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1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/export.h>
3#include <linux/bitops.h>
4#include <linux/elf.h>
5#include <linux/mm.h>
6
7#include <linux/io.h>
8#include <linux/sched.h>
9#include <linux/sched/clock.h>
10#include <linux/random.h>
11#include <linux/topology.h>
12#include <asm/processor.h>
13#include <asm/apic.h>
14#include <asm/cacheinfo.h>
15#include <asm/cpu.h>
16#include <asm/spec-ctrl.h>
17#include <asm/smp.h>
18#include <asm/numa.h>
19#include <asm/pci-direct.h>
20#include <asm/delay.h>
21#include <asm/debugreg.h>
22#include <asm/resctrl.h>
23
24#ifdef CONFIG_X86_64
25# include <asm/mmconfig.h>
26#endif
27
28#include "cpu.h"
29
30/*
31 * nodes_per_socket: Stores the number of nodes per socket.
32 * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
33 * Node Identifiers[10:8]
34 */
35static u32 nodes_per_socket = 1;
36
37static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
38{
39 u32 gprs[8] = { 0 };
40 int err;
41
42 WARN_ONCE((boot_cpu_data.x86 != 0xf),
43 "%s should only be used on K8!\n", __func__);
44
45 gprs[1] = msr;
46 gprs[7] = 0x9c5a203a;
47
48 err = rdmsr_safe_regs(gprs);
49
50 *p = gprs[0] | ((u64)gprs[2] << 32);
51
52 return err;
53}
54
55static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
56{
57 u32 gprs[8] = { 0 };
58
59 WARN_ONCE((boot_cpu_data.x86 != 0xf),
60 "%s should only be used on K8!\n", __func__);
61
62 gprs[0] = (u32)val;
63 gprs[1] = msr;
64 gprs[2] = val >> 32;
65 gprs[7] = 0x9c5a203a;
66
67 return wrmsr_safe_regs(gprs);
68}
69
70/*
71 * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
72 * misexecution of code under Linux. Owners of such processors should
73 * contact AMD for precise details and a CPU swap.
74 *
75 * See http://www.multimania.com/poulot/k6bug.html
76 * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
77 * (Publication # 21266 Issue Date: August 1998)
78 *
79 * The following test is erm.. interesting. AMD neglected to up
80 * the chip setting when fixing the bug but they also tweaked some
81 * performance at the same time..
82 */
83
84#ifdef CONFIG_X86_32
85extern __visible void vide(void);
86__asm__(".text\n"
87 ".globl vide\n"
88 ".type vide, @function\n"
89 ".align 4\n"
90 "vide: ret\n");
91#endif
92
93static void init_amd_k5(struct cpuinfo_x86 *c)
94{
95#ifdef CONFIG_X86_32
96/*
97 * General Systems BIOSen alias the cpu frequency registers
98 * of the Elan at 0x000df000. Unfortunately, one of the Linux
99 * drivers subsequently pokes it, and changes the CPU speed.
100 * Workaround : Remove the unneeded alias.
101 */
102#define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
103#define CBAR_ENB (0x80000000)
104#define CBAR_KEY (0X000000CB)
105 if (c->x86_model == 9 || c->x86_model == 10) {
106 if (inl(CBAR) & CBAR_ENB)
107 outl(0 | CBAR_KEY, CBAR);
108 }
109#endif
110}
111
112static void init_amd_k6(struct cpuinfo_x86 *c)
113{
114#ifdef CONFIG_X86_32
115 u32 l, h;
116 int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
117
118 if (c->x86_model < 6) {
119 /* Based on AMD doc 20734R - June 2000 */
120 if (c->x86_model == 0) {
121 clear_cpu_cap(c, X86_FEATURE_APIC);
122 set_cpu_cap(c, X86_FEATURE_PGE);
123 }
124 return;
125 }
126
127 if (c->x86_model == 6 && c->x86_stepping == 1) {
128 const int K6_BUG_LOOP = 1000000;
129 int n;
130 void (*f_vide)(void);
131 u64 d, d2;
132
133 pr_info("AMD K6 stepping B detected - ");
134
135 /*
136 * It looks like AMD fixed the 2.6.2 bug and improved indirect
137 * calls at the same time.
138 */
139
140 n = K6_BUG_LOOP;
141 f_vide = vide;
142 OPTIMIZER_HIDE_VAR(f_vide);
143 d = rdtsc();
144 while (n--)
145 f_vide();
146 d2 = rdtsc();
147 d = d2-d;
148
149 if (d > 20*K6_BUG_LOOP)
150 pr_cont("system stability may be impaired when more than 32 MB are used.\n");
151 else
152 pr_cont("probably OK (after B9730xxxx).\n");
153 }
154
155 /* K6 with old style WHCR */
156 if (c->x86_model < 8 ||
157 (c->x86_model == 8 && c->x86_stepping < 8)) {
158 /* We can only write allocate on the low 508Mb */
159 if (mbytes > 508)
160 mbytes = 508;
161
162 rdmsr(MSR_K6_WHCR, l, h);
163 if ((l&0x0000FFFF) == 0) {
164 unsigned long flags;
165 l = (1<<0)|((mbytes/4)<<1);
166 local_irq_save(flags);
167 wbinvd();
168 wrmsr(MSR_K6_WHCR, l, h);
169 local_irq_restore(flags);
170 pr_info("Enabling old style K6 write allocation for %d Mb\n",
171 mbytes);
172 }
173 return;
174 }
175
176 if ((c->x86_model == 8 && c->x86_stepping > 7) ||
177 c->x86_model == 9 || c->x86_model == 13) {
178 /* The more serious chips .. */
179
180 if (mbytes > 4092)
181 mbytes = 4092;
182
183 rdmsr(MSR_K6_WHCR, l, h);
184 if ((l&0xFFFF0000) == 0) {
185 unsigned long flags;
186 l = ((mbytes>>2)<<22)|(1<<16);
187 local_irq_save(flags);
188 wbinvd();
189 wrmsr(MSR_K6_WHCR, l, h);
190 local_irq_restore(flags);
191 pr_info("Enabling new style K6 write allocation for %d Mb\n",
192 mbytes);
193 }
194
195 return;
196 }
197
198 if (c->x86_model == 10) {
199 /* AMD Geode LX is model 10 */
200 /* placeholder for any needed mods */
201 return;
202 }
203#endif
204}
205
206static void init_amd_k7(struct cpuinfo_x86 *c)
207{
208#ifdef CONFIG_X86_32
209 u32 l, h;
210
211 /*
212 * Bit 15 of Athlon specific MSR 15, needs to be 0
213 * to enable SSE on Palomino/Morgan/Barton CPU's.
214 * If the BIOS didn't enable it already, enable it here.
215 */
216 if (c->x86_model >= 6 && c->x86_model <= 10) {
217 if (!cpu_has(c, X86_FEATURE_XMM)) {
218 pr_info("Enabling disabled K7/SSE Support.\n");
219 msr_clear_bit(MSR_K7_HWCR, 15);
220 set_cpu_cap(c, X86_FEATURE_XMM);
221 }
222 }
223
224 /*
225 * It's been determined by AMD that Athlons since model 8 stepping 1
226 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
227 * As per AMD technical note 27212 0.2
228 */
229 if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
230 rdmsr(MSR_K7_CLK_CTL, l, h);
231 if ((l & 0xfff00000) != 0x20000000) {
232 pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
233 l, ((l & 0x000fffff)|0x20000000));
234 wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
235 }
236 }
237
238 /* calling is from identify_secondary_cpu() ? */
239 if (!c->cpu_index)
240 return;
241
242 /*
243 * Certain Athlons might work (for various values of 'work') in SMP
244 * but they are not certified as MP capable.
245 */
246 /* Athlon 660/661 is valid. */
247 if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
248 (c->x86_stepping == 1)))
249 return;
250
251 /* Duron 670 is valid */
252 if ((c->x86_model == 7) && (c->x86_stepping == 0))
253 return;
254
255 /*
256 * Athlon 662, Duron 671, and Athlon >model 7 have capability
257 * bit. It's worth noting that the A5 stepping (662) of some
258 * Athlon XP's have the MP bit set.
259 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
260 * more.
261 */
262 if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
263 ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
264 (c->x86_model > 7))
265 if (cpu_has(c, X86_FEATURE_MP))
266 return;
267
268 /* If we get here, not a certified SMP capable AMD system. */
269
270 /*
271 * Don't taint if we are running SMP kernel on a single non-MP
272 * approved Athlon
273 */
274 WARN_ONCE(1, "WARNING: This combination of AMD"
275 " processors is not suitable for SMP.\n");
276 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
277#endif
278}
279
280#ifdef CONFIG_NUMA
281/*
282 * To workaround broken NUMA config. Read the comment in
283 * srat_detect_node().
284 */
285static int nearby_node(int apicid)
286{
287 int i, node;
288
289 for (i = apicid - 1; i >= 0; i--) {
290 node = __apicid_to_node[i];
291 if (node != NUMA_NO_NODE && node_online(node))
292 return node;
293 }
294 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
295 node = __apicid_to_node[i];
296 if (node != NUMA_NO_NODE && node_online(node))
297 return node;
298 }
299 return first_node(node_online_map); /* Shouldn't happen */
300}
301#endif
302
303/*
304 * Fix up topo::core_id for pre-F17h systems to be in the
305 * [0 .. cores_per_node - 1] range. Not really needed but
306 * kept so as not to break existing setups.
307 */
308static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
309{
310 u32 cus_per_node;
311
312 if (c->x86 >= 0x17)
313 return;
314
315 cus_per_node = c->x86_max_cores / nodes_per_socket;
316 c->topo.core_id %= cus_per_node;
317}
318
319/*
320 * Fixup core topology information for
321 * (1) AMD multi-node processors
322 * Assumption: Number of cores in each internal node is the same.
