On Sun, 2017-10-08 at 23:57 -0300, Javier Romero wrote:
> Andrew,
> 
> Thans for your answer.
> 
> Bug reported: https://github.com/openbmc/openbmc/issues/2434
> 
> I`d like to try to cook up a patch, but do I need to know a specific
> language programming to do this ?

Hmm, good question. This is probably a bug in how a bitbake
configuration/recipe configures the kernel. As such I'd suggest getting a
handle on Yocto, which is the build and configuration system we use. Here's the
quick start guide:

http://www.yoctoproject.org/docs/2.1/yocto-project-qs/yocto-project-qs.html

There's also a rather daunting Mega Manual, which is useful as a reference
(rather than reading the whole thing):

http://www.yoctoproject.org/docs/2.1/mega-manual/mega-manual.html

Back to the bug itself, from the output that you gave I expect it's some issue
with the following directive:

https://github.com/openbmc/openbmc/blob/master/meta-phosphor/conf/distro/openbmc-phosphor.conf#L57

i.e. the issue is that that linux-raspberrypi (the kernel recipe used for the
raspberry pi[1][2]) doesn't have a 'phosphor-gpio-keys' feature. The implicit
assumption is that the configuration will be using the linux-obmc tree[3][4][5], which
is our fork of the kernel (primarily for Aspeed SoC support).

More generally, knowledge of Python (Yocto/bitbake, some OpenBMC userspace), C
(u-boot, kernel, qemu, also requires a some comfort with assembler) and C++ (most
of the phosphor reference userspace applications) is useful.

Hope that helps.

Andrew

[1] https://github.com/openbmc/openbmc/blob/4f2d85233d23eedaf1d4846d3d861ba28bc49b00/import-layers/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi_4.4.bb
[2] https://github.com/openbmc/openbmc/blob/4f2d85233d23eedaf1d4846d3d861ba28bc49b00/import-layers/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi.inc
[3] https://github.com/openbmc/openbmc/blob/4f2cddf103aaca6df26ddb766655fdf49c56a6ae/meta-phosphor/common/recipes-kernel/linux/linux-obmc_4.10.bb
[4] https://github.com/openbmc/openbmc/blob/4f2cddf103aaca6df26ddb766655fdf49c56a6ae/meta-phosphor/common/recipes-kernel/linux/linux-obmc.inc