commit a780d10b4f366796966663cf28ac4dff8e0e09e9
author Roman Mazurak <roman.mazurak@infineon.com> Mon Feb 05 21:38:34 2024 +0200
committer Anton Komlev <Anton.Komlev@arm.com> Fri Apr 12 11:30:43 2024 +0200
tree d9f54f4855dfa93b7ad364e8d1443c3ec40dfbcd
parent e6f5d8c065115a2531128066a735cce1345f6197

Exception: Fix PSPSEL for ARMv8-M exception

EXC_RETURN.PSPSEL should be used only if EXC_RETURN.S is equal to
EXC_RETURN.ES (captured by ExceptionTaken). Otherwise CONTROL of
interrupted state should be used to evaluate SPSEL.

This patch use CONTROL_NS.SPSEL to evaluate PSP to capture exception
info generated by non-secure code.

Signed-off-by: Roman Mazurak <roman.mazurak@infineon.com>
Change-Id: I3b71557e44539d92f19541ffb8342c763a847892

platform/ext/common/exception_info.c

diff --git a/platform/ext/common/exception_info.c b/platform/ext/common/exception_info.c
index c9cdc3b..03264ba 100644
--- a/platform/ext/common/exception_info.c
+++ b/platform/ext/common/exception_info.c
@@ -45,8 +45,14 @@
     return ((lr == EXC_RETURN_THREAD_PSP) || (lr == EXC_RETURN_THREAD_PSP_FPU));
 #elif defined(__ARM_ARCH_8M_BASE__) || defined(__ARM_ARCH_8M_MAIN__) \
         || defined(__ARM_ARCH_8_1M_MAIN__)
-    /* PSP is used only if SPSEL is set, and we came from thread mode. */
-    return ((lr & EXC_RETURN_SPSEL) && is_return_thread_mode(lr));
+    if (is_return_secure_stack(lr)) {
+        /* PSP is used only if SPSEL is set, and we came from thread mode. */
+        return ((lr & EXC_RETURN_SPSEL) && is_return_thread_mode(lr));
+    } else {
+        /* PSP is used only if CONTROL_NS.SPSEL is set, and we came from thread mode. */
+        bool sp_sel = _FLD2VAL(CONTROL_SPSEL, __TZ_get_CONTROL_NS()) != 0;
+        return (sp_sel && is_return_thread_mode(lr));
+    }
 #else
     return (lr == EXC_RETURN_THREAD_PSP);
 #endif