Re: [coreboot] spd binaries

[sebastien basset]

Thanks you for your answers, finally i use decode-dimms for check value
because i have an spb binary with others reference component very close, i
had compare with documentation.

Be careful: Only problems, the input file of decode-dimms take output
hexdump -C exactly ( with numbers line ) else decode-dimms doesn't work.

thank you for your contribution.

2016-12-17 13:51 GMT+01:00 Pok Gu :
> The difficulty with calculating by hand is there are some checksum bits.
> If your goal is to overclock the ram to maximize its performance, you
> probably have to do it again and again for servel times so that the ram
> reaches its best performance without failing the memtest (the higher the
> speed the more likely to fail the memtest). Without a tool or a script the
> checksum bits has to be calculated everytime by hand...I am calling for a
> tool to make this eaiser...
>
> Possibly you don't need to invest extra money (but just some time) to use
> that tool. Thaiphoon Burner has a free version that it does not allow you
> to save the spd.bin but it has a hex editor that can show you the modified
> hex bits and the calculated checksum. It can be used as a reference. Then
> manually modify the spd.bin file and write it using some free tools (e.g.,
> RWEveryting on Windows or eeprom/i2c-tool on Linux).
>
> 2016-12-17 5:21 GMT+08:00 David Hendricks :
> > On Fri, Dec 16, 2016 at 11:01 AM, Pok Gu  wrote:
> > > Thaiphoon Burne is the most popular and probably the only tool for
> > > modifying the spd.bin. It has many built-in templates and you only need to
> > > select the speed, clocking, and voltage you like (e.g., DDR3-1688/DDR3-1333
> > > and CL10/CL11 and 1.35V/1.5V) and it will do all the rest calculations and
> > > generate the spd.bin for you. Then, the only thing you need to do is to
> > > flash the spd.bin to the spd chip on the ram, and reboot, and your ram
> > > stick is overclocked.
> > >
> > > Unfortunately, it is only available on Windows. So I have one harddisk
> > > loaded with Windows 7 and Thaiphoon Burne specialized for this work.
> > >
> > > I haven't found any linux software can do this unless you calculate and
> > > modify the spd.bin by hand. (If anyone found one let me know)
> >
> > Cool - I never knew about that tool. Seems like a good investment if the
> > goal is to generate an spd.bin from scratch.
> >
> > Sebastien - What are you trying to do, exactly? If you only need to
> > change one or two parameters, then a hex editor and a calculator should be
> > sufficient. The relevant specification for SPDs is JEDEC Standard No. 21-C
> > Annex K for DDR3 and Annex L for DDR4. (you'll need to register with
> > jedec.org to download the specs)