From 7c0105901778500f6d11ddfd99f6efa1987c37a6 Mon Sep 17 00:00:00 2001 From: Sherry Sun Date: Mon, 30 Jan 2023 14:44:45 +0800 Subject: [PATCH] tty: serial: fsl_lpuart: set receive watermark for imx8qxp platform Since imx8qxp RX FIFO depth is 64 datawords, it will be better to set the rx watermark as 31, which means when the number of datawords in the receive FIFO(>= 32) is greater than the watermark, an interrupt or a DMA request is generated. Also keep the console rx watermark as 1 to make sure it responsive. Signed-off-by: Sherry Sun Link: https://lore.kernel.org/r/20230130064449.9564-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/fsl_lpuart.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index e4aa161e61bfb..868c2783d2c74 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -321,7 +321,7 @@ static struct lpuart_soc_data imx8qxp_data = { .devtype = IMX8QXP_LPUART, .iotype = UPIO_MEM32, .reg_off = IMX_REG_OFF, - .rx_watermark = 1, + .rx_watermark = 31, }; static struct lpuart_soc_data imxrt1050_data = { .devtype = IMXRT1050_LPUART, @@ -1527,6 +1527,8 @@ static void lpuart_setup_watermark(struct lpuart_port *sport) writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO); } + if (uart_console(&sport->port)) + sport->rx_watermark = 1; writeb(0, sport->port.membase + UARTTWFIFO); writeb(sport->rx_watermark, sport->port.membase + UARTRWFIFO); @@ -1563,6 +1565,8 @@ static void lpuart32_setup_watermark(struct lpuart_port *sport) lpuart32_write(&sport->port, val, UARTFIFO); /* set the watermark */ + if (uart_console(&sport->port)) + sport->rx_watermark = 1; val = (sport->rx_watermark << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF); lpuart32_write(&sport->port, val, UARTWATER); -- 2.30.2