1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/export.h>
3 #include <linux/bitops.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>
14 #include <asm/cacheinfo.h>
16 #include <asm/spec-ctrl.h>
19 #include <asm/pci-direct.h>
20 #include <asm/delay.h>
21 #include <asm/debugreg.h>
22 #include <asm/resctrl.h>
25 # include <asm/mmconfig.h>
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]
35 static u32 nodes_per_socket = 1;
40 * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
41 * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
42 * have an OSVW id assigned, which it takes as first argument. Both take a
43 * variable number of family-specific model-stepping ranges created by
48 * const int amd_erratum_319[] =
49 * AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
50 * AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
51 * AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
54 #define AMD_LEGACY_ERRATUM(...) { -1, __VA_ARGS__, 0 }
55 #define AMD_OSVW_ERRATUM(osvw_id, ...) { osvw_id, __VA_ARGS__, 0 }
56 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
57 ((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
58 #define AMD_MODEL_RANGE_FAMILY(range) (((range) >> 24) & 0xff)
59 #define AMD_MODEL_RANGE_START(range) (((range) >> 12) & 0xfff)
60 #define AMD_MODEL_RANGE_END(range) ((range) & 0xfff)
62 static const int amd_erratum_400[] =
63 AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
64 AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
66 static const int amd_erratum_383[] =
67 AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
69 /* #1054: Instructions Retired Performance Counter May Be Inaccurate */
70 static const int amd_erratum_1054[] =
71 AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
73 static const int amd_zenbleed[] =
74 AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
75 AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
76 AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
77 AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
79 static const int amd_div0[] =
80 AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
81 AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
83 static const int amd_erratum_1485[] =
84 AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf),
85 AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf));
87 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
89 int osvw_id = *erratum++;
93 if (osvw_id >= 0 && osvw_id < 65536 &&
94 cpu_has(cpu, X86_FEATURE_OSVW)) {
97 rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
98 if (osvw_id < osvw_len) {
101 rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
103 return osvw_bits & (1ULL << (osvw_id & 0x3f));
107 /* OSVW unavailable or ID unknown, match family-model-stepping range */
108 ms = (cpu->x86_model << 4) | cpu->x86_stepping;
109 while ((range = *erratum++))
110 if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
111 (ms >= AMD_MODEL_RANGE_START(range)) &&
112 (ms <= AMD_MODEL_RANGE_END(range)))
118 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
123 WARN_ONCE((boot_cpu_data.x86 != 0xf),
124 "%s should only be used on K8!\n", __func__);
127 gprs[7] = 0x9c5a203a;
129 err = rdmsr_safe_regs(gprs);
131 *p = gprs[0] | ((u64)gprs[2] << 32);
136 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
140 WARN_ONCE((boot_cpu_data.x86 != 0xf),
141 "%s should only be used on K8!\n", __func__);
146 gprs[7] = 0x9c5a203a;
148 return wrmsr_safe_regs(gprs);
152 * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
153 * misexecution of code under Linux. Owners of such processors should
154 * contact AMD for precise details and a CPU swap.
156 * See http://www.multimania.com/poulot/k6bug.html
157 * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
158 * (Publication # 21266 Issue Date: August 1998)
160 * The following test is erm.. interesting. AMD neglected to up
161 * the chip setting when fixing the bug but they also tweaked some
162 * performance at the same time..
166 extern __visible void vide(void);
169 ".type vide, @function\n"
174 static void init_amd_k5(struct cpuinfo_x86 *c)
178 * General Systems BIOSen alias the cpu frequency registers
179 * of the Elan at 0x000df000. Unfortunately, one of the Linux
180 * drivers subsequently pokes it, and changes the CPU speed.
181 * Workaround : Remove the unneeded alias.
