Re: [coreboot] Porting coreboot to new board

[Zvi Vered]

Hello Youness,

Thank you very much for the detailed information !

Can you please tell what is the best starting point for a XEON board ?
I think there are no "Intel® XEON® Processor E3-1505M v5" boards in last
version of coreboot.
Am I right ?

Best regards,
Zvika

On Tue, May 29, 2018 at 9:15 PM Youness Alaoui <
[e-mail]> wrote:
> Hi,
>
> I suggest you read the wiki :
> https://www.coreboot.org/Developer_Manual and
> https://www.coreboot.org/Motherboard_Porting_Guide
> I would also suggest maybe (optional) that you read my blog posts
> about my own experience porting coreboot to a new motherboard :
> https://puri.sm/posts/diving-back-into-coreboot-development/
> https://puri.sm/posts/librem-13-coreboot-report-january-12-2017/
> https://puri.sm/posts/librem-13-coreboot-report-february-3rd-2017/
> https://puri.sm/posts/librem-13-coreboot-report-february-25th-2017/
> https://puri.sm/posts/coreboot-on-the-librem-13-v2-part-1/
> https://puri.sm/posts/coreboot-on-the-skylake-librems-part-2/
>
> To answer your specific questions : It depends on your machine, is it
> AMD or is it Intel? Is it Ivybridge or Broadwell or Skylake or
> Apollolake, etc.. ? Does it have soldered RAM or does it use SODIMMs?
> Depending on the CPU architecture, the CPU 'brand' and even the model
> of the CPU itself, the port will be done very differently. You'd first
> want to find a mainboard that is as close as your current one, and
> start modifying that, there isn't "one mainboard to use as base"
> because the code, files, etc.. are almost unique depending on the
> CPU/northbridge/southbridge model, so use the closest one as your
> base.
> As far as I know, the file board_info.txt is just information about
> the board, it's not getting used by coreboot, it's more of an
> indication for developers.
> As for the other files, it will depend once again on your board. I'd
> say Kconfig and devicetree.cb are mandatory, the rest may or may not
> be mandatory depending on your hardware. The cmos.layout for example
> isn't mandatory, but you'd probably need it if you enable CMOS support
> in your KConfig, The 'spd' files containing the RAM's SPD EEPROM
> information are mandatory only if your board has soldered RAM (common
> in laptops but not in desktops), but they are not needed (and actually
> can't be provided) if the motherboard has SODIMM slots instead. So it
> all depends. Your best bet is to look at what's there and see if you
> need it or not and if you do, understand what it's for and what needs
> to be changed in order to match your board.
> Don't forget that before you get your board to boot with coreboot, you
> will probably have to flash it and brick your board 100 times, so make
> sure you have a backup of your original ROM copied somewhere safe and
> that you have the hardware to re-program the SPI flash externally (and
> test that it works), before you attempt to flash it.
> Also, make sure you are patient, and ready to learn!
>
> Good luck!
> Youness.
>
> On Mon, May 28, 2018 at 10:31 PM, Zvi Vered  wrote:
> > Hello,
> >
> > I have to port coreboot to a new "Mainboard" not listed in menuconfig.
> > Is there a basic "Mainboard" I should use as a starting point that will
>
> be
> > copied to my board ?
> >
> > The file board_info.txt contains few parameters.
> > How can I know the meaning of each parameter and its possible values ?
> >
> > The board kontron/kt690 for example contains few files like: cmos.layout,
> > devicetree.cb, etc
> > Are all those files mandatory ?
> > Is there a list of mandatory files or routines required in order to port
>
> a
> > board ?
> >
> > Your help is highly appreciated.
> > Best regards,
> > Zvika