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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/pci-direct.h>
19#include <asm/delay.h>
20#include <asm/debugreg.h>
21
22#ifdef CONFIG_X86_64
23# include <asm/mmconfig.h>
24# include <asm/set_memory.h>
25#endif
26
27#include "cpu.h"
28
29static const int amd_erratum_383[];
30static const int amd_erratum_400[];
31static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
32
33/*
34 * nodes_per_socket: Stores the number of nodes per socket.
35 * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
36 * Node Identifiers[10:8]
37 */
38static u32 nodes_per_socket = 1;
39
40static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
41{
42 u32 gprs[8] = { 0 };
43 int err;
44
45 WARN_ONCE((boot_cpu_data.x86 != 0xf),
46 "%s should only be used on K8!\n", __func__);
47
48 gprs[1] = msr;
49 gprs[7] = 0x9c5a203a;
50
51 err = rdmsr_safe_regs(gprs);
52
53 *p = gprs[0] | ((u64)gprs[2] << 32);
54
55 return err;
56}
57
58static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
59{
60 u32 gprs[8] = { 0 };
61
62 WARN_ONCE((boot_cpu_data.x86 != 0xf),
63 "%s should only be used on K8!\n", __func__);
64
65 gprs[0] = (u32)val;
66 gprs[1] = msr;
67 gprs[2] = val >> 32;
68 gprs[7] = 0x9c5a203a;
69
70 return wrmsr_safe_regs(gprs);
71}
72
73/*
74 * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
75 * misexecution of code under Linux. Owners of such processors should
76 * contact AMD for precise details and a CPU swap.
77 *
78 * See http://www.multimania.com/poulot/k6bug.html
79 * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
80 * (Publication # 21266 Issue Date: August 1998)
81 *
82 * The following test is erm.. interesting. AMD neglected to up
83 * the chip setting when fixing the bug but they also tweaked some
84 * performance at the same time..
85 */
86
87#ifdef CONFIG_X86_32
88extern __visible void vide(void);
89__asm__(".text\n"
90 ".globl vide\n"
91 ".type vide, @function\n"
92 ".align 4\n"
93 "vide: ret\n");
94#endif
95
96static void init_amd_k5(struct cpuinfo_x86 *c)
97{
98#ifdef CONFIG_X86_32
99/*
100 * General Systems BIOSen alias the cpu frequency registers
101 * of the Elan at 0x000df000. Unfortunately, one of the Linux
102 * drivers subsequently pokes it, and changes the CPU speed.
103 * Workaround : Remove the unneeded alias.
104 */
105#define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
106#define CBAR_ENB (0x80000000)
107#define CBAR_KEY (0X000000CB)
108 if (c->x86_model == 9 || c->x86_model == 10) {
109 if (inl(CBAR) & CBAR_ENB)
110 outl(0 | CBAR_KEY, CBAR);
111 }
112#endif
113}
114
115static void init_amd_k6(struct cpuinfo_x86 *c)
116{
117#ifdef CONFIG_X86_32
118 u32 l, h;
119 int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
120
121 if (c->x86_model < 6) {
122 /* Based on AMD doc 20734R - June 2000 */
123 if (c->x86_model == 0) {
124 clear_cpu_cap(c, X86_FEATURE_APIC);
125 set_cpu_cap(c, X86_FEATURE_PGE);
126 }
127 return;
128 }
129
130 if (c->x86_model == 6 && c->x86_stepping == 1) {
131 const int K6_BUG_LOOP = 1000000;
132 int n;
133 void (*f_vide)(void);
134 u64 d, d2;
135
136 pr_info("AMD K6 stepping B detected - ");
137
138 /*
139 * It looks like AMD fixed the 2.6.2 bug and improved indirect
140 * calls at the same time.
