Configure DMA to use 16B burst size with Elkhart Lake. This makes the bus use more efficient and works around an issue which occurs with the previously used 1B.
The fix was initially developed by Srikanth Thokala and Aman Kumar. This together with the previous config change is the cleaned up version of the original fix.
Fixes: 0a9410b981e9 ("serial: 8250_lpss: Enable DMA on Intel Elkhart Lake") Cc: stable@vger.kernel.org # serial: 8250_lpss: Configure DMA also w/o DMA filter Reported-by: Wentong Wu wentong.wu@intel.com Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com --- drivers/tty/serial/8250/8250_lpss.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c index 7d9cddbfef40..0e43bdfb7459 100644 --- a/drivers/tty/serial/8250/8250_lpss.c +++ b/drivers/tty/serial/8250/8250_lpss.c @@ -174,6 +174,8 @@ static int ehl_serial_setup(struct lpss8250 *lpss, struct uart_port *port) */ up->dma = dma;
+ lpss->dma_maxburst = 16; + port->set_termios = dw8250_do_set_termios;
return 0;