From 5e1c00983efeca4522ac2e8574e3e3997d26a203 Mon Sep 17 00:00:00 2001 From: Jorge Ramirez-Ortiz Date: Fri, 29 Apr 2016 12:17:21 -0400 Subject: [PATCH 074/102] mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND This patch adds documentation support for Smart Device Gen1 type of NAND controllers. Signed-off-by: Jorge Ramirez-Ortiz --- Documentation/devicetree/bindings/mtd/mtk-nand.txt | 161 ++++++++++++++++++++ 1 file changed, 161 insertions(+) create mode 100644 Documentation/devicetree/bindings/mtd/mtk-nand.txt diff --git a/Documentation/devicetree/bindings/mtd/mtk-nand.txt b/Documentation/devicetree/bindings/mtd/mtk-nand.txt new file mode 100644 index 0000000..175767d --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/mtk-nand.txt @@ -0,0 +1,161 @@ +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 "mediatek,mtxxxx-nfc". +- reg: Base physical address and size of NFI. +- interrupts: Interrupts of NFI. +- clocks: NFI required clocks. +- clock-names: NFI clocks internal name. +- status: Disabled default. Then set "okay" by platform. +- 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 = ; + clocks = <&pericfg CLK_PERI_NFI>, + <&pericfg CLK_PERI_NFI_PAD>; + clock-names = "nfi_clk", "pad_clk"; + status = "disabled"; + 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. + The controller only supports 512 and 1024. + For large page NANDs ther recommended value is 1024. +- nand-ecc-strength: Number of bits to correct per ECC step. + The valid values that the controller supports are: 4, 6, + 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36, 40, 44, + 48, 52, 56, 60. + The strength should be calculated as follows: + E = (S - F) * 8 / 14 + 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 + 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 clamping at runtime). +- vmch-supply: NAND power supply. +- pinctrl-names: Default NAND pin GPIO setting name. +- pinctrl-0: GPIO setting node. + +Example: + &pio { + nand_pins_default: nanddefault { + pins_dat { + pinmux = , + , + , + , + , + , + , + , + ; + input-enable; + drive-strength = ; + bias-pull-up; + }; + + pins_we { + pinmux = ; + drive-strength = ; + bias-pull-up = ; + }; + + pins_ale { + pinmux = ; + drive-strength = ; + bias-pull-down = ; + }; + }; + }; + + &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@0x00400000 { + label = "android"; + reg = <0x00400000 0x12c00000>; + }; + }; + }; + +2) ECC Engine: +============== + +Required BCH properties: +- compatible: Should be "mediatek,mtxxxx-ecc". +- reg: Base physical address and size of ECC. +- interrupts: Interrupts of ECC. +- clocks: ECC required clocks. +- clock-names: ECC clocks internal name. +- status: Disabled default. Then set "okay" by platform. + +Example: + + bch: ecc@1100e000 { + compatible = "mediatek,mt2701-ecc"; + reg = <0 0x1100e000 0 0x1000>; + interrupts = ; + clocks = <&pericfg CLK_PERI_NFI_ECC>; + clock-names = "nfiecc_clk"; + status = "disabled"; + }; -- 1.7.10.4