Merge branch 'topic/namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/broon...
[sfrench/cifs-2.6.git] / Documentation / devicetree / bindings / mtd / mtk-nand.txt
1 MTK SoCs NAND FLASH controller (NFC) DT binding
2
3 This file documents the device tree bindings for MTK SoCs NAND controllers.
4 The functional split of the controller requires two drivers to operate:
5 the nand controller interface driver and the ECC engine driver.
6
7 The hardware description for both devices must be captured as device
8 tree nodes.
9
10 1) NFC NAND Controller Interface (NFI):
11 =======================================
12
13 The first part of NFC is NAND Controller Interface (NFI) HW.
14 Required NFI properties:
15 - compatible:                   Should be one of "mediatek,mt2701-nfc",
16                                 "mediatek,mt2712-nfc".
17 - reg:                          Base physical address and size of NFI.
18 - interrupts:                   Interrupts of NFI.
19 - clocks:                       NFI required clocks.
20 - clock-names:                  NFI clocks internal name.
21 - status:                       Disabled default. Then set "okay" by platform.
22 - ecc-engine:                   Required ECC Engine node.
23 - #address-cells:               NAND chip index, should be 1.
24 - #size-cells:                  Should be 0.
25
26 Example:
27
28         nandc: nfi@1100d000 {
29                 compatible = "mediatek,mt2701-nfc";
30                 reg = <0 0x1100d000 0 0x1000>;
31                 interrupts = <GIC_SPI 56 IRQ_TYPE_LEVEL_LOW>;
32                 clocks = <&pericfg CLK_PERI_NFI>,
33                          <&pericfg CLK_PERI_NFI_PAD>;
34                 clock-names = "nfi_clk", "pad_clk";
35                 status = "disabled";
36                 ecc-engine = <&bch>;
37                 #address-cells = <1>;
38                 #size-cells = <0>;
39         };
40
41 Platform related properties, should be set in {platform_name}.dts:
42 - children nodes:       NAND chips.
43
44 Children nodes properties:
45 - reg:                  Chip Select Signal, default 0.
46                         Set as reg = <0>, <1> when need 2 CS.
47 Optional:
48 - nand-on-flash-bbt:    Store BBT on NAND Flash.
49 - nand-ecc-mode:        the NAND ecc mode (check driver for supported modes)
50 - nand-ecc-step-size:   Number of data bytes covered by a single ECC step.
51                         valid values: 512 and 1024.
52                         1024 is recommended for large page NANDs.
53 - nand-ecc-strength:    Number of bits to correct per ECC step.
54                         The valid values that the controller supports are: 4, 6,
55                         8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36, 40, 44,
56                         48, 52, 56, 60.
57                         The strength should be calculated as follows:
58                         E = (S - F) * 8 / 14
59                         S = O / (P / Q)
60                                 E :     nand-ecc-strength.
61                                 S :     spare size per sector.
62                                 F :     FDM size, should be in the range [1,8].
63                                         It is used to store free oob data.
64                                 O :     oob size.
65                                 P :     page size.
66                                 Q :     nand-ecc-step-size.
67                         If the result does not match any one of the listed
68                         choices above, please select the smaller valid value from
69                         the list.
70                         (otherwise the driver will do the adjustment at runtime)
71 - pinctrl-names:        Default NAND pin GPIO setting name.
72 - pinctrl-0:            GPIO setting node.
73
74 Example:
75         &pio {
76                 nand_pins_default: nanddefault {
77                         pins_dat {
78                                 pinmux = <MT2701_PIN_111_MSDC0_DAT7__FUNC_NLD7>,
79                                          <MT2701_PIN_112_MSDC0_DAT6__FUNC_NLD6>,
80                                          <MT2701_PIN_114_MSDC0_DAT4__FUNC_NLD4>,
81                                          <MT2701_PIN_118_MSDC0_DAT3__FUNC_NLD3>,
82                                          <MT2701_PIN_121_MSDC0_DAT0__FUNC_NLD0>,
83                                          <MT2701_PIN_120_MSDC0_DAT1__FUNC_NLD1>,
84                                          <MT2701_PIN_113_MSDC0_DAT5__FUNC_NLD5>,
85                                          <MT2701_PIN_115_MSDC0_RSTB__FUNC_NLD8>,
86                                          <MT2701_PIN_119_MSDC0_DAT2__FUNC_NLD2>;
87                                 input-enable;
88                                 drive-strength = <MTK_DRIVE_8mA>;
89                                 bias-pull-up;
90                         };
91
92                         pins_we {
93                                 pinmux = <MT2701_PIN_117_MSDC0_CLK__FUNC_NWEB>;
94                                 drive-strength = <MTK_DRIVE_8mA>;
95                                 bias-pull-up = <MTK_PUPD_SET_R1R0_10>;
96                         };
97
98                         pins_ale {
99                                 pinmux = <MT2701_PIN_116_MSDC0_CMD__FUNC_NALE>;
100                                 drive-strength = <MTK_DRIVE_8mA>;
101                                 bias-pull-down = <MTK_PUPD_SET_R1R0_10>;
102                         };
103                 };
104         };
105
106         &nandc {
107                 status = "okay";
108                 pinctrl-names = "default";
109                 pinctrl-0 = <&nand_pins_default>;
110                 nand@0 {
111                         reg = <0>;
112                         nand-on-flash-bbt;
113                         nand-ecc-mode = "hw";
114                         nand-ecc-strength = <24>;
115                         nand-ecc-step-size = <1024>;
116                 };
117         };
118
119 NAND chip optional subnodes:
120 - Partitions, see Documentation/devicetree/bindings/mtd/partition.txt
121
122 Example:
123         nand@0 {
124                 partitions {
125                         compatible = "fixed-partitions";
126                         #address-cells = <1>;
127                         #size-cells = <1>;
128
129                         preloader@0 {
130                                 label = "pl";
131                                 read-only;
132                                 reg = <0x00000000 0x00400000>;
133                         };
134                         android@0x00400000 {
135                                 label = "android";
136                                 reg = <0x00400000 0x12c00000>;
137                         };
138                 };
139         };
140
141 2) ECC Engine:
142 ==============
143
144 Required BCH properties:
145 - compatible:   Should be one of "mediatek,mt2701-ecc", "mediatek,mt2712-ecc".
146 - reg:          Base physical address and size of ECC.
147 - interrupts:   Interrupts of ECC.
148 - clocks:       ECC required clocks.
149 - clock-names:  ECC clocks internal name.
150 - status:       Disabled default. Then set "okay" by platform.
151
152 Example:
153
154         bch: ecc@1100e000 {
155                 compatible = "mediatek,mt2701-ecc";
156                 reg = <0 0x1100e000 0 0x1000>;
157                 interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_LOW>;
158                 clocks = <&pericfg CLK_PERI_NFI_ECC>;
159                 clock-names = "nfiecc_clk";
160                 status = "disabled";
161         };