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32 lines
1.2 KiB
Text
32 lines
1.2 KiB
Text
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SiFive PWM controller
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Unlike most other PWM controllers, the SiFive PWM controller currently only
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supports one period for all channels in the PWM. All PWMs need to run at
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the same period. The period also has significant restrictions on the values
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it can achieve, which the driver rounds to the nearest achievable period.
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PWM RTL that corresponds to the IP block version numbers can be found
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here:
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https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm
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Required properties:
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- compatible: Should be "sifive,<chip>-pwm" and "sifive,pwm<version>".
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Supported compatible strings are: "sifive,fu540-c000-pwm" for the SiFive
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PWM v0 as integrated onto the SiFive FU540 chip, and "sifive,pwm0" for the
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SiFive PWM v0 IP block with no chip integration tweaks.
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- reg: physical base address and length of the controller's registers
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- clocks: Should contain a clock identifier for the PWM's parent clock.
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- #pwm-cells: Should be 3.
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- interrupts: one interrupt per PWM channel
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Examples:
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pwm: pwm@10020000 {
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compatible = "sifive,fu540-c000-pwm", "sifive,pwm0";
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reg = <0x0 0x10020000 0x0 0x1000>;
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clocks = <&tlclk>;
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interrupt-parent = <&plic>;
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interrupts = <42 43 44 45>;
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#pwm-cells = <3>;
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};
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