323 * (2) AMD processors supporting compute units
324 */
325static void amd_get_topology(struct cpuinfo_x86 *c)
326{
327 /* get information required for multi-node processors */
328 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
329 int err;
330 u32 eax, ebx, ecx, edx;
331
332 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
333
334 c->topo.die_id = ecx & 0xff;
335
336 if (c->x86 == 0x15)
337 c->topo.cu_id = ebx & 0xff;
338
339 if (c->x86 >= 0x17) {
340 c->topo.core_id = ebx & 0xff;
341
342 if (smp_num_siblings > 1)
343 c->x86_max_cores /= smp_num_siblings;
344 }
345
346 /*
347 * In case leaf B is available, use it to derive
348 * topology information.
349 */
350 err = detect_extended_topology(c);
351 if (!err)
352 c->x86_coreid_bits = get_count_order(c->x86_max_cores);
353
354 cacheinfo_amd_init_llc_id(c);
355
356 } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
357 u64 value;
358
359 rdmsrl(MSR_FAM10H_NODE_ID, value);
360 c->topo.die_id = value & 7;
361 c->topo.llc_id = c->topo.die_id;
362 } else
363 return;
364
365 if (nodes_per_socket > 1) {
366 set_cpu_cap(c, X86_FEATURE_AMD_DCM);
367 legacy_fixup_core_id(c);
368 }
369}
370
371/*
372 * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
373 * Assumes number of cores is a power of two.
374 */
375static void amd_detect_cmp(struct cpuinfo_x86 *c)
376{
377 unsigned bits;
378
379 bits = c->x86_coreid_bits;
380 /* Low order bits define the core id (index of core in socket) */
381 c->topo.core_id = c->topo.initial_apicid & ((1 << bits)-1);
382 /* Convert the initial APIC ID into the socket ID */
383 c->topo.pkg_id = c->topo.initial_apicid >> bits;
384 /* use socket ID also for last level cache */
385 c->topo.llc_id = c->topo.die_id = c->topo.pkg_id;
386}
387
388u32 amd_get_nodes_per_socket(void)
389{
390 return nodes_per_socket;
391}
392EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
393
394static void srat_detect_node(struct cpuinfo_x86 *c)
395{
396#ifdef CONFIG_NUMA
397 int cpu = smp_processor_id();
398 int node;
399 unsigned apicid = c->topo.apicid;
400
401 node = numa_cpu_node(cpu);
402 if (node == NUMA_NO_NODE)
403 node = per_cpu_llc_id(cpu);
404
405 /*
406 * On multi-fabric platform (e.g. Numascale NumaChip) a
407 * platform-specific handler needs to be called to fixup some
408 * IDs of the CPU.
409 */
410 if (x86_cpuinit.fixup_cpu_id)
411 x86_cpuinit.fixup_cpu_id(c, node);
412
413 if (!node_online(node)) {
414 /*
415 * Two possibilities here:
416 *
417 * - The CPU is missing memory and no node was created. In
418 * that case try picking one from a nearby CPU.
419 *
420 * - The APIC IDs differ from the HyperTransport node IDs
421 * which the K8 northbridge parsing fills in. Assume
422 * they are all increased by a constant offset, but in
423 * the same order as the HT nodeids. If that doesn't
424 * result in a usable node fall back to the path for the
425 * previous case.
426 *
427 * This workaround operates directly on the mapping between
428 * APIC ID and NUMA node, assuming certain relationship
429 * between APIC ID, HT node ID and NUMA topology. As going
430 * through CPU mapping may alter the outcome, directly
431 * access __apicid_to_node[].
432 */
433 int ht_nodeid = c->topo.initial_apicid;
434
435 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
436 node = __apicid_to_node[ht_nodeid];
437 /* Pick a nearby node */
438 if (!node_online(node))
439 node = nearby_node(apicid);
440 }
441 numa_set_node(cpu, node);
442#endif
443}
444
445static void early_init_amd_mc(struct cpuinfo_x86 *c)
446{
447#ifdef CONFIG_SMP
448 unsigned bits, ecx;
449
450 /* Multi core CPU? */
451 if (c->extended_cpuid_level < 0x80000008)
452 return;
453
454 ecx = cpuid_ecx(0x80000008);
455
456 c->x86_max_cores = (ecx & 0xff) + 1;
457
458 /* CPU telling us the core id bits shift? */
459 bits = (ecx >> 12) & 0xF;
460
461 /* Otherwise recompute */
462 if (bits == 0) {
463 while ((1 << bits) < c->x86_max_cores)
464 bits++;
465 }
466
467 c->x86_coreid_bits = bits;
468#endif
469}
470
471static void bsp_init_amd(struct cpuinfo_x86 *c)
472{
473 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
474
475 if (c->x86 > 0x10 ||
476 (c->x86 == 0x10 && c->x86_model >= 0x2)) {
477 u64 val;
478
479 rdmsrl(MSR_K7_HWCR, val);
480 if (!(val & BIT(24)))
481 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
482 }
483 }
484
485 if (c->x86 == 0x15) {
486 unsigned long upperbit;
487 u32 cpuid, assoc;
488
489 cpuid = cpuid_edx(0x80000005);
490 assoc = cpuid >> 16 & 0xff;
491 upperbit = ((cpuid >> 24) << 10) / assoc;
492
493 va_align.mask = (upperbit - 1) & PAGE_MASK;
494 va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
495
496 /* A random value per boot for bit slice [12:upper_bit) */
497 va_align.bits = get_random_u32() & va_align.mask;
498 }
499
500 if (cpu_has(c, X86_FEATURE_MWAITX))
501 use_mwaitx_delay();
502
503 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
504 u32 ecx;
505
506 ecx = cpuid_ecx(0x8000001e);
507 __max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
508 } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
509 u64 value;
510
511 rdmsrl(MSR_FAM10H_NODE_ID, value);
512 __max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
513 }
514
515 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
516 !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
517 c->x86 >= 0x15 && c->x86 <= 0x17) {
518 unsigned int bit;
519
520 switch (c->x86) {
521 case 0x15: bit = 54; break;
522 case 0x16: bit = 33; break;
523 case 0x17: bit = 10; break;
524 default: return;
525 }
526 /*
527 * Try to cache the base value so further operations can
528 * avoid RMW. If that faults, do not enable SSBD.
529 */
530 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
531 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
532 setup_force_cpu_cap(X86_FEATURE_SSBD);
533 x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
534 }
535 }
536
537 resctrl_cpu_detect(c);
538
539 /* Figure out Zen generations: */
540 switch (c->x86) {
541 case 0x17:
542 switch (c->x86_model) {
543 case 0x00 ... 0x2f:
544 case 0x50 ... 0x5f:
545 setup_force_cpu_cap(X86_FEATURE_ZEN1);
546 break;
547 case 0x30 ... 0x4f:
548 case 0x60 ... 0x7f:
549 case 0x90 ... 0x91:
550 case 0xa0 ... 0xaf:
551 setup_force_cpu_cap(X86_FEATURE_ZEN2);
552 break;
553 default:
554 goto warn;
555 }
556 break;
557
558 case 0x19:
559 switch (c->x86_model) {
560 case 0x00 ... 0x0f:
561 case 0x20 ... 0x5f:
562 setup_force_cpu_cap(X86_FEATURE_ZEN3);
563 break;
564 case 0x10 ... 0x1f:
565 case 0x60 ... 0xaf:
566 setup_force_cpu_cap(X86_FEATURE_ZEN4);
567 break;
568 default:
569 goto warn;
570 }
571 break;
572
573 case 0x1a:
574 switch (c->x86_model) {
575 case 0x00 ... 0x0f:
576 case 0x20 ... 0x2f:
577 case 0x40 ... 0x4f:
578 case 0x70 ... 0x7f:
579 setup_force_cpu_cap(X86_FEATURE_ZEN5);
580 break;
581 default:
582 goto warn;
583 }
584 break;
585
586 default:
587 break;
588 }
589
590 return;
591
592warn:
593 WARN_ONCE(1, "Family 0x%x, model: 0x%x??\n", c->x86, c->x86_model);
594}
595
596static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
597{
598 u64 msr;
599
600 /*
601 * BIOS support is required for SME and SEV.
602 * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
603 * the SME physical address space reduction value.
604 * If BIOS has not enabled SME then don't advertise the
605 * SME feature (set in scattered.c).
606 * If the kernel has not enabled SME via any means then
607 * don't advertise the SME feature.
608 * For SEV: If BIOS has not enabled SEV then don't advertise the
609 * SEV and SEV_ES feature (set in scattered.c).
610 *
611 * In all cases, since support for SME and SEV requires long mode,
612 * don't advertise the feature under CONFIG_X86_32.
613 */
614 if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
615 /* Check if memory encryption is enabled */
616 rdmsrl(MSR_AMD64_SYSCFG, msr);
617 if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
618 goto clear_all;
619
620 /*
621 * Always adjust physical address bits. Even though this
622 * will be a value above 32-bits this is still done for
623 * CONFIG_X86_32 so that accurate values are reported.