141 */
142
143 n = K6_BUG_LOOP;
144 f_vide = vide;
145 OPTIMIZER_HIDE_VAR(f_vide);
146 d = rdtsc();
147 while (n--)
148 f_vide();
149 d2 = rdtsc();
150 d = d2-d;
151
152 if (d > 20*K6_BUG_LOOP)
153 pr_cont("system stability may be impaired when more than 32 MB are used.\n");
154 else
155 pr_cont("probably OK (after B9730xxxx).\n");
156 }
157
158 /* K6 with old style WHCR */
159 if (c->x86_model < 8 ||
160 (c->x86_model == 8 && c->x86_stepping < 8)) {
161 /* We can only write allocate on the low 508Mb */
162 if (mbytes > 508)
163 mbytes = 508;
164
165 rdmsr(MSR_K6_WHCR, l, h);
166 if ((l&0x0000FFFF) == 0) {
167 unsigned long flags;
168 l = (1<<0)|((mbytes/4)<<1);
169 local_irq_save(flags);
170 wbinvd();
171 wrmsr(MSR_K6_WHCR, l, h);
172 local_irq_restore(flags);
173 pr_info("Enabling old style K6 write allocation for %d Mb\n",
174 mbytes);
175 }
176 return;
177 }
178
179 if ((c->x86_model == 8 && c->x86_stepping > 7) ||
180 c->x86_model == 9 || c->x86_model == 13) {
181 /* The more serious chips .. */
182
183 if (mbytes > 4092)
184 mbytes = 4092;
185
186 rdmsr(MSR_K6_WHCR, l, h);
187 if ((l&0xFFFF0000) == 0) {
188 unsigned long flags;
189 l = ((mbytes>>2)<<22)|(1<<16);
190 local_irq_save(flags);
191 wbinvd();
192 wrmsr(MSR_K6_WHCR, l, h);
193 local_irq_restore(flags);
194 pr_info("Enabling new style K6 write allocation for %d Mb\n",
195 mbytes);
196 }
197
198 return;
199 }
200
201 if (c->x86_model == 10) {
202 /* AMD Geode LX is model 10 */
203 /* placeholder for any needed mods */
204 return;
205 }
206#endif
207}
208
209static void init_amd_k7(struct cpuinfo_x86 *c)
210{
211#ifdef CONFIG_X86_32
212 u32 l, h;
213
214 /*
215 * Bit 15 of Athlon specific MSR 15, needs to be 0
216 * to enable SSE on Palomino/Morgan/Barton CPU's.
217 * If the BIOS didn't enable it already, enable it here.
218 */
219 if (c->x86_model >= 6 && c->x86_model <= 10) {
220 if (!cpu_has(c, X86_FEATURE_XMM)) {
221 pr_info("Enabling disabled K7/SSE Support.\n");
222 msr_clear_bit(MSR_K7_HWCR, 15);
223 set_cpu_cap(c, X86_FEATURE_XMM);
224 }
225 }
226
227 /*
228 * It's been determined by AMD that Athlons since model 8 stepping 1
229 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
230 * As per AMD technical note 27212 0.2
231 */
232 if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
233 rdmsr(MSR_K7_CLK_CTL, l, h);
234 if ((l & 0xfff00000) != 0x20000000) {
235 pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
236 l, ((l & 0x000fffff)|0x20000000));
237 wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
238 }
239 }
240
241 /* calling is from identify_secondary_cpu() ? */
242 if (!c->cpu_index)
243 return;
244
245 /*
246 * Certain Athlons might work (for various values of 'work') in SMP
247 * but they are not certified as MP capable.
248 */
249 /* Athlon 660/661 is valid. */
250 if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
251 (c->x86_stepping == 1)))
252 return;
253
254 /* Duron 670 is valid */
255 if ((c->x86_model == 7) && (c->x86_stepping == 0))
256 return;
257
258 /*
259 * Athlon 662, Duron 671, and Athlon >model 7 have capability
260 * bit. It's worth noting that the A5 stepping (662) of some
261 * Athlon XP's have the MP bit set.
262 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
263 * more.
264 */
265 if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
266 ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
267 (c->x86_model > 7))
268 if (cpu_has(c, X86_FEATURE_MP))
269 return;
270
271 /* If we get here, not a certified SMP capable AMD system. */
272
273 /*
274 * Don't taint if we are running SMP kernel on a single non-MP
275 * approved Athlon
276 */
277 WARN_ONCE(1, "WARNING: This combination of AMD"
278 " processors is not suitable for SMP.\n");
279 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
280#endif
281}
282
283#ifdef CONFIG_NUMA
284/*
285 * To workaround broken NUMA config. Read the comment in
286 * srat_detect_node().
