From: Maxime Ripard <maxime.ripard@free-electrons.com>
To: Aleksei Mamlin <mamlinav@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>,
Boris Brezillon <boris.brezillon@free-electrons.com>,
Richard Weinberger <richard@nod.at>,
David Woodhouse <dwmw2@infradead.org>,
Brian Norris <computersforpeace@gmail.com>,
linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
linux-sunxi@googlegroups.com
Subject: Re: [PATCH 7/7] ARM: dts: sun7i: Enable NAND on Wexler TAB7200
Date: Fri, 10 Jun 2016 10:56:22 +0200 [thread overview]
Message-ID: <20160610085622.GO5242@lukather> (raw)
In-Reply-To: <20160609111100.38931fbe05fda9be7a355836@gmail.com>
[-- Attachment #1: Type: text/plain, Size: 3100 bytes --]
On Thu, Jun 09, 2016 at 11:11:00AM +0300, Aleksei Mamlin wrote:
> On Thu, 9 Jun 2016 00:03:14 +0200
> Maxime Ripard <maxime.ripard@free-electrons.com> wrote:
>
> > Hi,
> >
> > On Mon, Jun 06, 2016 at 01:24:24PM +0300, Aleksei Mamlin wrote:
> > > Enable the NFC and describe the NAND flash connected to this controller.
> > >
> > > Signed-off-by: Aleksei Mamlin <mamlinav@gmail.com>
> > > ---
> > > arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts | 41 ++++++++++++++++++++++++++
> > > 1 file changed, 41 insertions(+)
> > >
> > > diff --git a/arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts b/arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts
> > > index 2f6b21a..42aff91 100644
> > > --- a/arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts
> > > +++ b/arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts
> > > @@ -159,6 +159,47 @@
> > > status = "okay";
> > > };
> > >
> > > +&nfc {
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&nand_pins_a>, <&nand_cs0_pins_a>, <&nand_rb0_pins_a>;
> > > + status = "okay";
> > > +
> > > + nand@0 {
> > > + #address-cells = <2>;
> > > + #size-cells = <2>;
> > > + reg = <0>;
> > > + allwinner,rb = <0>;
> > > +
> > > + nand-ecc-mode = "hw";
> > > + nand-on-flash-bbt;
> > > +
> > > + boot0@0 {
> > > + label = "boot0";
> > > + reg = /bits/ 64 <0x0 0x200000>;
> > > + };
> > > +
> > > + boot0-rescue@200000 {
> > > + label = "boot0-rescue";
> > > + reg = /bits/ 64 <0x200000 0x200000>;
> > > + };
> > > +
> > > + uboot@400000 {
> > > + label = "uboot";
> > > + reg = /bits/ 64 <0x400000 0x200000>;
> > > + };
> > > +
> > > + uboot-rescue@600000 {
> > > + label = "uboot-rescue";
> > > + reg = /bits/ 64 <0x600000 0x200000>;
> > > + };
> > > +
> > > + main@800000 {
> > > + label = "main";
> > > + reg = /bits/ 64 <0x800000 0xff800000>;
> > > + };
> > > + };
> > > +};
> >
> > This feels a bit premature. The two boards you're using have an MLC
> > NAND which is not supported yet. Until there's proper MLC support in
> > the kernel, I'm not sure we want to enable that for end-users when we
> > know that things will get wrong.
> >
> > However, after discussing this with Boris, I appreciate that we don't
> > have any example available because of this policy for people that want
> > to opt-in anyway.
> >
> > What we could do is to still mark the status as disabled in the DTS,
> > with a big fat warning as comment just before, so that it requires
> > user action, and that user will have been warned.
> >
> > Would that work for you?
> > Maxime
> >
>
> Let's drop this two patches with boards dts changes until we get proper MLC
> support in kernel.
