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-rw-r--r--Documentation/devicetree/bindings/chosen.txt46
-rw-r--r--Documentation/devicetree/bindings/serial/pl011.txt28
-rw-r--r--Documentation/devicetree/bindings/unittest.txt14
3 files changed, 85 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt
new file mode 100644
index 000000000000..ed838f453f7a
--- /dev/null
+++ b/Documentation/devicetree/bindings/chosen.txt
@@ -0,0 +1,46 @@
+The chosen node
+---------------
+
+The chosen node does not represent a real device, but serves as a place
+for passing data between firmware and the operating system, like boot
+arguments. Data in the chosen node does not represent the hardware.
+
+
+stdout-path property
+--------------------
+
+Device trees may specify the device to be used for boot console output
+with a stdout-path property under /chosen, as described in ePAPR, e.g.
+
+/ {
+ chosen {
+ stdout-path = "/serial@f00:115200";
+ };
+
+ serial@f00 {
+ compatible = "vendor,some-uart";
+ reg = <0xf00 0x10>;
+ };
+};
+
+If the character ":" is present in the value, this terminates the path.
+The meaning of any characters following the ":" is device-specific, and
+must be specified in the relevant binding documentation.
+
+For UART devices, the preferred binding is a string in the form:
+
+ <baud>{<parity>{<bits>{<flow>}}}
+
+where
+
+ baud - baud rate in decimal
+ parity - 'n' (none), 'o', (odd) or 'e' (even)
+ bits - number of data bits
+ flow - 'r' (rts)
+
+For example: 115200n8r
+
+Implementation note: Linux will look for the property "linux,stdout-path" or
+on PowerPC "stdout" if "stdout-path" is not found. However, the
+"linux,stdout-path" and "stdout" properties are deprecated. New platforms
+should only use the "stdout-path" property.
diff --git a/Documentation/devicetree/bindings/serial/pl011.txt b/Documentation/devicetree/bindings/serial/pl011.txt
index 5d2e840ae65c..52464918cfe2 100644
--- a/Documentation/devicetree/bindings/serial/pl011.txt
+++ b/Documentation/devicetree/bindings/serial/pl011.txt
@@ -6,12 +6,34 @@ Required properties:
- interrupts: exactly one interrupt specifier
Optional properties:
-- pinctrl: When present, must have one state named "sleep"
- and one state named "default"
-- clocks: When present, must refer to exactly one clock named
+- pinctrl: When present, must have one state named "default",
+ and may contain a second name named "sleep". The former
+ state sets up pins for ordinary operation whereas
+ the latter state will put the associated pins to sleep
+ when the UART is unused
+- clocks: When present, the first clock listed must correspond to
+ the clock named UARTCLK on the IP block, i.e. the clock
+ to the external serial line, whereas the second clock
+ must correspond to the PCLK clocking the internal logic
+ of the block. Just listing one clock (the first one) is
+ deprecated.
+- clocks-names: When present, the first clock listed must be named
+ "uartclk" and the second clock listed must be named
"apb_pclk"
- dmas: When present, may have one or two dma channels.
The first one must be named "rx", the second one
must be named "tx".
See also bindings/arm/primecell.txt
+
+Example:
+
+uart@80120000 {
+ compatible = "arm,pl011", "arm,primecell";
+ reg = <0x80120000 0x1000>;
+ interrupts = <0 11 IRQ_TYPE_LEVEL_HIGH>;
+ dmas = <&dma 13 0 0x2>, <&dma 13 0 0x0>;
+ dma-names = "rx", "tx";
+ clocks = <&foo_clk>, <&bar_clk>;
+ clock-names = "uartclk", "apb_pclk";
+};
diff --git a/Documentation/devicetree/bindings/unittest.txt b/Documentation/devicetree/bindings/unittest.txt
new file mode 100644
index 000000000000..0f92a22fddfa
--- /dev/null
+++ b/Documentation/devicetree/bindings/unittest.txt
@@ -0,0 +1,14 @@
+* OF selftest platform device
+
+** selftest
+
+Required properties:
+- compatible: must be "selftest"
+
+All other properties are optional.
+
+Example:
+ selftest {
+ compatible = "selftest";
+ status = "okay";
+ };