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authorMike Marshall <hubcap@omnibond.com>2016-03-14 15:39:42 -0400
committerMike Marshall <hubcap@omnibond.com>2016-03-14 15:39:42 -0400
commitab6652524aaf834d5dcdb46dd7695813b8d63da5 (patch)
treebb3876a9b61254be902416f7dbf578deb28e9f22 /Documentation/devicetree/bindings/clock/arm-syscon-icst.txt
parentacfcbaf1925f2dc5c46c61de69d756dec92a2ff8 (diff)
parentb562e44f507e863c6792946e4e1b1449fbbac85d (diff)
Orangefs: merge to v4.5
Merge tag 'v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into current Linux 4.5
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+ARM System Controller ICST clocks
+
+The ICS525 and ICS307 oscillators are produced by Integrated Devices
+Technology (IDT). ARM integrated these oscillators deeply into their
+reference designs by adding special control registers that manage such
+oscillators to their system controllers.
+
+The ARM system controller contains logic to serialize and initialize
+an ICST clock request after a write to the 32 bit register at an offset
+into the system controller. Furthermore, to even be able to alter one of
+these frequencies, the system controller must first be unlocked by
+writing a special token to another offset in the system controller.
+
+The ICST oscillator must be provided inside a system controller node.
+
+Required properties:
+- lock-offset: the offset address into the system controller where the
+ unlocking register is located
+- vco-offset: the offset address into the system controller where the
+ ICST control register is located (even 32 bit address)
+- compatible: must be one of "arm,syscon-icst525" or "arm,syscon-icst307"
+- #clock-cells: must be <0>
+- clocks: parent clock, since the ICST needs a parent clock to derive its
+ frequency from, this attribute is compulsory.
+
+Example:
+
+syscon: syscon@10000000 {
+ compatible = "syscon";
+ reg = <0x10000000 0x1000>;
+
+ oscclk0: osc0@0c {
+ compatible = "arm,syscon-icst307";
+ #clock-cells = <0>;
+ lock-offset = <0x20>;
+ vco-offset = <0x0c>;
+ clocks = <&xtal24mhz>;
+ };
+ (...)
+};