ArmPlatform/ArmPlatformLib: Introduced ArmPlatformPeiBootAction()

This function allows platform to do any specific actions prior to
the start the PEI phase.
For instance, this function could be used by some platforms to initialize clocks that
are required at the early stage of the PEI phase.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Acked-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14347 6f19259b-4bc3-4df7-8a09-765794883524

ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/Arm/RTSMHelper.asm

@@ -22,6 +22,7 @@
 
   INCLUDE AsmMacroIoLib.inc
 
+  EXPORT    ArmPlatformPeiBootAction
   EXPORT    ArmGetCpuCountPerCluster
   EXPORT    ArmPlatformIsPrimaryCore
   EXPORT    ArmPlatformGetPrimaryCoreMpId
@@ -32,6 +33,10 @@
 
   AREA RTSMHelper, CODE, READONLY
 
+ArmPlatformPeiBootAction FUNCTION
+  bx    lr
+  ENDFUNC
+
 // IN None
 // OUT r0 = SCU Base Address
 ArmGetScuBaseAddress FUNCTION