CFI/JEDEC parallel NOR flash and ROM/RAM chip drivers
Core support for parallel NOR flash memory chips wired directly to a CPU's memory bus, covering the standard command sets used by Intel/Sharp, AMD/Fujitsu/Spansion, and ST chips, plus simpler mapped ROM and RAM. This flash was ubiquitous in 1990s and 2000s embedded boards, routers, and BIOS chips, and still ships in industrial systems needing small execute-in-place memory.
recommendation
Worth keeping but documenting as legacy/niche hardware. Vendors like Macronix still sell parallel NOR flash families new in 2025 for industrial and embedded use, and the code continues to receive low-volume maintenance patches on linux-mtd as recently as late 2024, so it is neither abandoned nor targeted for removal. It is no longer strategic-growth hardware, however, since most modern designs have moved to SPI NOR or NAND.
repository signals
sources
- git.kernel.org
Kconfig describes this directory as 'RAM/ROM/Flash chip drivers' and lists CFI, JEDEC, Intel/Sharp, AMD/Fujitsu/Spansion, STAA, RAM, ROM, and absent-chip support.
- lore.kernel.org
linux-mtd still sees direct patches against this code in late 2024, indicating maintenance rather than abandonment or active removal.
- lore.kernel.org
The directory was still touched in 2026 via treewide maintenance, so it is not dormant in upstream.
- macronix.com
Macronix still markets multiple Parallel NOR Flash families (MX29F/MX29LV/MX29GL/MX29GA/etc.), showing that the hardware class remains commercially available in 2025-era catalogs.
codex reasoning notes (technical)
Real driver directory, not helpers-only: local source inspection showed probe/registration code and chip-driver modules for CFI/JEDEC flash plus ROM/RAM map chips. Kernel Kconfig URL is a canonical kernel.org recall. Both lore URLs were obtained via `lore_file_timeline` on `drivers/mtd/chips/cfi_cmdset_0002.c`; they show ongoing but mostly low-volume janitorial/treewide maintenance and no removal campaign. The Macronix URL was obtained via web search and supports 'still sold' for parallel NOR as an industrial/embedded niche. Conclusion: keep upstream, but annotate as legacy/niche rather than strategic-growth hardware.