[PATCH 4/8] dt-bindings: devfreq: add DMC device description

From: Lukasz Luba
Date: Mon Jan 28 2019 - 14:22:30 EST


The patch adds description for DT binding for a new Exynos5 Dynamic Memory
Controller device.
It also contains needed MAINTAINERS file updates.

CC: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
CC: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
CC: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
CC: Rob Herring <robh+dt@xxxxxxxxxx>
CC: Mark Rutland <mark.rutland@xxxxxxx>
CC: Kukjin Kim <kgene@xxxxxxxxxx>
CC: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
CC: linux-pm@xxxxxxxxxxxxxxx
CC: linux-samsung-soc@xxxxxxxxxxxxxxx
CC: devicetree@xxxxxxxxxxxxxxx
CC: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Lukasz Luba <l.luba@xxxxxxxxxxxxxxxxxxx>
---
.../devicetree/bindings/devfreq/exynos5-dmc.txt | 108 +++++++++++++++++++++
MAINTAINERS | 7 ++
2 files changed, 115 insertions(+)
create mode 100644 Documentation/devicetree/bindings/devfreq/exynos5-dmc.txt

diff --git a/Documentation/devicetree/bindings/devfreq/exynos5-dmc.txt b/Documentation/devicetree/bindings/devfreq/exynos5-dmc.txt
new file mode 100644
index 0000000..914bd85
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/exynos5-dmc.txt
@@ -0,0 +1,108 @@
+* Exynos5 frequency and voltage scaling for Dynamic Memory Controller device
+
+The Samsung Exynos5 SoC has DMC (Dynamic Memory Controller) to which the DRAM
+memory chips are connected. The driver is to monitor the controller in runtime
+and switch frequency and voltage. To monitor the usage of the controller in
+runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
+is able to measure the current load of the memory.
+When 'userspace' governor is used for the driver, an application is able to
+switch the DMC frequency.
+
+Required properties for DMC device for Exynos5422:
+- compatible: Should be "samsung,exynos5422-bus".
+- clock-names : the name of clock used by the bus, "bus".
+- clocks : phandles for clock specified in "clock-names" property.
+- devfreq-events : phandles for PPMU devices connected to this DMC.
+
+The example definition of a DMC and PPMU devices declared in DT is shown below:
+
+ ppmu_dmc0_0: ppmu_dmc0_0@10d00000 {
+ compatible = "samsung,exynos-ppmu";
+ reg = <0x10d00000 0x2000>;
+ clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
+ clock-names = "ppmu";
+ status = "okay";
+ events {
+ ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
+ event-name = "ppmu-event3-dmc0_0";
+ };
+ };
+ };
+
+
+ ppmu_dmc0_1: ppmu_dmc0_1@10d10000 {
+ compatible = "samsung,exynos-ppmu";
+ reg = <0x10d10000 0x2000>;
+ clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
+ clock-names = "ppmu";
+ status = "okay";
+ events {
+ ppmu_event_dmc0_1: ppmu-event3-dmc0_1 {
+ event-name = "ppmu-event3-dmc0_1";
+ };
+ };
+ };
+
+ ppmu_dmc1_0: ppmu_dmc1_0@10d10000 {
+ compatible = "samsung,exynos-ppmu";
+ reg = <0x10d60000 0x2000>;
+ clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
+ clock-names = "ppmu";
+ status = "okay";
+ events {
+ ppmu_event_dmc1_0: ppmu-event3-dmc1_0 {
+ event-name = "ppmu-event3-dmc1_0";
+ };
+ };
+ };
+
+ ppmu_dmc1_1: ppmu_dmc1_1@10d70000 {
+ compatible = "samsung,exynos-ppmu";
+ reg = <0x10d70000 0x2000>;
+ clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
+ clock-names = "ppmu";
+ status = "okay";
+ events {
+ ppmu_event_dmc1_1: ppmu-event3-dmc1_1 {
+ event-name = "ppmu-event3-dmc1_1";
+ };
+ };
+ };
+
+ dmc: dmc@10c20000 {
+ compatible = "samsung,exynos5422-dmc";
+ reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
+ <0x10030000 0x1000>, <0x10000000 0x1000>;
+ clocks = <&clock CLK_FOUT_SPLL>,
+ <&clock CLK_MOUT_SCLK_SPLL>,
+ <&clock CLK_FF_DOUT_SPLL2>,
+ <&clock CLK_FOUT_BPLL>,
+ <&clock CLK_MOUT_BPLL>,
+ <&clock CLK_SCLK_BPLL>,
+ <&clock CLK_MOUT_MX_MSPLL_CCORE>,
+ <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
+ <&clock CLK_MOUT_MCLK_CDREX>,
+ <&clock CLK_DOUT_CLK2X_PHY0>,
+ <&clock CLK_CLKM_PHY0>,
+ <&clock CLK_CLKM_PHY1>
+ ;
+ clock-names = "fout_spll",
+ "mout_sclk_spll",
+ "ff_dout_spll2",
+ "fout_bpll",
+ "mout_bpll",
+ "sclk_bpll",
+ "mout_mx_mspll_ccore",
+ "mout_mx_mspll_ccore_phy",
+ "mout_mclk_cdrex",
+ "dout_clk2x_phy0",
+ "clkm_phy0",
+ "clkm_phy1"
+ ;
+
+ status = "okay";
+ devfreq-events = <&ppmu_dmc0_0>, <&ppmu_dmc0_1>,
+ <&ppmu_dmc1_0>, <&ppmu_dmc1_1>;
+ };
+
+
diff --git a/MAINTAINERS b/MAINTAINERS
index 9f64f8d..3581807 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3310,6 +3310,13 @@ S: Maintained
F: drivers/devfreq/exynos-bus.c
F: Documentation/devicetree/bindings/devfreq/exynos-bus.txt

+DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5
+M: Lukasz Luba <l.luba@xxxxxxxxxxxxxxxxxxx>
+L: linux-pm@xxxxxxxxxxxxxxx
+L: linux-samsung-soc@xxxxxxxxxxxxxxx
+S: Maintained
+F: Documentation/devicetree/bindings/devfreq/exynos5-dmc.txt
+
BUSLOGIC SCSI DRIVER
M: Khalid Aziz <khalid@xxxxxxxxxxxxxx>
L: linux-scsi@xxxxxxxxxxxxxxx
--
2.7.4