The interpretation of opp-supported-hw bits for imx-cpufreq-dt driver is
not very obvious so attempt to explain it.
There is no OF compat string associated.
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
---
.../bindings/cpufreq/imx-cpufreq-dt.txt | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 Documentation/devicetree/bindings/cpufreq/imx-cpufreq-dt.txt
diff --git a/Documentation/devicetree/bindings/cpufreq/imx-cpufreq-dt.txt b/Documentation/devicetree/bindings/cpufreq/imx-cpufreq-dt.txt
new file mode 100644
index 000000000000..87bff5add3f9
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/imx-cpufreq-dt.txt
@@ -0,0 +1,37 @@
+i.MX CPUFreq-DT OPP bindings
+================================
+
+Certain i.MX SoCs support different OPPs depending on the "market segment" and
+"speed grading" value which are written in fuses. These bits are combined with
+the opp-supported-hw values for each OPP to check if the OPP is allowed.
+
+Required properties:
+--------------------
+
+For each opp entry in 'operating-points-v2' table:
+- opp-supported-hw: Two bitmaps indicating:
+ - Supported speed grade mask
+ - Supported market segment mask
+ 0: Consumer
+ 1: Extended Consumer
+ 2: Industrial
+ 3: Automotive
+
+Example:
+--------
+
+opp_table {
+ compatible = "operating-points-v2";
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ /* grade >= 0, consumer only */
+ opp-supported-hw = <0xf>, <0x3>;
+ };
+
+ opp-1300000000 {
+ opp-hz = /bits/ 64 <1300000000>;
+ opp-microvolt = <1000000>;
+ /* grade >= 1, all segments */
+ opp-supported-hw = <0xe>, <0x7>;
+ };
+}
--
2.17.1
