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ExpressMIMO2 drivers and firmware

This page shows how to get started with the ExpressMIMO2 family of cards.


Before compiling you need to set OPENAIRx_DIR to the root directory of openairx, see the file oaienv in the top director of OAI or do something like:

set OPENAIR_HOME variable and export the following:
export OPENAIR1_DIR=$OPENAIR_HOME/openair1
export OPENAIR2_DIR=$OPENAIR_HOME/openair2
export OPENAIR3_DIR=$OPENAIR_HOME/openair3

Also, you should check that Linux has properly identified the card by doing


where you should see something like

01:00.0 Signal processing controller: Xilinx Corporation Default PCIe endpoint ID


Everything can also be compiled comfortably from the directory $OPENAIR_TARGETS/RT/USER using "make drivers". There is a script init_exmimo2.sh which loads the driver and initializes the firmware after auto-detecting the version of the card.

To compile Openair kernel modules yourself

To operate the ExpressMIMO2 cards, you need one hardware driver (linux kernel module). This driver is located in $OPENAIR_TARGETS/ARCH/EXMIMO/DRIVER/eurecom. RTAI is no longer required to build this driver. RTAI is only required for the real-time operation of the card (see below).

To build the driver just call "make" from $OPENAIR_TARGETS/ARCH/EXMIMO/DRIVER/eurecom. It will produce a file "openair_rf.ko" in the same directory. Insert the module using "sudo insmod openair_rf.ko". If you do a dmesg, you should see some kernel logs which trace the initial dialogue between the LEON3 processor in ExpressMIMO2 and the openair_rf driver in the host PC.

Firmware upload

Before using the card, the firmare needs to be loaded in the card. The program to do this is located in $OPENAIR_TARGETS/ARCH/EXMIMO/USERSPACE/OAI_FW_INIT. To build the tool call "make" from that directory.

In the same directory there is the compiled firmware for ExpressMIMO2 (sdr_expressmimo2). If you want to compile the firmware from scratch, look into the openair0 SVN repository, folder exmimo2/software/sdr.

To load the firmware into the card, type "updatefw -s 0x43fffff0 -b -f sdr_expressmimox", where x has to be replaced with the Express MIMO board version.

Again by doing dmesg you can check that the card is operational. You should see the message "[LEON card0]: ready".

Potential Gotchas

When compiling the module, you can safely ignore the warnings at the end of the compilation that several rtai symbols are not found. But, if you see warnings for non RTAI functions, that means that indeed something is wrong in your build process.

When inserting the driver you may get several possible errors. If you get "insmod: error inserting 'openair_rf_softmodem.ko': -1 Unknown symbol in module", check with dmesg which symbol is missing. Most likely, one of the rtai module is not inserted. If you get "insmod: error inserting 'openair_rf_softmodem.ko': -1 No such device", that is pretty obvious: the card is not found.

-- FlorianKaltenberger - 22 Apr 2013

Topic revision: r6 - 01 Aug 2014 - RaymondKnopp
Copyright 2004-2010 Institut Eurecom & all contributing authors.