[PATCH v2 2/2] phy: add driver for MediaTek XFI T-PHY

[AngeloGioacchino Del Regno]

Il 05/02/24 18:29, Daniel Golle ha scritto:
> Add driver for MediaTek's XFI T-PHY which can be found in the MT7988
> SoC. The XFI T-PHY is a 10 Gigabit/s Ethernet SerDes PHY with muxes on
> the internal side to be used with either USXGMII PCS or LynxI PCS,
> depending on the selected PHY interface mode.
> 
> The PHY can operates only in PHY_MODE_ETHERNET, the submode is one of
> PHY_INTERFACE_MODE_* corresponding to the supported modes:
> 
>   * USXGMII                 \
>   * 10GBase-R                }- USXGMII PCS - XGDM  \
>   * 5GBase-R                /                        \
>                                                       }- Ethernet MAC
>   * 2500Base-X              \                        /
>   * 1000Base-X               }- LynxI PCS - GDM     /
>   * Cisco SGMII (MAC side)  /
> 
> In order to work-around a performance issue present on the first of
> two XFI T-PHYs present in MT7988, special tuning is applied which can be
> selected by adding the 'mediatek,usxgmii-performance-errata' property to
> the device tree node.
> 
> There is no documentation for most registers used for the
> analog/tuning part, however, most of the registers have been partially
> reverse-engineered from MediaTek's SDK implementation (an opaque
> sequence of 32-bit register writes) and descriptions for all relevant
> digital registers and bits such as resets and muxes have been supplied
> by MediaTek.
> 
> Signed-off-by: Daniel Golle <daniel at makrotopia.org>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>