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-rw-r--r--arch/arm64/kernel/smp_spin_table.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c
new file mode 100644
index 000000000000..7c35fa682f76
--- /dev/null
+++ b/arch/arm64/kernel/smp_spin_table.c
@@ -0,0 +1,66 @@
+/*
+ * Spin Table SMP initialisation
+ *
+ * Copyright (C) 2013 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/smp.h>
+
+#include <asm/cacheflush.h>
+
+static phys_addr_t cpu_release_addr[NR_CPUS];
+
+static int __init smp_spin_table_init_cpu(struct device_node *dn, int cpu)
+{
+ /*
+ * Determine the address from which the CPU is polling.
+ */
+ if (of_property_read_u64(dn, "cpu-release-addr",
+ &cpu_release_addr[cpu])) {
+ pr_err("CPU %d: missing or invalid cpu-release-addr property\n",
+ cpu);
+
+ return -1;
+ }
+
+ return 0;
+}
+
+static int __init smp_spin_table_prepare_cpu(int cpu)
+{
+ void **release_addr;
+
+ if (!cpu_release_addr[cpu])
+ return -ENODEV;
+
+ release_addr = __va(cpu_release_addr[cpu]);
+ release_addr[0] = (void *)__pa(secondary_holding_pen);
+ __flush_dcache_area(release_addr, sizeof(release_addr[0]));
+
+ /*
+ * Send an event to wake up the secondary CPU.
+ */
+ sev();
+
+ return 0;
+}
+
+const struct smp_enable_ops smp_spin_table_ops __initconst = {
+ .name = "spin-table",
+ .init_cpu = smp_spin_table_init_cpu,
+ .prepare_cpu = smp_spin_table_prepare_cpu,
+};