Add more comments for PCD.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5576 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 9c521ae8c6778dfe94109370a232c5546a719578..addad6dd9a505b005d38c42ec676170e30cd9656 100644 (file)
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -109,6 +109,10 @@
 [PcdsFeatureFlag.common]\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdSupportUpdateCapsuleRest|FALSE|BOOLEAN|0x0001001d\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiPcdDatabaseTraverseEnabled|TRUE|BOOLEAN|0x00010020\r
+  ## If PcdDxePcdDatabaseTraverseEnabled is TRUE, PCD_PROTOCOL.GetNextToken can \r
+  #  get next PCD entry from PCD database, If FALSE, PCD_PROTOCOL.GetNextToken \r
+  #  return EFI_SUPPORTED.\r
+  #\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdDxePcdDatabaseTraverseEnabled|TRUE|BOOLEAN|0x00010021\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiPcdDatabaseSetEnabled|TRUE|BOOLEAN|0x00010030\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiPcdDatabaseGetSizeEnabled|TRUE|BOOLEAN|0x00010031\r
@@ -126,8 +130,15 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdUnicodeCollation2Support|TRUE|BOOLEAN|0x00010041\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdConOutGopSupport|TRUE|BOOLEAN|0x00010042\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdConOutUgaSupport|TRUE|BOOLEAN|0x00010043\r
+  ## If PcdPeiCoreImageLoaderSearchTeSectionFirst is TRUE, PeiCore will search TE section\r
+  #  firstly when loading an PEIM image, If FALSE, PeiCore will search PE section firstly.\r
+  #\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreImageLoaderSearchTeSectionFirst|TRUE|BOOLEAN|0x00010044\r
+  ## If PcdSupportHardwareErrorRecord is TRUE, support hardware error record via variable.\r
+  #  If FALSE, does not support.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdSupportHardwareErrorRecord|FALSE|BOOLEAN|0x00010045\r
+  ## If PcdUgaConsumeSupport is TRUE, EFI_UGA_DRAW_PROTOCOL is produced by platform.\r
+  #  Otherwice, EFI_UGA_DRAW_PROTOCOL is not produced by platform.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdUgaConsumeSupport|TRUE|BOOLEAN|0x00010046\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdTurnOffUsbLegacySupport|FALSE|BOOLEAN|0x00010047\r
 \r
@@ -139,14 +150,24 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdSupportFullConfigRoutingProtocol|TRUE|BOOLEAN|0x00010202\r
 \r
 [PcdsFixedAtBuild.common]\r
+  ## Dynamic type PCD can be registered callback function for Pcd setting action.\r
+  #  PcdMaxPeiPcdCallBackNumberPerPcdEntry indicate maximum number of callback function\r
+  #  for a dynamic PCD used in PEI phase.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxPeiPcdCallBackNumberPerPcdEntry|0x08|UINT32|0x0001000f\r
+  ## VPD type PCD allow developer point an absoluted physical address PcdVpdBaseAddress\r
+  #  to store PCD value. \r
+  #\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdVpdBaseAddress|0x0|UINT32|0x00010010\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxSizePopulateCapsule|0x6400000|UINT32|0x0001001e\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxSizeNonPopulateCapsule|0xa00000|UINT32|0x0001001f\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxPeiPerformanceLogEntries|40|UINT8|0x0001002f\r
+  ## Maximum number of FV is supported by PeiCore's dispatching.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxFvSupported|6|UINT32|0x00010030\r
+  ## Maximum PEIM count in every FV is supported by PeiCore's dispatching.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPeimPerFv|32|UINT32|0x00010031\r
+  ## Maximum stack size for PeiCore.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPeiStackSize|0x20000|UINT32|0x00010032\r
+  ## Maximum PPI count is supported by PeiCore's PPI database.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPpiSupported|64|UINT32|0x00010033\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdRealTimeClockUpdateTimeout|100000|UINT32|0x00010034\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase|0x0|UINT32|0x30000001\r
@@ -158,7 +179,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareSize|0x0|UINT32|0x30000014\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingBase|0x0|UINT32|0x30000010\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize|0x0|UINT32|0x30000011\r
+  ## Default timeout value for displaying progressing bar in before boot OS.\r
+  #  This value can be changed in BDS.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdPlatformBootTimeOutDefault|10|UINT16|0x40000001\r
+  ## error level for hardware recorder.\r
   gEfiMdeModulePkgTokenSpaceGuid.PcdHardwareErrorRecordLevel|1|UINT16|0x40000002\r
 \r
 [PcdsFixedAtBuild.IA32]\r