From: Michal Suchanek <hramrach@gmail.com>
Date: Thu, 23 Jul 2015 16:04:49 +0000 (+0200)
Subject: dmaengine: pl330: do not emit loop for 1 byte transfer.
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=31495d60a06524f37a9ea66d7d62ce0418ef3506;p=deliverable%2Flinux.git

dmaengine: pl330: do not emit loop for 1 byte transfer.

When there is only one burst required do not emit loop instructions to
loop exactly once. Emit just the body of the loop.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
---

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index f513f77b1d85..257e0d90475a 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1198,6 +1198,9 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	unsigned lcnt0, lcnt1, ljmp0, ljmp1;
 	struct _arg_LPEND lpend;
 
+	if (*bursts == 1)
+		return _bursts(dry_run, buf, pxs, 1);
+
 	/* Max iterations possible in DMALP is 256 */
 	if (*bursts >= 256*256) {
 		lcnt1 = 256;