From: Miquel Raynal <miquel.raynal@bootlin.com>
To: "Shivamurthy Shastri (sshivamurthy)" <sshivamurthy@micron.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>,
Boris Brezillon <bbrezillon@kernel.org>,
Shivamurthy Shastri <shiva.linuxworks@gmail.com>,
Richard Weinberger <richard@nod.at>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Frieder Schrempf <frieder.schrempf@kontron.de>,
"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Subject: Re: [EXT] Re: [PATCH 3/4] mtd: spinand: Add M70A series Micron SPI NAND devices
Date: Tue, 21 Jan 2020 14:40:34 +0100 [thread overview]
Message-ID: <20200121144034.05a8f49d@xps13> (raw)
In-Reply-To: <MN2PR08MB6397062A37D39287E820A0D8B80D0@MN2PR08MB6397.namprd08.prod.outlook.com>
Hi Shivamurthy,
"Shivamurthy Shastri (sshivamurthy)" <sshivamurthy@micron.com> wrote on
Tue, 21 Jan 2020 12:23:20 +0000:
> Hi Miquel,
>
> >
> > Hi Shiva,
> >
> > This is remark common to the four patches: you miss the 'v2' prefix in
> > the object.
> >
>
> Sorry for this mistake.
> I recognized this after sending out the patches.
>
> > shiva.linuxworks@gmail.com wrote on Sun, 19 Jan 2020 15:54:31 +0100:
> >
> > > From: Shivamurthy Shastri <sshivamurthy@micron.com>
> > >
> > > Add device table for M70A series Micron SPI NAND devices.
> > >
> > > While at it, disable the Continuous Read feature which is enabled by
> > > default.
> >
> > Can you please give us more detail on why this is an issue?
>
> "Continuous Read" is the new feature added by the Micron for
> M70A series devices. If this feature is enabled, the READ command
> doesn't output the OOB area. The following short description
> describes this feature.
>
> Description:
> If the Continuous Read feature is enabled, the device provides
> the capability to read the whole block with a single command.
> However, the read command doesn't output the OOB area.
>
> Read command behavior (if Continuous Read enabled):
> The READ CACHE command doesn't require the starting column address.
> The device always output the data starting from the first column of the
> cache register, and once the end of the cache register reached, the data
> output continues through the next page. With the continuous read mode,
> it is possible to read out the entire block using a single READ command, and
> once the end of the block reached, the output pins become High-Z state.
Ok I understand better. In this case there is no need to split this
commit, instead just reword the commit log to something like:
--->8---
Add device table for M70A series Micron SPI-NAND devices.
As opposed to the M60A series already supported, M70A parts have the
"Continuous Read" feature enabled by default which does not fit the
subsystem needs.
<here explain the feature>.
Hence, we disable the feature at probe time.
---8<---
However, below, you disable this bit for all the parts. Is this really
ok? Souldn't we make it more specific to this series?
>
> >
> > Shall we backport it to stable?
>
> This is not a bug fix and applicable only to M70A series devices, there is no
> need to backport.
> (FYI, the previously enabled device was M79A series)
>
> >
> > As a rule of thumb, when you start a sentence by "while at it" in a
> > commit message and this is not a trivial change : split the patch,
> > please. Unless this is really related and in this case explain how and
> > why in the commit message.
>
> Okay, I will explain in my next version.
