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authorIru Cai <mytbk920423@gmail.com>2019-10-30 14:21:52 +0800
committerIru Cai <mytbk920423@gmail.com>2019-10-30 14:48:38 +0800
commitae51f41d14f548d494ac41e0d21137c5a4c3f59c (patch)
tree6ddb9d1aaa7bd5bad5bbf8497edc2e08ff208d79 /arch/x86/include/asm/early_cmos.h
downloaduext4-ae51f41d14f548d494ac41e0d21137c5a4c3f59c.tar.xz
import the U-Boot code and make it compile
Diffstat (limited to 'arch/x86/include/asm/early_cmos.h')
-rw-r--r--arch/x86/include/asm/early_cmos.h42
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/x86/include/asm/early_cmos.h b/arch/x86/include/asm/early_cmos.h
new file mode 100644
index 0000000..543a9e6
--- /dev/null
+++ b/arch/x86/include/asm/early_cmos.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#ifndef __EARLY_CMOS_H
+#define __EARLY_CMOS_H
+
+/* CMOS actually resides in the RTC SRAM */
+#define CMOS_IO_PORT 0x70
+
+/**
+ * cmos_read8() - Get 8-bit data stored at the given address
+ *
+ * This reads from CMOS for the 8-bit data stored at the given address.
+ *
+ * @addr: RTC SRAM address
+ * @return: 8-bit data stored at the given address
+ */
+u8 cmos_read8(u8 addr);
+
+/**
+ * cmos_read16() - Get 16-bit data stored at the given address
+ *
+ * This reads from CMOS for the 16-bit data stored at the given address.
+ *
+ * @addr: RTC SRAM address
+ * @return: 16-bit data stored at the given address
+ */
+u16 cmos_read16(u8 addr);
+
+/**
+ * cmos_read32() - Get 32-bit data stored at the given address
+ *
+ * This reads from CMOS for the 32-bit data stored at the given address.
+ *
+ * @addr: RTC SRAM address
+ * @return: 32-bit data stored at the given address
+ */
+u32 cmos_read32(u8 addr);
+
+#endif /* __EARLY_CMOS_H */