diff --git a/sys/dev/efidev/efidev.c b/sys/dev/efidev/efidev.c
--- a/sys/dev/efidev/efidev.c
+++ b/sys/dev/efidev/efidev.c
@@ -90,6 +90,21 @@
 		error = efi_set_time(tm);
 		break;
 	}
+	case EFIIOC_GET_WAKETIME:
+	{
+		struct efi_waketime_ioc *wt = (struct efi_waketime_ioc *)addr;
+
+		error = efi_get_waketime(&wt->enabled, &wt->pending,
+		    &wt->waketime);
+		break;
+	}
+	case EFIIOC_SET_WAKETIME:
+	{
+		struct efi_waketime_ioc *wt = (struct efi_waketime_ioc *)addr;
+
+		error = efi_set_waketime(wt->enabled, &wt->waketime);
+		break;
+	}
 	case EFIIOC_VAR_GET:
 	{
 		struct efi_var_ioc *ev = (struct efi_var_ioc *)addr;
diff --git a/sys/dev/efidev/efirt.c b/sys/dev/efidev/efirt.c
--- a/sys/dev/efidev/efirt.c
+++ b/sys/dev/efidev/efirt.c
@@ -32,6 +32,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_acpi.h"
+
 #include <sys/param.h>
 #include <sys/efi.h>
 #include <sys/eventhandler.h>
@@ -61,6 +63,10 @@
 #include <vm/pmap.h>
 #include <vm/vm_map.h>
 
+#ifdef DEV_ACPI
+#include <contrib/dev/acpica/include/acpi.h>
+#endif
+
 #define EFI_TABLE_ALLOC_MAX 0x800000
 
 static struct efi_systbl *efi_systbl;
@@ -571,6 +577,74 @@
 	return (error);
 }
 
+static int
+get_waketime(uint8_t *enabled, uint8_t *pending, struct efi_tm *tm)
+{
+	struct efirt_callinfo ec;
+	int error;
+#ifdef DEV_ACPI
+	UINT32 acpiRtcEnabled;
+#endif
+
+	if (efi_runtime == NULL)
+		return (ENXIO);
+
+	EFI_TIME_LOCK();
+	bzero(&ec, sizeof(ec));
+	ec.ec_name = "rt_getwaketime";
+	ec.ec_argcnt = 3;
+	ec.ec_arg1 = (uintptr_t)enabled;
+	ec.ec_arg2 = (uintptr_t)pending;
+	ec.ec_arg3 = (uintptr_t)tm;
+	ec.ec_fptr = EFI_RT_METHOD_PA(rt_getwaketime);
+	error = efi_call(&ec);
+	EFI_TIME_UNLOCK();
+
+#ifdef DEV_ACPI
+	if (error == 0) {
+		error = AcpiReadBitRegister(ACPI_BITREG_RT_CLOCK_ENABLE,
+		    &acpiRtcEnabled);
+		if (ACPI_SUCCESS(error)) {
+			*enabled = *enabled && acpiRtcEnabled;
+		} else
+			error = EIO;
+	}
+#endif
+
+	return (error);
+}
+
+static int
+set_waketime(uint8_t enable, struct efi_tm *tm)
+{
+	struct efirt_callinfo ec;
+	int error;
+
+	if (efi_runtime == NULL)
+		return (ENXIO);
+
+	EFI_TIME_LOCK();
+	bzero(&ec, sizeof(ec));
+	ec.ec_name = "rt_setwaketime";
+	ec.ec_argcnt = 2;
+	ec.ec_arg1 = (uintptr_t)enable;
+	ec.ec_arg2 = (uintptr_t)tm;
+	ec.ec_fptr = EFI_RT_METHOD_PA(rt_setwaketime);
+	error = efi_call(&ec);
+	EFI_TIME_UNLOCK();
+
+#ifdef DEV_ACPI
+	if (error == 0) {
+		error = AcpiWriteBitRegister(ACPI_BITREG_RT_CLOCK_ENABLE,
+		    (enable != 0) ? 1 : 0);
+		if (ACPI_FAILURE(error))
+			error = EIO;
+	}
+#endif
+
+	return (error);
+}
+
 static int
 get_time_capabilities(struct efi_tmcap *tmcap)
 {
@@ -713,6 +787,8 @@
 	.get_time_capabilities = get_time_capabilities,
 	.reset_system = reset_system,
 	.set_time = set_time,
+	.get_waketime = get_waketime,
+	.set_waketime = set_waketime,
 	.var_get = var_get,
 	.var_nextname = var_nextname,
 	.var_set = var_set,
diff --git a/sys/sys/efi.h b/sys/sys/efi.h
--- a/sys/sys/efi.h
+++ b/sys/sys/efi.h
@@ -254,6 +254,9 @@
 	int 	(*get_time_capabilities)(struct efi_tmcap *);
 	int	(*reset_system)(enum efi_reset);
 	int 	(*set_time)(struct efi_tm *);
+	int 	(*get_waketime)(uint8_t *enabled, uint8_t *pending,
+	    struct efi_tm *tm);
+	int 	(*set_waketime)(uint8_t enable, struct efi_tm *tm);
 	int 	(*var_get)(uint16_t *, struct uuid *, uint32_t *, size_t *,
     void *);
 	int 	(*var_nextname)(size_t *, uint16_t *, struct uuid *);
@@ -319,6 +322,21 @@
 	return (active_efi_ops->set_time(tm));
 }
 
+static inline int efi_get_waketime(uint8_t *enabled, uint8_t *pending,
+    struct efi_tm *tm)
+{
+	if (active_efi_ops->get_waketime == NULL)
+		return (ENXIO);
+	return (active_efi_ops->get_waketime(enabled, pending, tm));
+}
+
+static inline int efi_set_waketime(uint8_t enable, struct efi_tm *tm)
+{
+	if (active_efi_ops->set_waketime == NULL)
+		return (ENXIO);
+	return (active_efi_ops->set_waketime(enable, tm));
+}
+
 static inline int efi_var_get(uint16_t *name, struct uuid *vendor,
     uint32_t *attrib, size_t *datasize, void *data)
 {
diff --git a/sys/sys/efiio.h b/sys/sys/efiio.h
--- a/sys/sys/efiio.h
+++ b/sys/sys/efiio.h
@@ -50,11 +50,20 @@
 	size_t datasize;	/* Number of *bytes* in the data */
 };
 
+struct efi_waketime_ioc
+{
+	struct efi_tm	waketime;
+	uint8_t		enabled;
+	uint8_t		pending;
+};
+
 #define EFIIOC_GET_TABLE	_IOWR('E',  1, struct efi_get_table_ioc)
 #define EFIIOC_GET_TIME		_IOR('E',   2, struct efi_tm)
 #define EFIIOC_SET_TIME		_IOW('E',   3, struct efi_tm)
 #define EFIIOC_VAR_GET		_IOWR('E',  4, struct efi_var_ioc)
 #define EFIIOC_VAR_NEXT		_IOWR('E',  5, struct efi_var_ioc)
 #define EFIIOC_VAR_SET		_IOWR('E',  6, struct efi_var_ioc)
+#define EFIIOC_GET_WAKETIME	_IOR('E',   7, struct efi_waketime_ioc)
+#define EFIIOC_SET_WAKETIME	_IOW('E',   8, struct efi_waketime_ioc)
 
 #endif /* _SYS_EFIIO_H_ */