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>
26 # include <asm/mmconfig.h>
31 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
36 WARN_ONCE((boot_cpu_data.x86 != 0xf),
37 "%s should only be used on K8!\n", __func__);
42 err = rdmsr_safe_regs(gprs);
44 *p = gprs[0] | ((u64)gprs[2] << 32);
49 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
53 WARN_ONCE((boot_cpu_data.x86 != 0xf),
54 "%s should only be used on K8!\n", __func__);
61 return wrmsr_safe_regs(gprs);
65 * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
66 * misexecution of code under Linux. Owners of such processors should
67 * contact AMD for precise details and a CPU swap.
69 * See http://www.multimania.com/poulot/k6bug.html
70 * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
71 * (Publication # 21266 Issue Date: August 1998)
73 * The following test is erm.. interesting. AMD neglected to up
74 * the chip setting when fixing the bug but they also tweaked some
75 * performance at the same time..
79 extern __visible void vide(void);
82 ".type vide, @function\n"
87 static void init_amd_k5(struct cpuinfo_x86 *c)
91 * General Systems BIOSen alias the cpu frequency registers
92 * of the Elan at 0x000df000. Unfortunately, one of the Linux
93 * drivers subsequently pokes it, and changes the CPU speed.
94 * Workaround : Remove the unneeded alias.
96 #define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
97 #define CBAR_ENB (0x80000000)
98 #define CBAR_KEY (0X000000CB)
99 if (c->x86_model == 9 || c->x86_model == 10) {
100 if (inl(CBAR) & CBAR_ENB)
101 outl(0 | CBAR_KEY, CBAR);
106 static void init_amd_k6(struct cpuinfo_x86 *c)
110 int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
112 if (c->x86_model < 6) {
113 /* Based on AMD doc 20734R - June 2000 */
114 if (c->x86_model == 0) {
115 clear_cpu_cap(c, X86_FEATURE_APIC);
116 set_cpu_cap(c, X86_FEATURE_PGE);
121 if (c->x86_model == 6 && c->x86_stepping == 1) {
122 const int K6_BUG_LOOP = 1000000;
124 void (*f_vide)(void);
127 pr_info("AMD K6 stepping B detected - ");
130 * It looks like AMD fixed the 2.6.2 bug and improved indirect
131 * calls at the same time.
136 OPTIMIZER_HIDE_VAR(f_vide);
143 if (d > 20*K6_BUG_LOOP)
144 pr_cont("system stability may be impaired when more than 32 MB are used.\n");
146 pr_cont("probably OK (after B9730xxxx).\n");
149 /* K6 with old style WHCR */
150 if (c->x86_model < 8 ||
151 (c->x86_model == 8 && c->x86_stepping < 8)) {
152 /* We can only write allocate on the low 508Mb */
156 rdmsr(MSR_K6_WHCR, l, h);
157 if ((l&0x0000FFFF) == 0) {
159 l = (1<<0)|((mbytes/4)<<1);
160 local_irq_save(flags);
162 wrmsr(MSR_K6_WHCR, l, h);
163 local_irq_restore(flags);
164 pr_info("Enabling old style K6 write allocation for %d Mb\n",
170 if ((c->x86_model == 8 && c->x86_stepping > 7) ||
171 c->x86_model == 9 || c->x86_model == 13) {
172 /* The more serious chips .. */
177 rdmsr(MSR_K6_WHCR, l, h);
178 if ((l&0xFFFF0000) == 0) {
180 l = ((mbytes>>2)<<22)|(1<<16);
181 local_irq_save(flags);
183 wrmsr(MSR_K6_WHCR, l, h);
184 local_irq_restore(flags);
185 pr_info("Enabling new style K6 write allocation for %d Mb\n",
192 if (c->x86_model == 10) {
193 /* AMD Geode LX is model 10 */
194 /* placeholder for any needed mods */
200 static void init_amd_k7(struct cpuinfo_x86 *c)
206 * Bit 15 of Athlon specific MSR 15, needs to be 0
207 * to enable SSE on Palomino/Morgan/Barton CPU's.
208 * If the BIOS didn't enable it already, enable it here.
