[PATCH v2 2/2] mtd: nand: raw: denali: Wait for reset completion status

[Ley Foon Tan <ley.foon.tan@intel.com>]

Fixed delay 200us is not working in certain platforms. Change to
poll for reset completion status to have more reliable reset process.

Controller will set the rst_comp bit in intr_status register after
controller has completed its reset and initialization process.

Tested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Radu Bacrau <radu.bacrau@intel.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>

---
v2:
- Added "Tested-by" in commit message.
- Restore "bootstrap process" in comment.
---
 drivers/mtd/nand/raw/denali.c    | 11 +++++++++++
 drivers/mtd/nand/raw/denali.h    |  1 +
 drivers/mtd/nand/raw/denali_dt.c | 11 ++++++++---
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c
index 15e90291de09..ab91db85467d 100644
--- a/drivers/mtd/nand/raw/denali.c
+++ b/drivers/mtd/nand/raw/denali.c
@@ -1220,6 +1220,17 @@ static int denali_multidev_fixup(struct denali_nand_info *denali)
 	return 0;
 }
 
+int denali_wait_reset_complete(struct denali_nand_info *denali)
+{
+	u32 irq_status;
+
+	irq_status = denali_wait_for_irq(denali, INTR__RST_COMP);
+	if (!(irq_status & INTR__RST_COMP))
+		return -EIO;
+
+	return 0;
+}
+
 int denali_init(struct denali_nand_info *denali)
 {
 	struct nand_chip *chip = &denali->nand;
diff --git a/drivers/mtd/nand/raw/denali.h b/drivers/mtd/nand/raw/denali.h
index 019deda094e5..6cd02b2e26ee 100644
--- a/drivers/mtd/nand/raw/denali.h
+++ b/drivers/mtd/nand/raw/denali.h
@@ -321,6 +321,7 @@ struct denali_nand_info {
 #define DENALI_CAP_DMA_64BIT			BIT(1)
 
 int denali_calc_ecc_bytes(int step_size, int strength);
+int denali_wait_reset_complete(struct denali_nand_info *denali);
 int denali_init(struct denali_nand_info *denali);
 
 #endif /* __DENALI_H__ */
diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c
index 75ad15b0758c..c22b05940df6 100644
--- a/drivers/mtd/nand/raw/denali_dt.c
+++ b/drivers/mtd/nand/raw/denali_dt.c
@@ -154,10 +154,15 @@ static int denali_dt_probe(struct udevice *dev)
 
 		/*
 		 * When the reset is deasserted, the initialization sequence is
-		 * kicked (bootstrap process). The driver must wait until it is
-		 * finished. Otherwise, it will result in unpredictable behavior.
+		 * kicked (bootstrap proccess). The driver must wait until it
+		 * is finished. Otherwise, it will result in unpredictable
+		 * behavior.
 		 */
-		udelay(200);
+		ret = denali_wait_reset_complete(denali);
+		if (ret) {
+			dev_err(denali->dev, "reset not completed.\n");
+			return ret;
+		}
 	}
 
 	return denali_init(denali);
-- 
2.19.0