Re: [PATCH v2] arm64: defconfig: enable EEPROM_AT25 config option

From: Scott Branden
Date: Tue Oct 18 2016 - 18:23:53 EST




On 16-10-18 01:48 PM, Olof Johansson wrote:
On Tue, Oct 18, 2016 at 1:38 PM, Scott Branden
<scott.branden@xxxxxxxxxxxx> wrote:
Hi Olof,

On 16-10-17 05:04 PM, Olof Johansson wrote:

On Mon, Oct 17, 2016 at 4:24 PM, Scott Branden
<scott.branden@xxxxxxxxxxxx> wrote:

Hi Olof,

On 16-10-17 02:58 PM, Olof Johansson wrote:


Hi,

On Wed, Oct 12, 2016 at 11:51 AM, Scott Branden
<scott.branden@xxxxxxxxxxxx> wrote:


Enable support for on board SPI EEPROM by turning on
CONFIG_EEPROM_AT25. This needs to be on in order to
boot and test the kernel with a static rootfs image
that is not rebuilt everytime the kernel is rebuilt.



If we did this for every kernel option we'd get a huge kernel.

In general, we've said that static options for what's needed to boot
to rootfs (i.e. storage and network drivers for nfsroot) are fine to
enable statically.

I doubt you need the EEPROM driver to boot to rootfs on your system,
so please enable it as a module instead.

OK, I will upstream as module and need config fragments maintained locally
in order to test defconfig on our test setup.

Great.



Look into using config fragments in case you need to modify the
options for local builds, it should be a convenient way to have a
small delta to apply to fit your internal needs, instead of completely
forking the config file.



Do you allow such config fragments to be upstreamed or do we need to
maintain these in our tree?


There's no place for them upstream. Maintain locally or in a separate
repo.

If that is the case - shall we cleanup arch/arm/configs and delete
dram_0x00000000.config that was introduced in the 4.4 kernel?

That one is a bit different, in that it allows us to do defconfig
consolidation, and as such keeps the number of defconfigs needed down.

In particular, see the email from Arnd here:

http://marc.info/?l=linux-arm-kernel&m=145700132713703

Thanks for link.

I have be.config and le.config that allow you to switch the defconfig
between big and little endian. Does this make sense to upstream to
arm/configs if you have accepted dram_0x00000000.config?

Would you also accept this to arm64/configs? We actually use
big and little endian on the same SoC more on arm64 platforms. But, in
order to boot big endian we need to maintain this outside the kernel
right now.


-Olof