return msr_high_bits & BIT(28);
255 }
256
257 static int lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
258 {
259 int msr = (hi & MASK_LVTOFF_HI) >> 20;
260
261 if (apic < 0) {
262 pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
263 "for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
264 b->bank, b->block, b->address, hi, lo);
265 return 0;
266 }
267
268 if (apic != msr) {
269 /*
270 * On SMCA CPUs, LVT offset is programmed at a different MSR, and
271 * the BIOS provides the value. The original field where LVT offset
272 * was set is reserved. Return early here:
273 */
274 if (mce_flags.smca)
275 return 0;
276
277 pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
278 "for bank %d, block %d (MSR%08X=0x%x%08x)\n",
279 b->cpu, apic, b->bank, b->block, b->address, hi, lo);
280 return 0;
281 }
282
283 return 1;
284 };
285
286 /* Reprogram MCx_MISC MSR behind this threshold bank. */
287 static void threshold_restart_bank(void *_tr)
288 {
289 struct thresh_restart *tr = _tr;
290 u32 hi, lo;
291
292 rdmsr(tr->b->address, lo, hi);
293
294 if (tr->b->threshold_limit < (hi & THRESHOLD_MAX))
295 tr->reset = 1; /* limit cannot be lower than err count */
296
297 if (tr->reset) { /* reset err count and overflow bit */
298 hi =
299 (hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
300 (THRESHOLD_MAX - tr->b->threshold_limit);
301 } else if (tr->old_limit) { /* change limit w/o reset */
302 int new_count = (hi & THRESHOLD_MAX) +
303 (tr->old_limit - tr->b->threshold_limit);
304
305 hi = (hi & ~MASK_ERR_COUNT_HI) |
306 (new_count & THRESHOLD_MAX);
307 }
308
309 /* clear IntType */
310 hi &= ~MASK_INT_TYPE_HI;
311
312 if (!tr->b->interrupt_capable)
313 goto done;
314
315 if (tr->set_lvt_off) {
316 if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
317 /* set new lvt offset */
318 hi &= ~MASK_LVTOFF_HI;
319 hi |= tr->lvt_off << 20;
320 }
321 }
322
323 if (tr->b->interrupt_enable)
324 hi |= INT_TYPE_APIC;
325
326 done:
327
328 hi |= MASK_COUNT_EN_HI;
329 wrmsr(tr->b->address, lo, hi);
330 }
331
332 static void mce_threshold_block_init(struct threshold_block *b, int offset)
333 {
334 struct thresh_restart tr = {
335 .b = b,
336 .set_lvt_off = 1,
337 .lvt_off = offset,
338 };
339
340 b->threshold_limit = THRESHOLD_MAX;
341 threshold_restart_bank(&tr);
342 };
343
344 static int setup_APIC_mce_threshold(int reserved, int new)
345 {
346 if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
347 APIC_EILVT_MSG_FIX, 0))
348 return new;
349
350 return reserved;
351 }
352
353 static int setup_APIC_deferred_error(int reserved, int new)
354 {
355 if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
356 APIC_EILVT_MSG_FIX, 0))
357 return new;
358
359 return reserved;
360 }
361
362 static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
363 {
364 u32 low = 0, high = 0;
365 int def_offset = -1, def_new;
366
367 if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
368 return;
369
370 def_new = (low & MASK_DEF_LVTOFF) >> 4;
371 if (!(low & MASK_DEF_LVTOFF)) {
372 pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
373 def_new = DEF_LVT_OFF;
374 low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
375 }
376
377 def_offset = setup_APIC_deferred_error(def_offset, def_new);
378 if ((def_offset == def_new) &&
379 (deferred_error_int_vector != amd_deferred_error_interrupt))
380 deferred_error_int_vector = amd_deferred_error_interrupt;
381
382 low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
383 wrmsr(MSR_CU_DEF_ERR, low, high);
384 }
385
386 static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 high,
387 unsigned int bank, unsigned int block)
388 {
389 u32 addr = 0, offset = 0;
390
391 if (mce_flags.smca) {
392 if (!block) {
393 addr = MSR_AMD64_SMCA_MCx_MISC(bank);
394 } else {
395 /*
396 * For SMCA enabled processors, BLKPTR field of the
397 * first MISC register (MCx_MISC0) indicates presence of
398 * additional MISC register set (MISC1-4).