183 #define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
184 #define CBAR_ENB (0x80000000)
185 #define CBAR_KEY (0X000000CB)
186 if (c->x86_model == 9 || c->x86_model == 10) {
187 if (inl(CBAR) & CBAR_ENB)
188 outl(0 | CBAR_KEY, CBAR);
193 static void init_amd_k6(struct cpuinfo_x86 *c)
197 int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
199 if (c->x86_model < 6) {
200 /* Based on AMD doc 20734R - June 2000 */
201 if (c->x86_model == 0) {
202 clear_cpu_cap(c, X86_FEATURE_APIC);
203 set_cpu_cap(c, X86_FEATURE_PGE);
208 if (c->x86_model == 6 && c->x86_stepping == 1) {
209 const int K6_BUG_LOOP = 1000000;
211 void (*f_vide)(void);
214 pr_info("AMD K6 stepping B detected - ");
217 * It looks like AMD fixed the 2.6.2 bug and improved indirect
218 * calls at the same time.
223 OPTIMIZER_HIDE_VAR(f_vide);
230 if (d > 20*K6_BUG_LOOP)
231 pr_cont("system stability may be impaired when more than 32 MB are used.\n");
233 pr_cont("probably OK (after B9730xxxx).\n");
236 /* K6 with old style WHCR */
237 if (c->x86_model < 8 ||
238 (c->x86_model == 8 && c->x86_stepping < 8)) {
239 /* We can only write allocate on the low 508Mb */
243 rdmsr(MSR_K6_WHCR, l, h);
244 if ((l&0x0000FFFF) == 0) {
246 l = (1<<0)|((mbytes/4)<<1);
247 local_irq_save(flags);
249 wrmsr(MSR_K6_WHCR, l, h);
250 local_irq_restore(flags);
251 pr_info("Enabling old style K6 write allocation for %d Mb\n",
257 if ((c->x86_model == 8 && c->x86_stepping > 7) ||
258 c->x86_model == 9 || c->x86_model == 13) {
259 /* The more serious chips .. */
264 rdmsr(MSR_K6_WHCR, l, h);
265 if ((l&0xFFFF0000) == 0) {
267 l = ((mbytes>>2)<<22)|(1<<16);
268 local_irq_save(flags);
270 wrmsr(MSR_K6_WHCR, l, h);
271 local_irq_restore(flags);
272 pr_info("Enabling new style K6 write allocation for %d Mb\n",
279 if (c->x86_model == 10) {
280 /* AMD Geode LX is model 10 */
281 /* placeholder for any needed mods */
287 static void init_amd_k7(struct cpuinfo_x86 *c)
293 * Bit 15 of Athlon specific MSR 15, needs to be 0
294 * to enable SSE on Palomino/Morgan/Barton CPU's.
295 * If the BIOS didn't enable it already, enable it here.
297 if (c->x86_model >= 6 && c->x86_model <= 10) {
298 if (!cpu_has(c, X86_FEATURE_XMM)) {
299 pr_info("Enabling disabled K7/SSE Support.\n");
300 msr_clear_bit(MSR_K7_HWCR, 15);
301 set_cpu_cap(c, X86_FEATURE_XMM);
306 * It's been determined by AMD that Athlons since model 8 stepping 1
307 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
308 * As per AMD technical note 27212 0.2
310 if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
311 rdmsr(MSR_K7_CLK_CTL, l, h);
312 if ((l & 0xfff00000) != 0x20000000) {
313 pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
314 l, ((l & 0x000fffff)|0x20000000));
315 wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
319 /* calling is from identify_secondary_cpu() ? */
324 * Certain Athlons might work (for various values of 'work') in SMP
325 * but they are not certified as MP capable.
327 /* Athlon 660/661 is valid. */
328 if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
329 (c->x86_stepping == 1)))
332 /* Duron 670 is valid */
333 if ((c->x86_model == 7) && (c->x86_stepping == 0))
337 * Athlon 662, Duron 671, and Athlon >model 7 have capability
338 * bit. It's worth noting that the A5 stepping (662) of some
339 * Athlon XP's have the MP bit set.
