1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
* Ingenic JZ4780 NAND/ECC
This file documents the device tree bindings for NAND flash devices on the
JZ4780. NAND devices are connected to the NEMC controller (described in
memory-controllers/ingenic,jz4780-nemc.txt), and thus NAND device nodes must
be children of the NEMC node.
Required NAND controller device properties:
- compatible: Should be one of:
* ingenic,jz4740-nand
* ingenic,jz4725b-nand
* ingenic,jz4780-nand
- reg: For each bank with a NAND chip attached, should specify a bank number,
an offset of 0 and a size of 0x1000000 (i.e. the whole NEMC bank).
Optional NAND controller device properties:
- ecc-engine: To make use of the hardware ECC controller, this
property must contain a phandle for the ECC controller node. The required
properties for this node are described below. If this is not specified,
software ECC will be used instead.
Optional children nodes:
- Individual NAND chips are children of the NAND controller node.
Required children node properties:
- reg: An integer ranging from 1 to 6 representing the CS line to use.
Optional children node properties:
- nand-ecc-step-size: ECC block size in bytes.
- nand-ecc-strength: ECC strength (max number of correctable bits).
- nand-ecc-mode: String, operation mode of the NAND ecc mode. "hw" by default
- nand-on-flash-bbt: boolean to enable on flash bbt option, if not present false
- rb-gpios: GPIO specifier for the busy pin.
- wp-gpios: GPIO specifier for the write protect pin.
Optional child node of NAND chip nodes:
- partitions: see Documentation/devicetree/bindings/mtd/partition.txt
Example:
nemc: nemc@13410000 {
...
nandc: nand-controller@1 {
compatible = "ingenic,jz4780-nand";
reg = <1 0 0x1000000>; /* Bank 1 */
#address-cells = <1>;
#size-cells = <0>;
ecc-engine = <&bch>;
nand@1 {
reg = <1>;
nand-ecc-step-size = <1024>;
nand-ecc-strength = <24>;
nand-ecc-mode = "hw";
nand-on-flash-bbt;
rb-gpios = <&gpa 20 GPIO_ACTIVE_LOW>;
wp-gpios = <&gpf 22 GPIO_ACTIVE_LOW>;
partitions {
#address-cells = <2>;
#size-cells = <2>;
...
}
};
};
};
The ECC controller is a separate SoC component used for error correction on
NAND devices. The following is a description of the device properties for a
ECC controller.
Required ECC properties:
- compatible: Should be one of:
* ingenic,jz4740-ecc
* ingenic,jz4725b-bch
* ingenic,jz4780-bch
- reg: Should specify the ECC controller registers location and length.
- clocks: Clock for the ECC controller.
Example:
bch: bch@134d0000 {
compatible = "ingenic,jz4780-bch";
reg = <0x134d0000 0x10000>;
clocks = <&cgu JZ4780_CLK_BCH>;
};
|