399 */
400 u32 low, high;
401
402 if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
403 return addr;
404
405 if (!(low & MCI_CONFIG_MCAX))
406 return addr;
407
408 if (!rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high) &&
409 (low & MASK_BLKPTR_LO))
410 addr = MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
411 }
412 return addr;
413 }
414
415 /* Fall back to method we used for older processors: */
416 switch (block) {
417 case 0:
418 addr = msr_ops.misc(bank);
419 break;
420 case 1:
421 offset = ((low & MASK_BLKPTR_LO) >> 21);
422 if (offset)
423 addr = MCG_XBLK_ADDR + offset;
424 break;
425 default:
426 addr = ++current_addr;
427 }
428 return addr;
429 }
430
431 static int
432 prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
433 int offset, u32 misc_high)
434 {
435 unsigned int cpu = smp_processor_id();
436 u32 smca_low, smca_high, smca_addr;
437 struct threshold_block b;
438 int new;
439
440 if (!block)
441 per_cpu(bank_map, cpu) |= (1 << bank);
442
443 memset(&b, 0, sizeof(b));
444 b.cpu = cpu;
445 b.bank = bank;
446 b.block = block;
447 b.address = addr;
448 b.interrupt_capable = lvt_interrupt_supported(bank, misc_high);
449
450 if (!b.interrupt_capable)
451 goto done;
452
453 b.interrupt_enable = 1;
454
455 if (!mce_flags.smca) {
456 new = (misc_high & MASK_LVTOFF_HI) >> 20;
457 goto set_offset;
458 }
459
460 smca_addr = MSR_AMD64_SMCA_MCx_CONFIG(bank);
461
462 if (!rdmsr_safe(smca_addr, &smca_low, &smca_high)) {
463 /*
464 * OS is required to set the MCAX bit to acknowledge that it is
465 * now using the new MSR ranges and new registers under each
466 * bank. It also means that the OS will configure deferred
467 * errors in the new MCx_CONFIG register. If the bit is not set,
468 * uncorrectable errors will cause a system panic.
469 *
470 * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
471 */
472 smca_high |= BIT(0);
473
474 /*
475 * SMCA logs Deferred Error information in MCA_DE{STAT,ADDR}
476 * registers with the option of additionally logging to
477 * MCA_{STATUS,ADDR} if MCA_CONFIG[LogDeferredInMcaStat] is set.
478 *
479 * This bit is usually set by BIOS to retain the old behavior
480 * for OSes that don't use the new registers. Linux supports the
481 * new registers so let's disable that additional logging here.
482 *
483 * MCA_CONFIG[LogDeferredInMcaStat] is bit 34 (bit 2 in the high
484 * portion of the MSR).
485 */
486 smca_high &= ~BIT(2);
487
488 /*
489 * SMCA sets the Deferred Error Interrupt type per bank.
490 *
491 * MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
492 * if the DeferredIntType bit field is available.
493 *
494 * MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
495 * high portion of the MSR). OS should set this to 0x1 to enable
496 * APIC based interrupt. First, check that no interrupt has been
497 * set.
498 */
499 if ((smca_low & BIT(5)) && !((smca_high >> 5) & 0x3))
500 smca_high |= BIT(5);
501
502 wrmsr(smca_addr, smca_low, smca_high);
503 }
504
505 /* Gather LVT offset for thresholding: */
506 if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
507 goto out;
508
509 new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
510
511 set_offset:
512 offset = setup_APIC_mce_threshold(offset, new);
513
514 if ((offset == new) && (mce_threshold_vector != amd_threshold_interrupt))
515 mce_threshold_vector = amd_threshold_interrupt;
516
517 done:
518 mce_threshold_block_init(&b, offset);
519
520 out:
521 return offset;
522 }
523
524 /* cpu init entry point, called from mce.c with preempt off */
525 void mce_amd_feature_init(struct cpuinfo_x86 *c)
526 {
527 u32 low = 0, high = 0, address = 0;
528 unsigned int bank, block, cpu = smp_processor_id();
529 int offset = -1;
530
531 for (bank = 0; bank < mca_cfg.banks; ++bank) {
532 if (mce_flags.smca)
533 get_smca_bank_info(bank);
