test(el3-runtime): dit is retained on world switch
Add tsp service to check the value of the PSTATE DIT bit is as
expected and toggle it's value. This is used to ensure that
the DIT bit is maintained during a switch from the Normal to
Secure worlds and back.
Change-Id: I4e8bdfa6530e5e75925c0079d4fa2795133c5105
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
diff --git a/bl32/tsp/tsp_main.c b/bl32/tsp/tsp_main.c
index 55e1532..522c1b4 100644
--- a/bl32/tsp/tsp_main.c
+++ b/bl32/tsp/tsp_main.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2022, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -370,6 +370,7 @@
uint64_t service_arg1;
uint64_t results[2];
uint32_t linear_id = plat_my_core_pos();
+ u_register_t dit;
/* Update this cpu's statistics */
tsp_stats[linear_id].smc_count++;
@@ -424,6 +425,23 @@
results[0] /= service_arg0 ? service_arg0 : 1;
results[1] /= service_arg1 ? service_arg1 : 1;
break;
+ case TSP_CHECK_DIT:
+ if (!is_armv8_4_dit_present()) {
+#if LOG_LEVEL >= LOG_LEVEL_ERROR
+ spin_lock(&console_lock);
+ ERROR("DIT not supported\n");
+ spin_unlock(&console_lock);
+#endif
+ results[0] = 0;
+ results[1] = 0xffff;
+ break;
+ }
+ dit = read_dit();
+ results[0] = dit == service_arg0;
+ results[1] = dit;
+ /* Toggle the dit bit */
+ write_dit(service_arg0 != 0U ? 0 : DIT_BIT);
+ break;
default:
break;
}