340 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
343 if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
344 ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
346 if (cpu_has(c, X86_FEATURE_MP))
349 /* If we get here, not a certified SMP capable AMD system. */
352 * Don't taint if we are running SMP kernel on a single non-MP
355 WARN_ONCE(1, "WARNING: This combination of AMD"
356 " processors is not suitable for SMP.\n");
357 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
363 * To workaround broken NUMA config. Read the comment in
364 * srat_detect_node().
366 static int nearby_node(int apicid)
370 for (i = apicid - 1; i >= 0; i--) {
371 node = __apicid_to_node[i];
372 if (node != NUMA_NO_NODE && node_online(node))
375 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
376 node = __apicid_to_node[i];
377 if (node != NUMA_NO_NODE && node_online(node))
380 return first_node(node_online_map); /* Shouldn't happen */
385 * Fix up cpu_core_id for pre-F17h systems to be in the
386 * [0 .. cores_per_node - 1] range. Not really needed but
387 * kept so as not to break existing setups.
389 static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
396 cus_per_node = c->x86_max_cores / nodes_per_socket;
397 c->cpu_core_id %= cus_per_node;
401 * Fixup core topology information for
402 * (1) AMD multi-node processors
403 * Assumption: Number of cores in each internal node is the same.
404 * (2) AMD processors supporting compute units
406 static void amd_get_topology(struct cpuinfo_x86 *c)
408 int cpu = smp_processor_id();
410 /* get information required for multi-node processors */
411 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
413 u32 eax, ebx, ecx, edx;
415 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
417 c->cpu_die_id = ecx & 0xff;
420 c->cu_id = ebx & 0xff;
422 if (c->x86 >= 0x17) {
423 c->cpu_core_id = ebx & 0xff;
425 if (smp_num_siblings > 1)
426 c->x86_max_cores /= smp_num_siblings;
430 * In case leaf B is available, use it to derive
431 * topology information.
433 err = detect_extended_topology(c);
435 c->x86_coreid_bits = get_count_order(c->x86_max_cores);
437 cacheinfo_amd_init_llc_id(c, cpu);
439 } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
442 rdmsrl(MSR_FAM10H_NODE_ID, value);
443 c->cpu_die_id = value & 7;
445 per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
449 if (nodes_per_socket > 1) {
450 set_cpu_cap(c, X86_FEATURE_AMD_DCM);
451 legacy_fixup_core_id(c);
456 * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
457 * Assumes number of cores is a power of two.
459 static void amd_detect_cmp(struct cpuinfo_x86 *c)
462 int cpu = smp_processor_id();
464 bits = c->x86_coreid_bits;
465 /* Low order bits define the core id (index of core in socket) */
466 c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
467 /* Convert the initial APIC ID into the socket ID */
468 c->phys_proc_id = c->initial_apicid >> bits;
469 /* use socket ID also for last level cache */
470 per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
473 static void amd_detect_ppin(struct cpuinfo_x86 *c)
475 unsigned long long val;
477 if (!cpu_has(c, X86_FEATURE_AMD_PPIN))
480 /* When PPIN is defined in CPUID, still need to check PPIN_CTL MSR */
481 if (rdmsrl_safe(MSR_AMD_PPIN_CTL, &val))
484 /* PPIN is locked in disabled mode, clear feature bit */
485 if ((val & 3UL) == 1UL)
488 /* If PPIN is disabled, try to enable it */
490 wrmsrl_safe(MSR_AMD_PPIN_CTL, val | 2UL);
491 rdmsrl_safe(MSR_AMD_PPIN_CTL, &val);
494 /* If PPIN_EN bit is 1, return from here; otherwise fall through */
499 clear_cpu_cap(c, X86_FEATURE_AMD_PPIN);
502 u32 amd_get_nodes_per_socket(void)
504 return nodes_per_socket;
506 EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
508 static void srat_detect_node(struct cpuinfo_x86 *c)
511 int cpu = smp_processor_id();
513 unsigned apicid = c->apicid;
515 node = numa_cpu_node(cpu);
516 if (node == NUMA_NO_NODE)
517 node = get_llc_id(cpu);
520 * On multi-fabric platform (e.g. Numascale NumaChip) a
521 * platform-specific handler needs to be called to fixup some
524 if (x86_cpuinit.fixup_cpu_id)
525 x86_cpuinit.fixup_cpu_id(c, node);
527 if (!node_online(node)) {
529 * Two possibilities here:
531 * - The CPU is missing memory and no node was created. In
532 * that case try picking one from a nearby CPU.
