From: JaimeLiao <jaimeliao@xxxxxxxxxxx>
Same remark as for patch 2/9.
Macronix swaps bytes on a 16-bit boundary when configured in Octal DTR.
The byte order of 16-bit words is swapped when read or written in
8D-8D-8D
mode compared to STR modes. Allow operations to specify the byte order
in
DTR mode, so that controllers can swap the bytes back at run-time to
address the flash's endianness requirements, if they are capable. If
the
controllers are not capable of swapping the bytes, the protocol is
downgrade via spi_nor_spimem_adjust_hwcaps(). When available, the
swapping
of the bytes is always done regardless if it's a data or register
access,
so that we comply with the JESD216 requirements: "Byte order of 16-bit
words is swapped when read in 8D-8D-8D mode compared to 1-1-1".
Merge Tudor's patch and add modifications for suiting newer version
of Linux kernel.
Suggested-by: Michael Walle <mwalle@xxxxxxxxxx>
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
Signed-off-by: JaimeLiao <jaimeliao@xxxxxxxxxxx>
---
drivers/mtd/spi-nor/core.c | 5 +++++
drivers/mtd/spi-nor/core.h | 1 +
2 files changed, 6 insertions(+)
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 4129764fad8c..0076007e1cde 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -113,6 +113,11 @@ void spi_nor_spimem_setup_op(const struct spi_nor
*nor,
op->cmd.opcode = (op->cmd.opcode << 8) | ext;
op->cmd.nbytes = 2;
}
+
+ /* SWAP16 is only applicable when Octal DTR mode */
+ if (nor->read_proto == SNOR_PROTO_8_8_8_DTR)
Why is it read_proto now? For all the former patches, the local
proto variable was used.
+ if (nor->flags & SNOR_F_SWAP16)
Please fold this into the former condition.
if (proto == SNOR_PROTO_8_8_8_DTR && nor->flags & SNOR_F_SWAP16)
op->data.swap16 = true;
-michael
+ op->data.swap16 = true;
}
/**
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index d36c0e072954..3c5190ac0a79 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -140,6 +140,7 @@ enum spi_nor_option_flags {
SNOR_F_RWW = BIT(14),
SNOR_F_ECC = BIT(15),
SNOR_F_NO_WP = BIT(16),
+ SNOR_F_SWAP16 = BIT(17),
};
struct spi_nor_read_command {
