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Message-ID: <70a44baa-4a1c-9c9e-6781-b1b563c787bd@gmail.com>
Date:   Tue, 25 Jan 2022 19:54:15 -0800
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Subject: Re: [RFC PATCH v7 06/16] net: dsa: tag_qca: add define for handling
 mgmt Ethernet packet
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To:     Ansuel Smith <ansuelsmth@gmail.com>, Andrew Lunn <andrew@lunn.ch>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org
References: <20220123013337.20945-1-ansuelsmth@gmail.com>
 <20220123013337.20945-7-ansuelsmth@gmail.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20220123013337.20945-7-ansuelsmth@gmail.com>
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On 1/22/2022 5:33 PM, Ansuel Smith wrote:
> Add all the required define to prepare support for mgmt read/write in
> Ethernet packet. Any packet of this type has to be dropped as the only
> use of these special packet is receive ack for an mgmt write request or
> receive data for an mgmt read request.
> A struct is used that emulates the Ethernet header but is used for a
> different purpose.
> 
> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> ---

[snip]

> +/* Special struct emulating a Ethernet header */
> +struct mgmt_ethhdr {
> +	u32 command;		/* command bit 31:0 */
> +	u32 seq;		/* seq 63:32 */
> +	u32 mdio_data;		/* first 4byte mdio */
> +	__be16 hdr;		/* qca hdr */
> +} __packed;

Might be worth adding a BUILD_BUG_ON(sizeof(struct mgmt_ethhdr) != 
QCA_HDR_MGMT_PKG_LEN) when you start making use of that structure?
-- 
Florian