Re: [coreboot] Embedded Controller (EC)

[Randall Spangler]

On Fri, Dec 1, 2017 at 6:32 AM, Vadim Bendebury 
wrote:
> [+cc a couple of guys who might have some advice in this respect]
>
> On Fri, Dec 1, 2017 at 5:07 AM, Аладышев Константин 
> wrote:
> > Hello! I'm trying to understand, what is the easiest way today to
> > integrate
> > EC to custom motherboard? What controller should I choose for new custom
> > motherboard?
> > First of all, are there any ECs on market that ship with embedded
> >
> > firmware, where all you need to do is just a little bit of register
> > configuration (like SuperIO)? Or is it always like you need to write all
> > firmware by yourself?

Most EC vendors that sell dedicated ECs also sell their SDK and source
code, but it's not cheap.  So usually roll your own, hopefully based on an
open design.
> In that case what is the main difference between
> > ordinary microcontroller (for example STM32) and some controller marked by
> > vendor as EC?

Interfaces.  EC will have:

- Keyboard scanner
   - eSPI / LPC for connecting to x86 SoC
   - More I2C ports

(and in the old days, PECI and PS/2 ports).
> > How stable and flexible are projects about open EC firmware? Is it
> >
> > possible to adapt these projects for my custom motherboard?
> >
> > I'm talking about:
> > Chromium Embedded Controller:
> >
> > http://www.chromium.org/chromium-os/ec-development

This is used on all current Chromebooks, so it's full-featured and stable.
We do tend to branch old boards, so if your motherboard has an old chipset
on it you may need to look back in time to find support for it.
> > Origami-EC: https://git.code.paulk.fr/gitw
> >
> > eb/?p=origami-ec.git;a=summary
> > What is the current status of EC support from coreboot point of view?
> >
> > https://review.coreboot.org/cgit/coreboot.git/tree/src/ec
> >
> > Best regards,
> > Aladyshev Konstantin