534 * - The APIC IDs differ from the HyperTransport node IDs
535 * which the K8 northbridge parsing fills in. Assume
536 * they are all increased by a constant offset, but in
537 * the same order as the HT nodeids. If that doesn't
538 * result in a usable node fall back to the path for the
541 * This workaround operates directly on the mapping between
542 * APIC ID and NUMA node, assuming certain relationship
543 * between APIC ID, HT node ID and NUMA topology. As going
544 * through CPU mapping may alter the outcome, directly
545 * access __apicid_to_node[].
547 int ht_nodeid = c->initial_apicid;
549 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
550 node = __apicid_to_node[ht_nodeid];
551 /* Pick a nearby node */
552 if (!node_online(node))
553 node = nearby_node(apicid);
555 numa_set_node(cpu, node);
559 static void early_init_amd_mc(struct cpuinfo_x86 *c)
564 /* Multi core CPU? */
565 if (c->extended_cpuid_level < 0x80000008)
568 ecx = cpuid_ecx(0x80000008);
570 c->x86_max_cores = (ecx & 0xff) + 1;
572 /* CPU telling us the core id bits shift? */
573 bits = (ecx >> 12) & 0xF;
575 /* Otherwise recompute */
577 while ((1 << bits) < c->x86_max_cores)
581 c->x86_coreid_bits = bits;
585 static void bsp_init_amd(struct cpuinfo_x86 *c)
587 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
590 (c->x86 == 0x10 && c->x86_model >= 0x2)) {
593 rdmsrl(MSR_K7_HWCR, val);
594 if (!(val & BIT(24)))
595 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
599 if (c->x86 == 0x15) {
600 unsigned long upperbit;
603 cpuid = cpuid_edx(0x80000005);
604 assoc = cpuid >> 16 & 0xff;
605 upperbit = ((cpuid >> 24) << 10) / assoc;
607 va_align.mask = (upperbit - 1) & PAGE_MASK;
608 va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
610 /* A random value per boot for bit slice [12:upper_bit) */
611 va_align.bits = get_random_int() & va_align.mask;
614 if (cpu_has(c, X86_FEATURE_MWAITX))
617 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
620 ecx = cpuid_ecx(0x8000001e);
621 __max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
622 } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
625 rdmsrl(MSR_FAM10H_NODE_ID, value);
626 __max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
629 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
630 !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
631 c->x86 >= 0x15 && c->x86 <= 0x17) {
635 case 0x15: bit = 54; break;
636 case 0x16: bit = 33; break;
637 case 0x17: bit = 10; break;
641 * Try to cache the base value so further operations can
642 * avoid RMW. If that faults, do not enable SSBD.
644 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
645 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
646 setup_force_cpu_cap(X86_FEATURE_SSBD);
647 x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
651 resctrl_cpu_detect(c);
654 static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
659 * BIOS support is required for SME and SEV.
660 * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
661 * the SME physical address space reduction value.
662 * If BIOS has not enabled SME then don't advertise the
663 * SME feature (set in scattered.c).
664 * For SEV: If BIOS has not enabled SEV then don't advertise the
665 * SEV and SEV_ES feature (set in scattered.c).
667 * In all cases, since support for SME and SEV requires long mode,
668 * don't advertise the feature under CONFIG_X86_32.
