diff --git a/arch/arm/include/asm/arch-apple/rtkit.h b/arch/arm/include/asm/arch-apple/rtkit.h
index 51f77f2..eff18dd 100644
--- a/arch/arm/include/asm/arch-apple/rtkit.h
+++ b/arch/arm/include/asm/arch-apple/rtkit.h
@@ -7,5 +7,23 @@
 #define APPLE_RTKIT_PWR_STATE_QUIESCED	0x10
 #define APPLE_RTKIT_PWR_STATE_ON	0x20
 
-int apple_rtkit_init(struct mbox_chan *);
-int apple_rtkit_shutdown(struct mbox_chan *, int);
+struct apple_rtkit_buffer {
+	void *buffer;
+	u64 dva;
+	size_t size;
+	bool is_mapped;
+};
+
+typedef int (*apple_rtkit_shmem_setup)(void *cookie,
+				       struct apple_rtkit_buffer *buf);
+typedef void (*apple_rtkit_shmem_destroy)(void *cookie,
+					  struct apple_rtkit_buffer *buf);
+
+struct apple_rtkit;
+
+struct apple_rtkit *apple_rtkit_init(struct mbox_chan *chan, void *cookie,
+				     apple_rtkit_shmem_setup shmem_setup,
+				     apple_rtkit_shmem_destroy shmem_destroy);
+void apple_rtkit_free(struct apple_rtkit *rtk);
+int apple_rtkit_boot(struct apple_rtkit *rtk);
+int apple_rtkit_shutdown(struct apple_rtkit *rtk, int pwrstate);
diff --git a/arch/arm/include/asm/arch-apple/sart.h b/arch/arm/include/asm/arch-apple/sart.h
new file mode 100644
index 0000000..b99bdea
--- /dev/null
+++ b/arch/arm/include/asm/arch-apple/sart.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * The sart code is copied from m1n1 (https://github.com/AsahiLinux/m1n1) and
+ * licensed as MIT.
+ *
+ * (C) Copyright 2022 The Asahi Linux Contributors
+ */
+
+#ifndef SART_H
+#define SART_H
+
+#include <dm/ofnode.h>
+
+struct apple_sart;
+
+struct apple_sart *sart_init(ofnode node);
+void sart_free(struct apple_sart *sart);
+
+bool sart_add_allowed_region(struct apple_sart *sart, void *paddr, size_t sz);
+bool sart_remove_allowed_region(struct apple_sart *sart, void *paddr, size_t sz);
+
+#endif