summaryrefslogtreecommitdiffstats
path: root/dts/Bindings/clock/actions,s900-cmu.txt
diff options
context:
space:
mode:
authorSascha Hauer <s.hauer@pengutronix.de>2018-06-21 13:44:30 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2018-06-22 08:16:13 +0200
commite4067b75fb6ca83a58b2c342a0b3ee12e1223c4e (patch)
treebe013bf46292f4696ac776bc91c1cf35b7adab24 /dts/Bindings/clock/actions,s900-cmu.txt
parentfe040e0977fab29216f5039e8f9b04e6dbec859a (diff)
downloadbarebox-e4067b75fb6ca83a58b2c342a0b3ee12e1223c4e.tar.gz
barebox-e4067b75fb6ca83a58b2c342a0b3ee12e1223c4e.tar.xz
dts: update to v4.18-rc1
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'dts/Bindings/clock/actions,s900-cmu.txt')
-rw-r--r--dts/Bindings/clock/actions,s900-cmu.txt47
1 files changed, 47 insertions, 0 deletions
diff --git a/dts/Bindings/clock/actions,s900-cmu.txt b/dts/Bindings/clock/actions,s900-cmu.txt
new file mode 100644
index 0000000000..93e4fb827c
--- /dev/null
+++ b/dts/Bindings/clock/actions,s900-cmu.txt
@@ -0,0 +1,47 @@
+* Actions S900 Clock Management Unit (CMU)
+
+The Actions S900 clock management unit generates and supplies clock to various
+controllers within the SoC. The clock binding described here is applicable to
+S900 SoC.
+
+Required Properties:
+
+- compatible: should be "actions,s900-cmu"
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- clocks: Reference to the parent clocks ("hosc", "losc")
+- #clock-cells: should be 1.
+
+Each clock is assigned an identifier, and client nodes can use this identifier
+to specify the clock which they consume.
+
+All available clocks are defined as preprocessor macros in
+dt-bindings/clock/actions,s900-cmu.h header and can be used in device
+tree sources.
+
+External clocks:
+
+The hosc clock used as input for the plls is generated outside the SoC. It is
+expected that it is defined using standard clock bindings as "hosc".
+
+Actions S900 CMU also requires one more clock:
+ - "losc" - internal low frequency oscillator
+
+Example: Clock Management Unit node:
+
+ cmu: clock-controller@e0160000 {
+ compatible = "actions,s900-cmu";
+ reg = <0x0 0xe0160000 0x0 0x1000>;
+ clocks = <&hosc>, <&losc>;
+ #clock-cells = <1>;
+ };
+
+Example: UART controller node that consumes clock generated by the clock
+management unit:
+
+ uart: serial@e012a000 {
+ compatible = "actions,s900-uart", "actions,owl-uart";
+ reg = <0x0 0xe012a000 0x0 0x2000>;
+ interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&cmu CLK_UART5>;
+ };