287 */
288static int nearby_node(int apicid)
289{
290 int i, node;
291
292 for (i = apicid - 1; i >= 0; i--) {
293 node = __apicid_to_node[i];
294 if (node != NUMA_NO_NODE && node_online(node))
295 return node;
296 }
297 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
298 node = __apicid_to_node[i];
299 if (node != NUMA_NO_NODE && node_online(node))
300 return node;
301 }
302 return first_node(node_online_map); /* Shouldn't happen */
303}
304#endif
305
306/*
307 * Fix up cpu_core_id for pre-F17h systems to be in the
308 * [0 .. cores_per_node - 1] range. Not really needed but
309 * kept so as not to break existing setups.
310 */
311static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
312{
313 u32 cus_per_node;
314
315 if (c->x86 >= 0x17)
316 return;
317
318 cus_per_node = c->x86_max_cores / nodes_per_socket;
319 c->cpu_core_id %= cus_per_node;
320}
321
322
323static void amd_get_topology_early(struct cpuinfo_x86 *c)
324{
325 if (cpu_has(c, X86_FEATURE_TOPOEXT))
326 smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
327}
328
329/*
330 * Fixup core topology information for
331 * (1) AMD multi-node processors
332 * Assumption: Number of cores in each internal node is the same.
333 * (2) AMD processors supporting compute units
334 */
335static void amd_get_topology(struct cpuinfo_x86 *c)
336{
337 u8 node_id;
338 int cpu = smp_processor_id();
339
340 /* get information required for multi-node processors */
341 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
342 int err;
343 u32 eax, ebx, ecx, edx;
344
345 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
346
347 node_id = ecx & 0xff;
348
349 if (c->x86 == 0x15)
350 c->cu_id = ebx & 0xff;
351
352 if (c->x86 >= 0x17) {
353 c->cpu_core_id = ebx & 0xff;
354
355 if (smp_num_siblings > 1)
356 c->x86_max_cores /= smp_num_siblings;
357 }
358
359 /*
360 * In case leaf B is available, use it to derive
361 * topology information.
362 */
363 err = detect_extended_topology(c);
364 if (!err)
365 c->x86_coreid_bits = get_count_order(c->x86_max_cores);
366
367 cacheinfo_amd_init_llc_id(c, cpu, node_id);
368
369 } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
370 u64 value;
371
372 rdmsrl(MSR_FAM10H_NODE_ID, value);
373 node_id = value & 7;
374
375 per_cpu(cpu_llc_id, cpu) = node_id;
376 } else
377 return;
378
379 if (nodes_per_socket > 1) {
380 set_cpu_cap(c, X86_FEATURE_AMD_DCM);
381 legacy_fixup_core_id(c);
382 }
383}
384
385/*
386 * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
387 * Assumes number of cores is a power of two.
388 */
389static void amd_detect_cmp(struct cpuinfo_x86 *c)
390{
391 unsigned bits;
392 int cpu = smp_processor_id();
393
394 bits = c->x86_coreid_bits;
395 /* Low order bits define the core id (index of core in socket) */
396 c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
397 /* Convert the initial APIC ID into the socket ID */
398 c->phys_proc_id = c->initial_apicid >> bits;
399 /* use socket ID also for last level cache */
400 per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
401}
402
403u16 amd_get_nb_id(int cpu)
404{
405 return per_cpu(cpu_llc_id, cpu);
406}
407EXPORT_SYMBOL_GPL(amd_get_nb_id);
408
409u32 amd_get_nodes_per_socket(void)
410{
411 return nodes_per_socket;
412}
413EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
414
415static void srat_detect_node(struct cpuinfo_x86 *c)
416{
417#ifdef CONFIG_NUMA
418 int cpu = smp_processor_id();
419 int node;
420 unsigned apicid = c->apicid;
421
422 node = numa_cpu_node(cpu);
423 if (node == NUMA_NO_NODE)
424 node = per_cpu(cpu_llc_id, cpu);
425
426 /*
427 * On multi-fabric platform (e.g. Numascale NumaChip) a
428 * platform-specific handler needs to be called to fixup some
429 * IDs of the CPU.
430 */
431 if (x86_cpuinit.fixup_cpu_id)
432 x86_cpuinit.fixup_cpu_id(c, node);
433
434 if (!node_online(node)) {
435 /*
436 * Two possibilities here:
437 *
438 * - The CPU is missing memory and no node was created. In
439 * that case try picking one from a nearby CPU.
