> On Aug 13, 2021, at 4:45 AM, Bob Feng <bob.c.feng@intel.com> wrote:
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3562
> 
> Create a new build option to enable vfrcompile to generate Json
> format EFI variable information file and read it to generate 
> the EFI variable default value binary file.
> 
> Signed-off-by: Bob Feng <bob.c.feng@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Yuwei Chen <yuwei.chen@intel.com>
> ---
> BaseTools/Source/Python/AutoGen/DataPipe.py   |   2 +
> .../Source/Python/AutoGen/GenDefaultVar.py    | 498 ++++++++++++++++++
> .../Source/Python/AutoGen/ModuleAutoGen.py    |   9 +
> .../Python/AutoGen/ModuleAutoGenHelper.py     |   4 +
> BaseTools/Source/Python/Common/GlobalData.py  |   5 +
> BaseTools/Source/Python/build/build.py        |  18 +
> BaseTools/Source/Python/build/buildoptions.py |   1 +
> 7 files changed, 537 insertions(+)
> create mode 100644 BaseTools/Source/Python/AutoGen/GenDefaultVar.py
> 
> diff --git a/BaseTools/Source/Python/AutoGen/DataPipe.py b/BaseTools/Source/Python/AutoGen/DataPipe.py
> index 86ac2b928d9c..fa0c36b98f21 100755
> --- a/BaseTools/Source/Python/AutoGen/DataPipe.py
> +++ b/BaseTools/Source/Python/AutoGen/DataPipe.py
> @@ -165,5 +165,7 @@ class MemoryDataPipe(DataPipe):
>         self.DataContainer = {"BinCacheSource":GlobalData.gBinCacheSource}
> 
>         self.DataContainer = {"BinCacheDest":GlobalData.gBinCacheDest}
> 
>         self.DataContainer = {"EnableGenfdsMultiThread":GlobalData.gEnableGenfdsMultiThread}
> +
> +        self.DataContainer = {"GenDefaultVarBin": GlobalData.gGenDefaultVarBin}
> diff --git a/BaseTools/Source/Python/AutoGen/GenDefaultVar.py b/BaseTools/Source/Python/AutoGen/GenDefaultVar.py
> new file mode 100644
> index 000000000000..b82cce18ed26
> --- /dev/null
> +++ b/BaseTools/Source/Python/AutoGen/GenDefaultVar.py
> @@ -0,0 +1,498 @@
> +import json
> +from ctypes import *
> +import re
> +import copy
> +from struct import unpack
> +import os
> +
> +class GUID(Structure):

We should use (LittleEndianStructure) vs. (Structure). Structure is the endian of the Host, and EFI is little endian. Same comment for all the ctype structs. LittleEndianStructure is like using < with struct.pack()/struct.unpack(). 

> +    _fields_ = [
> +        ('Guid1',            c_uint32),
> +        ('Guid2',            c_uint16),
> +        ('Guid3',            c_uint16),
> +        ('Guid4',            ARRAY(c_uint8, 8)),
> +    ]
> +

I think it would be better to use the same field names as the EFI C structures. 

typedef struct {
  UINT32  Data1;
  UINT16  Data2;
  UINT16  Data3;
  UINT8   Data4[8];
} GUID


Longer term I think the BaseBools should have a GUID class that can be shared that abstracts things GUIDs. It should store GUIDs as Python uuid.UUID() or at least in the common string form, and have useful operations. 

I’ve got an example GUID class in my gdb patch set, but it also loads the GUID database and deals with C name, C GUID structure init form, and strings. But it feels like we could pull out a common lower level GUID class out of that. 

