diff options
author | Stefan Roese <sr@denx.de> | 2009-04-16 17:11:54 -0400 |
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committer | Grant Likely <grant.likely@secretlab.ca> | 2009-04-16 17:11:54 -0400 |
commit | efcc2da3fd148c9acb7d7cf1d9800e0649f950fc (patch) | |
tree | 99c93da3639a22d3ac487c575425f7a0c46d2826 /Documentation/powerpc/dts-bindings/mtd-physmap.txt | |
parent | 412401029259b1ad67559cec93bcc7ee4a9551aa (diff) |
powerpc/of-device-tree: Factor MTD physmap bindings out of booting-without-of
It's easier to find bindings descriptions in separate files. So factor
out the MTD physmap bindings into a separate file to not clutter
booting-without-of.txt more.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'Documentation/powerpc/dts-bindings/mtd-physmap.txt')
-rw-r--r-- | Documentation/powerpc/dts-bindings/mtd-physmap.txt | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/Documentation/powerpc/dts-bindings/mtd-physmap.txt b/Documentation/powerpc/dts-bindings/mtd-physmap.txt new file mode 100644 index 000000000000..cd474f9aef39 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/mtd-physmap.txt | |||
@@ -0,0 +1,63 @@ | |||
1 | CFI or JEDEC memory-mapped NOR flash | ||
2 | |||
3 | Flash chips (Memory Technology Devices) are often used for solid state | ||
4 | file systems on embedded devices. | ||
5 | |||
6 | - compatible : should contain the specific model of flash chip(s) | ||
7 | used, if known, followed by either "cfi-flash" or "jedec-flash" | ||
8 | - reg : Address range of the flash chip | ||
9 | - bank-width : Width (in bytes) of the flash bank. Equal to the | ||
10 | device width times the number of interleaved chips. | ||
11 | - device-width : (optional) Width of a single flash chip. If | ||
12 | omitted, assumed to be equal to 'bank-width'. | ||
13 | - #address-cells, #size-cells : Must be present if the flash has | ||
14 | sub-nodes representing partitions (see below). In this case | ||
15 | both #address-cells and #size-cells must be equal to 1. | ||
16 | |||
17 | For JEDEC compatible devices, the following additional properties | ||
18 | are defined: | ||
19 | |||
20 | - vendor-id : Contains the flash chip's vendor id (1 byte). | ||
21 | - device-id : Contains the flash chip's device id (1 byte). | ||
22 | |||
23 | In addition to the information on the flash bank itself, the | ||
24 | device tree may optionally contain additional information | ||
25 | describing partitions of the flash address space. This can be | ||
26 | used on platforms which have strong conventions about which | ||
27 | portions of the flash are used for what purposes, but which don't | ||
28 | use an on-flash partition table such as RedBoot. | ||
29 | |||
30 | Each partition is represented as a sub-node of the flash device. | ||
31 | Each node's name represents the name of the corresponding | ||
32 | partition of the flash device. | ||
33 | |||
34 | Flash partitions | ||
35 | - reg : The partition's offset and size within the flash bank. | ||
36 | - label : (optional) The label / name for this flash partition. | ||
37 | If omitted, the label is taken from the node name (excluding | ||
38 | the unit address). | ||
39 | - read-only : (optional) This parameter, if present, is a hint to | ||
40 | Linux that this flash partition should only be mounted | ||
41 | read-only. This is usually used for flash partitions | ||
42 | containing early-boot firmware images or data which should not | ||
43 | be clobbered. | ||
44 | |||
45 | Example: | ||
46 | |||
47 | flash@ff000000 { | ||
48 | compatible = "amd,am29lv128ml", "cfi-flash"; | ||
49 | reg = <ff000000 01000000>; | ||
50 | bank-width = <4>; | ||
51 | device-width = <1>; | ||
52 | #address-cells = <1>; | ||
53 | #size-cells = <1>; | ||
54 | fs@0 { | ||
55 | label = "fs"; | ||
56 | reg = <0 f80000>; | ||
57 | }; | ||
58 | firmware@f80000 { | ||
59 | label ="firmware"; | ||
60 | reg = <f80000 80000>; | ||
61 | read-only; | ||
62 | }; | ||
63 | }; | ||