Re: [PATCH 1/6] dt-bindings: soc: qcom: Add interconnect binding for GENI QUP

Rob Herring
2019-02-23T00:26:59Z

On Wed, Jan 23, 2019 at 08:41:20PM +0200, Georgi Djakov wrote:
> Hi,
>
> On 1/23/19 19:07, Bjorn Andersson wrote:
> > On Mon 21 Jan 22:33 PST 2019, Alok Chauhan wrote:
> >
> >> Add documentation for the interconnect and interconnect-names bindings
> >> for the GENI QUP as detailed by bindings/interconnect/interconnect.txt.
> >>
> >> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
> >> ---
> >> Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt | 10 ++++++++++
> >> 1 file changed, 10 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
> >> index dab7ca9..44d7e02 100644
> >> --- a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
> >> +++ b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
> >> @@ -17,6 +17,12 @@ Required properties if child node exists:
> >> - #address-cells: Must be <1> for Serial Engine Address
> >> - #size-cells: Must be <1> for Serial Engine Address Size
> >> - ranges: Must be present
> >> +- interconnects: phandle to a interconnect provider. Please refer
> >> + ../interconnect/interconnect.txt for details.
> >> + Must be 2 paths corresponding to 2 AXI ports.
> >> +- interconnect-names: Port names to differentiate between the
> >
> > s/Port names/Path names/
> >
> >> + 2 interconnect paths defined with interconnect
> >> + specifier.
> >
> > These two names are significant in that they must match what the driver
> > expects, hence you must actually specify them here.
> >
> > And as the scope of these strings are local to the QUP node you can omit
> > "qup" from them, so make them "memory" and "config" (or perhaps iface,
> > to match the clock naming?).
>
> Actually there was a discussion in the past where we decided include
> both the src and dst endpoint names in this property so that there is
> some symmetry with the "interconnects" property. It would be nice to be
> consistent across different drivers at least for now.
> If we want to denote the master and slave ports here, my two cents would
> be for "qup-mem" and "cpu-qup" or something similar?

Well, there's a proposal from Maxime to add 'dma-memory' or something.
You all need to sort this out.

I assume config or cpu-qup is for register access? Why is this needed?
That should get described thru the DT tree. The interconnect stuff was
supposed to be for the non-cpu centric view (i.e. DMA masters). Maybe
it's fine, but that's not my initial reaction.

Rob