1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 22decb194SH. Peter Anvin /* 32decb194SH. Peter Anvin * Check for extended topology enumeration cpuid leaf 0xb and if it 42decb194SH. Peter Anvin * exists, use it for populating initial_apicid and cpu topology 52decb194SH. Peter Anvin * detection. 62decb194SH. Peter Anvin */ 72decb194SH. Peter Anvin 82decb194SH. Peter Anvin #include <linux/cpu.h> 92decb194SH. Peter Anvin #include <asm/apic.h> 102decb194SH. Peter Anvin #include <asm/pat.h> 112decb194SH. Peter Anvin #include <asm/processor.h> 122decb194SH. Peter Anvin 132decb194SH. Peter Anvin /* leaf 0xb SMT level */ 142decb194SH. Peter Anvin #define SMT_LEVEL 0 152decb194SH. Peter Anvin 162decb194SH. Peter Anvin /* leaf 0xb sub-leaf types */ 172decb194SH. Peter Anvin #define INVALID_TYPE 0 182decb194SH. Peter Anvin #define SMT_TYPE 1 192decb194SH. Peter Anvin #define CORE_TYPE 2 202decb194SH. Peter Anvin 212decb194SH. Peter Anvin #define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff) 222decb194SH. Peter Anvin #define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f) 232decb194SH. Peter Anvin #define LEVEL_MAX_SIBLINGS(ebx) ((ebx) & 0xffff) 242decb194SH. Peter Anvin 252decb194SH. Peter Anvin /* 262decb194SH. Peter Anvin * Check for extended topology enumeration cpuid leaf 0xb and if it 272decb194SH. Peter Anvin * exists, use it for populating initial_apicid and cpu topology 282decb194SH. Peter Anvin * detection. 292decb194SH. Peter Anvin */ 306c4f5abaSSuravee Suthikulpanit int detect_extended_topology(struct cpuinfo_x86 *c) 312decb194SH. Peter Anvin { 322decb194SH. Peter Anvin #ifdef CONFIG_SMP 332decb194SH. Peter Anvin unsigned int eax, ebx, ecx, edx, sub_index; 342decb194SH. Peter Anvin unsigned int ht_mask_width, core_plus_mask_width; 352decb194SH. Peter Anvin unsigned int core_select_mask, core_level_siblings; 362decb194SH. Peter Anvin static bool printed; 372decb194SH. Peter Anvin 382decb194SH. Peter Anvin if (c->cpuid_level < 0xb) 396c4f5abaSSuravee Suthikulpanit return -1; 402decb194SH. Peter Anvin 412decb194SH. Peter Anvin cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx); 422decb194SH. Peter Anvin 432decb194SH. Peter Anvin /* 442decb194SH. Peter Anvin * check if the cpuid leaf 0xb is actually implemented. 452decb194SH. Peter Anvin */ 462decb194SH. Peter Anvin if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE)) 476c4f5abaSSuravee Suthikulpanit return -1; 482decb194SH. Peter Anvin 492decb194SH. Peter Anvin set_cpu_cap(c, X86_FEATURE_XTOPOLOGY); 502decb194SH. Peter Anvin 512decb194SH. Peter Anvin /* 522decb194SH. Peter Anvin * initial apic id, which also represents 32-bit extended x2apic id. 532decb194SH. Peter Anvin */ 542decb194SH. Peter Anvin c->initial_apicid = edx; 552decb194SH. Peter Anvin 562decb194SH. Peter Anvin /* 572decb194SH. Peter Anvin * Populate HT related information from sub-leaf level 0. 582decb194SH. Peter Anvin */ 592decb194SH. Peter Anvin core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx); 602decb194SH. Peter Anvin core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); 612decb194SH. Peter Anvin 622decb194SH. Peter Anvin sub_index = 1; 632decb194SH. Peter Anvin do { 642decb194SH. Peter Anvin cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx); 652decb194SH. Peter Anvin 662decb194SH. Peter Anvin /* 672decb194SH. Peter Anvin * Check for the Core type in the implemented sub leaves. 682decb194SH. Peter Anvin */ 692decb194SH. Peter Anvin if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) { 702decb194SH. Peter Anvin core_level_siblings = LEVEL_MAX_SIBLINGS(ebx); 712decb194SH. Peter Anvin core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); 722decb194SH. Peter Anvin break; 732decb194SH. Peter Anvin } 742decb194SH. Peter Anvin 752decb194SH. Peter Anvin sub_index++; 762decb194SH. Peter Anvin } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE); 772decb194SH. Peter Anvin 782decb194SH. Peter Anvin core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width; 792decb194SH. Peter Anvin 802decb194SH. Peter Anvin c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width) 812decb194SH. Peter Anvin & core_select_mask; 822decb194SH. Peter Anvin c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width); 832decb194SH. Peter Anvin /* 842decb194SH. Peter Anvin * Reinit the apicid, now that we have extended initial_apicid. 852decb194SH. Peter Anvin */ 862decb194SH. Peter Anvin c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); 872decb194SH. Peter Anvin 882decb194SH. Peter Anvin c->x86_max_cores = (core_level_siblings / smp_num_siblings); 892decb194SH. Peter Anvin 902decb194SH. Peter Anvin if (!printed) { 911b74dde7SChen Yucong pr_info("CPU: Physical Processor ID: %d\n", 922decb194SH. Peter Anvin c->phys_proc_id); 932decb194SH. Peter Anvin if (c->x86_max_cores > 1) 941b74dde7SChen Yucong pr_info("CPU: Processor Core ID: %d\n", 952decb194SH. Peter Anvin c->cpu_core_id); 962decb194SH. Peter Anvin printed = 1; 972decb194SH. Peter Anvin } 982decb194SH. Peter Anvin #endif 996c4f5abaSSuravee Suthikulpanit return 0; 1002decb194SH. Peter Anvin } 101