[PATCH RESEND2 net-next 4/8] phy: qcom-sgmii-eth: remove .set_speed() implementation

[Vladimir Oltean]

On Thu, Feb 26, 2026 at 11:09:37PM +0000, Russell King (Oracle) wrote:
> Now that the qcom-ethqos driver has migrated to use phy_set_mode_ext()
> rather than phy_set_speed() to configure the SerDes, the support for
> phy_set_speed() is now obsolete. Remove support for this method.
> 
> Using the MAC speed for the SerDes is never correct due to the PCS
> encoding. For SGMII and 2500BASE-X, the PCS uses 8B10B encoding, and
> so:
> 
>   MAC rate * PCS output bits / PCS input bits = SerDes rate
>    1000M   *       10        /       8        = 1250M
>    2500M   *       10        /       8        = 3125M
> 
> Tested-by: Mohd Ayaan Anwar <mohd.anwar at oss.qualcomm.com>
> Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean at nxp.com>