commit eca84e99d1afac871cd85b3444862f36fa8bbb37
author Andy Shevchenko <andriy.shevchenko@linux.intel.com> Mon Oct 10 11:27:19 2016 +0300
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Thu Oct 27 16:27:24 2016 +0200
tree 604a5e22d2d33f5a7a8fc3d4de1c6dff1ee9bfb5
parent 3f3a46951e02a89961f47db97624767b5b9befec

serial: 8250_lpss: Try to enable Memory-Write-Invalidate

Enable MWI mechanism if PCI bus master supports it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_lpss.c

diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c
index 353c90e..ac2a34e 100644
--- a/drivers/tty/serial/8250/8250_lpss.c
+++ b/drivers/tty/serial/8250/8250_lpss.c
@@ -184,6 +184,7 @@
 		return;
 
 	pci_set_master(pdev);
+	pci_try_set_mwi(pdev);
 
 	/* Special DMA address for UART */
 	dma->rx_dma_addr = 0xfffff000;