diff mbox series

[v3,1/6] dt-bindings: PCI: Add binding for qps615

Message ID 20241112-qps615_pwr-v3-1-29a1e98aa2b0@quicinc.com (mailing list archive)
State New
Headers show
Series PCI: Enable Power and configure the QPS615 PCIe switch | expand

Commit Message

Krishna Chaitanya Chundru Nov. 12, 2024, 3:01 p.m. UTC
Add binding describing the Qualcomm PCIe switch, QPS615,
which provides Ethernet MAC integrated to the 3rd downstream port
and two downstream PCIe ports.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
 .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
 1 file changed, 205 insertions(+)

Comments

Bjorn Andersson Nov. 12, 2024, 3:49 p.m. UTC | #1
On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> Add binding describing the Qualcomm PCIe switch, QPS615,
> which provides Ethernet MAC integrated to the 3rd downstream port
> and two downstream PCIe ports.
> 

Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Regards,
Bjorn

> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
>  1 file changed, 205 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> new file mode 100644
> index 000000000000..e6a63a0bb0f3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> @@ -0,0 +1,205 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm QPS615 PCIe switch
> +
> +maintainers:
> +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
> +
> +description: |
> +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
> +  ports. The 3rd downstream port has integrated endpoint device of
> +  Ethernet MAC. Other two downstream ports are supposed to connect
> +  to external device.
> +
> +  The QPS615 PCIe switch can be configured through I2C interface before
> +  PCIe link is established to change FTS, ASPM related entry delays,
> +  tx amplitude etc for better power efficiency and functionality.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - pci1179,0623
> +
> +  reg:
> +    maxItems: 1
> +
> +  i2c-parent:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    description: |
> +      A phandle to the parent I2C node and the slave address of the device
> +      used to do configure qps615 to change FTS, tx amplitude etc.
> +    items:
> +      - description: Phandle to the I2C controller node
> +      - description: I2C slave address
> +
> +  vdd18-supply: true
> +
> +  vdd09-supply: true
> +
> +  vddc-supply: true
> +
> +  vddio1-supply: true
> +
> +  vddio2-supply: true
> +
> +  vddio18-supply: true
> +
> +  reset-gpios:
> +    maxItems: 1
> +    description:
> +      GPIO controlling the RESX# pin.
> +
> +  qps615,axi-clk-freq-hz:
> +    description:
> +      AXI clock rate which is internal bus of the switch
> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
> +    enum: [125000000, 250000000]
> +
> +allOf:
> +  - $ref: "#/$defs/qps615-node"
> +
> +patternProperties:
> +  "@1?[0-9a-f](,[0-7])?$":
> +    description: child nodes describing the internal downstream ports
> +      the qps615 switch.
> +    type: object
> +    $ref: "#/$defs/qps615-node"
> +    unevaluatedProperties: false
> +
> +$defs:
> +  qps615-node:
> +    type: object
> +
> +    properties:
> +      qcom,l0s-entry-delay-ns:
> +        description: Aspm l0s entry delay.
> +
> +      qcom,l1-entry-delay-ns:
> +        description: Aspm l1 entry delay.
> +
> +      qcom,tx-amplitude-millivolt:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Change Tx Margin setting for low power consumption.
> +
> +      qcom,no-dfe-support:
> +        type: boolean
> +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
> +          intersymbol interference and some reflections caused by impedance mismatches.
> +
> +      qcom,nfts:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
> +          for bit and Symbol lock.
> +
> +    allOf:
> +      - $ref: /schemas/pci/pci-bus.yaml#
> +
> +unevaluatedProperties: false
> +
> +required:
> +  - vdd18-supply
> +  - vdd09-supply
> +  - vddc-supply
> +  - vddio1-supply
> +  - vddio2-supply
> +  - vddio18-supply
> +  - i2c-parent
> +  - reset-gpios
> +
> +examples:
> +  - |
> +
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    pcie {
> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +
> +        pcie@0 {
> +            device_type = "pci";
> +            reg = <0x0 0x0 0x0 0x0 0x0>;
> +
> +            #address-cells = <3>;
> +            #size-cells = <2>;
> +            ranges;
> +            bus-range = <0x01 0xff>;
> +
> +            pcie@0,0 {
> +                compatible = "pci1179,0623";
> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
> +                device_type = "pci";
> +                #address-cells = <3>;
> +                #size-cells = <2>;
> +                ranges;
> +                bus-range = <0x02 0xff>;
> +
> +                i2c-parent = <&qup_i2c 0x77>;
> +
> +                vdd18-supply = <&vdd>;
> +                vdd09-supply = <&vdd>;
> +                vddc-supply = <&vdd>;
> +                vddio1-supply = <&vdd>;
> +                vddio2-supply = <&vdd>;
> +                vddio18-supply = <&vdd>;
> +
> +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
> +
> +                pcie@1,0 {
> +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x03 0xff>;
> +
> +                    qcom,no-dfe-support;
> +                };
> +
> +                pcie@2,0 {
> +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x04 0xff>;
> +
> +                    qcom,nfts = <10>;
> +                };
> +
> +                pcie@3,0 {
> +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x05 0xff>;
> +
> +                    qcom,tx-amplitude-millivolt = <10>;
> +                    pcie@0,0 {
> +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
> +                        #address-cells = <3>;
> +                        #size-cells = <2>;
> +                        device_type = "pci";
> +                        ranges;
> +
> +                        qcom,l1-entry-delay-ns = <10>;
> +                    };
> +
> +                    pcie@0,1 {
> +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
> +                        #address-cells = <3>;
> +                        #size-cells = <2>;
> +                        device_type = "pci";
> +                        ranges;
> +
> +                        qcom,l0s-entry-delay-ns = <10>;
> +                    };
> +                };
> +            };
> +        };
> +    };
> 
> -- 
> 2.34.1
>
Rob Herring (Arm) Nov. 15, 2024, 4:18 p.m. UTC | #2
On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> Add binding describing the Qualcomm PCIe switch, QPS615,
> which provides Ethernet MAC integrated to the 3rd downstream port
> and two downstream PCIe ports.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
>  1 file changed, 205 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> new file mode 100644
> index 000000000000..e6a63a0bb0f3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> @@ -0,0 +1,205 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm QPS615 PCIe switch
> +
> +maintainers:
> +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
> +
> +description: |
> +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
> +  ports. The 3rd downstream port has integrated endpoint device of
> +  Ethernet MAC. Other two downstream ports are supposed to connect
> +  to external device.
> +
> +  The QPS615 PCIe switch can be configured through I2C interface before
> +  PCIe link is established to change FTS, ASPM related entry delays,
> +  tx amplitude etc for better power efficiency and functionality.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - pci1179,0623
> +
> +  reg:
> +    maxItems: 1
> +
> +  i2c-parent:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    description: |

Don't need '|' if no formatting to preserve.

> +      A phandle to the parent I2C node and the slave address of the device
> +      used to do configure qps615 to change FTS, tx amplitude etc.
> +    items:
> +      - description: Phandle to the I2C controller node
> +      - description: I2C slave address
> +
> +  vdd18-supply: true
> +
> +  vdd09-supply: true
> +
> +  vddc-supply: true
> +
> +  vddio1-supply: true
> +
> +  vddio2-supply: true
> +
> +  vddio18-supply: true
> +
> +  reset-gpios:
> +    maxItems: 1
> +    description:
> +      GPIO controlling the RESX# pin.

Is the PERST# or something else?

> +
> +  qps615,axi-clk-freq-hz:

qps615 is not a vendor prefix.

> +    description:
> +      AXI clock rate which is internal bus of the switch
> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
> +    enum: [125000000, 250000000]
> +
> +allOf:
> +  - $ref: "#/$defs/qps615-node"
> +
> +patternProperties:
> +  "@1?[0-9a-f](,[0-7])?$":

You have 3 ports. So isn't this fixed and limited to 0-2?

> +    description: child nodes describing the internal downstream ports
> +      the qps615 switch.

Please be consistent with starting after the ':' or on the next line.

And start with capital C.


> +    type: object
> +    $ref: "#/$defs/qps615-node"
> +    unevaluatedProperties: false
> +
> +$defs:
> +  qps615-node:
> +    type: object
> +
> +    properties:
> +      qcom,l0s-entry-delay-ns:
> +        description: Aspm l0s entry delay.
> +
> +      qcom,l1-entry-delay-ns:
> +        description: Aspm l1 entry delay.

These should probably be common being standard PCIe things. Though, why 
are they needed? I'm sure the timing is defined by the PCIe spec, so 
they are not compliant?

> +
> +      qcom,tx-amplitude-millivolt:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Change Tx Margin setting for low power consumption.
> +
> +      qcom,no-dfe-support:
> +        type: boolean
> +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
> +          intersymbol interference and some reflections caused by impedance mismatches.
> +
> +      qcom,nfts:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
> +          for bit and Symbol lock.

Also something common.

The problem I have with all these properties is you are using them on 
both the upstream and downstream sides of the PCIe links. They belong in 
either the device's node (downstream) or the bus's node (upstream). 

> +
> +    allOf:
> +      - $ref: /schemas/pci/pci-bus.yaml#

pci-pci-bridge.yaml is more specific and closer to what this device is.

