On 2020-10-28 15:18, Miquel Raynal wrote:
Hello,
Md Sadre Alam <mdalam@xxxxxxxxxxxxxx> wrote on Sat, 10 Oct 2020
11:01:37 +0530:
QPIC 2.0 supports Serial NAND support in addition to all features and
commands in QPIC 1.0 for parallel NAND. Parallel and Serial NAND
cannot
operate simultaneously. QSPI nand devices will connect to QPIC
IO_MACRO
block of QPIC controller. There is a separate IO_MACRO clock for
IO_MACRO
block. Default IO_MACRO block divide the input clock by 4. so if
IO_MACRO
input clock is 320MHz then on bus it will be 80MHz, so QSPI nand
device
should also support this frequency.
QPIC provides 4 data pins to QSPI nand. In standard SPI mode (x1 mode)
data
transfer will occur on only 2 pins one pin for Serial data in and one
for
serial data out. In QUAD SPI mode (x4 mode) data transfer will occur
at all
the four data lines. QPIC controller supports command for x1 mode and
x4 mode.
Md Sadre Alam (5):
dt-bindings: qcom_nandc: IPQ5018 QPIC NAND documentation
mtd: rawnand: qcom: Add initial support for qspi nand
mtd: rawnand: qcom: Read QPIC version
mtd: rawnand: qcom: Enable support for erase,read & write for serial
nand.
mtd: rawnand: qcom: Add support for serial training.
.../devicetree/bindings/mtd/qcom_nandc.txt | 3 +
drivers/mtd/nand/raw/nand_ids.c | 13 +
drivers/mtd/nand/raw/qcom_nandc.c | 502
++++++++++++++++++++-
3 files changed, 494 insertions(+), 24 deletions(-)
I'm sorry but this series clearly breaks the current layering. I cannot
authorize SPI-NAND code to fall into the raw NAND subsystem.
I am agree with you, we should not add SPI-NAND changes inside
raw NAND subsystem.
As both typologies cannot be used at the same time, I guess you should
have another driver handling this feature under the spi/ subsystem +
a few declarations in the SPI-NAND devices list.
Initially I was started writing separate driver under SPI-NAND subsystem
then I
realized that more than 85% of raw/qcom_nand.c code getting duplicated.
That's why I have added this SPI-NAND change in raw/qcom_nand.c since
more than 85% of code will be reused.
If I will add this change inside SPI-NAND subsystem then much of
raw/qcom_nand.c code will get duplicated. Would it be ok ?
Thanks,
Miquèl
