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charset=UTF-8 Content-Transfer-Encoding: 7bit On 03/11/2026 03:57, Cui Chao wrote: > > On 11/2/2026 6:00 PM, Krzysztof Kozlowski wrote: >> On 02/11/2026 10:51, Cui Chao wrote: >>> Add a new optional boolean property 'linux,pci-domain-reuse' for PCI >>> host bridges. >>> >>> By default, the 'linux,pci-domain' property must be unique across all >>> host bridges. This property allows a host bridge to explicitly opt-out >>> of this uniqueness check, permitting multiple host bridges to reuse the >>> same software domain number. >> Why isn't this deducible from the compatibles? > Hi Krzysztof, > > Thanks. > > The compatible cannot express this. "pci-host-ecam-generic" only You have vendor specific compatibles, no? > describes how configuration space is accessed; it does not describe > whether two host bridge instances may share one Linux PCI domain. > > The same compatible is used on systems where every host bridge must > have a unique domain and on this system where two RCs intentionally > share a domain with disjoint bus ranges and resource windows. > Comparing the compatible strings of the nodes therefore cannot > distinguish our case. OK, so let's look at your DTS - where is it posted for upstream? > > Adding a vendor-specific compatible only to trigger this Linux policy > would not describe a different hardware programming model either. > What actually makes reuse valid is the platform-level relationship: > the bus ranges and resource windows are disjoint. > > If you prefer to avoid a new property, I can rework this to derive or > validate reuse from the non-overlapping bus-range and resource layout > instead. Would that be the preferred direction? > This one is clear paste of LLM output to a message. Best regards, Krzysztof