Thread (8 messages) flat view 8 messages, 2 authors, 2016-01-23

[PATCH v2 3/3] mtd: nand: sunxi: add randomizer support

From: Boris Brezillon <hidden>
Date: 2016-01-23 08:18:53
Also in: lkml

Hi Brian,

On Fri, 22 Jan 2016 18:57:13 -0800
Brian Norris [off-list ref] wrote:
All three look good, so pushed to l2-mtd.git/next. One comment below:
Thanks.
On Wed, Dec 02, 2015 at 12:01:07PM +0100, Boris Brezillon wrote:

...
quoted
+static u16 sunxi_nfc_randomizer_state(struct mtd_info *mtd, int page, bool ecc)
+{
+	const u16 *seeds = sunxi_nfc_randomizer_page_seeds;
+	int mod = mtd->erasesize / mtd->writesize;
Richard suggested you use the mtd.h helper here. Patch below.
Yep, I forgot to do this change.
quoted
+
+	if (mod > ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds))
+		mod = ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds);
+
+	if (ecc) {
+		if (mtd->ecc_step_size == 512)
+			seeds = sunxi_nfc_randomizer_ecc512_seeds;
+		else
+			seeds = sunxi_nfc_randomizer_ecc1024_seeds;
+	}
+
+	return seeds[page % mod];
+}
From: Brian Norris <computersforpeace@gmail.com>
Date: Fri, 22 Jan 2016 18:54:02 -0800
Subject: [PATCH] mtd: nand: sunxi: use mtd_div_by_ws() helper

Suggested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Boris Brezillon <redacted>
quoted hunk ↗ jump to hunk
---
 drivers/mtd/nand/sunxi_nand.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 5f700719d5c2..b5ea6b312df0 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -624,7 +624,7 @@ static u16 sunxi_nfc_randomizer_step(u16 state, int count)
 static u16 sunxi_nfc_randomizer_state(struct mtd_info *mtd, int page, bool ecc)
 {
 	const u16 *seeds = sunxi_nfc_randomizer_page_seeds;
-	int mod = mtd->erasesize / mtd->writesize;
+	int mod = mtd_div_by_ws(mtd->erasesize, mtd);
Just a comment (which should not prevent you from applying this patch).
Isn't it a bit overkill to cast the erasesize to a 64 bit value, and
then do a do_div on it. Shouldn't happen often though, because
->writesize_shift should be != 0 in most (all?) cases.

Another related remark: with the MLC/paired pages stuff I'll have to
retrieve this information (number of write units per erase block) quite
often, so maybe we should have a field (and/or an helper) for that.

Thanks,

Boris


-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help