[PATCH 08/10] mtd: rawnand: onfi: Add an alternative parameter page read

[Miquel Raynal <miquel.raynal@xxxxxxxxxxx>]

Some controllers are not able to read the parameter page in separate chunks.

As there is no need for separate parameter page reads (the delay penalty
for reading the three copies in one go being negligible), the
temptation to just do a monolithic read is high.

But we are afraid of controllers not supporting reading a parameter
page of 768 bytes neither.

So, despite darkening a little bit this portion, the final solution to
support as many controllers as possible is to check if there is an
actual need for such monolithic read, otherwise we keep the current
behavior.

Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
---
 drivers/mtd/nand/raw/nand_onfi.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/raw/nand_onfi.c b/drivers/mtd/nand/raw/nand_onfi.c
index 2fc71b7c361f..e6be19e1afde 100644
--- a/drivers/mtd/nand/raw/nand_onfi.c
+++ b/drivers/mtd/nand/raw/nand_onfi.c
@@ -160,17 +160,24 @@ int nand_onfi_detect(struct nand_chip *chip)
 	if (!pbuf)
 		return -ENOMEM;
 
-	ret = nand_read_param_page_op(chip, 0, NULL, 0);
+	if (nand_pack_ops(chip))
+		ret = nand_read_param_page_op(chip, 0, pbuf,
+					      sizeof(*pbuf) * ONFI_PARAM_PAGES);
+	else
+		ret = nand_read_param_page_op(chip, 0, NULL, 0);
 	if (ret) {
 		ret = 0;
 		goto free_onfi_param_page;
 	}
 
 	for (i = 0; i < ONFI_PARAM_PAGES; i++) {
-		ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf), true);
-		if (ret) {
-			ret = 0;
-			goto free_onfi_param_page;
+		if (!nand_pack_ops(chip)) {
+			ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf),
+						true);
+			if (ret) {
+				ret = 0;
+				goto free_onfi_param_page;
+			}
 		}
 
 		crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
-- 
2.20.1


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