534
535 for (block = 0; block < NR_BLOCKS; ++block) {
536 address = get_block_address(cpu, address, low, high, bank, block);
537 if (!address)
538 break;
539
540 if (rdmsr_safe(address, &low, &high))
541 break;
542
543 if (!(high & MASK_VALID_HI))
544 continue;
545
546 if (!(high & MASK_CNTP_HI) ||
547 (high & MASK_LOCKED_HI))
548 continue;
549
550 offset = prepare_threshold_block(bank, block, address, offset, high);
551 }
552 }
553
554 if (mce_flags.succor)
555 deferred_error_interrupt_enable(c);
556 }
557
558 int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
559 {
560 u64 dram_base_addr, dram_limit_addr, dram_hole_base;
561 /* We start from the normalized address */
562 u64 ret_addr = norm_addr;
563
564 u32 tmp;
565
566 u8 die_id_shift, die_id_mask, socket_id_shift, socket_id_mask;
567 u8 intlv_num_dies, intlv_num_chan, intlv_num_sockets;
568 u8 intlv_addr_sel, intlv_addr_bit;
569 u8 num_intlv_bits, hashed_bit;
570 u8 lgcy_mmio_hole_en, base = 0;
571 u8 cs_mask, cs_id = 0;
572 bool hash_enabled = false;
573
574 /* Read D18F0x1B4 (DramOffset), check if base 1 is used. */
575 if (amd_df_indirect_read(nid, 0, 0x1B4, umc, &tmp))
576 goto out_err;
577
578 /* Remove HiAddrOffset from normalized address, if enabled: */
579 if (tmp & BIT(0)) {
580 u64 hi_addr_offset = (tmp & GENMASK_ULL(31, 20)) << 8;
581
582 if (norm_addr >= hi_addr_offset) {
583 ret_addr -= hi_addr_offset;
584 base = 1;
585 }
586 }
587
588 /* Read D18F0x110 (DramBaseAddress). */
589 if (amd_df_indirect_read(nid, 0, 0x110 + (8 * base), umc, &tmp))
590 goto out_err;
591
592 /* Check if address range is valid. */
593 if (!(tmp & BIT(0))) {
594 pr_err("%s: Invalid DramBaseAddress range: 0x%x.\n",
595 __func__, tmp);
596 goto out_err;
597 }
598
599 lgcy_mmio_hole_en = tmp & BIT(1);
600 intlv_num_chan = (tmp >> 4) & 0xF;
601 intlv_addr_sel = (tmp >> 8) & 0x7;
602 dram_base_addr = (tmp & GENMASK_ULL(31, 12)) << 16;
603
604 /* {0, 1, 2, 3} map to address bits {8, 9, 10, 11} respectively */
605 if (intlv_addr_sel > 3) {
606 pr_err("%s: Invalid interleave address select %d.\n",
607 __func__, intlv_addr_sel);
608 goto out_err;
609 }
610
611 /* Read D18F0x114 (DramLimitAddress). */
612 if (amd_df_indirect_read(nid, 0, 0x114 + (8 * base), umc, &tmp))
613 goto out_err;
614
615 intlv_num_sockets = (tmp >> 8) & 0x1;
616 intlv_num_dies = (tmp >> 10) & 0x3;
617 dram_limit_addr = ((tmp & GENMASK_ULL(31, 12)) << 16) | GENMASK_ULL(27, 0);
618
619 intlv_addr_bit = intlv_addr_sel + 8;
620
621 /* Re-use intlv_num_chan by setting it equal to log2(#channels) */
622 switch (intlv_num_chan) {
623 case 0: intlv_num_chan = 0; break;
624 case 1: intlv_num_chan = 1; break;
625 case 3: intlv_num_chan = 2; break;
626 case 5: intlv_num_chan = 3; break;
627 case 7: intlv_num_chan = 4; break;
628
629 case 8: intlv_num_chan = 1;
630 hash_enabled = true;
631 break;
632 default:
633 pr_err("%s: Invalid number of interleaved channels %d.\n",
634 __func__, intlv_num_chan);
635 goto out_err;
636 }
637
638 num_intlv_bits = intlv_num_chan;
639
640 if (intlv_num_dies > 2) {
641 pr_err("%s: Invalid number of interleaved nodes/dies %d.\n",
642 __func__, intlv_num_dies);
643 goto out_err;
644 }
645
646 num_intlv_bits += intlv_num_dies;
647
648 /* Add a bit if sockets are interleaved. */
649 num_intlv_bits += intlv_num_sockets;
650
651 /* Assert num_intlv_bits <= 4 */
652 if (num_intlv_bits > 4) {
653 pr_err("%s: Invalid interleave bits %d.\n",
654 __func__, num_intlv_bits);
655 goto out_err;
656 }
657
658 if (num_intlv_bits > 0) {
659 u64 temp_addr_x, temp_addr_i, temp_addr_y;
660 u8 die_id_bit, sock_id_bit, cs_fabric_id;
661
662 /*
663 * Read FabricBlockInstanceInformation3_CS[BlockFabricID].
664 * This is the fabric id for this coherent slave. Use
665 * umc/channel# as instance id of the coherent slave
666 * for FICAA.