440 *
441 * - The APIC IDs differ from the HyperTransport node IDs
442 * which the K8 northbridge parsing fills in. Assume
443 * they are all increased by a constant offset, but in
444 * the same order as the HT nodeids. If that doesn't
445 * result in a usable node fall back to the path for the
446 * previous case.
447 *
448 * This workaround operates directly on the mapping between
449 * APIC ID and NUMA node, assuming certain relationship
450 * between APIC ID, HT node ID and NUMA topology. As going
451 * through CPU mapping may alter the outcome, directly
452 * access __apicid_to_node[].
453 */
454 int ht_nodeid = c->initial_apicid;
455
456 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
457 node = __apicid_to_node[ht_nodeid];
458 /* Pick a nearby node */
459 if (!node_online(node))
460 node = nearby_node(apicid);
461 }
462 numa_set_node(cpu, node);
463#endif
464}
465
466static void early_init_amd_mc(struct cpuinfo_x86 *c)
467{
468#ifdef CONFIG_SMP
469 unsigned bits, ecx;
470
471 /* Multi core CPU? */
472 if (c->extended_cpuid_level < 0x80000008)
473 return;
474
475 ecx = cpuid_ecx(0x80000008);
476
477 c->x86_max_cores = (ecx & 0xff) + 1;
478
479 /* CPU telling us the core id bits shift? */
480 bits = (ecx >> 12) & 0xF;
481
482 /* Otherwise recompute */
483 if (bits == 0) {
484 while ((1 << bits) < c->x86_max_cores)
485 bits++;
486 }
487
488 c->x86_coreid_bits = bits;
489#endif
490}
491
492static void bsp_init_amd(struct cpuinfo_x86 *c)
493{
494
495#ifdef CONFIG_X86_64
496 if (c->x86 >= 0xf) {
497 unsigned long long tseg;
498
499 /*
500 * Split up direct mapping around the TSEG SMM area.
501 * Don't do it for gbpages because there seems very little
502 * benefit in doing so.
503 */
504 if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
505 unsigned long pfn = tseg >> PAGE_SHIFT;
506
507 pr_debug("tseg: %010llx\n", tseg);
508 if (pfn_range_is_mapped(pfn, pfn + 1))
509 set_memory_4k((unsigned long)__va(tseg), 1);
510 }
511 }
512#endif
513
514 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
515
516 if (c->x86 > 0x10 ||
517 (c->x86 == 0x10 && c->x86_model >= 0x2)) {
518 u64 val;
519
520 rdmsrl(MSR_K7_HWCR, val);
521 if (!(val & BIT(24)))
522 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
523 }
524 }
525
526 if (c->x86 == 0x15) {
527 unsigned long upperbit;
528 u32 cpuid, assoc;
529
530 cpuid = cpuid_edx(0x80000005);
531 assoc = cpuid >> 16 & 0xff;
532 upperbit = ((cpuid >> 24) << 10) / assoc;
533
534 va_align.mask = (upperbit - 1) & PAGE_MASK;
535 va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
536
537 /* A random value per boot for bit slice [12:upper_bit) */
538 va_align.bits = get_random_int() & va_align.mask;
539 }
540
541 if (cpu_has(c, X86_FEATURE_MWAITX))
542 use_mwaitx_delay();
543
544 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
545 u32 ecx;
546
547 ecx = cpuid_ecx(0x8000001e);
548 nodes_per_socket = ((ecx >> 8) & 7) + 1;
549 } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
550 u64 value;
551
552 rdmsrl(MSR_FAM10H_NODE_ID, value);
553 nodes_per_socket = ((value >> 3) & 7) + 1;
554 }
555
556 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
557 !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
558 c->x86 >= 0x15 && c->x86 <= 0x17) {
559 unsigned int bit;
560
561 switch (c->x86) {
562 case 0x15: bit = 54; break;
563 case 0x16: bit = 33; break;
564 case 0x17: bit = 10; break;
565 default: return;
566 }
567 /*
568 * Try to cache the base value so further operations can
569 * avoid RMW. If that faults, do not enable SSBD.
570 */
571 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
572 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
573 setup_force_cpu_cap(X86_FEATURE_SSBD);
574 x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
575 }
576 }
577}
578
579static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
580{
581 u64 msr;
582
583 /*
584 * BIOS support is required for SME and SEV.
585 * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
586 * the SME physical address space reduction value.
