drm/amd/powerplay: add a common pp endian header

To replace the duplicated versions of this in all asic
variants.
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Ken Wang <Qingqing.Wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/powerplay/inc/pp_endian.h

+/*
+ * Copyright 2016 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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 _PP_ENDIAN_H_
+#define _PP_ENDIAN_H_
+
+#define PP_HOST_TO_SMC_UL(X) cpu_to_be32(X)
+#define PP_SMC_TO_HOST_UL(X) be32_to_cpu(X)
+
+#define PP_HOST_TO_SMC_US(X) cpu_to_be16(X)
+#define PP_SMC_TO_HOST_US(X) be16_to_cpu(X)
+
+#define CONVERT_FROM_HOST_TO_SMC_UL(X) ((X) = PP_HOST_TO_SMC_UL(X))
+#define CONVERT_FROM_SMC_TO_HOST_UL(X) ((X) = PP_SMC_TO_HOST_UL(X))
+
+#define CONVERT_FROM_HOST_TO_SMC_US(X) ((X) = PP_HOST_TO_SMC_US(X))
+
+#endif /* _PP_ENDIAN_H_ */