Linux FPGA Manager driver creates /sys/kernel/debug/fpga/ folder, which contains image attributes that provides readback contents.
- readback_type : /sys/module/zynqmp_fpga/parameters/readback_type readback_type is a module parameter which tells the readback type (default : 0) 0 – Configuration Register read 1 - Configuration Data read
- image : /sys/kernel/debug/fpga/<fpga>/image image is a debugfs attribute which provides the readback information based on the readback_type module param
Steps for Readback of Configuration Registers
S et flags for readback type
echo 0 > /sys/module/zynqmp_fpga/parameters/readback_type
Perform Readback operation by reading the image debug attribute
cat /sys/kernel/debug/fpga/fpga0/image
Example:
root@xilinx-zcu102-2018_3:~# echo 0 > /sys/module/zynqmp_fpga/parameters/readback_type root@xilinx-zcu102-2018_3:~# cat /sys/kernel/debug/fpga/fpga0/image zynqMP FPGA Configuration register contents are CRC --> 0 FAR --> 7fc0000 FDRI --> 0 FDRO --> effffffe CMD --> d CTRL0 --> 101 MASK --> 0 STAT --> 16907ffc LOUT --> 0 COR0 --> 38003fe5 MFWR --> 0 CBC --> 0 IDCODE --> 1484a093 AXSS --> 0 COR1 --> 400000 WBSTR --> 0 TIMER --> 0 BOOTSTS --> 1 CTRL1 --> 0
Steps for Readback of Configuration DataFrames
S et flags for readback type
echo 1 > /sys/module/zynqmp_fpga/parameters/readback_type
Perform Readback operation by reading the image debug attribute
cat /sys/kernel/debug/fpga/fpga0/image
Example:
root@xilinx-zcu102-2018_3:~# echo 1 > /sys/module/zynqmp_fpga/parameters/readback_type root@xilinx-zcu102-2018_3:~# cat /sys/kernel/debug/fpga/fpga0/image > reabackdata.bin root@xilinx-zcu102-2018_3:~# hexdump readbackdata.bin > data.txt