Hi all! I'm playing with a Colorlight A5-75B board with the aim to get some RGMII running en the end - but before that I'm porting old code I have from `nmigen`, specifically a PLL helper I found sometime long ago. The issue I'm hitting is that something has changed from `nmigen` to `amaranth`, as when I connect the input clock `i_CLKI` of the PLL to a `ClockDomain` I get the following error, does anyone know what is the issue? 

```
  File "/home/emifre/Git/colorlight-5a-75b-ethernet/gateware/ecp5pll.py", line 235, in elaborate
    m.submodules.pll = Instance("EHXPLLL",
                       ~~~~~~~~^^^^^^^^^^^
        # Clock in.
        ^^^^^^^^^^^
    ...<79 lines>...
        a_MFG_GMCREF_SEL="2",
        ^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/usr/lib/python3.13/site-packages/amaranth/hdl/_ir.py", line 350, in __init__
    arg = _ast.Value.cast(arg)
  File "/usr/lib/python3.13/site-packages/amaranth/hdl/_ast.py", line 577, in cast
    raise TypeError(f"Object {obj!r} cannot be converted to an Amaranth value")
TypeError: Object flipped(<Pin: Pin.Signature(1, dir='i'), path=('clk25_0',), name='clk25_0', i=(sig clk25_0__i)>) cannot be converted to an Amaranth value
```

The specific code line is here: https://github.com/korken89/colorlight-5a-75b-ethernet/blob/main/gateware/ecp5pll.py#L237

I've also compared with this PLL abstraction https://github.com/msvisser/riscv-tilelink/blob/main/ecp5pll.py which seems to do the same thing I do - so I'm a bit lost 😅