v4.19.13 snapshot.
diff --git a/arch/powerpc/sysdev/of_rtc.c b/arch/powerpc/sysdev/of_rtc.c
new file mode 100644
index 0000000..153fdac
--- /dev/null
+++ b/arch/powerpc/sysdev/of_rtc.c
@@ -0,0 +1,61 @@
+/*
+ * Instantiate mmio-mapped RTC chips based on device tree information
+ *
+ * Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+
+static __initdata struct {
+ const char *compatible;
+ char *plat_name;
+} of_rtc_table[] = {
+ { "ds1743-nvram", "rtc-ds1742" },
+};
+
+void __init of_instantiate_rtc(void)
+{
+ struct device_node *node;
+ int err;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(of_rtc_table); i++) {
+ char *plat_name = of_rtc_table[i].plat_name;
+
+ for_each_compatible_node(node, NULL,
+ of_rtc_table[i].compatible) {
+ struct resource *res;
+
+ res = kmalloc(sizeof(*res), GFP_KERNEL);
+ if (!res) {
+ printk(KERN_ERR "OF RTC: Out of memory "
+ "allocating resource structure for %pOF\n",
+ node);
+ continue;
+ }
+
+ err = of_address_to_resource(node, 0, res);
+ if (err) {
+ printk(KERN_ERR "OF RTC: Error "
+ "translating resources for %pOF\n",
+ node);
+ continue;
+ }
+
+ printk(KERN_INFO "OF_RTC: %pOF is a %s @ 0x%llx-0x%llx\n",
+ node, plat_name,
+ (unsigned long long)res->start,
+ (unsigned long long)res->end);
+ platform_device_register_simple(plat_name, -1, res, 1);
+ }
+ }
+}