587 * If BIOS has not enabled SME then don't advertise the
588 * SME feature (set in scattered.c).
589 * For SEV: If BIOS has not enabled SEV then don't advertise the
590 * SEV feature (set in scattered.c).
591 *
592 * In all cases, since support for SME and SEV requires long mode,
593 * don't advertise the feature under CONFIG_X86_32.
594 */
595 if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
596 /* Check if memory encryption is enabled */
597 rdmsrl(MSR_K8_SYSCFG, msr);
598 if (!(msr & MSR_K8_SYSCFG_MEM_ENCRYPT))
599 goto clear_all;
600
601 /*
602 * Always adjust physical address bits. Even though this
603 * will be a value above 32-bits this is still done for
604 * CONFIG_X86_32 so that accurate values are reported.
605 */
606 c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
607
608 if (IS_ENABLED(CONFIG_X86_32))
609 goto clear_all;
610
611 rdmsrl(MSR_K7_HWCR, msr);
612 if (!(msr & MSR_K7_HWCR_SMMLOCK))
613 goto clear_sev;
614
615 return;
616
617clear_all:
618 clear_cpu_cap(c, X86_FEATURE_SME);
619clear_sev:
620 clear_cpu_cap(c, X86_FEATURE_SEV);
621 }
622}
623
624static void early_init_amd(struct cpuinfo_x86 *c)
625{
626 u64 value;
627 u32 dummy;
628
629 early_init_amd_mc(c);
630
631#ifdef CONFIG_X86_32
632 if (c->x86 == 6)
633 set_cpu_cap(c, X86_FEATURE_K7);
634#endif
635
636 if (c->x86 >= 0xf)
637 set_cpu_cap(c, X86_FEATURE_K8);
638
639 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
640
641 /*
642 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
643 * with P/T states and does not stop in deep C-states
644 */
645 if (c->x86_power & (1 << 8)) {
646 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
647 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
648 }
649
650 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
651 if (c->x86_power & BIT(12))
652 set_cpu_cap(c, X86_FEATURE_ACC_POWER);
653
654#ifdef CONFIG_X86_64
655 set_cpu_cap(c, X86_FEATURE_SYSCALL32);
656#else
657 /* Set MTRR capability flag if appropriate */
658 if (c->x86 == 5)
659 if (c->x86_model == 13 || c->x86_model == 9 ||
660 (c->x86_model == 8 && c->x86_stepping >= 8))
661 set_cpu_cap(c, X86_FEATURE_K6_MTRR);
662#endif
663#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
664 /*
665 * ApicID can always be treated as an 8-bit value for AMD APIC versions
666 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
667 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
668 * after 16h.
669 */
670 if (boot_cpu_has(X86_FEATURE_APIC)) {
671 if (c->x86 > 0x16)
672 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
673 else if (c->x86 >= 0xf) {
674 /* check CPU config space for extended APIC ID */
675 unsigned int val;
676
677 val = read_pci_config(0, 24, 0, 0x68);
678 if ((val >> 17 & 0x3) == 0x3)
679 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
680 }
681 }
682#endif
683
684 /*
685 * This is only needed to tell the kernel whether to use VMCALL
686 * and VMMCALL. VMMCALL is never executed except under virt, so
687 * we can set it unconditionally.
688 */
689 set_cpu_cap(c, X86_FEATURE_VMMCALL);
690
691 /* F16h erratum 793, CVE-2013-6885 */
692 if (c->x86 == 0x16 && c->x86_model <= 0xf)
693 msr_set_bit(MSR_AMD64_LS_CFG, 15);
694
695 /*
696 * Check whether the machine is affected by erratum 400. This is
697 * used to select the proper idle routine and to enable the check
698 * whether the machine is affected in arch_post_acpi_init(), which
699 * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
700 */
701 if (cpu_has_amd_erratum(c, amd_erratum_400))
702 set_cpu_bug(c, X86_BUG_AMD_E400);
703
704 early_detect_mem_encrypt(c);
705
706 /* Re-enable TopologyExtensions if switched off by BIOS */
707 if (c->x86 == 0x15 &&
708 (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
709 !cpu_has(c, X86_FEATURE_TOPOEXT)) {
710
711 if (msr_set_bit(0xc0011005, 54) > 0) {
712 rdmsrl(0xc0011005, value);
713 if (value & BIT_64(54)) {
714 set_cpu_cap(c, X86_FEATURE_TOPOEXT);
715 pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
716 }
717 }
718 }
719
720 amd_get_topology_early(c);
721}
722
723static void init_amd_k8(struct cpuinfo_x86 *c)
724{
725 u32 level;
726 u64 value;
727
728 /* On C+ stepping K8 rep microcode works well for copy/memset */
729 level = cpuid_eax(1);
730 if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
731 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
732
733 /*
734 * Some BIOSes incorrectly force this feature, but only K8 revision D
735 * (model = 0x14) and later actually support it.
