Add device tree bindings for CDX bus controller.

Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
---
 .../bindings/bus/xlnx,cdxbus-controller.yaml  | 68 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 69 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml

diff --git a/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
new file mode 100644
index 000000000000..b2f186864021
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
@@ -0,0 +1,68 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/xlnx,cdxbus-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AMD CDX bus controller
+
+description: |
+  CDX bus controller for AMD devices is implemented to dynamically
+  detect CDX bus and devices on these bus using the firmware.
+  The CDX bus manages multiple FPGA based hardware devices, which
+  can support network, crypto or any other specialized type of
+  devices. These FPGA based devices can be added/modified dynamically
+  on run-time.
+
+  All devices on the CDX bus will have a unique streamid (for IOMMU)
+  and a unique device ID (for MSI) corresponding to a requestor ID
+  (one to one associated with the device). The streamid and deviceid
+  are used to configure SMMU and GIC-ITS respectively.
+
+  iommu-map property is used to define the set of stream ids
+  corresponding to each device and the associated IOMMU.
+
+  The MSI writes are accompanied by sideband data (Device ID).
+  The msi-map property is used to associate the devices with the
+  device ID as well as the associated ITS controller.
+
+  rproc property (xlnx,rproc) is used to identify the remote processor
+  with which APU (Application Processor Unit) interacts to find out
+  the bus and device configuration.
+
+maintainers:
+  - Nipun Gupta <nipun.gupta@amd.com>
+  - Nikhil Agarwal <nikhil.agarwal@amd.com>
+
+properties:
+  compatible:
+    const: xlnx,cdxbus-controller
+
+  iommu-map: true
+
+  msi-map: true
+
+  xlnx,rproc:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      phandle to the remoteproc_r5 rproc node using which APU interacts
+      with remote processor.
+
+required:
+  - compatible
+  - iommu-map
+  - msi-map
+  - xlnx,rproc
+
+additionalProperties: false
+
+examples:
+  - |
+    cdxbus-controller {
+        compatible = "xlnx,cdxbus-controller";
+        /* define map for RIDs 250-259 */
+        iommu-map = <250 &smmu 250 10>;
+        /* define msi map for RIDs 250-259 */
+        msi-map = <250 &its 250 10>;
+        xlnx,rproc = <&remoteproc_r5>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 25c76cf27f21..b43242546b17 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -966,6 +966,7 @@ AMD CDX BUS DRIVER
 M:	Nipun Gupta <nipun.gupta@amd.com>
 M:	Nikhil Agarwal <nikhil.agarwal@amd.com>
 S:	Maintained
+F:	Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
 F:	drivers/bus/cdx/*
 F:	include/linux/cdx/*
 
-- 
2.17.1

On 17/01/2023 14:41, Nipun Gupta wrote:
> Add device tree bindings for CDX bus controller.

Subject: drop second/last, redundant "device tree bindings". The
"dt-bindings" prefix is already stating that these are bindings.

> 
> Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
> ---
>  .../bindings/bus/xlnx,cdxbus-controller.yaml  | 68 +++++++++++++++++++
>  MAINTAINERS                                   |  1 +
>  2 files changed, 69 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
> 
> diff --git a/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
> new file mode 100644
> index 000000000000..b2f186864021
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
> @@ -0,0 +1,68 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/bus/xlnx,cdxbus-controller.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: AMD CDX bus controller
> +
> +description: |
> +  CDX bus controller for AMD devices is implemented to dynamically
> +  detect CDX bus and devices on these bus using the firmware.
> +  The CDX bus manages multiple FPGA based hardware devices, which
> +  can support network, crypto or any other specialized type of
> +  devices. These FPGA based devices can be added/modified dynamically
> +  on run-time.
> +
> +  All devices on the CDX bus will have a unique streamid (for IOMMU)
> +  and a unique device ID (for MSI) corresponding to a requestor ID
> +  (one to one associated with the device). The streamid and deviceid
> +  are used to configure SMMU and GIC-ITS respectively.
> +
> +  iommu-map property is used to define the set of stream ids
> +  corresponding to each device and the associated IOMMU.
> +
> +  The MSI writes are accompanied by sideband data (Device ID).
> +  The msi-map property is used to associate the devices with the
> +  device ID as well as the associated ITS controller.
> +
> +  rproc property (xlnx,rproc) is used to identify the remote processor
> +  with which APU (Application Processor Unit) interacts to find out
> +  the bus and device configuration.
> +
> +maintainers:
> +  - Nipun Gupta <nipun.gupta@amd.com>
> +  - Nikhil Agarwal <nikhil.agarwal@amd.com>
> +
> +properties:
> +  compatible:
> +    const: xlnx,cdxbus-controller

This misses SoC specific compatible. Drop "bus" - redundant. I would
also say - drop controller - do you see any other devices with such
compatible naming? Use naming consistent with other devices in the
kernel. Just open some controllers - SPI, I2C etc. and look there.