> +
> +unevaluatedProperties: false
> +
> +required:
> +  - vdd18-supply
> +  - vdd09-supply
> +  - vddc-supply
> +  - vddio1-supply
> +  - vddio2-supply
> +  - vddio18-supply
> +  - i2c-parent
> +  - reset-gpios
> +
> +examples:
> +  - |
> +
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    pcie {
> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +
> +        pcie@0 {
> +            device_type = "pci";
> +            reg = <0x0 0x0 0x0 0x0 0x0>;
> +
> +            #address-cells = <3>;
> +            #size-cells = <2>;
> +            ranges;
> +            bus-range = <0x01 0xff>;
> +
> +            pcie@0,0 {
> +                compatible = "pci1179,0623";
> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
> +                device_type = "pci";
> +                #address-cells = <3>;
> +                #size-cells = <2>;
> +                ranges;
> +                bus-range = <0x02 0xff>;
> +
> +                i2c-parent = <&qup_i2c 0x77>;
> +
> +                vdd18-supply = <&vdd>;
> +                vdd09-supply = <&vdd>;
> +                vddc-supply = <&vdd>;
> +                vddio1-supply = <&vdd>;
> +                vddio2-supply = <&vdd>;
> +                vddio18-supply = <&vdd>;
> +
> +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
> +
> +                pcie@1,0 {
> +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x03 0xff>;
> +
> +                    qcom,no-dfe-support;
> +                };
> +
> +                pcie@2,0 {
> +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x04 0xff>;
> +
> +                    qcom,nfts = <10>;
> +                };
> +
> +                pcie@3,0 {
> +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
> +                    #address-cells = <3>;
> +                    #size-cells = <2>;
> +                    device_type = "pci";
> +                    ranges;
> +                    bus-range = <0x05 0xff>;
> +
> +                    qcom,tx-amplitude-millivolt = <10>;
> +                    pcie@0,0 {
> +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
> +                        #address-cells = <3>;
> +                        #size-cells = <2>;
> +                        device_type = "pci";

There's a 2nd PCI-PCI bridge?

> +                        ranges;
> +
> +                        qcom,l1-entry-delay-ns = <10>;
> +                    };
> +
> +                    pcie@0,1 {
> +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
> +                        #address-cells = <3>;
> +                        #size-cells = <2>;
> +                        device_type = "pci";
> +                        ranges;
> +
> +                        qcom,l0s-entry-delay-ns = <10>;
> +                    };
> +                };
> +            };
> +        };
> +    };
> 
> -- 
> 2.34.1
>
Krzysztof Kozlowski Nov. 20, 2024, 8:04 a.m. UTC | #3
On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> Add binding describing the Qualcomm PCIe switch, QPS615,
> which provides Ethernet MAC integrated to the 3rd downstream port
> and two downstream PCIe ports.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
>  1 file changed, 205 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> new file mode 100644
> index 000000000000..e6a63a0bb0f3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml

Isn't "qcom,qps615" a SoC name? This is supposed to be matching
compatible, in your case probably qcom,qps615-whatever-this-is?

...

> +  qps615,axi-clk-freq-hz:

That's a downstream code you send us.

Anyway, why assigned clock rates do not work for you? You are
re-implementing legacy property now under different name :/


> +    description:
> +      AXI clock rate which is internal bus of the switch
> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
> +    enum: [125000000, 250000000]
> +
> +allOf:
> +  - $ref: "#/$defs/qps615-node"
> +
> +patternProperties:
> +  "@1?[0-9a-f](,[0-7])?$":
> +    description: child nodes describing the internal downstream ports
> +      the qps615 switch.
> +    type: object
> +    $ref: "#/$defs/qps615-node"
> +    unevaluatedProperties: false
> +
> +$defs:
> +  qps615-node:
> +    type: object
> +
> +    properties:
> +      qcom,l0s-entry-delay-ns:
> +        description: Aspm l0s entry delay.
> +
> +      qcom,l1-entry-delay-ns:
> +        description: Aspm l1 entry delay.
> +
> +      qcom,tx-amplitude-millivolt:

-microvolt does not work for you?

> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Change Tx Margin setting for low power consumption.
> +
> +      qcom,no-dfe-support:
> +        type: boolean
> +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
> +          intersymbol interference and some reflections caused by impedance mismatches.
> +
> +      qcom,nfts:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
> +          for bit and Symbol lock.

Use some of these properties in the example. I saw only one.

> +
> +    allOf:
> +      - $ref: /schemas/pci/pci-bus.yaml#
> +
> +unevaluatedProperties: false
> +
> +required:
> +  - vdd18-supply
> +  - vdd09-supply
> +  - vddc-supply
> +  - vddio1-supply
> +  - vddio2-supply
> +  - vddio18-supply
> +  - i2c-parent
> +  - reset-gpios
> +
> +examples:
> +  - |
> +

Drop blank line

> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    pcie {
> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +
> +        pcie@0 {
> +            device_type = "pci";
> +            reg = <0x0 0x0 0x0 0x0 0x0>;

Best regards,
Krzysztof
Krishna Chaitanya Chundru Nov. 24, 2024, 1:32 a.m. UTC | #4
On 11/15/2024 9:48 PM, Rob Herring wrote:
> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
>> Add binding describing the Qualcomm PCIe switch, QPS615,
>> which provides Ethernet MAC integrated to the 3rd downstream port
>> and two downstream PCIe ports.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
>>   1 file changed, 205 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>> new file mode 100644
>> index 000000000000..e6a63a0bb0f3
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>> @@ -0,0 +1,205 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Qualcomm QPS615 PCIe switch
>> +
>> +maintainers:
>> +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> +
>> +description: |
>> +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
>> +  ports. The 3rd downstream port has integrated endpoint device of
>> +  Ethernet MAC. Other two downstream ports are supposed to connect
>> +  to external device.
>> +
>> +  The QPS615 PCIe switch can be configured through I2C interface before
>> +  PCIe link is established to change FTS, ASPM related entry delays,
>> +  tx amplitude etc for better power efficiency and functionality.
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - pci1179,0623
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  i2c-parent:
>> +    $ref: /schemas/types.yaml#/definitions/phandle-array
>> +    description: |
> 
> Don't need '|' if no formatting to preserve.
> 
ack
>> +      A phandle to the parent I2C node and the slave address of the device
>> +      used to do configure qps615 to change FTS, tx amplitude etc.
>> +    items:
>> +      - description: Phandle to the I2C controller node
>> +      - description: I2C slave address
>> +
>> +  vdd18-supply: true
>> +
>> +  vdd09-supply: true
>> +
>> +  vddc-supply: true
>> +
>> +  vddio1-supply: true
>> +
>> +  vddio2-supply: true
>> +
>> +  vddio18-supply: true
>> +
>> +  reset-gpios:
>> +    maxItems: 1
>> +    description:
>> +      GPIO controlling the RESX# pin.
> 
> Is the PERST# or something else?
> 
it is not PERST GPIO, it is similar to PERST in terms
of functionality which brings switch out from reset.
>> +
>> +  qps615,axi-clk-freq-hz:
> 
> qps615 is not a vendor prefix.
> 
>> +    description:
>> +      AXI clock rate which is internal bus of the switch
>> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
>> +    enum: [125000000, 250000000]
>> +
>> +allOf:
>> +  - $ref: "#/$defs/qps615-node"
>> +
>> +patternProperties:
>> +  "@1?[0-9a-f](,[0-7])?$":
> 
> You have 3 ports. So isn't this fixed and limited to 0-2?
> 
sure I will change it to below as suggested
"@1?[0-3](,[0-1])?$"
>> +    description: child nodes describing the internal downstream ports
>> +      the qps615 switch.
> 
> Please be consistent with starting after the ':' or on the next line.
> 
> And start with capital C.
> 
>
ack

>> +    type: object
>> +    $ref: "#/$defs/qps615-node"
>> +    unevaluatedProperties: false
>> +
>> +$defs:
>> +  qps615-node:
>> +    type: object
>> +
>> +    properties:
>> +      qcom,l0s-entry-delay-ns:
>> +        description: Aspm l0s entry delay.
>> +
>> +      qcom,l1-entry-delay-ns:
>> +        description: Aspm l1 entry delay.
> 
> These should probably be common being standard PCIe things. Though, why
> are they needed? I'm sure the timing is defined by the PCIe spec, so
> they are not compliant?
> 
Usually the firmware in the endpoints/switches should do this these
configurations. But the qps615 PCIe switch doesn't have any firmware
running to configure these. So the hardware exposes i2c interface to
configure these before link training.
>> +
>> +      qcom,tx-amplitude-millivolt:
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description: Change Tx Margin setting for low power consumption.
>> +
>> +      qcom,no-dfe-support:
>> +        type: boolean
>> +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
>> +          intersymbol interference and some reflections caused by impedance mismatches.
>> +
>> +      qcom,nfts:
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description:
>> +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
>> +          for bit and Symbol lock.
> 
> Also something common.
> 
> The problem I have with all these properties is you are using them on
> both the upstream and downstream sides of the PCIe links. They belong in
> either the device's node (downstream) or the bus's node (upstream).
> 
This switch allows us to configure both upstream, downstream ports and
also embedded Ethernet port which is internal to the switch. These
properties are applicable for all of those.
>> +
>> +    allOf:
>> +      - $ref: /schemas/pci/pci-bus.yaml#
> 
> pci-pci-bridge.yaml is more specific and closer to what this device is.
> 
I tried this now, I was getting warning saying the compatible
/local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: 
pcie@0,0: compatible: ['pci1179,0623'] does not contain items matching 
the given schema
         from schema $id: 
http://devicetree.org/schemas/pci/qcom,qps615.yaml#
/local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: 
pcie@0,0: Unevaluated properties are not allowed ('#address-cells', 
'#size-cells', 'bus-range', 'device_type', 'ranges' were unexpected)

I think pci-pci-bridge is expecting the compatible string in this format
only "pciclass,0604".

