[PATCH] mtd: spi-nor: Fix the qspi parallel memory issues

[Venkatesh Yadav Abbarapu]

The below issues are fixed
1)Fix the read issue for 4byte address width as read_len
is getting zero.
2)Fix the spi_nor_erase function by passing the
correct offset when it is configured as dual parallel.
3)Update the write_bar() only if the address width is 3byte for
spi_nor_erase() function.

ZynqMP> sf read 0x4000000 0 100000
device 0 offset 0x0, size 0x100000
SF: 1048576 bytes @ 0x0 Read: ERROR -5

Fixes: 5d40b3d384 ("mtd: spi-nor: Add parallel and stacked memories support")
Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu at amd.com>
---
 drivers/mtd/spi/spi-nor-core.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index f5c9868bbc..2034d84251 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -1141,11 +1141,14 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
 				nor->spi->flags &= ~SPI_XFER_U_PAGE;
 			}
 		}
+		if (nor->addr_width == 3) {
 #ifdef CONFIG_SPI_FLASH_BAR
-		ret = write_bar(nor, addr);
-		if (ret < 0)
-			goto erase_err;
+			ret = write_bar(nor, offset);
+			if (ret < 0)
+				goto erase_err;
 #endif
+		}
+
 		ret = write_enable(nor);
 		if (ret < 0)
 			goto erase_err;
@@ -1154,7 +1157,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
 		    !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
 			ret = spi_nor_erase_chip(nor);
 		} else {
-			ret = spi_nor_erase_sector(nor, addr);
+			ret = spi_nor_erase_sector(nor, offset);
 		}
 		if (ret < 0)
 			goto erase_err;
@@ -1582,6 +1585,7 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
 	loff_t offset = from;
 	u32 read_len = 0;
 	u32 rem_bank_len = 0;
+	u32 stack_shift = 0;
 	u8 bank;
 	bool is_ofst_odd = false;
 
@@ -1608,6 +1612,7 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
 		offset = from;
 
 		if (nor->flags & SNOR_F_HAS_STACKED) {
+			stack_shift = 1;
 			if (offset >= (mtd->size / 2)) {
 				offset = offset - (mtd->size / 2);
 				nor->spi->flags |= SPI_XFER_U_PAGE;
@@ -1616,6 +1621,10 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
 			}
 		}
 
+		if (nor->addr_width == 4)
+			rem_bank_len = (mtd->size >> stack_shift) -
+					offset;
+
 		if (nor->flags & SNOR_F_HAS_PARALLEL)
 			offset /= 2;
 
-- 
2.17.1