> +
> +  iommu-map: true

No mask?

> +
> +  msi-map: true
> +
> +  xlnx,rproc:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      phandle to the remoteproc_r5 rproc node using which APU interacts
> +      with remote processor.
> +
> +required:
> +  - compatible
> +  - iommu-map
> +  - msi-map
> +  - xlnx,rproc
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    cdxbus-controller {

Node names should be generic, so just cdx.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> +        compatible = "xlnx,cdxbus-controller";
> +        /* define map for RIDs 250-259 */
> +        iommu-map = <250 &smmu 250 10>;

Best regards,
Krzysztof

[AMD Official Use Only - General]



> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Sent: Tuesday, January 17, 2023 11:24 PM
> To: Gupta, Nipun <Nipun.Gupta@amd.com>; robh+dt@kernel.org;
> krzysztof.kozlowski+dt@linaro.org; gregkh@linuxfoundation.org;
> rafael@kernel.org; eric.auger@redhat.com; alex.williamson@redhat.com;
> cohuck@redhat.com; song.bao.hua@hisilicon.com;
> mchehab+huawei@kernel.org; maz@kernel.org; f.fainelli@gmail.com;
> jeffrey.l.hugo@gmail.com; saravanak@google.com; Michael.Srba@seznam.cz;
> mani@kernel.org; yishaih@nvidia.com; jgg@ziepe.ca; jgg@nvidia.com;
> robin.murphy@arm.com; will@kernel.org; joro@8bytes.org;
> masahiroy@kernel.org; ndesaulniers@google.com; linux-arm-
> kernel@lists.infradead.org; linux-kbuild@vger.kernel.org; linux-
> kernel@vger.kernel.org; devicetree@vger.kernel.org
> Cc: okaya@kernel.org; Anand, Harpreet <harpreet.anand@amd.com>; Agarwal,
> Nikhil <nikhil.agarwal@amd.com>; Simek, Michal <michal.simek@amd.com>;
> git (AMD-Xilinx) <git@amd.com>
> Subject: Re: [PATCH 03/19] dt-bindings: bus: add CDX bus controller device tree
> bindings
> 
> Caution: This message originated from an External Source. Use proper caution
> when opening attachments, clicking links, or responding.
> 
> 
> On 17/01/2023 14:41, Nipun Gupta wrote:
> > Add device tree bindings for CDX bus controller.
> 
> Subject: drop second/last, redundant "device tree bindings". The
> "dt-bindings" prefix is already stating that these are bindings.

Agree. Will update.

> 
> >
> > Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
> > ---
> >  .../bindings/bus/xlnx,cdxbus-controller.yaml  | 68 +++++++++++++++++++
> >  MAINTAINERS                                   |  1 +
> >  2 files changed, 69 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/bus/xlnx,cdxbus-
> controller.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/bus/xlnx,cdxbus-
> controller.yaml b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-
> controller.yaml
> > new file mode 100644
> > index 000000000000..b2f186864021
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/bus/xlnx,cdxbus-controller.yaml
> > @@ -0,0 +1,68 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/bus/xlnx,cdxbus-controller.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: AMD CDX bus controller
> > +
> > +description: |
> > +  CDX bus controller for AMD devices is implemented to dynamically
> > +  detect CDX bus and devices on these bus using the firmware.
> > +  The CDX bus manages multiple FPGA based hardware devices, which
> > +  can support network, crypto or any other specialized type of
> > +  devices. These FPGA based devices can be added/modified dynamically
> > +  on run-time.
> > +
> > +  All devices on the CDX bus will have a unique streamid (for IOMMU)
> > +  and a unique device ID (for MSI) corresponding to a requestor ID
> > +  (one to one associated with the device). The streamid and deviceid
> > +  are used to configure SMMU and GIC-ITS respectively.
> > +
> > +  iommu-map property is used to define the set of stream ids
> > +  corresponding to each device and the associated IOMMU.
> > +
> > +  The MSI writes are accompanied by sideband data (Device ID).
> > +  The msi-map property is used to associate the devices with the
> > +  device ID as well as the associated ITS controller.
> > +
> > +  rproc property (xlnx,rproc) is used to identify the remote processor
> > +  with which APU (Application Processor Unit) interacts to find out
> > +  the bus and device configuration.
> > +
> > +maintainers:
> > +  - Nipun Gupta <nipun.gupta@amd.com>
> > +  - Nikhil Agarwal <nikhil.agarwal@amd.com>
> > +
> > +properties:
> > +  compatible:
> > +    const: xlnx,cdxbus-controller
> 
> This misses SoC specific compatible. Drop "bus" - redundant. I would
> also say - drop controller - do you see any other devices with such
> compatible naming? Use naming consistent with other devices in the
> kernel. Just open some controllers - SPI, I2C etc. and look there.