>> +
>> +unevaluatedProperties: false
>> +
>> +required:
>> +  - vdd18-supply
>> +  - vdd09-supply
>> +  - vddc-supply
>> +  - vddio1-supply
>> +  - vddio2-supply
>> +  - vddio18-supply
>> +  - i2c-parent
>> +  - reset-gpios
>> +
>> +examples:
>> +  - |
>> +
>> +    #include <dt-bindings/gpio/gpio.h>
>> +
>> +    pcie {
>> +        #address-cells = <3>;
>> +        #size-cells = <2>;
>> +
>> +        pcie@0 {
>> +            device_type = "pci";
>> +            reg = <0x0 0x0 0x0 0x0 0x0>;
>> +
>> +            #address-cells = <3>;
>> +            #size-cells = <2>;
>> +            ranges;
>> +            bus-range = <0x01 0xff>;
>> +
>> +            pcie@0,0 {
>> +                compatible = "pci1179,0623";
>> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
>> +                device_type = "pci";
>> +                #address-cells = <3>;
>> +                #size-cells = <2>;
>> +                ranges;
>> +                bus-range = <0x02 0xff>;
>> +
>> +                i2c-parent = <&qup_i2c 0x77>;
>> +
>> +                vdd18-supply = <&vdd>;
>> +                vdd09-supply = <&vdd>;
>> +                vddc-supply = <&vdd>;
>> +                vddio1-supply = <&vdd>;
>> +                vddio2-supply = <&vdd>;
>> +                vddio18-supply = <&vdd>;
>> +
>> +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
>> +
>> +                pcie@1,0 {
>> +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
>> +                    #address-cells = <3>;
>> +                    #size-cells = <2>;
>> +                    device_type = "pci";
>> +                    ranges;
>> +                    bus-range = <0x03 0xff>;
>> +
>> +                    qcom,no-dfe-support;
>> +                };
>> +
>> +                pcie@2,0 {
>> +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
>> +                    #address-cells = <3>;
>> +                    #size-cells = <2>;
>> +                    device_type = "pci";
>> +                    ranges;
>> +                    bus-range = <0x04 0xff>;
>> +
>> +                    qcom,nfts = <10>;
>> +                };
>> +
>> +                pcie@3,0 {
>> +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
>> +                    #address-cells = <3>;
>> +                    #size-cells = <2>;
>> +                    device_type = "pci";
>> +                    ranges;
>> +                    bus-range = <0x05 0xff>;
>> +
>> +                    qcom,tx-amplitude-millivolt = <10>;
>> +                    pcie@0,0 {
>> +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
>> +                        #address-cells = <3>;
>> +                        #size-cells = <2>;
>> +                        device_type = "pci";
> 
> There's a 2nd PCI-PCI bridge?
This the embedded ethernet port which is as part of DSP3.

- Krishna Chaitanya.
> 
>> +                        ranges;
>> +
>> +                        qcom,l1-entry-delay-ns = <10>;
>> +                    };
>> +
>> +                    pcie@0,1 {
>> +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
>> +                        #address-cells = <3>;
>> +                        #size-cells = <2>;
>> +                        device_type = "pci";
>> +                        ranges;
>> +
>> +                        qcom,l0s-entry-delay-ns = <10>;
>> +                    };
>> +                };
>> +            };
>> +        };
>> +    };
>>
>> -- 
>> 2.34.1
>>
Krishna Chaitanya Chundru Nov. 24, 2024, 1:41 a.m. UTC | #5
On 11/20/2024 1:34 PM, Krzysztof Kozlowski wrote:
> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
>> Add binding describing the Qualcomm PCIe switch, QPS615,
>> which provides Ethernet MAC integrated to the 3rd downstream port
>> and two downstream PCIe ports.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
>>   1 file changed, 205 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>> new file mode 100644
>> index 000000000000..e6a63a0bb0f3
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> 
> Isn't "qcom,qps615" a SoC name? This is supposed to be matching
> compatible, in your case probably qcom,qps615-whatever-this-is?
>
qcom,qcs615 is a soc name, qcom,qps615 is the pcie switch.

ack I will change it to qcom,qps615-pcie

> ...
> 
>> +  qps615,axi-clk-freq-hz:
> 
> That's a downstream code you send us.
> 
> Anyway, why assigned clock rates do not work for you? You are
> re-implementing legacy property now under different name :/
> 
> The assigned clock rates comes in to the picture when we are using clock
framework to control the clocks. For this switch there are no clocks 
needs to be control, the moment we power on the switch clocks are
enabled by default. This switch provides a mechanism to control the
frequency using i2c. And switch supports only two frequencies i.e
125MHz and 250MHZ by default it runs on 250MHz, we can do one i2c
write with which switch runs in 125MHz.
>> +    description:
>> +      AXI clock rate which is internal bus of the switch
>> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
>> +    enum: [125000000, 250000000]
>> +
>> +allOf:
>> +  - $ref: "#/$defs/qps615-node"
>> +
>> +patternProperties:
>> +  "@1?[0-9a-f](,[0-7])?$":
>> +    description: child nodes describing the internal downstream ports
>> +      the qps615 switch.
>> +    type: object
>> +    $ref: "#/$defs/qps615-node"
>> +    unevaluatedProperties: false
>> +
>> +$defs:
>> +  qps615-node:
>> +    type: object
>> +
>> +    properties:
>> +      qcom,l0s-entry-delay-ns:
>> +        description: Aspm l0s entry delay.
>> +
>> +      qcom,l1-entry-delay-ns:
>> +        description: Aspm l1 entry delay.
>> +
>> +      qcom,tx-amplitude-millivolt:
> 
> -microvolt does not work for you?
> 
let me check this if it is applicable we will change it to microvolt.
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description: Change Tx Margin setting for low power consumption.
>> +
>> +      qcom,no-dfe-support:
>> +        type: boolean
>> +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
>> +          intersymbol interference and some reflections caused by impedance mismatches.
>> +
>> +      qcom,nfts:
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description:
>> +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
>> +          for bit and Symbol lock.
> 
> Use some of these properties in the example. I saw only one.
> 
In the next patch I will try to use all the properties as suggested.
>> +
>> +    allOf:
>> +      - $ref: /schemas/pci/pci-bus.yaml#
>> +
>> +unevaluatedProperties: false
>> +
>> +required:
>> +  - vdd18-supply
>> +  - vdd09-supply
>> +  - vddc-supply
>> +  - vddio1-supply
>> +  - vddio2-supply
>> +  - vddio18-supply
>> +  - i2c-parent
>> +  - reset-gpios
>> +
>> +examples:
>> +  - |
>> +
> 
> Drop blank line
> 
ack.

- Krishna Chaitanya.
>> +    #include <dt-bindings/gpio/gpio.h>
>> +
>> +    pcie {
>> +        #address-cells = <3>;
>> +        #size-cells = <2>;
>> +
>> +        pcie@0 {
>> +            device_type = "pci";
>> +            reg = <0x0 0x0 0x0 0x0 0x0>;
> 
> Best regards,
> Krzysztof
>
Krzysztof Kozlowski Nov. 25, 2024, 7:40 a.m. UTC | #6
On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
>> ...
>>
>>> +  qps615,axi-clk-freq-hz:
>>
>> That's a downstream code you send us.
>>
>> Anyway, why assigned clock rates do not work for you? You are
>> re-implementing legacy property now under different name :/
>>
>> The assigned clock rates comes in to the picture when we are using clock
> framework to control the clocks. For this switch there are no clocks 
> needs to be control, the moment we power on the switch clocks are
> enabled by default. This switch provides a mechanism to control the
> frequency using i2c. And switch supports only two frequencies i.e


frequency of what, since there are no clocks?

> 125MHz and 250MHZ by default it runs on 250MHz, we can do one i2c
> write with which switch runs in 125MHz.

How doing a write is relevant? Or you want to say you can control clock?



Best regards,
Krzysztof
Krishna Chaitanya Chundru Nov. 26, 2024, 6:50 a.m. UTC | #7
On 11/25/2024 1:10 PM, Krzysztof Kozlowski wrote:
> On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
>>> ...
>>> 
>>>> +  qps615,axi-clk-freq-hz:
>>> 
>>> That's a downstream code you send us.
>>> 
>>> Anyway, why assigned clock rates do not work for you? You are 
>>> re-implementing legacy property now under different name :/
>>> 
>>> The assigned clock rates comes in to the picture when we are 
>>> using clock
>> framework to control the clocks. For this switch there are no 
>> clocks needs to be control, the moment we power on the switch 
>> clocks are enabled by default. This switch provides a mechanism to 
>> control the frequency using i2c. And switch supports only two 
>> frequencies i.e
> 
> 
> frequency of what, since there are no clocks?
> 
The axi clock frequency internal to the switch, host can't control
the enablement of the clocks it can control only the frequency.

we already had a discussion on this on v2[1], and we taught you agreed
on this property.

[1] 
https://lore.kernel.org/netdev/d1af1eac-f9bd-7a8e-586b-5c2a76445145@codeaurora.org/T/#m3d5864c758f2e05fa15ba522aad6a37e3417bd9f

- Krishna Chaitanya.
>> 125MHz and 250MHZ by default it runs on 250MHz, we can do one i2c 
>> write with which switch runs in 125MHz.
> 
> How doing a write is relevant? Or you want to say you can control 
> clock?
> 
> 
> 
> Best regards, Krzysztof
Krzysztof Kozlowski Nov. 26, 2024, 6:58 a.m. UTC | #8
On 26/11/2024 07:50, Krishna Chaitanya Chundru wrote:
> 
> 
> On 11/25/2024 1:10 PM, Krzysztof Kozlowski wrote:
>> On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
>>>> ...
>>>>
>>>>> +  qps615,axi-clk-freq-hz:
>>>>
>>>> That's a downstream code you send us.
>>>>
>>>> Anyway, why assigned clock rates do not work for you? You are 
>>>> re-implementing legacy property now under different name :/
>>>>
>>>> The assigned clock rates comes in to the picture when we are 
>>>> using clock
>>> framework to control the clocks. For this switch there are no 
>>> clocks needs to be control, the moment we power on the switch 
>>> clocks are enabled by default. This switch provides a mechanism to 
>>> control the frequency using i2c. And switch supports only two 
>>> frequencies i.e
>>
>>
>> frequency of what, since there are no clocks?
>>
> The axi clock frequency internal to the switch, host can't control
> the enablement of the clocks it can control only the frequency.
> 
> we already had a discussion on this on v2[1], and we taught you agreed
> on this property.
> 
> [1] 
> https://lore.kernel.org/netdev/d1af1eac-f9bd-7a8e-586b-5c2a76445145@codeaurora.org/T/#m3d5864c758f2e05fa15ba522aad6a37e3417bd9f
> 

This points something else. I diged v2 and found many unanswered
questions and unfinished discussion:

https://lore.kernel.org/r/linux-arm-msm/20240803-qps615-v2-0-9560b7c71369@quicinc.com/T/#m7074ab9e5f89e29faf430c82f769e67d0e4072cf

The property description did not improve, actually it got worse: you
repeat constraints in free form text.