> +    def from_list(self, listformat):
> +        self.Guid1 = listformat[0]
> +        self.Guid2 = listformat[1]
> +        self.Guid3 = listformat[2]
> +        for i in range(8):
> +            self.Guid4[i] = listformat[i+3]
> +
> +    def __cmp__(self, otherguid):
> +        if isinstance(otherguid, GUID):
> +            return 1
> +        rt = False
> +        if self.Guid1 == otherguid.Guid1 and self.Guid2 == otherguid.Guid2 and self.Guid3 == otherguid.Guid3:
> +            rt = True
> +            for i in range(8):
> +                rt = rt & (self.Guid4[i] == otherguid.Guid4[i])
> +        return rt
> +
> +
> +class TIME(Structure):
> +    _fields_ = [
> +        ('Year',             c_uint16),
> +        ('Month',            c_uint8),
> +        ('Day',              c_uint8),
> +        ('Hour',             c_uint8),
> +        ('Minute',           c_uint8),
> +        ('Second',           c_uint8),
> +        ('Pad1',             c_uint8),
> +        ('Nanosecond',       c_uint32),
> +        ('TimeZone',         c_uint16),
> +        ('Daylight',         c_uint8),
> +        ('Pad2',             c_uint8),
> +    ]
> +    def __init__(self):
> +        self.Year = 0x0
> +        self.Month = 0x0
> +        self.Day = 0x0
> +        self.Hour = 0x0
> +        self.Minute = 0x0
> +        self.Second = 0x0
> +        self.Pad1 = 0x0
> +        self.Nanosecond = 0x0
> +        self.TimeZone = 0x0
> +        self.Daylight = 0x0
> +        self.Pad2 = 0x0
> +
> +
> +EFI_VARIABLE_GUID = [0xddcf3616, 0x3275, 0x4164,
> +                     0x98, 0xb6, 0xfe, 0x85, 0x70, 0x7f, 0xfe, 0x7d]
> +EFI_AUTHENTICATED_VARIABLE_GUID = [
> +    0xaaf32c78, 0x947b, 0x439a, 0xa1, 0x80, 0x2e, 0x14, 0x4e, 0xc3, 0x77, 0x92]
> +
> +AuthVarGuid = GUID()
> +AuthVarGuid.from_list(EFI_AUTHENTICATED_VARIABLE_GUID)
> +VarGuid = GUID()
> +VarGuid.from_list(EFI_VARIABLE_GUID)
> +
> +# Variable Store Header Format.
> +VARIABLE_STORE_FORMATTED = 0x5a
> +# Variable Store Header State.
> +VARIABLE_STORE_HEALTHY = 0xfe
> +
> +
> +class VARIABLE_STORE_HEADER(Structure):
> +    _fields_ = [
> +        ('Signature',                GUID),
> +        ('Size',                     c_uint32),
> +        ('Format',                   c_uint8),
> +        ('State',                    c_uint8),
> +        ('Reserved',                 c_uint16),
> +        ('Reserved1',                c_uint32),
> +    ]
> +
> +
> +# Variable data start flag.
> +VARIABLE_DATA = 0x55AA
> +
> +# Variable State flags.
> +VAR_IN_DELETED_TRANSITION = 0xfe
> +VAR_DELETED = 0xfd
> +VAR_HEADER_VALID_ONLY = 0x7f
> +VAR_ADDED = 0x3f
> +
> +
> +class VARIABLE_HEADER(Structure):
> +    _fields_ = [
> +        ('StartId',                  c_uint16),
> +        ('State',                    c_uint8),
> +        ('Reserved',                 c_uint8),
> +        ('Attributes',               c_uint32),
> +        ('NameSize',                 c_uint32),
> +        ('DataSize',                 c_uint32),
> +        ('VendorGuid',               GUID),
> +    ]
> +
> +
> +class AUTHENTICATED_VARIABLE_HEADER(Structure):
> +    _fields_ = [
> +        ('StartId',                  c_uint16),
> +        ('State',                    c_uint8),
> +        ('Reserved',                 c_uint8),
> +        ('Attributes',               c_uint32),
> +        ('MonotonicCount',           c_uint64),
> +        ('TimeStamp',                TIME),
> +        ('PubKeyIndex',              c_uint32),
> +        ('NameSize',                 c_uint32),
> +        ('DataSize',                 c_uint32),
> +        ('VendorGuid',               GUID),
> +    ]
> +    _pack_ = 1
> +
> +
> +# Alignment of Variable Data Header in Variable Store region.
> +HEADER_ALIGNMENT = 4
> +
> +
> +class DEFAULT_INFO(Structure):
> +    _fields_ = [
> +        ('DefaultId',                c_uint16),
> +        ('BoardId',                  c_uint16),
> +    ]
> +
> +
> +class DEFAULT_DATA(Structure):
> +    _fields_ = [
> +        ('HeaderSize',               c_uint16),
> +        ('DefaultInfo',              DEFAULT_INFO),
> +    ]
> +
> +class DELTA_DATA(Structure):
> +    _fields_ = [
> +        ('Offset', c_uint16),
> +        ('Value', c_uint8),
> +    ]
> +    _pack_ = 1
> +
> +array_re = re.compile(
> +    "(?P<mType>[a-z_A-Z][a-z_A-Z0-9]*)\[(?P<mSize>[1-9][0-9]*)\]")
> +
> +
> +class VarField():
> +    def __init__(self):
> +        self.Offset = 0
> +        self.Value = 0
> +        self.Size = 0
> +
> +    @property
> +    def Type(self):
> +        if self.Size == 1:
> +            return "UINT8"
> +        if self.Size == 2:
> +            return "UINT16"
> +        if self.Size == 4:
> +            return "UINT32"
> +        if self.Size == 8:
> +            return "UINT64"
> +
> +        return "UINT8"
> +
> +
> +BASIC_TYPE = {
> +    "BOOLEAN": 1,
> +    "UINT8": 1,
> +    "UINT16": 2,
> +    "UINT32": 4,
> +    "UINT64": 8
> +}

