Implement command GetDateTime

This commit implements the GetDateTime command which is
defined in PLDM Bios Control and Configuration Specification.

Change-Id: Iced21bbad7be07d357b6885b1b1e03b07a3da165
Signed-off-by: Sampa Misra <sampmisr@in.ibm.com>
diff --git a/libpldm/bios.h b/libpldm/bios.h
new file mode 100644
index 0000000..d173aeb
--- /dev/null
+++ b/libpldm/bios.h
@@ -0,0 +1,80 @@
+#ifndef BIOS_H
+#define BIOS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <asm/byteorder.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "base.h"
+
+/* Response lengths are inclusive of completion code */
+#define PLDM_GET_DATE_TIME_RESP_BYTES 8
+
+enum pldm_bios_commands { PLDM_GET_DATE_TIME = 0x0c };
+
+/* Requester */
+
+/* GetDateTime */
+
+/** @brief Create a PLDM request message for GetDateTime
+ *
+ *  @param[in] instance_id - Message's instance id
+ *  @param[out] msg - Message will be written to this
+ *  @return pldm_completion_codes
+ *  @note  Caller is responsible for memory alloc and dealloc of param
+ *         'msg.body.payload'
+ */
+
+int encode_get_date_time_req(uint8_t instance_id, struct pldm_msg *msg);
+
+/** @brief Decode a GetDateTime response message
+ *
+ *  @param[in] msg - Response message payload
+ *  @param[out] completion_code - Pointer to response msg's PLDM completion code
+ *  @param[out] seconds - Seconds in BCD format
+ *  @param[out] minutes - minutes in BCD format
+ *  @param[out] hours - hours in BCD format
+ *  @param[out] day - day of month in BCD format
+ *  @param[out] month - number of month in BCD format
+ *  @param[out] year - year in BCD format
+ *  @return pldm_completion_codes
+ */
+int decode_get_date_time_resp(const struct pldm_msg_payload *msg,
+			      uint8_t *completion_code, uint8_t *seconds,
+			      uint8_t *minutes, uint8_t *hours, uint8_t *day,
+			      uint8_t *month, uint16_t *year);
+
+/* Responder */
+
+/* GetDateTime */
+
+/** @brief Create a PLDM response message for GetDateTime
+ *
+ *  @param[in] instance_id - Message's instance id
+ *  @param[in] completion_code - PLDM completion code
+ *  @param[in] seconds - seconds in BCD format
+ *  @param[in] minutes - minutes in BCD format
+ *  @param[in] hours - hours in BCD format
+ *  @param[in] day - day of the month in BCD format
+ *  @param[in] month - number of month in BCD format
+ *  @param[in] year - year in BCD format
+ *  @param[out] msg - Message will be written to this
+ *  @return pldm_completion_codes
+ *  @note  Caller is responsible for memory alloc and dealloc of param
+ *         'msg.body.payload'
+ */
+
+int encode_get_date_time_resp(uint8_t instance_id, uint8_t completion_code,
+			      uint8_t seconds, uint8_t minutes, uint8_t hours,
+			      uint8_t day, uint8_t month, uint16_t year,
+			      struct pldm_msg *msg);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* BIOS_H */