ARC: [dts] Introduce Timer bindings

ARC Timers have historically been probed directly.
As precursor to start probing Timers thru DT introduce these bindings
Note that to keep series bisectable, these bindings are not yet used in
code.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: devicetree@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/timer/snps,arc-timer.txt b/Documentation/devicetree/bindings/timer/snps,arc-timer.txt
new file mode 100644
index 000000000000..4ef024630d61
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/snps,arc-timer.txt
@@ -0,0 +1,31 @@
+Synopsys ARC Local Timer with Interrupt Capabilities
+- Found on all ARC CPUs (ARC700/ARCHS)
+- Can be optionally programmed to interrupt on Limit
+- Two idential copies TIMER0 and TIMER1 exist in ARC cores and historically
+  TIMER0 used as clockevent provider (true for all ARC cores)
+  TIMER1 used for clocksource (mandatory for ARC700, optional for ARC HS)
+
+Required properties:
+
+- compatible : should be "snps,arc-timer"
+- interrupts : single Interrupt going into parent intc
+	       (16 for ARCHS cores, 3 for ARC700 cores)
+- clocks     : phandle to the source clock
+
+Optional properties:
+
+- interrupt-parent : phandle to parent intc
+
+Example:
+
+	timer0 {
+		compatible = "snps,arc-timer";
+		interrupts = <3>;
+		interrupt-parent = <&core_intc>;
+		clocks = <&core_clk>;
+	};
+
+	timer1 {
+		compatible = "snps,arc-timer";
+		clocks = <&core_clk>;
+	};