BCM53xx on D-Link DIR-890L - 2MB max problem

[Linus Walleij]

On Fri, Jan 13, 2023 at 11:11 PM Arınç ÜNAL <arinc.unal at arinc9.com> wrote:

> Side question, did you risk writing your test builds to the flash or
> have you already got the flash in an easily reprogrammable set up?

This device has the boot prom in NOR so firmware is only flashed
to the NAND flash, no risk of overwriting the boot loader.

> I tried letting U-Boot's lzmadec decompress the kernel image.
> Decompressing fails when the kernel size reaches a certain point.

Hm haven't tried that, I used a zImage and I added u-boot
CMD_BOOTZ to U-boot so it can start it directly without any
external compression or funny uImage stuff.

> Since the image is compressed in the end, I can't exactly add bytes and
> predict what the size of the compressed file will be. So after a lot of
> compiling and trying on the board, this is the closest I got.
>
> LZMA compressed kernel size in bytes which U-Boot’s lzmadec can decompress:
> 19134096
>
> LZMA compressed kernel size in bytes which U-Boot’s lzmadec fails to
> decompress:
> 19134142
(...)
> I was wondering if there's a limit the bootloader sets for the lzma
> decompressor. I assume it's 2 MiB for CFE.

Hm. I guess this could be a limitation in some implementations
of the algorithm simply...

> Did you try booting a kernel on this Northstar SoC with U-Boot?

Haven't gotten there yet, I need to implement SEAMA support
(the D-Link preferred NAND image format) first, because it
totally scrambles the stuff written to flash.

Yours,
Linus Walleij