diff options
Diffstat (limited to 'MdeModulePkg')
| -rw-r--r-- | MdeModulePkg/Universal/PCD/Dxe/Service.h | 558 |
1 files changed, 262 insertions, 296 deletions
diff --git a/MdeModulePkg/Universal/PCD/Dxe/Service.h b/MdeModulePkg/Universal/PCD/Dxe/Service.h index 04f3170..2a1f719 100644 --- a/MdeModulePkg/Universal/PCD/Dxe/Service.h +++ b/MdeModulePkg/Universal/PCD/Dxe/Service.h @@ -1066,299 +1066,265 @@ extern EFI_LOCK mPcdDatabaseLock; #endif
-////////////////////////////////////////////////////////////////////////////////////////////////////
-/// ///
-/// Following code is an example for auto-generated PCD database to hold all dynamic/dynamicex ///
-/// PCD's value for one given platform. And following sample comes from autogen.h/autogen.c of ///
-/// PCD Dxe driver for NT32 platform. ///
-/// ///
-/// The PCD database is stored into a big structure - PCD_DATABASE which is consisted of ///
-/// PEI PCD database structure and DXE PCD database structure. ///
-/// ///
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-// //
-// // Common definitions
-// //
-// typedef UINT8 SKU_ID;
-//
-// //
-// // A PCD offset value is consisted as follows:
-// // 32 ------------- 28 ---------- 24 -------- 0
-// // | PCD type mask | Datum Type | Offset |
-// // -------------------------------------------
-//
-// #define PCD_TYPE_SHIFT 28 // 28 ~ 32 bit hold PCD type information
-//
-// #define PCD_TYPE_DATA (0x0 << PCD_TYPE_SHIFT)
-// #define PCD_TYPE_HII (0x8 << PCD_TYPE_SHIFT)
-// #define PCD_TYPE_VPD (0x4 << PCD_TYPE_SHIFT)
-// #define PCD_TYPE_SKU_ENABLED (0x2 << PCD_TYPE_SHIFT)
-// #define PCD_TYPE_STRING (0x1 << PCD_TYPE_SHIFT)
-//
-// #define PCD_TYPE_ALL_SET (PCD_TYPE_DATA | PCD_TYPE_HII | PCD_TYPE_VPD | PCD_TYPE_SKU_ENABLED | PCD_TYPE_STRING)
-//
-// #define PCD_DATUM_TYPE_SHIFT 24 // 24 ~ 28 bit hold datum type information
-//
-// #define PCD_DATUM_TYPE_POINTER (0x0 << PCD_DATUM_TYPE_SHIFT)
-// #define PCD_DATUM_TYPE_UINT8 (0x1 << PCD_DATUM_TYPE_SHIFT)
-// #define PCD_DATUM_TYPE_UINT16 (0x2 << PCD_DATUM_TYPE_SHIFT)
-// #define PCD_DATUM_TYPE_UINT32 (0x4 << PCD_DATUM_TYPE_SHIFT)
-// #define PCD_DATUM_TYPE_UINT64 (0x8 << PCD_DATUM_TYPE_SHIFT)
-//
-// #define PCD_DATUM_TYPE_ALL_SET (PCD_DATUM_TYPE_POINTER |
-// PCD_DATUM_TYPE_UINT8 |
-// PCD_DATUM_TYPE_UINT16 |
-// PCD_DATUM_TYPE_UINT32 |
-// PCD_DATUM_TYPE_UINT64)
-//
-// #define PCD_DATABASE_OFFSET_MASK (~(PCD_TYPE_ALL_SET | PCD_DATUM_TYPE_ALL_SET))
-//
-// typedef struct {
-// UINT32 ExTokenNumber;
-// UINT16 LocalTokenNumber; // PCD Number of this particular platform build
-// UINT16 ExGuidIndex; // Index of GuidTable
-// } DYNAMICEX_MAPPING;
-//
-// typedef struct {
-// UINT32 SkuDataStartOffset; //We have to use offsetof MACRO as we don't know padding done by compiler
-// UINT32 SkuIdTableOffset; //Offset from the PCD_DB
-// } SKU_HEAD;
-//
-// typedef struct {
-// UINT16 GuidTableIndex; // Offset in Guid Table in units of GUID.
-// UINT16 StringIndex; // Offset in String Table in units of UINT16.
