[coreboot-gerrit] Change in coreboot[master]: automation: add empty_ddr4.spd.hex to Makefile.inc

[Paul Fagerburg (Code Review)]

Paul Fagerburg has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/36068 )

Change subject: automation: add empty_ddr4.spd.hex to Makefile.inc
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Patch Set 3:
> Patch Set 3:
>
> Wonder if it would be better to allow an empty SPD_SOURCES and print an info instead of an error in spd/Makefile.inc.

Allowing an empty SPD_SOURCES means we need extra logic for when spd.bin doesn't exist (because it only gets built if SPD_SOURCES is non-empty), and then the C array that points to the SPD data has to have special logic as well. And then when you try to run your code, it doesn't work because you don't have any SPD for your DRAM so MRC doesn't know what to do.

On the other hand, if we start with an "empty" SPD, we have one slot filled, spd.bin gets built, the C array has some contents, it's just that (as before) your code won't work, though this time it's because the SPD doesn't work for the DRAM you have.