Best regards,
Krzysztof
Manivannan Sadhasivam Nov. 28, 2024, 1:24 p.m. UTC | #9
On Tue, Nov 26, 2024 at 07:58:16AM +0100, Krzysztof Kozlowski wrote:
> On 26/11/2024 07:50, Krishna Chaitanya Chundru wrote:
> > 
> > 
> > On 11/25/2024 1:10 PM, Krzysztof Kozlowski wrote:
> >> On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
> >>>> ...
> >>>>
> >>>>> +  qps615,axi-clk-freq-hz:
> >>>>
> >>>> That's a downstream code you send us.
> >>>>
> >>>> Anyway, why assigned clock rates do not work for you? You are 
> >>>> re-implementing legacy property now under different name :/
> >>>>
> >>>> The assigned clock rates comes in to the picture when we are 
> >>>> using clock
> >>> framework to control the clocks. For this switch there are no 
> >>> clocks needs to be control, the moment we power on the switch 
> >>> clocks are enabled by default. This switch provides a mechanism to 
> >>> control the frequency using i2c. And switch supports only two 
> >>> frequencies i.e
> >>
> >>
> >> frequency of what, since there are no clocks?
> >>
> > The axi clock frequency internal to the switch, host can't control
> > the enablement of the clocks it can control only the frequency.
> > 
> > we already had a discussion on this on v2[1], and we taught you agreed
> > on this property.
> > 
> > [1] 
> > https://lore.kernel.org/netdev/d1af1eac-f9bd-7a8e-586b-5c2a76445145@codeaurora.org/T/#m3d5864c758f2e05fa15ba522aad6a37e3417bd9f
> > 
> 
> This points something else. I diged v2 and found many unanswered
> questions and unfinished discussion:
> 

The conversation is here:
https://lore.kernel.org/linux-arm-msm/20240823094028.7xul4eoiexey5xjm@thinkpad/

But there was no explicit agreement on the usage of 'qps615,axi-clk-freq-hz'.

If describing the PCI device's internal clock frequency is not applicable, then
I'd recommend to change the clock rate in the driver itself based on the number
of DSPs enabled (or based on other configuration).

- Mani
Dmitry Baryshkov Nov. 28, 2024, 2:08 p.m. UTC | #10
On Thu, Nov 28, 2024 at 06:54:32PM +0530, Manivannan Sadhasivam wrote:
> On Tue, Nov 26, 2024 at 07:58:16AM +0100, Krzysztof Kozlowski wrote:
> > On 26/11/2024 07:50, Krishna Chaitanya Chundru wrote:
> > > 
> > > 
> > > On 11/25/2024 1:10 PM, Krzysztof Kozlowski wrote:
> > >> On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
> > >>>> ...
> > >>>>
> > >>>>> +  qps615,axi-clk-freq-hz:
> > >>>>
> > >>>> That's a downstream code you send us.
> > >>>>
> > >>>> Anyway, why assigned clock rates do not work for you? You are 
> > >>>> re-implementing legacy property now under different name :/
> > >>>>
> > >>>> The assigned clock rates comes in to the picture when we are 
> > >>>> using clock
> > >>> framework to control the clocks. For this switch there are no 
> > >>> clocks needs to be control, the moment we power on the switch 
> > >>> clocks are enabled by default. This switch provides a mechanism to 
> > >>> control the frequency using i2c. And switch supports only two 
> > >>> frequencies i.e
> > >>
> > >>
> > >> frequency of what, since there are no clocks?
> > >>
> > > The axi clock frequency internal to the switch, host can't control
> > > the enablement of the clocks it can control only the frequency.
> > > 
> > > we already had a discussion on this on v2[1], and we taught you agreed
> > > on this property.
> > > 
> > > [1] 
> > > https://lore.kernel.org/netdev/d1af1eac-f9bd-7a8e-586b-5c2a76445145@codeaurora.org/T/#m3d5864c758f2e05fa15ba522aad6a37e3417bd9f
> > > 
> > 
> > This points something else. I diged v2 and found many unanswered
> > questions and unfinished discussion:
> > 
> 
> The conversation is here:
> https://lore.kernel.org/linux-arm-msm/20240823094028.7xul4eoiexey5xjm@thinkpad/
> 
> But there was no explicit agreement on the usage of 'qps615,axi-clk-freq-hz'.
> 
> If describing the PCI device's internal clock frequency is not applicable, then
> I'd recommend to change the clock rate in the driver itself based on the number
> of DSPs enabled (or based on other configuration).

Sounds like the best approach. Otherwise it's not obvious, what is the
criteria for selecting this or that clock value.

> 
> - Mani
> 
> -- 
> மணிவண்ணன் சதாசிவம்
Krishna Chaitanya Chundru Dec. 3, 2024, 9:06 a.m. UTC | #11
On 11/28/2024 7:38 PM, Dmitry Baryshkov wrote:
> On Thu, Nov 28, 2024 at 06:54:32PM +0530, Manivannan Sadhasivam wrote:
>> On Tue, Nov 26, 2024 at 07:58:16AM +0100, Krzysztof Kozlowski wrote:
>>> On 26/11/2024 07:50, Krishna Chaitanya Chundru wrote:
>>>>
>>>>
>>>> On 11/25/2024 1:10 PM, Krzysztof Kozlowski wrote:
>>>>> On 24/11/2024 02:41, Krishna Chaitanya Chundru wrote:
>>>>>>> ...
>>>>>>>
>>>>>>>> +  qps615,axi-clk-freq-hz:
>>>>>>>
>>>>>>> That's a downstream code you send us.
>>>>>>>
>>>>>>> Anyway, why assigned clock rates do not work for you? You are
>>>>>>> re-implementing legacy property now under different name :/
>>>>>>>
>>>>>>> The assigned clock rates comes in to the picture when we are
>>>>>>> using clock
>>>>>> framework to control the clocks. For this switch there are no
>>>>>> clocks needs to be control, the moment we power on the switch
>>>>>> clocks are enabled by default. This switch provides a mechanism to
>>>>>> control the frequency using i2c. And switch supports only two
>>>>>> frequencies i.e
>>>>>
>>>>>
>>>>> frequency of what, since there are no clocks?
>>>>>
>>>> The axi clock frequency internal to the switch, host can't control
>>>> the enablement of the clocks it can control only the frequency.
>>>>
>>>> we already had a discussion on this on v2[1], and we taught you agreed
>>>> on this property.
>>>>
>>>> [1]
>>>> https://lore.kernel.org/netdev/d1af1eac-f9bd-7a8e-586b-5c2a76445145@codeaurora.org/T/#m3d5864c758f2e05fa15ba522aad6a37e3417bd9f
>>>>
>>>
>>> This points something else. I diged v2 and found many unanswered
>>> questions and unfinished discussion:
>>>
>>
>> The conversation is here:
>> https://lore.kernel.org/linux-arm-msm/20240823094028.7xul4eoiexey5xjm@thinkpad/
>>
>> But there was no explicit agreement on the usage of 'qps615,axi-clk-freq-hz'.
>>
>> If describing the PCI device's internal clock frequency is not applicable, then
>> I'd recommend to change the clock rate in the driver itself based on the number
>> of DSPs enabled (or based on other configuration).
> 
> Sounds like the best approach. Otherwise it's not obvious, what is the
> criteria for selecting this or that clock value.
> 
I will remove this property in next patch and driver code to set this 
frequency in the next patch, we will try to come up with some logic later.

