Re: [PATCH v2 5/5] doc: edison: Rewrite the update instructions

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Wed, Jun 17, 2026 at 08:41:30AM +0200, Andy Shevchenko wrote:
> On Tue, Jun 16, 2026 at 08:24:20AM -0600, Simon Glass wrote:
> > Split the two ways of getting U-Boot onto the board: a plain DFU
> > transfer into u-boot0 when a working U-Boot is already present, and the
> > xFSTK mask ROM recovery when it is not. Drop the steps that only applied
> > to replacing the original 2014 U-Boot, document the 4KB alignment gap
> > the mask ROM needs and which binman output to flash (rather than the
> > bare u-boot.bin), note that a bricked board enters DnX without any
> > straps, and add udev rules for running the tools without sudo.

...

> > -1. Prepare u-boot.bin as described in chapter above. You still need one
> > -   more step (if and only if you have original U-Boot), i.e. run the
> > -   following command::
> >  
> > -     $ truncate -s %4096 u-boot.bin
> 
> Still missing this important detail. The DFU on v2014.04 is broken in a way
> that it requires also the whole binary to be aligned by 4k. The above pads
> the tail to full 4k (last block).
> 
> Btw, now I realised that I haven't checked if this is inherited in your binman
> case. Note, I haven't put that into the Makefile hack as I expected users to
> do this once, but perhaps if somebody wants to start over (by flashing the last
> official image), the file size needs to be aligned.

TL;DR: Either we leave this in documentation, or we always have a bigger blob.
However I don't remember how (current) upstream U-Boot DFU will react on the
trailing garbage (nulls).

-- 
With Best Regards,
Andy Shevchenko