riscv: rework CPU identification [2/6]
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Authored by mhorne on Apr 25 2023, 5:24 PM.

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Reviewers

markj

Group Reviewers

riscv

Commits

rGbcb838d17a9b: riscv: Call identify_cpu() earlier for CPU 0
rGb0d45b023e8c: riscv: Call identify_cpu() earlier for CPU 0

Summary

Call identify_cpu() earlier for the BSP.

It is advantageous to have knowledge of ISA features as early as
possible. For example, the presence of newer virtual memory extensions
may be useful to pmap_bootstrap().

To achieve this, split out the printf() parts of identify_cpu() into a
separate function, identify_cpu_report(). This latter function will be
called later in boot after the console has been initialized.

Plus, a small trick in init_secondary() allows us to avoid interlaced
output from concurrent calls to identify_cpu_report() as APs are
started.

Diff Detail

Repository

rG FreeBSD src repository

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Lint Passed

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No Test Coverage

Build Status

Buildable 51401
Build 48292: arc lint + arc unit

Event Timeline

mhorne created this revision.Apr 25 2023, 5:24 PM

Herald added a subscriber: imp. · View Herald TranscriptApr 25 2023, 5:24 PM

mhorne requested review of this revision.Apr 25 2023, 5:24 PM

Harbormaster completed remote builds in B51184: Diff 121017.Apr 25 2023, 5:24 PM

mhorne added a parent revision: D39809: riscv: rework CPU identification [1/6].Apr 25 2023, 5:24 PM

mhorne added a child revision: D39811: riscv: rework CPU identification [3/6].

markj accepted this revision.Apr 26 2023, 2:23 PM

This revision is now accepted and ready to land.Apr 26 2023, 2:23 PM

jhb added a subscriber: jhb.May 1 2023, 6:41 PM

jhb added inline comments.

sys/riscv/riscv/mp_machdep.c
290	On x86 this is called printcpuinfo(). arm64 appears to do this as a SYSINIT later in boot instead (cpu_features_sysinit). I think I'd prefer to try to aim for some sort of consistency for function names maybe? x86 is a bit more of a mess as it splits identify_cpu up into multiple routines for multiple steps, but might be nice to call this printcpuinfo at least. arm64 prints the info for the APs on the BSP FWIW in the sysinit rather than doing it during AP startup. For x86 we assume all cores are the same and don't bother printing any features for APs.