Fiasco.OC (rev. 40) Pandaboard support

Stefan Kalkowski stefan.kalkowski at
Fri Sep 7 14:39:21 CEST 2012

Hi L4-hackers,

recently I've tried to adapt Genode's Fiasco.OC-platform support to use
the latest Fiasco.OC/L4Re subversion revision. When trying it on x86 I
didn't run into any trouble. It worked "out of the box".
But when it came to ARM, I got problems to boot Fiasco.OC on the
Pandaboard in general (also when using plain Fiasco.OC/L4Re).

I've debugged the problem down to Cpu::init_errata_workarounds(). The
problem is that pandaboard's boot code initializes TrustZone, and
triggers a configuration-disable signal beforehand. That leads to
'undefined instruction' exceptions, whenever one tries to write into the
p15/c15-c0-1 debug register (like it's done in init_errata_workarounds).
The attached patch implements Cpu::init_errata_workarounds() empty for
the pandaboard. Moreover, it restricts the appliance of ERRATA 743622 to
CPU revisions: r2p0-r2p2.

With the attached patch Fiasco.OC runs fine on the Pandaboard too.

Best regards

Stefan Kalkowski
Genode Labs ·

Genode Labs GmbH · Amtsgericht Dresden · HRB 28424 · Sitz Dresden
Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth
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