Running the IO server

Adam Lackorzynski adam at
Mon Jul 11 23:34:52 CEST 2011

Hi Anna,

On Mon Jul 11, 2011 at 16:43:58 +0100, Anna Fischer wrote:
> I'm trying to run the ARM-based frame buffer configuration from
> conf/examples/arm-rv-lcd.cfg with pkg/io/config/arm-rv-eb-mc.devs and
> QEMU (-M realview-pbx-a9). I can boot the L4 Linux kernel on this
> (without GUI but just serial I/O) configuration, but I get an error when
> trying to set up the LCD (see below). 
> Perhaps the LCD device configuration from the .devs file does not match
> what hardware QEMU emulates? How can I actually enumerate in the IO
> server what hardware it actually runs on? Is there a way to do that?
> MOE: rom name space cap -> [C:501000]
>   BOOTFS: [1190000-11906bb] [C:503000] arm-rv-lcd.cfg
>   BOOTFS: [1191000-119159d] [C:504000] arm-rv-eb-mc.devs
>   BOOTFS: [1192000-11920e4] [C:505000]
>   BOOTFS: [1193000-11ac510] [C:506000] l4re
>   BOOTFS: [11ad000-1287b58] [C:507000] io
>   BOOTFS: [1288000-12db1b8] [C:508000] ned
>   BOOTFS: [12dc000-13055b8] [C:509000] fb-drv
>   BOOTFS: [1306000-139346c] [C:50a000] mag
>   BOOTFS: [1394000-13b5c7c] [C:50b000] ex_fb_spectrum
> MOE: cmdline: moe rom/arm-rv-lcd.cfg
> MOE: Starting: rom/ned rom/arm-rv-lcd.cfg
> MOE: loading 'rom/ned'
> Ned says: Hi World!
> Ned: loading file: 'rom/arm-rv-lcd.cfg'
> IO      | Io service
> mag     | libio: Warning: Finding 'icu' in system bus failed with 'Void
> capability invoked'

I think the problem is 'just' that io hides its error messages when not
being fed with -v (just corrected). Thus we do not see the proper output
which I guess says that it cannot find one of the config files. Did you
also change the file name in arm-rv-lcd.cfg? Anyway, on Qemu
arm-rv-eb.devs is the right one, as unlike on hardware Qemu takes the
realview-eb interrupt configuration also on pbx so that PS/2 works with
this setup. It does not matter for the LCD.
To see what io knows, add more -v's to it.

Adam                 adam at

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