Hello Zoran,

[1-3] I am using the latest Ubuntu 16.04 LTS x64 desktop, 4.4 kernel. 
[4] I don't know exactly if it's x64 or x86. I have no control over AMI BIOS since it's just a binary I flash into the SPI ROM, which supports the board.
[5] I boot Linux using legacy mode (in AMI, the Linux was installed for legacy boot on the HDD/SSD which connects via USB - USBtoSATA)
[6] I'm not sure. So I have the following checked:
- Run VGA Option ROMs, Native Mode
- Add a VGA BIOS image -> 3rdparty/blobs.../VBIOS.bin
- Set framebuffer resolution (any, without this + above, I have no HDMI output)
[7] It's the same one referenced from Coreboot in the external payloads - GRUB 2.02 beta3.

From your view where would the overflow / boot problems come from ?

Thank you,
Grigore

On Mon, Nov 28, 2016 at 6:31 PM, Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
Hello Grigore,

I have here some dummy questions (forgive me for my ignorance), but I need to ask them just for the sake of curiosity (maybe, after all, we can get somewhere if I articulate questions in the right direction/right format for this problem):

> If I put a proprietary AMI BIOS, GRUB2 works without issue in gfxterm mode and boots Linux without issue.

[1] What Linux architecture are you using (32 or 64)?
[2] Which Linux distro?
[3] Which kernel version?

If you put AMI BIOS, the following questions I would like to know:

[4] Are you using 32 or 64 BIOS?
[5] Which mode are you using for booting (legacy/CSM ON or UEFI/CSM OFF)?
[6] In the accordance with [5], what video component you have set with CMOS: vBIOS or GOP driver?

Not sure, but it seems to me that you are using too old/outdated GRUB2 version (or maybe I am also mistaken)?
[7] Could you tell us, which GRUB2 version you are using?

Thank you,
Zoran

On Mon, Nov 28, 2016 at 7:13 PM, Grigore Lupescu via coreboot <coreboot@coreboot.org> wrote:
Hello,

I am trying to run Linux through the GRUB2 payload. I am not tied to GRUB2 but it's the only payload that gives me HDMI output (board has no serial port) using Coreboot and AMD FT3B-LC.

I have the latest Coreboot sources, have set config accordingly (e.g. CONFIG_MAINBOARD_SMBIOS_PRODUCT_NAME="DB-FT3b-LC"...), getting an image on HDMI and the GRUB2 payload is executing.
In GRUB2 payload I seem to have an overflow issue possibly related to the vga_text mode. If I put a proprietary AMI BIOS, GRUB2 works without issue in gfxterm mode and boots Linux without issue.

Using Coreboot every time the screen gets full of text, GRUB2 re-executes. If I though set the terminal_output to cbmemc then commands would execute but Linux still fails to execute - at the end GRUB2 would restart.

Also the GRUB2 payload on Coreboot does see the drive/files and attempts to execute - I looks like a GRUB2/Coreboot config/code problem.

I execute the below in GRUB2 (which work on AMI BIOS + GRUB2).
grub> set root=(hd0,gpt2)
grub> linux /boot/vmlinuz-3.13.0-29-generic root=/dev/sda2
grub> initrd /boot/initrd.img-3.13.0-29-generic
grub> boot

1. Would anyone have any recommendation about the overflow in GRUB2 payload ? - related to Coreboot.
2. Any suggestions on booting Linux given this board's limitations on output (HDMI only) ?

Thank you,
Grigore

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