diff --git a/sys/dev/isp/isp_ioctl.h b/sys/dev/isp/isp_ioctl.h
index 64613fd8bc6..f0294c806b1 100644
--- a/sys/dev/isp/isp_ioctl.h
+++ b/sys/dev/isp/isp_ioctl.h
@@ -156,3 +156,26 @@ struct isp_hba_device {
 #define	ISP_TOPO_FPORT		4	/* F-port */
 
 #define	ISP_FC_GETHINFO	_IOR(ISP_IOC, 12, struct isp_hba_device)
+/*
+ * Set some internal parameters. This doesn't take effect until
+ * the chip is reset.
+ *
+ * Each parameter is generalized to be a name string with an integer value.
+ *
+ * Known parameters are:
+ *
+ *	Name				Value Range
+ *	
+ *	"framelength"			512,1024,2048
+ *	"exec_throttle"			16..255
+ *	"fullduplex"			0,1
+ *	"loopid"			0..125
+ */
+
+struct isp_fc_param {
+	char		param_name[16];	/* null terminated */
+	u_int32_t	parameter;
+};
+
+#define	ISP_GET_FC_PARAM	_IOWR(ISP_IOC, 98, struct isp_fc_param)
+#define	ISP_SET_FC_PARAM	_IOWR(ISP_IOC, 99, struct isp_fc_param)