[U-Boot] U-Boot on nyan-big via legacy boot

[Simon Glass]

Hi,

On 9 December 2014 at 11:19, SimonH <simon.hoinkis at codethink.co.uk> wrote:
> Hi Simon,
>
> On 04/12/14 15:53, Simon Glass wrote:
>>> [715.979284 HC 0xd2]
>>
>> This is a reboot command - EC_CMD_REBOOT_EC. I wonder how/why your
>> U-Boot might issue that command?
>
> From my investigation, Coreboot is issuing this reboot command, because the
> Coreboot payload (which in my case is U-Boot) for some reason isn't valid.

Normally you would hope for lots of AP serial output in this case.

> With CONFIG_PANIC_HANG defined there is no UART output from the EC at all.
> Is a prepended SPL needed before the U-Boot+DTB payload?

I don't think so, but I have not tried.

>
> When flashing U-Boot from the Chromium OS branch it gives some UART output
> but freezes because SPI and MMC driver are not working properly
> ("emerge-nyan chromeos-u-boot").
> Is this the best starting point to develop a working U-Boot?

Yes, and I'm not sure of the state in the branch. Which branch?

See u-boot-dm/nyan-working for an upstream version. It boots (at least
from USB A-A) and the display comes up. To do: EC, keyboard, USB,
maybe other things.

Regards,
Simon