Non-Secure Interrupt support during Standard SMC processing in TSP

Implements support for Non Secure Interrupts preempting the
Standard SMC call in EL1. Whenever an IRQ is trapped in the
Secure world we securely handover to the Normal world
to process the interrupt. The normal world then issues
"resume" smc call to resume the previous interrupted SMC call.
Fixes ARM-software/tf-issues#105

Change-Id: I72b760617dee27438754cdfc9fe9bcf4cc024858
diff --git a/bl32/tsp/aarch64/tsp_entrypoint.S b/bl32/tsp/aarch64/tsp_entrypoint.S
index 54276f2..9999c43 100644
--- a/bl32/tsp/aarch64/tsp_entrypoint.S
+++ b/bl32/tsp/aarch64/tsp_entrypoint.S
@@ -39,8 +39,11 @@
 	.globl	tsp_cpu_suspend_entry
 	.globl	tsp_cpu_resume_entry
 	.globl	tsp_fast_smc_entry
+	.globl	tsp_std_smc_entry
 	.globl	tsp_fiq_entry
 
+
+
 	/* ---------------------------------------------
 	 * Populate the params in x0-x7 from the pointer
 	 * to the smc args structure in x0.
@@ -317,8 +320,22 @@
 	 * ---------------------------------------------
 	 */
 func tsp_fast_smc_entry
-	bl	tsp_fast_smc_handler
+	bl	tsp_smc_handler
 	restore_args_call_smc
 tsp_fast_smc_entry_panic:
 	b	tsp_fast_smc_entry_panic
 
+	/*---------------------------------------------
+	 * This entrypoint is used by the TSPD to ask
+	 * the TSP to service a std smc request.
+	 * We will enable preemption during execution
+	 * of tsp_smc_handler.
+	 * ---------------------------------------------
+	 */
+func tsp_std_smc_entry
+	msr	daifclr, #DAIF_FIQ_BIT | DAIF_IRQ_BIT
+	bl	tsp_smc_handler
+	msr	daifset, #DAIF_FIQ_BIT | DAIF_IRQ_BIT
+	restore_args_call_smc
+tsp_std_smc_entry_panic:
+	b	tsp_std_smc_entry_panic