feat(ras): add RAS system registers access test

FEAT_RAS introduces EL1 system registers to query error records, those
CPU specific parts of the RAS extension can be accessed independently of
any FFH/KFH handling setup or any system specific RAS implementation.

Add a test to verify that those registers can be read, when the CPUID
field advertises the MPAM (CPU) extension.

Change-Id: I7429fc815e7e0ee0cd736603966969b2cfb5f469
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/include/common/test_helpers.h b/include/common/test_helpers.h
index 8ca4cdf..1ab35ba 100644
--- a/include/common/test_helpers.h
+++ b/include/common/test_helpers.h
@@ -279,6 +279,14 @@
 		}                                                               \
 	} while (false)
 
+#define SKIP_TEST_IF_RAS_NOT_SUPPORTED()                                     \
+	do {                                                                 \
+		if(!is_feat_ras_present()){                                  \
+			tftf_testcase_printf("ARMv8.2-RAS not supported\n"); \
+			return TEST_RESULT_SKIPPED;                          \
+		}                                                            \
+	} while (false)
+
 #ifdef __aarch64__
 #define SKIP_TEST_IF_PA_SIZE_LESS_THAN(n)					\
 	do {									\
diff --git a/tftf/tests/extensions/ras/test_ras.c b/tftf/tests/extensions/ras/test_ras.c
new file mode 100644
index 0000000..cd27f16
--- /dev/null
+++ b/tftf/tests/extensions/ras/test_ras.c
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2025, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <test_helpers.h>
+#include <tftf_lib.h>
+#include <tftf.h>
+
+/*
+ * FEAT_RAS introduces EL1 system registers to query error records, those
+ * CPU specific parts of the RAS extension can be accessed independently of
+ * any FFH/KFH handling setup or any system specific RAS implementation.
+ * Reading these registers will trap to EL3 and crash when EL3 has not
+ * allowed access, which is controlled by the SCR_EL3.TERR bit.
+ */
+
+test_result_t test_ras_reg_access(void)
+{
+	SKIP_TEST_IF_AARCH32();
+
+#ifdef __aarch64__
+	SKIP_TEST_IF_RAS_NOT_SUPPORTED();
+
+	read_erridr_el1();
+
+	return TEST_RESULT_SUCCESS;
+#endif
+}
diff --git a/tftf/tests/tests-cpu-extensions.mk b/tftf/tests/tests-cpu-extensions.mk
index 9358c49..37e41de 100644
--- a/tftf/tests/tests-cpu-extensions.mk
+++ b/tftf/tests/tests-cpu-extensions.mk
@@ -19,6 +19,7 @@
 	extensions/mte/test_mte.c					\
 	extensions/pauth/test_pauth.c					\
 	extensions/pmuv3/test_pmuv3.c					\
+	extensions/ras/test_ras.c					\
 	extensions/sctlr2/test_sctlr2.c					\
 	extensions/sme/test_sme.c					\
 	extensions/sme/test_sme2.c					\
diff --git a/tftf/tests/tests-cpu-extensions.xml b/tftf/tests/tests-cpu-extensions.xml
index 632e231..dd60bc1 100644
--- a/tftf/tests/tests-cpu-extensions.xml
+++ b/tftf/tests/tests-cpu-extensions.xml
@@ -19,6 +19,7 @@
     <testcase name="Check for Pointer Authentication key leakage from EL3" function="test_pauth_leakage" />
     <testcase name="Check for Pointer Authentication key leakage from TSP" function="test_pauth_leakage_tsp" />
     <testcase name="Access MPAM registers" function="test_mpam_reg_access" />
+    <testcase name="Access RAS registers" function="test_ras_reg_access" />
     <testcase name="Use MTE Instructions" function="test_mte_instructions" />
     <testcase name="Check for MTE register leakage" function="test_mte_leakage" />
     <testcase name="Use FGT Registers" function="test_fgt_enabled" />