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diff --git a/include/rtems/score/mrsp.h b/include/rtems/score/mrsp.h
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+/*
+ * Copyright (c) 2014 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef _RTEMS_SCORE_MRSP_H
+#define _RTEMS_SCORE_MRSP_H
+
+#include <rtems/score/cpuopts.h>
+
+#if defined(RTEMS_SMP)
+
+#include <rtems/score/chain.h>
+#include <rtems/score/isrlock.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/thread.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup ScoreMRSP Multiprocessor Resource Sharing Protocol Handler
+ *
+ * @ingroup Score
+ *
+ * @brief Multiprocessor Resource Sharing Protocol (MrsP).
+ *
+ * The Multiprocessor Resource Sharing Protocol (MrsP) is defined in A.  Burns
+ * and A.J.  Wellings, A Schedulability Compatible Multiprocessor Resource
+ * Sharing Protocol - MrsP, Proceedings of the 25th Euromicro Conference on
+ * Real-Time Systems (ECRTS 2013), July 2013.  It is a generalization of the
+ * Priority Ceiling Protocol to SMP systems.  Each MrsP semaphore uses a
+ * ceiling priority per scheduler instance.  A task obtaining or owning a MrsP
+ * semaphore will execute with the ceiling priority for its scheduler instance
+ * as specified by the MrsP semaphore object.  Tasks waiting to get ownership
+ * of a MrsP semaphore will not relinquish the processor voluntarily.  In case
+ * the owner of a MrsP semaphore gets preempted it can ask all tasks waiting
+ * for this semaphore to help out and temporarily borrow the right to execute
+ * on one of their assigned processors.
+ *
+ * @{
+ */
+
+/**
+ * @brief MrsP status code.
+ *
+ * The values are chosen to directly map to RTEMS status codes.  In case this
+ * implementation is used for other APIs, then for example the errno values can
+ * be added with a bit shift.
+ */
+typedef enum {
+  MRSP_SUCCESSFUL = 0,
+  MRSP_TIMEOUT = 6,
+  MRSP_INVALID_NUMBER = 10,
+  MRSP_RESOUCE_IN_USE = 12,
+  MRSP_UNSATISFIED = 13,
+  MRSP_INCORRECT_STATE = 14,
+  MRSP_INVALID_PRIORITY = 19,
+  MRSP_NOT_OWNER_OF_RESOURCE = 23,
+  MRSP_NO_MEMORY = 26,
+
+  /**
+   * @brief Internal state used for MRSP_Rival::status to indicate that this
+   * rival waits for resource ownership.
+   */
+  MRSP_WAIT_FOR_OWNERSHIP = 255
+} MRSP_Status;
+
+typedef struct MRSP_Control MRSP_Control;
+
+/**
+ * @brief MrsP rival.
+ *
+ * The rivals are used by threads waiting for resource ownership.  They are
+ * registered in the MrsP control block.
+ */
+typedef struct {
+  /**
+   * @brief The node for registration in the MrsP rival chain.
+   *
+   * The chain operations are protected by the MrsP control lock.
+   *
+   * @see MRSP_Control::Rivals.
+   */
+  Chain_Node Node;
+
+  /**
+   * @brief The corresponding MrsP control block.
+   */
+  MRSP_Control *resource;
+
+  /**
+   * @brief Identification of the rival thread.
+   */
+  Thread_Control *thread;
+
+  /**
+   * @brief The initial priority of the thread at the begin of the resource
+   * obtain sequence.
+   *
+   * Used to restore the priority after a release of this resource or timeout.
+   */
+  Priority_Control initial_priority;
+
+  /**
+   * @brief The initial help state of the thread at the begin of the resource
+   * obtain sequence.
+   *
+   * Used to restore this state after a timeout.
+   */
+  Scheduler_Help_state initial_help_state;
+
+  /**
+   * @brief The rival status.
+   *
+   * Initially the status is set to MRSP_WAIT_FOR_OWNERSHIP.  The rival will
+   * busy wait until a status change happens.  This can be MRSP_SUCCESSFUL or
+   * MRSP_TIMEOUT.  State changes are protected by the MrsP control lock.
+   */
+  volatile MRSP_Status status;
+} MRSP_Rival;
+
+/**
+ * @brief MrsP control block.
+ */
+struct MRSP_Control {
+  /**
+   * @brief Basic resource control.
+   */
+  Resource_Control Resource;
+
+  /**
+   * @brief A chain of MrsP rivals waiting for resource ownership.
+   *
+   * @see MRSP_Rival::Node.
+   */
+  Chain_Control Rivals;
+
+  /**
+   * @brief Lock to protect the resource dependency tree.
+   */
+  ISR_LOCK_MEMBER( Lock )
+
+  /**
+   * @brief The initial priority of the owner before it was elevated to the
+   * ceiling priority.
+   */
+  Priority_Control initial_priority_of_owner;
+
+  /**
+   * @brief One ceiling priority per scheduler instance.
+   */
+  Priority_Control *ceiling_priorities;
+};
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* RTEMS_SMP */
+
+#endif /* _RTEMS_SCORE_MRSP_H */