670 if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
671 /* Check if memory encryption is enabled */
672 rdmsrl(MSR_AMD64_SYSCFG, msr);
673 if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
677 * Always adjust physical address bits. Even though this
678 * will be a value above 32-bits this is still done for
679 * CONFIG_X86_32 so that accurate values are reported.
681 c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
683 if (IS_ENABLED(CONFIG_X86_32))
686 rdmsrl(MSR_K7_HWCR, msr);
687 if (!(msr & MSR_K7_HWCR_SMMLOCK))
693 setup_clear_cpu_cap(X86_FEATURE_SME);
695 setup_clear_cpu_cap(X86_FEATURE_SEV);
696 setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
700 static void early_init_amd(struct cpuinfo_x86 *c)
705 early_init_amd_mc(c);
708 set_cpu_cap(c, X86_FEATURE_K8);
710 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
713 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
714 * with P/T states and does not stop in deep C-states
716 if (c->x86_power & (1 << 8)) {
717 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
718 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
721 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
722 if (c->x86_power & BIT(12))
723 set_cpu_cap(c, X86_FEATURE_ACC_POWER);
725 /* Bit 14 indicates the Runtime Average Power Limit interface. */
726 if (c->x86_power & BIT(14))
727 set_cpu_cap(c, X86_FEATURE_RAPL);
730 set_cpu_cap(c, X86_FEATURE_SYSCALL32);
732 /* Set MTRR capability flag if appropriate */
734 if (c->x86_model == 13 || c->x86_model == 9 ||
735 (c->x86_model == 8 && c->x86_stepping >= 8))
736 set_cpu_cap(c, X86_FEATURE_K6_MTRR);
738 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
740 * ApicID can always be treated as an 8-bit value for AMD APIC versions
741 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
742 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
745 if (boot_cpu_has(X86_FEATURE_APIC)) {
747 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
748 else if (c->x86 >= 0xf) {
749 /* check CPU config space for extended APIC ID */
752 val = read_pci_config(0, 24, 0, 0x68);
753 if ((val >> 17 & 0x3) == 0x3)
754 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
760 * This is only needed to tell the kernel whether to use VMCALL
761 * and VMMCALL. VMMCALL is never executed except under virt, so
762 * we can set it unconditionally.
764 set_cpu_cap(c, X86_FEATURE_VMMCALL);
766 /* F16h erratum 793, CVE-2013-6885 */
767 if (c->x86 == 0x16 && c->x86_model <= 0xf)
768 msr_set_bit(MSR_AMD64_LS_CFG, 15);
771 * Check whether the machine is affected by erratum 400. This is
772 * used to select the proper idle routine and to enable the check
773 * whether the machine is affected in arch_post_acpi_init(), which
774 * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
776 if (cpu_has_amd_erratum(c, amd_erratum_400))
777 set_cpu_bug(c, X86_BUG_AMD_E400);
779 early_detect_mem_encrypt(c);
781 /* Re-enable TopologyExtensions if switched off by BIOS */
782 if (c->x86 == 0x15 &&
783 (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
784 !cpu_has(c, X86_FEATURE_TOPOEXT)) {
786 if (msr_set_bit(0xc0011005, 54) > 0) {
787 rdmsrl(0xc0011005, value);
788 if (value & BIT_64(54)) {
789 set_cpu_cap(c, X86_FEATURE_TOPOEXT);
790 pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
795 if (cpu_has(c, X86_FEATURE_TOPOEXT))
796 smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
799 static void init_amd_k8(struct cpuinfo_x86 *c)
804 /* On C+ stepping K8 rep microcode works well for copy/memset */
805 level = cpuid_eax(1);
806 if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
807 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
810 * Some BIOSes incorrectly force this feature, but only K8 revision D
811 * (model = 0x14) and later actually support it.
812 * (AMD Erratum #110, docId: 25759).
