Blackfin Serial Driver: fix missing new lines when under load

Add a SSYNC() into bfin_serial_dma_tx_chars() to ensure DMA registers are
written with new data otherwise we might miss a byte or two when the
system is under load.  PIO mode is OK though.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index dfae22d47bf7..676efdad3712 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -415,6 +415,7 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
         set_dma_x_modify(uart->tx_dma_channel, 1);
+        SSYNC();
         enable_dma(uart->tx_dma_channel);
 
         UART_SET_IER(uart, ETBEI);