Date:   Sun, 19 Mar 2023 11:06:06 +0100
From:   Marek =?UTF-8?B?QmVow7pu?= <marek.behun@nic.cz>
To:     Klaus Kudielka <klaus.kudielka@gmail.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@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>,
        Richard Cochran <richardcochran@gmail.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently
 non-existing phys during probing
Message-ID: <20230319110606.23e30050@thinkpad>
In-Reply-To: <20230315163846.3114-5-klaus.kudielka@gmail.com>
References: <20230315163846.3114-1-klaus.kudielka@gmail.com>
        <20230315163846.3114-5-klaus.kudielka@gmail.com>
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On Wed, 15 Mar 2023 17:38:46 +0100
Klaus Kudielka <klaus.kudielka@gmail.com> wrote:

> To avoid excessive mdio bus transactions during probing, mask all phy
> addresses that do not exist (there is a 1:1 mapping between switch port
> number and phy address).
> 
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---
> 
> Notes:
>     v2: Patch is new
> 
>  drivers/net/dsa/mv88e6xxx/chip.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
> index 29b0f3bb1c..c52798d9ce 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -3797,6 +3797,7 @@ static int mv88e6xxx_mdio_register(struct mv88e6xxx_chip *chip,
>  	bus->read_c45 = mv88e6xxx_mdio_read_c45;
>  	bus->write_c45 = mv88e6xxx_mdio_write_c45;
>  	bus->parent = chip->dev;
> +	bus->phy_mask = GENMASK(31, mv88e6xxx_num_ports(chip));

shouldnt this be
  GENMASK(31, mv88e6xxx_num_ports(chip) + chip->info->phy_base_addr) |
  GENMASK(chip->info->phy_base_addr, 0)
?
Or alternatively
  ~GENMASK(chip->info->phy_base_addr + mv88e6xxx_num_ports(chip),
           chip->info->phy_base_addr)

Marek