[coreboot-gerrit] Change in coreboot[master]: timestamp: Allow timestamp_add to accept a negative number

[Julius Werner (Code Review)]

Attention is currently required from: Bora Guvendik, Selma Bensaid, Subrata Banik.
Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59554 )

Change subject: timestamp: Allow timestamp_add to accept a negative number
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Patch Set 1:

(1 comment)

File src/lib/timestamp.c:

https://review.coreboot.org/c/coreboot/+/59554/comment/2d15b7ec_5745a0f8 
PS1, Line 134: 	if (ts_time >= 0)
No, not like this. It should still subtract base_time so the behavior is consistent for both positive and negative values. As long as you call timestamp_add() with the right value (which should be the time difference in timestamp-frequency between the point where the TSC counter started ticking and when the actual event happened, expressed as a negative number), it should work out to the right thing in the end.