Re: [RFC PATCH 2/4] PCI/CXL: Populate and insert/remove pdev->coh_resource[]

[Ankit Agrawal]

>> +
>> +             *res = DEFINE_RES_NAMED_DESC(config->hpa_range.start,
>> +                                          range_len(&config->hpa_range),
>> +                                          "CXL coherent memory",
>> +                                          IORESOURCE_MEM, IORES_DESC_NONE);
>> +
>
> On platforms using Normalized Addressing the Endpoint decoders contain DPA ranges. This 
> patch will then record DPA ranges as a result. Translating this requires call to prm_cxl_dpa_spa() ?
> The challenge is the PRM in drivers/cxl/core/atl.c may not be initialized this early.
>

Yeah, good point. On the platforms that I used, the HDM are precommitted
and have HPA. But I agree, the snapshot must not silently record a DPA.

Is there an existing way to tell at this point that the endpoint decoder is
DPA-based? If yes, I intend to fail close with coh_resource[] left unpopulated
Or would you prefer populating lazily until translations are available?


>> +             conflict = insert_resource_conflict(&iomem_resource, res);
>> +             if (conflict) {
>> +                     pci_warn(pdev,