1 files changed, 28 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/mc146818rtc.h b/arch/alpha/include/asm/mc146818rtc.h
new file mode 100644
index 000000000..2154fd4f7
--- /dev/null
+++ b/arch/alpha/include/asm/mc146818rtc.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Machine dependent access functions for RTC registers.
+ */
+#ifndef __ASM_ALPHA_MC146818RTC_H
+#define __ASM_ALPHA_MC146818RTC_H
+
+#include <asm/io.h>
+
+#ifndef RTC_PORT
+#define RTC_PORT(x)	(0x70 + (x))
+#define RTC_ALWAYS_BCD	1	/* RTC operates in binary mode */
+#endif
+
+/*
+ * The yet supported machines all access the RTC index register via
+ * an ISA port access but the way to access the date register differs ...
+ */
+#define CMOS_READ(addr) ({ \
+outb_p((addr),RTC_PORT(0)); \
+inb_p(RTC_PORT(1)); \
+})
+#define CMOS_WRITE(val, addr) ({ \
+outb_p((addr),RTC_PORT(0)); \
+outb_p((val),RTC_PORT(1)); \
+})
+
+#endif /* __ASM_ALPHA_MC146818RTC_H */