[PATCH v3 1/2] dt-bindings: serial: add documentation for the SiFive UART driver

[Paul Walmsley]

Add DT binding documentation for the Linux driver for the SiFive
asynchronous serial IP block.

Cc: linux-serial@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxx>
Reviewed-by: Palmer Dabbelt <palmer@xxxxxxxxxx>
Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Signed-off-by: Paul Walmsley <paul@xxxxxxxxx>
---
v3: update description and example for compatible strings, per
    discussion with Rob Herring.

 .../bindings/serial/sifive-serial.txt         | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/serial/sifive-serial.txt

diff --git a/Documentation/devicetree/bindings/serial/sifive-serial.txt b/Documentation/devicetree/bindings/serial/sifive-serial.txt
new file mode 100644
index 000000000000..a426b18ba049
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/sifive-serial.txt
@@ -0,0 +1,33 @@
+SiFive asynchronous serial interface (UART)
+
+Required properties:
+
+- compatible: should be something similar to
+	      "sifive,<chip>-uart<version>" for the UART as integrated
+	      on a particular chip, and "sifive,uart<version>" for the
+	      general UART IP block programming model.	Supported
+	      compatible strings as of the date of this writing are:
+	      "sifive,fu540-c000-uart0" for the SiFive UART v0 as
+	      integrated onto the SiFive FU540 chip, or "sifive,uart0"
+	      for the SiFive UART v0 IP block with no chip integration
+	      tweaks (if any)
+- reg: address and length of the register space
+- interrupts: Should contain the UART interrupt identifier
+- clocks: Should contain a clock identifier for the UART's parent clock
+
+
+UART RTL that corresponds to the IP block version numbers can be found
+here:
+
+https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart
+
+
+Example:
+
+uart0: serial@10010000 {
+	compatible = "sifive,fu540-c000-uart0", "sifive,uart0";
+	interrupt-parent = <&plic0>;
+	interrupts = <80>;
+	reg = <0x0 0x10010000 0x0 0x1000>;
+	clocks = <&prci PRCI_CLK_TLCLK>;
+};
-- 
2.19.1