667 */
668 if (amd_df_indirect_read(nid, 0, 0x50, umc, &tmp))
669 goto out_err;
670
671 cs_fabric_id = (tmp >> 8) & 0xFF;
672 die_id_bit = 0;
673
674 /* If interleaved over more than 1 channel: */
675 if (intlv_num_chan) {
676 die_id_bit = intlv_num_chan;
677 cs_mask = (1 << die_id_bit) - 1;
678 cs_id = cs_fabric_id & cs_mask;
679 }
680
681 sock_id_bit = die_id_bit;
682
683 /* Read D18F1x208 (SystemFabricIdMask). */
684 if (intlv_num_dies || intlv_num_sockets)
685 if (amd_df_indirect_read(nid, 1, 0x208, umc, &tmp))
686 goto out_err;
687
688 /* If interleaved over more than 1 die. */
689 if (intlv_num_dies) {
690 sock_id_bit = die_id_bit + intlv_num_dies;
691 die_id_shift = (tmp >> 24) & 0xF;
692 die_id_mask = (tmp >> 8) & 0xFF;
693
694 cs_id |= ((cs_fabric_id & die_id_mask) >> die_id_shift) << die_id_bit;
695 }
696
697 /* If interleaved over more than 1 socket. */
698 if (intlv_num_sockets) {
699 socket_id_shift = (tmp >> 28) & 0xF;
700 socket_id_mask = (tmp >> 16) & 0xFF;
701
702 cs_id |= ((cs_fabric_id & socket_id_mask) >> socket_id_shift) << sock_id_bit;
703 }
704
705 /*
706 * The pre-interleaved address consists of XXXXXXIIIYYYYY
707 * where III is the ID for this CS, and XXXXXXYYYYY are the
708 * address bits from the post-interleaved address.
709 * "num_intlv_bits" has been calculated to tell us how many "I"
710 * bits there are. "intlv_addr_bit" tells us how many "Y" bits
711 * there are (where "I" starts).
712 */
713 temp_addr_y = ret_addr & GENMASK_ULL(intlv_addr_bit-1, 0);
714 temp_addr_i = (cs_id << intlv_addr_bit);
715 temp_addr_x = (ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits;
716 ret_addr = temp_addr_x | temp_addr_i | temp_addr_y;
717 }
718
719 /* Add dram base address */
720 ret_addr += dram_base_addr;
721
722 /* If legacy MMIO hole enabled */
723 if (lgcy_mmio_hole_en) {
724 if (amd_df_indirect_read(nid, 0, 0x104, umc, &tmp))
725 goto out_err;
726
727 dram_hole_base = tmp & GENMASK(31, 24);
728 if (ret_addr >= dram_hole_base)
729 ret_addr += (BIT_ULL(32) - dram_hole_base);
730 }
731
732 if (hash_enabled) {
733 /* Save some parentheses and grab ls-bit at the end. */
734 hashed_bit = (ret_addr >> 12) ^
735 (ret_addr >> 18) ^
736 (ret_addr >> 21) ^
737 (ret_addr >> 30) ^
738 cs_id;
739
740 hashed_bit &= BIT(0);
741
742 if (hashed_bit != ((ret_addr >> intlv_addr_bit) & BIT(0)))
743 ret_addr ^= BIT(intlv_addr_bit);
744 }
745
746 /* Is calculated system address is above DRAM limit address? */
747 if (ret_addr > dram_limit_addr)
748 goto out_err;
749
750 *sys_addr = ret_addr;
751 return 0;
752
753 out_err:
754 return -EINVAL;
755 }
756 EXPORT_SYMBOL_GPL(umc_normaddr_to_sysaddr);
757
758 static void
759 __log_error(unsigned int bank, bool deferred_err, bool threshold_err, u64 misc)
760 {
761 u32 msr_status = msr_ops.status(bank);
762 u32 msr_addr = msr_ops.addr(bank);
763 struct mce m;
764 u64 status;
765
766 WARN_ON_ONCE(deferred_err && threshold_err);
767
768 if (deferred_err && mce_flags.smca) {
769 msr_status = MSR_AMD64_SMCA_MCx_DESTAT(bank);
770 msr_addr = MSR_AMD64_SMCA_MCx_DEADDR(bank);
771 }
772
773 rdmsrl(msr_status, status);
774
775 if (!(status & MCI_STATUS_VAL))
776 return;
777
778 mce_setup(&m);
779
780 m.status = status;
781 m.bank = bank;
782 m.tsc = rdtsc();
783
784 if (threshold_err)
785 m.misc = misc;
786
787 if (m.status & MCI_STATUS_ADDRV) {
788 rdmsrl(msr_addr, m.addr);
789
790 /*
791 * Extract [55:<lsb>] where lsb is the least significant
792 * *valid* bit of the address bits.
