[U-Boot] fw_env.config settings for Digilent ZedBoard (Zynq 7020 Soc)

[Brendan Simon (eTRIX) <brendan.simon@etrix.com.au>]

Hi,

I'm using a Digilent ZedBoard with a Xilinx Zynq 7020 SoC.  The kernel
is from Analog Devices and is a fork of 4.0.0 (according to the Makefile).

I am struggling to work out the fw_env.config file required to use with
fw_printenv/fw_saveenv.
fw_printenv continually gives me CRC error and uses the defaults.

Google hasn't provided much assistance, with some people reporting that
the settings required are different to what /proc/mtd shows.

Here is info from /proc/mtd and my /etc/fw_env.config.

root at bjs:~# cat
/proc/mtd                                                                                                 

dev:    size   erasesize  name
mtd0: 00500000 00010000 "boot"
mtd1: 00020000 00010000 "bootenv"
mtd2: 00020000 00010000 "config"
mtd3: 00a80000 00010000 "image"
mtd4: 01040000 00010000 "spare"

root at bjs:~# cat
/etc/fw_env.config                                                                                                 

# Configuration file for fw_(printenv/setenv) utility.
# Up to two entries are valid, in this case the redundant
# environment sector is assumed present.
# MTD device name       Device offset   Env. size       Flash sector size
#         /dev/mtd1               0x0000          0x20000         0x40000
#         /dev/mtd1               0x0000          0x20000         0x20000
#         /dev/mtd1               0x0000          0x20000         0x10000
#         /dev/mtd2               0x0000          0x20000         0x40000
#         /dev/mtd2               0x0000          0x20000         0x20000
         /dev/mtd2               0x0000          0x20000         0x10000

Does anyone have any insight into what the correct fw_env.config
settings should be from the above info?

How can I find out the correct settings.  Is there a command in u-boot
itself which will report the correct information?

Thanks,
Brendan.