624 */
625 c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
626
627 if (IS_ENABLED(CONFIG_X86_32))
628 goto clear_all;
629
630 if (!sme_me_mask)
631 setup_clear_cpu_cap(X86_FEATURE_SME);
632
633 rdmsrl(MSR_K7_HWCR, msr);
634 if (!(msr & MSR_K7_HWCR_SMMLOCK))
635 goto clear_sev;
636
637 return;
638
639clear_all:
640 setup_clear_cpu_cap(X86_FEATURE_SME);
641clear_sev:
642 setup_clear_cpu_cap(X86_FEATURE_SEV);
643 setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
644 }
645}
646
647static void early_init_amd(struct cpuinfo_x86 *c)
648{
649 u64 value;
650 u32 dummy;
651
652 early_init_amd_mc(c);
653
654 if (c->x86 >= 0xf)
655 set_cpu_cap(c, X86_FEATURE_K8);
656
657 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
658
659 /*
660 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
661 * with P/T states and does not stop in deep C-states
662 */
663 if (c->x86_power & (1 << 8)) {
664 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
665 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
666 }
667
668 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
669 if (c->x86_power & BIT(12))
670 set_cpu_cap(c, X86_FEATURE_ACC_POWER);
671
672 /* Bit 14 indicates the Runtime Average Power Limit interface. */
673 if (c->x86_power & BIT(14))
674 set_cpu_cap(c, X86_FEATURE_RAPL);
675
676#ifdef CONFIG_X86_64
677 set_cpu_cap(c, X86_FEATURE_SYSCALL32);
678#else
679 /* Set MTRR capability flag if appropriate */
680 if (c->x86 == 5)
681 if (c->x86_model == 13 || c->x86_model == 9 ||
682 (c->x86_model == 8 && c->x86_stepping >= 8))
683 set_cpu_cap(c, X86_FEATURE_K6_MTRR);
684#endif
685#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
686 /*
687 * ApicID can always be treated as an 8-bit value for AMD APIC versions
688 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
689 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
690 * after 16h.
691 */
692 if (boot_cpu_has(X86_FEATURE_APIC)) {
693 if (c->x86 > 0x16)
694 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
695 else if (c->x86 >= 0xf) {
696 /* check CPU config space for extended APIC ID */
697 unsigned int val;
698
699 val = read_pci_config(0, 24, 0, 0x68);
700 if ((val >> 17 & 0x3) == 0x3)
701 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
702 }
703 }
704#endif
705
706 /*
707 * This is only needed to tell the kernel whether to use VMCALL
708 * and VMMCALL. VMMCALL is never executed except under virt, so
709 * we can set it unconditionally.
710 */
711 set_cpu_cap(c, X86_FEATURE_VMMCALL);
712
713 /* F16h erratum 793, CVE-2013-6885 */
714 if (c->x86 == 0x16 && c->x86_model <= 0xf)
715 msr_set_bit(MSR_AMD64_LS_CFG, 15);
716
717 early_detect_mem_encrypt(c);
718
719 /* Re-enable TopologyExtensions if switched off by BIOS */
720 if (c->x86 == 0x15 &&
721 (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
722 !cpu_has(c, X86_FEATURE_TOPOEXT)) {
723
724 if (msr_set_bit(0xc0011005, 54) > 0) {
725 rdmsrl(0xc0011005, value);
726 if (value & BIT_64(54)) {
727 set_cpu_cap(c, X86_FEATURE_TOPOEXT);
728 pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
729 }
730 }
731 }
732
733 if (cpu_has(c, X86_FEATURE_TOPOEXT))
734 smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
735
736 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
737 if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
738 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
739 else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
740 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
741 setup_force_cpu_cap(X86_FEATURE_SBPB);
742 }
743 }
744}
745
746static void init_amd_k8(struct cpuinfo_x86 *c)
747{
748 u32 level;
749 u64 value;
750
751 /* On C+ stepping K8 rep microcode works well for copy/memset */
752 level = cpuid_eax(1);
753 if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
754 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
755
756 /*
757 * Some BIOSes incorrectly force this feature, but only K8 revision D
758 * (model = 0x14) and later actually support it.
759 * (AMD Erratum #110, docId: 25759).
760 */
761 if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
762 clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
763 if (!rdmsrl_amd_safe(0xc001100d, &value)) {
764 value &= ~BIT_64(32);
765 wrmsrl_amd_safe(0xc001100d, value);
766 }
767 }
768
769 if (!c->x86_model_id[0])
770 strcpy(c->x86_model_id, "Hammer");
771
772#ifdef CONFIG_SMP
773 /*
774 * Disable TLB flush filter by setting HWCR.FFDIS on K8
775 * bit 6 of msr C001_0015
776 *
777 * Errata 63 for SH-B3 steppings
778 * Errata 122 for all steppings (F+ have it disabled by default)
779 */
780 msr_set_bit(MSR_K7_HWCR, 6);
781#endif
782 set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
783
784 /*
785 * Check models and steppings affected by erratum 400. This is
786 * used to select the proper idle routine and to enable the
787 * check whether the machine is affected in arch_post_acpi_subsys_init()
788 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
789 */
790 if (c->x86_model > 0x41 ||
791 (c->x86_model == 0x41 && c->x86_stepping >= 0x2))
792 setup_force_cpu_bug(X86_BUG_AMD_E400);
793}
794
795static void init_amd_gh(struct cpuinfo_x86 *c)
796{
797#ifdef CONFIG_MMCONF_FAM10H
798 /* do this for boot cpu */
799 if (c == &boot_cpu_data)
800 check_enable_amd_mmconf_dmi();
801
802 fam10h_check_enable_mmcfg();
803#endif
804
805 /*
806 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
807 * is always needed when GART is enabled, even in a kernel which has no
808 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
809 * If it doesn't, we do it here as suggested by the BKDG.
810 *
811 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
812 */
813 msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
814
815 /*
816 * On family 10h BIOS may not have properly enabled WC+ support, causing
817 * it to be converted to CD memtype. This may result in performance
818 * degradation for certain nested-paging guests. Prevent this conversion
819 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
820 *
821 * NOTE: we want to use the _safe accessors so as not to #GP kvm
822 * guests on older kvm hosts.
823 */
824 msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
825
826 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
827
828 /*
829 * Check models and steppings affected by erratum 400. This is
830 * used to select the proper idle routine and to enable the
831 * check whether the machine is affected in arch_post_acpi_subsys_init()
832 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
833 */
834 if (c->x86_model > 0x2 ||
835 (c->x86_model == 0x2 && c->x86_stepping >= 0x1))
836 setup_force_cpu_bug(X86_BUG_AMD_E400);
837}
838
839static void init_amd_ln(struct cpuinfo_x86 *c)
840{
841 /*
842 * Apply erratum 665 fix unconditionally so machines without a BIOS
843 * fix work.
844 */
845 msr_set_bit(MSR_AMD64_DE_CFG, 31);
846}
847
848static bool rdrand_force;
849
850static int __init rdrand_cmdline(char *str)
851{
852 if (!str)
853 return -EINVAL;
854
855 if (!strcmp(str, "force"))
856 rdrand_force = true;
857 else
858 return -EINVAL;
859
860 return 0;
861}
862early_param("rdrand", rdrand_cmdline);
863
864static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
865{
866 /*
867 * Saving of the MSR used to hide the RDRAND support during
868 * suspend/resume is done by arch/x86/power/cpu.c, which is
869 * dependent on CONFIG_PM_SLEEP.
870 */
871 if (!IS_ENABLED(CONFIG_PM_SLEEP))
872 return;
873
874 /*
875 * The self-test can clear X86_FEATURE_RDRAND, so check for
876 * RDRAND support using the CPUID function directly.
877 */
878 if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
879 return;
880
881 msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
882
883 /*
884 * Verify that the CPUID change has occurred in case the kernel is
885 * running virtualized and the hypervisor doesn't support the MSR.
886 */
887 if (cpuid_ecx(1) & BIT(30)) {
888 pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
889 return;
890 }
891
892 clear_cpu_cap(c, X86_FEATURE_RDRAND);
893 pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
894}
895
896static void init_amd_jg(struct cpuinfo_x86 *c)
897{
898 /*
899 * Some BIOS implementations do not restore proper RDRAND support
900 * across suspend and resume. Check on whether to hide the RDRAND
901 * instruction support via CPUID.
902 */
903 clear_rdrand_cpuid_bit(c);
904}
905
906static void init_amd_bd(struct cpuinfo_x86 *c)
907{
908 u64 value;
909
910 /*
911 * The way access filter has a performance penalty on some workloads.
912 * Disable it on the affected CPUs.
913 */
914 if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
915 if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
916 value |= 0x1E;
917 wrmsrl_safe(MSR_F15H_IC_CFG, value);
918 }
919 }
920
921 /*
922 * Some BIOS implementations do not restore proper RDRAND support
923 * across suspend and resume. Check on whether to hide the RDRAND
924 * instruction support via CPUID.
925 */
926 clear_rdrand_cpuid_bit(c);
927}
928
929static void fix_erratum_1386(struct cpuinfo_x86 *c)
930{
931 /*
932 * Work around Erratum 1386. The XSAVES instruction malfunctions in
933 * certain circumstances on Zen1/2 uarch, and not all parts have had
934 * updated microcode at the time of writing (March 2023).
935 *
936 * Affected parts all have no supervisor XSAVE states, meaning that
937 * the XSAVEC instruction (which works fine) is equivalent.
938 */
939 clear_cpu_cap(c, X86_FEATURE_XSAVES);
940}
941
942void init_spectral_chicken(struct cpuinfo_x86 *c)
943{
944#ifdef CONFIG_CPU_UNRET_ENTRY
945 u64 value;
946
947 /*
948 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
949 *
950 * This suppresses speculation from the middle of a basic block, i.e. it
951 * suppresses non-branch predictions.