793 */
794 if (mce_flags.smca) {
795 u8 lsb = (m.addr >> 56) & 0x3f;
796
797 m.addr &= GENMASK_ULL(55, lsb);
798 }
799 }
800
801 if (mce_flags.smca) {
802 rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
803
804 if (m.status & MCI_STATUS_SYNDV)
805 rdmsrl(MSR_AMD64_SMCA_MCx_SYND(bank), m.synd);
806 }
807
808 mce_log(&m);
809
810 wrmsrl(msr_status, 0);
811 }
812
813 static inline void __smp_deferred_error_interrupt(void)
814 {
815 inc_irq_stat(irq_deferred_error_count);
816 deferred_error_int_vector();
817 }
818
819 asmlinkage __visible void __irq_entry smp_deferred_error_interrupt(void)
820 {
821 entering_irq();
822 __smp_deferred_error_interrupt();
823 exiting_ack_irq();
824 }
825
826 asmlinkage __visible void __irq_entry smp_trace_deferred_error_interrupt(void)
827 {
828 entering_irq();
829 trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
830 __smp_deferred_error_interrupt();
831 trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
832 exiting_ack_irq();
833 }
834
835 /* APIC interrupt handler for deferred errors */
836 static void amd_deferred_error_interrupt(void)
837 {
838 unsigned int bank;
839 u32 msr_status;
840 u64 status;
841
842 for (bank = 0; bank < mca_cfg.banks; ++bank) {
843 msr_status = (mce_flags.smca) ? MSR_AMD64_SMCA_MCx_DESTAT(bank)
844 : msr_ops.status(bank);
845
846 rdmsrl(msr_status, status);
847
848 if (!(status & MCI_STATUS_VAL) ||
849 !(status & MCI_STATUS_DEFERRED))
850 continue;
851
852 __log_error(bank, true, false, 0);
853 break;
854 }
855 }
856
857 /*
858 * APIC Interrupt Handler
859 */
860
861 /*
862 * threshold interrupt handler will service THRESHOLD_APIC_VECTOR.
863 * the interrupt goes off when error_count reaches threshold_limit.
864 * the handler will simply log mcelog w/ software defined bank number.
865 */
866
867 static void amd_threshold_interrupt(void)
868 {
869 u32 low = 0, high = 0, address = 0;
870 unsigned int bank, block, cpu = smp_processor_id();
871 struct thresh_restart tr;
872
873 /* assume first bank caused it */
874 for (bank = 0; bank < mca_cfg.banks; ++bank) {
875 if (!(per_cpu(bank_map, cpu) & (1 << bank)))
876 continue;
877 for (block = 0; block < NR_BLOCKS; ++block) {
878 address = get_block_address(cpu, address, low, high, bank, block);
879 if (!address)
880 break;
881
882 if (rdmsr_safe(address, &low, &high))
883 break;
884
885 if (!(high & MASK_VALID_HI)) {
886 if (block)
887 continue;
888 else
889 break;
890 }
891
892 if (!(high & MASK_CNTP_HI) ||
893 (high & MASK_LOCKED_HI))
894 continue;
895
896 /*
897 * Log the machine check that caused the threshold
898 * event.
899 */
900 if (high & MASK_OVERFLOW_HI)
901 goto log;
902 }
903 }
904 return;
905
906 log:
907 __log_error(bank, false, true, ((u64)high << 32) | low);
908
909 /* Reset threshold block after logging error. */
910 memset(&tr, 0, sizeof(tr));
911 tr.b = &per_cpu(threshold_banks, cpu)[bank]->blocks[block];
912 threshold_restart_bank(&tr);
913 }
914
915 /*
916 * Sysfs Interface
917 */
918
919 struct threshold_attr {
920 struct attribute attr;
921 ssize_t (*show) (struct threshold_block *, char *);
922 ssize_t (*store) (struct threshold_block *, const char *, size_t count);
923 };
924
925 #define SHOW_FIELDS(name) \
926 static ssize_t show_ ## name(struct threshold_block *b, char *buf) \
927 { \
928 return sprintf(buf, "%lu\n", (unsigned long) b->name); \
929 }
930 SHOW_FIELDS(interrupt_enable)
931 SHOW_FIELDS(threshold_limit)
932
933 static ssize_t
934 store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
935 {
936 struct thresh_restart tr;
937 unsigned long new;
938
939 if (!b->interrupt_capable)
940 return -EINVAL;
941
942 if (kstrtoul(buf, 0, &new) < 0)
943 return -EINVAL;
944
945 b->interrupt_enable = !!new;
946
947 memset(&tr, 0, sizeof(tr));
948 tr.b = b;
949
950 smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
951
952 return size;
953 }
954
955 static ssize_t
956 store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
957 {
958 struct thresh_restart tr;
959 unsigned long new;
960
961 if (kstrtoul(buf, 0, &new) < 0)
962 return -EINVAL;
963
964 if (new > THRESHOLD_MAX)
965 new = THRESHOLD_MAX;
966 if (new < 1)
967 new = 1;
968
