Change in coreboot[master]: timestamp: Add new helper functions

[Julius Werner (Code Review)]

Attention is currently required from: Bora Guvendik, Furquan Shaikh, Selma Bensaid, Tim Wawrzynczak, Subrata Banik, Angel Pons, Aaron Durbin.
Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51445 )

Change subject: timestamp: Add new helper functions
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Patch Set 8:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/51445/comment/755688be_b048bb57 
PS3, Line 7: Add helper fucntions
> > > Thanks Angel and Julius for your suggestion. […]

Subrata, the problem is that you're flipping the sign on the negative timestamps in https://review.coreboot.org/c/coreboot/+/59555/2/util/cbmem/cbmem.c#618, and you shouldn't. If you don't then the sorting will happen exactly as Angel said, 944 first, then in order up to 947, then timestamp 0, then the positive ones. That is what we want.

Please see my comment on CB:59555, it should really just take a couple of lines to do this, not a second sort and all the extra stuff you're doing. The final output should be

944:CSE sent 'Boot Stall Done' to PMC                 0
 945:CSE started to handle ICC configuration           766,000 (766,000)
 946:CSE sent 'Host BIOS Prep Done' to PMC             771,000 (5,000)
 947:CSE received 'CPU Reset Done Ack sent' from PMC   778,000 (7,000)
   0:1st timestamp                                     1,074,000 (296,000)

(We could also choose not to set the first timestamp to 0 and print the numbers negative as they are if you prefer that... but I think that would be more confusing than helpful.)