-// UINT16 Offset; // Offset in Variable
-// UINT16 DefaultValueOffset; // Offset of the Default Value
-// } VARIABLE_HEAD;
-//
-// typedef struct {
-// UINT32 Offset;
-// } VPD_HEAD;
-//
-// typedef UINT16 STRING_HEAD;
-//
-// typedef UINT16 SIZE_INFO;
-//
-// #define offsetof(s,m) (UINT32) (UINTN) &(((s *)0)->m)
-//
-//
-// #define PEI_GUID_TABLE_SIZE 1
-// #define PEI_STRING_TABLE_SIZE 1
-// #define PEI_SKUID_TABLE_SIZE 1
-// #define PEI_LOCAL_TOKEN_NUMBER_TABLE_SIZE 3
-// #define PEI_LOCAL_TOKEN_NUMBER 3
-// #define PEI_EXMAPPING_TABLE_SIZE 1
-// #define PEI_EX_TOKEN_NUMBER 0
-// #define PEI_SIZE_TABLE_SIZE 2
-// #define PEI_GUID_TABLE_EMPTY TRUE
-// #define PEI_STRING_TABLE_EMPTY TRUE
-// #define PEI_SKUID_TABLE_EMPTY TRUE
-// #define PEI_DATABASE_EMPTY FALSE
-// #define PEI_EXMAP_TABLE_EMPTY TRUE
-//
-// //
-// // PEI database structure for dynamic/dynamicex PCD which has default value.
-// //
-// typedef struct {
-//
-//
-//
-//
-//
-// DYNAMICEX_MAPPING ExMapTable[PEI_EXMAPPING_TABLE_SIZE]; // table for mapping dynamicex token number to local token number
-// UINT32 LocalTokenNumberTable[PEI_LOCAL_TOKEN_NUMBER_TABLE_SIZE]; // table for local token number
-// GUID GuidTable[PEI_GUID_TABLE_SIZE]; // table for token guid
-//
-//
-// UINT16 StringTable[1]; /* _ */ // table for unicode string type PCD's value
-//
-// SIZE_INFO SizeTable[PEI_SIZE_TABLE_SIZE]; // table for PCD size information
-//
-//
-//
-//
-//
-//
-// UINT8 SkuIdTable[PEI_SKUID_TABLE_SIZE]; // table for SKU IDs
-// SKU_ID SystemSkuId; // system SKU ID
-// } PEI_PCD_DATABASE_INIT;
-//
-// //
-// // PEI database structure for dynamic/dynamicex PCD which has no default value.
-// //
-// typedef struct {
-//
-//
-// UINT32 PcdFlashNvStorageVariableBase_a1aff049_fdeb_442a_b320_13ab4cb72bbc[1]; // PCD entry for PcdFlashNvStorageVariableBase
-// UINT32 PcdFlashNvStorageFtwSpareBase_a1aff049_fdeb_442a_b320_13ab4cb72bbc[1]; // PCD entry for PcdFlashNvStorageFtwSpareBase
-// UINT32 PcdFlashNvStorageFtwWorkingBase_a1aff049_fdeb_442a_b320_13ab4cb72bbc[1]; // PCD entry for PcdFlashNvStorageFtwWorkingBase
-//
-//
-//
-//
-// } PEI_PCD_DATABASE_UNINIT;
-//
-// #define PCD_PEI_SERVICE_DRIVER_VERSION 2
-//
-// typedef struct {
-// PEI_PCD_DATABASE_INIT Init;
-// PEI_PCD_DATABASE_UNINIT Uninit;
-// } PEI_PCD_DATABASE;
-//
-// #define PEI_NEX_TOKEN_NUMBER (PEI_LOCAL_TOKEN_NUMBER - PEI_EX_TOKEN_NUMBER)
-//
-// #define DXE_GUID_TABLE_SIZE 1
-// #define DXE_STRING_TABLE_SIZE 212
-// #define DXE_SKUID_TABLE_SIZE 1
-// #define DXE_LOCAL_TOKEN_NUMBER_TABLE_SIZE 9
-// #define DXE_LOCAL_TOKEN_NUMBER 9
-// #define DXE_EXMAPPING_TABLE_SIZE 1
-// #define DXE_EX_TOKEN_NUMBER 0
-// #define DXE_SIZE_TABLE_SIZE 16
-// #define DXE_GUID_TABLE_EMPTY TRUE
-// #define DXE_STRING_TABLE_EMPTY FALSE
-// #define DXE_SKUID_TABLE_EMPTY TRUE
-// #define DXE_DATABASE_EMPTY FALSE
-// #define DXE_EXMAP_TABLE_EMPTY TRUE
-//
-// typedef struct {
-//
-//
-//
-//
-//
-// DYNAMICEX_MAPPING ExMapTable[DXE_EXMAPPING_TABLE_SIZE];
-// UINT32 LocalTokenNumberTable[DXE_LOCAL_TOKEN_NUMBER_TABLE_SIZE];
-// GUID GuidTable[DXE_GUID_TABLE_SIZE];
-// STRING_HEAD PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-// STRING_HEAD PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4[1];
-//
-//
-// UINT16 StringTable[6]; /* PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_1[26]; /* PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_2[10]; /* PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_3[13]; /* PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_4[26]; /* PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_5[51]; /* PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_6[54]; /* PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// UINT16 StringTable_7[26]; /* PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-//