814 if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
815 clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
816 if (!rdmsrl_amd_safe(0xc001100d, &value)) {
817 value &= ~BIT_64(32);
818 wrmsrl_amd_safe(0xc001100d, value);
822 if (!c->x86_model_id[0])
823 strcpy(c->x86_model_id, "Hammer");
827 * Disable TLB flush filter by setting HWCR.FFDIS on K8
828 * bit 6 of msr C001_0015
830 * Errata 63 for SH-B3 steppings
831 * Errata 122 for all steppings (F+ have it disabled by default)
833 msr_set_bit(MSR_K7_HWCR, 6);
835 set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
838 static void init_amd_gh(struct cpuinfo_x86 *c)
840 #ifdef CONFIG_MMCONF_FAM10H
841 /* do this for boot cpu */
842 if (c == &boot_cpu_data)
843 check_enable_amd_mmconf_dmi();
845 fam10h_check_enable_mmcfg();
849 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
850 * is always needed when GART is enabled, even in a kernel which has no
851 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
852 * If it doesn't, we do it here as suggested by the BKDG.
854 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
856 msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
859 * On family 10h BIOS may not have properly enabled WC+ support, causing
860 * it to be converted to CD memtype. This may result in performance
861 * degradation for certain nested-paging guests. Prevent this conversion
862 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
864 * NOTE: we want to use the _safe accessors so as not to #GP kvm
865 * guests on older kvm hosts.
867 msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
869 if (cpu_has_amd_erratum(c, amd_erratum_383))
870 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
873 static void init_amd_ln(struct cpuinfo_x86 *c)
876 * Apply erratum 665 fix unconditionally so machines without a BIOS
879 msr_set_bit(MSR_AMD64_DE_CFG, 31);
882 static bool rdrand_force;
884 static int __init rdrand_cmdline(char *str)
889 if (!strcmp(str, "force"))
896 early_param("rdrand", rdrand_cmdline);
898 static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
901 * Saving of the MSR used to hide the RDRAND support during
902 * suspend/resume is done by arch/x86/power/cpu.c, which is
903 * dependent on CONFIG_PM_SLEEP.
905 if (!IS_ENABLED(CONFIG_PM_SLEEP))
909 * The nordrand option can clear X86_FEATURE_RDRAND, so check for
910 * RDRAND support using the CPUID function directly.
912 if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
915 msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
918 * Verify that the CPUID change has occurred in case the kernel is
919 * running virtualized and the hypervisor doesn't support the MSR.
921 if (cpuid_ecx(1) & BIT(30)) {
922 pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
926 clear_cpu_cap(c, X86_FEATURE_RDRAND);
927 pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
930 static void init_amd_jg(struct cpuinfo_x86 *c)
933 * Some BIOS implementations do not restore proper RDRAND support
934 * across suspend and resume. Check on whether to hide the RDRAND
935 * instruction support via CPUID.
937 clear_rdrand_cpuid_bit(c);
940 static void init_amd_bd(struct cpuinfo_x86 *c)
945 * The way access filter has a performance penalty on some workloads.
946 * Disable it on the affected CPUs.
948 if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
949 if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
951 wrmsrl_safe(MSR_F15H_IC_CFG, value);
956 * Some BIOS implementations do not restore proper RDRAND support
957 * across suspend and resume. Check on whether to hide the RDRAND
958 * instruction support via CPUID.
960 clear_rdrand_cpuid_bit(c);
963 void init_spectral_chicken(struct cpuinfo_x86 *c)
965 #ifdef CONFIG_CPU_UNRET_ENTRY
969 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
971 * This suppresses speculation from the middle of a basic block, i.e. it
972 * suppresses non-branch predictions.
974 * We use STIBP as a heuristic to filter out Zen2 from the rest of F17H
976 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && cpu_has(c, X86_FEATURE_AMD_STIBP)) {
977 if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
978 value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
979 wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
984 * Work around Erratum 1386. The XSAVES instruction malfunctions in
985 * certain circumstances on Zen1/2 uarch, and not all parts have had
986 * updated microcode at the time of writing (March 2023).
