From: Anson Huang <Anson.Huang@xxxxxxx>
Systems which use platform driver model for clock driver require the
clock frequency to be supplied via device tree when system counter
driver is enabled.
This is necessary as in the platform driver model the of_clk operations
do not work correctly because system counter driver is initialized in
early phase of system boot up, and clock driver using platform driver
model is NOT ready at that time, it will cause system counter driver
initialization failed.
Add the optinal clock-frequency to the device tree bindings of the NXP
system counter, so the frequency can be handed in and the of_clk
operations can be skipped.
Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
Changes since V1:
- improve commit log, no content change.
---
Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt b/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt
index d576599..c9907a0 100644
--- a/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt
+++ b/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt
@@ -14,6 +14,11 @@ Required properties:
- clocks : Specifies the counter clock.
- clock-names: Specifies the clock's name of this module
+Optional properties:
+
+- clock-frequency : Specifies system counter clock frequency and indicates system
+ counter driver to skip clock operations.
+
Example:
system_counter: timer@306a0000 {
@@ -22,4 +27,5 @@ Example:
clocks = <&clk_8m>;
clock-names = "per";
interrupts = <GIC_SPI 47 IRQ_TYPE_LEVEL_HIGH>;
+ clock-frequency = <8333333>;
};
--
2.7.4
