bricked device

[gl40]

About two months ago, I tried a firmware update which ended badly: the card no longer works and seem's bricked
=> unable to reboot with an sdcard.
=> No device appears on the USB port.
But there is a little sign of life when I plug in the debug port:
$ lsusb -v
....
Bus 001 Device 051: ID 0403:6011 Future Technology Devices International, Ltd FT4232H Quad HS USB-UART/FIFO IC
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0403 Future Technology Devices International, Ltd
idProduct 0x6011 FT4232H Quad HS USB-UART/FIFO IC
bcdDevice 8.00
iManufacturer 1 Xilinx
iProduct 2 Xilinx Debugger
iSerial 3 DebugChannel
...

Is it possible to reinstall firmware with the debug usb port? how ? Found some stuff with openOCD, but this tool is not so simple...

another idea to unbrick the card ?