ArmPkg/OpteeLib: Add dummy RPC handler

Add dummy RPC handler for RPCs that are not implemented as control
should be returned back to OP-TEE in case any RPC is invoked.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

diff --git a/ArmPkg/Library/OpteeLib/Optee.c b/ArmPkg/Library/OpteeLib/Optee.c
index 55dcc7853b596de2fb8dce2c9da02cc818f3191d..ed2a03c593c27213b838ac6faa8de04587dc7305 100644 (file)
--- a/ArmPkg/Library/OpteeLib/Optee.c
+++ b/ArmPkg/Library/OpteeLib/Optee.c
@@ -123,6 +123,17 @@ OpteeInit (
   return EFI_SUCCESS;\r
 }\r
 \r
+STATIC\r
+BOOLEAN\r
+IsOpteeSmcReturnRpc (\r
+  UINT32 Return\r
+  )\r
+{\r
+  return (Return != OPTEE_SMC_RETURN_UNKNOWN_FUNCTION) &&\r
+         ((Return & OPTEE_SMC_RETURN_RPC_PREFIX_MASK) ==\r
+          OPTEE_SMC_RETURN_RPC_PREFIX);\r
+}\r
+\r
 /**\r
   Does Standard SMC to OP-TEE in secure world.\r
 \r
@@ -147,13 +158,22 @@ OpteeCallWithArg (
   while (TRUE) {\r
     ArmCallSmc (&ArmSmcArgs);\r
 \r
-    if (ArmSmcArgs.Arg0 == OPTEE_SMC_RETURN_RPC_FOREIGN_INTERRUPT) {\r
-      //\r
-      // A foreign interrupt was raised while secure world was\r
-      // executing, since they are handled in UEFI a dummy RPC is\r
-      // performed to let UEFI take the interrupt through the normal\r
-      // vector.\r
-      //\r
+    if (IsOpteeSmcReturnRpc (ArmSmcArgs.Arg0)) {\r
+      switch (ArmSmcArgs.Arg0) {\r
+      case OPTEE_SMC_RETURN_RPC_FOREIGN_INTERRUPT:\r
+        //\r
+        // A foreign interrupt was raised while secure world was\r
+        // executing, since they are handled in UEFI a dummy RPC is\r
+        // performed to let UEFI take the interrupt through the normal\r
+        // vector.\r
+        //\r
+        break;\r
+\r
+      default:\r
+         // Do nothing in case RPC is not implemented.\r
+        break;\r
+      }\r
+\r
       ArmSmcArgs.Arg0 = OPTEE_SMC_RETURN_FROM_RPC;\r
     } else {\r
       break;\r

diff --git a/ArmPkg/Library/OpteeLib/OpteeSmc.h b/ArmPkg/Library/OpteeLib/OpteeSmc.h
index 9cccd81810c9d03343db223120e1d6f571f71da3..6209782aaed710625c345887f6e27a0c71a1446c 100644 (file)
--- a/ArmPkg/Library/OpteeLib/OpteeSmc.h
+++ b/ArmPkg/Library/OpteeLib/OpteeSmc.h
@@ -25,6 +25,9 @@
 \r
 #define OPTEE_SMC_SHARED_MEMORY_CACHED          1\r
 \r
+#define OPTEE_SMC_RETURN_UNKNOWN_FUNCTION       0xffffffff\r
+#define OPTEE_SMC_RETURN_RPC_PREFIX_MASK        0xffff0000\r
+#define OPTEE_SMC_RETURN_RPC_PREFIX             0xffff0000\r
 #define OPTEE_SMC_RETURN_RPC_FOREIGN_INTERRUPT  0xffff0004\r
 \r
 #define OPTEE_MESSAGE_COMMAND_OPEN_SESSION      0\r