arm: Return the current handler from arm_cp15_set_exception_handler

Closes #3762

2 files changed, 13 insertions, 3 deletions

diff --git a/bsps/arm/shared/cp15/arm-cp15-set-exception-handler.c b/bsps/arm/shared/cp15/arm-cp15-set-exception-handler.c
index b24b7c4eb0..a0cec87589 100644
--- a/bsps/arm/shared/cp15/arm-cp15-set-exception-handler.c
+++ b/bsps/arm/shared/cp15/arm-cp15-set-exception-handler.c
@@ -16,15 +16,18 @@
 
 #include <bsp/linker-symbols.h>
 
-void arm_cp15_set_exception_handler(
+void* arm_cp15_set_exception_handler(
   Arm_symbolic_exception_name exception,
   void (*handler)(void)
 )
 {
+  uint32_t current_handler = 0;
+
   if ((unsigned) exception < MAX_EXCEPTIONS) {
     uint32_t *cpu_table = (uint32_t *) 0 + MAX_EXCEPTIONS;
     uint32_t *mirror_table = (uint32_t *) bsp_vector_table_begin + MAX_EXCEPTIONS;
-    uint32_t current_handler = mirror_table[exception];
+
+    current_handler = mirror_table[exception];
 
     if (current_handler != (uint32_t) handler) {
       size_t table_size = MAX_EXCEPTIONS * sizeof(uint32_t);
@@ -53,4 +56,6 @@ void arm_cp15_set_exception_handler(
       rtems_interrupt_local_enable(level);
     }
   }
+
+  return (void*) current_handler;
 }
diff --git a/cpukit/score/cpu/arm/include/libcpu/arm-cp15.h b/cpukit/score/cpu/arm/include/libcpu/arm-cp15.h
index 506d61a082..6e66b15b07 100644
--- a/cpukit/score/cpu/arm/include/libcpu/arm-cp15.h
+++ b/cpukit/score/cpu/arm/include/libcpu/arm-cp15.h
@@ -2246,7 +2246,12 @@ uint32_t arm_cp15_set_translation_table_entries(
   uint32_t section_flags
 );
 
-void arm_cp15_set_exception_handler(
+/**
+ * @brief Sets the @a exception @a handler in the vector table.
+ *
+ * @return Previous handler.
+ */
+void* arm_cp15_set_exception_handler(
   Arm_symbolic_exception_name exception,
   void (*handler)(void)
 );