diff options
Diffstat (limited to 'arch/x86/kernel/cpu/topology_amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/topology_amd.c | 48 |
1 files changed, 28 insertions, 20 deletions
diff --git a/arch/x86/kernel/cpu/topology_amd.c b/arch/x86/kernel/cpu/topology_amd.c index 843b1655ab45..c79ebbb639cb 100644 --- a/arch/x86/kernel/cpu/topology_amd.c +++ b/arch/x86/kernel/cpu/topology_amd.c @@ -81,20 +81,25 @@ static bool parse_8000_001e(struct topo_scan *tscan, bool has_topoext) cpuid_leaf(0x8000001e, &leaf); - tscan->c->topo.initial_apicid = leaf.ext_apic_id; - /* - * If leaf 0xb is available, then the domain shifts are set - * already and nothing to do here. Only valid for family >= 0x17. + * If leaf 0xb/0x26 is available, then the APIC ID and the domain + * shifts are set already. */ - if (!has_topoext && tscan->c->x86 >= 0x17) { + if (!has_topoext) { + tscan->c->topo.initial_apicid = leaf.ext_apic_id; + /* - * Leaf 0x80000008 set the CORE domain shift already. - * Update the SMT domain, but do not propagate it. + * Leaf 0x8000008 sets the CORE domain shift but not the + * SMT domain shift. On CPUs with family >= 0x17, there + * might be hyperthreads. */ - unsigned int nthreads = leaf.core_nthreads + 1; + if (tscan->c->x86 >= 0x17) { + /* Update the SMT domain, but do not propagate it. */ + unsigned int nthreads = leaf.core_nthreads + 1; - topology_update_dom(tscan, TOPO_SMT_DOMAIN, get_count_order(nthreads), nthreads); + topology_update_dom(tscan, TOPO_SMT_DOMAIN, + get_count_order(nthreads), nthreads); + } } store_node(tscan, leaf.nnodes_per_socket + 1, leaf.node_id); @@ -170,27 +175,30 @@ static void topoext_fixup(struct topo_scan *tscan) static void parse_topology_amd(struct topo_scan *tscan) { - bool has_topoext = false; - /* - * If the extended topology leaf 0x8000_001e is available - * try to get SMT, CORE, TILE, and DIE shifts from extended + * Try to get SMT, CORE, TILE, and DIE shifts from extended * CPUID leaf 0x8000_0026 on supported processors first. If * extended CPUID leaf 0x8000_0026 is not supported, try to - * get SMT and CORE shift from leaf 0xb first, then try to - * get the CORE shift from leaf 0x8000_0008. + * get SMT and CORE shift from leaf 0xb. If either leaf is + * available, cpu_parse_topology_ext() will return true. */ - if (cpu_feature_enabled(X86_FEATURE_TOPOEXT)) - has_topoext = cpu_parse_topology_ext(tscan); + bool has_xtopology = cpu_parse_topology_ext(tscan); if (cpu_feature_enabled(X86_FEATURE_AMD_HTR_CORES)) tscan->c->topo.cpu_type = cpuid_ebx(0x80000026); - if (!has_topoext && !parse_8000_0008(tscan)) + /* + * If XTOPOLOGY leaves (0x26/0xb) are not available, try to + * get the CORE shift from leaf 0x8000_0008 first. + */ + if (!has_xtopology && !parse_8000_0008(tscan)) return; - /* Prefer leaf 0x8000001e if available */ - if (parse_8000_001e(tscan, has_topoext)) + /* + * Prefer leaf 0x8000001e if available to get the SMT shift and + * the initial APIC ID if XTOPOLOGY leaves are not available. + */ + if (parse_8000_001e(tscan, has_xtopology)) return; /* Try the NODEID MSR */ |