210 if (c->x86_model >= 6 && c->x86_model <= 10) {
211 if (!cpu_has(c, X86_FEATURE_XMM)) {
212 pr_info("Enabling disabled K7/SSE Support.\n");
213 msr_clear_bit(MSR_K7_HWCR, 15);
214 set_cpu_cap(c, X86_FEATURE_XMM);
219 * It's been determined by AMD that Athlons since model 8 stepping 1
220 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
221 * As per AMD technical note 27212 0.2
223 if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
224 rdmsr(MSR_K7_CLK_CTL, l, h);
225 if ((l & 0xfff00000) != 0x20000000) {
226 pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
227 l, ((l & 0x000fffff)|0x20000000));
228 wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
232 /* calling is from identify_secondary_cpu() ? */
237 * Certain Athlons might work (for various values of 'work') in SMP
238 * but they are not certified as MP capable.
240 /* Athlon 660/661 is valid. */
241 if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
242 (c->x86_stepping == 1)))
245 /* Duron 670 is valid */
246 if ((c->x86_model == 7) && (c->x86_stepping == 0))
250 * Athlon 662, Duron 671, and Athlon >model 7 have capability
251 * bit. It's worth noting that the A5 stepping (662) of some
252 * Athlon XP's have the MP bit set.
253 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
256 if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
257 ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
259 if (cpu_has(c, X86_FEATURE_MP))
262 /* If we get here, not a certified SMP capable AMD system. */
265 * Don't taint if we are running SMP kernel on a single non-MP
268 WARN_ONCE(1, "WARNING: This combination of AMD"
269 " processors is not suitable for SMP.\n");
270 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
276 * To workaround broken NUMA config. Read the comment in
277 * srat_detect_node().
279 static int nearby_node(int apicid)
283 for (i = apicid - 1; i >= 0; i--) {
284 node = __apicid_to_node[i];
285 if (node != NUMA_NO_NODE && node_online(node))
288 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
289 node = __apicid_to_node[i];
290 if (node != NUMA_NO_NODE && node_online(node))
293 return first_node(node_online_map); /* Shouldn't happen */
297 static void srat_detect_node(struct cpuinfo_x86 *c)
300 int cpu = smp_processor_id();
302 unsigned apicid = c->topo.apicid;
304 node = numa_cpu_node(cpu);
305 if (node == NUMA_NO_NODE)
306 node = per_cpu_llc_id(cpu);
309 * On multi-fabric platform (e.g. Numascale NumaChip) a
310 * platform-specific handler needs to be called to fixup some
313 if (x86_cpuinit.fixup_cpu_id)
314 x86_cpuinit.fixup_cpu_id(c, node);
316 if (!node_online(node)) {
318 * Two possibilities here:
320 * - The CPU is missing memory and no node was created. In
321 * that case try picking one from a nearby CPU.
323 * - The APIC IDs differ from the HyperTransport node IDs
324 * which the K8 northbridge parsing fills in. Assume
325 * they are all increased by a constant offset, but in
326 * the same order as the HT nodeids. If that doesn't
327 * result in a usable node fall back to the path for the
330 * This workaround operates directly on the mapping between
331 * APIC ID and NUMA node, assuming certain relationship
332 * between APIC ID, HT node ID and NUMA topology. As going
333 * through CPU mapping may alter the outcome, directly
334 * access __apicid_to_node[].
336 int ht_nodeid = c->topo.initial_apicid;
338 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
339 node = __apicid_to_node[ht_nodeid];
340 /* Pick a nearby node */
341 if (!node_online(node))
342 node = nearby_node(apicid);
344 numa_set_node(cpu, node);
348 static void bsp_determine_snp(struct cpuinfo_x86 *c)
350 #ifdef CONFIG_ARCH_HAS_CC_PLATFORM
351 cc_vendor = CC_VENDOR_AMD;
353 if (cpu_has(c, X86_FEATURE_SEV_SNP)) {
355 * RMP table entry format is not architectural and is defined by the
356 * per-processor PPR. Restrict SNP support on the known CPU models
357 * for which the RMP table entry format is currently defined for.
