[RFC,v2 0/4] Add a driver for Mediatek SPI Nand controller

[Xiangsheng Hou]

Add a driver for Mediatek SPI Nand controller

Mediatek SPI Nand controller cosists of two parts: on-host HW ECC and
snfi(stand for spi nand flash interface). They can cowork with high
performance which called ECC nfi mode. The nfi stand for nand flash
interfacei(snfi a one part of nfi) which can support SPI Nand flash
and raw nand flash.

However, the snfi driver in spi subsytem need to be aware of nand
parameter(page/spare size) and ecc status(enable/disable) when work
at ECC nfi mode. The snfi driver in spi subsystem seems difficult to
know these.

Therefore, consider two ways to let snfi can get these information.
The RFC patch send to review whether they are suitable and which
solution maybe better.

RFC patch v1:
Add nfi register base at bch(ecc) dts node and config nand parameter
and ecc status into nfi registers in ecc driver, then parse these
information at snfi driver to use.

RFC patch v2:
Export some function in HW ECC driver and snfi driver.
In HW ECC driver, export function include get nand page/spare size, HW
ECC status(enable/disable) and fdm(oob free per sector in ooblayout) size.
In snfi driver need export empty page status which the nfi can be aware
when in ECC nfi mode(the spim framework can not return this information).

This series patch is the v2 solution, and only take mt7622 board for dts
node example.

Xiangsheng Hou (4):
  mtd: ecc: move mediatek HW ECC driver
  mtd: ecc: realize Mediatek HW ECC driver
  spi: add Mediatek SPI Nand controller driver
  arm64: dts: add snfi node for spi nand

 arch/arm64/boot/dts/mediatek/mt7622-rfb1.dts  |   17 +
 arch/arm64/boot/dts/mediatek/mt7622.dtsi      |   13 +
 drivers/mtd/nand/Kconfig                      |    9 +
 drivers/mtd/nand/Makefile                     |    1 +
 drivers/mtd/nand/core.c                       |    2 +-
 drivers/mtd/nand/ecc.c                        |   19 +
 drivers/mtd/nand/{raw => }/mtk_ecc.c          |  317 ++++-
 drivers/mtd/nand/raw/Kconfig                  |    1 +
 drivers/mtd/nand/raw/Makefile                 |    2 +-
 drivers/mtd/nand/raw/mtk_nand.c               |    2 +-
 drivers/spi/Kconfig                           |   11 +
 drivers/spi/Makefile                          |    1 +
 drivers/spi/spi-mtk-snfi.c                    | 1087 +++++++++++++++++
 .../nand/raw => include/linux/mtd}/mtk_ecc.h  |    0
 include/linux/mtd/nand.h                      |   12 +
 15 files changed, 1490 insertions(+), 4 deletions(-)
 rename drivers/mtd/nand/{raw => }/mtk_ecc.c (65%)
 create mode 100644 drivers/spi/spi-mtk-snfi.c
 rename {drivers/mtd/nand/raw => include/linux/mtd}/mtk_ecc.h (100%)

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2.25.1