[PATCH v2 13/16] cpufreq: tegra124: Add device tree bindings
Tuomas Tynkkynen
ttynkkynen at nvidia.com
Mon Jul 21 08:38:59 PDT 2014
The cpufreq driver for Tegra124 will be a different one than the old
Tegra20 cpufreq driver (tegra-cpufreq), which does not use the device
tree.
Signed-off-by: Tuomas Tynkkynen <ttynkkynen at nvidia.com>
---
v2 changes:
- The clock-latency property was added, as cpufreq-cpu0 wants that
.../bindings/cpufreq/tegra124-cpufreq.txt | 42 ++++++++++++++++++++++
1 file changed, 42 insertions(+)
create mode 100644 Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt
diff --git a/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt
new file mode 100644
index 0000000..031545a
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt
@@ -0,0 +1,42 @@
+Tegra124 CPU frequency scaling driver bindings
+----------------------------------------------
+
+Both required and optional properties listed below must be defined
+under node /cpus/cpu at 0.
+
+Required properties:
+- clocks: Must contain an entry for each entry in clock-names.
+ See ../clocks/clock-bindings.txt for details.
+- clock-names: Must include the following entries:
+ - cpu_g: Clock mux for the fast CPU cluster.
+ - cpu_lp: Clock mux for the low-power CPU cluster.
+ - pll_x: Fast PLL clocksource.
+ - pll_p: Auxiliary PLL used during fast PLL rate changes.
+ - dfll: Fast DFLL clocksource that also automatically scales CPU voltage.
+
+Optional properties:
+- clock-latency: Specify the possible maximum transition latency for clock,
+ in unit of nanoseconds.
+
+Example:
+--------
+cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu at 0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ reg = <0>;
+
+ clocks = <&tegra_car TEGRA124_CLK_CCLK_G>,
+ <&tegra_car TEGRA124_CLK_CCLK_LP>,
+ <&tegra_car TEGRA124_CLK_PLL_X>,
+ <&tegra_car TEGRA124_CLK_PLL_P>,
+ <&dfll>;
+ clock-names = "cpu_g", "cpu_lp", "pll_x", "pll_p", "dfll";
+ clock-latency = <300000>;
+ };
+
+ <...>
+};
--
1.8.1.5
More information about the linux-arm-kernel
mailing list