359 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
360 c->x86 >= 0x19 && snp_probe_rmptable_info()) {
361 cc_platform_set(CC_ATTR_HOST_SEV_SNP);
363 setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
364 cc_platform_clear(CC_ATTR_HOST_SEV_SNP);
370 static void bsp_init_amd(struct cpuinfo_x86 *c)
372 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
375 (c->x86 == 0x10 && c->x86_model >= 0x2)) {
378 rdmsrl(MSR_K7_HWCR, val);
379 if (!(val & BIT(24)))
380 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
384 if (c->x86 == 0x15) {
385 unsigned long upperbit;
388 cpuid = cpuid_edx(0x80000005);
389 assoc = cpuid >> 16 & 0xff;
390 upperbit = ((cpuid >> 24) << 10) / assoc;
392 va_align.mask = (upperbit - 1) & PAGE_MASK;
393 va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
395 /* A random value per boot for bit slice [12:upper_bit) */
396 va_align.bits = get_random_u32() & va_align.mask;
399 if (cpu_has(c, X86_FEATURE_MWAITX))
402 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
403 !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
404 c->x86 >= 0x15 && c->x86 <= 0x17) {
408 case 0x15: bit = 54; break;
409 case 0x16: bit = 33; break;
410 case 0x17: bit = 10; break;
414 * Try to cache the base value so further operations can
415 * avoid RMW. If that faults, do not enable SSBD.
417 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
418 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
419 setup_force_cpu_cap(X86_FEATURE_SSBD);
420 x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
424 resctrl_cpu_detect(c);
426 /* Figure out Zen generations: */
429 switch (c->x86_model) {
432 setup_force_cpu_cap(X86_FEATURE_ZEN1);
438 setup_force_cpu_cap(X86_FEATURE_ZEN2);
446 switch (c->x86_model) {
449 setup_force_cpu_cap(X86_FEATURE_ZEN3);
453 setup_force_cpu_cap(X86_FEATURE_ZEN4);
461 switch (c->x86_model) {
466 setup_force_cpu_cap(X86_FEATURE_ZEN5);
477 bsp_determine_snp(c);
481 WARN_ONCE(1, "Family 0x%x, model: 0x%x??\n", c->x86, c->x86_model);
484 static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
489 * BIOS support is required for SME and SEV.
490 * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
491 * the SME physical address space reduction value.
492 * If BIOS has not enabled SME then don't advertise the
493 * SME feature (set in scattered.c).
494 * If the kernel has not enabled SME via any means then
495 * don't advertise the SME feature.
496 * For SEV: If BIOS has not enabled SEV then don't advertise SEV and
497 * any additional functionality based on it.
499 * In all cases, since support for SME and SEV requires long mode,
500 * don't advertise the feature under CONFIG_X86_32.
502 if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
503 /* Check if memory encryption is enabled */
504 rdmsrl(MSR_AMD64_SYSCFG, msr);
505 if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
509 * Always adjust physical address bits. Even though this
510 * will be a value above 32-bits this is still done for
511 * CONFIG_X86_32 so that accurate values are reported.
513 c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
515 if (IS_ENABLED(CONFIG_X86_32))
519 setup_clear_cpu_cap(X86_FEATURE_SME);
521 rdmsrl(MSR_K7_HWCR, msr);
522 if (!(msr & MSR_K7_HWCR_SMMLOCK))
528 setup_clear_cpu_cap(X86_FEATURE_SME);
530 setup_clear_cpu_cap(X86_FEATURE_SEV);
531 setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
532 setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
536 static void early_init_amd(struct cpuinfo_x86 *c)
541 set_cpu_cap(c, X86_FEATURE_K8);
543 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
546 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
547 * with P/T states and does not stop in deep C-states
549 if (c->x86_power & (1 << 8)) {
550 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
551 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
554 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
555 if (c->x86_power & BIT(12))
556 set_cpu_cap(c, X86_FEATURE_ACC_POWER);
558 /* Bit 14 indicates the Runtime Average Power Limit interface. */
559 if (c->x86_power & BIT(14))
560 set_cpu_cap(c, X86_FEATURE_RAPL);
563 set_cpu_cap(c, X86_FEATURE_SYSCALL32);
565 /* Set MTRR capability flag if appropriate */
567 if (c->x86_model == 13 || c->x86_model == 9 ||
568 (c->x86_model == 8 && c->x86_stepping >= 8))
569 set_cpu_cap(c, X86_FEATURE_K6_MTRR);
571 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
573 * ApicID can always be treated as an 8-bit value for AMD APIC versions
574 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
575 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
578 if (boot_cpu_has(X86_FEATURE_APIC)) {
580 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
581 else if (c->x86 >= 0xf) {
582 /* check CPU config space for extended APIC ID */
585 val = read_pci_config(0, 24, 0, 0x68);
586 if ((val >> 17 & 0x3) == 0x3)
587 set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
593 * This is only needed to tell the kernel whether to use VMCALL
594 * and VMMCALL. VMMCALL is never executed except under virt, so
595 * we can set it unconditionally.
