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Subject: Re: [PATCH v9 2/3] PCI: Add a macro to set default alignment for
 all PCI devices
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>, Bjorn Helgaas
 <helgaas@kernel.org>,
        Yongji Xie <xyjxie@linux.vnet.ibm.com>
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        linuxppc-dev@lists.ozlabs.org, alex.williamson@redhat.com,
        gwshan@linux.vnet.ibm.com, aik@ozlabs.ru, paulus@samba.org,
        zhong@linux.vnet.ibm.com
Date: Mon, 27 Mar 2017 21:25:50 +1100
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On Mon, 2017-03-27 at 21:17 +1100, Michael Ellerman wrote:
> > If so, is it acceptable to force that kernel to user 64K alignment
> > even
> > when it's running on non-PowerNV systems?
> 
> Probably, but I'm not sure TBH. Benh will know, I'll try and get his
> attention.

Can we make the alignment PAGE_SIZE ? I think that should be ok as long
as it doesn't try to re-allocate BARs for devices that have already
been properly allocated by firmware (ie, PowerMac, if you mess around
with the MacIO chip on these, bad things will happen).

Cheers,
Ben.