64 lines
1.5 KiB
Plaintext
64 lines
1.5 KiB
Plaintext
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NVIDIA Tegra20 Clock And Reset Controller
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This binding uses the common clock binding:
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Documentation/devicetree/bindings/clock/clock-bindings.txt
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The CAR (Clock And Reset) Controller on Tegra is the HW module responsible
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for muxing and gating Tegra's clocks, and setting their rates.
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Required properties :
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- compatible : Should be "nvidia,tegra20-car"
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- reg : Should contain CAR registers location and length
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- clocks : Should contain phandle and clock specifiers for two clocks:
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the 32 KHz "32k_in", and the board-specific oscillator "osc".
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- #clock-cells : Should be 1.
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In clock consumers, this cell represents the clock ID exposed by the
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CAR. The assignments may be found in header file
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<dt-bindings/clock/tegra20-car.h>.
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- #reset-cells : Should be 1.
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In clock consumers, this cell represents the bit number in the CAR's
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array of CLK_RST_CONTROLLER_RST_DEVICES_* registers.
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Example SoC include file:
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/ {
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tegra_car: clock {
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compatible = "nvidia,tegra20-car";
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reg = <0x60006000 0x1000>;
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#clock-cells = <1>;
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#reset-cells = <1>;
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};
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usb@c5004000 {
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clocks = <&tegra_car TEGRA20_CLK_USB2>;
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};
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};
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Example board file:
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/ {
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clocks {
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compatible = "simple-bus";
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#address-cells = <1>;
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#size-cells = <0>;
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osc: clock@0 {
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compatible = "fixed-clock";
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reg = <0>;
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#clock-cells = <0>;
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clock-frequency = <12000000>;
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};
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clk_32k: clock@1 {
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compatible = "fixed-clock";
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reg = <1>;
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#clock-cells = <0>;
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clock-frequency = <32768>;
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};
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};
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&tegra_car {
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clocks = <&clk_32k> <&osc>;
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};
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};
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