From bdb48e4c7d0796850d4c1a24fe1386677e8a922c Mon Sep 17 00:00:00 2001 From: Darwin Dingel Date: Mon, 10 Dec 2018 11:27:39 +1300 Subject: [PATCH] dt-bindings: serial: 8250: Add rate limit for serial port input overruns When a serial port continuously experiences input overrun from (1) continuous receive characters from remote and or (2) hardware issues, its interrupt handler can preempt other tasks especially when the system is busy (ie. boot up period). This can cause other tasks to get starved of processing time from the CPU. When this dts binding is enabled and input overrun on the serial port is detected, serial port receive will be throttled to give some breathing room for processing other tasks. Value provided will be in milliseconds. &serial0{ overrun-throttle-ms = <500>; }; Signed-off-by: Darwin Dingel Reviewed-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/serial/8250.txt | 1 + 1 file changed, 1 insertion(+) diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt index aeb6db4e..da50321 100644 --- a/Documentation/devicetree/bindings/serial/8250.txt +++ b/Documentation/devicetree/bindings/serial/8250.txt @@ -51,6 +51,7 @@ Optional properties: - tx-threshold: Specify the TX FIFO low water indication for parts with programmable TX FIFO thresholds. - resets : phandle + reset specifier pairs +- overrun-throttle-ms : how long to pause uart rx when input overrun is encountered. Note: * fsl,ns16550: -- 2.7.4