diff --git a/os/rt/ports/ARMCMx/chcore_v7m.h b/os/rt/ports/ARMCMx/chcore_v7m.h
index ed78d1bce..2d5b82a9e 100644
--- a/os/rt/ports/ARMCMx/chcore_v7m.h
+++ b/os/rt/ports/ARMCMx/chcore_v7m.h
@@ -457,13 +457,13 @@ static inline void port_lock(void) {
 
 #if CORTEX_SIMPLIFIED_PRIORITY == FALSE
 #if defined(__CM7_REV)
-#if __CM7_REV == 0
+#if __CM7_REV <= 1
   __disable_irq();
 #endif
 #endif
   __set_BASEPRI(CORTEX_BASEPRI_KERNEL);
 #if defined(__CM7_REV)
-#if __CM7_REV == 0
+#if __CM7_REV <= 1
   __enable_irq();
 #endif
 #endif