diff --git a/spm/common/sp_def.h b/spm/common/sp_def.h
new file mode 100644
index 0000000..2b26b68
--- /dev/null
+++ b/spm/common/sp_def.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SP_DEF_H
+#define SP_DEF_H
+
+#include <utils_def.h>
+#include <sp_platform_def.h>
+
+/*
+ * Layout of the Secure Partition image.
+ */
+
+/* Up to 2 MiB at an arbitrary address that doesn't overlap the devices. */
+#define SP_IMAGE_BASE		ULL(0x1000)
+#define SP_IMAGE_SIZE		ULL(0x200000)
+
+/* Memory reserved for stacks */
+#define SP_STACKS_SIZE		ULL(0x1000)
+
+/*
+ * RX/TX buffer used by VM's in SPM for memory sharing
+ * Each VM allocated 2 pages, one for RX and one for TX buffer.
+ */
+#define SP_RX_BASE			PLAT_SP_RX_BASE
+#define SP_TX_BASE			SP_RX_BASE + PAGE_SIZE
+#define SP_RX_TX_SIZE			PAGE_SIZE * 2
+
+/*
+ * RX/TX buffer helpers.
+ */
+#define get_sp_rx_start(sp_id) (SP_RX_BASE \
+				+ (((sp_id & 0x7FFFU) - 1U) * SP_RX_TX_SIZE))
+#define get_sp_rx_end(sp_id) (SP_RX_BASE \
+			      + (((sp_id & 0x7FFFU) - 1U) * SP_RX_TX_SIZE) \
+			      + PAGE_SIZE)
+#define get_sp_tx_start(sp_id) (SP_TX_BASE + \
+				(((sp_id & 0x7FFFU) - 1U) * SP_RX_TX_SIZE))
+#define get_sp_tx_end(sp_id) (SP_TX_BASE \
+			      + (((sp_id & 0x7FFFU) - 1U) * SP_RX_TX_SIZE) \
+			      + PAGE_SIZE)
+
+#endif /* SP_DEF_H */