[PATCH v4 2/2] dt: power: st: Provide bindings for ST's OPPs

Rob Herring robherring2 at gmail.com
Tue Jul 28 06:55:33 PDT 2015


On Mon, Jul 27, 2015 at 10:20 AM, Lee Jones <lee.jones at linaro.org> wrote:
> These OPPs are used in ST's CPUFreq implementation.
>
> Signed-off-by: Lee Jones <lee.jones at linaro.org>
> ---
>
> Changelog:
>  - None, new patch
>
>  Documentation/devicetree/bindings/power/opp-st.txt | 76 ++++++++++++++++++++++
>  1 file changed, 76 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/power/opp-st.txt
>
> diff --git a/Documentation/devicetree/bindings/power/opp-st.txt b/Documentation/devicetree/bindings/power/opp-st.txt
> new file mode 100644
> index 0000000..6eb2a91
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/opp-st.txt
> @@ -0,0 +1,76 @@
> +STMicroelectronics OPP (Operating Performance Points) Bindings
> +--------------------------------------------------------------
> +
> +Frequency Scaling only
> +----------------------
> +
> +Located in CPU's node:
> +
> +- operating-points     : [See: ./opp.txt]
> +
> +Example [safe]
> +--------------
> +
> +cpus {
> +       cpu at 0 {
> +                                /* kHz     uV   */
> +               operating-points = <1500000 0
> +                                   1200000 0
> +                                   800000  0
> +                                   500000  0>;
> +       };
> +};
> +
> +Dynamic Voltage and Frequency Scaling (DVFS)
> +--------------------------------------------
> +
> +Located in 'cpu0-opp-list' node [to be provided ONLY by the bootloader]:
> +
> +- compatible           : Should be "operating-points-v2-sti"
> +- opp{1..N}            : Each 'oppX' subnode will contain the following properties:
> + - opp-hz              : CPU frequency [Hz] for this OPP [See: ./opp.txt]
> + - st,avs              : List of available voltages [uV] indexed by process code

Add a unit suffix (-microvolt).

> + - st,cuts             : Cut version this OPP is suitable for [0xFF means ALL]
> + - st,substrate                : Substrate version this OPP is suitable for [0xFF means ALL]

How about not present means all?

> +- st,syscfg            : Phandle to Major number register
> +                               First cell: offset to major number
> +- st,syscfg-eng                : Phandle to Minor number and Pcode registers
> +                               First cell: offset to process code
> +                               Second cell: offset to minor number

Would the proposed nvmem binding work for this?

Rob



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