Initial pass-thru support for FAPI_PLAT_CALL_SUBROUTINE

Adding a transparent pass-thru for FAPI_PLAT_CALL_SUBROUTINE to
handle FAPI_CALL_SUBROUTINE calls from HWPs.  More work will be
required to convert these into chipops later.

Change-Id: Ib2e5cf018c681396b98e951d893f02cbe522ea53
RTC: 179062
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/45226
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

src/include/usr/fapi2/subroutine_executor.H

@@ -0,0 +1,58 @@
+/* IBM_PROLOG_BEGIN_TAG                                                   */
+/* This is an automatically generated prolog.                             */
+/*                                                                        */
+/* $Source: src/include/usr/fapi2/subroutine_executor.H $                 */
+/*                                                                        */
+/* OpenPOWER HostBoot Project                                             */
+/*                                                                        */
+/* Contributors Listed Below - COPYRIGHT 2016,2017                        */
+/* [+] International Business Machines Corp.                              */
+/*                                                                        */
+/*                                                                        */
+/* Licensed under the Apache License, Version 2.0 (the "License");        */
+/* you may not use this file except in compliance with the License.       */
+/* You may obtain a copy of the License at                                */
+/*                                                                        */
+/*     http://www.apache.org/licenses/LICENSE-2.0                         */
+/*                                                                        */
+/* Unless required by applicable law or agreed to in writing, software    */
+/* distributed under the License is distributed on an "AS IS" BASIS,      */
+/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or        */
+/* implied. See the License for the specific language governing           */
+/* permissions and limitations under the License.                         */
+/*                                                                        */
+/* IBM_PROLOG_END_TAG                                                     */
+///
+/// @file subroutine_executor.H
+///
+/// @brief Defines the PLAT Subroutine Executor Macro.
+///
+/// The PLAT Subroutine Executor macro is called by
+/// FAPI_CALL_SUBROUTINE when a hardware procedure has
+/// a subroutine is needed, typicaly a chipop function.
+///
+/// Example implementation of plat code
+
+#ifndef SUBROUTINEEXECUTOR_H_
+#define SUBROUTINEEXECUTOR_H_
+
+#include <fapi2_subroutine_executor.H>
+
+#include <plat_trace.H>
+
+/**
+ * @brief Subroutine Executor macro example code - Platforms will need to
+ *        implement as needed for their enviroment.
+ *
+ * This macro calls a PLAT macro which will do any platform specific work to
+ * execute the Subroutine (e.g. dlopening a shared library)
+ */
+#define FAPI_PLAT_CALL_SUBROUTINE(RC, FUNC, _args...) \
+    { \
+        FAPI_DBG("executing FAPI_PLAT_CALL_SUBROUTINE macro"); \
+        RC = FUNC(_args); \
+    }
+
+//@todo - RTC:179062 - Add real chipop support
+
+#endif