[3.19.y-ckt stable] Patch "mtd: nand: sunxi: fix OOB handling in ->write_xxx() functions" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    mtd: nand: sunxi: fix OOB handling in ->write_xxx() functions

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 29ec235bbcd313f8d69f23deec1b20ea8f86ad4e Mon Sep 17 00:00:00 2001
From: Boris BREZILLON <boris.brezillon at free-electrons.com>
Date: Mon, 14 Sep 2015 10:41:03 +0200
Subject: [PATCH 003/120] mtd: nand: sunxi: fix OOB handling in ->write_xxx()
 functions

commit 03a0e8a7c5ea29b5c4e72dfd64900b47a8fb6f2d upstream.

The USER_DATA register cannot be accessed using byte accessors on A13
SoCs, thus triggering a bug when using memcpy_toio on this register.
Declare an helper macros to convert an OOB buffer into a suitable
USER_DATA value and vice-versa.

This patch also fixes an error in the oob_required logic (some OOB data
are not written even if the user required it) by removing the
oob_required condition, which is perfectly valid since the core already
fill ->oob_poi with FFs when oob_required is false.

Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
Fixes: 1fef62c1423b ("mtd: nand: add sunxi NAND flash controller support")
Signed-off-by: Brian Norris <computersforpeace at gmail.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/mtd/nand/sunxi_nand.c | 26 +++++++++-----------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index ccaa8e2..d753659 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -138,6 +138,10 @@
 #define NFC_ECC_MODE		GENMASK(15, 12)
 #define NFC_RANDOM_SEED		GENMASK(30, 16)

+/* NFC_USER_DATA helper macros */
+#define NFC_BUF_TO_USER_DATA(buf)	((buf)[0] | ((buf)[1] << 8) | \
+					((buf)[2] << 16) | ((buf)[3] << 24))
+
 #define NFC_DEFAULT_TIMEOUT_MS	1000

 #define NFC_SRAM_SIZE		1024
@@ -632,15 +636,9 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
 		offset = layout->eccpos[i * ecc->bytes] - 4 + mtd->writesize;

 		/* Fill OOB data in */
-		if (oob_required) {
-			tmp = 0xffffffff;
-			memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, &tmp,
-				    4);
-		} else {
-			memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE,
-				    chip->oob_poi + offset - mtd->writesize,
-				    4);
-		}
+		writel(NFC_BUF_TO_USER_DATA(chip->oob_poi +
+					    layout->oobfree[i].offset),
+		       nfc->regs + NFC_REG_USER_DATA_BASE);

 		chip->cmdfunc(mtd, NAND_CMD_RNDIN, offset, -1);

@@ -770,14 +768,8 @@ static int sunxi_nfc_hw_syndrome_ecc_write_page(struct mtd_info *mtd,
 		offset += ecc->size;

 		/* Fill OOB data in */
-		if (oob_required) {
-			tmp = 0xffffffff;
-			memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, &tmp,
-				    4);
-		} else {
-			memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob,
-				    4);
-		}
+		writel(NFC_BUF_TO_USER_DATA(oob),
+		       nfc->regs + NFC_REG_USER_DATA_BASE);

 		tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD | NFC_ACCESS_DIR |
 		      (1 << 30);
--
1.9.1