AcpiPlatform: use GUIDed HOBs for VMM-provided ACPI tables#77
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Instead of having a dedicated config blob type, PCD pair, and DXE installer function for each ACPI table the VMM can provide (MADT, SRAT, SLIT, PPTT, HMAT, MCFG, SSDT, IORT, ASPT), use a single generic path: PEI validates the embedded ACPI header and emits a GUIDed HOB; DXE iterates the HOB list and installs each table, suppressing the matching FV-resident default. The MADT installer is kept for the IGVM/TDX path, which needs to post-process the table (MP wakeup mailbox), but is now a no-op when the PCDs are unset. The IGVM SRAT is emitted as a HOB. The NFIT installer is unrelated (synthesized from BIOS device MMIO) and is unchanged. PciHostBridgeLib and PciSegmentInfoLib now read MCFG directly from the HOB list, removing PcdMcfgPtr/PcdMcfgSize.
| EFI_ACPI_DESCRIPTION_HEADER *madtHdr = (EFI_ACPI_DESCRIPTION_HEADER*)madtStructure->Madt; | ||
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| if (madtStructure->Header.Length < (sizeof(UEFI_CONFIG_HEADER) + sizeof(EFI_ACPI_DESCRIPTION_HEADER)) || | ||
| madtHdr->Signature != EFI_ACPI_6_2_MULTIPLE_APIC_DESCRIPTION_TABLE_SIGNATURE || |
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Yes. I think that's OK, since the validation here is not very interesting and it's really just helping diagnose VMM bugs... and poorly since most of the time you just get a random triple fault or reset if UEFI gives up.
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This change brings support for multi-instance tables provided by the VMM (e.g. SSDT); nice! Perhaps we need to think about how to make a FV-provided SSDT can not be overridden by a VMM-provided extension. That can probably be deferred to a future PR |
| #endif | ||
| case UefiConfigMcfg: | ||
| case UefiConfigSsdt: | ||
| case UefiConfigIort: |
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want to alphabetize?
In this model, we may not need separate types for all of these; just passing multiple instances of UefiConfigAcpiTable might do...
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Right, we don't need these anymore. I think we should update the VMMs to just use the single generic blob and then we can reclaim all these other enum values.
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Instead of having a dedicated config blob type, PCD pair, and DXE installer function for each ACPI table the VMM can provide (MADT, SRAT, SLIT, PPTT, HMAT, MCFG, SSDT, IORT, ASPT), use a single generic path: PEI validates the embedded ACPI header and emits a GUIDed HOB; DXE iterates the HOB list and installs each table, suppressing the matching FV-resident default.
The MADT installer is kept for the IGVM/TDX path, which needs to post-process the table (MP wakeup mailbox), but is now a no-op when the PCDs are unset. The IGVM SRAT is emitted as a HOB. The NFIT installer is unrelated (synthesized from BIOS device MMIO) and is unchanged. PciHostBridgeLib and PciSegmentInfoLib now read MCFG directly from the HOB list, removing PcdMcfgPtr/PcdMcfgSize.