Document HS400 DQS trim value device tree property.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
trimmer value for non-tunable modes.
- nvidia,default-trim : Specify the default outbound clock trimmer
value.
+- nvidia,dqs-trim : Specify DQS trim value for HS400 timing
Notes on the pad calibration pull up and pulldown offset values:
- The property values are drive codes which are programmed into the
- The values are programmed to the Vendor Clock Control Register.
Please refer to the reference manual of the SoC for correct
values.
+ - The DQS trim values are only used on controllers which support
+ HS400 timing. Only SDMMC4 on Tegra210 and Tegra 186 supports
+ HS400.
Example:
sdhci@700b0000 {