From c8ff5351b598cd722c9cf8a84259887bd1af2e0e Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Tue, 4 Jun 2019 16:14:27 +0800 Subject: [PATCH] dt-bindings: mmc: sprd: Add PHY DLL delay documentation Introduce some PHY DLL delays properties to help to sample the PHY clock. Signed-off-by: Baolin Wang Signed-off-by: Ulf Hansson --- .../devicetree/bindings/mmc/sdhci-sprd.txt | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/sdhci-sprd.txt b/Documentation/devicetree/bindings/mmc/sdhci-sprd.txt index a285c773acd0..e675397fa428 100644 --- a/Documentation/devicetree/bindings/mmc/sdhci-sprd.txt +++ b/Documentation/devicetree/bindings/mmc/sdhci-sprd.txt @@ -20,6 +20,23 @@ Optional properties: - assigned-clocks: the same with "sdio" clock - assigned-clock-parents: the default parent of "sdio" clock +PHY DLL delays are used to delay the data valid window, and align the window +to sampling clock. PHY DLL delays can be configured by following properties, +and each property contains 4 cells which are used to configure the clock data +write line delay value, clock read command line delay value, clock read data +positive edge delay value and clock read data negative edge delay value. +Each cell's delay value unit is cycle of the PHY clock. + +- sprd,phy-delay-legacy: Delay value for legacy timing. +- sprd,phy-delay-sd-highspeed: Delay value for SD high-speed timing. +- sprd,phy-delay-sd-uhs-sdr50: Delay value for SD UHS SDR50 timing. +- sprd,phy-delay-sd-uhs-sdr104: Delay value for SD UHS SDR50 timing. +- sprd,phy-delay-mmc-highspeed: Delay value for MMC high-speed timing. +- sprd,phy-delay-mmc-ddr52: Delay value for MMC DDR52 timing. +- sprd,phy-delay-mmc-hs200: Delay value for MMC HS200 timing. +- sprd,phy-delay-mmc-hs400: Delay value for MMC HS400 timing. +- sprd,phy-delay-mmc-hs400es: Delay value for MMC HS400 enhanced strobe timing. + Examples: sdio0: sdio@20600000 { @@ -33,6 +50,7 @@ sdio0: sdio@20600000 { assigned-clocks = <&ap_clk CLK_EMMC_2X>; assigned-clock-parents = <&rpll CLK_RPLL_390M>; + sprd,phy-delay-sd-uhs-sdr104 = <0x3f 0x7f 0x2e 0x2e>; bus-width = <8>; non-removable; no-sdio; -- 2.25.1