arm64: SMP: enable PSCI boot method

Wire the PSCI implementation into the SMP secondary startup
code.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/smp.h

@@ -75,5 +75,6 @@ struct smp_enable_ops {
 };
 
 extern const struct smp_enable_ops smp_spin_table_ops;
+extern const struct smp_enable_ops smp_psci_ops;
 
 #endif /* ifndef __ASM_SMP_H */

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 smp_psci.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

arch/arm64/kernel/smp.c

@@ -236,6 +236,7 @@ static void (*smp_cross_call)(const struct cpumask *, unsigned int);
 
 static const struct smp_enable_ops *enable_ops[] __initconst = {
 	&smp_spin_table_ops,
+	&smp_psci_ops,
 	NULL,
 };
 

arch/arm64/kernel/smp_psci.c

@@ -0,0 +1,52 @@
+/*
+ * PSCI 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/psci.h>
+
+static int __init smp_psci_init_cpu(struct device_node *dn, int cpu)
+{
+	return 0;
+}
+
+static int __init smp_psci_prepare_cpu(int cpu)
+{
+	int err;
+
+	if (!psci_ops.cpu_on) {
+		pr_err("psci: no cpu_on method, not booting CPU%d\n", cpu);
+		return -ENODEV;
+	}
+
+	err = psci_ops.cpu_on(cpu, __pa(secondary_holding_pen));
+	if (err) {
+		pr_err("psci: failed to boot CPU%d (%d)\n", cpu, err);
+		return err;
+	}
+
+	return 0;
+}
+
+const struct smp_enable_ops smp_psci_ops __initconst = {
+	.name		= "psci",
+	.init_cpu 	= smp_psci_init_cpu,
+	.prepare_cpu	= smp_psci_prepare_cpu,
+};