-// SIZE_INFO SizeTable[DXE_SIZE_TABLE_SIZE];
-// UINT16 PcdPlatformBootTimeOutDefault_a1aff049_fdeb_442a_b320_13ab4cb72bbc[1];
-//
-//
-//
-//
-//
-//
-// UINT8 SkuIdTable[DXE_SKUID_TABLE_SIZE];
-//
-// } DXE_PCD_DATABASE_INIT;
-//
-// typedef struct {
-// UINT8 dummy; /* PCD_DATABASE_UNINIT is emptry */
-//
-//
-//
-//
-//
-// } DXE_PCD_DATABASE_UNINIT;
-//
-// #define PCD_DXE_SERVICE_DRIVER_VERSION 2
-//
-// typedef struct {
-// DXE_PCD_DATABASE_INIT Init;
-// DXE_PCD_DATABASE_UNINIT Uninit;
-// } DXE_PCD_DATABASE;
-//
-// #define DXE_NEX_TOKEN_NUMBER (DXE_LOCAL_TOKEN_NUMBER - DXE_EX_TOKEN_NUMBER)
-//
-// typedef struct {
-// PEI_PCD_DATABASE PeiDb;
-// DXE_PCD_DATABASE DxeDb;
-// } PCD_DATABASE;
-//
-// #define PCD_TOTAL_TOKEN_NUMBER (PEI_LOCAL_TOKEN_NUMBER + DXE_LOCAL_TOKEN_NUMBER)
-//
-//
-// DXE_PCD_DATABASE_INIT gDXEPcdDbInit = {
-//
-//
-//
-//
-// /* VPD */
-//
-// /* ExMapTable */
-// {
-// { 0, 0, 0 },
-//
-// },
-// /* LocalTokenNumberTable */
-// {
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4) | PCD_DATUM_TYPE_POINTER | PCD_TYPE_STRING,
-// offsetof(DXE_PCD_DATABASE, Init.PcdPlatformBootTimeOutDefault_a1aff049_fdeb_442a_b320_13ab4cb72bbc) | PCD_TYPE_DATA | PCD_DATUM_TYPE_UINT16,
-//
-// },
-// /* GuidTable */
-// {
-// {0x00000000, 0x0000, 0x0000, {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}},
-//
-// },
-// { 0 }, /* PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 6 }, /* PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 32 }, /* PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 42 }, /* PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 55 }, /* PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 81 }, /* PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 132 }, /* PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-// { 186 }, /* PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4[1] */
-//
-//
-// /* StringTable */
-// L"64!64", /* PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"UGA Window 1!UGA Window 2", /* PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"COM1!COM2", /* PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"FW;40960;512", /* PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"UGA Window 1!UGA Window 2", /* PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"a:RW;2880;512!d:RO;307200;2048!j:RW;262144;512", /* PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L".!..\\..\\..\\..\\EdkShellBinPkg\\Bin\\Ia32\\Apps", /* PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// L"Bus Driver Console Window", /* PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-
-// /* SizeTable */
-// {
-// 10, 10, /* PcdWinNtMemorySize_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 50, 50, /* PcdWinNtGop_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 18, 18, /* PcdWinNtSerialPort_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 24, 24, /* PcdWinNtVirtualDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 50, 50, /* PcdWinNtUga_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 100, 92, /* PcdWinNtPhysicalDisk_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 106, 98, /* PcdWinNtFileSystem_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-// 50, 50, /* PcdWinNtConsole_0d79a645_1d91_40a6_a81f_61e6982b32b4 */
-//
-// },
-// { 10 }, /* PcdPlatformBootTimeOutDefault_a1aff049_fdeb_442a_b320_13ab4cb72bbc[1] */
-//
-//
-//
-//
-//
-//
-// /* SkuIdTable */
-// { 0, },
-//
-//};
-
+////////////////////////////////////////////////////////////////////////////////
+// //
+// Introduction of PCD database //
+// //
+////////////////////////////////////////////////////////////////////////////////
+/**
+ 1, Introduction
+ PEI PCD database hold all dynamic type PCD information used in PEI phase.
