diff options
Diffstat (limited to 'Documentation/devicetree/bindings/mmc/marvell,xenon-sdhci.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/mmc/marvell,xenon-sdhci.txt | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mmc/marvell,xenon-sdhci.txt b/Documentation/devicetree/bindings/mmc/marvell,xenon-sdhci.txt new file mode 100644 index 000000000..ed1456f5c --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/marvell,xenon-sdhci.txt @@ -0,0 +1,172 @@ +Marvell Xenon SDHCI Controller device tree bindings +This file documents differences between the core mmc properties +described by mmc.txt and the properties used by the Xenon implementation. + +Multiple SDHCs might be put into a single Xenon IP, to save size and cost. +Each SDHC is independent and owns independent resources, such as register sets, +clock and PHY. +Each SDHC should have an independent device tree node. + +Required Properties: +- compatible: should be one of the following + - "marvell,armada-3700-sdhci": For controllers on Armada-3700 SoC. + Must provide a second register area and marvell,pad-type. + - "marvell,armada-ap806-sdhci": For controllers on Armada AP806. + - "marvell,armada-cp110-sdhci": For controllers on Armada CP110. + +- clocks: + Array of clocks required for SDHC. + Require at least input clock for Xenon IP core. For Armada AP806 and + CP110, the AXI clock is also mandatory. + +- clock-names: + Array of names corresponding to clocks property. + The input clock for Xenon IP core should be named as "core". + The input clock for the AXI bus must be named as "axi". + +- reg: + * For "marvell,armada-3700-sdhci", two register areas. + The first one for Xenon IP register. The second one for the Armada 3700 SoC + PHY PAD Voltage Control register. + Please follow the examples with compatible "marvell,armada-3700-sdhci" + in below. + Please also check property marvell,pad-type in below. + + * For other compatible strings, one register area for Xenon IP. + +Optional Properties: +- marvell,xenon-sdhc-id: + Indicate the corresponding bit index of current SDHC in + SDHC System Operation Control Register Bit[7:0]. + Set/clear the corresponding bit to enable/disable current SDHC. + If Xenon IP contains only one SDHC, this property is optional. + +- marvell,xenon-phy-type: + Xenon support multiple types of PHYs. + To select eMMC 5.1 PHY, set: + marvell,xenon-phy-type = "emmc 5.1 phy" + eMMC 5.1 PHY is the default choice if this property is not provided. + To select eMMC 5.0 PHY, set: + marvell,xenon-phy-type = "emmc 5.0 phy" + + All those types of PHYs can support eMMC, SD and SDIO. + Please note that this property only presents the type of PHY. + It doesn't stand for the entire SDHC type or property. + For example, "emmc 5.1 phy" doesn't mean that this Xenon SDHC only + supports eMMC 5.1. + +- marvell,xenon-phy-znr: + Set PHY ZNR value. + Only available for eMMC PHY. + Valid range = [0:0x1F]. + ZNR is set as 0xF by default if this property is not provided. + +- marvell,xenon-phy-zpr: + Set PHY ZPR value. + Only available for eMMC PHY. + Valid range = [0:0x1F]. + ZPR is set as 0xF by default if this property is not provided. + +- marvell,xenon-phy-nr-success-tun: + Set the number of required consecutive successful sampling points + used to identify a valid sampling window, in tuning process. + Valid range = [1:7]. + Set as 0x4 by default if this property is not provided. + +- marvell,xenon-phy-tun-step-divider: + Set the divider for calculating TUN_STEP. + Set as 64 by default if this property is not provided. + +- marvell,xenon-phy-slow-mode: + If this property is selected, transfers will bypass PHY. + Only available when bus frequency lower than 55MHz in SDR mode. + Disabled by default. Please only try this property if timing issues + always occur with PHY enabled in eMMC HS SDR, SD SDR12, SD SDR25, + SD Default Speed and HS mode and eMMC legacy speed mode. + +- marvell,xenon-tun-count: + Xenon SDHC SoC usually doesn't provide re-tuning counter in + Capabilities Register 3 Bit[11:8]. + This property provides the re-tuning counter. + If this property is not set, default re-tuning counter will + be set as 0x9 in driver. + +- marvell,pad-type: + Type of Armada 3700 SoC PHY PAD Voltage Controller register. + Only valid when "marvell,armada-3700-sdhci" is selected. + Two types: "sd" and "fixed-1-8v". + If "sd" is selected, SoC PHY PAD is set as 3.3V at the beginning and is + switched to 1.8V when later in higher speed mode. + If "fixed-1-8v" is selected, SoC PHY PAD is fixed 1.8V, such as for eMMC. + Please follow the examples with compatible "marvell,armada-3700-sdhci" + in below. + +Example: +- For eMMC: + + sdhci@aa0000 { + compatible = "marvell,armada-ap806-sdhci"; + reg = <0xaa0000 0x1000>; + interrupts = <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH> + clocks = <&emmc_clk>,<&axi_clk>; + clock-names = "core", "axi"; + bus-width = <4>; + marvell,xenon-phy-slow-mode; + marvell,xenon-tun-count = <11>; + non-removable; + no-sd; + no-sdio; + + /* Vmmc and Vqmmc are both fixed */ + }; + +- For SD/SDIO: + + sdhci@ab0000 { + compatible = "marvell,armada-cp110-sdhci"; + reg = <0xab0000 0x1000>; + interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH> + vqmmc-supply = <&sd_vqmmc_regulator>; + vmmc-supply = <&sd_vmmc_regulator>; + clocks = <&sdclk>, <&axi_clk>; + clock-names = "core", "axi"; + bus-width = <4>; + marvell,xenon-tun-count = <9>; + }; + +- For eMMC with compatible "marvell,armada-3700-sdhci": + + sdhci@aa0000 { + compatible = "marvell,armada-3700-sdhci"; + reg = <0xaa0000 0x1000>, + <phy_addr 0x4>; + interrupts = <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH> + clocks = <&emmcclk>; + clock-names = "core"; + bus-width = <8>; + mmc-ddr-1_8v; + mmc-hs400-1_8v; + non-removable; + no-sd; + no-sdio; + + /* Vmmc and Vqmmc are both fixed */ + + marvell,pad-type = "fixed-1-8v"; + }; + +- For SD/SDIO with compatible "marvell,armada-3700-sdhci": + + sdhci@ab0000 { + compatible = "marvell,armada-3700-sdhci"; + reg = <0xab0000 0x1000>, + <phy_addr 0x4>; + interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH> + vqmmc-supply = <&sd_regulator>; + /* Vmmc is fixed */ + clocks = <&sdclk>; + clock-names = "core"; + bus-width = <4>; + + marvell,pad-type = "sd"; + }; |