1 files changed, 220 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/topology_common.c b/arch/x86/kernel/cpu/topology_common.c
new file mode 100644
index 0000000000..9a6069e713
--- /dev/null
+++ b/arch/x86/kernel/cpu/topology_common.c
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <xen/xen.h>
+
+#include <asm/apic.h>
+#include <asm/processor.h>
+#include <asm/smp.h>
+
+#include "cpu.h"
+
+struct x86_topology_system x86_topo_system __ro_after_init;
+EXPORT_SYMBOL_GPL(x86_topo_system);
+
+unsigned int __amd_nodes_per_pkg __ro_after_init;
+EXPORT_SYMBOL_GPL(__amd_nodes_per_pkg);
+
+void topology_set_dom(struct topo_scan *tscan, enum x86_topology_domains dom,
+		      unsigned int shift, unsigned int ncpus)
+{
+	topology_update_dom(tscan, dom, shift, ncpus);
+
+	/* Propagate to the upper levels */
+	for (dom++; dom < TOPO_MAX_DOMAIN; dom++) {
+		tscan->dom_shifts[dom] = tscan->dom_shifts[dom - 1];
+		tscan->dom_ncpus[dom] = tscan->dom_ncpus[dom - 1];
+	}
+}
+
+static unsigned int __maybe_unused parse_num_cores_legacy(struct cpuinfo_x86 *c)
+{
+	struct {
+		u32	cache_type	:  5,
+			unused		: 21,
+			ncores		:  6;
+	} eax;
+
+	if (c->cpuid_level < 4)
+		return 1;
+
+	cpuid_subleaf_reg(4, 0, CPUID_EAX, &eax);
+	if (!eax.cache_type)
+		return 1;
+
+	return eax.ncores + 1;
+}
+
+static void parse_legacy(struct topo_scan *tscan)
+{
+	unsigned int cores, core_shift, smt_shift = 0;
+	struct cpuinfo_x86 *c = tscan->c;
+
+	cores = parse_num_cores_legacy(c);
+	core_shift = get_count_order(cores);
+
+	if (cpu_has(c, X86_FEATURE_HT)) {
+		if (!WARN_ON_ONCE(tscan->ebx1_nproc_shift < core_shift))
+			smt_shift = tscan->ebx1_nproc_shift - core_shift;
+		/*
+		 * The parser expects leaf 0xb/0x1f format, which means
+		 * the number of logical processors at core level is
+		 * counting threads.
+		 */
+		core_shift += smt_shift;
+		cores <<= smt_shift;
+	}
+
+	topology_set_dom(tscan, TOPO_SMT_DOMAIN, smt_shift, 1U << smt_shift);
+	topology_set_dom(tscan, TOPO_CORE_DOMAIN, core_shift, cores);
+}
+
+static bool fake_topology(struct topo_scan *tscan)
+{
+	/*
+	 * Preset the CORE level shift for CPUID less systems and XEN_PV,
+	 * which has useless CPUID information.
+	 */
+	topology_set_dom(tscan, TOPO_SMT_DOMAIN, 0, 1);
+	topology_set_dom(tscan, TOPO_CORE_DOMAIN, 0, 1);
+
+	return tscan->c->cpuid_level < 1;
+}
+
+static void parse_topology(struct topo_scan *tscan, bool early)
+{
+	const struct cpuinfo_topology topo_defaults = {
+		.cu_id			= 0xff,
+		.llc_id			= BAD_APICID,
+		.l2c_id			= BAD_APICID,
+	};
+	struct cpuinfo_x86 *c = tscan->c;
+	struct {
+		u32	unused0		: 16,
+			nproc		:  8,
+			apicid		:  8;
+	} ebx;
+
+	c->topo = topo_defaults;
+
+	if (fake_topology(tscan))
+		return;
+
+	/* Preset Initial APIC ID from CPUID leaf 1 */
+	cpuid_leaf_reg(1, CPUID_EBX, &ebx);
+	c->topo.initial_apicid = ebx.apicid;
+
+	/*
+	 * The initial invocation from early_identify_cpu() happens before
+	 * the APIC is mapped or X2APIC enabled. For establishing the
+	 * topology, that's not required. Use the initial APIC ID.
