[PATCH 1/5] mtd/spinand: rework detect procedure for different READ_ID operation

[Dario Binacchi]

Hi Frieder, All

On Wed, May 31, 2023 at 12:58 PM Frieder Schrempf
<frieder.schrempf at kontron.de> wrote:
>
> On 17.05.23 09:43, Frieder Schrempf wrote:
> > Hi Michael, hi Dario,
> >
> > On 15.05.23 23:33, Michael Nazzareno Trimarchi wrote:
> >> Hi
> >>
> >> Il lun 15 mag 2023, 23:12 Tom Rini <trini at konsulko.com
> >> <mailto:trini at konsulko.com>> ha scritto:
> >>
> >>     On Tue, May 09, 2023 at 09:09:28AM +0200, Frieder Schrempf wrote:
> >>     > Hi Michael, hi Dario,
> >>     >
> >>     > On 18.04.23 15:46, Frieder Schrempf wrote:
> >>     > > Hi Michael, Dario,
> >>     > >
> >>     > > On 28.03.23 09:57, Frieder Schrempf wrote:
> >>     > >> Hi Michael,
> >>     > >>
> >>     > >> On 10.02.23 12:57, Michael Nazzareno Trimarchi wrote:
> >>     > >>> Hi
> >>     > >>>
> >>     > >>> I will review
> >>     > >>>
> >>     > >>> On Thu, Feb 9, 2023 at 5:52 PM Tom Rini <trini at konsulko.com
> >>     <mailto:trini at konsulko.com>> wrote:
> >>     > >>>>
> >>     > >>>> On Thu, Feb 09, 2023 at 10:24:47AM +0100, Frieder Schrempf wrote:
> >>     > >>>>> Hi,
> >>     > >>>>>
> >>     > >>>>> On 10.01.23 12:58, Frieder Schrempf wrote:
> >>     > >>>>>> From: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu
> >>     <mailto:mikhail.kshevetskiy at iopsys.eu>>
> >>     > >>>>>>
> >>     > >>>>>> Currently there are 3 different variants of read_id
> >>     implementation:
> >>     > >>>>>> 1. opcode only. Found in GD5FxGQ4xF.
> >>     > >>>>>> 2. opcode + 1 addr byte. Found in GD5GxGQ4xA/E
> >>     > >>>>>> 3. opcode + 1 dummy byte. Found in other currently
> >>     supported chips.
> >>     > >>>>>>
> >>     > >>>>>> Original implementation was for variant 1 and let detect
> >>     function
> >>     > >>>>>> of chips with variant 2 and 3 to ignore the first byte.
> >>     This isn't
> >>     > >>>>>> robust:
> >>     > >>>>>>
> >>     > >>>>>> 1. For chips of variant 2, if SPI master doesn't keep MOSI low
> >>     > >>>>>> during read, chip will get a random id offset, and the
> >>     entire id
> >>     > >>>>>> buffer will shift by that offset, causing detect failure.
> >>     > >>>>>>
> >>     > >>>>>> 2. For chips of variant 1, if it happens to get a devid
> >>     that equals
> >>     > >>>>>> to manufacture id of variant 2 or 3 chips, it'll get
> >>     incorrectly
> >>     > >>>>>> detected.
> >>     > >>>>>>
> >>     > >>>>>> This patch reworks detect procedure to address problems
> >>     above. New
> >>     > >>>>>> logic do detection for all variants separatedly, in 1-2-3
> >>     order.
> >>     > >>>>>> Since all current detect methods do exactly the same id
> >>     matching
> >>     > >>>>>> procedure, unify them into core.c and remove detect method from
> >>     > >>>>>> manufacture_ops.
> >>     > >>>>>>
> >>     > >>>>>> This is a rework of Chuanhong Guo <gch981213 at gmail.com
> >>     <mailto:gch981213 at gmail.com>> patch
> >>     > >>>>>> submitted to linux kernel
> >>     > >>>>>>
> >>     > >>>>>> Signed-off-by: Mikhail Kshevetskiy
> >>     <mikhail.kshevetskiy at iopsys.eu <mailto:mikhail.kshevetskiy at iopsys.eu>>
> >>     > >>>>>> Signed-off-by: Frieder Schrempf
> >>     <frieder.schrempf at kontron.de <mailto:frieder.schrempf at kontron.de>>
> >>     > >>>>>
> >>     > >>>>> +Cc: Jagan, Tom
> >>     > >>>>>
> >>     > >>>>> Who is supposed to pick up these patches? Some of them have
> >>     been around
> >>     > >>>>> for some months (before I resent them).
> >>     > >>>>>
> >>     > >>>>> There is no maintainer for drivers/mtd/spinand/ and no
> >>     maintainer for
> >>     > >>>>> drivers/mtd/ in general.
> >>     > >>>>>
> >>     > >>>>> In Patchwork Jagan got assigned, but the get_maintainer.pl
> >>     <http://get_maintainer.pl/> script didn't
> >>     > >>>>> even add him to Cc, of course.
> >>     > >>>>>
> >>     > >>>>> Any ideas how to proceed?
> >>     > >>>>
> >>     > >>>> We don't have anyone dedicated to that area, yes, sadly. I've
> >>     added
> >>     > >>>> Michael and Dario as they've also been doing mtd-but-not-spi
> >>     work of
> >>     > >>>> late to see if they're interested. Or since you've long been
> >>     working
> >>     > >>>> here, would you like to more formally maintain the area? Thanks!
> >>     > >>>
> >>     > >>> They can come from our tree. I will try to sort out all my
> >>     duties weeked
> >>     > >>
> >>     > >> Any news regarding reviewing/picking these patches?
> >>     > >
> >>     > > Ping!
> >>     > >
> >>     > > Can you please apply these patches, that have been waiting for
> >>     so long?
> >>     >
> >>     > I still can't see this applied anywhere. You already told me to take
> >>     > care of it multiple times. Can you please get it done?
> >>
> >>     Yes, I'd really like to see a PR at least vs -next at this point so
> >>     things aren't lost, thanks!
> >>
> >>
> >> I think that we pick already it so it will happen.
> >
> > I can see patch 1/5 of this series in the nand-next tree. What about the
> > other four patches of this series? Please pick them up, too!
>
> Ping, again! I will just keep on doing this and hope at some point you
> will pick up the patches.

Applied to nand-next.
https://source.denx.de/u-boot/custodians/u-boot-nand-flash/-/pipelines/16443

Thanks and regards
Dario
-- 

Dario Binacchi

Senior Embedded Linux Developer

dario.binacchi at amarulasolutions.com

__________________________________


Amarula Solutions SRL

Via Le Canevare 30, 31100 Treviso, Veneto, IT

T. +39 042 243 5310
info at amarulasolutions.com

www.amarulasolutions.com