969 memset(&tr, 0, sizeof(tr));
970 tr.old_limit = b->threshold_limit;
971 b->threshold_limit = new;
972 tr.b = b;
973
974 smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
975
976 return size;
977 }
978
979 static ssize_t show_error_count(struct threshold_block *b, char *buf)
980 {
981 u32 lo, hi;
982
983 rdmsr_on_cpu(b->cpu, b->address, &lo, &hi);
984
985 return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
986 (THRESHOLD_MAX - b->threshold_limit)));
987 }
988
989 static struct threshold_attr error_count = {
990 .attr = {.name = __stringify(error_count), .mode = 0444 },
991 .show = show_error_count,
992 };
993
994 #define RW_ATTR(val) \
995 static struct threshold_attr val = { \
996 .attr = {.name = __stringify(val), .mode = 0644 }, \
997 .show = show_## val, \
998 .store = store_## val, \
999 };
1000
1001 RW_ATTR(interrupt_enable);
1002 RW_ATTR(threshold_limit);
1003
1004 static struct attribute *default_attrs[] = {
1005 &threshold_limit.attr,
1006 &error_count.attr,
1007 NULL, /* possibly interrupt_enable if supported, see below */
1008 NULL,
1009 };
1010
1011 #define to_block(k) container_of(k, struct threshold_block, kobj)
1012 #define to_attr(a) container_of(a, struct threshold_attr, attr)
1013
1014 static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
1015 {
1016 struct threshold_block *b = to_block(kobj);
1017 struct threshold_attr *a = to_attr(attr);
1018 ssize_t ret;
1019
1020 ret = a->show ? a->show(b, buf) : -EIO;
1021
1022 return ret;
1023 }
1024
1025 static ssize_t store(struct kobject *kobj, struct attribute *attr,
1026 const char *buf, size_t count)
1027 {
1028 struct threshold_block *b = to_block(kobj);
1029 struct threshold_attr *a = to_attr(attr);
1030 ssize_t ret;
1031
1032 ret = a->store ? a->store(b, buf, count) : -EIO;
1033
1034 return ret;
1035 }
1036
1037 static const struct sysfs_ops threshold_ops = {
1038 .show = show,
1039 .store = store,
1040 };
1041
1042 static struct kobj_type threshold_ktype = {
1043 .sysfs_ops = &threshold_ops,
1044 .default_attrs = default_attrs,
1045 };
1046
1047 static const char *get_name(unsigned int bank, struct threshold_block *b)
1048 {
1049 unsigned int bank_type;
1050
1051 if (!mce_flags.smca) {
1052 if (b && bank == 4)
1053 return bank4_names(b);
1054
1055 return th_names[bank];
1056 }
1057
1058 if (!smca_banks[bank].hwid)
1059 return NULL;
1060
1061 bank_type = smca_banks[bank].hwid->bank_type;
1062
1063 if (b && bank_type == SMCA_UMC) {
1064 if (b->block < ARRAY_SIZE(smca_umc_block_names))
1065 return smca_umc_block_names[b->block];
1066 return NULL;
1067 }
1068
1069 if (smca_banks[bank].hwid->count == 1)
1070 return smca_get_name(bank_type);
1071
1072 snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
1073 "%s_%x", smca_get_name(bank_type),
1074 smca_banks[bank].sysfs_id);
1075 return buf_mcatype;
1076 }
1077
1078 static int allocate_threshold_blocks(unsigned int cpu, unsigned int bank,
1079 unsigned int block, u32 address)
1080 {
1081 struct threshold_block *b = NULL;
1082 u32 low, high;
1083 int err;
1084
1085 if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
1086 return 0;
1087
1088 if (rdmsr_safe_on_cpu(cpu, address, &low, &high))
1089 return 0;
1090
1091 if (!(high & MASK_VALID_HI)) {
1092 if (block)
1093 goto recurse;
1094 else
1095 return 0;
1096 }
1097
1098 if (!(high & MASK_CNTP_HI) ||
1099 (high & MASK_LOCKED_HI))
1100 goto recurse;
1101
1102 b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
1103 if (!b)
1104 return -ENOMEM;
1105
1106 b->block = block;
1107 b->bank = bank;
1108 b->cpu = cpu;
1109 b->address = address;
1110 b->interrupt_enable = 0;
1111 b->interrupt_capable = lvt_interrupt_supported(bank, high);
1112 b->threshold_limit = THRESHOLD_MAX;
1113
1114 if (b->interrupt_capable) {
1115 threshold_ktype.default_attrs[2] = &interrupt_enable.attr;
1116 b->interrupt_enable = 1;
1117 } else {
1118 threshold_ktype.default_attrs[2] = NULL;
1119 }
1120
1121 INIT_LIST_HEAD(&b->miscj);
1122
1123 if (per_cpu(threshold_banks, cpu)[bank]->blocks) {
1124 list_add(&b->miscj,
1125 &per_cpu(threshold_banks, cpu)[bank]->blocks->miscj);
1126 } else {
1127 per_cpu(threshold_banks, cpu)[bank]->blocks = b;