+	 */
+	if (early)
+		c->topo.apicid = c->topo.initial_apicid;
+	else
+		c->topo.apicid = read_apic_id();
+
+	/* The above is sufficient for UP */
+	if (!IS_ENABLED(CONFIG_SMP))
+		return;
+
+	tscan->ebx1_nproc_shift = get_count_order(ebx.nproc);
+
+	switch (c->x86_vendor) {
+	case X86_VENDOR_AMD:
+		if (IS_ENABLED(CONFIG_CPU_SUP_AMD))
+			cpu_parse_topology_amd(tscan);
+		break;
+	case X86_VENDOR_CENTAUR:
+	case X86_VENDOR_ZHAOXIN:
+		parse_legacy(tscan);
+		break;
+	case X86_VENDOR_INTEL:
+		if (!IS_ENABLED(CONFIG_CPU_SUP_INTEL) || !cpu_parse_topology_ext(tscan))
+			parse_legacy(tscan);
+		break;
+	case X86_VENDOR_HYGON:
+		if (IS_ENABLED(CONFIG_CPU_SUP_HYGON))
+			cpu_parse_topology_amd(tscan);
+		break;
+	}
+}
+
+static void topo_set_ids(struct topo_scan *tscan, bool early)
+{
+	struct cpuinfo_x86 *c = tscan->c;
+	u32 apicid = c->topo.apicid;
+
+	c->topo.pkg_id = topo_shift_apicid(apicid, TOPO_PKG_DOMAIN);
+	c->topo.die_id = topo_shift_apicid(apicid, TOPO_DIE_DOMAIN);
+
+	if (!early) {
+		c->topo.logical_pkg_id = topology_get_logical_id(apicid, TOPO_PKG_DOMAIN);
+		c->topo.logical_die_id = topology_get_logical_id(apicid, TOPO_DIE_DOMAIN);
+	}
+
+	/* Package relative core ID */
+	c->topo.core_id = (apicid & topo_domain_mask(TOPO_PKG_DOMAIN)) >>
+		x86_topo_system.dom_shifts[TOPO_SMT_DOMAIN];
+
+	c->topo.amd_node_id = tscan->amd_node_id;
+
+	if (c->x86_vendor == X86_VENDOR_AMD)
+		cpu_topology_fixup_amd(tscan);
+}
+
+void cpu_parse_topology(struct cpuinfo_x86 *c)
+{
+	unsigned int dom, cpu = smp_processor_id();
+	struct topo_scan tscan = { .c = c, };
+
+	parse_topology(&tscan, false);
+
+	if (IS_ENABLED(CONFIG_X86_LOCAL_APIC)) {
+		if (c->topo.initial_apicid != c->topo.apicid) {
+			pr_err(FW_BUG "CPU%4u: APIC ID mismatch. CPUID: 0x%04x APIC: 0x%04x\n",
+			       cpu, c->topo.initial_apicid, c->topo.apicid);
+		}
+
+		if (c->topo.apicid != cpuid_to_apicid[cpu]) {
+			pr_err(FW_BUG "CPU%4u: APIC ID mismatch. Firmware: 0x%04x APIC: 0x%04x\n",
+			       cpu, cpuid_to_apicid[cpu], c->topo.apicid);
+		}
+	}
+
+	for (dom = TOPO_SMT_DOMAIN; dom < TOPO_MAX_DOMAIN; dom++) {
+		if (tscan.dom_shifts[dom] == x86_topo_system.dom_shifts[dom])
+			continue;
+		pr_err(FW_BUG "CPU%d: Topology domain %u shift %u != %u\n", cpu, dom,
+		       tscan.dom_shifts[dom], x86_topo_system.dom_shifts[dom]);
+	}
+
+	topo_set_ids(&tscan, false);
+}
+
+void __init cpu_init_topology(struct cpuinfo_x86 *c)
+{
+	struct topo_scan tscan = { .c = c, };
+	unsigned int dom, sft;
+
+	parse_topology(&tscan, true);
+
+	/* Copy the shift values and calculate the unit sizes. */
+	memcpy(x86_topo_system.dom_shifts, tscan.dom_shifts, sizeof(x86_topo_system.dom_shifts));
+
+	dom = TOPO_SMT_DOMAIN;
+	x86_topo_system.dom_size[dom] = 1U << x86_topo_system.dom_shifts[dom];
+
+	for (dom++; dom < TOPO_MAX_DOMAIN; dom++) {
+		sft = x86_topo_system.dom_shifts[dom] - x86_topo_system.dom_shifts[dom - 1];
+		x86_topo_system.dom_size[dom] = 1U << sft;
+	}
+
+	topo_set_ids(&tscan, true);
+
+	/*
+	 * AMD systems have Nodes per package which cannot be mapped to
+	 * APIC ID.
+	 */
+	__amd_nodes_per_pkg = tscan.amd_nodes_per_pkg;
+}