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serial: uartps: Wait for tx_empty in console setup

[ Upstream commit 42e11948dd ]

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.narayanam@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5.4-rM2-2.2.x-imx-squashed
Raviteja Narayanam 2020-04-09 11:56:02 +05:30 committed by Greg Kroah-Hartman
parent ab1d9bad60
commit 26d261f32f
1 changed files with 8 additions and 0 deletions

View File

@ -1248,6 +1248,7 @@ 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",
@ -1258,6 +1259,13 @@ 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);
}