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Date: Sun, 19 Jul 2009 10:08:17 -0500
From: Olof Johansson <olof@lixom.net>
To: Michael Ellerman <michael@ellerman.id.au>
Subject: Re: [PATCH] powerpc/mpic: Fix MPIC_BROKEN_REGREAD on non broken MPICs
Message-ID: <20090719150817.GA22099@lixom.net>
References: <6c9c0889feaceeea55bd2b6fef0c19e408425ef5.1246846125.git.michael@ellerman.id.au>
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On Mon, Jul 06, 2009 at 12:08:52PM +1000, Michael Ellerman wrote:
> The workaround enabled by CONFIG_MPIC_BROKEN_REGREAD does not work
> on non-broken MPICs. The symptom is no interrupts being received.
> 
> The fix is twofold. Firstly the code was broken for multiple isus,
> we need to index into the shadow array with the src_no, not the idx.
> Secondly, we always do the read, but only use the VECPRI_MASK and
> VECPRI_ACTIVITY bits from the hardware, the rest of "val" comes
> from the shadow.
> 
> Signed-off-by: Michael Ellerman <michael@ellerman.id.au>

Signed-off-by: Olof Johansson <olof@lixom.net>

Tested OK here on an electra. Thanks for fixing this!


-Olof