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You'll want to have some folks look a bit closer at some of the specifics. I just have a few comments that mostly stem from my own confusion I think.
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This is a fix for #596, #595, and #568.
In oxidecomputer/hubris#2094, we moved the SPD data to a parameterized
struct SpdData<const DIMM_COUNT: usize, const DATA_SIZE: usize>. This is because Cosmo has a different number of DIMMS (16 → 12), and their SPD data are a different size (512 → 1024 bytes).Unfortunately, this broke Humility, which was expecting an array named
spd_dataand instead found astruct.Cosmo is also broken because DDR5 has a different SPD layout than DDR4; even if we could read the
struct, we wouldn't know how to parse it.This PR fixes both things, flexibly decoding the
SpdDataand printing both DDR4 and DDR5 SPDs. (This required updating thespdcrate with DDR5 info)To avoid a giant diff, this doesn't add new dumps for the test suite, but I'm planning to add them in a subsequent PR.
Here's an example of Cosmo output: