diff options
Diffstat (limited to 'arch/x86/kernel/cpu/topology_amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/topology_amd.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/topology_amd.c b/arch/x86/kernel/cpu/topology_amd.c new file mode 100644 index 000000000000..1a8b3ad493af --- /dev/null +++ b/arch/x86/kernel/cpu/topology_amd.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/cpu.h> + +#include <asm/apic.h> +#include <asm/memtype.h> +#include <asm/processor.h> + +#include "cpu.h" + +static bool parse_8000_0008(struct topo_scan *tscan) +{ + struct { + // ecx + u32 cpu_nthreads : 8, // Number of physical threads - 1 + : 4, // Reserved + apicid_coreid_len : 4, // Number of thread core ID bits (shift) in APIC ID + perf_tsc_len : 2, // Performance time-stamp counter size + : 14; // Reserved + } ecx; + unsigned int sft; + + if (tscan->c->extended_cpuid_level < 0x80000008) + return false; + + cpuid_leaf_reg(0x80000008, CPUID_ECX, &ecx); + + /* If the thread bits are 0, then get the shift value from ecx.cpu_nthreads */ + sft = ecx.apicid_coreid_len; + if (!sft) + sft = get_count_order(ecx.cpu_nthreads + 1); + + topology_set_dom(tscan, TOPO_SMT_DOMAIN, sft, ecx.cpu_nthreads + 1); + return true; +} + +static void store_node(struct topo_scan *tscan, unsigned int nr_nodes, u16 node_id) +{ + /* + * Starting with Fam 17h the DIE domain could probably be used to + * retrieve the node info on AMD/HYGON. Analysis of CPUID dumps + * suggests it's the topmost bit(s) of the CPU cores area, but + * that's guess work and neither enumerated nor documented. + * + * Up to Fam 16h this does not work at all and the legacy node ID + * has to be used. + */ + tscan->amd_nodes_per_pkg = nr_nodes; + tscan->amd_node_id = node_id; +} + +static bool parse_8000_001e(struct topo_scan *tscan, bool has_0xb) +{ + struct { + // eax + u32 ext_apic_id : 32; // Extended APIC ID + // ebx + u32 core_id : 8, // Unique per-socket logical core unit ID + core_nthreads : 8, // #Threads per core (zero-based) + : 16; // Reserved + // ecx + u32 node_id : 8, // Node (die) ID of invoking logical CPU + nnodes_per_socket : 3, // #nodes in invoking logical CPU's package/socket + : 21; // Reserved + // edx + u32 : 32; // Reserved + } leaf; + + if (!boot_cpu_has(X86_FEATURE_TOPOEXT)) + return false; + + cpuid_leaf(0x8000001e, &leaf); + + tscan->c->topo.initial_apicid = leaf.ext_apic_id; + + /* + * If leaf 0xb is available, then SMT shift is set already. If not + * take it from ecx.threads_per_core and use topo_update_dom() - + * topology_set_dom() would propagate and overwrite the already + * propagated CORE level. + */ + if (!has_0xb) { + unsigned int nthreads = leaf.core_nthreads + 1; + + topology_update_dom(tscan, TOPO_SMT_DOMAIN, get_count_order(nthreads), nthreads); + } + + store_node(tscan, leaf.nnodes_per_socket + 1, leaf.node_id); + + if (tscan->c->x86_vendor == X86_VENDOR_AMD) { + if (tscan->c->x86 == 0x15) + tscan->c->topo.cu_id = leaf.core_id; + + cacheinfo_amd_init_llc_id(tscan->c, leaf.node_id); + } else { + /* + * Package ID is ApicId[6..] on certain Hygon CPUs. See + * commit e0ceeae708ce for explanation. The topology info + * is screwed up: The package shift is always 6 and the + * node ID is bit [4:5]. + */ + if (!boot_cpu_has(X86_FEATURE_HYPERVISOR) && tscan->c->x86_model <= 0x3) { + topology_set_dom(tscan, TOPO_CORE_DOMAIN, 6, + tscan->dom_ncpus[TOPO_CORE_DOMAIN]); + } + cacheinfo_hygon_init_llc_id(tscan->c); + } + return true; +} + +static bool parse_fam10h_node_id(struct topo_scan *tscan) +{ + struct { + union { + u64 node_id : 3, + nodes_per_pkg : 3, + unused : 58; + u64 msr; + }; + } nid; + + if (!boot_cpu_has(X86_FEATURE_NODEID_MSR)) + return false; + + rdmsrl(MSR_FAM10H_NODE_ID, nid.msr); + store_node(tscan, nid.nodes_per_pkg + 1, nid.node_id); + tscan->c->topo.llc_id = nid.node_id; + return true; +} + +static void legacy_set_llc(struct topo_scan *tscan) +{ + unsigned int apicid = tscan->c->topo.initial_apicid; + + /* parse_8000_0008() set everything up except llc_id */ + tscan->c->topo.llc_id = apicid >> tscan->dom_shifts[TOPO_CORE_DOMAIN]; +} + +static void parse_topology_amd(struct topo_scan *tscan) +{ + bool has_0xb = false; + + /* + * If the extended topology leaf 0x8000_001e is available + * try to get SMT and CORE shift from leaf 0xb first, then + * try to get the CORE shift from leaf 0x8000_0008. + */ + if (cpu_feature_enabled(X86_FEATURE_TOPOEXT)) + has_0xb = cpu_parse_topology_ext(tscan); + + if (!has_0xb && !parse_8000_0008(tscan)) + return; + + /* Prefer leaf 0x8000001e if available */ + if (parse_8000_001e(tscan, has_0xb)) + return; + + /* Try the NODEID MSR */ + if (parse_fam10h_node_id(tscan)) + return; + + legacy_set_llc(tscan); +} + +void cpu_parse_topology_amd(struct topo_scan *tscan) +{ + tscan->amd_nodes_per_pkg = 1; + parse_topology_amd(tscan); + + if (tscan->amd_nodes_per_pkg > 1) + set_cpu_cap(tscan->c, X86_FEATURE_AMD_DCM); +} + +void cpu_topology_fixup_amd(struct topo_scan *tscan) +{ + struct cpuinfo_x86 *c = tscan->c; + + /* + * Adjust the core_id relative to the node when there is more than + * one node. + */ + if (tscan->c->x86 < 0x17 && tscan->amd_nodes_per_pkg > 1) + c->topo.core_id %= tscan->dom_ncpus[TOPO_CORE_DOMAIN] / tscan->amd_nodes_per_pkg; +} |