736 * (AMD Erratum #110, docId: 25759).
737 */
738 if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
739 clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
740 if (!rdmsrl_amd_safe(0xc001100d, &value)) {
741 value &= ~BIT_64(32);
742 wrmsrl_amd_safe(0xc001100d, value);
743 }
744 }
745
746 if (!c->x86_model_id[0])
747 strcpy(c->x86_model_id, "Hammer");
748
749#ifdef CONFIG_SMP
750 /*
751 * Disable TLB flush filter by setting HWCR.FFDIS on K8
752 * bit 6 of msr C001_0015
753 *
754 * Errata 63 for SH-B3 steppings
755 * Errata 122 for all steppings (F+ have it disabled by default)
756 */
757 msr_set_bit(MSR_K7_HWCR, 6);
758#endif
759 set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
760}
761
762static void init_amd_gh(struct cpuinfo_x86 *c)
763{
764#ifdef CONFIG_MMCONF_FAM10H
765 /* do this for boot cpu */
766 if (c == &boot_cpu_data)
767 check_enable_amd_mmconf_dmi();
768
769 fam10h_check_enable_mmcfg();
770#endif
771
772 /*
773 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
774 * is always needed when GART is enabled, even in a kernel which has no
775 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
776 * If it doesn't, we do it here as suggested by the BKDG.
777 *
778 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
779 */
780 msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
781
782 /*
783 * On family 10h BIOS may not have properly enabled WC+ support, causing
784 * it to be converted to CD memtype. This may result in performance
785 * degradation for certain nested-paging guests. Prevent this conversion
786 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
787 *
788 * NOTE: we want to use the _safe accessors so as not to #GP kvm
789 * guests on older kvm hosts.
790 */
791 msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
792
793 if (cpu_has_amd_erratum(c, amd_erratum_383))
794 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
795}
796
797#define MSR_AMD64_DE_CFG 0xC0011029
798
799static void init_amd_ln(struct cpuinfo_x86 *c)
800{
801 /*
802 * Apply erratum 665 fix unconditionally so machines without a BIOS
803 * fix work.
804 */
805 msr_set_bit(MSR_AMD64_DE_CFG, 31);
806}
807
808static bool rdrand_force;
809
810static int __init rdrand_cmdline(char *str)
811{
812 if (!str)
813 return -EINVAL;
814
815 if (!strcmp(str, "force"))
816 rdrand_force = true;
817 else
818 return -EINVAL;
819
820 return 0;
821}
822early_param("rdrand", rdrand_cmdline);
823
824static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
825{
826 /*
827 * Saving of the MSR used to hide the RDRAND support during
828 * suspend/resume is done by arch/x86/power/cpu.c, which is
829 * dependent on CONFIG_PM_SLEEP.
830 */
831 if (!IS_ENABLED(CONFIG_PM_SLEEP))
832 return;
833
834 /*
835 * The nordrand option can clear X86_FEATURE_RDRAND, so check for
836 * RDRAND support using the CPUID function directly.
837 */
838 if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
839 return;
840
841 msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
842
843 /*
844 * Verify that the CPUID change has occurred in case the kernel is
845 * running virtualized and the hypervisor doesn't support the MSR.
846 */
847 if (cpuid_ecx(1) & BIT(30)) {
848 pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
849 return;
850 }
851
852 clear_cpu_cap(c, X86_FEATURE_RDRAND);
853 pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
854}
855
856static void init_amd_jg(struct cpuinfo_x86 *c)
857{
858 /*
859 * Some BIOS implementations do not restore proper RDRAND support
860 * across suspend and resume. Check on whether to hide the RDRAND
861 * instruction support via CPUID.
