[PATCH 1/3] mtd: rawnand: marvell: Ensure program page operations are successful

[Miquel Raynal]

The NAND core complies with the ONFI specification, which itself
mentions that after any program or erase operation, a status check
should be performed to see whether the operation was finished *and*
successful.

The NAND core offers helpers to finish a page write (sending the
"PAGE PROG" command, waiting for the NAND chip to be ready again, and
checking the operation status). But in some cases, advanced controller
drivers might want to optimize this and craft their own page write
helper to leverage additional hardware capabilities, thus not always
using the core facilities.

Some drivers, like this one, do not use the core helper to finish a page
write because the final cycles are automatically managed by the
hardware. In this case, the additional care must be taken to manually
perform the final status check.

Let's read the NAND chip status at the end of the page write helper and
return -EIO upon error.

Cc: stable at vger.kernel.org
Fixes: 02f26ecf8c77 ("mtd: nand: add reworked Marvell NAND controller driver")
Reported-by: Aviram Dali <aviramd at marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>

---

Hello Aviram,

I have not tested this, but based on your report I believe the status
check is indeed missing here and could sometimes lead to unnoticed
partial writes.

Please test on your side and reply with your Tested-by if you validate
the change.

Any backport on kernels predating v4.17 will likely fail because of a
folder rename, so you will have to do the backport manually if needed.

Thanks,
Miquèl
---
 drivers/mtd/nand/raw/marvell_nand.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c
index 30c15e4e1cc0..576441095012 100644
--- a/drivers/mtd/nand/raw/marvell_nand.c
+++ b/drivers/mtd/nand/raw/marvell_nand.c
@@ -1162,6 +1162,7 @@ static int marvell_nfc_hw_ecc_hmg_do_write_page(struct nand_chip *chip,
 		.ndcb[2] = NDCB2_ADDR5_PAGE(page),
 	};
 	unsigned int oob_bytes = lt->spare_bytes + (raw ? lt->ecc_bytes : 0);
+	u8 status;
 	int ret;
 
 	/* NFCv2 needs more information about the operation being executed */
@@ -1195,7 +1196,18 @@ static int marvell_nfc_hw_ecc_hmg_do_write_page(struct nand_chip *chip,
 
 	ret = marvell_nfc_wait_op(chip,
 				  PSEC_TO_MSEC(sdr->tPROG_max));
-	return ret;
+	if (ret)
+		return ret;
+
+	/* Check write status on the chip side */
+	ret = nand_status_op(chip, &status);
+	if (ret)
+		return ret;
+
+	if (status & NAND_STATUS_FAIL)
+		return -EIO;
+
+	return 0;
 }
 
 static int marvell_nfc_hw_ecc_hmg_write_page_raw(struct nand_chip *chip,
@@ -1624,6 +1636,7 @@ static int marvell_nfc_hw_ecc_bch_write_page(struct nand_chip *chip,
 	int data_len = lt->data_bytes;
 	int spare_len = lt->spare_bytes;
 	int chunk, ret;
+	u8 status;
 
 	marvell_nfc_select_target(chip, chip->cur_cs);
 
@@ -1660,6 +1673,14 @@ static int marvell_nfc_hw_ecc_bch_write_page(struct nand_chip *chip,
 	if (ret)
 		return ret;
 
+	/* Check write status on the chip side */
+	ret = nand_status_op(chip, &status);
+	if (ret)
+		return ret;
+
+	if (status & NAND_STATUS_FAIL)
+		return -EIO;
+
 	return 0;
 }
 
-- 
2.34.1