On 04.01.22 11:32, Tomasz Moń wrote: > Triggering RX interrupt for every byte defeats the purpose of aging > timer and leads to interrupt starvation at high baud rates. s/starvation/storm/ ? > > Increase receiver trigger level to 8 to increase the minimum period > between RX interrupts to 8 characters time. The tradeoff is increased > latency. In the worst case scenario, where RX data has intercharacter > delay slightly less than aging timer (8 characters time), it can take > up to 63 characters time for the interrupt to be raised since the > reception of the first character. > > Signed-off-by: Tomasz Moń <tomasz.mon@xxxxxxxxxxxxxxx> > --- > drivers/tty/serial/imx.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c > index 90f82e6c54e4..3c812c47ecc0 100644 > --- a/drivers/tty/serial/imx.c > +++ b/drivers/tty/serial/imx.c > @@ -1255,7 +1255,7 @@ static void imx_uart_clear_rx_errors(struct imx_port *sport) > } > > #define TXTL_DEFAULT 2 /* reset default */ > -#define RXTL_DEFAULT 1 /* reset default */ > +#define RXTL_DEFAULT 8 /* 8 characters or aging timer */ > #define TXTL_DMA 8 /* DMA burst setting */ > #define RXTL_DMA 9 /* DMA burst setting */ > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
