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Date:   Fri, 16 Dec 2022 16:54:16 +0000
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Sean Anderson <sean.anderson@seco.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>, netdev@vger.kernel.org,
        Paolo Abeni <pabeni@redhat.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        linux-kernel@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
        Tim Harvey <tharvey@gateworks.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH net-next v4 0/4] phy: aquantia: Determine rate adaptation
 support from registers
Message-ID: <Y5yiuJYfqQlS0DX8@shell.armlinux.org.uk>
References: <20221216164851.2932043-1-sean.anderson@seco.com>
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In-Reply-To: <20221216164851.2932043-1-sean.anderson@seco.com>
Sender: Russell King (Oracle) <linux@armlinux.org.uk>
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Hi Sean,

Please note net-next is currently closed due to the merge window, so
please don't send patches for it. However, feel free to send RFC
patches for net-next so that reviews can still happen.

Thanks!

On Fri, Dec 16, 2022 at 11:48:47AM -0500, Sean Anderson wrote:
> This attempts to address the problems first reported in [1]. Tim has an
> Aquantia phy where the firmware is set up to use "5G XFI" (underclocked
> 10GBASE-R) when rate adapting lower speeds. This results in us
> advertising that we support lower speeds and then failing to bring the
> link up. To avoid this, determine whether to enable rate adaptation
> based on what's programmed by the firmware. This is "the worst choice"
> [2], but we can't really do better until we have more insight into
> what the firmware is doing. At the very least, we can prevent bad
> firmware from causing us to advertise the wrong modes.
> 
> Past submissions may be found at [3, 4].
> 
> [1] https://lore.kernel.org/netdev/CAJ+vNU3zeNqiGhjTKE8jRjDYR0D7f=iqPLB8phNyA2CWixy7JA@mail.gmail.com/
> [2] https://lore.kernel.org/netdev/20221118171643.vu6uxbnmog4sna65@skbuf/
> [3] https://lore.kernel.org/netdev/20221114210740.3332937-1-sean.anderson@seco.com/
> [4] https://lore.kernel.org/netdev/20221128195409.100873-1-sean.anderson@seco.com/
> 
> Changes in v4:
> - Reorganize MDIO defines
> - Fix kerneldoc using - instead of : for parameters
> 
> Changes in v3:
> - Update speed register bits
> - Fix incorrect bits for PMA/PMD speed
> 
> Changes in v2:
> - Move/rename phylink_interface_max_speed
> - Rework to just validate things instead of modifying registers
> 
> Sean Anderson (4):
>   net: phy: Move/rename phylink_interface_max_speed
>   phy: mdio: Reorganize defines
>   net: mdio: Update speed register bits
>   phy: aquantia: Determine rate adaptation support from registers
> 
>  drivers/net/phy/aquantia_main.c | 160 ++++++++++++++++++++++++++++++--
>  drivers/net/phy/phy-core.c      |  70 ++++++++++++++
>  drivers/net/phy/phylink.c       |  75 +--------------
>  include/linux/phy.h             |   1 +
>  include/uapi/linux/mdio.h       | 109 ++++++++++++++--------
>  5 files changed, 299 insertions(+), 116 deletions(-)
> 
> -- 
> 2.35.1.1320.gc452695387.dirty
> 
> 

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