+ The structure of PEI PCD database is generated by build tools according to
+ dynamic PCD usage for specified platform.
+
+ 2, Dynamic Type PCD
+ Dynamic type PCD is designed for accessing setting which value is determined
+ dynamic. In contrast, the value of static type PCD (FeatureFlag, FixedPcd,
+ PatchablePcd) is fixed in final generated FD image in build time.
+
+ 2.1 The "dynamic" determination means:
+ a) The PCD value is produced by someone driver and consumed by other driver
+ in execution time.
+ b) The PCD value is set/get by user from FrontPage.
+ c) The PCD value is produced by platform OEM specified area.
+
+ 2.2 According to distribution mehod, dynamic PCD could be classfied as:
+ a) Dynamic:
+ This type PCD is used for module in source distribution which will be
+ built in platform.
+ b) DynamicEx:
+ This type PCD is used for module in binary distribution which will be
+ will not built.
+
+ 2.3 According to storage method, dynamic PCD could be classfied as:
+ a) Default Storage:
+ - The value is stored in PCD database maintained by PCD database in boot
+ time memory which is built as a guid hob in PEI phase.
+ - This type is used for communication between PEIM/DXE driver, DXE/DXE
+ driver. But all set/get value will be losted after boot-time memory
+ is turn off.
+ - [PcdsDynamicDefault]/[PcdsDynamicExDefault] is used as section name
+ for this type PCD in platform DSC file.
+
+ b) Variable Storage:
+ - The value is stored in variable area.
+ - As default storage type, this type PCD could used for communication.
+ But beside it, this type PCD could be used store the value associating
+ with HII setting via variable technology.
+ - In PEI phase, the PCD value could only be got but can not be set due
+ to variable area is readonly for PEI phase.
+ - [PcdsDynamicHii]/[PcdsDynamicExHii] is used as section name for this
+ type PCD in platform DSC file.
+
+ c) OEM specificed storage area:
+ - The value is stored in OEM specified area, the base address is specified
+ by a FixedAtBuild PCD PcdVpdBaseAddress.
+ - The area is read only for PEI and DXE phase.
+ - [PcdsDynamicVpd]/[PcdsDynamicExVpd] is used as section name for this
+ type PCD in platform DSC file.
+
+ Note: The default value of dynamic PCD are storaged in memory maintained
+ by PEI/DXE PCD drvier.
+
+ 2.4 When and how to use dynamic PCD
+ Module developer do not care the used PCD is dynamic or static when writting
+ source code/INF. Dynamic PCD and dynamic type is pointed by platform integrator
+ in platform DSC file. Please ref section 2.3 to get matching between dynamic
+ PCD type and section name in DSC file.
+
+ 3, PCD database:
+ Although dynamic PCD could be in different storage type as above description,
+ but the basic information and default value for all dynamic PCD is hold
+ by PCD database maintained by PEI/DXE driver.
+
+ As whole EFI BIOS boot path is divided into PEI/DXE phase, the PCD database
+ also is divided into Pei/Dxe database maintaied by PcdPeim/PcdDxe driver separatly.
+ To make PcdPeim's driver image smaller, PEI PCD database only hold all dynamic
+ PCD information used in PEI phase or use in both PEI/DXE phase. And DXE PCD
+ database contains all PCDs used in PEI/DXE phase in memory.
+
+ Build tool will generate PCD database into some C structure and variable for
+ PEI/DXE PCD driver according to dynamic PCD section in platform DSC file.
