From 42e11948ddf68b9f799cad8c0ddeab0a39da33e8 Mon Sep 17 00:00:00 2001 From: Raviteja Narayanam Date: Thu, 9 Apr 2020 11:56:02 +0530 Subject: [PATCH] serial: uartps: Wait for tx_empty in console setup On some platforms, the log is corrupted while console is being registered. It is observed that when set_termios is called, there are still some bytes in the FIFO to be transmitted. So, wait for tx_empty inside cdns_uart_console_setup before calling set_termios. Signed-off-by: Raviteja Narayanam Reviewed-by: Shubhrajyoti Datta Link: https://lore.kernel.org/r/1586413563-29125-2-git-send-email-raviteja.narayanam@xilinx.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/xilinx_uartps.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index 6b26f767768e..0bf946b0b198 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -1260,6 +1260,7 @@ static int cdns_uart_console_setup(struct console *co, char *options) int bits = 8; int parity = 'n'; int flow = 'n'; + unsigned long time_out; if (!port->membase) { pr_debug("console on " CDNS_UART_TTY_NAME "%i not present\n", @@ -1270,6 +1271,13 @@ static int cdns_uart_console_setup(struct console *co, char *options) if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); + /* Wait for tx_empty before setting up the console */ + time_out = jiffies + usecs_to_jiffies(TX_TIMEOUT); + + while (time_before(jiffies, time_out) && + cdns_uart_tx_empty(port) != TIOCSER_TEMT) + cpu_relax(); + return uart_set_options(port, co, baud, parity, bits, flow); } #endif /* CONFIG_SERIAL_XILINX_PS_UART_CONSOLE */