From 6f4b0919020a482e41af4e715efaa79f45f6cde6 Mon Sep 17 00:00:00 2001 From: Piotr Sroka Date: Tue, 21 Mar 2017 14:33:01 +0000 Subject: [PATCH] dt-bindings: mmc: add description of PHY delays for sdhci-cadence DTS properties are used instead of fixed data because PHY settings can be different for different chips/boards. Add description of new DLL PHY delays. Signed-off-by: Piotr Sroka Reviewed-by: Masahiro Yamada Acked-by: Rob Herring Signed-off-by: Ulf Hansson --- .../devicetree/bindings/mmc/sdhci-cadence.txt | 48 +++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt index c0f37cb41a9b..fa423c277853 100644 --- a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt +++ b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt @@ -19,6 +19,53 @@ if supported. See mmc.txt for details. - mmc-hs400-1_8v - mmc-hs400-1_2v +Some PHY delays can be configured by following properties. +PHY DLL input delays: +They are used to delay the data valid window, and align the window +to sampling clock. The delay starts from 5ns (for delay parameter equal to 0) +and it is increased by 2.5ns in each step. +- cdns,phy-input-delay-sd-highspeed: + Value of the delay in the input path for SD high-speed timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-legacy: + Value of the delay in the input path for legacy timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-sd-uhs-sdr12: + Value of the delay in the input path for SD UHS SDR12 timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-sd-uhs-sdr25: + Value of the delay in the input path for SD UHS SDR25 timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-sd-uhs-sdr50: + Value of the delay in the input path for SD UHS SDR50 timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-sd-uhs-ddr50: + Value of the delay in the input path for SD UHS DDR50 timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-mmc-highspeed: + Value of the delay in the input path for MMC high-speed timing + Valid range = [0:0x1F]. +- cdns,phy-input-delay-mmc-ddr: + Value of the delay in the input path for eMMC high-speed DDR timing + Valid range = [0:0x1F]. + +PHY DLL clock delays: +Each delay property represents the fraction of the clock period. +The approximate delay value will be +(/128)*sdmclk_clock_period. +- cdns,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]. +- cdns,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]. +- cdns,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]. + Example: emmc: sdhci@5a000000 { compatible = "socionext,uniphier-sd4hc", "cdns,sd4hc"; @@ -29,4 +76,5 @@ Example: mmc-ddr-1_8v; mmc-hs200-1_8v; mmc-hs400-1_8v; + cdns,phy-dll-delay-sdclk = <0>; }; -- 2.20.1