[PATCH v6 0/3] Meson: R/W support for pages used by boot ROM

[Arseniy Krasnov]

Amlogic's boot ROM code needs that some pages on NAND must be written
in special "short" ECC mode with scrambling enabled. Such pages:
1) Contain some metadata about hardware.
2) Located with some interval starting from 0 offset, until some
   specified offset. Interval and second offset are set in the
   device tree.

This patchset adds R/W support for such pages. To enable it we can setup
it in dts:

    nand-is-boot-medium;
    amlogic,boot-pages = <1024>;
    amlogic,boot-page-step = <128>;

It means that each 128th page in range 0 to 1024 pages will be accessed
in special mode ("short" ECC + scrambling). In practice this feature is
needed when we want to update first block of NAND - driver will enable
required mode by itself using value from device tree.

Changelog:
 v1 -> v2:
  * Rename 'meson,boot-page-XXX' -> 'amlogic,boot-page-XXX'.
  * Add words that 'amlogic,boot-page-step' is measured in pages.
  * Remove words that 'amlogic,boot-page-XXX' depends on 'nand-is-boot-medium'.
  * Make both 'amlogic,boot-page-XXX' depend on each other also, in
    addition to 'nand-is-boot-medium' dependency.
 v2 -> v3:
  * Add quotes to 0001 in dependencies. This fixes 'make dt_binding_check'
    warning.
 v3 -> v4:
  * Rename 'amlogic,boot-page-last' to 'amlogic,boot-pages'.
 v4 -> v5:
  * Update 'description' fields in bindings.
 v5 -> v6:
  * Split patch for meson_nand.c to 2 patches: first is refactoring of
    scrambling mode handling, another is support for special pages for
    boot ROM.
  * Update description and commit message in the bindings patch.

Arseniy Krasnov (3):
  dt-bindings: mtd: amlogic,meson-nand: support fields for boot ROM code
  mtd: rawnand: meson: refactor use of 'meson_nfc_cmd_access()'
  mtd: rawnand: meson: read/write access for boot ROM pages

 .../bindings/mtd/amlogic,meson-nand.yaml      | 18 ++++
 drivers/mtd/nand/raw/meson_nand.c             | 86 +++++++++++++------
 2 files changed, 77 insertions(+), 27 deletions(-)

-- 
2.35.0