mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
112 lines
3.8 KiB
112 lines
3.8 KiB
Device tree bindings for i.MX Wireless External Interface Module (WEIM) |
|
|
|
The term "wireless" does not imply that the WEIM is literally an interface |
|
without wires. It simply means that this module was originally designed for |
|
wireless and mobile applications that use low-power technology. |
|
|
|
The actual devices are instantiated from the child nodes of a WEIM node. |
|
|
|
Required properties: |
|
|
|
- compatible: Should contain one of the following: |
|
"fsl,imx1-weim" |
|
"fsl,imx27-weim" |
|
"fsl,imx51-weim" |
|
"fsl,imx50-weim" |
|
"fsl,imx6q-weim" |
|
- reg: A resource specifier for the register space |
|
(see the example below) |
|
- clocks: the clock, see the example below. |
|
- #address-cells: Must be set to 2 to allow memory address translation |
|
- #size-cells: Must be set to 1 to allow CS address passing |
|
- ranges: Must be set up to reflect the memory layout with four |
|
integer values for each chip-select line in use: |
|
|
|
<cs-number> 0 <physical address of mapping> <size> |
|
|
|
Optional properties: |
|
|
|
- fsl,weim-cs-gpr: For "fsl,imx50-weim" and "fsl,imx6q-weim" type of |
|
devices, it should be the phandle to the system General |
|
Purpose Register controller that contains WEIM CS GPR |
|
register, e.g. IOMUXC_GPR1 on i.MX6Q. IOMUXC_GPR1[11:0] |
|
should be set up as one of the following 4 possible |
|
values depending on the CS space configuration. |
|
|
|
IOMUXC_GPR1[11:0] CS0 CS1 CS2 CS3 |
|
--------------------------------------------- |
|
05 128M 0M 0M 0M |
|
033 64M 64M 0M 0M |
|
0113 64M 32M 32M 0M |
|
01111 32M 32M 32M 32M |
|
|
|
In case that the property is absent, the reset value or |
|
what bootloader sets up in IOMUXC_GPR1[11:0] will be |
|
used. |
|
|
|
- fsl,burst-clk-enable For "fsl,imx50-weim" and "fsl,imx6q-weim" type of |
|
devices, the presence of this property indicates that |
|
the weim bus should operate in Burst Clock Mode. |
|
|
|
Timing property for child nodes. It is mandatory, not optional. |
|
|
|
- fsl,weim-cs-timing: The timing array, contains timing values for the |
|
child node. We get the CS indexes from the address |
|
ranges in the child node's "reg" property. |
|
The number of registers depends on the selected chip: |
|
For i.MX1, i.MX21 ("fsl,imx1-weim") there are two |
|
registers: CSxU, CSxL. |
|
For i.MX25, i.MX27, i.MX31 and i.MX35 ("fsl,imx27-weim") |
|
there are three registers: CSCRxU, CSCRxL, CSCRxA. |
|
For i.MX50, i.MX53 ("fsl,imx50-weim"), |
|
i.MX51 ("fsl,imx51-weim") and i.MX6Q ("fsl,imx6q-weim") |
|
there are six registers: CSxGCR1, CSxGCR2, CSxRCR1, |
|
CSxRCR2, CSxWCR1, CSxWCR2. |
|
|
|
Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM: |
|
|
|
weim: weim@21b8000 { |
|
compatible = "fsl,imx6q-weim"; |
|
reg = <0x021b8000 0x4000>; |
|
clocks = <&clks 196>; |
|
#address-cells = <2>; |
|
#size-cells = <1>; |
|
ranges = <0 0 0x08000000 0x08000000>; |
|
fsl,weim-cs-gpr = <&gpr>; |
|
|
|
nor@0,0 { |
|
compatible = "cfi-flash"; |
|
reg = <0 0 0x02000000>; |
|
#address-cells = <1>; |
|
#size-cells = <1>; |
|
bank-width = <2>; |
|
fsl,weim-cs-timing = <0x00620081 0x00000001 0x1c022000 |
|
0x0000c000 0x1404a38e 0x00000000>; |
|
}; |
|
}; |
|
|
|
Example for an imx6q-based board, a multi-chipselect device connected to WEIM: |
|
|
|
In this case, both chip select 0 and 1 will be configured with the same timing |
|
array values. |
|
|
|
weim: weim@21b8000 { |
|
compatible = "fsl,imx6q-weim"; |
|
reg = <0x021b8000 0x4000>; |
|
clocks = <&clks 196>; |
|
#address-cells = <2>; |
|
#size-cells = <1>; |
|
ranges = <0 0 0x08000000 0x02000000 |
|
1 0 0x0a000000 0x02000000 |
|
2 0 0x0c000000 0x02000000 |
|
3 0 0x0e000000 0x02000000>; |
|
fsl,weim-cs-gpr = <&gpr>; |
|
|
|
acme@0 { |
|
compatible = "acme,whatever"; |
|
reg = <0 0 0x100>, <0 0x400000 0x800>, |
|
<1 0x400000 0x800>; |
|
fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100 |
|
0x00000000 0xa0000240 0x00000000>; |
|
}; |
|
};
|
|
|