imx6 flashing sparse image using uuu

maos — Fri, 20 Jan 2023 07:13:19 GMT

Hi!

Working on an imx6ull based board.

We are creating a custom image in yocto where we have a rather large but empty partition (ext4 filesystem created in this partition but no data).

Downloading the resulting image takes about 10 minutes but we need to reduce this time.

So far we have used:
uuu -b emmc_all <path to u-boot> <path to .wic.bz2 file>/*

Looking at the the decompressed .wic file it is about 3.6 G but most of this should be zeros/empty space.

I think one can draw this conclusion also looking at the generated rootfs.wic.bmap-file as it states:

<ImageSize> 3790602240 </ImageSize>

<BlockSize> 4096 </BlockSize>

<BlocksCount> 925440 </BlocksCount>

<MappedBlocksCount> 131631 </MappedBlocksCount>

Also tried to convert the .wic file using android's img2simg.
When trying the resulting file using the inbuild "emmc_all" script the bootloader started (booting from bootpartition?) but couldn't find a partition table.

Have also made various attempts using a custom uuu-script based on the "emmc_all" inbuilt scipt.

Is there some way to do a "sparse flashing" using uuu?
And could someone point me to how to do this?

thanks,
Mårten

Re: imx6 flashing sparse image using uuu

AldoG — Fri, 20 Jan 2023 18:30:25 GMT

Hello,

A couple of tips that can reduce the time of flashing would be:

- Do not use wic.bz2 use standard .wic file, since the tool will decompress first and then start flashing.
- Try build one smaller image.
- Remove message from uart port. Debug message takes some time to transfer to uart port even when it's not connected.

Best regards,
Aldo.

i.MX Processorsのトピックimx6 flashing sparse image using uuu

imx6 flashing sparse image using uuu

Re: imx6 flashing sparse image using uuu