SDHCI vendor tuning registers are configured using config setting framework. Document available config for Tegra SDHCI controllers. Signed-off-by: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx> --- .../bindings/mmc/nvidia,tegra20-sdhci.yaml | 36 +++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.yaml b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.yaml index 72987f0326a1..002bc1ffc156 100644 --- a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.yaml +++ b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.yaml @@ -177,6 +177,37 @@ properties: operates at a 1.8 V fixed I/O voltage. $ref: /schemas/types.yaml#/definitions/flag + config: + description: Config settings for SDHCI devices. + Config setting is the configuration based on chip/board/system + characterization on interface/controller settings. This is needed for + - making the controller internal configuration to better perform + - making the interface to work proper by setting drive strength, slew + rates etc + - making the low power leakage. + SDHCI has configuration based on device speed modes. + - common is set on all speeds and can be overridden by speed mode. + - List of speed modes and their config name + "default", /* MMC_TIMING_LEGACY */ + "sd-mmc-highspeed", /* MMC_TIMING_MMC_HS */ + "sd-mmc-highspeed", /* MMC_TIMING_SD_HS */ + "uhs-sdr12", /* MMC_TIMING_UHS_SDR12 */ + "uhs-sdr25", /* MMC_TIMING_UHS_SDR25 */ + "uhs-sdr50", /* MMC_TIMING_UHS_SDR50 */ + "uhs-sdr104", /* MMC_TIMING_UHS_SDR104 */ + "uhs-ddr52", /* MMC_TIMING_UHS_DDR50 */ + "uhs-ddr52", /* MMC_TIMING_MMC_DDR52 */ + "mmc-hs200", /* MMC_TIMING_MMC_HS200 */ + "mmc-hs400", /* MMC_TIMING_MMC_HS400 */ + type: object + unevaluatedProperties: true + properties: + nvidia,num-tuning-iter: + description: Specify DQS trim value for HS400 timing. + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 0 + maximum: 0xffff + required: - compatible - reg @@ -278,6 +309,11 @@ examples: wp-gpios = <&gpio 57 0>; /* gpio PH1 */ power-gpios = <&gpio 155 0>; /* gpio PT3 */ bus-width = <8>; + config { + mmc-hs200 { + nvidia,num-tuning-iter = <0x2>; + }; + }; }; - | -- 2.43.2