This might be more of a phase 2….

I think you made a lot of extra work by inventing your own type system. You should just convert to ctype as fast as you can. 

BASIC_TYPE = {
    "BOOLEAN": c_uint8,
    "UINT8": c_uint8,
    "UINT16": c_uint16,
    "UINT32": c_uint32,
    "UINT64": c_uint64
}

Then you can just sizeof() to get the size

FYI I wrote this ctype dumper in case it is useful debugging this code.  It picks off EFI_GUID so it can print it as a proper UUID using the GUID class I mentioned above, so basically a nicer print option. 

def ctype_to_str(ctype, indent='', hide_list=[]):
    '''
    Given a ctype object print out as a string by walking the _fields_
    in the cstring Class
     '''
    result = ''
    for field in ctype._fields_:
        attr = getattr(ctype, field[0])
        tname = type(attr).__name__
        if field[0] in hide_list:
            continue

        result += indent + f'{field[0]} = '
        if tname == 'EFI_GUID':
            result += GuidNames.to_name(GuidNames.to_uuid(attr)) + '\n'
        elif issubclass(type(attr), Structure):
            result += f'{tname}\n' + \
                ctype_to_str(attr, indent + '  ', hide_list)
        elif isinstance(attr, int):
            result += f'0x{attr:x}\n'
        else:
            result += f'{attr}\n'

