Re: [edk2-devel] [Patch V2 0/2] Let AcpiTableDxe driver install Acpi table from Hob

["Benjamin Doron" <benjamin.doron00@gmail.com>]

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> 
> 
>> Hi all,
>> Would it be acceptable/feasible for AcpiTableDxe or AcpiPlatformDxe (in
>> MdeModulePkg) to use `EfiGetSystemConfigurationTable` to get the RSDP
>> and then install the tables? It's a solution that uses the regular
>> UefiLib, so it avoids platform-specific quirks (and as I see it, if RSDP
>> is in the configuration table, we probably always want those tables).
> 
> I'm sorry, I don't understand how this would help.

As I understand it, the issue is that this patchset changes MdeModulePkg to do platform-specific parsing.

Perhaps it would be an acceptable solution for platforms to retrieve the tables, then add
RSDP/them to the configuration table to be installed by AcpiTableDxe/AcpiPlatformDxe.
This allows MdeModulePkg to abstract away the parsing, only installing tables
available to it.
(Currently, UefiPayloadPkg's BlSupportDxe retrieves the data from a HOB and calls
`gBS->InstallConfigurationTable` with the address of RSDP).

I understand that this may not work for OVMF if tables are located differently in memory.

> 
> 
>> Regarding UefiPayloadPkg: AcpiTableDxe is currently compiled (listed in
>> DSC) but not added to a FV (not listed in FDF). So, how has this been
>> tested?
> 
> I assume through an out-of-tree platform. Many such core modules exist
> in edk2 that are not consumed by any of the virtual platforms in the
> edk2 repo itself (EmulatorPkg, ArmVirtPkg, OvmfPkg).

This makes sense, but AcpiTableDxe must be added to UefiPayloadPkg's FDF
if patch 2/2 is merged. Otherwise, ACPI tables will not be advertised.

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