Page MenuHomeFreeBSD

Ensure the boot CPU is CPU 0 on arm64
ClosedPublic

Authored by andrew on Dec 7 2020, 1:05 PM.
Tags
None
Referenced Files
Unknown Object (File)
Tue, Jul 21, 4:14 AM
Unknown Object (File)
Tue, Jul 21, 12:35 AM
Unknown Object (File)
Sat, Jul 11, 3:59 AM
Unknown Object (File)
Sat, Jul 4, 12:53 PM
Unknown Object (File)
Fri, Jul 3, 5:55 AM
Unknown Object (File)
Jun 20 2026, 5:51 PM
Unknown Object (File)
Jun 4 2026, 12:22 AM
Unknown Object (File)
May 14 2026, 4:32 AM
Subscribers

Details

Summary

We assume the boot CPU is always CPU 0 on arm64. To allow for this reserve
cpuid 0 for the boot CPU in the ACPI and FDT cases but otherwise start the
CPU as normal. We then check for the boot CPU in start_cpu and return as if
it was started.

While here extract the FDT CPU init code into a new function to simplify
cpu_mp_start and return FALSE from start_cpu when the CPU fails to start.

Diff Detail

Repository
rS FreeBSD src repository - subversion
Lint
Lint Not Applicable
Unit
Tests Not Applicable

Event Timeline

andrew requested review of this revision.Dec 7 2020, 1:05 PM

Simplify by only iterating once with CPU 0 being reserved

  • Use the correct ID in cpu_init_fdt
  • Copy a comment explaining why we don't increment the CPU ID to teh FDT code
  • Fix a typo in said comment
mmel added a subscriber: mmel.

Works for me and it's much better than my initial proposal.

This revision is now accepted and ready to land.Dec 7 2020, 4:37 PM
This revision was automatically updated to reflect the committed changes.