597 set_cpu_cap(c, X86_FEATURE_VMMCALL);
599 /* F16h erratum 793, CVE-2013-6885 */
600 if (c->x86 == 0x16 && c->x86_model <= 0xf)
601 msr_set_bit(MSR_AMD64_LS_CFG, 15);
603 early_detect_mem_encrypt(c);
605 if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
606 if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
607 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
608 else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
609 setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
610 setup_force_cpu_cap(X86_FEATURE_SBPB);
615 static void init_amd_k8(struct cpuinfo_x86 *c)
620 /* On C+ stepping K8 rep microcode works well for copy/memset */
621 level = cpuid_eax(1);
622 if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
623 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
626 * Some BIOSes incorrectly force this feature, but only K8 revision D
627 * (model = 0x14) and later actually support it.
628 * (AMD Erratum #110, docId: 25759).
630 if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
631 clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
632 if (!rdmsrl_amd_safe(0xc001100d, &value)) {
633 value &= ~BIT_64(32);
634 wrmsrl_amd_safe(0xc001100d, value);
638 if (!c->x86_model_id[0])
639 strcpy(c->x86_model_id, "Hammer");
643 * Disable TLB flush filter by setting HWCR.FFDIS on K8
644 * bit 6 of msr C001_0015
646 * Errata 63 for SH-B3 steppings
647 * Errata 122 for all steppings (F+ have it disabled by default)
649 msr_set_bit(MSR_K7_HWCR, 6);
651 set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
654 * Check models and steppings affected by erratum 400. This is
655 * used to select the proper idle routine and to enable the
656 * check whether the machine is affected in arch_post_acpi_subsys_init()
657 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
659 if (c->x86_model > 0x41 ||
660 (c->x86_model == 0x41 && c->x86_stepping >= 0x2))
661 setup_force_cpu_bug(X86_BUG_AMD_E400);
664 static void init_amd_gh(struct cpuinfo_x86 *c)
666 #ifdef CONFIG_MMCONF_FAM10H
667 /* do this for boot cpu */
668 if (c == &boot_cpu_data)
669 check_enable_amd_mmconf_dmi();
671 fam10h_check_enable_mmcfg();
675 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
676 * is always needed when GART is enabled, even in a kernel which has no
677 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
678 * If it doesn't, we do it here as suggested by the BKDG.
680 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
682 msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
685 * On family 10h BIOS may not have properly enabled WC+ support, causing
686 * it to be converted to CD memtype. This may result in performance
687 * degradation for certain nested-paging guests. Prevent this conversion
688 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
690 * NOTE: we want to use the _safe accessors so as not to #GP kvm
691 * guests on older kvm hosts.