    return result

Thanks,

Andrew Fish

> +class CStruct():
> +
> +
> +    def __init__(self, typedefs):
> +        self.TypeDefs = typedefs
> +        self.TypeStack = copy.deepcopy(typedefs)
> +        self.finalDefs = {}
> +
> +    def CalStuctSize(self, sType):
> +        rt = 0
> +        if sType in BASIC_TYPE:
> +            return BASIC_TYPE[sType]
> +
> +        ma = array_re.match(sType)
> +        if ma:
> +            mType = ma.group('mType')
> +            mSize = ma.group('mSize')
> +            rt += int(mSize) * self.CalStuctSize(mType)
> +        else:
> +            for subType in self.TypeDefs[sType]:
> +                rt += self.CalStuctSize(subType['Type'])
> +
> +        return rt
> +
> +    def expend(self, fielditem):
> +        fieldname = fielditem['Name']
> +        fieldType = fielditem['Type']
> +        fieldOffset = fielditem['Offset']
> +
> +        ma = array_re.match(fieldType)
> +        if ma:
> +            mType = ma.group('mType')
> +            mSize = ma.group('mSize')
> +            return [{"Name": "%s[%d]" % (fieldname, i), "Type": mType, "Offset": (fieldOffset + i*self.CalStuctSize(mType))} for i in range(int(mSize))]
> +        else:
> +            return [{"Name": "%s.%s" % (fieldname, item['Name']), "Type":item['Type'], "Offset": (fieldOffset + item['Offset'])} for item in self.TypeDefs[fielditem['Type']]]
> +
> +    def ExpandTypes(self):
> +        if not self.finalDefs:
> +            for datatype in self.TypeStack:
> +                result = []
> +                mTypeStack = self.TypeStack[datatype]
> +                while len(mTypeStack) > 0:
> +                    item = mTypeStack.pop()
> +                    if item['Type'] in self.BASIC_TYPE:
> +                        result.append(item)
> +                    elif item['Type'] == '(null)':
> +                        continue
> +                    else:
> +                        for expand_item in self.expend(item):
> +                            mTypeStack.append(expand_item)
> +                self.finalDefs[datatype] = result
> +            self.finalDefs
> +        return self.finalDefs
> +
> +def Get_Occupied_Size(FileLength, alignment):
> +    if FileLength % alignment == 0:
> +        return FileLength
> +    return FileLength + (alignment-(FileLength % alignment))
> +
> +def Occupied_Size(buffer, alignment):
> +    FileLength = len(buffer)
> +    if FileLength % alignment != 0:
> +        buffer += b'\0' * (alignment-(FileLength % alignment))
> +    return buffer
> +
> +def PackStruct(cStruct):
> +    length = sizeof(cStruct)
> +    p = cast(pointer(cStruct), POINTER(c_char * length))
> +    return p.contents.raw
> +
> +def calculate_delta(default, theother):
> +
> +    if len(default) - len(theother) != 0:
> +        return []
> +
> +    data_delta = []
> +    for i in range(len(default)):
> +        if default[i] != theother[i]:
> +            data_delta.append([i, theother[i]])
> +    return data_delta
> +
> +class Variable():
> +    def __init__(self):
> +        self.mAlign = 1
> +        self.mTotalSize = 1
> +        self.mValue = {}  # {defaultstore: value}
> +        self.mBin = {}
> +        self.fields = {}  # {defaultstore: fileds}
> +        self.delta = {}
> +        self.attributes = 0
> +        self.mType = ''
> +        self.guid = ''
> +        self.mName = ''
> +        self.cDefs = None
> +
> +    @property
> +    def GuidArray(self):
> +
> +        guid_array = []
> +        guid = self.guid.strip().strip("{").strip("}")
> +        for item in guid.split(","):
> +            field = item.strip().strip("{").strip("}")
> +            guid_array.append(int(field,16))
> +        return guid_array
> +
> +    def update_delta_offset(self,base):
> +        for default_id in self.delta:
> +            for delta_list in self.delta[default_id]:
> +                delta_list[0] += base
> +
> +    def pack(self):
> +
> +        for defaultid in self.mValue:
