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Subject: Re: [RFC/PATCH 4/7] Powerpc MSI implementation
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
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Date: Wed, 08 Nov 2006 13:08:00 +1100
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Cc: Matthew Wilcox <matthew@wil.cx>, Greg Kroah-Hartman <greg@kroah.com>,
	Ingo Molnar <mingo@elte.hu>,
	Russell King <rmk-pci@arm.linux.org.uk>, linuxppc-dev@ozlabs.org,
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On Tue, 2006-11-07 at 18:33 -0700, Eric W. Biederman wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> 
> >> For message signalled interrupts and hyptertransport interrupts we probably
> > want
> >> to add an additional field for pointing to their per irq state.  Per device
> >> interrupt controllers are truly peculiar.
> >
> > A per-irq addition field for the MSI data might indeed be useful. I
> > still want to store it in the pci_dev, but it would be good to have a
> > pointer to it in the irq_desc.
> 
> The msi_info in pci_dev is reasonable.  But storing all 4096 possible
> msi_desc's in pci_dev seems a little much.

My initial idea was that the msi_info structure would have a variable
lenght, that is, would end with msi_desc[0] and would be allocated to
the the right size, but it might suck a bit :-)

> Hopefully I can look at this a little more this evening and see what we
> need to do to harmonize the two msi implementations.

Thanks !

Ben.