Attention is currently required from: Paul Menzel, Tim Wawrzynczak. Reka Norman has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58929 )
Change subject: spd: Add new LP5 parts and generate SPDs ......................................................................
Patch Set 3:
(3 comments)
Commit Message:
https://review.coreboot.org/c/coreboot/+/58929/comment/f3178d6c_14ff15b1 PS2, Line 12: MT62F512M32D2DR-031 WT:B : MT62F1G32D4DR-031 WT:B : H9JCNNNCP3MLYR-N6E
Please add the vendors.
Done
File spd/lp5/memory_parts.json:
https://review.coreboot.org/c/coreboot/+/58929/comment/a4fe8e4a_8769dd13 PS2, Line 19: 2,
Perhaps I'm misunderstanding the datasheet, but isn't this also 1 like the 512M32?
I was basing this off Table 2 in the datasheet, which shows 2 ranks per channel.
Also, the block diagram in Figure 3 shows 2 CSs for each channel: CS0_A/B and CS1_A/B.
https://review.coreboot.org/c/coreboot/+/58929/comment/8638de8d_743b3398 PS2, Line 27: 4,
I only see one ZQ ball per package on this part.
I know for LP4x there was one ZQ ball per die, so this was used as an indicator of the number of dies. But I think it's different for LP5 because multiple dies can share a ZQ ball.
From 16.6 ZQ Wiring in JESD209-5B:
LPDDR5 devices are designed to allow up to NZQ die within a single package to connect to a common ZQ resource. When multiple die share a ZQ resource, one die is designated as the Initiator die.
The block diagram on this part's datasheet also shows 4 dies sharing a single ZQ pin.
I might be missing something, but based on the LP5 tables in advisory #616599, I think for LP5 the dies per package is literally just the number of physical dies. I.e. since the datasheet says QDP and show 4 dies in the block diagram, diesPerPackage should be 4.
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Reka Norman (Code Review)