[PATCH v3 0/4] spi: sophgo: Add SPI NOR controller for SG2042

[Zixian Zeng]

Add support SPI NOR flash memory controller for SG2042, using upstreamed
SG2044 SPI NOR driver.

Tested on SG2042 Pioneer Box, read, write operations.
Thanks Chen Wang who provided machine and guidance.

Signed-off-by: Zixian Zeng <sycamoremoon376 at gmail.com>
---
Changes in v3:
- Drop the patch which adds additional flash_info into gigadevice.c
- patch1: Because of the incompatibility, separate the SG2042 from the previous fallback mechanism to independent one.
- patch2: Newly add configurable options to spi-sg2044-nor driver.
- patch3: Fix reading bytes issue that causes the spi_nor_check_sfdp_signature() failure on SG2042.
- Link to v2: https://lore.kernel.org/r/20250525-sfg-spifmc-v2-0-a3732b6f5ab4@gmail.com

Changes in v2:
- patch1: Accept devicetree nodes whose compatible contains only
  "sophgo,sg2044-spifmc-nor" to avoid breaking existing devicetrees.
- patch1: Improve the commit subject message.
- patch2: Dump the SFDP information to commit message.
- Link to v1: https://lore.kernel.org/r/20250523-sfg-spifmc-v1-0-4cf16cf3fd2a@gmail.com

---
Zixian Zeng (4):
      spi: dt-bindings: spi-sg2044-nor: Change SOPHGO SG2042
      spi: spi-sg2044-nor: Add configurable chip info
      spi: spi-sg2044-nor: Fix reading bytes issue on SG2042
      riscv: dts: sophgo: Add SPI NOR node for SG2042

 .../devicetree/bindings/spi/spi-sg2044-nor.yaml    |  5 +---
 .../riscv/boot/dts/sophgo/sg2042-milkv-pioneer.dts | 24 ++++++++++++++++++
 arch/riscv/boot/dts/sophgo/sg2042.dtsi             | 24 ++++++++++++++++++
 drivers/spi/spi-sg2044-nor.c                       | 29 +++++++++++++++++++---
 4 files changed, 75 insertions(+), 7 deletions(-)
---
base-commit: 880f18ee6772d4add69519cb7de2fcf9f4769cd6
change-id: 20250523-sfg-spifmc-7a910290e964

Best regards,
-- 
Zixian Zeng <sycamoremoon376 at gmail.com>