--- zzzz-none-000/linux-3.10.107/arch/sparc/include/asm/mc146818rtc.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/sparc/include/asm/mc146818rtc.h	2021-02-04 17:41:59.000000000 +0000
@@ -1,5 +1,10 @@
 #ifndef ___ASM_SPARC_MC146818RTC_H
 #define ___ASM_SPARC_MC146818RTC_H
+
+#include <linux/spinlock.h>
+
+extern spinlock_t rtc_lock;
+
 #if defined(__sparc__) && defined(__arch64__)
 #include <asm/mc146818rtc_64.h>
 #else