[PATCH v2 04/13] ArmPkg: Introduce support for PcdFfaEnable

["Sughosh Ganu" <sughosh.ganu@linaro.org>]

The Secure Partition(SP) can request services from the Secure
Partition Manager Core(SPMC) either through FF-A calls or through the
existing SVC calls. Add a feature flag Pcd for enabling the FF-A
method -- when this is set to FALSE, the SP uses the existing SVC
calls for making the requests.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
---
 ArmPkg/ArmPkg.dec | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec
index eaf1072d9e..507e16844c 100644
--- a/ArmPkg/ArmPkg.dec
+++ b/ArmPkg/ArmPkg.dec
@@ -78,6 +78,12 @@
   # Define if the GICv3 controller should use the GICv2 legacy
   gArmTokenSpaceGuid.PcdArmGicV3WithV2Legacy|FALSE|BOOLEAN|0x00000042
 
+  ## Used to select method for requesting services from S-EL1.<BR><BR
+  #   TRUE  - Selects FF-A calls for communication between S-EL0 and SPMC.<BR>
+  #   FALSE - Selects SVC calls for communication between S-EL0 and SPMC.<BR>
+  # @Prompt Enable FF-A support.
+  gArmTokenSpaceGuid.PcdFfaEnable|FALSE|BOOLEAN|0x0000005B
+
 [PcdsFeatureFlag.ARM]
   # Whether to map normal memory as non-shareable. FALSE is the safe choice, but
   # TRUE may be appropriate to fix performance problems if you don't care about
-- 
2.17.1