952 */
953 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
954 if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
955 value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
956 wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
957 }
958 }
959#endif
960}
961
962static void init_amd_zen_common(void)
963{
964 setup_force_cpu_cap(X86_FEATURE_ZEN);
965#ifdef CONFIG_NUMA
966 node_reclaim_distance = 32;
967#endif
968}
969
970static void init_amd_zen1(struct cpuinfo_x86 *c)
971{
972 init_amd_zen_common();
973 fix_erratum_1386(c);
974
975 /* Fix up CPUID bits, but only if not virtualised. */
976 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
977
978 /* Erratum 1076: CPB feature bit not being set in CPUID. */
979 if (!cpu_has(c, X86_FEATURE_CPB))
980 set_cpu_cap(c, X86_FEATURE_CPB);
981 }
982
983 pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
984 setup_force_cpu_bug(X86_BUG_DIV0);
985}
986
987static bool cpu_has_zenbleed_microcode(void)
988{
989 u32 good_rev = 0;
990
991 switch (boot_cpu_data.x86_model) {
992 case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
993 case 0x60 ... 0x67: good_rev = 0x0860010b; break;
994 case 0x68 ... 0x6f: good_rev = 0x08608105; break;
995 case 0x70 ... 0x7f: good_rev = 0x08701032; break;
996 case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
997
998 default:
999 return false;
1000 }
1001
1002 if (boot_cpu_data.microcode < good_rev)
1003 return false;
1004
1005 return true;
1006}
1007
1008static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
1009{
1010 if (cpu_has(c, X86_FEATURE_HYPERVISOR))
1011 return;
1012
1013 if (!cpu_has(c, X86_FEATURE_AVX))
1014 return;
1015
1016 if (!cpu_has_zenbleed_microcode()) {
1017 pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
1018 msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1019 } else {
1020 msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1021 }
1022}
1023
1024static void init_amd_zen2(struct cpuinfo_x86 *c)
1025{
1026 init_amd_zen_common();
1027 init_spectral_chicken(c);
1028 fix_erratum_1386(c);
1029 zen2_zenbleed_check(c);
1030}
1031
1032static void init_amd_zen3(struct cpuinfo_x86 *c)
1033{
1034 init_amd_zen_common();
1035
1036 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
1037 /*
1038 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
1039 * Branch Type Confusion, but predate the allocation of the
1040 * BTC_NO bit.
1041 */
1042 if (!cpu_has(c, X86_FEATURE_BTC_NO))
1043 set_cpu_cap(c, X86_FEATURE_BTC_NO);
1044 }
1045}
1046
1047static void init_amd_zen4(struct cpuinfo_x86 *c)
1048{
1049 init_amd_zen_common();
1050
1051 if (!cpu_has(c, X86_FEATURE_HYPERVISOR))
1052 msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
1053}
1054
1055static void init_amd_zen5(struct cpuinfo_x86 *c)
1056{
1057 init_amd_zen_common();
1058}
1059
1060static void init_amd(struct cpuinfo_x86 *c)
1061{
1062 u64 vm_cr;
1063
1064 early_init_amd(c);
1065
1066 /*
1067 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
1068 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
1069 */
1070 clear_cpu_cap(c, 0*32+31);
1071
1072 if (c->x86 >= 0x10)
1073 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
1074
1075 /* AMD FSRM also implies FSRS */
1076 if (cpu_has(c, X86_FEATURE_FSRM))
1077 set_cpu_cap(c, X86_FEATURE_FSRS);
1078
1079 /* get apicid instead of initial apic id from cpuid */
1080 c->topo.apicid = read_apic_id();
1081
1082 /* K6s reports MCEs but don't actually have all the MSRs */
1083 if (c->x86 < 6)
1084 clear_cpu_cap(c, X86_FEATURE_MCE);
1085
1086 switch (c->x86) {
1087 case 4: init_amd_k5(c); break;
1088 case 5: init_amd_k6(c); break;
1089 case 6: init_amd_k7(c); break;
1090 case 0xf: init_amd_k8(c); break;
1091 case 0x10: init_amd_gh(c); break;
1092 case 0x12: init_amd_ln(c); break;
1093 case 0x15: init_amd_bd(c); break;
1094 case 0x16: init_amd_jg(c); break;
1095 }
1096
1097 if (boot_cpu_has(X86_FEATURE_ZEN1))
1098 init_amd_zen1(c);
1099 else if (boot_cpu_has(X86_FEATURE_ZEN2))
1100 init_amd_zen2(c);
1101 else if (boot_cpu_has(X86_FEATURE_ZEN3))
1102 init_amd_zen3(c);
1103 else if (boot_cpu_has(X86_FEATURE_ZEN4))
1104 init_amd_zen4(c);
1105 else if (boot_cpu_has(X86_FEATURE_ZEN5))
1106 init_amd_zen5(c);
1107
1108 /*
1109 * Enable workaround for FXSAVE leak on CPUs
1110 * without a XSaveErPtr feature
1111 */
1112 if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
1113 set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
1114
1115 cpu_detect_cache_sizes(c);
1116
1117 amd_detect_cmp(c);
1118 amd_get_topology(c);
1119 srat_detect_node(c);
1120
1121 init_amd_cacheinfo(c);
1122
1123 if (cpu_has(c, X86_FEATURE_SVM)) {
1124 rdmsrl(MSR_VM_CR, vm_cr);
1125 if (vm_cr & SVM_VM_CR_SVM_DIS_MASK) {
1126 pr_notice_once("SVM disabled (by BIOS) in MSR_VM_CR\n");
1127 clear_cpu_cap(c, X86_FEATURE_SVM);
1128 }
1129 }
1130
1131 if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) {
1132 /*
1133 * Use LFENCE for execution serialization. On families which
1134 * don't have that MSR, LFENCE is already serializing.
1135 * msr_set_bit() uses the safe accessors, too, even if the MSR
1136 * is not present.
1137 */
1138 msr_set_bit(MSR_AMD64_DE_CFG,
1139 MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
1140
1141 /* A serializing LFENCE stops RDTSC speculation */
1142 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
1143 }
1144
1145 /*
1146 * Family 0x12 and above processors have APIC timer
1147 * running in deep C states.
1148 */
1149 if (c->x86 > 0x11)
1150 set_cpu_cap(c, X86_FEATURE_ARAT);
1151
1152 /* 3DNow or LM implies PREFETCHW */
1153 if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
1154 if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
1155 set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
1156
1157 /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
1158 if (!cpu_feature_enabled(X86_FEATURE_XENPV))
1159 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
1160
1161 /*
1162 * Turn on the Instructions Retired free counter on machines not
1163 * susceptible to erratum #1054 "Instructions Retired Performance
1164 * Counter May Be Inaccurate".
1165 */
1166 if (cpu_has(c, X86_FEATURE_IRPERF) &&
1167 (boot_cpu_has(X86_FEATURE_ZEN1) && c->x86_model > 0x2f))
1168 msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
1169
1170 check_null_seg_clears_base(c);
1171
1172 /*
1173 * Make sure EFER[AIBRSE - Automatic IBRS Enable] is set. The APs are brought up
1174 * using the trampoline code and as part of it, MSR_EFER gets prepared there in
1175 * order to be replicated onto them. Regardless, set it here again, if not set,
1176 * to protect against any future refactoring/code reorganization which might
1177 * miss setting this important bit.
1178 */
1179 if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
1180 cpu_has(c, X86_FEATURE_AUTOIBRS))
1181 WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
1182
1183 /* AMD CPUs don't need fencing after x2APIC/TSC_DEADLINE MSR writes. */
1184 clear_cpu_cap(c, X86_FEATURE_APIC_MSRS_FENCE);
1185}
1186
1187#ifdef CONFIG_X86_32
1188static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
1189{
1190 /* AMD errata T13 (order #21922) */
1191 if (c->x86 == 6) {
1192 /* Duron Rev A0 */
1193 if (c->x86_model == 3 && c->x86_stepping == 0)
1194 size = 64;
1195 /* Tbird rev A1/A2 */
1196 if (c->x86_model == 4 &&
1197 (c->x86_stepping == 0 || c->x86_stepping == 1))
1198 size = 256;
1199 }
1200 return size;
1201}
1202#endif
1203
1204static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1205{
1206 u32 ebx, eax, ecx, edx;
1207 u16 mask = 0xfff;
1208
1209 if (c->x86 < 0xf)
1210 return;
1211
1212 if (c->extended_cpuid_level < 0x80000006)
1213 return;
1214
1215 cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1216
1217 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1218 tlb_lli_4k[ENTRIES] = ebx & mask;
1219
1220 /*
1221 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1222 * characteristics from the CPUID function 0x80000005 instead.
1223 */
1224 if (c->x86 == 0xf) {
1225 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1226 mask = 0xff;
1227 }
1228
1229 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1230 if (!((eax >> 16) & mask))
1231 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1232 else
1233 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1234
1235 /* a 4M entry uses two 2M entries */
1236 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1237
1238 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1239 if (!(eax & mask)) {
1240 /* Erratum 658 */
1241 if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1242 tlb_lli_2m[ENTRIES] = 1024;
1243 } else {
1244 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1245 tlb_lli_2m[ENTRIES] = eax & 0xff;
1246 }
1247 } else
1248 tlb_lli_2m[ENTRIES] = eax & mask;
1249
1250 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1251}
1252
1253static const struct cpu_dev amd_cpu_dev = {
1254 .c_vendor = "AMD",
1255 .c_ident = { "AuthenticAMD" },
1256#ifdef CONFIG_X86_32
1257 .legacy_models = {
1258 { .family = 4, .model_names =
1259 {
1260 [3] = "486 DX/2",
1261 [7] = "486 DX/2-WB",
1262 [8] = "486 DX/4",
1263 [9] = "486 DX/4-WB",
1264 [14] = "Am5x86-WT",
1265 [15] = "Am5x86-WB"
1266 }
1267 },
1268 },
1269 .legacy_cache_size = amd_size_cache,
1270#endif
1271 .c_early_init = early_init_amd,
1272 .c_detect_tlb = cpu_detect_tlb_amd,
1273 .c_bsp_init = bsp_init_amd,
1274 .c_init = init_amd,
1275 .c_x86_vendor = X86_VENDOR_AMD,
1276};
1277
1278cpu_dev_register(amd_cpu_dev);
1279
1280static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[4], amd_dr_addr_mask);
1281
1282static unsigned int amd_msr_dr_addr_masks[] = {
1283 MSR_F16H_DR0_ADDR_MASK,
1284 MSR_F16H_DR1_ADDR_MASK,
1285 MSR_F16H_DR1_ADDR_MASK + 1,
1286 MSR_F16H_DR1_ADDR_MASK + 2
1287};
1288
1289void amd_set_dr_addr_mask(unsigned long mask, unsigned int dr)
1290{
1291 int cpu = smp_processor_id();
1292
1293 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1294 return;
1295
1296 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1297 return;
1298
1299 if (per_cpu(amd_dr_addr_mask, cpu)[dr] == mask)
1300 return;
1301
1302 wrmsr(amd_msr_dr_addr_masks[dr], mask, 0);
1303 per_cpu(amd_dr_addr_mask, cpu)[dr] = mask;
1304}
1305
1306unsigned long amd_get_dr_addr_mask(unsigned int dr)
1307{
1308 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1309 return 0;
1310
1311 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1312 return 0;
1313
1314 return per_cpu(amd_dr_addr_mask[dr], smp_processor_id());
1315}
1316EXPORT_SYMBOL_GPL(amd_get_dr_addr_mask);
1317
1318u32 amd_get_highest_perf(void)
1319{
1320 struct cpuinfo_x86 *c = &boot_cpu_data;
1321
1322 if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
1323 (c->x86_model >= 0x70 && c->x86_model < 0x80)))
1324 return 166;
1325
1326 if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
1327 (c->x86_model >= 0x40 && c->x86_model < 0x70)))
1328 return 166;
1329
1330 return 255;
1331}
1332EXPORT_SYMBOL_GPL(amd_get_highest_perf);
1333
1334static void zenbleed_check_cpu(void *unused)
1335{
1336 struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
1337
1338 zen2_zenbleed_check(c);
1339}
1340
1341void amd_check_microcode(void)
1342{
1343 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
1344 return;
1345
1346 on_each_cpu(zenbleed_check_cpu, NULL, 1);
1347}
1348
1349/*
1350 * Issue a DIV 0/1 insn to clear any division data from previous DIV
1351 * operations.
1352 */
1353void noinstr amd_clear_divider(void)
1354{
1355 asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
1356 :: "a" (0), "d" (0), "r" (1));
1357}
1358EXPORT_SYMBOL_GPL(amd_clear_divider);
1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/export.h>
3#include <linux/bitops.h>
4#include <linux/elf.h>
5#include <linux/mm.h>
6
7#include <linux/io.h>
8#include <linux/sched.h>
9#include <linux/sched/clock.h>
10#include <linux/random.h>
11#include <linux/topology.h>
12#include <asm/processor.h>
13#include <asm/apic.h>
14#include <asm/cacheinfo.h>
15#include <asm/cpu.h>
16#include <asm/cpu_device_id.h>
17#include <asm/spec-ctrl.h>
18#include <asm/smp.h>
19#include <asm/numa.h>
20#include <asm/pci-direct.h>
21#include <asm/delay.h>
22#include <asm/debugreg.h>
23#include <asm/resctrl.h>
24#include <asm/sev.h>
25
26#ifdef CONFIG_X86_64
27# include <asm/mmconfig.h>
28#endif
29
30#include "cpu.h"
31
32static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
33{
34 u32 gprs[8] = { 0 };
35 int err;
36
37 WARN_ONCE((boot_cpu_data.x86 != 0xf),
38 "%s should only be used on K8!\n", __func__);
39
40 gprs[1] = msr;
41 gprs[7] = 0x9c5a203a;
42
43 err = rdmsr_safe_regs(gprs);
44
45 *p = gprs[0] | ((u64)gprs[2] << 32);
46
47 return err;
48}
49
50static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
51{
52 u32 gprs[8] = { 0 };
53
54 WARN_ONCE((boot_cpu_data.x86 != 0xf),
55 "%s should only be used on K8!\n", __func__);
56
57 gprs[0] = (u32)val;
58 gprs[1] = msr;
59 gprs[2] = val >> 32;
60 gprs[7] = 0x9c5a203a;
61
62 return wrmsr_safe_regs(gprs);
63}
64
65/*
66 * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
67 * misexecution of code under Linux. Owners of such processors should
68 * contact AMD for precise details and a CPU swap.
69 *
70 * See http://www.multimania.com/poulot/k6bug.html
71 * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
72 * (Publication # 21266 Issue Date: August 1998)
73 *
74 * The following test is erm.. interesting. AMD neglected to up
75 * the chip setting when fixing the bug but they also tweaked some
76 * performance at the same time..
77 */
78
79#ifdef CONFIG_X86_32
80extern __visible void vide(void);
81__asm__(".text\n"
82 ".globl vide\n"
83 ".type vide, @function\n"
84 ".align 4\n"
85 "vide: ret\n");
86#endif
87
88static void init_amd_k5(struct cpuinfo_x86 *c)
89{
90#ifdef CONFIG_X86_32
91/*
92 * General Systems BIOSen alias the cpu frequency registers
93 * of the Elan at 0x000df000. Unfortunately, one of the Linux
94 * drivers subsequently pokes it, and changes the CPU speed.
95 * Workaround : Remove the unneeded alias.
96 */
97#define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
98#define CBAR_ENB (0x80000000)
99#define CBAR_KEY (0X000000CB)
100 if (c->x86_model == 9 || c->x86_model == 10) {
101 if (inl(CBAR) & CBAR_ENB)
102 outl(0 | CBAR_KEY, CBAR);
103 }
104#endif
105}
106
107static void init_amd_k6(struct cpuinfo_x86 *c)
108{
109#ifdef CONFIG_X86_32
110 u32 l, h;
111 int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
112
113 if (c->x86_model < 6) {
114 /* Based on AMD doc 20734R - June 2000 */
115 if (c->x86_model == 0) {
116 clear_cpu_cap(c, X86_FEATURE_APIC);
117 set_cpu_cap(c, X86_FEATURE_PGE);
118 }
119 return;
120 }
121
122 if (c->x86_model == 6 && c->x86_stepping == 1) {
123 const int K6_BUG_LOOP = 1000000;
124 int n;
125 void (*f_vide)(void);
126 u64 d, d2;
127
128 pr_info("AMD K6 stepping B detected - ");
129
130 /*
131 * It looks like AMD fixed the 2.6.2 bug and improved indirect
132 * calls at the same time.
133 */
134
135 n = K6_BUG_LOOP;
136 f_vide = vide;
137 OPTIMIZER_HIDE_VAR(f_vide);
138 d = rdtsc();
139 while (n--)
140 f_vide();
141 d2 = rdtsc();
142 d = d2-d;
143
144 if (d > 20*K6_BUG_LOOP)
145 pr_cont("system stability may be impaired when more than 32 MB are used.\n");
146 else
147 pr_cont("probably OK (after B9730xxxx).\n");
148 }
149
150 /* K6 with old style WHCR */
151 if (c->x86_model < 8 ||
152 (c->x86_model == 8 && c->x86_stepping < 8)) {
153 /* We can only write allocate on the low 508Mb */
154 if (mbytes > 508)
155 mbytes = 508;
156
157 rdmsr(MSR_K6_WHCR, l, h);
158 if ((l&0x0000FFFF) == 0) {
159 unsigned long flags;
160 l = (1<<0)|((mbytes/4)<<1);
161 local_irq_save(flags);
162 wbinvd();
163 wrmsr(MSR_K6_WHCR, l, h);
164 local_irq_restore(flags);
165 pr_info("Enabling old style K6 write allocation for %d Mb\n",
166 mbytes);
167 }
168 return;
169 }
170
171 if ((c->x86_model == 8 && c->x86_stepping > 7) ||
172 c->x86_model == 9 || c->x86_model == 13) {
173 /* The more serious chips .. */
174
175 if (mbytes > 4092)
176 mbytes = 4092;
177
178 rdmsr(MSR_K6_WHCR, l, h);
179 if ((l&0xFFFF0000) == 0) {
180 unsigned long flags;
181 l = ((mbytes>>2)<<22)|(1<<16);
182 local_irq_save(flags);
183 wbinvd();
184 wrmsr(MSR_K6_WHCR, l, h);
185 local_irq_restore(flags);
186 pr_info("Enabling new style K6 write allocation for %d Mb\n",
187 mbytes);
188 }
189
190 return;
191 }
192
193 if (c->x86_model == 10) {
194 /* AMD Geode LX is model 10 */
195 /* placeholder for any needed mods */
196 return;
197 }
198#endif
199}
200
201static void init_amd_k7(struct cpuinfo_x86 *c)
202{
203#ifdef CONFIG_X86_32
204 u32 l, h;
205
206 /*
207 * Bit 15 of Athlon specific MSR 15, needs to be 0
208 * to enable SSE on Palomino/Morgan/Barton CPU's.
209 * If the BIOS didn't enable it already, enable it here.
210 */
211 if (c->x86_model >= 6 && c->x86_model <= 10) {
212 if (!cpu_has(c, X86_FEATURE_XMM)) {
213 pr_info("Enabling disabled K7/SSE Support.\n");
214 msr_clear_bit(MSR_K7_HWCR, 15);
215 set_cpu_cap(c, X86_FEATURE_XMM);
216 }
217 }
218
219 /*
220 * It's been determined by AMD that Athlons since model 8 stepping 1
221 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
222 * As per AMD technical note 27212 0.2
223 */
224 if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
225 rdmsr(MSR_K7_CLK_CTL, l, h);
226 if ((l & 0xfff00000) != 0x20000000) {
227 pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
228 l, ((l & 0x000fffff)|0x20000000));
229 wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
230 }
231 }
232
233 /* calling is from identify_secondary_cpu() ? */
234 if (!c->cpu_index)
235 return;
236
237 /*
238 * Certain Athlons might work (for various values of 'work') in SMP
239 * but they are not certified as MP capable.
240 */
241 /* Athlon 660/661 is valid. */
242 if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
243 (c->x86_stepping == 1)))
244 return;
245
246 /* Duron 670 is valid */
247 if ((c->x86_model == 7) && (c->x86_stepping == 0))
248 return;
249
250 /*
251 * Athlon 662, Duron 671, and Athlon >model 7 have capability
252 * bit. It's worth noting that the A5 stepping (662) of some
253 * Athlon XP's have the MP bit set.
