[PATCH v2 1/2] dt-bindings: serial: 8250: add Microchip Core16550
From: Kohei Otsuka via B4 Relay
Date: Sun Nov 08 2026 - 21:57:14 EST
From: Kohei Otsuka <kohei@xxxxxxxxxxxxxxxxx>
Core16550 is a 16550-compatible UART soft IP core for Microchip FPGAs,
including the fabric of PolarFire SoC. Its registers, interrupts and
baud rate divisor follow the 16550A, so a driver that knows only
ns16550a operates it fully: transmit, receive, FIFOs and modem control
all work. What the generic driver cannot know is that the core raises
no interrupt on TEMT, which it needs to drop RTS after a frame in
software RS-485 mode (em485). ns16550a therefore stays a valid
fallback, with RS-485 RTS control the one feature that needs the
specific compatible.
Add microchip,core16550-rtl-v3 with ns16550a as the fallback. As for
Microchip's other FPGA fabric cores, the -rtl-v3 suffix is the major
RTL version of the IP, Core16550 3.x.
Link: https://github.com/linux4microchip/meta-mchp/issues/5
Signed-off-by: Kohei Otsuka <kohei@xxxxxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/serial/8250.yaml | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
index 50d5c977afa3..6f806b972f5c 100644
--- a/Documentation/devicetree/bindings/serial/8250.yaml
+++ b/Documentation/devicetree/bindings/serial/8250.yaml
@@ -137,6 +137,7 @@ properties:
- ti,da830-uart
- loongson,ls2k0500-uart
- loongson,ls2k1500-uart
+ - microchip,core16550-rtl-v3
- const: ns16550a
- items:
- enum:
--
2.53.0