- Krishna chaitanya.
>>
>> - Mani
>>
>> -- 
>> மணிவண்ணன் சதாசிவம்
>
Krishna Chaitanya Chundru Dec. 4, 2024, 8:49 a.m. UTC | #12
On 11/24/2024 7:02 AM, Krishna Chaitanya Chundru wrote:
> 
> 
> On 11/15/2024 9:48 PM, Rob Herring wrote:
>> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru 
>> wrote:
>>> Add binding describing the Qualcomm PCIe switch, QPS615,
>>> which provides Ethernet MAC integrated to the 3rd downstream port
>>> and two downstream PCIe ports.
>>>
>>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>>> ---
>>>   .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 
>>> +++++++++++++++++++++
>>>   1 file changed, 205 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml 
>>> b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>>> new file mode 100644
>>> index 000000000000..e6a63a0bb0f3
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>>> @@ -0,0 +1,205 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Qualcomm QPS615 PCIe switch
>>> +
>>> +maintainers:
>>> +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
>>> +
>>> +description: |
>>> +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
>>> +  ports. The 3rd downstream port has integrated endpoint device of
>>> +  Ethernet MAC. Other two downstream ports are supposed to connect
>>> +  to external device.
>>> +
>>> +  The QPS615 PCIe switch can be configured through I2C interface before
>>> +  PCIe link is established to change FTS, ASPM related entry delays,
>>> +  tx amplitude etc for better power efficiency and functionality.
>>> +
>>> +properties:
>>> +  compatible:
>>> +    enum:
>>> +      - pci1179,0623
>>> +
>>> +  reg:
>>> +    maxItems: 1
>>> +
>>> +  i2c-parent:
>>> +    $ref: /schemas/types.yaml#/definitions/phandle-array
>>> +    description: |
>>
>> Don't need '|' if no formatting to preserve.
>>
> ack
>>> +      A phandle to the parent I2C node and the slave address of the 
>>> device
>>> +      used to do configure qps615 to change FTS, tx amplitude etc.
>>> +    items:
>>> +      - description: Phandle to the I2C controller node
>>> +      - description: I2C slave address
>>> +
>>> +  vdd18-supply: true
>>> +
>>> +  vdd09-supply: true
>>> +
>>> +  vddc-supply: true
>>> +
>>> +  vddio1-supply: true
>>> +
>>> +  vddio2-supply: true
>>> +
>>> +  vddio18-supply: true
>>> +
>>> +  reset-gpios:
>>> +    maxItems: 1
>>> +    description:
>>> +      GPIO controlling the RESX# pin.
>>
>> Is the PERST# or something else?
>>
> it is not PERST GPIO, it is similar to PERST in terms
> of functionality which brings switch out from reset.
>>> +
>>> +  qps615,axi-clk-freq-hz:
>>
>> qps615 is not a vendor prefix.
>>
>>> +    description:
>>> +      AXI clock rate which is internal bus of the switch
>>> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
>>> +    enum: [125000000, 250000000]
>>> +
>>> +allOf:
>>> +  - $ref: "#/$defs/qps615-node"
>>> +
>>> +patternProperties:
>>> +  "@1?[0-9a-f](,[0-7])?$":
>>
>> You have 3 ports. So isn't this fixed and limited to 0-2?
>>
> sure I will change it to below as suggested
> "@1?[0-3](,[0-1])?$"
>>> +    description: child nodes describing the internal downstream ports
>>> +      the qps615 switch.
>>
>> Please be consistent with starting after the ':' or on the next line.
>>
>> And start with capital C.
>>
>>
> ack
> 
>>> +    type: object
>>> +    $ref: "#/$defs/qps615-node"
>>> +    unevaluatedProperties: false
>>> +
>>> +$defs:
>>> +  qps615-node:
>>> +    type: object
>>> +
>>> +    properties:
>>> +      qcom,l0s-entry-delay-ns:
>>> +        description: Aspm l0s entry delay.
>>> +
>>> +      qcom,l1-entry-delay-ns:
>>> +        description: Aspm l1 entry delay.
>>
>> These should probably be common being standard PCIe things. Though, why
>> are they needed? I'm sure the timing is defined by the PCIe spec, so
>> they are not compliant?
>>
> Usually the firmware in the endpoints/switches should do this these
> configurations. But the qps615 PCIe switch doesn't have any firmware
> running to configure these. So the hardware exposes i2c interface to
> configure these before link training.
>>> +
>>> +      qcom,tx-amplitude-millivolt:
>>> +        $ref: /schemas/types.yaml#/definitions/uint32
>>> +        description: Change Tx Margin setting for low power 
>>> consumption.
>>> +
>>> +      qcom,no-dfe-support:
>>> +        type: boolean
>>> +        description: Disable DFE (Decision Feedback Equalizer), 
>>> which mitigates
>>> +          intersymbol interference and some reflections caused by 
>>> impedance mismatches.
>>> +
>>> +      qcom,nfts:
>>> +        $ref: /schemas/types.yaml#/definitions/uint32
>>> +        description:
>>> +          Number of Fast Training Sequence (FTS) used during L0s to 
>>> L0 exit
>>> +          for bit and Symbol lock.
>>
>> Also something common.
>>
>> The problem I have with all these properties is you are using them on
>> both the upstream and downstream sides of the PCIe links. They belong in
>> either the device's node (downstream) or the bus's node (upstream).
>>
> This switch allows us to configure both upstream, downstream ports and
> also embedded Ethernet port which is internal to the switch. These
> properties are applicable for all of those.
>>> +
>>> +    allOf:
>>> +      - $ref: /schemas/pci/pci-bus.yaml#
>>
>> pci-pci-bridge.yaml is more specific and closer to what this device is.
>>
> I tried this now, I was getting warning saying the compatible
> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: pcie@0,0: compatible: ['pci1179,0623'] does not contain items matching the given schema
>          from schema $id: 
> http://devicetree.org/schemas/pci/qcom,qps615.yaml#
> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: pcie@0,0: Unevaluated properties are not allowed ('#address-cells', '#size-cells', 'bus-range', 'device_type', 'ranges' were unexpected)
> 
> I think pci-pci-bridge is expecting the compatible string in this format
> only "pciclass,0604".
> 
>>> +
>>> +unevaluatedProperties: false
>>> +
>>> +required:
>>> +  - vdd18-supply
>>> +  - vdd09-supply
>>> +  - vddc-supply
>>> +  - vddio1-supply
>>> +  - vddio2-supply
>>> +  - vddio18-supply
>>> +  - i2c-parent
>>> +  - reset-gpios
>>> +
>>> +examples:
>>> +  - |
>>> +
>>> +    #include <dt-bindings/gpio/gpio.h>
>>> +
>>> +    pcie {
>>> +        #address-cells = <3>;
>>> +        #size-cells = <2>;
>>> +
>>> +        pcie@0 {
>>> +            device_type = "pci";
>>> +            reg = <0x0 0x0 0x0 0x0 0x0>;
>>> +
>>> +            #address-cells = <3>;
>>> +            #size-cells = <2>;
>>> +            ranges;
>>> +            bus-range = <0x01 0xff>;
>>> +
>>> +            pcie@0,0 {
>>> +                compatible = "pci1179,0623";
>>> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
>>> +                device_type = "pci";
>>> +                #address-cells = <3>;
>>> +                #size-cells = <2>;
>>> +                ranges;
>>> +                bus-range = <0x02 0xff>;
>>> +
>>> +                i2c-parent = <&qup_i2c 0x77>;
>>> +
>>> +                vdd18-supply = <&vdd>;
>>> +                vdd09-supply = <&vdd>;
>>> +                vddc-supply = <&vdd>;
>>> +                vddio1-supply = <&vdd>;
>>> +                vddio2-supply = <&vdd>;
>>> +                vddio18-supply = <&vdd>;
>>> +
>>> +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
>>> +
>>> +                pcie@1,0 {
>>> +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
>>> +                    #address-cells = <3>;
>>> +                    #size-cells = <2>;
>>> +                    device_type = "pci";
>>> +                    ranges;
>>> +                    bus-range = <0x03 0xff>;
>>> +
>>> +                    qcom,no-dfe-support;
>>> +                };
>>> +
>>> +                pcie@2,0 {
>>> +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
>>> +                    #address-cells = <3>;
>>> +                    #size-cells = <2>;
>>> +                    device_type = "pci";
>>> +                    ranges;
>>> +                    bus-range = <0x04 0xff>;
>>> +
>>> +                    qcom,nfts = <10>;
>>> +                };
>>> +
>>> +                pcie@3,0 {
>>> +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
>>> +                    #address-cells = <3>;
>>> +                    #size-cells = <2>;
>>> +                    device_type = "pci";
>>> +                    ranges;
>>> +                    bus-range = <0x05 0xff>;
>>> +
>>> +                    qcom,tx-amplitude-millivolt = <10>;
>>> +                    pcie@0,0 {
>>> +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
>>> +                        #address-cells = <3>;
>>> +                        #size-cells = <2>;
>>> +                        device_type = "pci";
>>
>> There's a 2nd PCI-PCI bridge?
> This the embedded ethernet port which is as part of DSP3.
> 
Hi Rob,

Can you please check my response on your queries, if you need
any extra information, we can provide to sort this out.

- Krishna Chaitanya.
> - Krishna Chaitanya.
>>
>>> +                        ranges;
>>> +
>>> +                        qcom,l1-entry-delay-ns = <10>;
>>> +                    };
>>> +
>>> +                    pcie@0,1 {
>>> +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
>>> +                        #address-cells = <3>;
>>> +                        #size-cells = <2>;
>>> +                        device_type = "pci";
>>> +                        ranges;
>>> +
>>> +                        qcom,l0s-entry-delay-ns = <10>;
>>> +                    };
>>> +                };
>>> +            };
>>> +        };
>>> +    };
>>>
>>> -- 
>>> 2.34.1
>>>
>
Bjorn Helgaas Dec. 4, 2024, 9:25 p.m. UTC | #13
On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> Add binding describing the Qualcomm PCIe switch, QPS615,
> which provides Ethernet MAC integrated to the 3rd downstream port
> and two downstream PCIe ports.

> +$defs:
> +  qps615-node:
> +    type: object
> +
> +    properties:
> +      qcom,l0s-entry-delay-ns:
> +        description: Aspm l0s entry delay.
> +
> +      qcom,l1-entry-delay-ns:
> +        description: Aspm l1 entry delay.

To match spec usage:
s/Aspm/ASPM/
s/l0s/L0s/
s/l1/L1/

Other than the fact that qps615 needs the driver to configure these,
there's nothing qcom-specific here, so I suggest the names should omit
"qcom" and include "aspm".

> +    pcie {
> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +
> +        pcie@0 {
> +            device_type = "pci";
> +            reg = <0x0 0x0 0x0 0x0 0x0>;
> +
> +            #address-cells = <3>;
> +            #size-cells = <2>;
> +            ranges;
> +            bus-range = <0x01 0xff>;
> +
> +            pcie@0,0 {
> +                compatible = "pci1179,0623";
> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
> +                device_type = "pci";
> +                #address-cells = <3>;
> +                #size-cells = <2>;
> +                ranges;
> +                bus-range = <0x02 0xff>;

This binding describes a switch.  I don't think bus-range should
appear here at all because it is not a feature of the hardware (unless
the switch ports are broken and their Secondary/Subordinate Bus
Numbers are hard-wired).

The Primary/Secondary/Subordinate Bus Numbers of all switch ports
should be writable and the PCI core knows how to manage them.

