[PATCH 2/7] mtd/nand: try to erase bad blocks only if scrub flag is provided

[Mikhail Kshevetskiy]

On Thu, 6 Oct 2022 18:03:17 +0200
Michael Nazzareno Trimarchi <michael at amarulasolutions.com> wrote:

> [External email]
> 
> 
> 
> 
> 
> On Thu, Oct 6, 2022 at 5:52 PM Mikhail Kshevetskiy
> <mikhail.kshevetskiy at iopsys.eu> wrote:
> >
> > On Thu, 6 Oct 2022 08:56:08 +0200
> > Michael Nazzareno Trimarchi <michael at amarulasolutions.com> wrote:
> >
> > > [External email]
> > >
> > >
> > >
> > >
> > >
> > > Hi
> > >
> > > On Thu, Oct 6, 2022 at 5:15 AM <mikhail.kshevetskiy at iopsys.eu> wrote:
> > > >
> > > > From: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>
> > > >
> > > > 'mtd erase' command should not erase bad blocks. To force bad block
> > > > erasing there is 'mtd erase.dontskipbad' command (this command sets
> > > > 'scrub' flag to true in the erase_info structure). Unfortunately nand
> > > > layer ignore scrub flag and try to erases bad blocks unconditionally.
> > > > This is wrong.
> > > >
> > > > Add checks to allow bad block erasing only if scrub flag is set.
> > > >
> > > > Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>
> > > > ---
> > > >  drivers/mtd/nand/core.c | 5 ++++-
> > > >  1 file changed, 4 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/mtd/nand/core.c b/drivers/mtd/nand/core.c
> > > > index 99c29670c7..a4fb7602c9 100644
> > > > --- a/drivers/mtd/nand/core.c
> > > > +++ b/drivers/mtd/nand/core.c
> > > > @@ -174,7 +174,10 @@ int nanddev_mtd_erase(struct mtd_info *mtd, struct
> > > > erase_info *einfo) nanddev_offs_to_pos(nand, einfo->addr + einfo->len -
> > > > 1, &last); while (nanddev_pos_cmp(&pos, &last) <= 0) {
> > > >                 schedule();
> > > > -               ret = nanddev_erase(nand, &pos);
> > > > +               if (!einfo->scrub && nanddev_isbad(nand, &pos))
> > >
> > > The nandev_erase already check it here:
> > >
> > > if (nanddev_isbad(nand, pos) || nanddev_isreserved(nand, pos)) {
> > >
> >
> > no it does not work. see nanddev_erase() code
> >
> 
> Let me re-formulate it. What execution path are you taking into account?
> 
> The nand are erased using the cmd/nand interface and the erase command
> there calls nand_erase_opts that take in account it.

spi-nand flash

cmd/mtd.c -> do_mtd_erase() -> .... -> nanddev_mtd_erase() -> nanddev_erase()


> 
> Michael
> 
> 
> 
> The nand is erased using the
> > if block is bad or reserverved, than warning is printed, than block is
> > erased.
> >
> >
> > > > +                       ret = -EIO;
> > > > +               else
> > > > +                       ret = nanddev_erase(nand, &pos);
> > >
> > > erase opt should already take in account scrub.
> > >
> > > Please extend the problem
> > >
> > > Michael
> > > >                 if (ret) {
> > > >                         einfo->fail_addr = nanddev_pos_to_offs(nand,
> > > > &pos);
> > > >
> > > > --
> > > > 2.35.1
> > > >
> > >
> > >
> > > --
> > > Michael Nazzareno Trimarchi
> > > Co-Founder & Chief Executive Officer
> > > M. +39 347 913 2170
> > > michael at amarulasolutions.com
> > > __________________________________
> > >
> > > Amarula Solutions BV
> > > Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
> > > T. +31 (0)85 111 9172
> > > info at amarulasolutions.com
> > > https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.amarulasolutions.com%2F&data=05%7C01%7Cmikhail.kshevetskiy%40iopsys.eu%7C220e94cc3ad54f5ccca108daa7b44fe6%7C7ff78d652de440f586750569e5c7a65d%7C0%7C0%7C638006690117535825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=zTEEwU%2BKnLWNDq5xs77MmD6SI%2F31bRf3fEx%2Fyaa65%2FU%3D&reserved=0
> 
> 
> 
> --
> Michael Nazzareno Trimarchi
> Co-Founder & Chief Executive Officer
> M. +39 347 913 2170
> michael at amarulasolutions.com
> __________________________________
> 
> Amarula Solutions BV
> Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
> T. +31 (0)85 111 9172
> info at amarulasolutions.com
> https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.amarulasolutions.com%2F&data=05%7C01%7Cmikhail.kshevetskiy%40iopsys.eu%7C220e94cc3ad54f5ccca108daa7b44fe6%7C7ff78d652de440f586750569e5c7a65d%7C0%7C0%7C638006690117535825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=zTEEwU%2BKnLWNDq5xs77MmD6SI%2F31bRf3fEx%2Fyaa65%2FU%3D&reserved=0