Date:   Fri, 10 Mar 2023 17:25:58 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc:     Lukasz Majewski <lukma@denx.de>, Andrew Lunn <andrew@lunn.ch>,
        Eric Dumazet <edumazet@google.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Alexander Duyck <alexander.duyck@gmail.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/7] dsa: marvell: Correct value of max_frame_size
 variable after validation
Message-ID: <20230310152558.3ko7ufns4jexdkx7@skbuf>
References: <20230309125421.3900962-1-lukma@denx.de>
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 <20230309154350.0bdc54c8@wsk>
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 <20230310125346.13f93f78@wsk>
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On Fri, Mar 10, 2023 at 12:06:15PM +0000, Russell King (Oracle) wrote:
> It may be worth doing:
> 
> static int mv88e6xxx_g1_modify(struct mv88e6xxx_chip *chip, int reg,
> 			       u16 mask, u16 val)
> {
> 	int addr = chip->info->global1_addr;
> 	int err;
> 	u16 v;
> 
> 	err = mv88e6xxx_read(chip, addr, reg, &v);
> 	if (err < 0)
> 		return err;
> 
> 	v = (v & ~mask) | val;
> 
> 	return mv88e6xxx_write(chip, addr, reg, v);
> }
> 
> Then, mv88e6185_g1_set_max_frame_size() becomes:
> 
> int mv88e6185_g1_set_max_frame_size(struct mv88e6xxx_chip *chip, int mtu)
> {
> 	u16 val = 0;
> 
> 	if (mtu + ETH_HLEN + ETH_FCS_LEN > 1518)
> 		val = MV88E6185_G1_CTL1_MAX_FRAME_1632;
> 
> 	return mv88e6xxx_g1_modify(chip, MV88E6XXX_G1_CTL1,
> 				   MV88E6185_G1_CTL1_MAX_FRAME_1632, val);
> }
> 
> The 6250 variant becomes similar.

+1, sounds good to have separate mv88e6185_g1_set_max_frame_size() and
mv88e6250_g1_set_max_frame_size() with a common implementation. It is a
lot less confusing than the two driving a bit named in the same way but
meaning different things.