From mboxrd@z Thu Jan  1 00:00:00 1970
From: wmb@firmworks.com (Mitch Bradley)
Date: Mon, 11 Mar 2013 09:49:10 -1000
Subject: [PATCH 24/32] pci: PCIe driver for Marvell Armada 370/XP systems
In-Reply-To: <20130311182339.GB10992@obsidianresearch.com>
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To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 3/11/2013 8:23 AM, Jason Gunthorpe wrote:
>> (b) The discovery/enumeration code needs to access config space via
>> pci_ops.  The root complex driver implements pci_ops based on a trivial
>> parsing of ranges (omitting irrelevant details):
>>
>> pci_op_read(devfn, pos) {
>>    loop_over_ranges_entries {
>>       if (to_devfn(ranges_entry.child) == devfn) {
>>          return mmio_read(ranges_entry.parent + pos);
>                             ^^^^^^^^^^^^^^^^^^^
> 
> This has to be converted through all enclosing node's ranges prior to
> being used as a CPU address - the OF core has all the code to do this,
> but a new entry point would be needed for this specific application...

Agreed.  But I was considering that detail to be outside the scope of
this discussion because the same thing must happen for any physical
address at this level of the tree.

> 
> Cheers,
> Jason
>