From b7783cfbd1589b877d3171ccb7bf2d526776ad7c Mon Sep 17 00:00:00 2001 From: Aapo Vienamo Date: Thu, 30 Aug 2018 18:06:05 +0300 Subject: [PATCH] dt-bindings: mmc: Add Tegra SDHCI sampling trimmer values Document the Tegra SDHCI inbound and outbound sampling trimmer values. Signed-off-by: Aapo Vienamo Reviewed-by: Rob Herring Acked-by: Thierry Reding Signed-off-by: Ulf Hansson --- .../devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt index 9713e05..edecf97 100644 --- a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt +++ b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt @@ -67,6 +67,10 @@ Optional properties for Tegra210 and Tegra186: - nvidia,pad-autocal-pull-up-offset-hs400, nvidia,pad-autocal-pull-down-offset-hs400 : Specify drive strength calibration offsets for HS400 mode. +- nvidia,default-tap : Specify the default inbound sampling clock + trimmer value for non-tunable modes. +- nvidia,default-trim : Specify the default outbound clock trimmer + value. Notes on the pad calibration pull up and pulldown offset values: - The property values are drive codes which are programmed into the @@ -77,6 +81,13 @@ Optional properties for Tegra210 and Tegra186: - The SDR104 and HS400 timing specific values are used in corresponding modes if specified. + Notes on tap and trim values: + - The values are used for compensating trace length differences + by adjusting the sampling point. + - The values are programmed to the Vendor Clock Control Register. + Please refer to the reference manual of the SoC for correct + values. + Example: sdhci@700b0000 { compatible = "nvidia,tegra210-sdhci", "nvidia,tegra124-sdhci"; -- 2.7.4