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Otherwise the console will very likely end up being non-functional, as further values are derived from the baudrate (like the transmit timeout), and using -1 will result in screwed parameters being derived from the baudrate. Signed-off-by: Roger Pau Monn=C3=A9 --- xen/drivers/char/ns16550.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c index b23e85a3c68b..130e292f057d 100644 --- a/xen/drivers/char/ns16550.c +++ b/xen/drivers/char/ns16550.c @@ -346,9 +346,16 @@ static void ns16550_setup_preirq(struct ns16550 *uart) if ( divisor ) uart->baud =3D uart->clock_hz / (divisor << 4); else + { + uart->baud =3D 115200; printk(XENLOG_ERR "Automatic baud rate determination was requested," - " but a baud rate was not set up\n"); + " but a baud rate was not set up\n" + "Setting baudrate to %u\n", uart->baud); + divisor =3D uart->clock_hz / (uart->baud << 4); + ns_write_reg(uart, UART_DLL, (uint8_t)divisor); + ns_write_reg(uart, UART_DLM, (uint8_t)(divisor >> 8)); + } } ns_write_reg(uart, UART_LCR, lcr); =20 --=20 2.51.0