Inquiry on how to make sdcard into bz2

[kiyoung]

I am developing in the imx-image-core environment using IMX8MP. (6.1-mickledore imx8mp-lpddr4-evk)

I created device.sdcard by combining kernel, rootfs, my_disk, etc.
When written with uuu, it works well.

The sdcard file was compressed with bz2.
The method for making an sdcard file into bz2 is as follows.
tar cvfj device.sdcard.bz2 device.sdcard
When I wrote the bz2 file with uuu, the write operation was completed, but kernel booting failed.
"uuu.exe -b emmc_all imx-boot-imx8mp-lpddr4-evk-sd.bin-flash_evk device.sdcard.bz2"

Device 0: unknown device
MMC: no card present
switch to partitions #0, OK
mmc2(part 0) is current device
** No partition table - mmc 2 **
Couldn't find partition mmc 2:1

Where did it go wrong?

[Rita_Wang]

For detailed usage of UUU, see github.com/NXPmicro/mfgtools/wiki.

[Rita_Wang]

Are you using NXP reference board or the board you designed yourself? Have you choose the proper boot device, I see that you are going to downlaod images to emmc.

[kiyoung]

I have an NXP reference board and designed the board based on it.
The created iamge is downloaded to mmc.
The core question is that the uncompressed image works, but the compressed image I created does not work.

[Rita_Wang]

Hi @kiyoung 

For the uncompressed image works well, do you build them yourself or the demo images?

[kiyoung · Accepted solution]

As I wrote in the question, I assembled the image myself.
I used zstd instead of bz2, and it worked well.
The UUU documentation I have (by nxpfrankli) says to use bz2, so I did that.
bz2 does not write compressed files correctly.
zstd works fine.
thank you.