Makes sense. Will use "xlnx,cdx" in compatible.

> 
> > +
> > +  iommu-map: true
> 
> No mask?

Currently there is no use for iommu-map-mask as RID's are one to
one mapped stream ID's, so we have not added this optional property.

> 
> > +
> > +  msi-map: true
> > +
> > +  xlnx,rproc:
> > +    $ref: /schemas/types.yaml#/definitions/phandle
> > +    description:
> > +      phandle to the remoteproc_r5 rproc node using which APU interacts
> > +      with remote processor.
> > +
> > +required:
> > +  - compatible
> > +  - iommu-map
> > +  - msi-map
> > +  - xlnx,rproc
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    cdxbus-controller {
> 
> Node names should be generic, so just cdx.
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-
> basics.html#generic-names-recommendation

Sure. Will update to cdx.

Thanks,
Nipun

> 
> > +        compatible = "xlnx,cdxbus-controller";
> > +        /* define map for RIDs 250-259 */
> > +        iommu-map = <250 &smmu 250 10>;
> 
> Best regards,
> Krzysztof

On 18/01/2023 13:39, Gupta, Nipun wrote:
> [AMD Official Use Only - General]

Fix your email client. This is not helping us. What shall I do with it?


> 
> 
> 

(...)


>>> +properties:
>>> +  compatible:
>>> +    const: xlnx,cdxbus-controller
>>
>> This misses SoC specific compatible. Drop "bus" - redundant. I would
>> also say - drop controller - do you see any other devices with such
>> compatible naming? Use naming consistent with other devices in the
>> kernel. Just open some controllers - SPI, I2C etc. and look there.
> 
> Makes sense. Will use "xlnx,cdx" in compatible.

No, this still misses device specific compatible. You did ignored half
of my comment now.


Best regards,
Krzysztof

> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Sent: Wednesday, January 18, 2023 6:13 PM
> To: Gupta, Nipun <Nipun.Gupta@amd.com>; robh+dt@kernel.org;
> krzysztof.kozlowski+dt@linaro.org; gregkh@linuxfoundation.org;
> rafael@kernel.org; eric.auger@redhat.com; alex.williamson@redhat.com;
> cohuck@redhat.com; song.bao.hua@hisilicon.com;
> mchehab+huawei@kernel.org; maz@kernel.org; f.fainelli@gmail.com;
> jeffrey.l.hugo@gmail.com; saravanak@google.com; Michael.Srba@seznam.cz;
> mani@kernel.org; yishaih@nvidia.com; jgg@ziepe.ca; jgg@nvidia.com;
> robin.murphy@arm.com; will@kernel.org; joro@8bytes.org;
> masahiroy@kernel.org; ndesaulniers@google.com; linux-arm-
> kernel@lists.infradead.org; linux-kbuild@vger.kernel.org; linux-
> kernel@vger.kernel.org; devicetree@vger.kernel.org
> Cc: okaya@kernel.org; Anand, Harpreet <harpreet.anand@amd.com>; Agarwal,
> Nikhil <nikhil.agarwal@amd.com>; Simek, Michal <michal.simek@amd.com>;
> git (AMD-Xilinx) <git@amd.com>
> Subject: Re: [PATCH 03/19] dt-bindings: bus: add CDX bus controller device tree
> bindings

(...)

> >>> +properties:
> >>> +  compatible:
> >>> +    const: xlnx,cdxbus-controller
> >>
> >> This misses SoC specific compatible. Drop "bus" - redundant. I would
> >> also say - drop controller - do you see any other devices with such
> >> compatible naming? Use naming consistent with other devices in the
> >> kernel. Just open some controllers - SPI, I2C etc. and look there.
> >
> > Makes sense. Will use "xlnx,cdx" in compatible.
> 
> No, this still misses device specific compatible. You did ignored half
> of my comment now.

Sorry I missed that part. Will rename this to "xlnx,versal-cdx".

Thanks,
Nipun

> 
> 
> Best regards,
> Krzysztof