[U-Boot] coreboot and u-boot integration x86: "No tick base available"

[Martin Ertsås]

On 06/03/14 03:43, Simon Glass wrote:
> Hi Martin,
>
> On 1 June 2014 23:59, Martin Ertsås <martiert at gmail.com> wrote:
>> On 06/01/14 18:42, Simon Glass wrote:
>>> Hi Martin,
>>>
>>> On 30 May 2014 04:33, Martin Ertsås <martiert at gmail.com> wrote:
>>>> Hi.
>>>>
>>>> I'm trying to use u-boot as a payload to coreboot. Problem is that when
>>>> coreboot starts u-boot, it fails with panic("No tick base available");
>>>>
>>>> When looking at the backtrace this gives a recursive error, as panic
>>>> calls __udelay and get_ticks, which again panics. I heard this was
>>>> because u-boot overwrote the memory location of coreboot, and that there
>>>> have been some patches going around that fixes this issue, but have not
>>>> made it upstream. As far as I can tell, chromebook v2 uses these patches
>>>> to make their stuff boot. Can anyone point me in the right direction for
>>>> those patches? I have tried finding them myself, but can't seem to find
>>>> them.
>>>>
>>> It probably means that Coreboot is not passing its timing data to
>>> U-Boot. You need to enable a timestamp option in Coreboot to do this.
>>>
>>> You could patch it to remove this panic and just use 0 in this case.
>>>
>>> Regards,
>>> Simon
>> Thanks. I'll look into the timestamp option. So using 0 as the tick
>> value should work?
> Yes, although you won't get boot timing from Coreboot then. One of the
> engineers favoured a panic() to avoid accidentally dropping the
> function from Coreboot's build. Perhaps it could be changed to be a
> default in Coreboot? This is the second time the issue has come up in
> U-Boot.
>
> Also I'd be happy with printing a warning in this case if you want to
> do a patch.
>
> Regards,

Ok. Looked into enabeling it in coreboot though, but couldn't find a way
to do it with a qemu machine. Guess I'll have to nag the coreboot
developers a bit :)

In one way it was kind of frustrating, but I do see the reason for
having it as a panic though. You have probably done something wrong if
you forgot to enable ticks. I don't feel like I know u-boot well enough
to make a decision if it should be a panic or a warning though. If you
would preffer a warning I can make the patch.

- Martin