Re: [PATCH 04/14] dt-bindings: Add bindings for peci-aspeed

["Winiarska, Iwona" <iwona.winiarska@intel.com>]

On Thu, 2021-07-15 at 10:28 -0600, Rob Herring wrote:
> On Tue, Jul 13, 2021 at 12:04:37AM +0200, Iwona Winiarska wrote:
> > Add device tree bindings for the peci-aspeed controller driver.
> > 
> > Co-developed-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
> > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
> > Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
> > ---
> >  .../devicetree/bindings/peci/peci-aspeed.yaml | 111 ++++++++++++++++++
> >  1 file changed, 111 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/peci/peci-aspeed.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/peci/peci-aspeed.yaml b/Documentation/devicetree/bindings/peci/peci-aspeed.yaml
> > new file mode 100644
> > index 000000000000..6061e06009fb
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/peci/peci-aspeed.yaml
> > @@ -0,0 +1,111 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/peci/peci-aspeed.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Aspeed PECI Bus Device Tree Bindings
> > +
> > +maintainers:
> > +  - Iwona Winiarska <iwona.winiarska@intel.com>
> > +  - Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
> > +
> > +allOf:
> > +  - $ref: peci-controller.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - aspeed,ast2400-peci
> > +      - aspeed,ast2500-peci
> > +      - aspeed,ast2600-peci
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    description: |
> > +      Clock source for PECI controller. Should reference the external
> > +      oscillator clock.
> > +    maxItems: 1
> > +
> > +  resets:
> > +    maxItems: 1
> > +
> > +  clock-divider:
> > +    description: This value determines PECI controller internal clock
> > +      dividing rate. The divider will be calculated as 2 raised to the
> > +      power of the given value.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    minimum: 0
> > +    maximum: 7
> > +    default: 0
> > +
> 
> > +  msg-timing:
> > +    description: |
> > +      Message timing negotiation period. This value will determine the period
> > +      of message timing negotiation to be issued by PECI controller. The unit
> > +      of the programmed value is four times of PECI clock period.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    minimum: 0
> > +    maximum: 255
> > +    default: 1
> > +
> > +  addr-timing:
> > +    description: |
> > +      Address timing negotiation period. This value will determine the period
> > +      of address timing negotiation to be issued by PECI controller. The unit
> > +      of the programmed value is four times of PECI clock period.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    minimum: 0
> > +    maximum: 255
> > +    default: 1
> > +
> > +  rd-sampling-point:
> > +    description: |
> > +      Read sampling point selection. The whole period of a bit time will be
> > +      divided into 16 time frames. This value will determine the time frame
> > +      in which the controller will sample PECI signal for data read back.
> > +      Usually in the middle of a bit time is the best.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    minimum: 0
> > +    maximum: 15
> > +    default: 8
> > +
> > +  cmd-timeout-ms:
> > +    description: |
> > +      Command timeout in units of ms.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    minimum: 1
> > +    maximum: 1000
> > +    default: 1000
> 
> Are all of these properties common for PECI or specific to this 
> controller? The former needs to go into the common schema. The latter 
> need vendor prefixes.
> 

The latter, I'll add vendor prefixes in v2.

Thank you
-Iwona

> 
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +  - clocks
> > +  - resets
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +    #include <dt-bindings/clock/ast2600-clock.h>
> > +    peci-controller@1e78b000 {
> > +      compatible = "aspeed,ast2600-peci";
> > +      reg = <0x1e78b000 0x100>;
> > +      interrupts = <GIC_SPI 38 IRQ_TYPE_LEVEL_HIGH>;
> > +      clocks = <&syscon ASPEED_CLK_GATE_REF0CLK>;
> > +      resets = <&syscon ASPEED_RESET_PECI>;
> > +      clock-divider = <0>;
> > +      msg-timing = <1>;
> > +      addr-timing = <1>;
> > +      rd-sampling-point = <8>;
> > +      cmd-timeout-ms = <1000>;
> > +    };
> > +...
> > -- 
> > 2.31.1
> > 
> >