693 msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
695 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
698 * Check models and steppings affected by erratum 400. This is
699 * used to select the proper idle routine and to enable the
700 * check whether the machine is affected in arch_post_acpi_subsys_init()
701 * which sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
703 if (c->x86_model > 0x2 ||
704 (c->x86_model == 0x2 && c->x86_stepping >= 0x1))
705 setup_force_cpu_bug(X86_BUG_AMD_E400);
708 static void init_amd_ln(struct cpuinfo_x86 *c)
711 * Apply erratum 665 fix unconditionally so machines without a BIOS
714 msr_set_bit(MSR_AMD64_DE_CFG, 31);
717 static bool rdrand_force;
719 static int __init rdrand_cmdline(char *str)
724 if (!strcmp(str, "force"))
731 early_param("rdrand", rdrand_cmdline);
733 static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
736 * Saving of the MSR used to hide the RDRAND support during
737 * suspend/resume is done by arch/x86/power/cpu.c, which is
738 * dependent on CONFIG_PM_SLEEP.
740 if (!IS_ENABLED(CONFIG_PM_SLEEP))
744 * The self-test can clear X86_FEATURE_RDRAND, so check for
745 * RDRAND support using the CPUID function directly.
747 if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
750 msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
753 * Verify that the CPUID change has occurred in case the kernel is
754 * running virtualized and the hypervisor doesn't support the MSR.
756 if (cpuid_ecx(1) & BIT(30)) {
757 pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
761 clear_cpu_cap(c, X86_FEATURE_RDRAND);
762 pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
765 static void init_amd_jg(struct cpuinfo_x86 *c)
768 * Some BIOS implementations do not restore proper RDRAND support
769 * across suspend and resume. Check on whether to hide the RDRAND
770 * instruction support via CPUID.
772 clear_rdrand_cpuid_bit(c);
775 static void init_amd_bd(struct cpuinfo_x86 *c)
780 * The way access filter has a performance penalty on some workloads.
781 * Disable it on the affected CPUs.
783 if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
784 if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
786 wrmsrl_safe(MSR_F15H_IC_CFG, value);
791 * Some BIOS implementations do not restore proper RDRAND support
792 * across suspend and resume. Check on whether to hide the RDRAND
793 * instruction support via CPUID.
795 clear_rdrand_cpuid_bit(c);
798 static void fix_erratum_1386(struct cpuinfo_x86 *c)
801 * Work around Erratum 1386. The XSAVES instruction malfunctions in
802 * certain circumstances on Zen1/2 uarch, and not all parts have had
803 * updated microcode at the time of writing (March 2023).
805 * Affected parts all have no supervisor XSAVE states, meaning that
806 * the XSAVEC instruction (which works fine) is equivalent.
808 clear_cpu_cap(c, X86_FEATURE_XSAVES);
811 void init_spectral_chicken(struct cpuinfo_x86 *c)
813 #ifdef CONFIG_MITIGATION_UNRET_ENTRY
817 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
819 * This suppresses speculation from the middle of a basic block, i.e. it
820 * suppresses non-branch predictions.
822 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
823 if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
824 value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
825 wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
831 static void init_amd_zen_common(void)
833 setup_force_cpu_cap(X86_FEATURE_ZEN);
835 node_reclaim_distance = 32;
839 static void init_amd_zen1(struct cpuinfo_x86 *c)
843 /* Fix up CPUID bits, but only if not virtualised. */
844 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
846 /* Erratum 1076: CPB feature bit not being set in CPUID. */
847 if (!cpu_has(c, X86_FEATURE_CPB))
848 set_cpu_cap(c, X86_FEATURE_CPB);
851 pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
852 setup_force_cpu_bug(X86_BUG_DIV0);
855 static bool cpu_has_zenbleed_microcode(void)
859 switch (boot_cpu_data.x86_model) {
860 case 0x30 ... 0x3f: good_rev = 0x0830107b; break;
861 case 0x60 ... 0x67: good_rev = 0x0860010c; break;
862 case 0x68 ... 0x6f: good_rev = 0x08608107; break;
863 case 0x70 ... 0x7f: good_rev = 0x08701033; break;
864 case 0xa0 ... 0xaf: good_rev = 0x08a00009; break;
870 if (boot_cpu_data.microcode < good_rev)