862 */
863 clear_rdrand_cpuid_bit(c);
864}
865
866static void init_amd_bd(struct cpuinfo_x86 *c)
867{
868 u64 value;
869
870 /*
871 * The way access filter has a performance penalty on some workloads.
872 * Disable it on the affected CPUs.
873 */
874 if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
875 if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
876 value |= 0x1E;
877 wrmsrl_safe(MSR_F15H_IC_CFG, value);
878 }
879 }
880
881 /*
882 * Some BIOS implementations do not restore proper RDRAND support
883 * across suspend and resume. Check on whether to hide the RDRAND
884 * instruction support via CPUID.
885 */
886 clear_rdrand_cpuid_bit(c);
887}
888
889static void init_amd_zn(struct cpuinfo_x86 *c)
890{
891 set_cpu_cap(c, X86_FEATURE_ZEN);
892
893#ifdef CONFIG_NUMA
894 node_reclaim_distance = 32;
895#endif
896
897 /*
898 * Fix erratum 1076: CPB feature bit not being set in CPUID.
899 * Always set it, except when running under a hypervisor.
900 */
901 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_CPB))
902 set_cpu_cap(c, X86_FEATURE_CPB);
903}
904
905static void init_amd(struct cpuinfo_x86 *c)
906{
907 early_init_amd(c);
908
909 /*
910 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
911 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
912 */
913 clear_cpu_cap(c, 0*32+31);
914
915 if (c->x86 >= 0x10)
916 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
917
918 /* get apicid instead of initial apic id from cpuid */
919 c->apicid = hard_smp_processor_id();
920
921 /* K6s reports MCEs but don't actually have all the MSRs */
922 if (c->x86 < 6)
923 clear_cpu_cap(c, X86_FEATURE_MCE);
924
925 switch (c->x86) {
926 case 4: init_amd_k5(c); break;
927 case 5: init_amd_k6(c); break;
928 case 6: init_amd_k7(c); break;
929 case 0xf: init_amd_k8(c); break;
930 case 0x10: init_amd_gh(c); break;
931 case 0x12: init_amd_ln(c); break;
932 case 0x15: init_amd_bd(c); break;
933 case 0x16: init_amd_jg(c); break;
934 case 0x17: init_amd_zn(c); break;
935 }
936
937 /*
938 * Enable workaround for FXSAVE leak on CPUs
939 * without a XSaveErPtr feature
940 */
941 if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
942 set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
943
944 cpu_detect_cache_sizes(c);
945
946 amd_detect_cmp(c);
947 amd_get_topology(c);
948 srat_detect_node(c);
949
950 init_amd_cacheinfo(c);
951
952 if (cpu_has(c, X86_FEATURE_XMM2)) {
953 /*
954 * Use LFENCE for execution serialization. On families which
955 * don't have that MSR, LFENCE is already serializing.
956 * msr_set_bit() uses the safe accessors, too, even if the MSR
957 * is not present.
958 */
959 msr_set_bit(MSR_F10H_DECFG,
960 MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT);
961
962 /* A serializing LFENCE stops RDTSC speculation */
963 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
964 }
965
966 /*
967 * Family 0x12 and above processors have APIC timer
968 * running in deep C states.
969 */
970 if (c->x86 > 0x11)
971 set_cpu_cap(c, X86_FEATURE_ARAT);
972
973 /* 3DNow or LM implies PREFETCHW */
974 if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
975 if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
976 set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
977
978 /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
979 if (!cpu_has(c, X86_FEATURE_XENPV))
980 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
981}
982
983#ifdef CONFIG_X86_32
984static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
985{
986 /* AMD errata T13 (order #21922) */
987 if (c->x86 == 6) {
988 /* Duron Rev A0 */
989 if (c->x86_model == 3 && c->x86_stepping == 0)
990 size = 64;
991 /* Tbird rev A1/A2 */
992 if (c->x86_model == 4 &&
993 (c->x86_stepping == 0 || c->x86_stepping == 1))
994 size = 256;
995 }
996 return size;
997}
998#endif
999
1000static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1001{
1002 u32 ebx, eax, ecx, edx;
1003 u16 mask = 0xfff;
1004
1005 if (c->x86 < 0xf)
1006 return;
1007
1008 if (c->extended_cpuid_level < 0x80000006)
1009 return;
1010
1011 cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1012
1013 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1014 tlb_lli_4k[ENTRIES] = ebx & mask;
1015
1016 /*
1017 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1018 * characteristics from the CPUID function 0x80000005 instead.
