+int mlx4_check_ext_port_caps(struct mlx4_dev *dev, u8 port)
+{
+ struct mlx4_cmd_mailbox *inmailbox, *outmailbox;
+ u8 *inbuf, *outbuf;
+ int err, packet_error;
+
+ inmailbox = mlx4_alloc_cmd_mailbox(dev);
+ if (IS_ERR(inmailbox))
+ return PTR_ERR(inmailbox);
+
+ outmailbox = mlx4_alloc_cmd_mailbox(dev);
+ if (IS_ERR(outmailbox)) {
+ mlx4_free_cmd_mailbox(dev, inmailbox);
+ return PTR_ERR(outmailbox);
+ }
+
+ inbuf = inmailbox->buf;
+ outbuf = outmailbox->buf;
+ memset(inbuf, 0, 256);
+ memset(outbuf, 0, 256);
+ inbuf[0] = 1;
+ inbuf[1] = 1;
+ inbuf[2] = 1;
+ inbuf[3] = 1;
+
+ *(__be16 *) (&inbuf[16]) = MLX4_ATTR_EXTENDED_PORT_INFO;
+ *(__be32 *) (&inbuf[20]) = cpu_to_be32(port);
+
+ err = mlx4_cmd_box(dev, inmailbox->dma, outmailbox->dma, port, 3,
+ MLX4_CMD_MAD_IFC, MLX4_CMD_TIME_CLASS_C);
+
+ packet_error = be16_to_cpu(*(__be16 *) (outbuf + 4));
+
+ dev->caps.ext_port_cap[port] = (!err && !packet_error) ?
+ MLX_EXT_PORT_CAP_FLAG_EXTENDED_PORT_INFO
+ : 0;
+
+ mlx4_free_cmd_mailbox(dev, inmailbox);
+ mlx4_free_cmd_mailbox(dev, outmailbox);
+ return err;
+}
+