+
+ 3.1 PcdPeim and PcdDxe
+ PEI PCD database is maintained by PcdPeim driver run from flash. PcdPeim driver
+ build guid hob in temporary memory and copy auto-generated C structure
+ to temporary memory for PEI PCD database.
+ DXE PCD database is maintained by PcdDxe driver.At entry point of PcdDxe driver,
+ a new PCD database is allocated in boot-time memory which including all
+ PEI PCD and DXE PCD entry.
+
+ Pcd driver should run as early as possible before any other driver access
+ dynamic PCD's value. PEI/DXE "Apriori File" mechanism make it possible by
+ making PcdPeim/PcdDxe as first dispatching driver in PEI/DXE phase.
+
+ 3.2 Token space Guid/Token number, Platform token, Local token number
+ Dynamic PCD
+ +-----------+ +---------+
+ |TokenSpace | |Platform |
+ | Guid | build tool | Token |
+ | + +-------------->| Number |
+ | Token | +---------+`._
+ | Number | `.
+ +-----------+ `. +------+
+ `-|Local |
+ |Token |
+ DynamicEx PCD ,-|Number|
+ +-----------+ ,-' +------+
+ |TokenSpace | ,-'
+ | Guid | _,-'
+ | + +.'
+ | Token |
+ | Number |
+ +-----------+
+
+
+ 3.2.1 Pair of Token space guid + Token number
+ Any type PCD is identified by pair of "TokenSpaceGuid + TokeNumber". But it
+ is not easy maintained by PCD driver, and hashed token number will make
+ searching slowly.
+
+ 3.2.2 Platform Token Number
+ "Platform token number" concept is introduced for mapping to a pair of
+ "TokenSpaceGuid + TokenNumber". The platform token number is generated by
+ build tool in autogen.h and all of them are continual in a platform scope
+ started from 1.(0 meaning invalid internal token number)
+ With auto-generated "platform token number", PcdGet(PcdSampleDynamicPcd)
+ in source code is translated to LibPcdGet(_PCD_TOKEN_PcdSampleDynamicPcd)
+ in autogen.h.
+ Notes: The mapping between pair of "tokenspace guid + token number" and
+ "internal token number" need build tool establish, so "platform token number"
+ mechanism is not suitable for binary module which use DynamicEx type PCD.
+ To access a dynamicEx type PCD, pair of "token space guid/token number" all need
+ to be specificed for PcdSet/PcdGet accessing macro.
+
+ Platform Token Number is started from 1, and inceased continuous. From whole
+ platform scope, there are two zones: PEI Zone and DXE Zone
+ | Platform Token Number
+ ----------|----------------------------------------------------------------
+ PEI Zone: | 1 ~ PEI_LOCAL_TOKEN_NUMBER
+ DXE Zone: | (PEI_LOCAL_TOKEN_NUMBER + 1) ~ (PEI_LOCAL_TOKEN_NUMBER + DXE_LOCAL_TOKEN_NUMBER)
+
+ 3.2.3 Local Token Number
+ To fast searching a PCD entry in PCD database, PCD driver translate
+ platform token number to local token number via a mapping table.
+ For binary DynamicEx type PCD, there is a another mapping table to translate
+ "token space guid + token number" to local token number directly.
+ Local token number is identifier for all internal interface in PCD PEI/DXE
+ driver.
+
+ A local token number is a 32-bit value in following meaning:
+ 32 ------------- 28 ---------- 24 -------- 0
+ | PCD type mask | Datum Type | Offset |
+ +-----------------------------------------+
+ where:
+ PCd type mask: indicate Pcd type from following macro:
+ PCD_TYPE_DATA
+ PCD_TYPE_HII
+ PCD_TYPE_VPD
+ PCD_TYPE_SKU_ENABLED
+ PCD_TYPE_STRING
+ Datum Type : indicate PCD vaue type from following macro:
+ PCD_DATUM_TYPE_POINTER
+ PCD_DATUM_TYPE_UINT8
+ PCD_DATUM_TYPE_UINT16
+ PCD_DATUM_TYPE_UINT32
+ PCD_DATUM_TYPE_UINT64
+ Offset : indicate the related offset of PCD value in PCD database array.
+ Based on local token number, PCD driver could fast determine PCD type, value
+ type and get PCD entry from PCD database.
+
+ 3.3 PCD Database C structure.
