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Message-ID: <696985ccf4a1b85a478a980fdbd3cc31fb69619a.camel@collabora.com>
Subject: Re: [PATCH v3 1/3] dt-bindings: remoteproc: k3-m4f: Add bindings
 for K3 AM64x SoCs
From:   Martyn Welch <martyn.welch@collabora.com>
To:     Mathieu Poirier <mathieu.poirier@linaro.org>,
        Hari Nagalla <hnagalla@ti.com>
Cc:     Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        kernel@collabora.com, linux-remoteproc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Fri, 24 Mar 2023 10:31:46 +0000
In-Reply-To: <20230310154145.GA1882384@p14s>
References: <20230302171450.1598576-1-martyn.welch@collabora.com>
         <20230302171450.1598576-2-martyn.welch@collabora.com>
         <20230308205833.GA1768401@p14s>
         <8662e02b-9d28-8ffa-6ec2-5cc6348933fb@ti.com>
         <20230310154145.GA1882384@p14s>
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On Fri, 2023-03-10 at 08:41 -0700, Mathieu Poirier wrote:
> On Thu, Mar 09, 2023 at 05:18:01PM -0600, Hari Nagalla wrote:
> > On 3/8/23 14:58, Mathieu Poirier wrote:
> > > > +required:
> > > > +=C2=A0 - compatible
> > > > +=C2=A0 - reg
> > > > +=C2=A0 - reg-names
> > > > +=C2=A0 - ti,sci
> > > > +=C2=A0 - ti,sci-dev-id
> > > > +=C2=A0 - ti,sci-proc-ids
> > > > +=C2=A0 - resets
> > > > +=C2=A0 - firmware-name
> > > > +=C2=A0 - mboxes
> > > The 'mboxes' property is marked as required but the description
> > > section above
> > > clearly state the M4F can operate without IPC.
> > >=20
> > Well, when the M4F is used as a safety processor it is typically
> > booted from
> > SBL/u-boot and may isolate the MCU domain from main domain/A53 to
> > function
> > in higher safety level. In these scenarios there is no remote proc
> > handling
> > of M4F life cycle management (LCM) and IPC. But, on the other hand,
> > when the
> > M4F is used as a non safety processor its LCM is handled by remote
> > proc(main
> > domain) and mailboxes for IPC are required.
>=20
> Well, what you wrote above is pretty much explained verbatim in the
> "description" section of the bindings.=C2=A0 Mailboxes are optional and a=
s
> such
> should not be found under the "required" section.
>=20

Which means the memory regions are also optional as in the isolated
case they're be no communications with the main domain.

Martyn