1128 }
1129
1130 err = kobject_init_and_add(&b->kobj, &threshold_ktype,
1131 per_cpu(threshold_banks, cpu)[bank]->kobj,
1132 get_name(bank, b));
1133 if (err)
1134 goto out_free;
1135 recurse:
1136 address = get_block_address(cpu, address, low, high, bank, ++block);
1137 if (!address)
1138 return 0;
1139
1140 err = allocate_threshold_blocks(cpu, bank, block, address);
1141 if (err)
1142 goto out_free;
1143
1144 if (b)
1145 kobject_uevent(&b->kobj, KOBJ_ADD);
1146
1147 return err;
1148
1149 out_free:
1150 if (b) {
1151 kobject_put(&b->kobj);
1152 list_del(&b->miscj);
1153 kfree(b);
1154 }
1155 return err;
1156 }
1157
1158 static int __threshold_add_blocks(struct threshold_bank *b)
1159 {
1160 struct list_head *head = &b->blocks->miscj;
1161 struct threshold_block *pos = NULL;
1162 struct threshold_block *tmp = NULL;
1163 int err = 0;
1164
1165 err = kobject_add(&b->blocks->kobj, b->kobj, b->blocks->kobj.name);
1166 if (err)
1167 return err;
1168
1169 list_for_each_entry_safe(pos, tmp, head, miscj) {
1170
1171 err = kobject_add(&pos->kobj, b->kobj, pos->kobj.name);
1172 if (err) {
1173 list_for_each_entry_safe_reverse(pos, tmp, head, miscj)
1174 kobject_del(&pos->kobj);
1175
1176 return err;
1177 }
1178 }
1179 return err;
1180 }
1181
1182 static int threshold_create_bank(unsigned int cpu, unsigned int bank)
1183 {
1184 struct device *dev = per_cpu(mce_device, cpu);
1185 struct amd_northbridge *nb = NULL;
1186 struct threshold_bank *b = NULL;
1187 const char *name = get_name(bank, NULL);
1188 int err = 0;
1189
1190 if (!dev)
1191 return -ENODEV;
1192
1193 if (is_shared_bank(bank)) {
1194 nb = node_to_amd_nb(amd_get_nb_id(cpu));
1195
1196 /* threshold descriptor already initialized on this node? */
1197 if (nb && nb->bank4) {
1198 /* yes, use it */
1199 b = nb->bank4;
1200 err = kobject_add(b->kobj, &dev->kobj, name);
1201 if (err)
1202 goto out;
1203
1204 per_cpu(threshold_banks, cpu)[bank] = b;
1205 atomic_inc(&b->cpus);
1206
1207 err = __threshold_add_blocks(b);
1208
1209 goto out;
1210 }
1211 }
1212
1213 b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
1214 if (!b) {
1215 err = -ENOMEM;
1216 goto out;
1217 }
1218
1219 b->kobj = kobject_create_and_add(name, &dev->kobj);
1220 if (!b->kobj) {
1221 err = -EINVAL;
1222 goto out_free;
1223 }
1224
1225 per_cpu(threshold_banks, cpu)[bank] = b;
1226
1227 if (is_shared_bank(bank)) {
1228 atomic_set(&b->cpus, 1);
1229
1230 /* nb is already initialized, see above */
1231 if (nb) {
1232 WARN_ON(nb->bank4);
1233 nb->bank4 = b;
1234 }
1235 }
1236
1237 err = allocate_threshold_blocks(cpu, bank, 0, msr_ops.misc(bank));
1238 if (!err)
1239 goto out;
1240
1241 out_free:
1242 kfree(b);
1243
1244 out:
1245 return err;
1246 }
1247
1248 static void deallocate_threshold_block(unsigned int cpu,
1249 unsigned int bank)
1250 {
1251 struct threshold_block *pos = NULL;
1252 struct threshold_block *tmp = NULL;
1253 struct threshold_bank *head = per_cpu(threshold_banks, cpu)[bank];
1254
1255 if (!head)
1256 return;
1257
1258 list_for_each_entry_safe(pos, tmp, &head->blocks->miscj, miscj) {
1259 kobject_put(&pos->kobj);
1260 list_del(&pos->miscj);
1261 kfree(pos);
1262 }
1263
1264 kfree(per_cpu(threshold_banks, cpu)[bank]->blocks);
1265 per_cpu(threshold_banks, cpu)[bank]->blocks = NULL;
1266 }
1267
1268 static void __threshold_remove_blocks(struct threshold_bank *b)
1269 {
1270 struct threshold_block *pos = NULL;
1271 struct threshold_block *tmp = NULL;
1272
1273 kobject_del(b->kobj);
1274
1275 list_for_each_entry_safe(pos, tmp, &b->blocks->miscj, miscj)
1276 kobject_del(&pos->kobj);
1277 }
1278
1279 static void threshold_remove_bank(unsigned int cpu, int bank)
1280 {
1281 struct amd_northbridge *nb;
1282 struct threshold_bank *b;
1283
1284 b = per_cpu(threshold_banks, cpu)[bank];
1285 if (!b)
1286 return;
1287
1288 if (!b->blocks)
1289 goto free_out;
1290
1291 if (is_shared_bank(bank)) {
1292 if (!atomic_dec_and_test(&b->cpus)) {
1293 __threshold_remove_blocks(b);
1294 per_cpu(threshold_banks, cpu)[bank] = NULL;
1295 return;
1296 } else {
1297 /*
1298 * the last CPU on this node using the shared bank is
1299 * going away, remove that bank now.
