[RFC PATCH 2/7] dt-bindings: soc: Add opp table on scpsys bindings

Henry Chen
2019-01-02T14:02:35Z

Add opp table on scpsys dt-bindings for Mediatek SoC.

Signed-off-by: Henry Chen <henryc.chen@mediatek.com>
---
Documentation/devicetree/bindings/opp/mtk-opp.txt | 24 +++++++++++++
.../devicetree/bindings/soc/mediatek/scpsys.txt | 42 ++++++++++++++++++++++
2 files changed, 66 insertions(+)
create mode 100644 Documentation/devicetree/bindings/opp/mtk-opp.txt

diff --git a/Documentation/devicetree/bindings/opp/mtk-opp.txt b/Documentation/devicetree/bindings/opp/mtk-opp.txt
new file mode 100644
index 0000000..036be1c
--- /dev/null
+++ b/Documentation/devicetree/bindings/opp/mtk-opp.txt
@@ -0,0 +1,24 @@
+Mediatek OPP bindings to descibe OPP nodes with level values
+
+OPP tables for devices on Mediatek platforms require an additional
+platform specific level value to be specified.
+This value is passed on to the mediatek Power Management Unit by the
+CPU, which then takes the necessary actions to set a voltage rail
+to an appropriate voltage based on the value passed.
+
+The bindings are based on top of the operating-points-v2 bindings
+described in Documentation/devicetree/bindings/opp/opp.txt
+Additional properties are described below.
+
+* OPP Table Node
+
+Required properties:
+- compatible: Allow OPPs to express their compatibility. It should be:
+ "operating-points-v2-mtk-level"
+
+* OPP Node
+
+Required properties:
+- mtk,level: On Mediatek platforms an OPP node can describe a positive value
+representing a level that's communicated with a our power management hardware
+which then translates it into a certain voltage on a voltage rail.
diff --git a/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt b/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt
index b4728ce..299b526 100644
--- a/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt
+++ b/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt
@@ -63,6 +63,10 @@ Optional properties:
- mfg_2d-supply: Power supply for the mfg_2d power domain
- mfg-supply: Power supply for the mfg power domain

+- operating-points-v2: Phandle to the OPP table for the Power domain.
+ Refer to Documentation/devicetree/bindings/power/power_domain.txt
+ and Documentation/devicetree/bindings/opp/mtk-opp.txt for more details
+
Example:

scpsys: scpsys@10006000 {
@@ -75,6 +79,27 @@ Example:
<&topckgen CLK_TOP_VENC_SEL>,
<&topckgen CLK_TOP_VENC_LT_SEL>;
clock-names = "mfg", "mm", "venc", "venc_lt";
+ operating-points-v2 = <&dvfsrc_opp_table>;
+
+ dvfsrc_opp_table: opp-table {
+ compatible = "operating-points-v2-mtk-level";
+
+ dvfsrc_vol_min: opp1 {
+ mtk,level = <MT8183_DVFSRC_LEVEL_1>;
+ };
+
+ dvfsrc_freq_medium: opp2 {
+ mtk,level = <MT8183_DVFSRC_LEVEL_2>;
+ };
+
+ dvfsrc_freq_max: opp3 {
+ mtk,level = <MT8183_DVFSRC_LEVEL_3>;
+ };
+
+ dvfsrc_vol_max: opp4 {
+ mtk,level = <MT8183_DVFSRC_LEVEL_4>;
+ };
+ };
};

Example consumer:
@@ -82,4 +107,21 @@ Example consumer:
afe: mt8173-afe-pcm@11220000 {
compatible = "mediatek,mt8173-afe-pcm";
power-domains = <&scpsys MT8173_POWER_DOMAIN_AUDIO>;
+ operating-points-v2 = <&aud_opp_table>;
+ };
+
+ aud_opp_table: aud-opp-table {
+ compatible = "operating-points-v2";
+ opp1 {
+ opp-hz = /bits/ 64 <793000000>;
+ required-opps = <&dvfsrc_vol_min>;
+ };
+ opp2 {
+ opp-hz = /bits/ 64 <910000000>;
+ required-opps = <&dvfsrc_vol_max>;
+ };
+ opp3 {
+ opp-hz = /bits/ 64 <1014000000>;
+ required-opps = <&dvfsrc_vol_max>;
+ };
};