254 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
255 * more.
256 */
257 if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
258 ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
259 (c->x86_model > 7))
260 if (cpu_has(c, X86_FEATURE_MP))
261 return;
262
263 /* If we get here, not a certified SMP capable AMD system. */
264
265 /*
266 * Don't taint if we are running SMP kernel on a single non-MP
267 * approved Athlon
268 */
269 WARN_ONCE(1, "WARNING: This combination of AMD"
270 " processors is not suitable for SMP.\n");
271 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
272#endif
273}
274
275#ifdef CONFIG_NUMA
276/*
277 * To workaround broken NUMA config. Read the comment in
278 * srat_detect_node().
279 */
280static int nearby_node(int apicid)
281{
282 int i, node;
283
284 for (i = apicid - 1; i >= 0; i--) {
285 node = __apicid_to_node[i];
286 if (node != NUMA_NO_NODE && node_online(node))
287 return node;
288 }
289 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
290 node = __apicid_to_node[i];
291 if (node != NUMA_NO_NODE && node_online(node))
292 return node;
293 }
294 return first_node(node_online_map); /* Shouldn't happen */
295}
296#endif
297
298static void srat_detect_node(struct cpuinfo_x86 *c)
299{
300#ifdef CONFIG_NUMA
301 int cpu = smp_processor_id();
302 int node;
303 unsigned apicid = c->topo.apicid;
304
305 node = numa_cpu_node(cpu);
306 if (node == NUMA_NO_NODE)
307 node = per_cpu_llc_id(cpu);
308
309 /*
310 * On multi-fabric platform (e.g. Numascale NumaChip) a
311 * platform-specific handler needs to be called to fixup some
312 * IDs of the CPU.
313 */
314 if (x86_cpuinit.fixup_cpu_id)
315 x86_cpuinit.fixup_cpu_id(c, node);
316
317 if (!node_online(node)) {
318 /*
319 * Two possibilities here:
320 *
321 * - The CPU is missing memory and no node was created. In
322 * that case try picking one from a nearby CPU.
323 *
324 * - The APIC IDs differ from the HyperTransport node IDs
325 * which the K8 northbridge parsing fills in. Assume
326 * they are all increased by a constant offset, but in
327 * the same order as the HT nodeids. If that doesn't
328 * result in a usable node fall back to the path for the
329 * previous case.
330 *
331 * This workaround operates directly on the mapping between
332 * APIC ID and NUMA node, assuming certain relationship
333 * between APIC ID, HT node ID and NUMA topology. As going
334 * through CPU mapping may alter the outcome, directly
335 * access __apicid_to_node[].
336 */
337 int ht_nodeid = c->topo.initial_apicid;
338
339 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
340 node = __apicid_to_node[ht_nodeid];
341 /* Pick a nearby node */
342 if (!node_online(node))
343 node = nearby_node(apicid);
344 }
345 numa_set_node(cpu, node);
346#endif
347}
348
349static void bsp_determine_snp(struct cpuinfo_x86 *c)
350{
351#ifdef CONFIG_ARCH_HAS_CC_PLATFORM
352 cc_vendor = CC_VENDOR_AMD;
353
354 if (cpu_has(c, X86_FEATURE_SEV_SNP)) {
355 /*
356 * RMP table entry format is not architectural and is defined by the
357 * per-processor PPR. Restrict SNP support on the known CPU models
358 * for which the RMP table entry format is currently defined for.
359 */
360 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
361 c->x86 >= 0x19 && snp_probe_rmptable_info()) {
362 cc_platform_set(CC_ATTR_HOST_SEV_SNP);
363 } else {
364 setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
365 cc_platform_clear(CC_ATTR_HOST_SEV_SNP);
366 }
367 }
368#endif
369}
370
371static void bsp_init_amd(struct cpuinfo_x86 *c)
372{
373 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
374
375 if (c->x86 > 0x10 ||
376 (c->x86 == 0x10 && c->x86_model >= 0x2)) {
377 u64 val;
378
379 rdmsrl(MSR_K7_HWCR, val);
380 if (!(val & BIT(24)))
381 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
382 }
383 }
384
385 if (c->x86 == 0x15) {
386 unsigned long upperbit;
387 u32 cpuid, assoc;
388
389 cpuid = cpuid_edx(0x80000005);
390 assoc = cpuid >> 16 & 0xff;
391 upperbit = ((cpuid >> 24) << 10) / assoc;
392
393 va_align.mask = (upperbit - 1) & PAGE_MASK;
394 va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
395
396 /* A random value per boot for bit slice [12:upper_bit) */
397 va_align.bits = get_random_u32() & va_align.mask;
398 }
399
400 if (cpu_has(c, X86_FEATURE_MWAITX))
401 use_mwaitx_delay();
402
403 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
404 !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
405 c->x86 >= 0x15 && c->x86 <= 0x17) {
406 unsigned int bit;
407
408 switch (c->x86) {
409 case 0x15: bit = 54; break;
410 case 0x16: bit = 33; break;
411 case 0x17: bit = 10; break;
412 default: return;
413 }
414 /*
415 * Try to cache the base value so further operations can
416 * avoid RMW. If that faults, do not enable SSBD.
417 */
418 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
419 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
420 setup_force_cpu_cap(X86_FEATURE_SSBD);
421 x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
422 }
423 }
424
425 resctrl_cpu_detect(c);
426
427 /* Figure out Zen generations: */
428 switch (c->x86) {
429 case 0x17:
430 switch (c->x86_model) {
431 case 0x00 ... 0x2f:
432 case 0x50 ... 0x5f:
433 setup_force_cpu_cap(X86_FEATURE_ZEN1);
434 break;
435 case 0x30 ... 0x4f:
436 case 0x60 ... 0x7f:
437 case 0x90 ... 0x91:
438 case 0xa0 ... 0xaf:
439 setup_force_cpu_cap(X86_FEATURE_ZEN2);
440 break;
441 default:
442 goto warn;
443 }
444 break;
445
446 case 0x19:
447 switch (c->x86_model) {
448 case 0x00 ... 0x0f:
449 case 0x20 ... 0x5f:
450 setup_force_cpu_cap(X86_FEATURE_ZEN3);
451 break;
452 case 0x10 ... 0x1f:
453 case 0x60 ... 0xaf:
454 setup_force_cpu_cap(X86_FEATURE_ZEN4);
455 break;
456 default:
457 goto warn;
458 }
459 break;
460
461 case 0x1a:
462 switch (c->x86_model) {
463 case 0x00 ... 0x2f:
464 case 0x40 ... 0x4f:
465 case 0x60 ... 0x7f:
466 setup_force_cpu_cap(X86_FEATURE_ZEN5);
467 break;
468 default:
469 goto warn;
470 }
471 break;
472
473 default:
474 break;
475 }
476
477 bsp_determine_snp(c);
478 return;
479
480warn:
481 WARN_ONCE(1, "Family 0x%x, model: 0x%x??\n", c->x86, c->x86_model);
482}
483
484static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
485{
486 u64 msr;
487
488 /*
489 * BIOS support is required for SME and SEV.
490 * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
491 * the SME physical address space reduction value.
492 * If BIOS has not enabled SME then don't advertise the
493 * SME feature (set in scattered.c).
494 * If the kernel has not enabled SME via any means then
495 * don't advertise the SME feature.
496 * For SEV: If BIOS has not enabled SEV then don't advertise SEV and
497 * any additional functionality based on it.
498 *
499 * In all cases, since support for SME and SEV requires long mode,
500 * don't advertise the feature under CONFIG_X86_32.
501 */
502 if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
503 /* Check if memory encryption is enabled */
504 rdmsrl(MSR_AMD64_SYSCFG, msr);
505 if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
506 goto clear_all;
507
508 /*
509 * Always adjust physical address bits. Even though this
510 * will be a value above 32-bits this is still done for
511 * CONFIG_X86_32 so that accurate values are reported.
512 */
513 c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
514
515 if (IS_ENABLED(CONFIG_X86_32))
516 goto clear_all;
517
518 if (!sme_me_mask)
519 setup_clear_cpu_cap(X86_FEATURE_SME);
520
521 rdmsrl(MSR_K7_HWCR, msr);
522 if (!(msr & MSR_K7_HWCR_SMMLOCK))
523 goto clear_sev;
524
525 return;
526
527clear_all:
528 setup_clear_cpu_cap(X86_FEATURE_SME);
529clear_sev:
530 setup_clear_cpu_cap(X86_FEATURE_SEV);
531 setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
532 setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
533 }
534}
535
536static void early_init_amd(struct cpuinfo_x86 *c)
537{
538 u32 dummy;
539
540 if (c->x86 >= 0xf)
541 set_cpu_cap(c, X86_FEATURE_K8);
542
543 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
544
545 /*
546 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
547 * with P/T states and does not stop in deep C-states
548 */
549 if (c->x86_power & (1 << 8)) {
550 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
551 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
552 }
553
554 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
555 if (c->x86_power & BIT(12))
556 set_cpu_cap(c, X86_FEATURE_ACC_POWER);
557
558 /* Bit 14 indicates the Runtime Average Power Limit interface. */
559 if (c->x86_power & BIT(14))
560 set_cpu_cap(c, X86_FEATURE_RAPL);
561
562#ifdef CONFIG_X86_64
563 set_cpu_cap(c, X86_FEATURE_SYSCALL32);
564#else
565 /* Set MTRR capability flag if appropriate */
566 if (c->x86 == 5)
567 if (c->x86_model == 13 || c->x86_model == 9 ||
568 (c->x86_model == 8 && c->x86_stepping >= 8))
569 set_cpu_cap(c, X86_FEATURE_K6_MTRR);
570#endif
571#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
572 /*
573 * ApicID can always be treated as an 8-bit value for AMD APIC versions
574 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
575 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
576 * after 16h.
