Re: [coreboot] SPD binaries in coreboot

[ron minnich]

Aaron is my hero :-)

ron

On Fri, Oct 23, 2015 at 11:35 AM Aaron Durbin  wrote:
> This one's for Ron.
>
> On Fri, Oct 23, 2015 at 10:32 AM, ron minnich  wrote:
> > Build the tool in go. It's trivial. If you have an idea how it ought to
>
> work
> > I can set it up in the playground in a few minutes.
> >
> > ron
> >
> > On Fri, Oct 23, 2015 at 8:24 AM Patrick Georgi
>
> wrote:
> > > Hi,
> > >
> > > Some mainboards come with soldered-on memory without SPD ROM. For
> > > these, we carry the SPD data in coreboot.
> > >
> > > Currently, they're stored in a hexdump format that is then converted
> > > to binary at build time. The various mechanisms of doing so fail on
> > > some platform or another:
> > > "echo -e -n $stuff" isn't well-liked by some shells (emits "e -n
> > >
> > > $stuff")
> > > "printf '\x42'" isn't well-liked by some shells (or /usr/bin/printf
> > >
> > > tools) that don't support hexadecimal formats
> > > "printf '\0377'" isn't well-liked by some non-conforming, but
>
> existing
> > > shells
> > > xxd -rg1 $file > $file.bin requires xxd, which comes with vim and
> > >
> > > may just not exist
> > >
> > > I see essentially two ways out of this, before we can start reducing
> > > duplication across the tree in that area:
> > > We could build our own tool to parse hex files and dump binary, or we
> > > could ship SPD data as binary from the start (and only have to
> > > concatenate them).
> > >
> > > The second option has the appeal of being much simpler (and there
> > > isn't really a "preferred form" for editing SPD data that I'm aware of
> > > is there?), but looks icky at a glance because it's binary (but it's
> > >
> > > really just as impenetrable as the equivalent hexdump).
> > >
> > > So what do these files contain? Parameters (as in: facts) about the
> > > hardware's size, layout, and timing, and a bunch of vendor/model
> > > identifier strings.
> > >
> > > So, is there a third option that I'm missing? Other opinions?
> > > Patrick
> > > --
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