diff --git a/arch/mips/sgi-ip27/Makefile b/arch/mips/sgi-ip27/Makefile
index ab4affa..3283a30 100644
--- a/arch/mips/sgi-ip27/Makefile
+++ b/arch/mips/sgi-ip27/Makefile
@@ -9,3 +9,4 @@ obj-y	:= ip27-berr.o ip27-irq.o ip27-irqno.o ip27-init.o ip27-klconfig.o \
 obj-$(CONFIG_EARLY_PRINTK)	+= ip27-console.o
 obj-$(CONFIG_PCI)		+= ip27-irq-pci.o
 obj-$(CONFIG_SMP)		+= ip27-smp.o
+obj-$(CONFIG_RTC_DRV_M48T35)	+= ip27-rtc.o
diff --git a/arch/mips/sgi-ip27/ip27-rtc.c b/arch/mips/sgi-ip27/ip27-rtc.c
new file mode 100644
index 0000000..b14b026
--- /dev/null
+++ b/arch/mips/sgi-ip27/ip27-rtc.c
@@ -0,0 +1,143 @@
+/*
+ * 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.
+ *
+ * ip27-rtc.c: RTC submodule for IOC3 metadriver for IP27.
+ *
+ * Copyright (C) 2014 Joshua Kinard <kumba@gentoo.org>
+ *
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/rtc/m48t35.h>
+#include <linux/ioc3.h>
+
+#include <asm/addrspace.h>
+#include <asm/pci/bridge.h>
+#include <asm/sgi/ioc3.h>
+#include <asm/sn/klconfig.h>
+#include <asm/sn/arch.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/sn_private.h>
+#include <asm/sn/sn0/ip27.h>
+
+
+/*
+ * On IP27, the RTC is hidden behind the IOC3 device, attached to a generic
+ * ByteBus.  Use klconfig routines to safely map to the start address of the
+ * RTC area in ByteBus DEV0.
+ */
+#define IP27_RTC_RES_START (XPHYSADDR( \
+			    KL_CONFIG_CH_CONS_INFO(master_nasid)->memory_base \
+			    + IOC3_BYTEBUS_DEV0))
+#define IP27_RTC_RES_END (IP27_RTC_RES_START + 32767)
+
+static struct ioc3_driver_data *ioc3;
+static struct resource ip27_rtc_resources[1];
+static int ip27_rtc_probed = 0;
+
+/**
+ * ip27_rtc_read - read a value from an rtc register.
+ * @rtc: pointer to the m48t35 rtc structure.
+ * @reg: the register address to read.
+ */
+u8
+ip27_rtc_read(struct m48t35_priv *rtc, int reg)
+{
+	return readb(((u8 __iomem *)(((u64)(rtc->regs + reg)) ^ 3)));
+}
+
+/**
+ * ip27_rtc_write - write a value to an rtc register.
+ * @rtc: pointer to the m48t35 rtc structure.
+ * @reg: the register address to write.
+ * @value: value to write to the register.
+ */
+void
+ip27_rtc_write(struct m48t35_priv *rtc, int reg, u8 value)
+{
+	writeb(value, ((u8 __iomem *)(((u64)(rtc->regs + reg)) ^ 3)));
+}
+
+static struct m48t35_rtc_platform_data
+ip27_rtc_platform_data[] = {
+	{
+		/*
+		 * XXX: set req_mem_region to true after ioc3 resource
+		 * conflicts are resolved.
+		 */
+		.req_mem_region = false,
+		.plat_read = ip27_rtc_read,
+		.plat_write = ip27_rtc_write,
+	},
+};
+
+static struct platform_device
+ip27_rtc_device = {
+	.name = "rtc-m48t35",
+	.id = -1,
+	.dev = {
+		.platform_data = ip27_rtc_platform_data,
+	},
+	.num_resources = ARRAY_SIZE(ip27_rtc_resources),
+	.resource = ip27_rtc_resources,
+};
+
+
+/* IOC3 Metadriver probe/remove */
+static int
+ip27_ioc3_rtc_probe(struct ioc3_submodule *is, struct ioc3_driver_data *idd)
+{
+	int ret;
+
+	/* This code only applies to an Origin/Onyx2 */
+	if (ioc3 || (idd->class != IOC3_CLASS_BASE_IP27))
+		return 1;
+
+	ioc3 = idd;
+
+	if (ip27_rtc_probed)
+		return 0;
+
+	ip27_rtc_resources[0].start	= IP27_RTC_RES_START,
+	ip27_rtc_resources[0].end	= IP27_RTC_RES_END,
+	ip27_rtc_resources[0].flags	= IORESOURCE_MEM,
+
+	ret = platform_device_register(&ip27_rtc_device);
+	ip27_rtc_probed = 1;
+
+	return ret;
+}
+
+
+static int
+ip27_ioc3_rtc_remove(struct ioc3_submodule *is, struct ioc3_driver_data *idd)
+{
+	if (ioc3 != idd)
+		return 1;
+
+	platform_device_unregister(&ip27_rtc_device);
+	ioc3 = NULL;
+
+	return 0;
+}
+
+
+/* entry/exit functions */
+static struct ioc3_submodule
+ip27_ioc3_rtc_submodule = {
+	.name = "rtc",
+	.probe = ip27_ioc3_rtc_probe,
+	.remove = ip27_ioc3_rtc_remove,
+	.owner = THIS_MODULE,
+};
+
+ioc3_submodule_driver(ip27_ioc3_rtc_submodule);
+
+MODULE_AUTHOR("Joshua Kinard <kumba@gentoo.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("IP27 RTC Submodule for IOC3");
diff --git a/arch/mips/sgi-ip27/ip27-timer.c b/arch/mips/sgi-ip27/ip27-timer.c
index 42d6cb9..864db4f 100644
--- a/arch/mips/sgi-ip27/ip27-timer.c
+++ b/arch/mips/sgi-ip27/ip27-timer.c
@@ -213,23 +213,3 @@ void hub_rtc_init(cnodeid_t cnode)
 		LOCAL_HUB_S(PI_RT_PEND_B, 0);
 	}
 }
-
-static int __init sgi_ip27_rtc_devinit(void)
-{
-	struct resource res;
-
-	memset(&res, 0, sizeof(res));
-	res.start = XPHYSADDR(KL_CONFIG_CH_CONS_INFO(master_nasid)->memory_base +
-			      IOC3_BYTEBUS_DEV0);
-	res.end = res.start + 32767;
-	res.flags = IORESOURCE_MEM;
-
-	return IS_ERR(platform_device_register_simple("rtc-m48t35", -1,
-						      &res, 1));
-}
-
-/*
- * kludge make this a device_initcall after ioc3 resource conflicts
- * are resolved
- */
-late_initcall(sgi_ip27_rtc_devinit);