Re: [PATCH net-next V2 2/2] net: axienet: Add support for 2500base-X only configuration.

[Andrew Lunn]

> +	/* AXI 1G/2.5G ethernet IP has following synthesis options:
> +	 * 1) SGMII/1000base-X only.
> +	 * 2) 2500base-X only.
> +	 * 3) Dynamically switching between (1) and (2), and is not
> +	 * implemented in driver.
> +	 */
> +
> +	if (axienet_ior(lp, XAE_ABILITY_OFFSET) & XAE_ABILITY_2_5G)

How can we tell if the synthesis allows 3)?

Don't we have a backwards compatibility issue here? Maybe there are
systems which have been synthesised with 3), but are currently limited
to 1) due to the driver. If you don't differentiate between 2 and 3,
such systems are going to swap to 2) and regress.

	Andrew