On Fri, 18 Sep 2020 at 07:51, Sasha Levin sashal@kernel.org wrote:
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
stable rc branch 4.4 arm64 build broken.
../drivers/tty/serial/xilinx_uartps.c: In function ‘cdns_uart_console_setup’: ../drivers/tty/serial/xilinx_uartps.c:1170:40: error: ‘TX_TIMEOUT’ undeclared (first use in this function) 1170 | time_out = jiffies + usecs_to_jiffies(TX_TIMEOUT); ^~~~~~~~~~ Reported-by: Naresh Kamboju naresh.kamboju@linaro.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 06efcef1b4953..5b4469098888a 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -1152,6 +1152,7 @@ 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;
@@ -1165,6 +1166,13 @@ 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);
}
-- 2.25.1