> +            var_value = self.mValue[defaultid]
> +            auth_var = AUTHENTICATED_VARIABLE_HEADER()
> +            auth_var.StartId = VARIABLE_DATA
> +            auth_var.State = VAR_ADDED
> +            auth_var.Reserved = 0x00
> +            auth_var.Attributes = 0x00000007
> +            auth_var.MonotonicCount = 0x0
> +            auth_var.TimeStamp = TIME()
> +            auth_var.PubKeyIndex = 0x0
> +            var_name_buffer = self.mName.encode('utf-16le') + b'\0\0'
> +            auth_var.NameSize = len(var_name_buffer)
> +            auth_var.DataSize = len(var_value)
> +            vendor_guid = GUID()
> +            vendor_guid.from_list(self.GuidArray)
> +            auth_var.VendorGuid = vendor_guid
> +
> +            self.mBin[defaultid] = PackStruct(auth_var) + Occupied_Size(var_name_buffer + var_value, 4)
> +
> +    def TypeCheck(self,data_type, data_size):
> +        if BASIC_TYPE[data_type] == data_size:
> +            return True
> +        return False
> +
> +    def ValueToBytes(self,data_type,data_value,data_size):
> +
> +        rt = b''
> +        if not self.TypeCheck(data_type, data_size):
> +            print(data_type,data_value,data_size)
> +
> +        if data_type == "BOOLEAN" or data_type == 'UINT8':
> +            p = cast(pointer(c_uint8(int(data_value,16))), POINTER(c_char * 1))
> +            rt = p.contents.raw
> +        elif data_type == 'UINT16':
> +            p = cast(pointer(c_uint16(int(data_value,16))), POINTER(c_char * 2))
> +            rt = p.contents.raw
> +        elif data_type == 'UINT32':
> +            p = cast(pointer(c_uint32(int(data_value,16))), POINTER(c_char * 4))
> +            rt = p.contents.raw
> +        elif data_type == 'UINT64':
> +            p = cast(pointer(c_uint64(int(data_value,16))), POINTER(c_char * 8))
> +            rt = p.contents.raw
> +
> +        return rt
> +
> +    def serial(self):
> +        for defaultstore in self.fields:
> +            vValue = b''
> +            vfields = {vf.Offset: vf for vf in self.fields[defaultstore]}
> +            i = 0
> +            while i < self.mTotalSize:
> +                if i in vfields:
> +                    vfield = vfields[i]
> +                    vValue += self.ValueToBytes(vfield.Type, vfield.Value,vfield.Size)
> +                    i += vfield.Size
> +                else:
> +                    vValue += self.ValueToBytes('UINT8','0x00',1)
> +                    i += 1
> +
> +            self.mValue[defaultstore] = vValue
> +        standard_default = self.mValue[0]
> +
> +        for defaultid in self.mValue:
> +            if defaultid == 0:
> +                continue
> +            others_default = self.mValue[defaultid]
> +
> +            self.delta.setdefault(defaultid, []).extend(calculate_delta(
> +                standard_default, others_default))
> +
> +class DefaultVariableGenerator():
> +    def __init__(self):
> +        self.NvVarInfo = []
> +
> +    def LoadNvVariableInfo(self, VarInfoFilelist):
> +
> +        VarDataDict = {}
> +        DataStruct = {}
> +        VarDefine = {}
> +        VarAttributes = {}
> +        for VarInfoFile in VarInfoFilelist:
> +            with open(VarInfoFile.strip(), "r") as fd:
> +                data = json.load(fd)
> +
> +            DataStruct.update(data.get("DataStruct", {}))
> +            Data = data.get("Data")
> +            VarDefine.update(data.get("VarDefine"))
> +            VarAttributes.update(data.get("DataStructAttribute"))
> +
> +            for vardata in Data:
> +                if vardata['VendorGuid'] == 'NA':
> +                    continue
> +                VarDataDict.setdefault(
> +                    (vardata['VendorGuid'], vardata["VarName"]), []).append(vardata)
> +
> +        cStructDefs = CStruct(DataStruct)
> +        for guid, varname in VarDataDict:
> +            v = Variable()
> +            v.guid = guid
> +            vardef = VarDefine.get(varname)
> +            if vardef is None:
> +                for var in VarDefine:
