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Message-ID: <75394de2-44ca-7a65-3dce-7c583b514e0a@gmail.com>
Date:   Thu, 10 Nov 2022 06:43:50 -0800
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Subject: Re: [PATCH net-next v4 4/4] net: dsa: microchip: ksz8: add MTU
 configuration support
Content-Language: en-US
To:     Oleksij Rempel <o.rempel@pengutronix.de>,
        Woojung Huh <woojung.huh@microchip.com>,
        UNGLinuxDriver@microchip.com, Andrew Lunn <andrew@lunn.ch>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
Cc:     Arun Ramadoss <arun.ramadoss@microchip.com>, kernel@pengutronix.de,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org
References: <20221110122225.1283326-1-o.rempel@pengutronix.de>
 <20221110122225.1283326-5-o.rempel@pengutronix.de>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20221110122225.1283326-5-o.rempel@pengutronix.de>
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On 11/10/2022 4:22 AM, Oleksij Rempel wrote:
> Make MTU configurable on KSZ87xx and KSZ88xx series of switches.
> 
> Before this patch, pre-configured behavior was different on different
> switch series, due to opposite meaning of the same bit:
> - KSZ87xx: Reg 4, Bit 1 - if 1, max frame size is 1532; if 0 - 1514
> - KSZ88xx: Reg 4, Bit 1 - if 1, max frame size is 1514; if 0 - 1532
> 
> Since the code was telling "... SW_LEGAL_PACKET_DISABLE, true)", I
> assume, the idea was to set max frame size to 1532.
> 
> With this patch, by setting MTU size 1500, both switch series will be
> configured to the 1532 frame limit.
> 
> This patch was tested on KSZ8873.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian