[coreboot] Spi flash

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Fri Nov 14 00:05:11 CET 2008

Hi Yves,

On 13.11.2008 20:14, Dupont Yves wrote:
> Thanks for your help, could you tell me what is REMS?

Sure. There are three methods to get an ID from a SPI flash chip:
- RDID: The standard JEDEC Read ID command, usually 3 bytes.
- REMS: Read Electronic Manufacturer Signature, 2 bytes.
- RES: Read Electronic Signature, 1 byte.

RDID and REMS tell you about the vendor, so it is rather easy to find
out the real chip type. RES only gives you a one-byte identifier for the
chip, but there is no way to find out the manufacturer.



More information about the coreboot mailing list