876 static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
878 if (cpu_has(c, X86_FEATURE_HYPERVISOR))
881 if (!cpu_has(c, X86_FEATURE_AVX))
884 if (!cpu_has_zenbleed_microcode()) {
885 pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
886 msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
888 msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
892 static void init_amd_zen2(struct cpuinfo_x86 *c)
894 init_spectral_chicken(c);
896 zen2_zenbleed_check(c);
899 static void init_amd_zen3(struct cpuinfo_x86 *c)
901 if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
903 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
904 * Branch Type Confusion, but predate the allocation of the
907 if (!cpu_has(c, X86_FEATURE_BTC_NO))
908 set_cpu_cap(c, X86_FEATURE_BTC_NO);
912 static void init_amd_zen4(struct cpuinfo_x86 *c)
914 if (!cpu_has(c, X86_FEATURE_HYPERVISOR))
915 msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
918 static void init_amd_zen5(struct cpuinfo_x86 *c)
922 static void init_amd(struct cpuinfo_x86 *c)
929 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
930 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
932 clear_cpu_cap(c, 0*32+31);
935 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
937 /* AMD FSRM also implies FSRS */
938 if (cpu_has(c, X86_FEATURE_FSRM))
939 set_cpu_cap(c, X86_FEATURE_FSRS);
941 /* K6s reports MCEs but don't actually have all the MSRs */
943 clear_cpu_cap(c, X86_FEATURE_MCE);
946 case 4: init_amd_k5(c); break;
947 case 5: init_amd_k6(c); break;
948 case 6: init_amd_k7(c); break;
949 case 0xf: init_amd_k8(c); break;
950 case 0x10: init_amd_gh(c); break;
951 case 0x12: init_amd_ln(c); break;
952 case 0x15: init_amd_bd(c); break;
953 case 0x16: init_amd_jg(c); break;
957 * Save up on some future enablement work and do common Zen
961 init_amd_zen_common();
963 if (boot_cpu_has(X86_FEATURE_ZEN1))
965 else if (boot_cpu_has(X86_FEATURE_ZEN2))
967 else if (boot_cpu_has(X86_FEATURE_ZEN3))
969 else if (boot_cpu_has(X86_FEATURE_ZEN4))
971 else if (boot_cpu_has(X86_FEATURE_ZEN5))
975 * Enable workaround for FXSAVE leak on CPUs
976 * without a XSaveErPtr feature
978 if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
979 set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
981 cpu_detect_cache_sizes(c);
985 init_amd_cacheinfo(c);
987 if (cpu_has(c, X86_FEATURE_SVM)) {
988 rdmsrl(MSR_VM_CR, vm_cr);
989 if (vm_cr & SVM_VM_CR_SVM_DIS_MASK) {
990 pr_notice_once("SVM disabled (by BIOS) in MSR_VM_CR\n");
991 clear_cpu_cap(c, X86_FEATURE_SVM);
995 if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) {
997 * Use LFENCE for execution serialization. On families which
998 * don't have that MSR, LFENCE is already serializing.
999 * msr_set_bit() uses the safe accessors, too, even if the MSR
1002 msr_set_bit(MSR_AMD64_DE_CFG,
1003 MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
1005 /* A serializing LFENCE stops RDTSC speculation */
1006 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
1010 * Family 0x12 and above processors have APIC timer
1011 * running in deep C states.
1014 set_cpu_cap(c, X86_FEATURE_ARAT);
1016 /* 3DNow or LM implies PREFETCHW */
1017 if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
1018 if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
1019 set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
1021 /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
1022 if (!cpu_feature_enabled(X86_FEATURE_XENPV))
1023 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
1026 * Turn on the Instructions Retired free counter on machines not
1027 * susceptible to erratum #1054 "Instructions Retired Performance
1028 * Counter May Be Inaccurate".
1030 if (cpu_has(c, X86_FEATURE_IRPERF) &&
1031 (boot_cpu_has(X86_FEATURE_ZEN1) && c->x86_model > 0x2f))
1032 msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
1034 check_null_seg_clears_base(c);
1037 * Make sure EFER[AIBRSE - Automatic IBRS Enable] is set. The APs are brought up
1038 * using the trampoline code and as part of it, MSR_EFER gets prepared there in
1039 * order to be replicated onto them. Regardless, set it here again, if not set,
1040 * to protect against any future refactoring/code reorganization which might
1041 * miss setting this important bit.
