Subject: [PATCH 1/5] serial: pl011: Allocate TX DMA buffer from DMA capable memory

From: [email-masked] (Andrew Jackson)
Date: Fri, 07 Nov 2014 14:14:35 +0000

Allocating with __GFP_DMA avoids the need for bounce buffers

Signed-off-by: Andrew Jackson <[email-masked]>
---
 drivers/tty/serial/amba-pl011.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 8572f2a..a285196 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -987,7 +987,7 @@ 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;
-- 
1.7.1