> +                    if VarDefine[var]['Type'] == varname:
> +                        vardef = VarDefine[var]
> +                        break
> +                else:
> +                    continue
> +            v.attributes = vardef['Attributes']
> +            v.mType = vardef['Type']
> +            v.mAlign = VarAttributes[v.mType]['Alignment']
> +            v.mTotalSize = VarAttributes[v.mType]['TotalSize']
> +            v.Struct = DataStruct[v.mType]
> +            v.mName = varname
> +            v.cDefs = cStructDefs
> +            for fieldinfo in VarDataDict.get((guid, varname), []):
> +                vf = VarField()
> +                vf.Offset = fieldinfo['Offset']
> +                vf.Value = fieldinfo['Value']
> +                vf.Size = fieldinfo['Size']
> +                v.fields.setdefault(
> +                    int(fieldinfo['DefaultStore'], 10), []).append(vf)
> +            v.serial()
> +            v.pack()
> +            self.NvVarInfo.append(v)
> +
> +    def PackDeltaData(self):
> +
> +        default_id_set = set()
> +        for v in self.NvVarInfo:
> +            default_id_set |= set(v.mBin.keys())
> +
> +        if default_id_set:
> +            default_id_set.remove(0)
> +        delta_buff_set = {}
> +        for defaultid in default_id_set:
> +            delta_buff = b''
> +            for v in self.NvVarInfo:
> +                delta_list = v.delta.get(defaultid,[])
> +                for delta in delta_list:
> +                    delta_data = DELTA_DATA()
> +                    delta_data.Offset, delta_data.Value = delta
> +                    delta_buff += PackStruct(delta_data)
> +            delta_buff_set[defaultid] = delta_buff
> +
> +        return delta_buff_set
> +
> +    def PackDefaultData(self):
> +
> +        default_data_header = DEFAULT_DATA()
> +        default_data_header.HeaderSize = sizeof(DEFAULT_DATA)
> +        default_data_header.DefaultInfo.DefaultId = 0x0
> +        default_data_header.DefaultInfo.BoardId = 0x0
> +        default_data_header_buffer = PackStruct(default_data_header)
> +
> +
> +        variable_store = VARIABLE_STORE_HEADER()
> +        variable_store.Signature = AuthVarGuid
> +
> +        variable_store_size = Get_Occupied_Size(sizeof(DEFAULT_DATA) + sizeof(VARIABLE_STORE_HEADER), 4)
> +        for v in self.NvVarInfo:
> +            variable_store_size += Get_Occupied_Size(len(v.mBin[0]), 4)
> +
> +        variable_store.Size = variable_store_size
> +        variable_store.Format = VARIABLE_STORE_FORMATTED
> +        variable_store.State = VARIABLE_STORE_HEALTHY
> +        variable_store.Reserved = 0x0
> +        variable_store.Reserved2 = 0x0
> +
> +        variable_storage_header_buffer = PackStruct(variable_store)
> +
> +        variable_data = b''
> +        v_offset = 0
> +        for v in self.NvVarInfo:
> +            v.update_delta_offset(v_offset)
> +            variable_data += Occupied_Size(v.mBin[0],4)
> +            v_offset += Get_Occupied_Size(len(v.mBin[0]),4)
> +
> +
> +        final_buff = Occupied_Size(default_data_header_buffer + variable_storage_header_buffer,4) + variable_data
> +
> +        return final_buff
> +
> +    def generate(self, jsonlistfile,output_folder):
> +        if not os.path.exists(jsonlistfile):
> +            return
> +        if not os.path.exists(output_folder):
> +            os.makedirs(output_folder)
> +        try:
> +            with open(jsonlistfile,"r") as fd:
> +                filelist = fd.readlines()
> +            genVar = DefaultVariableGenerator()
> +            genVar.LoadNvVariableInfo(filelist)
> +            with open(os.path.join(output_folder, "default.bin"), "wb") as fd:
> +                fd.write(genVar.PackDefaultData())
> +
> +            delta_set = genVar.PackDeltaData()
> +            for default_id in delta_set:
> +                with open(os.path.join(output_folder, "defaultdelta_%s.bin" % default_id), "wb") as fd:
> +                    fd.write(delta_set[default_id])
> +        except:
> +            print("generate varbin file failed")
> +
> +
> +
> diff --git a/BaseTools/Source/Python/AutoGen/ModuleAutoGen.py b/BaseTools/Source/Python/AutoGen/ModuleAutoGen.py
> index d70b0d7ae828..0daf3352f91b 100755
> --- a/BaseTools/Source/Python/AutoGen/ModuleAutoGen.py
> +++ b/BaseTools/Source/Python/AutoGen/ModuleAutoGen.py
> @@ -433,10 +433,19 @@ class ModuleAutoGen(AutoGen):
>     ## Return the directory to store auto-gened source files of the module
>     @cached_property
>     def DebugDir(self):
>         return _MakeDir((self.BuildDir, "DEBUG"))
> 
> +
> +    @cached_property
> +    def DefaultVarJsonFiles(self):
> +        rt = []
> +        for SrcFile in self.SourceFileList:
> +            if SrcFile.Ext.lower() == '.vfr':
> +                rt.append(os.path.join(self.DebugDir,os.path.join(os.path.dirname(SrcFile.File), "{}_var.json".format(SrcFile.BaseName))))
> +        return rt
> +
>     ## Return the path of custom file
>     @cached_property
>     def CustomMakefile(self):
>         RetVal = {}
>         for Type in self.Module.CustomMakefile:
> diff --git a/BaseTools/Source/Python/AutoGen/ModuleAutoGenHelper.py b/BaseTools/Source/Python/AutoGen/ModuleAutoGenHelper.py
> index 036fdac3d7df..b46d041f58ab 100644
> --- a/BaseTools/Source/Python/AutoGen/ModuleAutoGenHelper.py
> +++ b/BaseTools/Source/Python/AutoGen/ModuleAutoGenHelper.py
> @@ -644,10 +644,14 @@ class PlatformInfo(AutoGenInfo):
>                             if Attr != 'PATH':
>                                 BuildOptions[ExpandedTool][Attr] += " " + mws.handleWsMacro(Value)
>                             else:
>                                 BuildOptions[ExpandedTool][Attr] = mws.handleWsMacro(Value)
> 
> +        if self.DataPipe.Get("GenDefaultVarBin"):
> +            if BuildOptions.get('VFR',{}).get('FLAGS'):
> +                BuildOptions['VFR']['FLAGS'] += " " + "--variable"
> +
>         return BuildOptions, BuildRuleOrder
> 
>     def ApplyLibraryInstance(self,module):
>         alldeps = self.DataPipe.Get("DEPS")
>         if alldeps is None:
> diff --git a/BaseTools/Source/Python/Common/GlobalData.py b/BaseTools/Source/Python/Common/GlobalData.py
> index 61ab3f7e24cd..c68ca8fbb3f7 100755
> --- a/BaseTools/Source/Python/Common/GlobalData.py
> +++ b/BaseTools/Source/Python/Common/GlobalData.py
> @@ -88,10 +88,15 @@ gIgnoreSource = False
> #
> gFdfParser = None
> 
> BuildOptionPcd = []
> 
> +#
> +# Build flag for generate default variable binary file
> +#
> +gGenDefaultVarBin = False
> +
> #
> # Mixed PCD name dict
> #
> MixedPcd = {}
> 
> diff --git a/BaseTools/Source/Python/build/build.py b/BaseTools/Source/Python/build/build.py
> index 02b489892422..2f6fc6b20faf 100755
> --- a/BaseTools/Source/Python/build/build.py
> +++ b/BaseTools/Source/Python/build/build.py
> @@ -750,10 +750,11 @@ class Build():
>         GlobalData.gUseHashCache = BuildOptions.UseHashCache
>         GlobalData.gBinCacheDest   = BuildOptions.BinCacheDest
>         GlobalData.gBinCacheSource = BuildOptions.BinCacheSource
>         GlobalData.gEnableGenfdsMultiThread = not BuildOptions.NoGenfdsMultiThread
>         GlobalData.gDisableIncludePathCheck = BuildOptions.DisableIncludePathCheck
> +        GlobalData.gGenDefaultVarBin = BuildOptions.GenDefaultVarBin
> 
>         if GlobalData.gBinCacheDest and not GlobalData.gUseHashCache:
>             EdkLogger.error("build", OPTION_NOT_SUPPORTED, ExtraData="--binary-destination must be used together with --hash.")
> 
>         if GlobalData.gBinCacheSource and not GlobalData.gUseHashCache:
> @@ -1459,10 +1460,14 @@ class Build():
>             self.BuildModules = []
>             return True
> 
>         # genfds
>         if Target == 'fds':
> +            if GlobalData.gGenDefaultVarBin:
> +                from AutoGen.GenDefaultVar import DefaultVariableGenerator
> +                variable_info_filelist = os.path.join(AutoGenObject.BuildDir,"variable_info_filelist.txt")