>
> As for examples - I'll update linux-sunxi wiki with how to enable NAND
> controller and describe NAND chips in DTS. People who want to add NAND support
> to their boards will be warned that it is risky for now.
That works for me too.
Thanks!
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
next prev parent reply other threads:[~2016-06-10 8:56 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-06 10:24 [PATCH 0/7] dts: sunxi: Add sunxi NAND Flash Controller support Aleksei Mamlin
2016-06-06 10:24 ` [PATCH 1/7] ARM: dts: sun4i: Add A10 NAND controller pin definitions Aleksei Mamlin
2016-06-08 22:04 ` Maxime Ripard
2016-06-06 10:24 ` [PATCH 2/7] ARM: dts: sun4i: Add NFC node to Allwinner A10 SoC Aleksei Mamlin
2016-06-06 10:24 ` [PATCH 3/7] ARM: dts: sun7i: Add A20 NAND controller pin definitions Aleksei Mamlin
2016-06-06 10:24 ` [PATCH 4/7] ARM: dts: sun7i: Add NFC node to Allwinner A20 SoC Aleksei Mamlin
2016-06-07 17:21 ` Aleksei Mamlin
2016-06-06 10:24 ` [PATCH 5/7] mtd: nand: Add Hynix H27UBG8T2BTR-BC to nand_ids table Aleksei Mamlin
2016-06-06 18:55 ` Boris Brezillon
2016-06-06 19:59 ` Aleksei Mamlin
2016-06-06 20:31 ` Boris Brezillon
2016-06-06 21:06 ` Aleksei Mamlin
2016-06-07 5:48 ` Boris Brezillon
2016-06-07 5:49 ` Boris Brezillon
2016-06-06 10:24 ` [PATCH 6/7] ARM: dts: sun4i: Enable NAND on Marsboard A10 Aleksei Mamlin
2016-06-06 18:50 ` Boris Brezillon
2016-06-06 10:24 ` [PATCH 7/7] ARM: dts: sun7i: Enable NAND on Wexler TAB7200 Aleksei Mamlin
2016-06-06 18:51 ` Boris Brezillon
2016-06-08 22:03 ` Maxime Ripard
2016-06-09 8:11 ` Aleksei Mamlin
2016-06-10 8:56 ` Maxime Ripard [this message]
2016-06-14 11:17 ` [PATCH v2 0/4] dts: sunxi: Add sunxi NAND Flash Controller support Aleksei Mamlin
2016-06-14 11:17 ` [PATCH v2 1/4] ARM: dts: sun4i: Add A10 NAND controller pin definitions Aleksei Mamlin
2016-06-14 12:37 ` Maxime Ripard
2016-06-14 11:17 ` [PATCH v2 2/4] ARM: dts: sun4i: Add NFC node to Allwinner A10 SoC Aleksei Mamlin
2016-06-14 12:33 ` Maxime Ripard
2016-06-14 11:17 ` [PATCH v2 3/4] ARM: dts: sun7i: Add A20 NAND controller pin definitions Aleksei Mamlin
2016-06-14 11:17 ` [PATCH v2 4/4] ARM: dts: sun7i: Add NFC node to Allwinner A20 SoC Aleksei Mamlin
2016-06-14 12:33 ` Maxime Ripard
2016-06-14 13:11 ` kbuild test robot
2016-06-14 13:19 ` Aleksei Mamlin
2016-06-14 13:57 ` Maxime Ripard
2016-06-14 14:02 ` Aleksei Mamlin
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=20160610085622.GO5242@lukather \
--to=maxime.ripard@free-electrons.com \
--cc=boris.brezillon@free-electrons.com \
--cc=computersforpeace@gmail.com \
--cc=devicetree@vger.kernel.org \
--cc=dwmw2@infradead.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mtd@lists.infradead.org \
--cc=linux-sunxi@googlegroups.com \
--cc=mamlinav@gmail.com \
--cc=richard@nod.at \
--cc=wens@csie.org \
/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).