MPIC Timer of U3

Régis Odeyé rod at
Thu Jan 22 21:41:34 EST 2004


I'm trying to use the MPIC Timer sub-module of the U3 (host bridge on JS20).

First of all, I did not see any API in the kernel except for the
definition of MPIC stucture in open_pic_defs.h, so I added a small
module (dynamically loaded) remapping the mpic structure of the U3
(through ioremap call).

The mapping seems to be OK because I read the Vendor Id properly and I'm
able to read/write to the interruptions part of the MPIC (Source part of
the MPIC structure).

But unfortunately, the Timer Frequency and the Timers seem not to be
programmable (re-read always 0x0).

Is there anybody who experimented such a behaviour with the MPIC Timer
of the U3 ?


Régis Odeyé
Thales Computers, a Thales company.
E-mail: rod at
Tel: +33 (0)4 98 16 34 86 - Fax: +33 (0)4 98 16 34 01

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