+ PCD Database C structure is generated by build tools in PCD driver's autogen.h/
+ autogen.c file. In generated C structure, following information is stored:
+ - ExMapTable: This table is used translate a binary dynamicex type PCD's
+ "tokenguid + token" to local token number.
+ - LocalTokenNumberTable:
+ This table stores all local token number in array, use "Internal
+ token number" as array index to get PCD entry's offset fastly.
+ - SizeTable: This table stores the size information for all PCD entry.
+ - GuidTable: This table stores guid value for DynamicEx's token space,
+ HII type PCD's variable.
+ - SkuIdTable: TBD
+ - SystemSkuId: TBD
+ - PCD value structure:
+ Every PCD has a value record in PCD database. For different
+ datum type PCD has different record structure which will be
+ introduced in 3.3.1
+
+ In a PCD database structure, there are two major area: Init and UnInit.
+ Init area is use stored above PCD internal structure such as ExMapTable,
+ LocalTokenNumberTable etc and the (default) value of PCD which has default
+ value specified in platform DSC file.
+ Unint area is used stored the value of PCD which has no default value in
+ platform DSC file, the value of NULL, 0 specified in platform DSC file can
+ be seemed as "no default value".
+
+ 3.3.1 Simple Sample PCD Database C Structure
+ A general sample of PCD database structue is as follows:
+ typedef struct _PCD_DATABASE {
+ typedef struct _PCD_DATABASE_INIT {
+ //===== Following is PCD database internal maintain structures
+ DYNAMICEX_MAPPING ExMapTable[PEI_EXMAPPING_TABLE_SIZE];
+ UINT32 LocalTokenNumberTable[PEI_LOCAL_TOKEN_NUMBER_TABLE_SIZE];
+ GUID GuidTable[PEI_GUID_TABLE_SIZE];
+ SIZE_INFO SizeTable[PEI_SIZE_TABLE_SIZE];
+ UINT8 SkuIdTable[PEI_SKUID_TABLE_SIZE];
+ SKU_ID SystemSkuId;
+
+ //===== Following is value structure for PCD with default value
+ ....
+ ....
+ ....
+ } Init;
+ typedef struct _PCD_DATABSE_UNINIT {
+ //==== Following is value structure for PCD without default value
+ ....
+ ....
+ } UnInit;
+ }
+
+ 3.3.2 PCD value structure in PCD database C structure
+ The value's structure is generated by build tool in PCD database C structure.
+ The PCDs in different datum type has different value structure.
+
+ 3.3.2.1 UINT8/UINT16/UINT32/UINT64 datum type PCD
+ The C structure for these datum type PCD is just a UINT8/UINT16/UINT32/UINT64
+ data member in PCD database, For example:
+ UINT16 PcdHardwareErrorRecordLevel_d3705011_bc19_4af7_be16_f68030378c15_VariableDefault_0;
+ Above structure is generated by build tool, the member name is "PcdCName_Guidvalue"
+ Member type is UINT16 according to PcdHardwareErrorRecordLevel declaration
+ in DEC file.
+
+ 3.3.2.2 VOID* datum type PCD
+ The value of VOID* datum type PCD is a UINT8/UINT16 array in PCD database.
+
+ 3.3.2.2.1 VOID* - string type
+ If the default value for VOID* datum type PCD like L"xxx", the PCD is
+ used for unicode string, and C structure of this datum type PCD is
+ UINT16 string array in PCD database, for example:
+ UINT16 StringTable[29];
+ The number of 29 in above sample is max size of a unicode string.
+
+ If the default value for VOID* datum type PCD like "xxx", the PCD is
+ used for ascii string, and C structure of this datum type PCD is
+ UINT8 string array in PCD database, for example:
+ UINT8 StringTable[20];
+ The number of 20 in above sample is max size of a ascii string.
+
+ 3.3.2.2.2 VOID* - byte array
+ If the default value of VOID* datum type PCD like {'0x29', '0x01', '0xf2'}
+ the PCD is used for byte array. The generated structrue is same as
+ above ascii string table,
+ UINT8 StringTable[13];
+ The number of 13 in above sample is max size of byte array.
+
+ 3.3.3 Some utility structures in PCD Database
+ 3.3.3.1 GuidTable
+ GuidTable array is used to store all related GUID value in PCD database:
+ - Variable GUID for HII type PCD
+ - Token space GUID for dynamicex type PCD
+
+ 3.4 PEI PCD Database
+
+**/
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