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authorPaul Moore <pmoore@redhat.com>2014-06-17 17:30:23 -0400
committerPaul Moore <pmoore@redhat.com>2014-06-17 17:30:23 -0400
commit170b5910d9fbea79de1bb40df22eda5f98250c0c (patch)
treeca9560e878d2842d45c6f99077d0d8b8f8b0f9ba /arch/arm64/kernel/topology.c
parent47dd0b76ace953bd2c0479076db0d3e3b9594003 (diff)
parent1860e379875dfe7271c649058aeddffe5afd9d0d (diff)
Merge tag 'v3.15' into next
Linux 3.15
Diffstat (limited to 'arch/arm64/kernel/topology.c')
-rw-r--r--arch/arm64/kernel/topology.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
new file mode 100644
index 00000000000..3e06b0be4ec
--- /dev/null
+++ b/arch/arm64/kernel/topology.c
@@ -0,0 +1,95 @@
+/*
+ * arch/arm64/kernel/topology.c
+ *
+ * Copyright (C) 2011,2013,2014 Linaro Limited.
+ *
+ * Based on the arm32 version written by Vincent Guittot in turn based on
+ * arch/sh/kernel/topology.c
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/percpu.h>
+#include <linux/node.h>
+#include <linux/nodemask.h>
+#include <linux/sched.h>
+
+#include <asm/topology.h>
+
+/*
+ * cpu topology table
+ */
+struct cpu_topology cpu_topology[NR_CPUS];
+EXPORT_SYMBOL_GPL(cpu_topology);
+
+const struct cpumask *cpu_coregroup_mask(int cpu)
+{
+ return &cpu_topology[cpu].core_sibling;
+}
+
+static void update_siblings_masks(unsigned int cpuid)
+{
+ struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
+ int cpu;
+
+ if (cpuid_topo->cluster_id == -1) {
+ /*
+ * DT does not contain topology information for this cpu
+ * reset it to default behaviour
+ */
+ pr_debug("CPU%u: No topology information configured\n", cpuid);
+ cpuid_topo->core_id = 0;
+ cpumask_set_cpu(cpuid, &cpuid_topo->core_sibling);
+ cpumask_set_cpu(cpuid, &cpuid_topo->thread_sibling);
+ return;
+ }
+
+ /* update core and thread sibling masks */
+ for_each_possible_cpu(cpu) {
+ cpu_topo = &cpu_topology[cpu];
+
+ if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
+ continue;
+
+ cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
+ if (cpu != cpuid)
+ cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
+
+ if (cpuid_topo->core_id != cpu_topo->core_id)
+ continue;
+
+ cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
+ if (cpu != cpuid)
+ cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
+ }
+}
+
+void store_cpu_topology(unsigned int cpuid)
+{
+ update_siblings_masks(cpuid);
+}
+
+/*
+ * init_cpu_topology is called at boot when only one cpu is running
+ * which prevent simultaneous write access to cpu_topology array
+ */
+void __init init_cpu_topology(void)
+{
+ unsigned int cpu;
+
+ /* init core mask and power*/
+ for_each_possible_cpu(cpu) {
+ struct cpu_topology *cpu_topo = &cpu_topology[cpu];
+
+ cpu_topo->thread_id = -1;
+ cpu_topo->core_id = -1;
+ cpu_topo->cluster_id = -1;
+ cpumask_clear(&cpu_topo->core_sibling);
+ cpumask_clear(&cpu_topo->thread_sibling);
+ }
+}