39 lines
1.5 KiB
Plaintext
39 lines
1.5 KiB
Plaintext
Amlogic Meson SoC UART Serial Interface
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=======================================
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The Amlogic Meson SoC UART Serial Interface is present on a large range
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of SoCs, and can be present either in the "Always-On" power domain or the
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"Everything-Else" power domain.
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The particularity of the "Always-On" Serial Interface is that the hardware
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is active since power-on and does not need any clock gating and is usable
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as very early serial console.
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Required properties:
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- compatible : compatible: value should be different for each SoC family as :
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- Meson6 : "amlogic,meson6-uart"
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- Meson8 : "amlogic,meson8-uart"
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- Meson8b : "amlogic,meson8b-uart"
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- GX (GXBB, GXL, GXM) : "amlogic,meson-gx-uart"
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eventually followed by : "amlogic,meson-ao-uart" if this UART interface
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is in the "Always-On" power domain.
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- reg : offset and length of the register set for the device.
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- interrupts : identifier to the device interrupt
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- clocks : a list of phandle + clock-specifier pairs, one for each
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entry in clock names.
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- clock-names :
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* "xtal" for external xtal clock identifier
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* "pclk" for the bus core clock, either the clk81 clock or the gate clock
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* "baud" for the source of the baudrate generator, can be either the xtal
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or the pclk.
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e.g.
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uart_A: serial@84c0 {
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compatible = "amlogic,meson-gx-uart";
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reg = <0x0 0x84c0 0x0 0x14>;
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interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>;
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/* Use xtal as baud rate clock source */
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clocks = <&xtal>, <&clkc CLKID_UART0>, <&xtal>;
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clock-names = "xtal", "pclk", "baud";
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};
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