serial: pl011: Allocate TX DMA buffer from DMA capable memory

Allocating with __GFP_DMA avoids the need for bounce buffers

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 83c8f72..8654049 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -988,7 +988,7 @@ static void pl011_dma_startup(struct uart_amba_port *uap)
        if (!uap->dmatx.chan)
                return;
 
-       uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL);
+       uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL | __GFP_DMA);
        if (!uap->dmatx.buf) {
                dev_err(uap->port.dev, "no memory for DMA TX buffer\n");
                uap->port.fifosize = uap->fifosize;