Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7;
MIME-Version: 1.0
References: <20230921124459.1.I91ddcfacf9b234af5cc3eabea4b62edb31153317@changeid>
 <CAL_Jsq+WuYDU+yY98opTHr1PT-J9mFYJQBjVMnk+FSWLDUO33w@mail.gmail.com>
In-Reply-To: <CAL_Jsq+WuYDU+yY98opTHr1PT-J9mFYJQBjVMnk+FSWLDUO33w@mail.gmail.com>
From:   Simon Glass <sjg@chromium.org>
Date:   Fri, 22 Sep 2023 11:01:18 -0600
Message-ID: <CAPnjgZ1pfxaMG1n5yOBhiOhsNrRjck1K92U7Ga=+VTY_jjjrVg@mail.gmail.com>
Subject: Re: [PATCH] dt-bindings: mtd: Add a schema for binman
To:     Rob Herring <robh@kernel.org>
Cc:     devicetree@vger.kernel.org,
        U-Boot Mailing List <u-boot@lists.denx.de>,
        linux-mtd@lists.infradead.org, Tom Rini <trini@konsulko.com>,
        Conor Dooley <conor+dt@kernel.org>,
        Dhruva Gole <d-gole@ti.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= <rafal@milecki.pl>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

Hi Rob,

On Fri, 22 Sept 2023 at 10:00, Rob Herring <robh@kernel.org> wrote:
>
> On Thu, Sep 21, 2023 at 1:45=E2=80=AFPM Simon Glass <sjg@chromium.org> wr=
ote:
> >
> > Binman[1] is a tool for creating firmware images. It allows you to
> > combine various binaries and place them in an output file.
> >
> > Binman uses a DT schema to describe an image, in enough detail that
> > it can be automatically built from component parts, disassembled,
> > replaced, listed, etc.
> >
> > Images are typically stored in flash, which is why this binding is
> > targeted at mtd. Previous discussion is at [2] [3].
> >
> > [1] https://u-boot.readthedocs.io/en/stable/develop/package/binman.html
> > [2] https://lore.kernel.org/u-boot/20230821180220.2724080-3-sjg@chromiu=
m.org/
> > [3] https://www.spinics.net/lists/devicetree/msg626149.html
>
> You missed:
>
> https://github.com/devicetree-org/dt-schema/pull/110
>
> where I said: We certainly shouldn't duplicate the existing partitions
> bindings. What's missing from them (I assume we're mostly talking
> about "fixed-partitions" which has been around forever I think (before
> me))?
>
> To repeat, unless there is some reason binman partitions conflict with
> fixed-partitions, you need to start there and extend it. From what's
> posted here, it neither conflicts nor needs extending.

I think at this point I am just hopelessly confused. Have you taken a
look at the binman schema? [1]

I saw this file, which seems to extend a partition.

Documentation/devicetree/bindings/mtd/partitions/brcm,bcm4908-partitions.ya=
ml

I was assuming that I should create a top-level compatible =3D "binman"
node, with subnodes like compatible =3D "binman,bl31-atf", for example.
I should use the compatible string to indicate the contents, right?

Re extending, what is the minimum I can do? Are you looking for
something like a "compress" property that indicates that the entry is
compressed?

I'm really just a bit lost.

>
> I did a bit more research. "fixed-partitions" as a compatible has
> "only" been around since 2015. Prior to that, it was implicit with
> just partition nodes with addresses (i.e. reg) and that dates back to
> 2007. Looks like u-boot only supports the newer form and since 2021.

OK

Regards,
Simon

[1] https://u-boot.readthedocs.io/en/latest/develop/package/binman.html#ima=
ge-description-format