From: Raviteja Narayanam raviteja.narayanam@xilinx.com
[ Upstream commit 42e11948ddf68b9f799cad8c0ddeab0a39da33e8 ]
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 raviteja.narayanam@xilinx.com Reviewed-by: Shubhrajyoti Datta shubhrajyoti.datta@xilinx.com Link: https://lore.kernel.org/r/1586413563-29125-2-git-send-email-raviteja.narayan... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 81657f09761cd..00a740b8ad273 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -1282,6 +1282,7 @@ 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 (co->index < 0 || co->index >= CDNS_UART_NR_PORTS) return -EINVAL; @@ -1295,6 +1296,13 @@ 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); }