988 * Affected parts all have no supervisor XSAVE states, meaning that
989 * the XSAVEC instruction (which works fine) is equivalent.
991 clear_cpu_cap(c, X86_FEATURE_XSAVES);
994 static void init_amd_zn(struct cpuinfo_x86 *c)
996 set_cpu_cap(c, X86_FEATURE_ZEN);
999 node_reclaim_distance = 32;
1002 /* Fix up CPUID bits, but only if not virtualised. */
1003 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
1005 /* Erratum 1076: CPB feature bit not being set in CPUID. */
1006 if (!cpu_has(c, X86_FEATURE_CPB))
1007 set_cpu_cap(c, X86_FEATURE_CPB);
1010 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
1011 * Branch Type Confusion, but predate the allocation of the
1014 if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
1015 set_cpu_cap(c, X86_FEATURE_BTC_NO);
1019 static bool cpu_has_zenbleed_microcode(void)
1023 switch (boot_cpu_data.x86_model) {
1024 case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
1025 case 0x60 ... 0x67: good_rev = 0x0860010b; break;
1026 case 0x68 ... 0x6f: good_rev = 0x08608105; break;
1027 case 0x70 ... 0x7f: good_rev = 0x08701032; break;
1028 case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
1035 if (boot_cpu_data.microcode < good_rev)
1041 static void zenbleed_check(struct cpuinfo_x86 *c)
1043 if (!cpu_has_amd_erratum(c, amd_zenbleed))
1046 if (cpu_has(c, X86_FEATURE_HYPERVISOR))
1049 if (!cpu_has(c, X86_FEATURE_AVX))
1052 if (!cpu_has_zenbleed_microcode()) {
1053 pr_notice_once("Zenbleed: /*(DEBLOBBED)*/ for the most optimal fix\n");
1054 msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1056 msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1060 static void init_amd(struct cpuinfo_x86 *c)
1065 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
1066 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
1068 clear_cpu_cap(c, 0*32+31);
1071 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
1073 /* get apicid instead of initial apic id from cpuid */
1074 c->apicid = hard_smp_processor_id();
1076 /* K6s reports MCEs but don't actually have all the MSRs */
1078 clear_cpu_cap(c, X86_FEATURE_MCE);
1081 case 4: init_amd_k5(c); break;
1082 case 5: init_amd_k6(c); break;
1083 case 6: init_amd_k7(c); break;
1084 case 0xf: init_amd_k8(c); break;
1085 case 0x10: init_amd_gh(c); break;
1086 case 0x12: init_amd_ln(c); break;
1087 case 0x15: init_amd_bd(c); break;
1088 case 0x16: init_amd_jg(c); break;
1089 case 0x17: init_spectral_chicken(c);
1091 case 0x19: init_amd_zn(c); break;
1095 * Enable workaround for FXSAVE leak on CPUs
1096 * without a XSaveErPtr feature
1098 if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
1099 set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
1101 cpu_detect_cache_sizes(c);
1104 amd_get_topology(c);
1105 srat_detect_node(c);
1108 init_amd_cacheinfo(c);
1110 if (cpu_has(c, X86_FEATURE_XMM2)) {
1112 * Use LFENCE for execution serialization. On families which
1113 * don't have that MSR, LFENCE is already serializing.
1114 * msr_set_bit() uses the safe accessors, too, even if the MSR
1117 msr_set_bit(MSR_AMD64_DE_CFG,
1118 MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
1120 /* A serializing LFENCE stops RDTSC speculation */
1121 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
1125 * Family 0x12 and above processors have APIC timer
1126 * running in deep C states.
1129 set_cpu_cap(c, X86_FEATURE_ARAT);
1131 /* 3DNow or LM implies PREFETCHW */
1132 if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
1133 if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
1134 set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
1136 /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
1137 if (!cpu_has(c, X86_FEATURE_XENPV))
1138 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
1141 * Turn on the Instructions Retired free counter on machines not
1142 * susceptible to erratum #1054 "Instructions Retired Performance
1143 * Counter May Be Inaccurate".
