Revert "hikey960: Remove hifi dsp support."

This reverts commit 1d7e5889cd761a9eaecb130c52582d2b0707a08d.

Reason for revert: previous commit broke build_test target, b/219798815

Change-Id: If678459053b79b81de27a1b7d514cc0c6101d97d
diff --git a/hifi/xaf/host-apf/include/xf-proto.h b/hifi/xaf/host-apf/include/xf-proto.h
new file mode 100644
index 0000000..095e353
--- /dev/null
+++ b/hifi/xaf/host-apf/include/xf-proto.h
@@ -0,0 +1,82 @@
+/*******************************************************************************
+* Copyright (C) 2018 Cadence Design Systems, Inc.
+* 
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to use this Software with Cadence processor cores only and 
+* not with any other processors and platforms, subject to
+* the following conditions:
+* 
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+* 
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+******************************************************************************/
+
+#ifndef __XF_H
+#error "xf-proto.h mustn't be included directly"
+#endif
+
+/*******************************************************************************
+ * Forward types declarations
+ ******************************************************************************/
+
+/* ...component string identifier */
+typedef const char             *xf_id_t;
+
+/* ...handle to proxy data */
+typedef struct xf_proxy         xf_proxy_t;
+
+/* ...handle to component data */
+typedef struct xf_handle        xf_handle_t;
+
+/* ...buffer pool */
+typedef struct xf_pool          xf_pool_t;
+
+/* ...individual buffer from pool */
+typedef struct xf_buffer        xf_buffer_t;
+
+/* ...buffer pool type */
+typedef u32                     xf_pool_type_t;
+
+/* ...user-message */
+typedef struct xf_user_msg      xf_user_msg_t;
+
+/* ...proxy-message */
+typedef struct xf_proxy_msg     xf_proxy_msg_t;
+
+/* ...response callback */
+typedef void (*xf_response_cb)(xf_handle_t *h, xf_user_msg_t *msg);
+
+typedef void* xaf_mem_malloc_fxn_t(s32 size, s32 id);
+typedef void  xaf_mem_free_fxn_t(void* ptr, s32 id);
+
+/*******************************************************************************
+ * High-level API functions
+ ******************************************************************************/
+
+/* ...component operations */
+extern int      xf_open(xf_proxy_t *proxy, xf_handle_t *handle, xf_id_t id, u32 core, xf_response_cb cb);
+extern void     xf_close(xf_handle_t *handle);
+extern int      xf_command(xf_handle_t *handle, u32 dst, u32 opcode, void *buf, u32 length);
+extern int      xf_route(xf_handle_t *src, u32 s_port, xf_handle_t *dst, u32 d_port, u32 num, u32 size, u32 align);
+extern int      xf_unroute(xf_handle_t *src, u32 s_port);
+
+/* ...shared buffers operations */
+extern int      xf_pool_alloc(xf_proxy_t *proxy, u32 number, u32 length, xf_pool_type_t type, xf_pool_t **pool, s32 id, 
+		xaf_mem_malloc_fxn_t, xaf_mem_free_fxn_t);
+extern void     xf_pool_free(xf_pool_t *pool, s32 id, xaf_mem_free_fxn_t);
+extern xf_buffer_t * xf_buffer_get(xf_pool_t *pool);
+extern void     xf_buffer_put(xf_buffer_t *buffer);
+
+/* ...proxy operations */
+extern int      xf_proxy_init(xf_proxy_t *proxy, u32 core, void *p_shmem);
+extern void     xf_proxy_close(xf_proxy_t *proxy);
+