1019 */
1020 if (c->x86 == 0xf) {
1021 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1022 mask = 0xff;
1023 }
1024
1025 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1026 if (!((eax >> 16) & mask))
1027 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1028 else
1029 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1030
1031 /* a 4M entry uses two 2M entries */
1032 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1033
1034 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1035 if (!(eax & mask)) {
1036 /* Erratum 658 */
1037 if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1038 tlb_lli_2m[ENTRIES] = 1024;
1039 } else {
1040 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1041 tlb_lli_2m[ENTRIES] = eax & 0xff;
1042 }
1043 } else
1044 tlb_lli_2m[ENTRIES] = eax & mask;
1045
1046 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1047}
1048
1049static const struct cpu_dev amd_cpu_dev = {
1050 .c_vendor = "AMD",
1051 .c_ident = { "AuthenticAMD" },
1052#ifdef CONFIG_X86_32
1053 .legacy_models = {
1054 { .family = 4, .model_names =
1055 {
1056 [3] = "486 DX/2",
1057 [7] = "486 DX/2-WB",
1058 [8] = "486 DX/4",
1059 [9] = "486 DX/4-WB",
1060 [14] = "Am5x86-WT",
1061 [15] = "Am5x86-WB"
1062 }
1063 },
1064 },
1065 .legacy_cache_size = amd_size_cache,
1066#endif
1067 .c_early_init = early_init_amd,
1068 .c_detect_tlb = cpu_detect_tlb_amd,
1069 .c_bsp_init = bsp_init_amd,
1070 .c_init = init_amd,
1071 .c_x86_vendor = X86_VENDOR_AMD,
1072};
1073
1074cpu_dev_register(amd_cpu_dev);
1075
1076/*
1077 * AMD errata checking
1078 *
1079 * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
1080 * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
1081 * have an OSVW id assigned, which it takes as first argument. Both take a
1082 * variable number of family-specific model-stepping ranges created by
1083 * AMD_MODEL_RANGE().
1084 *
1085 * Example:
1086 *
1087 * const int amd_erratum_319[] =
1088 * AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
1089 * AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
1090 * AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
1091 */
1092
1093#define AMD_LEGACY_ERRATUM(...) { -1, __VA_ARGS__, 0 }
1094#define AMD_OSVW_ERRATUM(osvw_id, ...) { osvw_id, __VA_ARGS__, 0 }
1095#define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
1096 ((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
1097#define AMD_MODEL_RANGE_FAMILY(range) (((range) >> 24) & 0xff)
1098#define AMD_MODEL_RANGE_START(range) (((range) >> 12) & 0xfff)
1099#define AMD_MODEL_RANGE_END(range) ((range) & 0xfff)
1100
1101static const int amd_erratum_400[] =
1102 AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
1103 AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
1104
1105static const int amd_erratum_383[] =
1106 AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
1107
1108
1109static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
1110{
1111 int osvw_id = *erratum++;
1112 u32 range;
1113 u32 ms;
1114
1115 if (osvw_id >= 0 && osvw_id < 65536 &&
1116 cpu_has(cpu, X86_FEATURE_OSVW)) {
1117 u64 osvw_len;
1118
1119 rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
1120 if (osvw_id < osvw_len) {
1121 u64 osvw_bits;
1122
1123 rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
1124 osvw_bits);
1125 return osvw_bits & (1ULL << (osvw_id & 0x3f));
1126 }
1127 }
1128
1129 /* OSVW unavailable or ID unknown, match family-model-stepping range */
1130 ms = (cpu->x86_model << 4) | cpu->x86_stepping;
1131 while ((range = *erratum++))
1132 if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
1133 (ms >= AMD_MODEL_RANGE_START(range)) &&
1134 (ms <= AMD_MODEL_RANGE_END(range)))
1135 return true;
1136
1137 return false;
1138}
1139
1140void set_dr_addr_mask(unsigned long mask, int dr)
1141{
1142 if (!boot_cpu_has(X86_FEATURE_BPEXT))
1143 return;
1144
1145 switch (dr) {
1146 case 0:
1147 wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
1148 break;
1149 case 1:
1150 case 2:
1151 case 3:
1152 wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
1153 break;
1154 default:
1155 break;
1156 }
1157}
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);