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diff --git a/Documentation/devicetree/bindings/mtd/mtk-nand.txt b/Documentation/devicetree/bindings/mtd/mtk-nand.txt new file mode 100644 index 000000000..4d3ec5e4f --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/mtk-nand.txt @@ -0,0 +1,176 @@ +MTK SoCs NAND FLASH controller (NFC) DT binding + +This file documents the device tree bindings for MTK SoCs NAND controllers. +The functional split of the controller requires two drivers to operate: +the nand controller interface driver and the ECC engine driver. + +The hardware description for both devices must be captured as device +tree nodes. + +1) NFC NAND Controller Interface (NFI): +======================================= + +The first part of NFC is NAND Controller Interface (NFI) HW. +Required NFI properties: +- compatible: Should be one of + "mediatek,mt2701-nfc", + "mediatek,mt2712-nfc", + "mediatek,mt7622-nfc". +- reg: Base physical address and size of NFI. +- interrupts: Interrupts of NFI. +- clocks: NFI required clocks. +- clock-names: NFI clocks internal name. +- ecc-engine: Required ECC Engine node. +- #address-cells: NAND chip index, should be 1. +- #size-cells: Should be 0. + +Example: + + nandc: nfi@1100d000 { + compatible = "mediatek,mt2701-nfc"; + reg = <0 0x1100d000 0 0x1000>; + interrupts = <GIC_SPI 56 IRQ_TYPE_LEVEL_LOW>; + clocks = <&pericfg CLK_PERI_NFI>, + <&pericfg CLK_PERI_NFI_PAD>; + clock-names = "nfi_clk", "pad_clk"; + ecc-engine = <&bch>; + #address-cells = <1>; + #size-cells = <0>; + }; + +Platform related properties, should be set in {platform_name}.dts: +- children nodes: NAND chips. + +Children nodes properties: +- reg: Chip Select Signal, default 0. + Set as reg = <0>, <1> when need 2 CS. +Optional: +- nand-on-flash-bbt: Store BBT on NAND Flash. +- nand-ecc-mode: the NAND ecc mode (check driver for supported modes) +- nand-ecc-step-size: Number of data bytes covered by a single ECC step. + valid values: + 512 and 1024 on mt2701 and mt2712. + 512 only on mt7622. + 1024 is recommended for large page NANDs. +- nand-ecc-strength: Number of bits to correct per ECC step. + The valid values that each controller supports: + mt2701: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, + 32, 36, 40, 44, 48, 52, 56, 60. + mt2712: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, + 32, 36, 40, 44, 48, 52, 56, 60, 68, 72, 80. + mt7622: 4, 6, 8, 10, 12, 14, 16. + The strength should be calculated as follows: + E = (S - F) * 8 / B + S = O / (P / Q) + E : nand-ecc-strength. + S : spare size per sector. + F : FDM size, should be in the range [1,8]. + It is used to store free oob data. + O : oob size. + P : page size. + Q : nand-ecc-step-size. + B : number of parity bits needed to correct + 1 bitflip. + According to MTK NAND controller design, + this number depends on max ecc step size + that MTK NAND controller supports. + If max ecc step size supported is 1024, + then it should be always 14. And if max + ecc step size is 512, then it should be + always 13. + If the result does not match any one of the listed + choices above, please select the smaller valid value from + the list. + (otherwise the driver will do the adjustment at runtime) +- pinctrl-names: Default NAND pin GPIO setting name. +- pinctrl-0: GPIO setting node. + +Example: + &pio { + nand_pins_default: nanddefault { + pins_dat { + pinmux = <MT2701_PIN_111_MSDC0_DAT7__FUNC_NLD7>, + <MT2701_PIN_112_MSDC0_DAT6__FUNC_NLD6>, + <MT2701_PIN_114_MSDC0_DAT4__FUNC_NLD4>, + <MT2701_PIN_118_MSDC0_DAT3__FUNC_NLD3>, + <MT2701_PIN_121_MSDC0_DAT0__FUNC_NLD0>, + <MT2701_PIN_120_MSDC0_DAT1__FUNC_NLD1>, + <MT2701_PIN_113_MSDC0_DAT5__FUNC_NLD5>, + <MT2701_PIN_115_MSDC0_RSTB__FUNC_NLD8>, + <MT2701_PIN_119_MSDC0_DAT2__FUNC_NLD2>; + input-enable; + drive-strength = <MTK_DRIVE_8mA>; + bias-pull-up; + }; + + pins_we { + pinmux = <MT2701_PIN_117_MSDC0_CLK__FUNC_NWEB>; + drive-strength = <MTK_DRIVE_8mA>; + bias-pull-up = <MTK_PUPD_SET_R1R0_10>; + }; + + pins_ale { + pinmux = <MT2701_PIN_116_MSDC0_CMD__FUNC_NALE>; + drive-strength = <MTK_DRIVE_8mA>; + bias-pull-down = <MTK_PUPD_SET_R1R0_10>; + }; + }; + }; + + &nandc { + status = "okay"; + pinctrl-names = "default"; + pinctrl-0 = <&nand_pins_default>; + nand@0 { + reg = <0>; + nand-on-flash-bbt; + nand-ecc-mode = "hw"; + nand-ecc-strength = <24>; + nand-ecc-step-size = <1024>; + }; + }; + +NAND chip optional subnodes: +- Partitions, see Documentation/devicetree/bindings/mtd/partition.txt + +Example: + nand@0 { + partitions { + compatible = "fixed-partitions"; + #address-cells = <1>; + #size-cells = <1>; + + preloader@0 { + label = "pl"; + read-only; + reg = <0x00000000 0x00400000>; + }; + android@00400000 { + label = "android"; + reg = <0x00400000 0x12c00000>; + }; + }; + }; + +2) ECC Engine: +============== + +Required BCH properties: +- compatible: Should be one of + "mediatek,mt2701-ecc", + "mediatek,mt2712-ecc", + "mediatek,mt7622-ecc". +- reg: Base physical address and size of ECC. +- interrupts: Interrupts of ECC. +- clocks: ECC required clocks. +- clock-names: ECC clocks internal name. + +Example: + + bch: ecc@1100e000 { + compatible = "mediatek,mt2701-ecc"; + reg = <0 0x1100e000 0 0x1000>; + interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_LOW>; + clocks = <&pericfg CLK_PERI_NFI_ECC>; + clock-names = "nfiecc_clk"; + }; |