Re: [PATCH 1/3 v2] MTD: atmel_nand: modify test case for using DMA operations

Re: [PATCH 1/3 v2] MTD: atmel_nand: modify test case for using DMA operations

[Artem Bityutskiy]

On Fri, 2011-04-01 at 16:40 +0200, Nicolas Ferre wrote:
> We have better performances not using DMA for oob operations.
> Modify size test so that it is using DMA for size greater than oobsize.
> 
> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Pushed to l2-mtd-2.6.git, thank you!

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)

[PATCH 1/3 v2] MTD: atmel_nand: modify test case for using DMA operations

[Nicolas Ferre]

We have better performances not using DMA for oob operations.
Modify size test so that it is using DMA for size greater than oobsize.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
Artem,

Here is the v2 version with embedded comment as you suggested.

Best regards,

 drivers/mtd/nand/atmel_nand.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 6fae04b..5872f2a 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -280,7 +280,8 @@ static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
 	struct nand_chip *chip = mtd->priv;
 	struct atmel_nand_host *host = chip->priv;
 
-	if (use_dma && len >= mtd->oobsize)
+	if (use_dma && len > mtd->oobsize)
+		/* only use DMA for bigger than oob size: better performances */
 		if (atmel_nand_dma_op(mtd, buf, len, 1) == 0)
 			return;
 
@@ -295,7 +296,8 @@ static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
 	struct nand_chip *chip = mtd->priv;
 	struct atmel_nand_host *host = chip->priv;
 
-	if (use_dma && len >= mtd->oobsize)
+	if (use_dma && len > mtd->oobsize)
+		/* only use DMA for bigger than oob size: better performances */
 		if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0)
 			return;
 
-- 
1.7.3