Re: [PATCH v2 5/5] dt-bindings: net: ipq4019-mdio: Document ipq5332 platform

[Jie Luo]

On 12/13/2023 12:06 AM, Conor Dooley wrote:
> On Tue, Dec 12, 2023 at 07:51:50PM +0800, Luo Jie wrote:
> > Update the yaml file for the new DTS properties.
> >
> > 1. cmn-reference-clock for the CMN PLL source clock select.
> > 2. clock-frequency for MDIO clock frequency config.
> > 3. add uniphy AHB & SYS GCC clocks.
> > 4. add reset-gpios for MDIO bus level reset.
> >
> > Signed-off-by: Luo Jie <quic_luoj@xxxxxxxxxxx>
> > ---
> >   .../bindings/net/qcom,ipq4019-mdio.yaml       | 157 +++++++++++++++++-
> >   1 file changed, 153 insertions(+), 4 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/net/qcom,ipq4019-mdio.yaml b/Documentation/devicetree/bindings/net/qcom,ipq4019-mdio.yaml
> > index 3407e909e8a7..9546a6ad7841 100644
> > --- a/Documentation/devicetree/bindings/net/qcom,ipq4019-mdio.yaml
> > +++ b/Documentation/devicetree/bindings/net/qcom,ipq4019-mdio.yaml
> > @@ -20,6 +20,8 @@ properties:
> >             - enum:
> >                 - qcom,ipq6018-mdio
> >                 - qcom,ipq8074-mdio
> > +              - qcom,ipq9574-mdio
> > +              - qcom,ipq5332-mdio
> >             - const: qcom,ipq4019-mdio
> >   
> >     "#address-cells":
> > @@ -30,19 +32,71 @@ properties:
> >   
> >     reg:
> >       minItems: 1
> > -    maxItems: 2
> > +    maxItems: 5
> >       description:
> > -      the first Address and length of the register set for the MDIO controller.
> > -      the second Address and length of the register for ethernet LDO, this second
> > -      address range is only required by the platform IPQ50xx.
> > +      the first Address and length of the register set for the MDIO controller,
> > +      the optional second, third and fourth address and length of the register
> > +      for ethernet LDO, these three address range are required by the platform
> > +      IPQ50xx/IPQ5332/IPQ9574, the last address and length is for the CMN clock
> > +      to select the reference clock.
> > +
> > +  reg-names:
> > +    minItems: 1
> > +    maxItems: 5
> >   
> >     clocks:
> > +    minItems: 1
> >       items:
> >         - description: MDIO clock source frequency fixed to 100MHZ
> > +      - description: UNIPHY0 AHB clock source frequency fixed to 100MHZ
> > +      - description: UNIPHY1 AHB clock source frequency fixed to 100MHZ
> > +      - description: UNIPHY0 SYS clock source frequency fixed to 24MHZ
> > +      - description: UNIPHY1 SYS clock source frequency fixed to 24MHZ
> >   
> >     clock-names:
> > +    minItems: 1
> >       items:
> >         - const: gcc_mdio_ahb_clk
> > +      - const: gcc_uniphy0_ahb_clk
> > +      - const: gcc_uniphy1_ahb_clk
> > +      - const: gcc_uniphy0_sys_clk
> > +      - const: gcc_uniphy1_sys_clk
>
> > +  cmn-reference-clock:
> > +    oneOf:
> > +      - items:
> > +          - enum:
> > +              - 0   # CMN PLL reference internal 48MHZ
> > +              - 1   # CMN PLL reference external 25MHZ
> > +              - 2   # CMN PLL reference external 31250KHZ
> > +              - 3   # CMN PLL reference external 40MHZ
> > +              - 4   # CMN PLL reference external 48MHZ
> > +              - 5   # CMN PLL reference external 50MHZ
> > +              - 6   # CMN PLL reference internal 96MHZ
>
> Why is this not represented by an element of the clocks property?

This property is for the reference clock source selection of CMN PLL,
CMN PLL generates the different clock rates for the different Ethernet
blocks, this CMN PLL configuration is not located in the GCC, so the
clock framework can't be used, which is the general hardware register
instead of RCG register for GCC.

> > +  clock-frequency:
> > +    oneOf:
> > +      - items:
> > +          - enum:
> > +              - 12500000
> > +              - 6250000
> > +              - 3125000
> > +              - 1562500
> > +              - 781250
> > +              - 390625
> > +    description:
> > +      The MDIO bus clock that must be output by the MDIO bus hardware,
> > +      only the listed frequecies above can be configured, other frequency
> > +      will cause malfunction. If absent, the default hardware value is used.
>
> Likewise.
>
> Your commit message contains a bullet point list of what you are doing,
> but there's no explanation here for why custom properties are required
> to provide clock information.
>
> Thanks,
> Conor.

Hi Conor,
This property clock-frequency is optional to configure the MDIO working
clock rate, and this is the MDIO general DT property, since the hardware
default clock rate is 390625HZ, there is requirement for higher clock 
rate in the normal working case, i will update this information in the
next patch set.