[PATCH v7 5/6] Documentation: dt-bindings: pci: altera pcie device tree binding
Ley Foon Tan
lftan at altera.com
Fri Oct 2 00:56:16 PDT 2015
On Tue, Sep 29, 2015 at 3:38 AM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Monday 28 September 2015 12:31:36 Rob Herring wrote:
>> >> > +
>> >> > +Required properties:
>> >> > +- compatible : should contain "altr,pcie-root-port-1.0"
>> >> > +- reg: a list of physical base address and length for TXS and CRA.
>> >> > +- reg-names: must include the following entries:
>> >> > + "Txs" or "txs": TX slave port region
>> >> > + "Cra" or "cra": Control register access region
>> >> Why both cases? Can we please just have one (or none is better IMO).
>> > The PCIe IP on different device families use different register names.
>> > And our device tree generator will auto generate the register names
>> > based on the hardware description name. Too bad we can't change the
>> > hardware description names now.
>> Okay, your problem to maintain. Hopefully the driver just goes by index then.
>> Strictly speaking, if you have undocumented bindings downstream that
>> is your problem and we don't have to accept them as-is upstream. I'm
>> not going to worry about that here.
> Are they always in the same order? If you don't mandate any names for the
> registers in the binding but just use them by index, we can keep that
> bit of ugliness out of the binding and the driver and still be compatible
> with all the devices.
Too bad the order might change in future devices. We will fix the
tool, so only have one reg-name case.
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