577 */
578 if (boot_cpu_has(X86_FEATURE_APIC)) {
579 if (c->x86 > 0x16)
580 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
581 else if (c->x86 >= 0xf) {
582 /* check CPU config space for extended APIC ID */
583 unsigned int val;
584
585 val = read_pci_config(0, 24, 0, 0x68);
586 if ((val >> 17 & 0x3) == 0x3)
587 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
588 }
589 }
590#endif
591
592 /*
593 * This is only needed to tell the kernel whether to use VMCALL
594 * and VMMCALL. VMMCALL is never executed except under virt, so
595 * we can set it unconditionally.
596 */
597 set_cpu_cap(c, X86_FEATURE_VMMCALL);
598
599 /* F16h erratum 793, CVE-2013-6885 */
600 if (c->x86 == 0x16 && c->x86_model <= 0xf)
601 msr_set_bit(MSR_AMD64_LS_CFG, 15);
602
603 early_detect_mem_encrypt(c);
604
605 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
606 if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
607 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
608 else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
609 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
610 setup_force_cpu_cap(X86_FEATURE_SBPB);
611 }
612 }
613}
614
615static void init_amd_k8(struct cpuinfo_x86 *c)
616{
617 u32 level;
618 u64 value;
619
620 /* On C+ stepping K8 rep microcode works well for copy/memset */
621 level = cpuid_eax(1);
622 if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
623 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
624
625 /*
626 * Some BIOSes incorrectly force this feature, but only K8 revision D
627 * (model = 0x14) and later actually support it.
628 * (AMD Erratum #110, docId: 25759).
629 */
630 if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
631 clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
632 if (!rdmsrl_amd_safe(0xc001100d, &value)) {
633 value &= ~BIT_64(32);
634 wrmsrl_amd_safe(0xc001100d, value);
635 }
636 }
637
638 if (!c->x86_model_id[0])
639 strcpy(c->x86_model_id, "Hammer");
640
641#ifdef CONFIG_SMP
642 /*
643 * Disable TLB flush filter by setting HWCR.FFDIS on K8
644 * bit 6 of msr C001_0015
645 *
646 * Errata 63 for SH-B3 steppings
647 * Errata 122 for all steppings (F+ have it disabled by default)
648 */
649 msr_set_bit(MSR_K7_HWCR, 6);
650#endif
651 set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
652
653 /*
654 * Check models and steppings affected by erratum 400. This is
655 * used to select the proper idle routine and to enable the
656 * check whether the machine is affected in arch_post_acpi_subsys_init()
657 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
658 */
659 if (c->x86_model > 0x41 ||
660 (c->x86_model == 0x41 && c->x86_stepping >= 0x2))
661 setup_force_cpu_bug(X86_BUG_AMD_E400);
662}
663
664static void init_amd_gh(struct cpuinfo_x86 *c)
665{
666#ifdef CONFIG_MMCONF_FAM10H
667 /* do this for boot cpu */
668 if (c == &boot_cpu_data)
669 check_enable_amd_mmconf_dmi();
670
671 fam10h_check_enable_mmcfg();
672#endif
673
674 /*
675 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
676 * is always needed when GART is enabled, even in a kernel which has no
677 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
678 * If it doesn't, we do it here as suggested by the BKDG.
679 *
680 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
681 */
682 msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
683
684 /*
685 * On family 10h BIOS may not have properly enabled WC+ support, causing
686 * it to be converted to CD memtype. This may result in performance
687 * degradation for certain nested-paging guests. Prevent this conversion
688 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
689 *
690 * NOTE: we want to use the _safe accessors so as not to #GP kvm
691 * guests on older kvm hosts.
692 */
693 msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
694
695 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
696
697 /*
698 * Check models and steppings affected by erratum 400. This is
699 * used to select the proper idle routine and to enable the
700 * check whether the machine is affected in arch_post_acpi_subsys_init()
701 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
702 */
703 if (c->x86_model > 0x2 ||
704 (c->x86_model == 0x2 && c->x86_stepping >= 0x1))
705 setup_force_cpu_bug(X86_BUG_AMD_E400);
706}
707
708static void init_amd_ln(struct cpuinfo_x86 *c)
709{
710 /*
711 * Apply erratum 665 fix unconditionally so machines without a BIOS
712 * fix work.
713 */
714 msr_set_bit(MSR_AMD64_DE_CFG, 31);
715}
716
717static bool rdrand_force;
718
719static int __init rdrand_cmdline(char *str)
720{
721 if (!str)
722 return -EINVAL;
723
724 if (!strcmp(str, "force"))
725 rdrand_force = true;
726 else
727 return -EINVAL;
728
729 return 0;
730}
731early_param("rdrand", rdrand_cmdline);
732
733static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
734{
735 /*
736 * Saving of the MSR used to hide the RDRAND support during
737 * suspend/resume is done by arch/x86/power/cpu.c, which is
738 * dependent on CONFIG_PM_SLEEP.
739 */
740 if (!IS_ENABLED(CONFIG_PM_SLEEP))
741 return;
742
743 /*
744 * The self-test can clear X86_FEATURE_RDRAND, so check for
745 * RDRAND support using the CPUID function directly.
746 */
747 if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
748 return;
749
750 msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
751
752 /*
753 * Verify that the CPUID change has occurred in case the kernel is
754 * running virtualized and the hypervisor doesn't support the MSR.
755 */
756 if (cpuid_ecx(1) & BIT(30)) {
757 pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
758 return;
759 }
760
761 clear_cpu_cap(c, X86_FEATURE_RDRAND);
762 pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
763}
764
765static void init_amd_jg(struct cpuinfo_x86 *c)
766{
767 /*
768 * Some BIOS implementations do not restore proper RDRAND support
769 * across suspend and resume. Check on whether to hide the RDRAND
770 * instruction support via CPUID.
771 */
772 clear_rdrand_cpuid_bit(c);
773}
774
775static void init_amd_bd(struct cpuinfo_x86 *c)
776{
777 u64 value;
778
779 /*
780 * The way access filter has a performance penalty on some workloads.
781 * Disable it on the affected CPUs.
782 */
783 if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
784 if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
785 value |= 0x1E;
786 wrmsrl_safe(MSR_F15H_IC_CFG, value);
787 }
788 }
789
790 /*
791 * Some BIOS implementations do not restore proper RDRAND support
792 * across suspend and resume. Check on whether to hide the RDRAND
793 * instruction support via CPUID.
794 */
795 clear_rdrand_cpuid_bit(c);
796}
797
798static const struct x86_cpu_desc erratum_1386_microcode[] = {
799 AMD_CPU_DESC(0x17, 0x1, 0x2, 0x0800126e),
800 AMD_CPU_DESC(0x17, 0x31, 0x0, 0x08301052),
801 {},
802};
803
804static void fix_erratum_1386(struct cpuinfo_x86 *c)
805{
806 /*
807 * Work around Erratum 1386. The XSAVES instruction malfunctions in
808 * certain circumstances on Zen1/2 uarch, and not all parts have had
809 * updated microcode at the time of writing (March 2023).
810 *
811 * Affected parts all have no supervisor XSAVE states, meaning that
812 * the XSAVEC instruction (which works fine) is equivalent.
813 *
814 * Clear the feature flag only on microcode revisions which
815 * don't have the fix.
816 */
817 if (x86_cpu_has_min_microcode_rev(erratum_1386_microcode))
818 return;
819
820 clear_cpu_cap(c, X86_FEATURE_XSAVES);
821}
822
823void init_spectral_chicken(struct cpuinfo_x86 *c)
824{
825#ifdef CONFIG_MITIGATION_UNRET_ENTRY
826 u64 value;
827
828 /*
829 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
830 *
831 * This suppresses speculation from the middle of a basic block, i.e. it
832 * suppresses non-branch predictions.
833 */
834 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
835 if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
836 value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
837 wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
838 }
839 }
840#endif
841}
842
843static void init_amd_zen_common(void)
844{
845 setup_force_cpu_cap(X86_FEATURE_ZEN);
846#ifdef CONFIG_NUMA
847 node_reclaim_distance = 32;
848#endif
849}
850
851static void init_amd_zen1(struct cpuinfo_x86 *c)
852{
853 fix_erratum_1386(c);
854
855 /* Fix up CPUID bits, but only if not virtualised. */
856 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
857
858 /* Erratum 1076: CPB feature bit not being set in CPUID. */
859 if (!cpu_has(c, X86_FEATURE_CPB))
860 set_cpu_cap(c, X86_FEATURE_CPB);
861 }
862
863 pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
864 setup_force_cpu_bug(X86_BUG_DIV0);
865}
866
867static bool cpu_has_zenbleed_microcode(void)
868{
869 u32 good_rev = 0;
870
871 switch (boot_cpu_data.x86_model) {
872 case 0x30 ... 0x3f: good_rev = 0x0830107b; break;
873 case 0x60 ... 0x67: good_rev = 0x0860010c; break;
874 case 0x68 ... 0x6f: good_rev = 0x08608107; break;
875 case 0x70 ... 0x7f: good_rev = 0x08701033; break;
876 case 0xa0 ... 0xaf: good_rev = 0x08a00009; break;
877
878 default:
879 return false;
880 }
881
882 if (boot_cpu_data.microcode < good_rev)
883 return false;
884
885 return true;
886}
887
888static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
889{
890 if (cpu_has(c, X86_FEATURE_HYPERVISOR))
891 return;
892
893 if (!cpu_has(c, X86_FEATURE_AVX))
894 return;
895
896 if (!cpu_has_zenbleed_microcode()) {
897 pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
898 msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
899 } else {
900 msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
901 }
902}
903
904static void init_amd_zen2(struct cpuinfo_x86 *c)
905{
906 init_spectral_chicken(c);
907 fix_erratum_1386(c);
908 zen2_zenbleed_check(c);
909}
910
911static void init_amd_zen3(struct cpuinfo_x86 *c)
912{
913 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
914 /*
915 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
916 * Branch Type Confusion, but predate the allocation of the
917 * BTC_NO bit.
