linux-kernel - Re: [PATCH v3 5/6] dt-bindings: net: dsa: make reset optional and add rgmii-mode to mt7531

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <2509116.Lt9SDvczpP@phil>
Date:   Sun, 08 May 2022 11:41:48 +0200
From:   Heiko Stuebner <heiko@...ech.de>
To:     linux-rockchip@...ts.infradead.org,
        Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>,
        Frank Wunderlich <linux@...web.de>,
        linux-mediatek@...ts.infradead.org, frank-w@...lic-files.de
Cc:     Andrew Lunn <andrew@...n.ch>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Vladimir Oltean <olteanv@...il.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Sean Wang <sean.wang@...iatek.com>,
        Landen Chao <Landen.Chao@...iatek.com>,
        DENG Qingfang <dqfext@...il.com>,
        Peter Geis <pgwipeout@...il.com>, netdev@...r.kernel.org,
        devicetree@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, Greg Ungerer <gerg@...nel.org>,
        René van Dorst <opensource@...rst.com>,
        Mauro Carvalho Chehab <mchehab+samsung@...nel.org>
Subject: Re: [PATCH v3 5/6] dt-bindings: net: dsa: make reset optional and add rgmii-mode to mt7531

Am Sonntag, 8. Mai 2022, 08:24:37 CEST schrieb Frank Wunderlich:
> Am 7. Mai 2022 22:01:22 MESZ schrieb Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>:
> >On 07/05/2022 19:04, Frank Wunderlich wrote:
> >> From: Frank Wunderlich <frank-w@...lic-files.de>
> >> 
> >> Make reset optional as driver already supports it, 
> >
> >I do not see the connection between hardware needing or not needing a
> >reset GPIO and a driver supporting it or not... What does it mean?
> 
> My board has a shared gpio-reset between gmac and switch, so both will resetted if it is asserted. Currently it is set to the gmac and is aquired exclusive. Adding it to switch results in 2 problems:
> 
> - due to exclusive and already mapped to gmac, switch driver exits as it cannot get the reset-gpio again.
> - if i drop the reset from gmac and add to switch, it resets the gmac and this takes too long for switch to get up. Of course i can increase the wait time after reset,but dropping reset here was the easier way.
> 
> Using reset only on gmac side brings the switch up.

I think the issue is more for the description itself.

Devicetree is only meant to describe the hardware and does in general don't
care how any firmware (Linux-kernel, *BSD, etc) handles it. So going with
"the kernel does it this way" is not a valid reason for a binding change ;-) .

Instead in general want to reason that there are boards without this reset
facility and thus make it optional for those.

Heiko

> >> allow port 5 as
> >> cpu-port 
> >
> >How do you allow it here?
> 
> Argh, seems i accidentally removed this part and have not recognized while checking :(
> 
> It should only change description of reg for ports to:
> 
> "Port address described must be 5 or 6 for CPU port and from 0 to 5 for user ports."
> 
> regards Frank
>