Bjorn
Manivannan Sadhasivam Dec. 11, 2024, 6 a.m. UTC | #14
On Wed, Dec 04, 2024 at 03:25:59PM -0600, Bjorn Helgaas wrote:
> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> > Add binding describing the Qualcomm PCIe switch, QPS615,
> > which provides Ethernet MAC integrated to the 3rd downstream port
> > and two downstream PCIe ports.
> 
> > +$defs:
> > +  qps615-node:
> > +    type: object
> > +
> > +    properties:
> > +      qcom,l0s-entry-delay-ns:
> > +        description: Aspm l0s entry delay.
> > +
> > +      qcom,l1-entry-delay-ns:
> > +        description: Aspm l1 entry delay.
> 
> To match spec usage:
> s/Aspm/ASPM/
> s/l0s/L0s/
> s/l1/L1/
> 
> Other than the fact that qps615 needs the driver to configure these,
> there's nothing qcom-specific here, so I suggest the names should omit
> "qcom" and include "aspm".
> 

In that case, these properties should be documented in dt-schema:
https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/pci/pci-bus-common.yaml

- Mani
Krishna Chaitanya Chundru Dec. 23, 2024, 4:45 p.m. UTC | #15
On 12/4/2024 2:19 PM, Krishna Chaitanya Chundru wrote:
> 
> 
> On 11/24/2024 7:02 AM, Krishna Chaitanya Chundru wrote:
>>
>>
>> On 11/15/2024 9:48 PM, Rob Herring wrote:
>>> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru 
>>> wrote:
>>>> Add binding describing the Qualcomm PCIe switch, QPS615,
>>>> which provides Ethernet MAC integrated to the 3rd downstream port
>>>> and two downstream PCIe ports.
>>>>
>>>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>>>> ---
>>>>   .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 
>>>> +++++++++++++++++++++
>>>>   1 file changed, 205 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml 
>>>> b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>>>> new file mode 100644
>>>> index 000000000000..e6a63a0bb0f3
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
>>>> @@ -0,0 +1,205 @@
>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>> +%YAML 1.2
>>>> +---
>>>> +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>> +
>>>> +title: Qualcomm QPS615 PCIe switch
>>>> +
>>>> +maintainers:
>>>> +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
>>>> +
>>>> +description: |
>>>> +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
>>>> +  ports. The 3rd downstream port has integrated endpoint device of
>>>> +  Ethernet MAC. Other two downstream ports are supposed to connect
>>>> +  to external device.
>>>> +
>>>> +  The QPS615 PCIe switch can be configured through I2C interface 
>>>> before
>>>> +  PCIe link is established to change FTS, ASPM related entry delays,
>>>> +  tx amplitude etc for better power efficiency and functionality.
>>>> +
>>>> +properties:
>>>> +  compatible:
>>>> +    enum:
>>>> +      - pci1179,0623
>>>> +
>>>> +  reg:
>>>> +    maxItems: 1
>>>> +
>>>> +  i2c-parent:
>>>> +    $ref: /schemas/types.yaml#/definitions/phandle-array
>>>> +    description: |
>>>
>>> Don't need '|' if no formatting to preserve.
>>>
>> ack
>>>> +      A phandle to the parent I2C node and the slave address of the 
>>>> device
>>>> +      used to do configure qps615 to change FTS, tx amplitude etc.
>>>> +    items:
>>>> +      - description: Phandle to the I2C controller node
>>>> +      - description: I2C slave address
>>>> +
>>>> +  vdd18-supply: true
>>>> +
>>>> +  vdd09-supply: true
>>>> +
>>>> +  vddc-supply: true
>>>> +
>>>> +  vddio1-supply: true
>>>> +
>>>> +  vddio2-supply: true
>>>> +
>>>> +  vddio18-supply: true
>>>> +
>>>> +  reset-gpios:
>>>> +    maxItems: 1
>>>> +    description:
>>>> +      GPIO controlling the RESX# pin.
>>>
>>> Is the PERST# or something else?
>>>
>> it is not PERST GPIO, it is similar to PERST in terms
>> of functionality which brings switch out from reset.
>>>> +
>>>> +  qps615,axi-clk-freq-hz:
>>>
>>> qps615 is not a vendor prefix.
>>>
>>>> +    description:
>>>> +      AXI clock rate which is internal bus of the switch
>>>> +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
>>>> +    enum: [125000000, 250000000]
>>>> +
>>>> +allOf:
>>>> +  - $ref: "#/$defs/qps615-node"
>>>> +
>>>> +patternProperties:
>>>> +  "@1?[0-9a-f](,[0-7])?$":
>>>
>>> You have 3 ports. So isn't this fixed and limited to 0-2?
>>>
>> sure I will change it to below as suggested
>> "@1?[0-3](,[0-1])?$"
>>>> +    description: child nodes describing the internal downstream ports
>>>> +      the qps615 switch.
>>>
>>> Please be consistent with starting after the ':' or on the next line.
>>>
>>> And start with capital C.
>>>
>>>
>> ack
>>
>>>> +    type: object
>>>> +    $ref: "#/$defs/qps615-node"
>>>> +    unevaluatedProperties: false
>>>> +
>>>> +$defs:
>>>> +  qps615-node:
>>>> +    type: object
>>>> +
>>>> +    properties:
>>>> +      qcom,l0s-entry-delay-ns:
>>>> +        description: Aspm l0s entry delay.
>>>> +
>>>> +      qcom,l1-entry-delay-ns:
>>>> +        description: Aspm l1 entry delay.
>>>
>>> These should probably be common being standard PCIe things. Though, why
>>> are they needed? I'm sure the timing is defined by the PCIe spec, so
>>> they are not compliant?
>>>
>> Usually the firmware in the endpoints/switches should do this these
>> configurations. But the qps615 PCIe switch doesn't have any firmware
>> running to configure these. So the hardware exposes i2c interface to
>> configure these before link training.
>>>> +
>>>> +      qcom,tx-amplitude-millivolt:
>>>> +        $ref: /schemas/types.yaml#/definitions/uint32
>>>> +        description: Change Tx Margin setting for low power 
>>>> consumption.
>>>> +
>>>> +      qcom,no-dfe-support:
>>>> +        type: boolean
>>>> +        description: Disable DFE (Decision Feedback Equalizer), 
>>>> which mitigates
>>>> +          intersymbol interference and some reflections caused by 
>>>> impedance mismatches.
>>>> +
>>>> +      qcom,nfts:
>>>> +        $ref: /schemas/types.yaml#/definitions/uint32
>>>> +        description:
>>>> +          Number of Fast Training Sequence (FTS) used during L0s to 
>>>> L0 exit
>>>> +          for bit and Symbol lock.
>>>
>>> Also something common.
>>>
>>> The problem I have with all these properties is you are using them on
>>> both the upstream and downstream sides of the PCIe links. They belong in
>>> either the device's node (downstream) or the bus's node (upstream).
>>>
>> This switch allows us to configure both upstream, downstream ports and
>> also embedded Ethernet port which is internal to the switch. These
>> properties are applicable for all of those.
>>>> +
>>>> +    allOf:
>>>> +      - $ref: /schemas/pci/pci-bus.yaml#
>>>
>>> pci-pci-bridge.yaml is more specific and closer to what this device is.
>>>
>> I tried this now, I was getting warning saying the compatible
>> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: pcie@0,0: compatible: ['pci1179,0623'] does not contain items matching the given schema
>>          from schema $id: 
>> http://devicetree.org/schemas/pci/qcom,qps615.yaml#
>> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb: pcie@0,0: Unevaluated properties are not allowed ('#address-cells', '#size-cells', 'bus-range', 'device_type', 'ranges' were unexpected)
>>
>> I think pci-pci-bridge is expecting the compatible string in this format
>> only "pciclass,0604".
>>
>>>> +
>>>> +unevaluatedProperties: false
>>>> +
>>>> +required:
>>>> +  - vdd18-supply
>>>> +  - vdd09-supply
>>>> +  - vddc-supply
>>>> +  - vddio1-supply
>>>> +  - vddio2-supply
>>>> +  - vddio18-supply
>>>> +  - i2c-parent
>>>> +  - reset-gpios
>>>> +
>>>> +examples:
>>>> +  - |
>>>> +
>>>> +    #include <dt-bindings/gpio/gpio.h>
>>>> +
>>>> +    pcie {
>>>> +        #address-cells = <3>;
>>>> +        #size-cells = <2>;
>>>> +
>>>> +        pcie@0 {
>>>> +            device_type = "pci";
>>>> +            reg = <0x0 0x0 0x0 0x0 0x0>;
>>>> +
>>>> +            #address-cells = <3>;
>>>> +            #size-cells = <2>;
>>>> +            ranges;
>>>> +            bus-range = <0x01 0xff>;
>>>> +
>>>> +            pcie@0,0 {
>>>> +                compatible = "pci1179,0623";
>>>> +                reg = <0x10000 0x0 0x0 0x0 0x0>;
>>>> +                device_type = "pci";
>>>> +                #address-cells = <3>;
>>>> +                #size-cells = <2>;
>>>> +                ranges;
>>>> +                bus-range = <0x02 0xff>;
>>>> +
>>>> +                i2c-parent = <&qup_i2c 0x77>;
>>>> +
>>>> +                vdd18-supply = <&vdd>;
>>>> +                vdd09-supply = <&vdd>;
>>>> +                vddc-supply = <&vdd>;
>>>> +                vddio1-supply = <&vdd>;
>>>> +                vddio2-supply = <&vdd>;
>>>> +                vddio18-supply = <&vdd>;
>>>> +
>>>> +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
>>>> +
>>>> +                pcie@1,0 {
>>>> +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
>>>> +                    #address-cells = <3>;
>>>> +                    #size-cells = <2>;
>>>> +                    device_type = "pci";
>>>> +                    ranges;
>>>> +                    bus-range = <0x03 0xff>;
>>>> +
>>>> +                    qcom,no-dfe-support;
>>>> +                };
>>>> +
>>>> +                pcie@2,0 {
>>>> +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
>>>> +                    #address-cells = <3>;
>>>> +                    #size-cells = <2>;
>>>> +                    device_type = "pci";
>>>> +                    ranges;
>>>> +                    bus-range = <0x04 0xff>;
>>>> +
>>>> +                    qcom,nfts = <10>;
>>>> +                };
>>>> +
>>>> +                pcie@3,0 {
>>>> +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
>>>> +                    #address-cells = <3>;
>>>> +                    #size-cells = <2>;
>>>> +                    device_type = "pci";
>>>> +                    ranges;
>>>> +                    bus-range = <0x05 0xff>;
>>>> +
>>>> +                    qcom,tx-amplitude-millivolt = <10>;
>>>> +                    pcie@0,0 {
>>>> +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
>>>> +                        #address-cells = <3>;
>>>> +                        #size-cells = <2>;
>>>> +                        device_type = "pci";
>>>
>>> There's a 2nd PCI-PCI bridge?
>> This the embedded ethernet port which is as part of DSP3.
>>
> Hi Rob,
> 
> Can you please check my response on your queries, if you need
> any extra information, we can provide to sort this out.
> 
> - Krishna Chaitanya.
>> - Krishna Chaitanya

A gentle ping as its been more than 2 weeks.