1300 */
1301 nb = node_to_amd_nb(amd_get_nb_id(cpu));
1302 nb->bank4 = NULL;
1303 }
1304 }
1305
1306 deallocate_threshold_block(cpu, bank);
1307
1308 free_out:
1309 kobject_del(b->kobj);
1310 kobject_put(b->kobj);
1311 kfree(b);
1312 per_cpu(threshold_banks, cpu)[bank] = NULL;
1313 }
1314
1315 int mce_threshold_remove_device(unsigned int cpu)
1316 {
1317 unsigned int bank;
1318
1319 if (!thresholding_en)
1320 return 0;
1321
1322 for (bank = 0; bank < mca_cfg.banks; ++bank) {
1323 if (!(per_cpu(bank_map, cpu) & (1 << bank)))
1324 continue;
1325 threshold_remove_bank(cpu, bank);
1326 }
1327 kfree(per_cpu(threshold_banks, cpu));
1328 per_cpu(threshold_banks, cpu) = NULL;
1329 return 0;
1330 }
1331
1332 /* create dir/files for all valid threshold banks */
1333 int mce_threshold_create_device(unsigned int cpu)
1334 {
1335 unsigned int bank;
1336 struct threshold_bank **bp;
1337 int err = 0;
1338
1339 if (!thresholding_en)
1340 return 0;
1341
1342 bp = per_cpu(threshold_banks, cpu);
1343 if (bp)
1344 return 0;
1345
1346 bp = kzalloc(sizeof(struct threshold_bank *) * mca_cfg.banks,
1347 GFP_KERNEL);
1348 if (!bp)
1349 return -ENOMEM;
1350
1351 per_cpu(threshold_banks, cpu) = bp;
1352
1353 for (bank = 0; bank < mca_cfg.banks; ++bank) {
1354 if (!(per_cpu(bank_map, cpu) & (1 << bank)))
1355 continue;
1356 err = threshold_create_bank(cpu, bank);
1357 if (err)
1358 goto err;
1359 }
1360 return err;
1361 err:
1362 mce_threshold_remove_device(cpu);
1363 return err;
1364 }
1365
1366 static __init int threshold_init_device(void)
1367 {
1368 unsigned lcpu = 0;
1369
1370 if (mce_threshold_vector == amd_threshold_interrupt)
1371 thresholding_en = true;
1372
1373 /* to hit CPUs online before the notifier is up */
1374 for_each_online_cpu(lcpu) {
1375 int err = mce_threshold_create_device(lcpu);
1376
1377 if (err)
1378 return err;
1379 }
1380
1381 return 0;
1382 }
1383 /*
1384 * there are 3 funcs which need to be _initcalled in a logic sequence:
1385 * 1. xen_late_init_mcelog
1386 * 2. mcheck_init_device
1387 * 3. threshold_init_device
1388 *
1389 * xen_late_init_mcelog must register xen_mce_chrdev_device before
1390 * native mce_chrdev_device registration if running under xen platform;
1391 *
1392 * mcheck_init_device should be inited before threshold_init_device to
1393 * initialize mce_device, otherwise a NULL ptr dereference will cause panic.
1394 *
1395 * so we use following _initcalls
1396 * 1. device_initcall(xen_late_init_mcelog);
1397 * 2. device_initcall_sync(mcheck_init_device);
1398 * 3. late_initcall(threshold_init_device);
1399 *
1400 * when running under xen, the initcall order is 1,2,3;
1401 * on baremetal, we skip 1 and we do only 2 and 3.
1402 */
1403 late_initcall(threshold_init_device);