[infiniband] Add a standalone subnet management agent

This generic SMA code can be used for any cards that do not provide
firmware-based embedded SMAs.

src/include/gpxe/errfile.h

@@ -135,6 +135,7 @@
 #define ERRFILE_netdev_settings		( ERRFILE_NET | 0x00140000 )
 #define ERRFILE_dhcppkt			( ERRFILE_NET | 0x00150000 )
 #define ERRFILE_slam			( ERRFILE_NET | 0x00160000 )
+#define ERRFILE_ib_sma			( ERRFILE_NET | 0x00170000 )
 
 #define ERRFILE_image		      ( ERRFILE_IMAGE | 0x00000000 )
 #define ERRFILE_elf		      ( ERRFILE_IMAGE | 0x00010000 )

src/include/gpxe/ib_sma.h

@@ -0,0 +1,63 @@
+#ifndef _GPXE_IB_SMA_H
+#define _GPXE_IB_SMA_H
+
+/** @file
+ *
+ * Infiniband Subnet Management Agent
+ *
+ */
+
+#include <gpxe/infiniband.h>
+#include <gpxe/process.h>
+
+/** Infiniband Subnet Management Agent operations */
+struct ib_sma_operations {
+	/** Set port information
+	 *
+	 * @v ibdev		Infiniband device
+	 * @v port_info		New port information
+	 */
+	int ( * set_port_info ) ( struct ib_device *ibdev,
+				  const struct ib_port_info *port_info );
+};
+
+/** An Infiniband Subnet Management Agent */
+struct ib_sma {
+	/** Infiniband device */
+	struct ib_device *ibdev;
+	/** SMA operations */
+	struct ib_sma_operations *op;
+	/** SMA completion queue */
+	struct ib_completion_queue *cq;
+	/** SMA queue pair */
+	struct ib_queue_pair *qp;
+	/** Poll process */
+	struct process poll;
+};
+
+/** SMA payload size allocated for received packets */
+#define IB_SMA_PAYLOAD_LEN 2048
+
+/** SMA number of send WQEs
+ *
+ * This is a policy decision.
+ */
+#define IB_SMA_NUM_SEND_WQES 4
+
+/** SMA number of receive WQEs
+ *
+ * This is a policy decision.
+ */
+#define IB_SMA_NUM_RECV_WQES 2
+
+/** SMA number of completion queue entries
+ *
+ * This is a policy decision
+ */
+#define IB_SMA_NUM_CQES 8
+
+extern int ib_create_sma ( struct ib_sma *sma, struct ib_device *ibdev,
+			   struct ib_sma_operations *op );
+extern void ib_destroy_sma ( struct ib_sma *sma );
+
+#endif /* _GPXE_IB_SMA_H */