From: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Subject: Re: [PATCH 1/4] ARM: dt: mvebu: ix4-300d: remove whole flash
 partition
To: Andrew Lunn <andrew@lunn.ch>
References: <1448709248-21177-1-git-send-email-sebastian.hesselbarth@gmail.com>
 <1448709248-21177-2-git-send-email-sebastian.hesselbarth@gmail.com>
 <20151128165258.GG32356@lunn.ch>
Cc: Jason Cooper <jason@lakedaemon.net>,
        Gregory Clement <gregory.clement@free-electrons.com>,
        Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>,
        Kumar Gala <galak@codeaurora.org>,
        Russell King <linux@arm.linux.org.uk>,
        Benoit Masson <yahoo@perenite.com>,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Message-ID: <5659E687.9090502@gmail.com>
Date: Sat, 28 Nov 2015 18:38:15 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101
 Thunderbird/38.3.0
In-Reply-To: <20151128165258.GG32356@lunn.ch>
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1566
Lines: 38

On 28.11.2015 17:52, Andrew Lunn wrote:
> On Sat, Nov 28, 2015 at 12:14:05PM +0100, Sebastian Hesselbarth wrote:
>> Current NAND node has an additional flash partition for the whole
>> flash overlapping with real partitions. Remove this partition as
>> the whole flash is already represented by the NAND device itself.
> 
> If i remember correctly, we discussed this when the contribution was
> made. I think the stock firmware might use this for applying updates.
> Maybe Benoit can comment?

Yes, please.

> If so, removing this will break compatibility with stock firmware. Do
> we want to do that? There are a few other mvebu dts files with a
> partition spanning the whole flash. Should we remove them as well?

Well, there is already a mtd device that spans the whole flash so
what is the purpose of another "partition" that isn't a part but
all of the device? Actually, I doubt that a FW update will wipe
the flash as a whole, i.e. including boot loader, boot env, user
config.

Anyway, let's see if Benoit can shed some light on this.

FWIW, neither single partitions nor a combined partitions node
should be a direct sub-node of the _controller_ but a NAND
_device_ node instead. Luckily, multi-device systems are not that
common, so I guess we wait with it until such a system pops up for
testing.

Sebastian


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/