918 */
919 if (!cpu_has(c, X86_FEATURE_BTC_NO))
920 set_cpu_cap(c, X86_FEATURE_BTC_NO);
921 }
922}
923
924static void init_amd_zen4(struct cpuinfo_x86 *c)
925{
926 if (!cpu_has(c, X86_FEATURE_HYPERVISOR))
927 msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
928
929 /*
930 * These Zen4 SoCs advertise support for virtualized VMLOAD/VMSAVE
931 * in some BIOS versions but they can lead to random host reboots.
932 */
933 switch (c->x86_model) {
934 case 0x18 ... 0x1f:
935 case 0x60 ... 0x7f:
936 clear_cpu_cap(c, X86_FEATURE_V_VMSAVE_VMLOAD);
937 break;
938 }
939}
940
941static void init_amd_zen5(struct cpuinfo_x86 *c)
942{
943}
944
945static void init_amd(struct cpuinfo_x86 *c)
946{
947 u64 vm_cr;
948
949 early_init_amd(c);
950
951 /*
952 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
953 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
954 */
955 clear_cpu_cap(c, 0*32+31);
956
957 if (c->x86 >= 0x10)
958 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
959
960 /* AMD FSRM also implies FSRS */
961 if (cpu_has(c, X86_FEATURE_FSRM))
962 set_cpu_cap(c, X86_FEATURE_FSRS);
963
964 /* K6s reports MCEs but don't actually have all the MSRs */
965 if (c->x86 < 6)
966 clear_cpu_cap(c, X86_FEATURE_MCE);
967
968 switch (c->x86) {
969 case 4: init_amd_k5(c); break;
970 case 5: init_amd_k6(c); break;
971 case 6: init_amd_k7(c); break;
972 case 0xf: init_amd_k8(c); break;
973 case 0x10: init_amd_gh(c); break;
974 case 0x12: init_amd_ln(c); break;
975 case 0x15: init_amd_bd(c); break;
976 case 0x16: init_amd_jg(c); break;
977 }
978
979 /*
980 * Save up on some future enablement work and do common Zen
981 * settings.
982 */
983 if (c->x86 >= 0x17)
984 init_amd_zen_common();
985
986 if (boot_cpu_has(X86_FEATURE_ZEN1))
987 init_amd_zen1(c);
988 else if (boot_cpu_has(X86_FEATURE_ZEN2))
989 init_amd_zen2(c);
990 else if (boot_cpu_has(X86_FEATURE_ZEN3))
991 init_amd_zen3(c);
992 else if (boot_cpu_has(X86_FEATURE_ZEN4))
993 init_amd_zen4(c);
994 else if (boot_cpu_has(X86_FEATURE_ZEN5))
995 init_amd_zen5(c);
996
997 /*
998 * Enable workaround for FXSAVE leak on CPUs
999 * without a XSaveErPtr feature
1000 */
1001 if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
1002 set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
1003
1004 cpu_detect_cache_sizes(c);
1005
1006 srat_detect_node(c);
1007
1008 init_amd_cacheinfo(c);
1009
1010 if (cpu_has(c, X86_FEATURE_SVM)) {
1011 rdmsrl(MSR_VM_CR, vm_cr);
1012 if (vm_cr & SVM_VM_CR_SVM_DIS_MASK) {
1013 pr_notice_once("SVM disabled (by BIOS) in MSR_VM_CR\n");
1014 clear_cpu_cap(c, X86_FEATURE_SVM);
1015 }
1016 }
1017
1018 if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) {
1019 /*
1020 * Use LFENCE for execution serialization. On families which
1021 * don't have that MSR, LFENCE is already serializing.
1022 * msr_set_bit() uses the safe accessors, too, even if the MSR
1023 * is not present.
1024 */
1025 msr_set_bit(MSR_AMD64_DE_CFG,
1026 MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
1027
1028 /* A serializing LFENCE stops RDTSC speculation */
1029 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
1030 }
1031
1032 /*
1033 * Family 0x12 and above processors have APIC timer
1034 * running in deep C states.
1035 */
1036 if (c->x86 > 0x11)
1037 set_cpu_cap(c, X86_FEATURE_ARAT);
1038
1039 /* 3DNow or LM implies PREFETCHW */
1040 if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
1041 if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
1042 set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
1043
1044 /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
1045 if (!cpu_feature_enabled(X86_FEATURE_XENPV))
1046 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
1047
1048 /*
1049 * Turn on the Instructions Retired free counter on machines not
1050 * susceptible to erratum #1054 "Instructions Retired Performance
1051 * Counter May Be Inaccurate".
1052 */
1053 if (cpu_has(c, X86_FEATURE_IRPERF) &&
1054 (boot_cpu_has(X86_FEATURE_ZEN1) && c->x86_model > 0x2f))
1055 msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
1056
1057 check_null_seg_clears_base(c);
1058
1059 /*
1060 * Make sure EFER[AIBRSE - Automatic IBRS Enable] is set. The APs are brought up
1061 * using the trampoline code and as part of it, MSR_EFER gets prepared there in
1062 * order to be replicated onto them. Regardless, set it here again, if not set,
1063 * to protect against any future refactoring/code reorganization which might
1064 * miss setting this important bit.
1065 */
1066 if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
1067 cpu_has(c, X86_FEATURE_AUTOIBRS))
1068 WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS) < 0);
1069
1070 /* AMD CPUs don't need fencing after x2APIC/TSC_DEADLINE MSR writes. */
1071 clear_cpu_cap(c, X86_FEATURE_APIC_MSRS_FENCE);
1072}
1073
1074#ifdef CONFIG_X86_32
1075static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
1076{
1077 /* AMD errata T13 (order #21922) */
1078 if (c->x86 == 6) {
1079 /* Duron Rev A0 */
1080 if (c->x86_model == 3 && c->x86_stepping == 0)
1081 size = 64;
1082 /* Tbird rev A1/A2 */
1083 if (c->x86_model == 4 &&
1084 (c->x86_stepping == 0 || c->x86_stepping == 1))
1085 size = 256;
1086 }
1087 return size;
1088}
1089#endif
1090
1091static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1092{
1093 u32 ebx, eax, ecx, edx;
1094 u16 mask = 0xfff;
1095
1096 if (c->x86 < 0xf)
1097 return;
1098
1099 if (c->extended_cpuid_level < 0x80000006)
1100 return;
1101
1102 cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1103
1104 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1105 tlb_lli_4k[ENTRIES] = ebx & mask;
1106
1107 /*
1108 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1109 * characteristics from the CPUID function 0x80000005 instead.
1110 */
1111 if (c->x86 == 0xf) {
1112 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1113 mask = 0xff;
1114 }
1115
1116 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1117 if (!((eax >> 16) & mask))
1118 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1119 else
1120 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1121
1122 /* a 4M entry uses two 2M entries */
1123 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1124
1125 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1126 if (!(eax & mask)) {
1127 /* Erratum 658 */
1128 if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1129 tlb_lli_2m[ENTRIES] = 1024;
1130 } else {
1131 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1132 tlb_lli_2m[ENTRIES] = eax & 0xff;
1133 }
1134 } else
1135 tlb_lli_2m[ENTRIES] = eax & mask;
1136
1137 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1138}
1139
1140static const struct cpu_dev amd_cpu_dev = {
1141 .c_vendor = "AMD",
1142 .c_ident = { "AuthenticAMD" },
1143#ifdef CONFIG_X86_32
1144 .legacy_models = {
1145 { .family = 4, .model_names =
1146 {
1147 [3] = "486 DX/2",
1148 [7] = "486 DX/2-WB",
1149 [8] = "486 DX/4",
1150 [9] = "486 DX/4-WB",
1151 [14] = "Am5x86-WT",
1152 [15] = "Am5x86-WB"
1153 }
1154 },
1155 },
1156 .legacy_cache_size = amd_size_cache,
1157#endif
1158 .c_early_init = early_init_amd,
1159 .c_detect_tlb = cpu_detect_tlb_amd,
1160 .c_bsp_init = bsp_init_amd,
1161 .c_init = init_amd,
1162 .c_x86_vendor = X86_VENDOR_AMD,
1163};
1164
1165cpu_dev_register(amd_cpu_dev);
1166
1167static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[4], amd_dr_addr_mask);
1168
1169static unsigned int amd_msr_dr_addr_masks[] = {
1170 MSR_F16H_DR0_ADDR_MASK,
1171 MSR_F16H_DR1_ADDR_MASK,
1172 MSR_F16H_DR1_ADDR_MASK + 1,
1173 MSR_F16H_DR1_ADDR_MASK + 2
1174};
1175
1176void amd_set_dr_addr_mask(unsigned long mask, unsigned int dr)
1177{
1178 int cpu = smp_processor_id();
1179
1180 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1181 return;
1182
1183 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1184 return;
1185
1186 if (per_cpu(amd_dr_addr_mask, cpu)[dr] == mask)
1187 return;
1188
1189 wrmsr(amd_msr_dr_addr_masks[dr], mask, 0);
1190 per_cpu(amd_dr_addr_mask, cpu)[dr] = mask;
1191}
1192
1193unsigned long amd_get_dr_addr_mask(unsigned int dr)
1194{
1195 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1196 return 0;
1197
1198 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1199 return 0;
1200
1201 return per_cpu(amd_dr_addr_mask[dr], smp_processor_id());
1202}
1203EXPORT_SYMBOL_GPL(amd_get_dr_addr_mask);
1204
1205static void zenbleed_check_cpu(void *unused)
1206{
1207 struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
1208
1209 zen2_zenbleed_check(c);
1210}
1211
1212void amd_check_microcode(void)
1213{
1214 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
1215 return;
1216
1217 if (cpu_feature_enabled(X86_FEATURE_ZEN2))
1218 on_each_cpu(zenbleed_check_cpu, NULL, 1);
1219}