> +                DefaultVariableGenerator().generate(variable_info_filelist,AutoGenObject.FvDir)
>             if GenFdsApi(AutoGenObject.GenFdsCommandDict, self.Db):
>                 EdkLogger.error("build", COMMAND_FAILURE)
>             Threshold = self.GetFreeSizeThreshold()
>             if Threshold:
>                 self.CheckFreeSizeThreshold(Threshold, AutoGenObject.FvDir)
> @@ -2247,10 +2252,19 @@ class Build():
>         AutoGenIdFile = os.path.join(GlobalData.gConfDirectory,".AutoGenIdFile.txt")
>         with open(AutoGenIdFile,"w") as fw:
>             fw.write("Arch=%s\n" % "|".join((Wa.ArchList)))
>             fw.write("BuildDir=%s\n" % Wa.BuildDir)
>             fw.write("PlatformGuid=%s\n" % str(Wa.AutoGenObjectList[0].Guid))
> +        variable_info_filelist = os.path.join(Wa.BuildDir,"variable_info_filelist.txt")
> +        vfr_var_json = []
> +        if GlobalData.gGenDefaultVarBin:
> +            for ma in self.AllModules:
> +                vfr_var_json.extend(ma.DefaultVarJsonFiles)
> +            SaveFileOnChange(variable_info_filelist, "\n".join(vfr_var_json), False)
> +        else:
> +            if os.path.exists(variable_info_filelist):
> +                os.remove(variable_info_filelist)
> 
>         if GlobalData.gBinCacheSource:
>             BuildModules.extend(self.MakeCacheMiss)
>         elif GlobalData.gUseHashCache and not GlobalData.gBinCacheDest:
>             BuildModules.extend(self.PreMakeCacheMiss)
> @@ -2359,10 +2373,14 @@ class Build():
> 
>                     if self.Fdf:
>                         #
>                         # Generate FD image if there's a FDF file found
>                         #
> +                        if GlobalData.gGenDefaultVarBin:
> +                            from AutoGen.GenDefaultVar import DefaultVariableGenerator
> +                            variable_info_filelist = os.path.join(Wa.BuildDir,"variable_info_filelist.txt")
> +                            DefaultVariableGenerator().generate(variable_info_filelist,Wa.FvDir)
>                         GenFdsStart = time.time()
>                         if GenFdsApi(Wa.GenFdsCommandDict, self.Db):
>                             EdkLogger.error("build", COMMAND_FAILURE)
>                         Threshold = self.GetFreeSizeThreshold()
>                         if Threshold:
> diff --git a/BaseTools/Source/Python/build/buildoptions.py b/BaseTools/Source/Python/build/buildoptions.py
> index 39d92cff209d..6886ba7f8eb6 100644
> --- a/BaseTools/Source/Python/build/buildoptions.py
> +++ b/BaseTools/Source/Python/build/buildoptions.py
> @@ -99,7 +99,8 @@ class MyOptionParser():
>         Parser.add_option("--hash", action="store_true", dest="UseHashCache", default=False, help="Enable hash-based caching during build process.")
>         Parser.add_option("--binary-destination", action="store", type="string", dest="BinCacheDest", help="Generate a cache of binary files in the specified directory.")
>         Parser.add_option("--binary-source", action="store", type="string", dest="BinCacheSource", help="Consume a cache of binary files from the specified directory.")
>         Parser.add_option("--genfds-multi-thread", action="store_true", dest="GenfdsMultiThread", default=True, help="Enable GenFds multi thread to generate ffs file.")
>         Parser.add_option("--no-genfds-multi-thread", action="store_true", dest="NoGenfdsMultiThread", default=False, help="Disable GenFds multi thread to generate ffs file.")
> +        Parser.add_option("--gen-default-variable-bin", action="store_true", dest="GenDefaultVarBin", default=False, help="Generate default variable binary file.")
>         Parser.add_option("--disable-include-path-check", action="store_true", dest="DisableIncludePathCheck", default=False, help="Disable the include path check for outside of package.")
>         self.BuildOption, self.BuildTarget = Parser.parse_args()
> -- 
> 2.18.0.windows.1
> 
> 
> 
> 
> 
>