>
> >
> > >
> > > Signed-off-by: Shivamurthy Shastri <sshivamurthy@micron.com>
> > > ---
> > > drivers/mtd/nand/spi/micron.c | 31
> > +++++++++++++++++++++++++++++++
> > > 1 file changed, 31 insertions(+)
> > >
> > > diff --git a/drivers/mtd/nand/spi/micron.c
> > b/drivers/mtd/nand/spi/micron.c
> > > index 5fd1f921ef12..45fc37c58f8a 100644
> > > --- a/drivers/mtd/nand/spi/micron.c
> > > +++ b/drivers/mtd/nand/spi/micron.c
> > > @@ -131,6 +131,26 @@ static const struct spinand_info
> > micron_spinand_table[] = {
> > > 0,
> > > SPINAND_ECCINFO(µn_8_ooblayout,
> > > micron_8_ecc_get_status)),
> > > + /* M70A 4Gb 3.3V */
> > > + SPINAND_INFO("MT29F4G01ABAFD", 0x34,
> > > + NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 1, 1, 1),
> > > + NAND_ECCREQ(8, 512),
> > > + SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
> > > + &write_cache_variants,
> > > + &update_cache_variants),
> > > + 0,
> > > + SPINAND_ECCINFO(µn_8_ooblayout,
> > > + micron_8_ecc_get_status)),
> > > + /* M70A 4Gb 1.8V */
> > > + SPINAND_INFO("MT29F4G01ABBFD", 0x35,
> > > + NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 1, 1, 1),
> > > + NAND_ECCREQ(8, 512),
> > > + SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
> > > + &write_cache_variants,
> > > + &update_cache_variants),
> > > + 0,
> > > + SPINAND_ECCINFO(µn_8_ooblayout,
> > > + micron_8_ecc_get_status)),
> > > };
> > >
> > > static int micron_spinand_detect(struct spinand_device *spinand)
> > > @@ -153,8 +173,19 @@ static int micron_spinand_detect(struct
> > spinand_device *spinand)
> > > return 1;
> > > }
> > >
> > > +static int micron_spinand_init(struct spinand_device *spinand)
> > > +{
> > > + /*
> > > + * M70A device series enable Continuous Read feature at Power-up,
> > > + * which is not supported. Disable this bit to avoid any possible
> > > + * failure.
> > > + */
> > > + return spinand_upd_cfg(spinand, CFG_QUAD_ENABLE, 0);
> > > +}
> > > +
> > > static const struct spinand_manufacturer_ops
> > micron_spinand_manuf_ops = {
> > > .detect = micron_spinand_detect,
> > > + .init = micron_spinand_init,
> > > };
> > >
> > > const struct spinand_manufacturer micron_spinand_manufacturer = {
> >
> > Thanks,
> > Miquèl
>
> Thanks,
> Shiva
Thanks,
Miquèl
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
next prev parent reply other threads:[~2020-01-21 13:41 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-19 14:54 [PATCH 0/4] Add new series Micron SPI NAND devices shiva.linuxworks
2020-01-19 14:54 ` [PATCH 1/4] mtd: spinand: Generalize the OOB layout structure and function names shiva.linuxworks
2020-01-30 8:30 ` Miquel Raynal
2020-01-19 14:54 ` [PATCH 2/4] mtd: spinand: Add new Micron SPI NAND devices shiva.linuxworks
2020-01-19 14:54 ` [PATCH 3/4] mtd: spinand: Add M70A series " shiva.linuxworks
2020-01-20 10:16 ` Miquel Raynal
2020-01-21 12:23 ` [EXT] " Shivamurthy Shastri (sshivamurthy)
2020-01-21 13:40 ` Miquel Raynal [this message]
2020-01-21 14:59 ` Shivamurthy Shastri (sshivamurthy)
2020-01-21 15:27 ` Miquel Raynal
2020-01-23 9:01 ` Shivamurthy Shastri (sshivamurthy)
2020-01-19 14:54 ` [PATCH 4/4] mtd: spinand: Add new Micron SPI NAND devices with multiple dies shiva.linuxworks
2020-01-20 10:22 ` Miquel Raynal
2020-01-21 12:23 ` [EXT] " Shivamurthy Shastri (sshivamurthy)
2020-01-21 13:44 ` Miquel Raynal
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200121144034.05a8f49d@xps13 \
--to=miquel.raynal@bootlin.com \
--cc=bbrezillon@kernel.org \
--cc=frieder.schrempf@kontron.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mtd@lists.infradead.org \
--cc=richard@nod.at \
--cc=shiva.linuxworks@gmail.com \
--cc=sshivamurthy@micron.com \
--cc=vigneshr@ti.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).