[RFC 03/10] eeprom: starfive: Simplify get_ddr_size_from_eeprom()

[Hal Feng <hal.feng@starfivetech.com>]

Directly return the DDR size instead of the field of 'DxxxExxx'.
Move the function description to the header file.

Fixes: aea1bd95b61e ("eeprom: starfive: Enable ID EEPROM configuration")
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
---
 arch/riscv/cpu/jh7110/spl.c                     |  2 +-
 arch/riscv/include/asm/arch-jh7110/eeprom.h     |  8 +++++++-
 .../visionfive2/visionfive2-i2c-eeprom.c        | 17 +++--------------
 3 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/arch/riscv/cpu/jh7110/spl.c b/arch/riscv/cpu/jh7110/spl.c
index 87aaf865246..3aece7d995b 100644
--- a/arch/riscv/cpu/jh7110/spl.c
+++ b/arch/riscv/cpu/jh7110/spl.c
@@ -41,7 +41,7 @@ int spl_dram_init(void)
 	/* Read the definition of the DDR size from eeprom, and if not,
 	 * use the definition in DT
 	 */
-	size = (get_ddr_size_from_eeprom() >> 16) & 0xFF;
+	size = get_ddr_size_from_eeprom();
 	if (check_ddr_size(size))
 		gd->ram_size = size << 30;
 
diff --git a/arch/riscv/include/asm/arch-jh7110/eeprom.h b/arch/riscv/include/asm/arch-jh7110/eeprom.h
index 45ad2a5f7bc..6d0a0ba0c4a 100644
--- a/arch/riscv/include/asm/arch-jh7110/eeprom.h
+++ b/arch/riscv/include/asm/arch-jh7110/eeprom.h
@@ -10,7 +10,13 @@
 #include <linux/types.h>
 
 u8 get_pcb_revision_from_eeprom(void);
-u32 get_ddr_size_from_eeprom(void);
+
+/**
+ * get_ddr_size_from_eeprom() - read DDR size from EEPROM
+ *
+ * @return: size in GiB or 0xFF on error.
+ */
+u8 get_ddr_size_from_eeprom(void);
 
 /**
  * get_mmc_size_from_eeprom() - read eMMC size from EEPROM
diff --git a/board/starfive/visionfive2/visionfive2-i2c-eeprom.c b/board/starfive/visionfive2/visionfive2-i2c-eeprom.c
index 17a44020bcf..3866d07f9d4 100644
--- a/board/starfive/visionfive2/visionfive2-i2c-eeprom.c
+++ b/board/starfive/visionfive2/visionfive2-i2c-eeprom.c
@@ -550,23 +550,12 @@ u8 get_pcb_revision_from_eeprom(void)
 	return pbuf.eeprom.atom1.data.pstr[6];
 }
 
-/**
- * get_ddr_size_from_eeprom - get the DDR size
- * pstr:  VF7110A1-2228-D008E000-00000001
- * VF7110A1/VF7110B1 : VisionFive JH7110A /VisionFive JH7110B
- * D008: 8GB LPDDR4
- * E000: No emmc device, ECxx: include emmc device, xx: Capacity size[GB]
- * return: the field of 'D008E000'
- */
-
-u32 get_ddr_size_from_eeprom(void)
+u8 get_ddr_size_from_eeprom(void)
 {
-	u32 pv = 0xFFFFFFFF;
-
 	if (read_eeprom())
-		return pv;
+		return 0xFF;
 
-	return hextoul(&pbuf.eeprom.atom1.data.pstr[14], NULL);
+	return (hextoul(&pbuf.eeprom.atom1.data.pstr[14], NULL) >> 16) & 0xFF;
 }
 
 u32 get_mmc_size_from_eeprom(void)
-- 
2.43.2