Merge pull request #5597 from 0xc0170/fix_#5555

critical: fix set exclusive access if not yet defined

Author: cmonr

platform/mbed_critical.c

@@ -24,6 +24,25 @@
 #include "platform/mbed_critical.h"
 #include "platform/mbed_toolchain.h"
 
+// if __EXCLUSIVE_ACCESS rtx macro not defined, we need to get this via own-set architecture macros
+#ifndef MBED_EXCLUSIVE_ACCESS
+#ifndef __EXCLUSIVE_ACCESS
+#if ((__ARM_ARCH_7M__      == 1U) || \
+    (__ARM_ARCH_7EM__     == 1U) || \
+    (__ARM_ARCH_8M_BASE__ == 1U) || \
+    (__ARM_ARCH_8M_MAIN__ == 1U)) || \
+    (__ARM_ARCH_7A__ == 1U)
+#define MBED_EXCLUSIVE_ACCESS      1U
+#elif (__ARM_ARCH_6M__ == 1U)
+#define MBED_EXCLUSIVE_ACCESS      0U
+#else
+#error "Unknown architecture for exclusive access"
+#endif
+#else 
+#define MBED_EXCLUSIVE_ACCESS __EXCLUSIVE_ACCESS
+#endif
+#endif
+
 static volatile uint32_t critical_section_reentrancy_counter = 0;
 
 bool core_util_are_interrupts_enabled(void)
@@ -90,7 +109,7 @@ void core_util_critical_section_exit(void)
     }
 }
 
-#if __EXCLUSIVE_ACCESS
+#if MBED_EXCLUSIVE_ACCESS
 
 /* Supress __ldrex and __strex deprecated warnings - "#3731-D: intrinsic is deprecated" */
 #if defined (__CC_ARM)