[PATCH v5] mtd: spi-nor: add driver for NXP SPI Flash Interface (SPIFI)

[Joachim Eastwood]

Hi Brian,

On 13 August 2015 at 23:47, Brian Norris <computersforpeace at gmail.com> wrote:
> On Thu, Aug 13, 2015 at 07:19:40PM +0200, Joachim Eastwood wrote:
>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>> controller that is found on newer NXP MCU devices.
>>
>> The controller supports serial SPI Flash devices with 1-, 2-
>> and 4-bit width in either SPI mode 0 or 3. The controller
>> can operate in either command or memory mode. In memory mode
>> the Flash is exposed as normal memory and can be directly
>> accessed by the CPU.
>>
>> Signed-off-by: Joachim Eastwood <manabian at gmail.com>
>> Reviewed-by: Ezequiel Garcia <ezequiel at vanguardiasur.com.ar>
>> ---
>> Hi Brian,
>>
>> I skipped the cover letter since you already applied the 2nd
>> of patch of the original set and using a cover letter for
>> just one patch seemed a bit useless. Cover letter for v4 can
>> be found here: http://marc.info/?l=devicetree&m=143647330431908&w=2
>>
>> This version address all comments from Brian Norris except
>> for two things noted below.
>>
>> If the line below is removed the kernel opses on jffs2 mount.
>> spifi->mtd.priv  = &spifi->nor;
>> It seems like spi-nor.c doesn't setup this field. fsl-quadspi
>> also assigns this field, btw.
>
> Sorry, I overlooked that. But that code's pretty dumb. I'll take yours
> as-is, but I'll send a patch to fix both.

OK.

>> The read/wait ordering in nxp_spifi_read_reg is correct. I
>> don't really have a good explaination for the ordering. The
>> user manual doesn't document the SPIFI in detail, but the
>> offcial NXP spifilib has the same ordering.
>
> OK, no problem.
>
>> Changes since v4:
>>  - spifi: always autodetect SPI Flash
>>  - s/spi/SPI on dev_* output
>>  - add parentheses to SPIFI_CMD_DATALEN macro
>>  - rebase on mtd-master
>>
>> Changes since v3:
>>  - fix bug in write function
>>  - rebase on 4.2-rc1
>>
>> Changes since v2:
>>  - default to auto detection unless chip is specified
>>  - update doc with reference to jedec,spi-nor.txt
>>
>> Test on the following boards.
>> Hitex board boots on SPIFI Flash with JFFS2.
>>
>> Hitex LPC4350 Eval board:
>> [    2.093956] nxp-spifi 40003000.spifi: s25sl064p (8192 Kbytes)
>>
>> Embedded Artists' LPC4357 Developer's Kit:
>> [    3.051627] nxp-spifi 40003000.spifi: s25fl016k (2048 Kbytes)
>
> Applied to l2-mtd.git, thanks!

Excellent. Thanks Brian.

> BTW, is this driver worth a MAINTAINERS entry? It's nice to always have
> someone on CC that has the hardware. The git history should probably
> pick you up anyway when running get_maintainers.pl, so it may not be
> absolutely necessary.

Sure. I can add it under the main lpc18xx platform entry in
MAINTAINERS. I'll queue up a patch for arm-soc.

>> Both s25fl016k and s25sl064p support dual/quad mode, but this
>> is not flagged in spi-nor.c. I have sent a patch for s25fl016k
>> and will send a patch s25sl064p please apply when you get them.
>
> I'll see if I can dig these out of the mailing list eventually. I have a
> sizable backlog.

Ok, thanks.


regards,
Joachim Eastwood