This updates the PrePiHobListPointerLib implementation in ArmPlatformPkg
to move away from ArmPlatformGlobalVariableLib and instead use the thread
ID CPU registers (TPIDRURW and TPIDR_EL0 for v7 and v8, respectively)
for storing the HobList pointer.
Since PrePiHobListPointerLib is specific to PrePi (where PEI core is skipped)
we can share these registers with the PEI services table pointer. By the
same reasoning, the PEI services table pointer and the HobList pointer
already shared the same offset in the ArmPlatformGlobalVariable array.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18982 6f19259b-4bc3-4df7-8a09-765794883524
This library hides where the 'XIP' Global Variable are located in the memory.
It is expected the Sec/PrePi modules define the Global Variable area through
the GlobalVariable HOB.
The ArmPlatformGlobalVariableLib library allows access to global variables by
their offsets in this region.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12420 6f19259b-4bc3-4df7-8a09-765794883524
In the PrePi module, the global variables are located at the top of the stack.
At the opposite of the PeiCore where the global variables are located in the
middle of the stack. The top stack region is reserved for Temporary Memory.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12167 6f19259b-4bc3-4df7-8a09-765794883524
When using ArmPlatformPkg/PrePeiCore or ArmPlatformPkg/PrePi, the global variable during
the XIP phase are stored on the top of the stack.
Global variables are defined by their PCD offset from the top of this stack.
For example, the HobListPtr is defined at the offset PcdHobListPtrGlobalOffset.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11958 6f19259b-4bc3-4df7-8a09-765794883524