Adding clk scaling dt parameters.
Signed-off-by: Ram Prakash Gupta <rampraka@xxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/mmc/sdhci-msm.txt | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
index da4edb1..afaf88d 100644
--- a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
+++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
@@ -39,6 +39,21 @@ Required properties:
"cal" - reference clock for RCLK delay calibration (optional)
"sleep" - sleep clock for RCLK delay calibration (optional)
+Optional properties:
+- devfreq,freq-table - specifies supported frequencies for clock scaling.
+ Clock scaling logic shall toggle between these frequencies based
+ on card load. In case the defined frequencies are over or below
+ the supported card frequencies, they will be overridden
+ during card init. In case this entry is not supplied,
+ the driver will construct one based on the card
+ supported max and min frequencies.
+ The frequencies must be ordered from lowest to highest.
+
+- scaling-lower-bus-speed-mode - Few hosts can support DDR52 mode at the
+ same lower system voltage corner as high-speed mode. In such
+ cases, it is always better to put it in DDR mode which will
+ improve the performance without any power impact.
+
Example:
sdhc_1: sdhci@f9824900 {
@@ -56,6 +71,10 @@ Example:
clocks = <&gcc GCC_SDCC1_APPS_CLK>, <&gcc GCC_SDCC1_AHB_CLK>;
clock-names = "core", "iface";
+
+ devfreq,freq-table = <50000000 200000000>;
+ scaling-lower-bus-speed-mode = "DDR52"
+
};
sdhc_2: sdhci@f98a4900 {
--
1.9.1
