[PATCH v4 1/2] mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND

Jorge Ramirez-Ortiz
2016-04-29T16:17:51Z

This patch adds documentation support for Smart Device Gen1 type of
NAND controllers.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
---
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 = <GIC_SPI 56 IRQ_TYPE_LEVEL_LOW>;
+ 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 = <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@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 = <GIC_SPI 55 IRQ_TYPE_LEVEL_LOW>;
+ clocks = <&pericfg CLK_PERI_NFI_ECC>;
+ clock-names = "nfiecc_clk";
+ status = "disabled";
+ };
--
2.7.4