[PATCH 1/2] mtd: nand: sunxi: Actually use DMA for subpage reads

[PATCH 1/2] mtd: nand: sunxi: Actually use DMA for subpage reads

[Boris Brezillon]

ecc->read_subpage is set to sunxi_nfc_hw_ecc_read_subpage_dma when
->dmac != NULL, but is then unconditionally overwritten in the common
init path.

Remove this extra assignment to allow usage of the DMA operation when
possible.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
 drivers/mtd/nand/sunxi_nand.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 118a26fff368..a4e43026c35d 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -1922,7 +1922,6 @@ static int sunxi_nand_hw_ecc_ctrl_init(struct mtd_info *mtd,
 	ecc->write_subpage = sunxi_nfc_hw_ecc_write_subpage;
 	ecc->read_oob_raw = nand_read_oob_std;
 	ecc->write_oob_raw = nand_write_oob_std;
-	ecc->read_subpage = sunxi_nfc_hw_ecc_read_subpage;
 
 	return 0;
 }
-- 
2.7.4

[PATCH 2/2] mtd: nand: sunxi: Remove unneeded ->cmdfunc(NAND_CMD_READ0, 0, page)

[Boris Brezillon]

The core already sends the NAND_CMD_READ0 for us. Duplicating this call
in the driver is useless and introduces a perf penalty.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
 drivers/mtd/nand/sunxi_nand.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index a4e43026c35d..84bcee5b0fa0 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -1301,7 +1301,6 @@ static int sunxi_nfc_hw_ecc_read_subpage(struct mtd_info *mtd,
 
 	sunxi_nfc_hw_ecc_enable(mtd);
 
-	chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
 	for (i = data_offs / ecc->size;
 	     i < DIV_ROUND_UP(data_offs + readlen, ecc->size); i++) {
 		int data_off = i * ecc->size;
-- 
2.7.4

Re: [PATCH 1/2] mtd: nand: sunxi: Actually use DMA for subpage reads

[Boris Brezillon]

On Tue, 16 May 2017 00:23:45 +0200
Boris Brezillon <boris.brezillon@free-electrons.com> wrote:

> ecc->read_subpage is set to sunxi_nfc_hw_ecc_read_subpage_dma when
> ->dmac != NULL, but is then unconditionally overwritten in the common  
> init path.
> 
> Remove this extra assignment to allow usage of the DMA operation when
> possible.
> 

Applied both to nand/next.

> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
>  drivers/mtd/nand/sunxi_nand.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
> index 118a26fff368..a4e43026c35d 100644
> --- a/drivers/mtd/nand/sunxi_nand.c
> +++ b/drivers/mtd/nand/sunxi_nand.c
> @@ -1922,7 +1922,6 @@ static int sunxi_nand_hw_ecc_ctrl_init(struct mtd_info *mtd,
>  	ecc->write_subpage = sunxi_nfc_hw_ecc_write_subpage;
>  	ecc->read_oob_raw = nand_read_oob_std;
>  	ecc->write_oob_raw = nand_write_oob_std;
> -	ecc->read_subpage = sunxi_nfc_hw_ecc_read_subpage;
>  
>  	return 0;
>  }