L4Android and L4Linux parallel on an i.MX53

Tobias Fink tobias.fink at stud.h-da.de
Tue Apr 17 12:09:36 CEST 2012


> Do I understand correctly that L4Linux talks successfully to the UART?
> (You're only showing parts of the iol4lx_tf.io file?) Then this would be
> a pure Linux thing. Something like this: prog </dev/ttyLv1 >/dev/ttyLv1 2&>1

I'm showing the full .io file. I have just used another cfg (without
starting the L4Linux) for testing.
Well L4Linux talks to the UART that it detects automatically.
A Linux kernel sees that one as follows:
[    0.969085] serial8250.2: ttyS2 at MMIO 0x49020000 (irq = 74) is a ST16654

L4 says during startup:
SERIAL ESC: allocated IRQ 74 for serial uart

and L4Linux:
console [ttyLv0] enabled
ttyLv0 at MMIO 0x1 (irq = 210) is a L4

What I'm trying to do is to use another UART to communicate with a
second L4Linux on top of L4.
This is the UART I'm trying to use
[    0.598999] serial8250.0: ttyS0 at MMIO 0x4806a000 (irq = 72) is a ST16654
(note that there was a mistake in my .io file where the other UART was
initialized. I changed that without any effect).

So as I understand it I have to initialize the second interface and
give it to the second L4Linux when booting with "console=....".
Is there more documentation on the cfg files other then on
http://os.inf.tu-dresden.de/L4Re/doc/l4re_getting_started.html ? I
can't find any and have to work with the examples I find in this List
and the sources.

> You should put both devices into the same bus, otherwise the first one
> will not appear.

I changed that with no change as far as I can see.

Regards Tobi

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