FPGA loader

On this page, you will find all the informations needed to use the Linux FPGA loader driver. This driver allows you to load the FPGA of your APF board from Linux userspace/shell (ie FPGA reprogrammation after Linux boot).

Module compilation & installation

• The first thing you have to do is to activate the driver in the Linux configuration:

$ make linux26-menuconfig

Device Drivers ---> 
    Armadeus specific drivers --->
        FPGA Drivers   --->
            <M>     Armadeus FPGA configuration driver

• rebuild Linux or the complete rootfs

$ make

Once your rootfs reflashed, you will find the new driver in the /lib/modules/drivers/... subdirectories on your target. If you don't want to reflash the complete rootfs, take a look at this page to know how/where to manually copy the driver on your board.

In the Host directory target/linux/modules/fpga/dev_tools/fpga_devtools/ you will find a script named fpgaloader.sh.

Copy this script on the target and launch it:

# sh fpgaloader.sh

This will load (=modprobe) the driver.

Remark

The default FPGA version is the Spartan3 200k. The version can be changed when installing the module:

 # modprobe fpgaloader fpga_descriptor=0     (for a 200K)

and:

 # modprobe fpgaloader fpga_descriptor=1     (for a 400k)

These informations are given by the /proc interface.

Driver usage

• The FPGA loader driver is usable through the standard Linux filesystem interface. To read the available configurations, do:

# cat /proc/driver/fpga/loader 

• The displayed sizes correspond to the different FPGA versions supported by the board:
  • 130k: Spartan 200k
  • 212k: Spartan 400k

• To upload a new firmware (here bramtest_top_apf.bin), use:

# dd if=bramtest_top_apf.bin of=/dev/fpga/fpgaloader