exynos-dw-mshc.txt (3874B)
1* Samsung Exynos specific extensions to the Synopsys Designware Mobile 2 Storage Host Controller 3 4The Synopsys designware mobile storage host controller is used to interface 5a SoC with storage medium such as eMMC or SD/MMC cards. This file documents 6differences between the core Synopsys dw mshc controller properties described 7by synopsys-dw-mshc.txt and the properties used by the Samsung Exynos specific 8extensions to the Synopsys Designware Mobile Storage Host Controller. 9 10Required Properties: 11 12* compatible: should be 13 - "samsung,exynos4210-dw-mshc": for controllers with Samsung Exynos4210 14 specific extensions. 15 - "samsung,exynos4412-dw-mshc": for controllers with Samsung Exynos4412 16 specific extensions. 17 - "samsung,exynos5250-dw-mshc": for controllers with Samsung Exynos5250 18 specific extensions. 19 - "samsung,exynos5420-dw-mshc": for controllers with Samsung Exynos5420 20 specific extensions. 21 - "samsung,exynos7-dw-mshc": for controllers with Samsung Exynos7 22 specific extensions. 23 - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7 24 specific extensions having an SMU. 25 - "axis,artpec8-dw-mshc": for controllers with ARTPEC-8 specific 26 extensions. 27 28* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface 29 unit (ciu) clock. This property is applicable only for Exynos5 SoC's and 30 ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7. 31 32* samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value 33 in transmit mode and CIU clock phase shift value in receive mode for single 34 data rate mode operation. Refer notes below for the order of the cells and the 35 valid values. 36 37* samsung,dw-mshc-ddr-timing: Specifies the value of CUI clock phase shift value 38 in transmit mode and CIU clock phase shift value in receive mode for double 39 data rate mode operation. Refer notes below for the order of the cells and the 40 valid values. 41* samsung,dw-mshc-hs400-timing: Specifies the value of CIU TX and RX clock phase 42 shift value for hs400 mode operation. 43 44 Notes for the sdr-timing and ddr-timing values: 45 46 The order of the cells should be 47 - First Cell: CIU clock phase shift value for tx mode. 48 - Second Cell: CIU clock phase shift value for rx mode. 49 50 Valid values for SDR and DDR CIU clock timing for Exynos5250: 51 - valid value for tx phase shift and rx phase shift is 0 to 7. 52 - when CIU clock divider value is set to 3, all possible 8 phase shift 53 values can be used. 54 - if CIU clock divider value is 0 (that is divide by 1), both tx and rx 55 phase shift clocks should be 0. 56 57* samsung,read-strobe-delay: RCLK (Data strobe) delay to control HS400 mode 58 (Latency value for delay line in Read path) 59 60Required properties for a slot (Deprecated - Recommend to use one slot per host): 61 62* gpios: specifies a list of gpios used for command, clock and data bus. The 63 first gpio is the command line and the second gpio is the clock line. The 64 rest of the gpios (depending on the bus-width property) are the data lines in 65 no particular order. The format of the gpio specifier depends on the gpio 66 controller. 67(Deprecated - Refer to Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt) 68 69Example: 70 71 The MSHC controller node can be split into two portions, SoC specific and 72 board specific portions as listed below. 73 74 dwmmc0@12200000 { 75 compatible = "samsung,exynos5250-dw-mshc"; 76 reg = <0x12200000 0x1000>; 77 interrupts = <0 75 0>; 78 #address-cells = <1>; 79 #size-cells = <0>; 80 }; 81 82 dwmmc0@12200000 { 83 cap-mmc-highspeed; 84 cap-sd-highspeed; 85 broken-cd; 86 fifo-depth = <0x80>; 87 card-detect-delay = <200>; 88 samsung,dw-mshc-ciu-div = <3>; 89 samsung,dw-mshc-sdr-timing = <2 3>; 90 samsung,dw-mshc-ddr-timing = <1 2>; 91 samsung,dw-mshc-hs400-timing = <0 2>; 92 samsung,read-strobe-delay = <90>; 93 bus-width = <8>; 94 };