diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250_early.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c index 362c25ff188a..ae6a256524d8 100644 --- a/drivers/tty/serial/8250/8250_early.c +++ b/drivers/tty/serial/8250/8250_early.c @@ -122,12 +122,14 @@ static void __init init_port(struct earlycon_device *device) serial8250_early_out(port, UART_FCR, 0); /* no fifo */ serial8250_early_out(port, UART_MCR, 0x3); /* DTR + RTS */ - divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * device->baud); - c = serial8250_early_in(port, UART_LCR); - serial8250_early_out(port, UART_LCR, c | UART_LCR_DLAB); - serial8250_early_out(port, UART_DLL, divisor & 0xff); - serial8250_early_out(port, UART_DLM, (divisor >> 8) & 0xff); - serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB); + if (port->uartclk && device->baud) { + divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * device->baud); + c = serial8250_early_in(port, UART_LCR); + serial8250_early_out(port, UART_LCR, c | UART_LCR_DLAB); + serial8250_early_out(port, UART_DLL, divisor & 0xff); + serial8250_early_out(port, UART_DLM, (divisor >> 8) & 0xff); + serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB); + } } int __init early_serial8250_setup(struct earlycon_device *device, |