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authorShawn Guo <shawn.guo@linaro.org>2014-02-11 09:52:09 +0800
committerShawn Guo <shawn.guo@linaro.org>2014-03-05 10:40:46 +0800
commit8d9ee21e98205eebc7fc6caf08a764c9e12c7d68 (patch)
tree36a738878f16ced02eabf99440a2effab9063f8f /Documentation/devicetree
parent7899d7d5789653511f19f02ff6819f8c330018fc (diff)
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bus: imx-weim: support CS GPR configuration
For imx50-weim and imx6q-weim type of devices, there might a WEIM CS space configuration register in General Purpose Register controller, e.g. IOMUXC_GPR1 on i.MX6Q. Depending on which configuration of the following 4 is chosen for given system, IOMUXC_GPR1[11:0] should be set up as 05, 033, 0113 or 01111 correspondingly. CS0(128M) CS1(0M) CS2(0M) CS3(0M) CS0(64M) CS1(64M) CS2(0M) CS3(0M) CS0(64M) CS1(32M) CS2(32M) CS3(0M) CS0(32M) CS1(32M) CS2(32M) CS3(32M) The patch creates a function for such type of devices, which scans 'ranges' property of WEIM node and build the GPR value incrementally. Thus the WEIM CS GPR can be set up automatically at boot time. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Reviewed-by: Philippe De Muyter <phdm@macqel.be> Tested-by: Philippe De Muyter <phdm@macqel.be>
Diffstat (limited to 'Documentation/devicetree')
-rw-r--r--Documentation/devicetree/bindings/bus/imx-weim.txt28
1 files changed, 27 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/bus/imx-weim.txt b/Documentation/devicetree/bindings/bus/imx-weim.txt
index 0fd76c405208..6630d842c7a3 100644
--- a/Documentation/devicetree/bindings/bus/imx-weim.txt
+++ b/Documentation/devicetree/bindings/bus/imx-weim.txt
@@ -8,7 +8,12 @@ The actual devices are instantiated from the child nodes of a WEIM node.
Required properties:
- - compatible: Should be set to "fsl,<soc>-weim"
+ - 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.
@@ -19,6 +24,26 @@ Required properties:
<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.
+
Timing property for child nodes. It is mandatory, not optional.
- fsl,weim-cs-timing: The timing array, contains timing values for the
@@ -43,6 +68,7 @@ Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM:
#address-cells = <2>;
#size-cells = <1>;
ranges = <0 0 0x08000000 0x08000000>;
+ fsl,weim-cs-gpr = <&gpr>;
nor@0,0 {
compatible = "cfi-flash";