Re: [PATCH v2 3/5] cxl/acpi: Add platform flag for HPA address translation

[Dan Williams <dan.j.williams@intel.com>]

Robert Richter wrote:
> Adding an early check to detect platform specifics to (later) enable
> HPA address translation. The cxl_root structure is used to store that
> information.
> 
> Note: The platform check will be added later when enabling address
> translation.

It feels odd to have a flag at the root for this because the translation
is at the host-bridge level, right?

I was more thinking of a solution that does:

spa = cxld_hpa_to_spa(cxld);

...and then internal to that the code walks the port hierarchy from it's
host port to the host bridge. Then does something like

hb->hpa_to_spa(hb, hpa)

Where @hb is:

struct cxl_hb {
	struct cxl_port port;
	u64 (*hpa_to_spa)(struct cxl_hb *, u64);
}