board: sifive: Add an interface to get PCB revision
There are different DDR parameter settings for different board
revisions. Add a new interface to get the PCB revision to determine
which DT should be selected at runtime.
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/arch/riscv/include/asm/arch-fu740/eeprom.h b/arch/riscv/include/asm/arch-fu740/eeprom.h
new file mode 100644
index 0000000..0e1220e
--- /dev/null
+++ b/arch/riscv/include/asm/arch-fu740/eeprom.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2021 SiFive, Inc.
+ *
+ * Zong Li <zong.li@sifve.com>
+ */
+
+#ifndef _ASM_RISCV_EEPROM_H
+#define _ASM_RISCV_EEPROM_H
+
+#define PCB_REVISION_REV3 0x3
+
+u8 get_pcb_revision_from_eeprom(void);
+
+#endif /* _ASM_RISCV_EEPROM_H */