Interface: Interface provided to NS side

These files provide a reference interface mplementation for integration
with OS running on the NS side. This has been tested to work with
RTX scheduler.
Modifications may be required while integrating other OS.

Change-Id: I4845584465c5df0bc574de31564a0789154c0dd5
Signed-off-by: Ashutosh Singh <ashutosh.singh@arm.com>
Co-Authored-By: Marc Moreno Berengue <marc.morenoberengue@arm.com>
Co-Authored-By: Antonio de Angelis <antonio.deangelis@arm.com>
diff --git a/interface/include/tfm_sst_api.h b/interface/include/tfm_sst_api.h
new file mode 100644
index 0000000..3cdb64e
--- /dev/null
+++ b/interface/include/tfm_sst_api.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2017, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef __TFM_SST_API__
+#define __TFM_SST_API__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief Gets handler for the given asset UUID. If an asset is deleted, the
+ *        linked asset handle reference is no longer valid and will give
+ *        TFM_SST_ERR_ASSET_REF_INVALID if used.
+ *
+ * \param[in]  asset_uuid  Asset UUID
+ * \param[out] hdl         Pointer to store the asset's handler
+ *
+ * \return Returns TFM_SST_ERR_SUCCESS if asset is found. Otherwise, error code
+ *         as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t tfm_sst_get_handle(uint16_t asset_uuid,
+                                      uint32_t* hdl);
+
+/**
+ * \brief Allocates space for the asset, referenced by asset handler,
+ *        without setting any data in the asset.
+ *
+ * \param[in] asset_uuid  Asset UUID
+ *
+ * \return Returns an TFM_SST_ERR_SUCCESS if asset is created correctly.
+ *         Otherwise, error code as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t  tfm_sst_create(uint16_t asset_uuid);
+
+/**
+ * \brief Gets asset's attributes referenced by asset handler.
+ *        Uses cached metadata to return the size and write offset of an asset.
+ *
+ * \param[in]  asset_handle   Asset handler
+ * \param[out] attrib_struct  Pointer to store the asset's attribute
+ *
+ * \return Returns error code as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t tfm_sst_get_attributes(uint32_t asset_handle,
+                                          struct tfm_sst_attribs_t* attrib_struct);
+
+/**
+ * \brief Reads asset's data from asset referenced by asset handler.
+ *
+ * \param[in]  asset_handle   Asset handler
+ * \param[out] data           Pointer to data vector \ref tfm_sst_buf_t to store
+ *                            data, size and offset
+ *
+ * \return Returns error code as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t tfm_sst_read(uint32_t asset_handle,
+                                struct tfm_sst_buf_t* data);
+
+/**
+ * \brief Writes data into an asset referenced by asset handler.
+ *
+ * \param[in] asset_handle   Asset handler
+ * \param[in] data           Pointer to data vector \ref tfm_sst_buf_t which
+ *                           contains the data to write
+ *
+ * \return Returns error code as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t tfm_sst_write(uint32_t asset_handle,
+                                 struct tfm_sst_buf_t* data);
+
+/**
+ * \brief Deletes the asset referenced by the asset handler.
+ *
+ * \param[in] asset_handle  Asset handler
+ *
+ * \return Returns error code as specified in \ref tfm_sst_err_t
+ */
+enum tfm_sst_err_t tfm_sst_delete(uint32_t asset_handle);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __TFM_SST_API__ */