Re: [PATCH v3 0/9] BCMA support for brcmnand

[Kamal Dasu <kdasu.kdev@gmail.com>]

Florian,

On Fri, Jan 7, 2022 at 1:46 PM Florian Fainelli <f.fainelli@gmail.com> wrote:
>
> Hi all,
>
> This patch series adds support for the BRCMNAND controller revision 3.4
> embedded in MIPS-based SoCs such as 5357, typically found in the Netgear
> WNR3500L v2 and other kinds of Wi-Fi routers. The upstream platform that
> uses this controller is under arch/mips/bcm47xx/ and does not use Device
> Tree (and probably never will by now). BCMA (Broadcom AMBA) is a special
> kind of discoverable memory mapped interface which requires the use of
> special accessors to read from/write to the hardware block.
>
> The integration of brcmnand into that SoC is a bit quirky in that every
> register offering byte level data about the flash (OOB, device ID, etc.)
> requires byte swapping. The command shift should also have been 24, but
> is in fact 0, took me a while to understand why no reads were actually
> working because of that.
>
> This has been tested with Linux 5.10.82 and Linus' master with OpenWrt
> and confirmed that the squashfs + jffs2 overlay that OpenWrt creates is
> entirely functional and that written data is made persistent.
>
> Changes in v3:
>
> - fixed a few typo/grammar errors in the commit messages, mention when
>   changes are non functional changes
> - removed the stray hunk in 2 to enable the static key
>
> Changes in v2:
>
> - re-ordered the patch such that the soc variable is initialized as
>   early as possible
> - corrected bug in the conversion of brcmnand_init_cs() which
>   incorrectly used the wrong device_node variable (parent instead of
>   child)
> - took Andy's feedback to make the test for a valid interrupt to be > 0
>   while calling platform_get_irq_optional()
> - utilized static branch (disabled by default) and conditional
>   compilation and confirm with disassembly that the generated code is
>   as efficient as before if not enabling the BCMA shim and as efficient
>   as possible if enabling BCMA shim
> - updated BCMA shim driver descriptor, author and added helper function
>   to encapsulate the container_of usage
> - added comment to explain why a slightly different platform device name
>   is used for the 5357-style NAND controller
>
> Florian Fainelli (9):
>   mtd: rawnand: brcmnand: Assign soc as early as possible
>   mtd: rawnand: brcmnand: Allow SoC to provide I/O operations
>   mtd: rawnand: brcmnand: Avoid pdev in brcmnand_init_cs()
>   mtd: rawnand: brcmnand: Move OF operations out of brcmnand_init_cs()
>   mtd: rawnand: brcmnand: Allow working without interrupts
>   mtd: rawnand: brcmnand: Add platform data structure for BCMA
>   mtd: rawnand: brcmnand: Allow platform data instantation
>   mtd: rawnand: brcmnand: BCMA controller uses command shift of 0
>   mtd: rawnand: brcmnand: Add BCMA shim
>
>  MAINTAINERS                                 |   1 +
>  drivers/bcma/driver_chipcommon_nflash.c     |  20 ++-
>  drivers/mtd/nand/raw/Kconfig                |  13 ++
>  drivers/mtd/nand/raw/brcmnand/Makefile      |   2 +
>  drivers/mtd/nand/raw/brcmnand/bcma_nand.c   | 132 ++++++++++++++++
>  drivers/mtd/nand/raw/brcmnand/brcmnand.c    | 160 +++++++++++++-------
>  drivers/mtd/nand/raw/brcmnand/brcmnand.h    |  29 ++++
>  include/linux/bcma/bcma_driver_chipcommon.h |   5 +
>  include/linux/platform_data/brcmnand.h      |  12 ++
>  9 files changed, 321 insertions(+), 53 deletions(-)
>  create mode 100644 drivers/mtd/nand/raw/brcmnand/bcma_nand.c
>  create mode 100644 include/linux/platform_data/brcmnand.h
>
> --
> 2.25.1
>

The patch series as in v3  LGTM

Kamal