1145 if (cpu_has(c, X86_FEATURE_IRPERF) &&
1146 !cpu_has_amd_erratum(c, amd_erratum_1054))
1147 msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
1149 check_null_seg_clears_base(c);
1153 if (cpu_has_amd_erratum(c, amd_div0)) {
1154 pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
1155 setup_force_cpu_bug(X86_BUG_DIV0);
1158 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
1159 cpu_has_amd_erratum(c, amd_erratum_1485))
1160 msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
1163 #ifdef CONFIG_X86_32
1164 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
1166 /* AMD errata T13 (order #21922) */
1169 if (c->x86_model == 3 && c->x86_stepping == 0)
1171 /* Tbird rev A1/A2 */
1172 if (c->x86_model == 4 &&
1173 (c->x86_stepping == 0 || c->x86_stepping == 1))
1180 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1182 u32 ebx, eax, ecx, edx;
1188 if (c->extended_cpuid_level < 0x80000006)
1191 cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1193 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1194 tlb_lli_4k[ENTRIES] = ebx & mask;
1197 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1198 * characteristics from the CPUID function 0x80000005 instead.
1200 if (c->x86 == 0xf) {
1201 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1205 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1206 if (!((eax >> 16) & mask))
1207 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1209 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1211 /* a 4M entry uses two 2M entries */
1212 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1214 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1215 if (!(eax & mask)) {
1217 if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1218 tlb_lli_2m[ENTRIES] = 1024;
1220 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1221 tlb_lli_2m[ENTRIES] = eax & 0xff;
1224 tlb_lli_2m[ENTRIES] = eax & mask;
1226 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1229 static const struct cpu_dev amd_cpu_dev = {
1231 .c_ident = { "AuthenticAMD" },
1232 #ifdef CONFIG_X86_32
1234 { .family = 4, .model_names =
1237 [7] = "486 DX/2-WB",
1239 [9] = "486 DX/4-WB",
1245 .legacy_cache_size = amd_size_cache,
1247 .c_early_init = early_init_amd,
1248 .c_detect_tlb = cpu_detect_tlb_amd,
1249 .c_bsp_init = bsp_init_amd,
1251 .c_x86_vendor = X86_VENDOR_AMD,
1254 cpu_dev_register(amd_cpu_dev);
1256 void set_dr_addr_mask(unsigned long mask, int dr)
1258 if (!boot_cpu_has(X86_FEATURE_BPEXT))
1263 wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
1268 wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
1275 u32 amd_get_highest_perf(void)
1277 struct cpuinfo_x86 *c = &boot_cpu_data;
1279 if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
1280 (c->x86_model >= 0x70 && c->x86_model < 0x80)))
1283 if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
1284 (c->x86_model >= 0x40 && c->x86_model < 0x70)))
1289 EXPORT_SYMBOL_GPL(amd_get_highest_perf);
1291 bool cpu_has_ibpb_brtype_microcode(void)
1293 switch (boot_cpu_data.x86) {
1294 /* Zen1/2 IBPB flushes branch type predictions too. */
1296 return boot_cpu_has(X86_FEATURE_AMD_IBPB);
1298 /* Poke the MSR bit on Zen3/4 to check its presence. */
1299 if (!wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
1300 setup_force_cpu_cap(X86_FEATURE_SBPB);
1310 static void zenbleed_check_cpu(void *unused)
1312 struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
1317 void amd_check_microcode(void)
1319 on_each_cpu(zenbleed_check_cpu, NULL, 1);
1323 * Issue a DIV 0/1 insn to clear any division data from previous DIV
1326 void noinstr amd_clear_divider(void)
1328 asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
1329 :: "a" (0), "d" (0), "r" (1));
1331 EXPORT_SYMBOL_GPL(amd_clear_divider);