In message 513a5e60605211549v34ee26bfq313e93195c2479e3@mail.gmail.com you wrote:
The u-boot/include/configs/ebony.h file has the following #defines (line 13= 6):
#define CONFIG_SPD_EEPROM /* Use SPD EEPROM for setup */ #define SPD_EEPROM_ADDRESS {0x53,0x52} /* SPD i2c spd addresses */
The PPC440GP evaluation board user's manual says on Page 63 (also on Page 46) that the SPD EEPROM addresses are 0xA6, 0xA7 (for DIMM0) and 0xA4, 0xA5 (for DIMM1).
Why is there a difference between these addresses? Am I even looking at the right addresses or am I totally missing something?
There is actually no difference. I2C addresses are 7 bit and occupy the 7 high order bits in a byte. The LSB is used to indiccat read or write accesses.
So you get: DIMM0: 0xA6 >> 1 = 0x53 0xA7 >> 1 = 0x53
and: DIMM1: 0xA4 >> 1 = 0x52 0xA5 >> 1 = 0x52
You see?
Best regards,
Wolfgang Denk