1 files changed, 44 insertions, 28 deletions

diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c
index fb8ff9ba467a..5ea337dd2f15 100644
--- a/arch/arm64/kernel/cpu_ops.c
+++ b/arch/arm64/kernel/cpu_ops.c
@@ -16,11 +16,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <asm/cpu_ops.h>
-#include <asm/smp_plat.h>
+#include <linux/acpi.h>
 #include <linux/errno.h>
 #include <linux/of.h>
 #include <linux/string.h>
+#include <asm/acpi.h>
+#include <asm/cpu_ops.h>
+#include <asm/smp_plat.h>
 
 extern const struct cpu_operations smp_spin_table_ops;
 extern const struct cpu_operations cpu_psci_ops;
@@ -35,7 +37,7 @@ static const struct cpu_operations *supported_cpu_ops[] __initconst = {
 	NULL,
 };
 
-const struct cpu_operations * __init cpu_get_ops(const char *name)
+static const struct cpu_operations * __init cpu_get_ops(const char *name)
 {
 	const struct cpu_operations **ops = supported_cpu_ops;
 
@@ -49,39 +51,53 @@ const struct cpu_operations * __init cpu_get_ops(const char *name)
 	return NULL;
 }
 
+static const char *__init cpu_read_enable_method(int cpu)
+{
+	const char *enable_method;
+
+	if (acpi_disabled) {
+		struct device_node *dn = of_get_cpu_node(cpu, NULL);
+
+		if (!dn) {
+			if (!cpu)
+				pr_err("Failed to find device node for boot cpu\n");
+			return NULL;
+		}
+
+		enable_method = of_get_property(dn, "enable-method", NULL);
+		if (!enable_method) {
+			/*
+			 * The boot CPU may not have an enable method (e.g.
+			 * when spin-table is used for secondaries).
+			 * Don't warn spuriously.
+			 */
+			if (cpu != 0)
+				pr_err("%s: missing enable-method property\n",
+					dn->full_name);
+		}
+	} else {
+		enable_method = acpi_get_enable_method(cpu);
+		if (!enable_method)
+			pr_err("Unsupported ACPI enable-method\n");
+	}
+
+	return enable_method;
+}
 /*
- * Read a cpu's enable method from the device tree and record it in cpu_ops.
+ * Read a cpu's enable method and record it in cpu_ops.
  */
-int __init cpu_read_ops(struct device_node *dn, int cpu)
+int __init cpu_read_ops(int cpu)
 {
-	const char *enable_method = of_get_property(dn, "enable-method", NULL);
-	if (!enable_method) {
-		/*
-		 * The boot CPU may not have an enable method (e.g. when
-		 * spin-table is used for secondaries). Don't warn spuriously.
-		 */
-		if (cpu != 0)
-			pr_err("%s: missing enable-method property\n",
-				dn->full_name);
-		return -ENOENT;
-	}
+	const char *enable_method = cpu_read_enable_method(cpu);
+
+	if (!enable_method)
+		return -ENODEV;
 
 	cpu_ops[cpu] = cpu_get_ops(enable_method);
 	if (!cpu_ops[cpu]) {
-		pr_warn("%s: unsupported enable-method property: %s\n",
-			dn->full_name, enable_method);
+		pr_warn("Unsupported enable-method: %s\n", enable_method);
 		return -EOPNOTSUPP;
 	}
 
 	return 0;
 }
-
-void __init cpu_read_bootcpu_ops(void)
-{
-	struct device_node *dn = of_get_cpu_node(0, NULL);
-	if (!dn) {
-		pr_err("Failed to find device node for boot cpu\n");
-		return;
-	}
-	cpu_read_ops(dn, 0);
-}