1043 if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
1044 cpu_has(c, X86_FEATURE_AUTOIBRS))
1045 WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
1047 /* AMD CPUs don't need fencing after x2APIC/TSC_DEADLINE MSR writes. */
1048 clear_cpu_cap(c, X86_FEATURE_APIC_MSRS_FENCE);
1051 #ifdef CONFIG_X86_32
1052 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
1054 /* AMD errata T13 (order #21922) */
1057 if (c->x86_model == 3 && c->x86_stepping == 0)
1059 /* Tbird rev A1/A2 */
1060 if (c->x86_model == 4 &&
1061 (c->x86_stepping == 0 || c->x86_stepping == 1))
1068 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1070 u32 ebx, eax, ecx, edx;
1076 if (c->extended_cpuid_level < 0x80000006)
1079 cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1081 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1082 tlb_lli_4k[ENTRIES] = ebx & mask;
1085 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1086 * characteristics from the CPUID function 0x80000005 instead.
1088 if (c->x86 == 0xf) {
1089 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1093 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1094 if (!((eax >> 16) & mask))
1095 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1097 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1099 /* a 4M entry uses two 2M entries */
1100 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1102 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1103 if (!(eax & mask)) {
1105 if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1106 tlb_lli_2m[ENTRIES] = 1024;
1108 cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1109 tlb_lli_2m[ENTRIES] = eax & 0xff;
1112 tlb_lli_2m[ENTRIES] = eax & mask;
1114 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1117 static const struct cpu_dev amd_cpu_dev = {
1119 .c_ident = { "AuthenticAMD" },
1120 #ifdef CONFIG_X86_32
1122 { .family = 4, .model_names =
1125 [7] = "486 DX/2-WB",
1127 [9] = "486 DX/4-WB",
1133 .legacy_cache_size = amd_size_cache,
1135 .c_early_init = early_init_amd,
1136 .c_detect_tlb = cpu_detect_tlb_amd,
1137 .c_bsp_init = bsp_init_amd,
1139 .c_x86_vendor = X86_VENDOR_AMD,
1142 cpu_dev_register(amd_cpu_dev);
1144 static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[4], amd_dr_addr_mask);
1146 static unsigned int amd_msr_dr_addr_masks[] = {
1147 MSR_F16H_DR0_ADDR_MASK,
1148 MSR_F16H_DR1_ADDR_MASK,
1149 MSR_F16H_DR1_ADDR_MASK + 1,
1150 MSR_F16H_DR1_ADDR_MASK + 2
1153 void amd_set_dr_addr_mask(unsigned long mask, unsigned int dr)
1155 int cpu = smp_processor_id();
1157 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1160 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1163 if (per_cpu(amd_dr_addr_mask, cpu)[dr] == mask)
1166 wrmsr(amd_msr_dr_addr_masks[dr], mask, 0);
1167 per_cpu(amd_dr_addr_mask, cpu)[dr] = mask;
1170 unsigned long amd_get_dr_addr_mask(unsigned int dr)
1172 if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1175 if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1178 return per_cpu(amd_dr_addr_mask[dr], smp_processor_id());
1180 EXPORT_SYMBOL_GPL(amd_get_dr_addr_mask);
1182 u32 amd_get_highest_perf(void)
1184 struct cpuinfo_x86 *c = &boot_cpu_data;
1186 if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
1187 (c->x86_model >= 0x70 && c->x86_model < 0x80)))
1190 if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
1191 (c->x86_model >= 0x40 && c->x86_model < 0x70)))
1196 EXPORT_SYMBOL_GPL(amd_get_highest_perf);
1198 static void zenbleed_check_cpu(void *unused)
1200 struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
1202 zen2_zenbleed_check(c);
1205 void amd_check_microcode(void)
1207 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
1210 on_each_cpu(zenbleed_check_cpu, NULL, 1);
1214 * Issue a DIV 0/1 insn to clear any division data from previous DIV
1217 void noinstr amd_clear_divider(void)
1219 asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
1220 :: "a" (0), "d" (0), "r" (1));
1222 EXPORT_SYMBOL_GPL(amd_clear_divider);