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riscv-non-isa / riscv-server-platform

The RISC-V Server Platform specification defines a standardized set of hardware and sofware capabilities, that portable system software, such as operating systems and hypervisors, can rely on being present in a RISC-V server platform.
https://jira.riscv.org/browse/RVC-6
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Mandate IOMMU RIMT (ACPI) requirement #2

Open andreiw opened 5 months ago

andreiw commented 5 months ago

AFAICT Server SoC mandates IOMMU BRS has non-normative text about RIMT on systems supporting IOMMU

...need requirement in this spec to tie it together.

andreiw commented 3 months ago

Actually such a text could well be in the BRS document, but isn't (along with many other requirements that are implicit in the ACPI spec and dependent specs).

So do we really need the RIMT text (i.e. if you have an IOMMU, you will expose it via RIMT). Why would IOMMU get this treatment and something else (AIA) would not?

andreiw commented 3 months ago

The thought here is that ACPI doesn't actually require a RIMT for a RISC-V compliant IOMMU.

andreiw commented 3 months ago

The BRS does not really have normative text around the RIMT. A solution could be to make RIMT spec one of the BRS-I dependencies (and ensure RIMT has text that requires implementation if a compliant RISC-V IOMMU is present)