/* SPDX-License-Identifier: GPL-2.0-only */ #include <cpu/x86/lapic.h> #include <cpu/intel/common/common.h> #include <arch/cpu.h> #include <types.h> bool intel_ht_supported(void) { /* Is HyperThreading supported? */ return !!(cpuid_edx(1) & CPUID_FEAURE_HTT); } /* * Return true if running thread does not have the smallest lapic ID * within a CPU core. */ bool intel_ht_sibling(void) { struct cpuid_result result; unsigned int core_ids, apic_ids, threads; if (!intel_ht_supported()) return false; apic_ids = 1; if (cpuid_eax(0) >= 1) apic_ids = (cpuid_ebx(1) >> 16) & 0xff; if (apic_ids == 0) apic_ids = 1; core_ids = 1; if (cpuid_eax(0) >= 4) { result = cpuid_ext(4, 0); core_ids += (result.eax >> 26) & 0x3f; } threads = (apic_ids / core_ids); return !!(lapicid() & (threads - 1)); }