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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Patrick Georgi