Re: [PATCH v5 2/5] dt-bindings: arm: msm: Convert kpss-acc driver Documentation to yaml

[Christian Marangi <ansuelsmth@xxxxxxxxx>]

On Fri, Sep 16, 2022 at 02:17:15PM -0500, Rob Herring wrote:
> On Wed, Sep 14, 2022 at 04:22:53PM +0200, Christian Marangi wrote:
> > Convert kpss-acc driver Documentation to yaml.
> > The original Documentation was wrong all along. Fix it while we are
> > converting it.
> > The example was wrong as kpss-acc-v2 should only expose the regs but we
> > don't have any driver that expose additional clocks. The kpss-acc driver
> > is only specific to v1. For this exact reason, limit all the additional
> > bindings (clocks, clock-names, clock-output-names and #clock-cells) to
> > v1 and also flag that these bindings should NOT be used for v2.
> 
> Odd that a clock controller has no clocks, but okay.
>

As said in the commit v2 is only used for regs. v2 it's only used in
arch/arm/mach-qcom/platsmp.c to setup stuff cpu hotplug and bringup.

Should we split the 2 driver? To me the acc naming seems to be just
recycled for v2 and it's not really a clk controller.

So keeping v2 in arm/msm/qcom,kpss-acc-v2.yaml and v1 moved to clock?

> > 
> > Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
> > ---
> >  .../bindings/arm/msm/qcom,kpss-acc.txt        | 49 ----------
> >  .../bindings/arm/msm/qcom,kpss-acc.yaml       | 93 +++++++++++++++++++
> 
> As this is a clock controller, please move to bindings/clock/
> 
> >  2 files changed, 93 insertions(+), 49 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
> >  create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.yaml
> 
> > diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.yaml b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.yaml
> > new file mode 100644
> > index 000000000000..5e16121d9f0d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.yaml
> > @@ -0,0 +1,93 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/msm/qcom,kpss-acc.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Krait Processor Sub-system (KPSS) Application Clock Controller (ACC)
> > +
> > +maintainers:
> > +  - Christian Marangi <ansuelsmth@xxxxxxxxx>
> > +
> > +description: |
> 
> Don't need '|' if no formatting to preserve.
> 
> > +  The KPSS ACC provides clock, power domain, and reset control to a Krait CPU.
> > +  There is one ACC register region per CPU within the KPSS remapped region as
> > +  well as an alias register region that remaps accesses to the ACC associated
> > +  with the CPU accessing the region.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - qcom,kpss-acc-v1
> > +      - qcom,kpss-acc-v2
> > +
> > +  reg:
> > +    items:
> > +      - description: Base address and size of the register region
> > +      - description: Optional base address and size of the alias register region
> > +
> > +  clocks:
> > +    items:
> > +      - description: phandle to pll8_vote
> 
> Always a phandle (and arg), so that's redundant. Really, if there's not 
> more to add that what clock-names says, then just 'maxItems: 2' is fine.
> 
> > +      - description: phandle to pxo_board
> > +
> > +  clock-names:
> > +    items:
> > +      - const: pll8_vote
> > +      - const: pxo
> > +
> > +  clock-output-names:
> > +    description: Name of the aux clock. Krait can have at most 4 cpu.
> > +    enum:
> > +      - acpu0_aux
> > +      - acpu1_aux
> > +      - acpu2_aux
> > +      - acpu3_aux
> > +
> > +  '#clock-cells':
> > +    const: 0
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +
> > +if:
> > +  properties:
> > +    compatible:
> > +      contains:
> > +        const: qcom,kpss-acc-v1
> > +then:
> > +  required:
> > +    - clocks
> > +    - clock-names
> > +    - clock-output-names
> > +    - '#clock-cells'
> > +else:
> > +  properties:
> > +    clocks: false
> > +    clock-names: false
> > +    clock-output-names: false
> > +    '#clock-cells': false
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/clock/qcom,gcc-ipq806x.h>
> > +
> > +    clock-controller@2088000 {
> > +      compatible = "qcom,kpss-acc-v1";
> > +      reg = <0x02088000 0x1000>, <0x02008000 0x1000>;
> > +      clocks = <&gcc PLL8_VOTE>, <&pxo_board>;
> > +      clock-names = "pll8_vote", "pxo";
> > +      clock-output-names = "acpu0_aux";
> > +      #clock-cells = <0>;
> > +    };
> > +
> > +  - |
> > +    clock-controller@f9088000 {
> > +      compatible = "qcom,kpss-acc-v2";
> > +      reg = <0xf9088000 0x1000>,
> > +            <0xf9008000 0x1000>;
> > +    };
> > +...
> > -- 
> > 2.37.2
> > 
> > 

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