- Krishna Chaitanya.
.
>>>
>>>> +                        ranges;
>>>> +
>>>> +                        qcom,l1-entry-delay-ns = <10>;
>>>> +                    };
>>>> +
>>>> +                    pcie@0,1 {
>>>> +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
>>>> +                        #address-cells = <3>;
>>>> +                        #size-cells = <2>;
>>>> +                        device_type = "pci";
>>>> +                        ranges;
>>>> +
>>>> +                        qcom,l0s-entry-delay-ns = <10>;
>>>> +                    };
>>>> +                };
>>>> +            };
>>>> +        };
>>>> +    };
>>>>
>>>> -- 
>>>> 2.34.1
>>>>
>>
>
Krishna Chaitanya Chundru Dec. 23, 2024, 4:48 p.m. UTC | #16
On 12/11/2024 11:30 AM, Manivannan Sadhasivam wrote:
> On Wed, Dec 04, 2024 at 03:25:59PM -0600, Bjorn Helgaas wrote:
>> On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
>>> Add binding describing the Qualcomm PCIe switch, QPS615,
>>> which provides Ethernet MAC integrated to the 3rd downstream port
>>> and two downstream PCIe ports.
>>
>>> +$defs:
>>> +  qps615-node:
>>> +    type: object
>>> +
>>> +    properties:
>>> +      qcom,l0s-entry-delay-ns:
>>> +        description: Aspm l0s entry delay.
>>> +
>>> +      qcom,l1-entry-delay-ns:
>>> +        description: Aspm l1 entry delay.
>>
>> To match spec usage:
>> s/Aspm/ASPM/
>> s/l0s/L0s/
>> s/l1/L1/
>>
>> Other than the fact that qps615 needs the driver to configure these,
>> there's nothing qcom-specific here, so I suggest the names should omit
>> "qcom" and include "aspm".
>>
> 
> In that case, these properties should be documented in dt-schema:
> https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/pci/pci-bus-common.yaml
> 
> - Mani
I am fine to move to pci-bus-common.yaml but currently these are being 
used by qps615 only I hope that is fine.

- Krishna Chaitanya.
>
Dmitry Baryshkov Dec. 23, 2024, 6:57 p.m. UTC | #17
On Sun, Nov 24, 2024 at 07:02:48AM +0530, Krishna Chaitanya Chundru wrote:
> 
> 
> On 11/15/2024 9:48 PM, Rob Herring wrote:
> > On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> > > Add binding describing the Qualcomm PCIe switch, QPS615,
> > > which provides Ethernet MAC integrated to the 3rd downstream port
> > > and two downstream PCIe ports.
> > > 
> > > Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> > > ---
> > >   .../devicetree/bindings/pci/qcom,qps615.yaml       | 205 +++++++++++++++++++++
> > >   1 file changed, 205 insertions(+)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> > > new file mode 100644
> > > index 000000000000..e6a63a0bb0f3
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> > > @@ -0,0 +1,205 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Qualcomm QPS615 PCIe switch
> > > +
> > > +maintainers:
> > > +  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
> > > +
> > > +description: |
> > > +  Qualcomm QPS615 PCIe switch has one upstream and three downstream
> > > +  ports. The 3rd downstream port has integrated endpoint device of
> > > +  Ethernet MAC. Other two downstream ports are supposed to connect
> > > +  to external device.
> > > +
> > > +  The QPS615 PCIe switch can be configured through I2C interface before
> > > +  PCIe link is established to change FTS, ASPM related entry delays,
> > > +  tx amplitude etc for better power efficiency and functionality.
> > > +
> > > +properties:
> > > +  compatible:
> > > +    enum:
> > > +      - pci1179,0623
> > > +
> > > +  reg:
> > > +    maxItems: 1
> > > +
> > > +  i2c-parent:
> > > +    $ref: /schemas/types.yaml#/definitions/phandle-array
> > > +    description: |
> > 
> > Don't need '|' if no formatting to preserve.
> > 
> ack
> > > +      A phandle to the parent I2C node and the slave address of the device
> > > +      used to do configure qps615 to change FTS, tx amplitude etc.
> > > +    items:
> > > +      - description: Phandle to the I2C controller node
> > > +      - description: I2C slave address
> > > +
> > > +  vdd18-supply: true
> > > +
> > > +  vdd09-supply: true
> > > +
> > > +  vddc-supply: true
> > > +
> > > +  vddio1-supply: true
> > > +
> > > +  vddio2-supply: true
> > > +
> > > +  vddio18-supply: true
> > > +
> > > +  reset-gpios:
> > > +    maxItems: 1
> > > +    description:
> > > +      GPIO controlling the RESX# pin.
> > 
> > Is the PERST# or something else?
> > 
> it is not PERST GPIO, it is similar to PERST in terms
> of functionality which brings switch out from reset.

Do you have an actual PERST# on upstream facing port? Is it a separate
wire? Judging by the RB3 Gen2 this line is being used as PERST#

> > > +
> > > +  qps615,axi-clk-freq-hz:
> > 
> > qps615 is not a vendor prefix.
> > 
> > > +    description:
> > > +      AXI clock rate which is internal bus of the switch
> > > +      The switch only runs in two frequencies i.e 250MHz and 125MHz.
> > > +    enum: [125000000, 250000000]
> > > +
> > > +allOf:
> > > +  - $ref: "#/$defs/qps615-node"
> > > +
> > > +patternProperties:
> > > +  "@1?[0-9a-f](,[0-7])?$":
> > 
> > You have 3 ports. So isn't this fixed and limited to 0-2?
> > 
> sure I will change it to below as suggested
> "@1?[0-3](,[0-1])?$"

Why do you still need '1?' ?

> > > +    description: child nodes describing the internal downstream ports
> > > +      the qps615 switch.
> > 
> > Please be consistent with starting after the ':' or on the next line.
> > 
> > And start with capital C.
> > 
> > 
> ack
> 
> > > +    type: object
> > > +    $ref: "#/$defs/qps615-node"
> > > +    unevaluatedProperties: false
> > > +
> > > +$defs:
> > > +  qps615-node:
> > > +    type: object
> > > +
> > > +    properties:
> > > +      qcom,l0s-entry-delay-ns:
> > > +        description: Aspm l0s entry delay.
> > > +
> > > +      qcom,l1-entry-delay-ns:
> > > +        description: Aspm l1 entry delay.
> > 
> > These should probably be common being standard PCIe things. Though, why
> > are they needed? I'm sure the timing is defined by the PCIe spec, so
> > they are not compliant?
> > 
> Usually the firmware in the endpoints/switches should do this these
> configurations. But the qps615 PCIe switch doesn't have any firmware
> running to configure these. So the hardware exposes i2c interface to
> configure these before link training.

If they are following the standard, why do you need to have them in the
DT? Can you hardcode thos evalues in the driver?

> > > +
> > > +      qcom,tx-amplitude-millivolt:
> > > +        $ref: /schemas/types.yaml#/definitions/uint32
> > > +        description: Change Tx Margin setting for low power consumption.
> > > +
> > > +      qcom,no-dfe-support:
> > > +        type: boolean
> > > +        description: Disable DFE (Decision Feedback Equalizer), which mitigates
> > > +          intersymbol interference and some reflections caused by impedance mismatches.
> > > +
> > > +      qcom,nfts:
> > > +        $ref: /schemas/types.yaml#/definitions/uint32
> > > +        description:
> > > +          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
> > > +          for bit and Symbol lock.
> > 
> > Also something common.
> > 
> > The problem I have with all these properties is you are using them on
> > both the upstream and downstream sides of the PCIe links. They belong in
> > either the device's node (downstream) or the bus's node (upstream).
> > 
> This switch allows us to configure both upstream, downstream ports and
> also embedded Ethernet port which is internal to the switch. These
> properties are applicable for all of those.
> > > +
> > > +    allOf:
> > > +      - $ref: /schemas/pci/pci-bus.yaml#
> > 
> > pci-pci-bridge.yaml is more specific and closer to what this device is.
> > 
> I tried this now, I was getting warning saying the compatible
> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb:
> pcie@0,0: compatible: ['pci1179,0623'] does not contain items matching the
> given schema
>         from schema $id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb:
> pcie@0,0: Unevaluated properties are not allowed ('#address-cells',
> '#size-cells', 'bus-range', 'device_type', 'ranges' were unexpected)
> 
> I think pci-pci-bridge is expecting the compatible string in this format
> only "pciclass,0604".

I think the pci-pci-bridge schema requires to have "pciclass,0604" among
other compatibles. So you should be able to do something like:

compatible = "pci1179,0623", "pciclass,0604";

At least if follows PCI Bus Binding to Open Firmware document.

