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Date: Fri, 21 Feb 2014 10:31:05 -0700
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
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	Ezequiel Garcia <ezequiel.garcia@free-electrons.com>,
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	Gregory Cl??ment <gregory.clement@free-electrons.com>
Subject: Re: pci-mvebu driver on km_kirkwood
Message-ID: <20140221173105.GA17611@obsidianresearch.com>
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On Fri, Feb 21, 2014 at 06:05:08PM +0100, Thomas Petazzoni wrote:
 
> Now I have another question: our mvebu_pcie_align_resource() function
> makes sure that the base address of the BAR is aligned on its size,
> because it is a requirement of MBus windows. However, if you later
> split the BAR into multiple windows, will this continue to work out?

No, you must align to (1 << log2_round_down(size)) - that will always
be the largest mbus window created and thus the highest starting
alignment requirement.

I looked for a bit to see if I could find why the core is rounding up
to 196MB and it wasn't clear to me either.

Gerlando, if you instrument the code in setup-bus.c, particularly
pbus_size_mem, you will probably find out.

Jason