RE: [PATCH v2] dt-bindings: fpga: xilinx-pr-decoupler: convert bindings to json-schema

From: Manne, Nava kishore
Date: Thu Feb 23 2023 - 00:12:09 EST


Hi Krzysztof,

Thanks for providing the review comments.
Please find my response inline below.

> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Sent: Wednesday, February 22, 2023 2:54 PM
> To: Manne, Nava kishore <nava.kishore.manne@xxxxxxx>;
> mdf@xxxxxxxxxx; hao.wu@xxxxxxxxx; yilun.xu@xxxxxxxxx; trix@xxxxxxxxxx;
> robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> michal.simek@xxxxxxxxxx; linux-fpga@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2] dt-bindings: fpga: xilinx-pr-decoupler: convert
> bindings to json-schema
>
> On 21/02/2023 12:50, Nava kishore Manne wrote:
> > Convert xilinx-pr-decoupler bindings to DT schema format using
> > json-schema
> >
> > Signed-off-by: Nava kishore Manne <nava.kishore.manne@xxxxxxx>
> > ---
> > Changes for v2:
> > - Updated the description and addressed some minor comments
> > as suggested by Krzysztof.
> >
> > .../bindings/fpga/xilinx-pr-decoupler.txt | 54 --------------
> > .../bindings/fpga/xlnx,pr-decoupler.yaml | 71 +++++++++++++++++++
> > 2 files changed, 71 insertions(+), 54 deletions(-) delete mode
> > 100644 Documentation/devicetree/bindings/fpga/xilinx-pr-decoupler.txt
> > create mode 100644
> > Documentation/devicetree/bindings/fpga/xlnx,pr-decoupler.yaml
> >
> > diff --git
> > a/Documentation/devicetree/bindings/fpga/xilinx-pr-decoupler.txt
> > b/Documentation/devicetree/bindings/fpga/xilinx-pr-decoupler.txt
> > deleted file mode 100644
> > index 0acdfa6d62a4..000000000000
> > --- a/Documentation/devicetree/bindings/fpga/xilinx-pr-decoupler.txt
> > +++ /dev/null
> > @@ -1,54 +0,0 @@
> > -Xilinx LogiCORE Partial Reconfig Decoupler Softcore
> > -
> > -The Xilinx LogiCORE Partial Reconfig Decoupler manages one or more
> > -decouplers / fpga bridges.
> > -The controller can decouple/disable the bridges which prevents signal
> > -changes from passing through the bridge. The controller can also
> > -couple / enable the bridges which allows traffic to pass through the
> > -bridge normally.
> > -
> > -Xilinx LogiCORE Dynamic Function eXchange(DFX) AXI shutdown manager
> > -Softcore is compatible with the Xilinx LogiCORE pr-decoupler.
> > -
> > -The Dynamic Function eXchange AXI shutdown manager prevents AXI
> > traffic -from passing through the bridge. The controller safely
> > handles AXI4MM -and AXI4-Lite interfaces on a Reconfigurable Partition
> > when it is -undergoing dynamic reconfiguration, preventing the system
> > deadlock -that can occur if AXI transactions are interrupted by DFX
> > -
> > -The Driver supports only MMIO handling. A PR region can have multiple
> > -PR Decouplers which can be handled independently or chained via
> > decouple/ -decouple_status signals.
> > -
> > -Required properties:
> > -- compatible : Should contain "xlnx,pr-decoupler-1.00" followed
> by
> > - "xlnx,pr-decoupler" or
> > - "xlnx,dfx-axi-shutdown-manager-1.00" followed by
> > - "xlnx,dfx-axi-shutdown-manager"
> > -- regs : base address and size for decoupler module
> > -- clocks : input clock to IP
> > -- clock-names : should contain "aclk"
> > -
> > -See Documentation/devicetree/bindings/fpga/fpga-region.txt and
> > -Documentation/devicetree/bindings/fpga/fpga-bridge.txt for generic
> bindings.
> > -
> > -Example:
> > -Partial Reconfig Decoupler:
> > - fpga-bridge@100000450 {
> > - compatible = "xlnx,pr-decoupler-1.00",
> > - "xlnx-pr-decoupler";
> > - regs = <0x10000045 0x10>;
> > - clocks = <&clkc 15>;
> > - clock-names = "aclk";
> > - bridge-enable = <0>;
> > - };
> > -
> > -Dynamic Function eXchange AXI shutdown manager:
> > - fpga-bridge@100000450 {
> > - compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> > - "xlnx,dfx-axi-shutdown-manager";
> > - regs = <0x10000045 0x10>;
> > - clocks = <&clkc 15>;
> > - clock-names = "aclk";
> > - bridge-enable = <0>;
> > - };
> > diff --git
> > a/Documentation/devicetree/bindings/fpga/xlnx,pr-decoupler.yaml
> > b/Documentation/devicetree/bindings/fpga/xlnx,pr-decoupler.yaml
> > new file mode 100644
> > index 000000000000..4a08d4bfa20d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/fpga/xlnx,pr-decoupler.yaml
> > @@ -0,0 +1,71 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/fpga/xlnx,pr-decoupler.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Xilinx LogiCORE Partial Reconfig Decoupler/AXI shutdown
> > +manager Softcore
> > +
> > +maintainers:
> > + - Nava kishore Manne <nava.kishore.manne@xxxxxxx>
> > +
> > +description: The Xilinx LogiCORE Partial Reconfig Decoupler manages
> > +one or more
>
> Blank line before text... don't use your own style. Use style consistent with
> the project.
>
> > + decouplers / fpga bridges. The controller can decouple/disable the
> > + bridges which prevents signal changes from passing through the
> > + bridge. The controller can also couple / enable the bridges which
> > + allows traffic to pass through the bridge normally.
> > + Xilinx LogiCORE Dynamic Function eXchange(DFX) AXI shutdown manager
> > + Softcore is compatible with the Xilinx LogiCORE pr-decoupler. The
> > + Dynamic Function eXchange AXI shutdown manager prevents AXI traffic
> > + from passing through the bridge. The controller safely handles
> > + AXI4MM and AXI4-Lite interfaces on a Reconfigurable Partition when
> > + it is undergoing dynamic reconfiguration, preventing the system
> > + deadlock that can occur if AXI transactions are interrupted by DFX.
> > + Please refer to fpga-region.txt and fpga-bridge.txt in this
> > + directory for common binding part and usage.
> > +
> > +properties:
> > + compatible:
> > + oneOf:
> > + - items:
> > + - const: xlnx,pr-decoupler-1.00 #For PR-Decoupler.
>
> Drop the comment, it duplicates the compatible. There is no point in it.
>
> > + - const: xlnx,pr-decoupler
> > + - items:
> > + - const: xlnx,dfx-axi-shutdown-manager-1.00 #For AXI shutdown
> manager.
>
> Ditto
>
> > + - const: xlnx,dfx-axi-shutdown-manager
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + clocks:
> > + maxItems: 1
> > +
> > + clock-names:
> > + items:
> > + - const: aclk
> > +
> > + bridge-enable:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + enum: [0, 1]
> > + description:
> > + Zero if driver should disable bridge at startup. One if driver should
> > + enable bridge at startup. Default is to leave bridge in current state.
>
> This property wasn't in original binding. Even though it is fpga-bridge.txt, why
> do you need it? It's not used. Also, do not describe driver but rather
> hardware.

I agree, this is not relevant to the H/W property.
Will drop this in v3.

Regards,
Navakishore.