> 
> > > +
> > > +unevaluatedProperties: false
> > > +
> > > +required:
> > > +  - vdd18-supply
> > > +  - vdd09-supply
> > > +  - vddc-supply
> > > +  - vddio1-supply
> > > +  - vddio2-supply
> > > +  - vddio18-supply
> > > +  - i2c-parent
> > > +  - reset-gpios
> > > +
> > > +examples:
> > > +  - |
> > > +
> > > +    #include <dt-bindings/gpio/gpio.h>
> > > +
> > > +    pcie {
> > > +        #address-cells = <3>;
> > > +        #size-cells = <2>;
> > > +
> > > +        pcie@0 {
> > > +            device_type = "pci";
> > > +            reg = <0x0 0x0 0x0 0x0 0x0>;
> > > +
> > > +            #address-cells = <3>;
> > > +            #size-cells = <2>;
> > > +            ranges;
> > > +            bus-range = <0x01 0xff>;
> > > +
> > > +            pcie@0,0 {
> > > +                compatible = "pci1179,0623";
> > > +                reg = <0x10000 0x0 0x0 0x0 0x0>;
> > > +                device_type = "pci";
> > > +                #address-cells = <3>;
> > > +                #size-cells = <2>;
> > > +                ranges;
> > > +                bus-range = <0x02 0xff>;
> > > +
> > > +                i2c-parent = <&qup_i2c 0x77>;
> > > +
> > > +                vdd18-supply = <&vdd>;
> > > +                vdd09-supply = <&vdd>;
> > > +                vddc-supply = <&vdd>;
> > > +                vddio1-supply = <&vdd>;
> > > +                vddio2-supply = <&vdd>;
> > > +                vddio18-supply = <&vdd>;
> > > +
> > > +                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
> > > +
> > > +                pcie@1,0 {
> > > +                    reg = <0x20800 0x0 0x0 0x0 0x0>;
> > > +                    #address-cells = <3>;
> > > +                    #size-cells = <2>;
> > > +                    device_type = "pci";
> > > +                    ranges;
> > > +                    bus-range = <0x03 0xff>;
> > > +
> > > +                    qcom,no-dfe-support;
> > > +                };
> > > +
> > > +                pcie@2,0 {
> > > +                    reg = <0x21000 0x0 0x0 0x0 0x0>;
> > > +                    #address-cells = <3>;
> > > +                    #size-cells = <2>;
> > > +                    device_type = "pci";
> > > +                    ranges;
> > > +                    bus-range = <0x04 0xff>;
> > > +
> > > +                    qcom,nfts = <10>;
> > > +                };
> > > +
> > > +                pcie@3,0 {
> > > +                    reg = <0x21800 0x0 0x0 0x0 0x0>;
> > > +                    #address-cells = <3>;
> > > +                    #size-cells = <2>;
> > > +                    device_type = "pci";
> > > +                    ranges;
> > > +                    bus-range = <0x05 0xff>;
> > > +
> > > +                    qcom,tx-amplitude-millivolt = <10>;
> > > +                    pcie@0,0 {
> > > +                        reg = <0x50000 0x0 0x0 0x0 0x0>;
> > > +                        #address-cells = <3>;
> > > +                        #size-cells = <2>;
> > > +                        device_type = "pci";
> > 
> > There's a 2nd PCI-PCI bridge?
> This the embedded ethernet port which is as part of DSP3.

So is there an adidtional bus for that ethernet device?

> 
> - Krishna Chaitanya.
> > 
> > > +                        ranges;
> > > +
> > > +                        qcom,l1-entry-delay-ns = <10>;
> > > +                    };
> > > +
> > > +                    pcie@0,1 {
> > > +                        reg = <0x50100 0x0 0x0 0x0 0x0>;
> > > +                        #address-cells = <3>;
> > > +                        #size-cells = <2>;
> > > +                        device_type = "pci";
> > > +                        ranges;
> > > +
> > > +                        qcom,l0s-entry-delay-ns = <10>;
> > > +                    };

What is this?

> > > +                };
> > > +            };
> > > +        };
> > > +    };
> > > 
> > > -- 
> > > 2.34.1
> > >
Dmitry Baryshkov Dec. 23, 2024, 6:58 p.m. UTC | #18
On Mon, Dec 23, 2024 at 10:18:24PM +0530, Krishna Chaitanya Chundru wrote:
> 
> 
> On 12/11/2024 11:30 AM, Manivannan Sadhasivam wrote:
> > On Wed, Dec 04, 2024 at 03:25:59PM -0600, Bjorn Helgaas wrote:
> > > On Tue, Nov 12, 2024 at 08:31:33PM +0530, Krishna chaitanya chundru wrote:
> > > > Add binding describing the Qualcomm PCIe switch, QPS615,
> > > > which provides Ethernet MAC integrated to the 3rd downstream port
> > > > and two downstream PCIe ports.
> > > 
> > > > +$defs:
> > > > +  qps615-node:
> > > > +    type: object
> > > > +
> > > > +    properties:
> > > > +      qcom,l0s-entry-delay-ns:
> > > > +        description: Aspm l0s entry delay.
> > > > +
> > > > +      qcom,l1-entry-delay-ns:
> > > > +        description: Aspm l1 entry delay.
> > > 
> > > To match spec usage:
> > > s/Aspm/ASPM/
> > > s/l0s/L0s/
> > > s/l1/L1/
> > > 
> > > Other than the fact that qps615 needs the driver to configure these,
> > > there's nothing qcom-specific here, so I suggest the names should omit
> > > "qcom" and include "aspm".
> > > 
> > 
> > In that case, these properties should be documented in dt-schema:
> > https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/pci/pci-bus-common.yaml
> > 
> > - Mani
> I am fine to move to pci-bus-common.yaml but currently these are being used
> by qps615 only I hope that is fine.

With bindings there is no such thing as "currently". Once defined they
become an ABI and must not be changed.
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
new file mode 100644
index 000000000000..e6a63a0bb0f3
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
@@ -0,0 +1,205 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm QPS615 PCIe switch
+
+maintainers:
+  - Krishna chaitanya chundru <quic_krichai@quicinc.com>
+
+description: |
+  Qualcomm QPS615 PCIe switch has one upstream and three downstream
+  ports. The 3rd downstream port has integrated endpoint device of
+  Ethernet MAC. Other two downstream ports are supposed to connect
+  to external device.
+
+  The QPS615 PCIe switch can be configured through I2C interface before
+  PCIe link is established to change FTS, ASPM related entry delays,
+  tx amplitude etc for better power efficiency and functionality.
+
+properties:
+  compatible:
+    enum:
+      - pci1179,0623
+
+  reg:
+    maxItems: 1
+
+  i2c-parent:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description: |
+      A phandle to the parent I2C node and the slave address of the device
+      used to do configure qps615 to change FTS, tx amplitude etc.
+    items:
+      - description: Phandle to the I2C controller node
+      - description: I2C slave address
+
+  vdd18-supply: true
+
+  vdd09-supply: true
+
+  vddc-supply: true
+
+  vddio1-supply: true
+
+  vddio2-supply: true
+
+  vddio18-supply: true
+
+  reset-gpios:
+    maxItems: 1
+    description:
+      GPIO controlling the RESX# pin.
+
+  qps615,axi-clk-freq-hz:
+    description:
+      AXI clock rate which is internal bus of the switch
+      The switch only runs in two frequencies i.e 250MHz and 125MHz.
+    enum: [125000000, 250000000]
+
+allOf:
+  - $ref: "#/$defs/qps615-node"
+
+patternProperties:
+  "@1?[0-9a-f](,[0-7])?$":
+    description: child nodes describing the internal downstream ports
+      the qps615 switch.
+    type: object
+    $ref: "#/$defs/qps615-node"
+    unevaluatedProperties: false
+
+$defs:
+  qps615-node:
+    type: object
+
+    properties:
+      qcom,l0s-entry-delay-ns:
+        description: Aspm l0s entry delay.
+
+      qcom,l1-entry-delay-ns:
+        description: Aspm l1 entry delay.
+
+      qcom,tx-amplitude-millivolt:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description: Change Tx Margin setting for low power consumption.
+
+      qcom,no-dfe-support:
+        type: boolean
+        description: Disable DFE (Decision Feedback Equalizer), which mitigates
+          intersymbol interference and some reflections caused by impedance mismatches.
+
+      qcom,nfts:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description:
+          Number of Fast Training Sequence (FTS) used during L0s to L0 exit
+          for bit and Symbol lock.
+
+    allOf:
+      - $ref: /schemas/pci/pci-bus.yaml#
+
+unevaluatedProperties: false
+
+required:
+  - vdd18-supply
+  - vdd09-supply
+  - vddc-supply
+  - vddio1-supply
+  - vddio2-supply
+  - vddio18-supply
+  - i2c-parent
+  - reset-gpios
+
+examples:
+  - |
+
+    #include <dt-bindings/gpio/gpio.h>
+
+    pcie {
+        #address-cells = <3>;
+        #size-cells = <2>;
+
+        pcie@0 {
+            device_type = "pci";
+            reg = <0x0 0x0 0x0 0x0 0x0>;
+
+            #address-cells = <3>;
+            #size-cells = <2>;
+            ranges;
+            bus-range = <0x01 0xff>;
+
+            pcie@0,0 {
+                compatible = "pci1179,0623";
+                reg = <0x10000 0x0 0x0 0x0 0x0>;
+                device_type = "pci";
+                #address-cells = <3>;
+                #size-cells = <2>;
+                ranges;
+                bus-range = <0x02 0xff>;
+
+                i2c-parent = <&qup_i2c 0x77>;
+
+                vdd18-supply = <&vdd>;
+                vdd09-supply = <&vdd>;
+                vddc-supply = <&vdd>;
+                vddio1-supply = <&vdd>;
+                vddio2-supply = <&vdd>;
+                vddio18-supply = <&vdd>;
+
+                reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
+
+                pcie@1,0 {
+                    reg = <0x20800 0x0 0x0 0x0 0x0>;
+                    #address-cells = <3>;
+                    #size-cells = <2>;
+                    device_type = "pci";
+                    ranges;
+                    bus-range = <0x03 0xff>;
+
+                    qcom,no-dfe-support;
+                };
+
+                pcie@2,0 {
+                    reg = <0x21000 0x0 0x0 0x0 0x0>;
+                    #address-cells = <3>;
+                    #size-cells = <2>;
+                    device_type = "pci";
+                    ranges;
+                    bus-range = <0x04 0xff>;
+
+                    qcom,nfts = <10>;
+                };
+
+                pcie@3,0 {
+                    reg = <0x21800 0x0 0x0 0x0 0x0>;
+                    #address-cells = <3>;
+                    #size-cells = <2>;
+                    device_type = "pci";
+                    ranges;
+                    bus-range = <0x05 0xff>;
+
+                    qcom,tx-amplitude-millivolt = <10>;
+                    pcie@0,0 {
+                        reg = <0x50000 0x0 0x0 0x0 0x0>;
+                        #address-cells = <3>;
+                        #size-cells = <2>;
+                        device_type = "pci";
+                        ranges;
+
+                        qcom,l1-entry-delay-ns = <10>;
+                    };
+
+                    pcie@0,1 {
+                        reg = <0x50100 0x0 0x0 0x0 0x0>;
+                        #address-cells = <3>;
+                        #size-cells = <2>;
+                        device_type = "pci";
+                        ranges;
+
+                        qcom,l0s-entry-delay-ns = <10>;
+                    };
+                };
+            };
+        };
+    };