[PATCH 24/32] pci: PCIe driver for Marvell Armada 370/XP systems

Thierry Reding thierry.reding at avionic-design.de
Fri Mar 8 14:12:27 EST 2013


On Fri, Mar 08, 2013 at 09:52:28AM -0700, Jason Gunthorpe wrote:
> On Fri, Mar 08, 2013 at 08:14:44AM +0100, Thierry Reding wrote:
> > On Thu, Mar 07, 2013 at 06:05:33PM -0600, Rob Herring wrote:
> > > On 03/07/2013 02:47 PM, Thierry Reding wrote:
> > [...]
> > > > In a nutshell (since some of the context isn't quoted anymore) the
> > > > problem that we're trying to solve is that some of the embedded SoCs
> > > > require per-root-port registers for configuration. The PCI DT
> > > > specification doesn't make any provisions for this. A few alternatives
> > > > have been discussed so far:
> > > 
> > > I'm not sure I follow. This is different than the host controller
> > > registers? Why would this not just be multiple entries in the reg property?
> > 
> > Well the register regions are per root-port. On Tegra20 there's 2 of
> > them, Tegra30 has 3 and if I understand correctly Marvell can have up to
> > 10 (!). Adding all of them to the reg property of the host controller
> > could work but it needs some way to match the reg entry to the root port
> > similar to option 1 below.
> 
> Thomas just posted an implementation like this, please see:
> 
> http://www.spinics.net/lists/arm-kernel/msg228749.html

Oh well. I don't like it, but if that's the way it has to be, then so be
it. Any reason why the reg-names can't match the root port's node name
so that it can be used directly instead of going through hoops to
construct a string from extra parameters? Like below:

	pcie-controller {
		regs = <...>;
		reg-names = ..., "pcie at 1,0", "pcie at 2,0";

		pcie at 1,0 {
			...
		};

		pcie at 2,0 {
			...
		};
	};

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 836 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20130308/c48fa649/attachment.sig>


More information about the linux-arm-kernel mailing list