[M] Change in coreboot[master]: soc/intel/ehl: Add EHL MDIO operation

[Arthur Heymans (Code Review)]

Attention is currently required from: Mario Scheithauer, Angel Pons, Lean Sheng Tan, Werner Zeh.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/69383 )

Change subject: soc/intel/ehl: Add EHL MDIO operation
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Patch Set 7:

(2 comments)

File src/soc/intel/elkhartlake/mdio.c:

https://review.coreboot.org/c/coreboot/+/69383/comment/6b87c28c_44d5d4a3 
PS7, Line 68: == CB_ERR
nit: != CB_SUCCESS is preferable as it handles the other options in enum cb_err (even though they are not used in this case)

https://review.coreboot.org/c/coreboot/+/69383/comment/b4054528_b2cc3780 
PS7, Line 82: .read_resources		= noop_read_resources,
            : 	.set_resources		= noop_set_resources,
> > This should not be a PCI device, it's a mdio device. Are you sure that this will overwrite PCI device_operations?
>
> It is, you are even finding PCI BARs to get bases for MDIO ops.
>
> void mdio_dev_enable(struct device *dev)
> {
>    dev->ops = &mdio_dev_ops;
> }
>
> will override the PCI driver ops. See my suggestion in tsn_gbe.c file