[Buildroot] [PATCH 1/1] boot/uboot: add config option for uboot environment padding byte

[Yann E. MORIN <yann.morin.1998@free.fr>]

Thomas, Johannes, All,

On 2017-12-12 06:27 +0100, Thomas Petazzoni spake thusly:
> On Mon, 11 Dec 2017 19:47:08 +0100, Johannes Schmitz wrote:
[--SNIP--]
> > +config BR2_TARGET_UBOOT_ENVIMAGE_PADDING_BYTE
> > +	hex "Padding byte"
> > +	default 0x00
> > +	help
> > +	  The byte used for padding at the end of the environment image.
> 
> I'm still not sure what is the point of customizing the padding byte.
> Does someone has a use-case for that ? If not, I'm not sure it makes
> sense to add a Buildroot option for it.

As far as I understand, this is because the U-Boot on Johannes' board
would expect the padding byte to be 0x00 when the default for mkenvimage
is 0xFF.

I have no idea why U-Boot expects 0x00 in Johannes' case, though. The
only thing I can think of is that the 'default' byte value on flash
after a page-erase depends on the technology: for NOR, the value after
erase ix 0x00, while for NAND, it is 0xFF. So maybe that's the reason...

But any case, as you said in a further reply, adding that new option
does not add much complexity.

Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

Regards,
Yann E. MORIN.

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