diff --git a/cpu/cortexm_common/include/cpu.h b/cpu/cortexm_common/include/cpu.h
index 0b6f294b11e0e2fd8a754bf9b4771cfc42065ef9..416ecda7b4f9665c8b827b9ebe4a0990bcdd8701 100644
--- a/cpu/cortexm_common/include/cpu.h
+++ b/cpu/cortexm_common/include/cpu.h
@@ -62,17 +62,6 @@ extern "C" {
 #endif
 /** @} */
 
-/**
- * @brief   UART0 buffer size definition for compatibility reasons
- *
- * @todo remove once the remodeling of the uart0 driver is done
- * @{
- */
-#ifndef UART0_BUFSIZE
-#define UART0_BUFSIZE                   (128)
-#endif
-/** @} */
-
 /**
  * @brief   Deprecated interrupt control function for backward compatibility
  * @{