1 files changed, 32 insertions, 0 deletions
diff --git a/roms/edk2/ArmPkg/Library/ArmSmcLib/AArch64/ArmSmc.S b/roms/edk2/ArmPkg/Library/ArmSmcLib/AArch64/ArmSmc.S
new file mode 100644
index 000000000..4a8c2a8f5
--- /dev/null
+++ b/roms/edk2/ArmPkg/Library/ArmSmcLib/AArch64/ArmSmc.S
@@ -0,0 +1,32 @@
+//
+//  Copyright (c) 2012-2014, ARM Limited. All rights reserved.
+//
+//  SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+//
+
+#include <AsmMacroIoLibV8.h>
+
+ASM_FUNC(ArmCallSmc)
+  // Push x0 on the stack - The stack must always be quad-word aligned
+  str   x0, [sp, #-16]!
+
+  // Load the SMC arguments values into the appropriate registers
+  ldp   x6, x7, [x0, #48]
+  ldp   x4, x5, [x0, #32]
+  ldp   x2, x3, [x0, #16]
+  ldp   x0, x1, [x0, #0]
+
+  smc   #0
+
+  // Pop the ARM_SMC_ARGS structure address from the stack into x9
+  ldr   x9, [sp], #16
+
+  // Store the SMC returned values into the ARM_SMC_ARGS structure.
+  // A SMC call can return up to 4 values - we do not need to store back x4-x7.
+  stp   x2, x3, [x9, #16]
+  stp   x0, x1, [x9, #0]
+
+  mov   x0, x9
+
+  ret