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-rw-r--r--arch/arm64/kernel/Makefile2
-rw-r--r--arch/arm64/kernel/smp.c11
-rw-r--r--arch/arm64/kernel/topology.c95
3 files changed, 107 insertions, 1 deletions
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index e52bcdc6f097..cfee8273fccb 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -14,7 +14,7 @@ arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \
arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \
sys_compat.o
arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
-arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o
+arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o topology.o
arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o
arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o
arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 5070dc3b65d2..f0a141dd5655 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -114,6 +114,11 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
return ret;
}
+static void smp_store_cpu_info(unsigned int cpuid)
+{
+ store_cpu_topology(cpuid);
+}
+
/*
* This is the secondary CPU boot entry. We're using this CPUs
* idle thread stack, but a set of temporary page tables.
@@ -152,6 +157,8 @@ asmlinkage void secondary_start_kernel(void)
*/
notify_cpu_starting(cpu);
+ smp_store_cpu_info(cpu);
+
/*
* OK, now it's safe to let the boot CPU continue. Wait for
* the CPU migration code to notice that the CPU is online
@@ -391,6 +398,10 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
int err;
unsigned int cpu, ncores = num_possible_cpus();
+ init_cpu_topology();
+
+ smp_store_cpu_info(smp_processor_id());
+
/*
* are we trying to boot more cores than exist?
*/
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
new file mode 100644
index 000000000000..3e06b0be4ec8
--- /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);
+ }
+}