Re: [v2 PATCH 2/3] Documentation: bindings: add description of PHY delays for sdhci-cadence

From: Rob Herring
Date: Wed Mar 15 2017 - 12:55:50 EST


On Mon, Mar 06, 2017 at 01:39:36PM +0000, Piotr Sroka wrote:
> Add description of new DLL PHY delays.

For the subject: "dt-bindings: mmc: ..."

>
> Signed-off-by: Piotr Sroka <piotrs@xxxxxxxxxxx>
> ---
> Changes for v2:
> - file was created in v2. It was a part of driver source file patch.
> - most delays were moved from dts file
> to data associated with an SoC specific compatible
> - description of delays was updated to be more clearly
> ---
> .../devicetree/bindings/mmc/sdhci-cadence.txt | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
> index c0f37cb..77c4b99 100644
> --- a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
> +++ b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
> @@ -19,6 +19,23 @@ if supported. See mmc.txt for details.
> - mmc-hs400-1_8v
> - mmc-hs400-1_2v
>
> +Some PHY delays can be configured by following properties.
> +Each delay property represents the fraction of the clock period.
> +The approximate delay value will be
> +(<delay property value>/128)*sdmclk_clock_period.
> +- phy-dll-delay-sdclk:
> + Value of the delay introduced on the sdclk output
> + for all modes except HS200, HS400 and HS400_ES.
> + Valid range = [0:0x7F].
> +- phy-dll-delay-sdclk-hsmmc:
> + Value of the delay introduced on the sdclk output
> + for HS200, HS400 and HS400_ES speed modes.
> + Valid range = [0:0x7F].
> +- phy-dll-delay-strobe:
> + Value of the delay introduced on the dat_strobe input
> + used in HS400 / HS400_ES speed modes.
> + Valid range = [0:0x7F].

These all vendor prefixes.

> +
> Example:
> emmc: sdhci@5a000000 {
> compatible = "socionext,uniphier-sd4hc", "cdns,sd4hc";
> @@ -29,4 +46,5 @@ Example:
> mmc-ddr-1_8v;
> mmc-hs200-1_8v;
> mmc-hs400-1_8v;
> + phy-dll-delay-sdclk = <0>;
> };
> --
> 2.2.2
>