Requirement:
In current working model, to change the default setting in HII VarStore, VFR
source files have to be modified. There is no platform override way. This
requirement is to move such configure setting to platform DSC, and provide the
centralized setting in platform DSC. The idea is to use DynamicHii PCD setting
in Platform DSC file as the EFI Variable and HII EFI VarStore default setting,
because DynamicHii PCD has specified the relationship between PCD and EFI
variable.
Dependency:
1) [RFC] StructuredPcd Value assignment in DEC/DSC
2) [RFC] VFR BIT and UNION extension in Varstore structure
Proposal with below 4 changes:
1. Extend PcdsDynamicHii section in DSC file with DefaultStoreName.
DefaultStore is UEFI HII Default ID. New [DefaultStores] section is introduced
to list the map between DefaultStore name and DefaultId value. PcdsDynamicHii
can specify the default settings for the different DefaultStore. If
DefaultStoreName is not specified, the setting will target for Standard
default. Default Store setting is specified for HII EFI VarStore. They will not
be built into PCD data base except for Standard default.
Example in DSC file that PcdSetupConOutBuffer value will be used as
SetupConsoleConfig variable and HII EFI varstore:
[DefaultStores]
0 | Standard # UEFI Standard default
1 | Manufacturing # UEFI Manufacturing default
[PcdsDynamicHii.common.DEFAULT]
[PcdsDynamicHii.common.DEFAULT.Standard]
gEfiMdeModulePkgTokenSpaceGuid.PcdSetupConOutBuffer|L"SetupConsoleConfig"|gEfiNt32PkgTokenSpaceGuid|0x0|{0xFF}|NV,BS
gEfiMdeModulePkgTokenSpaceGuid.PcdSetupConOutBuffer.Column|80
gEfiMdeModulePkgTokenSpaceGuid.PcdSetupConOutBuffer.Row|25
2. Introduce new PCD VOID* PcdNvStoreDefaultValueBuffer to store the
default setting in MdeModulePkg
a. PcdNvStoreDefaultValueBuffer value is auto generated by build.
BaseTools will collect PCD default settings in all PcdsDynamicHii section, and
save them as the normal variable storage format, then assign it to
PcdNvStoreDefaultValueBuffer.
b. PcdNvStoreDefaultValueBuffer value will include the default setting for
each SkuId and DefaultId. The default setting for SkuId 0 and Defaultd 0 is
stored as the whole copy. Other default setting are stored as the delta
compared to the full setting. This way can save its buffer size.
c. PcdNvStoreDefaultValueBuffer must be configured as DynamicExVPD in
platform DSC, and be placed into VPD region. Then, it can be kept as the read
only data in BIOS image.
3. Introduce new PCD UINT16 PcdSetNvStoreDefaultId to enable the default
variable setting in MdeModulePkg
a. PcdSetNvStoreDefaultId is configured as DynamicDefault. Its value is
the default store ID value. The default value is zero as Standard default.
b. Once PcdSetNvStoreDefaultId is set, PcdPeim will read the matched
default setting from PcdNvStoreDefaultValueBuffer, and build the variable hob
to store the default EFI variable settings with the normal variable storage
format (gEfiVariableGuid).
c. PlatformPei must SetSkuId() first, then set PcdSetNvStoreDefaultId.
Otherwise, the default variable setting may not be matched.
d. If the matched VariableHob is found, Variable RuntimeDxe driver will
consume VariableHob and write them into NV region. This logic is ready now. The
enhancement is to support the variable hob with gEfiVariableGuid even if
AuthVariable is used.
4. Enhance HiiDataBaseDxe to consume PcdNvStoreDefaultValueBuffer to get
the default setting and patch IFR default setting in the installed HII packages.
a. The patched HII package lists will be applied when Reset to default is
trigged in UI page after ReadyToBoot
b. Report System Configuration table with the patched HII package lists at
ReadyToBoot
c. ExportPackageLists() API reports the patched HII package lists based
on current SkuId
Thanks
Liming
_______________________________________________
edk2-devel mailing list
edk2-devel@lists.01.org
https://lists.01.org/mailman/listinfo/edk2-devel
