[coreboot] and/or busybox issue with alix2c3 serial console

Roman Yeryomin leroi.lists at gmail.com
Wed Nov 5 01:21:44 CET 2008


On Wed, Nov 5, 2008 at 2:01 AM, ron minnich <rminnich at gmail.com> wrote:
> depending on how daring you feel, you can (I have done this) do an
> open of /dev/console IN THE KERNEL, and see what happens. But based on
> what we're seeing so far, I am pretty strongly convinced there is an
> interrupt issue here.

well.. I'm not really good programmer, but I can dig there and see
what I can do, or you can give me some patch I can try...
BTW some time ago, when I was starting to play with coreboot and
already had this issue (there are posts in this list about month ago)
I've asked Pascal Dornier (person behind pcengines - alix board maker)
how he sets up uart in his bios (as seems like he wrote it himself)
and here is what he replied (I've already posted this):

>seems like there is a bug in coreboot and it's not setting uart the
>right way. I can see all the coreboot and kernel messages in console but
>right after init starts serial console is lost (linux keeps running
>normally).
>So.. could you share how you set up uarts in your tinyBIOS? Which
>UART[x]_MOD, UART[x]_DON and UART[x]_CONF bits you set?

After init -> changes to Linux driver, or does it still use Int 10 + Int 16 ?
My BIOS does a redirect of these BIOS interrupts to the serial console.
Once the Linux kernel starts it has to take care of the serial console itself.

I didn't reply him because didn't know what to say.
tinybios source code is available on pcengines website but it's
written in assembler (and I don't understand anything there) -- maybe
it can help somehow?


Roman




More information about the coreboot mailing list