[PATCH v10 1/7] clk: hi3xxx: add clock support
From: Mike Turquette <hidden>
Date: 2013-10-30 19:44:00
Also in:
linux-devicetree
Quoting Haojian Zhuang (2013-10-15 02:16:11)
Add clock support with device tree on Hisilicon SoC. Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org> Cc: Mike Turquette <redacted>
Hello Haojian, This patch looks mostly good to me but I have a few comments on the binding below.
quoted hunk
--- .../devicetree/bindings/clock/hisilicon.txt | 99 +++++++++ drivers/clk/Makefile | 1 + drivers/clk/hisilicon/Makefile | 2 + drivers/clk/hisilicon/clk-hi3xxx.c | 221 +++++++++++++++++++++ drivers/clk/hisilicon/clk-hi3xxx.h | 34 ++++ drivers/clk/hisilicon/clkgate-seperated.c | 129 ++++++++++++ 6 files changed, 486 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/hisilicon.txt create mode 100644 drivers/clk/hisilicon/Makefile create mode 100644 drivers/clk/hisilicon/clk-hi3xxx.c create mode 100644 drivers/clk/hisilicon/clk-hi3xxx.h create mode 100644 drivers/clk/hisilicon/clkgate-seperated.cdiff --git a/Documentation/devicetree/bindings/clock/hisilicon.txt b/Documentation/devicetree/bindings/clock/hisilicon.txt new file mode 100644 index 0000000..c29b9ef --- /dev/null +++ b/Documentation/devicetree/bindings/clock/hisilicon.txt@@ -0,0 +1,99 @@ +Device Tree Clock bindings for arch-hi3xxx + +This binding uses the common clock binding[1]. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties for mux clocks: + - compatible : shall be "hisilicon,clk-mux". + - clocks : shall be the input parent clock phandle for the clock. This should + be the reference clock. + - clock-output-names : shall be reference name. + - #clock-cells : from common clock binding; shall be set to 0. + - reg : the mux register address. It should be the offset of the container. + - clkmux-mask : mask bits of the mux register. + - clkmux-table : array of mux select bits. + +Optional properties for mux clocks: + - clkmux-hiword-mask : indicates that the bit[31:16] are the hiword mask + of mux selected bits (bit[15:0]). The bit[15:0] is valid only when + bit[31:16] is set.
The masks are enumerated in clkmux-table. Can these masks include the hiword-mask bits as well? This will mean that you can eliminate the clkmux-hiword-mask property entirely. As an example: reg = <0xfc802000 0x4>; clkmux-table = <0x80000000 0x80008000>;
+
+
+
+Required properties for gate clocks:
+ - compatible : shall be "hisilicon,clk-gate".
+ - clocks : shall be the input parent clock phandle for the clock. This should
+ be the reference clock.
+ - clock-output-names : shall be reference name.
+ - #clock-cells : from common clock binding; shall be set to 0.
+ - reg : the mux register address. It should be the offset of the container.
+ - clkgate : bit index to control the clock gate in the gate register.
+
+Optional properties for gate clocks:
+ - clkgate-inverted : it indicates that setting 0 could enable the clock gate
+ and setting 1 could disable the clock gate.
+ - clkgate-seperated-reg : it indicates that there're three continuous
+ registers (enable, disable & status) for the same clock gate.
+
+
+
+Required properties for divider clocks:
+ - compatible : shall be "hisilicon,clk-div".
+ - clocks : shall be the input parent clock phandle for the clock. This should
+ be the reference clock.
+ - clock-output-names : shall be reference name.
+ - reg : the divider register address. It should be the offset of the
+ container.
+ - clkdiv-mask : mask bits of the divider register.
+ - clkdiv-min : the minimum divider of the clock divider.
+ - clkdiv-max : the maximum divider of the clock divider.
+
+Optional properties for divider clocks:
+ - clkdiv-hiword-mask : indicates that the bit[31:16] are the hiword mask
+ of divider selected bits (bit[15:0]). The bit[15:0] is valid only when
+ bit[31:16] is set.
+
+
+
+For example:
+ timer0_mux: timer0_mux at fc802000 {
+ compatible = "hisilicon,clk-mux";
+ #clock-cells = <0>;
+ clocks = <&osc32k &timerclk01>;
+ clock-output-names = "timer0_mux";
+ reg = <0xfc802000 0x4>;
+ clkmux-mask = <0x8000>;
+ clkmux-table = <0 0x8000>;Can you eliminate the clkmux-mask property as well? Since you enumerate the clkmux-table property you should be able to derive the mask from the entries in that table. Regards, Mike